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Molecular Dynamics simulation and docking of the QS-13 peptide. (a) The snapshots extracted from MD simulations of the QS-13-db (left panel) and QS-13 (central panel) peptides were superimposed using the α carbons of the CQVC central sequence. A first type of display (upper panel) is obtained with the licorice representation picturing the CQVC central residues (atom color coded) and the Arginine residue (in light green). The second type of display (lower panel) is obtained using the licorice representation for the CQVC central residues (atom color coded) and the new cartoon representation for the backbone (in silver). Finally, superimposition of the first cluster of the disulfide bonded peptides was performed (right panel). The structures of the AS-13-db (in red), QS-13-R5A-db (in silver) and QS-13-db (in blue) were superimposed using the α carbons of the CQVC central sequence. The backbone is displayed using the new cartoon representation, the CQVC sequence using the licorice representation and the Arginine residues using the Van der Waals representation. (b) Specification of the QS-13 peptides characteritics related to the origin of the cluster (family of conformation) and the nature of the termini. (c) Representative conformation of QS-13 peptides. N-termini are displayed in green licorice and C-termini in red licorice. The backbone of the peptides is colored according to its local secondary structure (cyan for turn and white for coil) and the sulfur atoms are shown as yellow spheres. (d) The results of the QS-13-3 docking experiment highlight the existence of 5 Preferred
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Tetrastatin, a 230 amino acid sequence from collagen IV, was previously demonstrated to inhibit melanoma progression. In the present paper, we identified the minimal active sequence (QKISRCQVCVKYS: QS-13) that reproduced the anti-tumor effects of whole Tetrastatin in vivo and in vitro on melanoma cell prolifération, migration and invasion. We demon...
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... experiments of QS-13 on α V β 3 . For each QS-13 peptide (listed in Fig. 4b), we collected 27000 (180 × 150) structures from the docking experiments. To overcome the bias introduced by the forced explora- tion of empty or unfavourable interaction areas, we kept the first 180 lowest energy structures and studied them in detail. These structures were then spatially regrouped in clusters to allow identification of the most probable interacting surface protein areas. For each QS-13 peptide, we identified the preferred areas of interaction (PAI) with the integrin; at the most, five were identified. In the left panel of Fig. 4d, the five PAIs found with the QS-13-3 peptide (also representative of the results obtained with the other peptides) are shown. Most often for 4 QS-13 peptides out of the 6 investigated through docking, as shown in Fig. 4b, PAI-5 was the area that had the highest frequency (see Table S3). From the energetic point of view, the negative binding energies accounted for the favourable interactions between the QS-13 peptide and this area of α v β 3 . On average, PAI-3 was the least populated area. It was not explored by the QS-13-2 peptide, and in 3 of the 5 experiments, the lowest binding energy did not traduce any favourable interaction since it was close to zero. Other than PAI-3, which could be removed from the potential interacting areas, it seemed difficult to remove the remaining PAI. Looking at the energy, 2 out of the 6 peptides seemed to be very interesting, QS-13-5 and QS-13-6, since they had at least 4 of the lowest binding energies below the threshold of −3.00 kcal/mol. New docking experiments were performed with bonded QS-13, positioning the centres of the grid search on the centre of mass of each PAI. Following this protocol, we were able to identify the residues of the integrin that interacted directly the QS-13 peptides (central and right panel of Fig. 4d). It was interesting to observe that among the residues that made contact with the QS-13 peptide, the aspartic acid residue was one of the most common, followed by glutamic acid, tyrosine and serine. Focusing the contact investigation on the best binding energy structure obtained in the PAI-1 region, we again highlight the fact that the contacts made by QS-13 mostly involved these four types of residues in the protein. Finally, when we compare our docking results with 1L5G PDB structure 20 , we observe that the position of PAI-1 is colocalized with the region of interaction between the RGD peptide and the ...
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... experiments of QS-13 on α V β 3 . For each QS-13 peptide (listed in Fig. 4b), we collected 27000 (180 × 150) structures from the docking experiments. To overcome the bias introduced by the forced explora- tion of empty or unfavourable interaction areas, we kept the first 180 lowest energy structures and studied them in detail. These structures were then spatially regrouped in clusters to allow identification of the most probable interacting surface protein areas. For each QS-13 peptide, we identified the preferred areas of interaction (PAI) with the integrin; at the most, five were identified. In the left panel of Fig. 4d, the five PAIs found with the QS-13-3 peptide (also representative of the results obtained with the other peptides) are shown. Most often for 4 QS-13 peptides out of the 6 investigated through docking, as shown in Fig. 4b, PAI-5 was the area that had the highest frequency (see Table S3). From the energetic point of view, the negative binding energies accounted for the favourable interactions between the QS-13 peptide and this area of α v β 3 . On average, PAI-3 was the least populated area. It was not explored by the QS-13-2 peptide, and in 3 of the 5 experiments, the lowest binding energy did not traduce any favourable interaction since it was close to zero. Other than PAI-3, which could be removed from the potential interacting areas, it seemed difficult to remove the remaining PAI. Looking at the energy, 2 out of the 6 peptides seemed to be very interesting, QS-13-5 and QS-13-6, since they had at least 4 of the lowest binding energies below the threshold of −3.00 kcal/mol. New docking experiments were performed with bonded QS-13, positioning the centres of the grid search on the centre of mass of each PAI. Following this protocol, we were able to identify the residues of the integrin that interacted directly the QS-13 peptides (central and right panel of Fig. 4d). It was interesting to observe that among the residues that made contact with the QS-13 peptide, the aspartic acid residue was one of the most common, followed by glutamic acid, tyrosine and serine. Focusing the contact investigation on the best binding energy structure obtained in the PAI-1 region, we again highlight the fact that the contacts made by QS-13 mostly involved these four types of residues in the protein. Finally, when we compare our docking results with 1L5G PDB structure 20 , we observe that the position of PAI-1 is colocalized with the region of interaction between the RGD peptide and the ...
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... experiments of QS-13 on α V β 3 . For each QS-13 peptide (listed in Fig. 4b), we collected 27000 (180 × 150) structures from the docking experiments. To overcome the bias introduced by the forced explora- tion of empty or unfavourable interaction areas, we kept the first 180 lowest energy structures and studied them in detail. These structures were then spatially regrouped in clusters to allow identification of the most probable interacting surface protein areas. For each QS-13 peptide, we identified the preferred areas of interaction (PAI) with the integrin; at the most, five were identified. In the left panel of Fig. 4d, the five PAIs found with the QS-13-3 peptide (also representative of the results obtained with the other peptides) are shown. Most often for 4 QS-13 peptides out of the 6 investigated through docking, as shown in Fig. 4b, PAI-5 was the area that had the highest frequency (see Table S3). From the energetic point of view, the negative binding energies accounted for the favourable interactions between the QS-13 peptide and this area of α v β 3 . On average, PAI-3 was the least populated area. It was not explored by the QS-13-2 peptide, and in 3 of the 5 experiments, the lowest binding energy did not traduce any favourable interaction since it was close to zero. Other than PAI-3, which could be removed from the potential interacting areas, it seemed difficult to remove the remaining PAI. Looking at the energy, 2 out of the 6 peptides seemed to be very interesting, QS-13-5 and QS-13-6, since they had at least 4 of the lowest binding energies below the threshold of −3.00 kcal/mol. New docking experiments were performed with bonded QS-13, positioning the centres of the grid search on the centre of mass of each PAI. Following this protocol, we were able to identify the residues of the integrin that interacted directly the QS-13 peptides (central and right panel of Fig. 4d). It was interesting to observe that among the residues that made contact with the QS-13 peptide, the aspartic acid residue was one of the most common, followed by glutamic acid, tyrosine and serine. Focusing the contact investigation on the best binding energy structure obtained in the PAI-1 region, we again highlight the fact that the contacts made by QS-13 mostly involved these four types of residues in the protein. Finally, when we compare our docking results with 1L5G PDB structure 20 , we observe that the position of PAI-1 is colocalized with the region of interaction between the RGD peptide and the ...
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... experiments of QS-13 on α V β 3 . For each QS-13 peptide (listed in Fig. 4b), we collected 27000 (180 × 150) structures from the docking experiments. To overcome the bias introduced by the forced explora- tion of empty or unfavourable interaction areas, we kept the first 180 lowest energy structures and studied them in detail. These structures were then spatially regrouped in clusters to allow identification of the most probable interacting surface protein areas. For each QS-13 peptide, we identified the preferred areas of interaction (PAI) with the integrin; at the most, five were identified. In the left panel of Fig. 4d, the five PAIs found with the QS-13-3 peptide (also representative of the results obtained with the other peptides) are shown. Most often for 4 QS-13 peptides out of the 6 investigated through docking, as shown in Fig. 4b, PAI-5 was the area that had the highest frequency (see Table S3). From the energetic point of view, the negative binding energies accounted for the favourable interactions between the QS-13 peptide and this area of α v β 3 . On average, PAI-3 was the least populated area. It was not explored by the QS-13-2 peptide, and in 3 of the 5 experiments, the lowest binding energy did not traduce any favourable interaction since it was close to zero. Other than PAI-3, which could be removed from the potential interacting areas, it seemed difficult to remove the remaining PAI. Looking at the energy, 2 out of the 6 peptides seemed to be very interesting, QS-13-5 and QS-13-6, since they had at least 4 of the lowest binding energies below the threshold of −3.00 kcal/mol. New docking experiments were performed with bonded QS-13, positioning the centres of the grid search on the centre of mass of each PAI. Following this protocol, we were able to identify the residues of the integrin that interacted directly the QS-13 peptides (central and right panel of Fig. 4d). It was interesting to observe that among the residues that made contact with the QS-13 peptide, the aspartic acid residue was one of the most common, followed by glutamic acid, tyrosine and serine. Focusing the contact investigation on the best binding energy structure obtained in the PAI-1 region, we again highlight the fact that the contacts made by QS-13 mostly involved these four types of residues in the protein. Finally, when we compare our docking results with 1L5G PDB structure 20 , we observe that the position of PAI-1 is colocalized with the region of interaction between the RGD peptide and the ...
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... dynamics (MD) simulation of QS-13. The first objective of the MD simulation was to explore and characterize the intrinsic structural behaviour of the investigated peptides, specifically the role of the exper- imentally evidenced disulfide bond and potential key residues. The second objective was to select relevant QS-13 conformations that can be used for docking experiments on integrin α v β 3 . From the different 200 ns NPT sim- ulations performed on a set of 10 different peptides (Supplementary Table S1), clustering analyses allowed us to identify the different types of conformations that occurred along the trajectory. One striking observation was that the presence of the disulfide bond between the 222 C and 225 C was directly responsible for the occurrence of a lower number of clusters (see Supplementary Table S2). Indeed, for the four peptides presenting a disulfide bond, there was at least one division by two of the number of clusters compared to the peptide without the disulfide bond. In addition, the observation and superposition of the MD trajectory showed that the structure of the CQVC portion was almost frozen in the same conformation (Fig. 4a, left panel) for these 4 peptides and that the Q and V middle residues never explored a coil conformation, favouring a bend or a turn local structure. In addition, transitioning from the disulfide bond structure to the structure without the disulfide bond, the increase in the number of clus- ters was accompanied by a decrease in the percentage of structures found in the five first ...
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... the structures with (Fig. 4a, left panel) and without (Fig. 4a, central panel) the disulfide bond, it is quite understandable that since the peptides without the disulfide bond "explore" a larger configuration space, they are characterized by a larger number of clusters. Another interesting feature is illustrated in the right panel of Fig. 4a: not only is the structure of the CQVC portion almost frozen for a given peptide, but by aligning the representative structures (i.e., the first cluster) of the four peptides containing a disulfide bond, we showed that they fit very well and that they almost conserved the same orientation and exposure of the QV and R side chains towards the outside of the ...
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... the structures with (Fig. 4a, left panel) and without (Fig. 4a, central panel) the disulfide bond, it is quite understandable that since the peptides without the disulfide bond "explore" a larger configuration space, they are characterized by a larger number of clusters. Another interesting feature is illustrated in the right panel of Fig. 4a: not only is the structure of the CQVC portion almost frozen for a given peptide, but by aligning the representative structures (i.e., the first cluster) of the four peptides containing a disulfide bond, we showed that they fit very well and that they almost conserved the same orientation and exposure of the QV and R side chains towards the outside of the ...
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... the structures with (Fig. 4a, left panel) and without (Fig. 4a, central panel) the disulfide bond, it is quite understandable that since the peptides without the disulfide bond "explore" a larger configuration space, they are characterized by a larger number of clusters. Another interesting feature is illustrated in the right panel of Fig. 4a: not only is the structure of the CQVC portion almost frozen for a given peptide, but by aligning the representative structures (i.e., the first cluster) of the four peptides containing a disulfide bond, we showed that they fit very well and that they almost conserved the same orientation and exposure of the QV and R side chains towards the outside of the ...
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... different clusters studied below are listed in Fig. 4b. Figure 4c presents the secondary structures of QS-13 first and second clusters of the QS-13 peptide that were used in the docking experiments. From these representa- tions, we observed that the disulfide bond locked CQVC in a conformation that exposed the glutamine side chain. The side chain exposure was explored systematically for all of the MD simulations ( Supplementary Fig. S2). Two factors strongly modified the general profile of the solvent accessible surface (SAS) of the peptide: the loss of the disulfide bond and modification of glutamine, arginine or cysteine residues, especially, when one of the cysteine residues was mutated into ...
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... different clusters studied below are listed in Fig. 4b. Figure 4c presents the secondary structures of QS-13 first and second clusters of the QS-13 peptide that were used in the docking experiments. From these representa- tions, we observed that the disulfide bond locked CQVC in a conformation that exposed the glutamine side chain. The side chain exposure was explored systematically for all of the MD simulations ( Supplementary Fig. S2). Two factors strongly modified the general profile of the solvent accessible surface (SAS) of the peptide: the loss of the disulfide bond and modification of glutamine, arginine or cysteine residues, especially, when one of the cysteine residues was mutated into ...
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... and 225 C of Tetrastatin are crucial for QS-13 binding to SK-MEL-28 cells. Molecular dynamics simulation and docking experiments highlighted the importance of several QS-13 sequences in binding to the α v β 3 integrin. Six substituted peptides labelled with biotin on their C-terminus were synthesized (Fig. 5b). Their binding to SK-MEL-28 cells was evaluated by flow cytometry (Fig. 5c). The different substitutions decreased peptide binding to α v β 3 ( Fig. 5d). Substitution of 222 C and 225 C completely abolished the adhesion and by the way, cell proliferation, migration and invasion ( Supplementary Fig. S3). By mass spectroscopy, we showed that the QS-13 peptide forms an intrachain disulfide bond that appeared to be crucial for QS-13 binding to cell surface. The substitution of 221 R completely abolished the adhesion. The 221 R residue might also be crucial for the binding. QS-13 binding to αvβ3 inhibits FAK, PI3-kinase and Akt phosphorylation. It is now well estab- lished that the FAK/PI 3 K/Akt pathway plays a critical role in the progression of melanoma. To analyse the effects of QS-13 on this transduction pathway, SK-MEL-28 melanoma cells were incubated with the QS-13 peptide for 5, 10, 20, 60 min. The expression of total proteins and their corresponding phosphorylated forms were evaluated by western blotting. The FAK Y397 /total FAK ratio was decreased by 67% at 5 min and 76% at 10 min (Fig. 6a). The PI 3 K p85 Y458 /total PI 3 K p85 ratio decreased gradually from 33% at 5 min to 72% at 60 min (Fig. 6b). The pAkt T308 /total Akt ratio decreased gradually from 46% after 5 min of incubation to 66% after 20 min (Fig. 6c). Taken together, our results demonstrated that the FAK/PI 3 K/Akt pathway is impacted by the QS-13 peptide ( Supplementary Fig. ...
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... the MD experiments, several amino-acids from the QS-13 peptide were suggested to be crucial for the interaction with α v β 3 . These amino-acids were sequentially replaced by an alanine residue, and modified pep- tides were tested for their ability to bind to the SK-MEL-28 cell surface. Substitution of the cysteines at positions 222 and 225 by alanine abolished peptide binding to SK-MEL-28. As suggested by the MD simulation and docking experiments, the disulfide bond was found to be crucial for QS-13 binding to SK-MEL-28 through α v β 3 . Although docking experiments were not performed with the mutated peptides, we can clearly draw a correlation between the results obtained with the MD simulations and observations extracted from the docking results. As stated pre- viously, the MD simulations highlight the importance of the disulfide bond and its role in the structure and the exposure of the side chain groups. In particular, the right panel of Fig. 4a shows the accessibility of the arginine residue, which is a positively charged residue in a physiological environment and was simulated this way. Analysis of the docking indicates that there are two main contacts in term of integrin residues: the aspartate and glutamate residues, which are negatively charged amino acids. We can then postulate that arginine/aspartate or arginine/ glutamate interactions are strong favourable electrostatic interactions that contribute to a better stabilization of the position observed in the case of QS13 peptides containing the disulfide bond since it lowers the value of the binding energy of QS13 to integrin. In summary, QS-13 binding to α v β 3 appears to be conformation-dependent. α v β 3 was reported to differentially activate cell migration and the intracellular signalling FAK/PI 3 K/AKT path- way in a ligand-specific manner 24,25 . FAK (focal adhesion kinase) is a multifunctional protein 26 that is particu- larly involved in tumor invasion 27 . Phosphorylation of the PI 3 K activating subunit (p85) is important, especially because of its role in cell migration and tumor growth 28 Y458 and Akt T308 phosphorylation decreased after QS-13 binding to SK-MEL-28, in agreement with the inhibition of cell migration and invasion that we observed in ...
Citations
... Zgodnie z literaturą, ten typ kolagenu może także wywierać odmienne działanie w tkance nowotworowej. Wykazano bowiem, że jedna z domen kolagenu typu IV posiada anty-nowotworowe właściwości, obniżając proliferację oraz inwazyjność komórek czerniaka [46]. Zawartość tego białka w metastatycznej tkance raka jelita grubego okazuje się być jednak zdecydowanie niższa niż w tkance zdrowej [25]. ...
The phenomenon of drug resistance has been one of the biggest challenges in oncology for many years. Cancer cells develop mechanisms that limit the effectiveness of treatment, affecting the survival rate of cancer patients. Most of those mechanisms are based on higher expression of transmembrane proteins that pump the drug out of the cancer cell. Currently, researchers are focusing more on the interaction between tumor cell and their microenvironment, and the direct involvement of the extracellular matrix in resistance. Many scientific studies have shown that increasing the expression of individual components of the extracellular matrix can limit the availability of the drug to cancer cells. Other mechanisms have also been reported where some drugs become directly bound to individual components of the matrix. Furthermore, cancer cells, by interacting with matrix components, activate transcriptional signals that generate resistance mechanisms. This paper is a review of the knowledge on the participation of selected components of the neoplastic extracellular matrix in the phenomenon of drug resistance. This is a very important issue because a better understanding of this mechanism offers the possibility of developing new therapies that could improve the lives of cancer patients and potentially lead to a cured.
... For example, the proteolytic processing of laminin-332 releases distinct domains, which are capable of engaging a wide variety of receptors on squamous cell carcinomas, such as α6β4 integrin, syndecan-1, and EGFR, to promote cancer cell survival, invasion, and migration (Marinkovich, 2007). However, the role of matrikines is not limited to tumor promotion, as they also exhibit tumor-inhibitory activities (Hamano et al, 2003;Lambert et al, 2018). As examples, collagen-derived matrikines tumstatin and tetrastatin act through the αvβ3 integrin receptor to inhibit angiogenesis-dependent lung carcinoma growth and melanoma progression, respectively (Hamano et al, 2003;Lambert et al, 2018). ...
... However, the role of matrikines is not limited to tumor promotion, as they also exhibit tumor-inhibitory activities (Hamano et al, 2003;Lambert et al, 2018). As examples, collagen-derived matrikines tumstatin and tetrastatin act through the αvβ3 integrin receptor to inhibit angiogenesis-dependent lung carcinoma growth and melanoma progression, respectively (Hamano et al, 2003;Lambert et al, 2018). Although the role of ECM-derived matrikines in the modulation of pathogenesis and progression of solid tumor types is well documented, their role in hematological malignancies, and MM in particular, remains obscure. ...
Multiple myeloma (MM), the second most common hematological malignancy, is generally considered incurable because of the development of drug resistance. We previously reported that hyaluronan and proteoglycan link protein 1 (HAPLN1) produced by stromal cells induces activation of NF-κB, a tumor-supportive transcription factor, and promotes drug resistance in MM cells. However, the identity of the cell surface receptor that detects HAPLN1 and thereby engenders pro-tumorigenic signaling in MM cells remains unknown. Here, we performed an unbiased cell surface biotinylation assay and identified chaperonin 60 (CH60) as the direct binding partner of HAPLN1 on MM cells. Cell surface CH60 specifically interacted with TLR4 to evoke HAPLN1-induced NF-κB signaling, transcription of anti-apoptotic genes, and drug resistance in MM cells. Collectively, our findings identify a cell surface CH60-TLR4 complex as a HAPLN1 receptor and a potential molecular target to overcome drug resistance in MM cells.
... In several studies, it was observed that collagen IV-derived canstatin, tumstatin and tetrastatin, and collagen XIX-derived matrikine act through binding to several integrins, including α3β1, α5β1, or αVβ3. As a result, cellular proliferation and invasion are decreased [82,83]. ...
The extracellular matrix (ECM) is an important component of the tumor microenvironment (TME), having several important roles related to the hallmarks of cancer. In cancer, multiple components of the ECM have been shown to be altered. Although most of these alterations are represented by the increased or decreased quantity of the ECM components, changes regarding the functional alteration of a particular ECM component or of the ECM as a whole have been described. These alterations can be induced by the cancer cells directly or by the TME cells, with cancer-associated fibroblasts being of particular interest in this regard. Because the ECM has this wide array of functions in the tumor, preclinical and clinical studies have assessed the possibility of targeting the ECM, with some of them showing encouraging results. In the present review, we will highlight the most relevant ECM components presenting a comprehensive description of their physical, cellular and molecular properties which can alter the therapy response of the tumor cells. Lastly, some evidences regarding important biological processes were discussed, offering a more detailed understanding of how to modulate altered signalling pathways and to counteract drug resistance mechanisms in tumor cells.
... Focal adhesion kinase (FAK) mediates a signaling cascade that has been implicated in a plethora of human cancers in the context of cell migration and invasion [16,17]. FAK is shown to directly bind to β-subunits of integrins involved in cell adhesion complexes and instigate a range of downstream signaling cascades, including PI3K/AKT [18,19]. In PDAC, overexpression of FAK and its increased phosphorylation at the active site, Tyrosine 397 (Y397), has been previously reported [20]. ...
Elevated levels of Mucin-16 (MUC16) in conjunction with a high expression of truncated O-glycans is implicated in playing crucial roles in the malignancy of pancreatic ductal adenocarcinoma (PDAC). However, the mechanisms by which such aberrant glycoforms present on MUC16 itself promote an increased disease burden in PDAC are yet to be elucidated. This study demonstrates that the CRISPR/Cas9-mediated genetic deletion of MUC16 in PDAC cells decreases tumor cell migration. We found that MUC16 enhances tumor malignancy by activating the integrin-linked kinase and focal adhesion kinase (ILK/FAK)-signaling axis. These findings are especially noteworthy in truncated O-glycan (Tn and STn antigen)-expressing PDAC cells. Activation of these oncogenic-signaling pathways resulted in part from interactions between MUC16 and integrin complexes (α4β1), which showed a stronger association with aberrant glycoforms of MUC16. Using a monoclonal antibody to functionally hinder MUC16 significantly reduced the migratory cascades in our model. Together, these findings suggest that truncated O-glycan containing MUC16 exacerbates malignancy in PDAC by activating FAK signaling through specific interactions with α4 and β1 integrin complexes on cancer cell membranes. Targeting these aberrant glycoforms of MUC16 can aid in the development of a novel platform to study and treat metastatic pancreatic cancer.
... For example, collagen could stimulate angiogenesis in a myocardial infarction model (13). Moreover, collagens have been demonstrated to reduce melanoma cell proliferation and invasion by inhibiting the FAK/PI3K/AKT pathway (14). ...
Preeclampsia is a common obstetric disorder affecting 2-8% of pregnancy worldwide. Fibrosis is an important histological change occurring in preeclamptic placenta, and might depend on the excess deposition of collagen I. However, the role of fibrotic placenta and collagen I in the pathogenesis of preeclampsia remains unclear. Therefore, we analyzed the collagen deposition and the expression of Collagen I in human placenta by Masson staining, Sirius red staining and western blotting. Further, the role of collagen I in preeclampsia pathogenesis was studied in C57BL/6 mice. HTR-8/SVneo cells were used to investigate the mechanisms underlying the effects of collagen I in trophoblasts by transcriptome sequencing and pharmacological agonists. Human preeclamptic placenta exhibited a significantly higher degree of fibrosis in stem villi and terminal villi than normal placenta, and was characterized by collagen I deposition. In vivo, a single injection of collagen I on gestational day 0.5 led to an increase in systolic pressure of pregnant mice from gestational days 4.5–17.5, to a decrease in weight and number of embryos, and to enhanced placental collagen I expression and degree of fibrosis compared with control mice. In vitro, collagen I attenuated the proliferation and invasion of HTR-8SV/neo cells. This effect could be reversed by treatment with agonists of ERK and β-catenin. Moreover, transcriptome sequencing demonstrated that signaling pathways related to cell proliferation and invasion were significantly downregulated in HTR-8SV/neo cells. Thus, we propose that collagen I induced preeclampsia-like symptoms by suppressing the proliferation and invasion of trophoblasts through inhibition of the ERK phosphorylation and WNT/β-catenin signaling pathways. Our findings could pave the way to the discovery of small-molecule inhibitors for preeclampsia treatment and future studies with larger sample size are required.
... We employed the RGD-strategy by using a set of linear and cyclic peptides that have shown promising results as integrinspecific ligands in different formulations, 30 such as cyclo-(RGDf-NMeV) (cilengitide), 31 cyclo(RGDfK), 32 RGDSK, 33 CDCRGDCFC (RGD4C), 34 and QKISRCQVCVKYS (QS13). 35 We first analyzed the interactions of the peptides with the cancer cell receptor through peptide−protein docking using the crystal structure of the extracellular segment of αVβ3 in complex with cilengitide as a reference (PDB ID: 1L5G). 36 Figure 1 shows the docking scores of all 10 000 models generated for each case. ...
... 36 The RGD4C peptide forms hydrogen-bond interactions and salt bridges with some critical residues in the binding site such as D179, D150, and R214 through the side chain or backbone amide of 2 D, 4 R, and 6 D ( Figure 2B). Additional contacts involve a π−π stacking between Y178 and 8 F and a hydrogen bond between Y166 and the carboxylate group of 2 D. As previously reported, 35 although the QS13 peptide does not have an RGD motif, we observed that its binding site on αVβ3 overlaps the RGD binding site. The 5 R 6 C 7 Q 8 V 9 C portion of the peptide stabilizes the interaction with the receptor through a hydrogen-bond network formed between either the side chains or the backbone amide of this sequence motif and some key residues like D150, Y178, D218, I147, and Q145 ( Figure 2C). 2 K also seems to be crucial for the binding mode due to the formation of hydrogen bonds and salt bridges with D126, allowing for the interaction with the β3 subunit together with the hydrogenbond interaction between 1 Q and D251. ...
... The 5 R 6 C 7 Q 8 V 9 C portion of the peptide stabilizes the interaction with the receptor through a hydrogen-bond network formed between either the side chains or the backbone amide of this sequence motif and some key residues like D150, Y178, D218, I147, and Q145 ( Figure 2C). 2 K also seems to be crucial for the binding mode due to the formation of hydrogen bonds and salt bridges with D126, allowing for the interaction with the β3 subunit together with the hydrogenbond interaction between 1 Q and D251. Interestingly, QS13 has been shown to inhibit the focal adhesion kinase (FAK)/ PI3K/Akt pathway, 35 which might confer some additional pharmacological action to the nanosystem for the proposed targeted cancer therapy. On the basis of the predicted potential mechanism of binding, we selected both QS13 and RGD4C peptides as the best candidates for designing the proposed AuNC-based targeted drug delivery system. ...
Nanodrug delivery systems (NDDSs) based on water-soluble and atomically precise gold nanoclusters (AuNCs) are under the spotlight due to their great potential in cancer theranostics. Gastric cancer (GC) is one of the most aggressive cancers with a low early diagnosis rate, with drug therapy being the primary means to overcome its increasing incidence. In this work, we designed and characterized a set of 28 targeted nanosystems based on Au144(p-MBA)60 (p-MBA = para-mercaptobenzoic acid) nanocluster to be potentially employed as combination therapy in GC treatment. The proposed multifunctional AuNCs are functionalized with cytotoxic drugs (5-fluorouracil and epirubicin) or inhibitors of different signaling pathways (phosphatidylinositol 3-kinases (PI3K)/protein kinase B (Akt)/mammalian target of the rapamycin (mTOR), vascular endothelial growth factor (VEGF), and hypoxia-inducible factor (HIF)) and RGD peptides as targeting ligands, and we studied the role of ligand ratio in their optimal structural conformation using peptide–protein docking and all-atom molecular dynamics (MD) simulations. The results reveal that the peptide/drug ratio is a crucial factor influencing the potential targeting ability of the nanosystem. The most convenient features were observed when the peptide amount was favored over the drug in most cases; however, we demonstrated that the system composition and the intermolecular interactions on the ligand shell are crucial for achieving the desired effect. This approach helps guide the experimental stage, providing essential information on the size and composition of the nanosystem at the atomic level for ligand tuning in order to increase the desired properties.
... Under non-pathological conditions, VEGF is expressed mainly in the cytoplasm and on the membranes of vascular endothelial cells (23,24). The expression of VEGF in tumor cells treated with antitumor peptides was lower compared with that in the PBS group, indicating that the peptides could effectively inhibit VEGF expression (25,26). ...
Melanoma is a common malignant skin tumor, which is the only fatal skin tumor at present. Melanoma has a high degree of malignancy and metastasis. The activity of modified Temporin-La (T-La) peptides from bullfrog skin were evaluated for antitumor activity and improved targeting in melanoma cells. The amino acid sequence of T-La was modified, resulting in the antitumor peptide, T-La (FS). T-La and T-La (FS) were coupled to the RGD small molecule polypeptide to form the chimeric peptides RGD-T-La and RGD-T-La (FS), respectively. The secondary structures for the peptides, evaluated using circular dichroism, were found to be α-helical. The structure of T-La was evaluated using bioinformatics. In addition, the antitumor effects of the modified peptide and the targeting of RGD chimeric peptide to the tumor in vivo and in vitro were analyzed. Antitumor activity was measured in vitro using the MTT assay. Tumor cells with high integrin αvβ3 expression were detected using flow cytometry, and tumor cells were screened for sensitivity to RGD-T-La (FS) to establish a tumor model in nude mice. The effects of the peptides on tumor cells were measured using laser confocal microscopy in real-time. The mechanism of the peptide antitumor activity in tumor cells was evaluated with scanning electron microscopy. B16 melanoma cells were the most sensitive to the peptides, for which the cell survival rate was 24.65% for 10 µg/ml RGD-T-La (FS). RGD-La (FS) had a rapid effect on tumor cells. RGD chimeric polypeptides exhibited site-targeting cytotoxic effects in tumor cells. In the B16 melanoma mouse model, the peptides exhibited antitumor effects against early melanoma development and induced tumor apoptosis, possibly by inhibiting VEGF and promoting caspase-3 expression. Overall, the present study provides a scientific basis for the application of small molecule antimicrobial peptides as targeted antitumor agents and lays the foundation for the clinical application of these peptides as antitumor drugs.
... In addition to cytotoxic approaches, integrin-based therapies can inhibit metastatic traits. Examples include Tetrastatin, the NC1 domain of collagen IV, and antibodies targeting tetraspanins-a family of transmembrane proteins involved in integrin heterodimer scaffolding known to contribute to cell adhesion properties (85,86). Tangentially, the BRAFi vemurafenib was found to suppress metastasis, at least in part, by acting through the PGC1a-ID2-TCF4-integrin axis (87) and targeting ILK has shown preclinical efficacy (35). ...
Prior to metastasis, modern therapeutics and surgical intervention can provide a favorable long-term survival for patients diagnosed with many types of cancers. However, prognosis is poor for patients with metastasized disease. Melanoma is the deadliest form of skin cancer, yet in situ and localized, thin melanomas can be biopsied with little to no postsurgical follow-up. However, patients with metastatic melanoma require significant clinical involvement and have a 5-year survival of only 34% to 52%, largely dependent on the site of colonization. Melanoma metastasis is a multi-step process requiring dynamic changes in cell surface proteins regulating adhesiveness to the extracellular matrix (ECM), stroma, and other cancer cells in varied tumor microenvironments. Here we will highlight recent literature to underscore how cell adhesion molecules (CAM) contribute to melanoma disease progression and metastasis.
... They also pointed out the inhibitory effects of Tetrastatin-2 and Pentastatin-3, two peptides from the α4(IV) and α5(IV) NC1 domains, respectively, on VEGF-induced HUVEC migration We previously demonstrated the potent antitumor activity of the α4(IV) NC1 domain, named Tetrastatin (Brassart-Pasco et al., 2012). We recently identified the minimal active sequence (QKISRCQVCVKYS: QS-13) of Tetrastatin that reproduced whole Tetrastatin anti-tumor properties in vivo and in vitro on melanoma cell proliferation, migration, and invasion (Lambert et al., 2018). ...
... Docking of QS-13 onto α 5 β 1 integrin (RCSB Protein Data Bank 3VI3) was performed using Autodock software (version 4.2; Morris et al., 2009). The docking parameters were as previously described (Lambert et al., 2018). The software was used with a fixed integrin and semi-flexible QS-13 ligand (the backbone was frozen as well as the amide links and guanidinium groups). ...
... Each box was divided along the three directions, and the distance between the nodes was equal to 0.375 Å. The Lamarckian genetic algorithm was used, and for each ligand, 150 dockings were performed with the default parameters of Autodock except for the population size (150), number of energy evaluations (5 × 10 6 ), and maximum number of generations (30,000; Lambert et al., 2018). Molecular models were derived from the preliminary study. ...
Angiogenesis is defined as the formation of new capillaries by sprouting from the pre-existing microvasculature. It occurs in physiological and pathological processes particularly in tumor growth and metastasis. α1, α2, α3, and α6 NC1 domains from type IV collagen were reported to inhibit tumor angiogenesis. We previously demonstrated that the α4 NC1 domain from type IV collagen, named Tetrastatin, inhibited tumor growth in a mouse melanoma model. The inhibitory activity was located in a 13 amino acid sequence named QS-13. In the present paper, we demonstrate that QS-13 decreases VEGF-induced-angiogenesis in vivo using the Matrigel plug model. Fluorescence molecular tomography allows the measurement of a 65% decrease in Matrigel plug angiogenesis following QS-13 administration. The results are confirmed by CD31 microvessel density analysis on Matrigel plug slices. QS-13 peptide decreases Human Umbilical Vein Endothelial Cells (HUVEC) migration and pseudotube formation in vitro. Relevant QS-13 conformations were obtained from molecular dynamics simulations and docking. A putative interaction of QS-13 with α5β1 integrin was investigated. The interaction was confirmed by affinity chromatography, solid phase assay, and surface plasmon resonance. QS-13 binding site on α5β1 integrin is located in close vicinity to the RGD binding site, as demonstrated by competition assays. Collectively, our results suggest that QS-13 exhibits a mighty anti-angiogenic activity that could be used in cancer treatment and other pathologies with excessive angiogenesis such as hemangioma, psoriasis or diabetes.
... the focal adhesion kinase (FAK)/PI3K/Akt/mTORC1 pathway, which is one of the main intracellular pathways involved in TME metabolic alterations. The inhibition leads to a decrease in the proliferative and invasive properties of tumor cells in various cancer models (27,33,38,56). The main receptors, biological activities, and molecular mechanisms identified for ECM bioactive fragments are reported in Table 1 and are illustrated in Figure 2. ...
The tumor microenvironment (TME) is composed of various cell types embedded in an altered extracellular matrix (ECM). ECM not only serves as a support for tumor cell but also regulates cell–cell or cell–matrix cross-talks. Alterations in ECM may be induced by hypoxia and acidosis, by oxygen free radicals generated by infiltrating inflammatory cells or by tumor- or stromal cell-secreted proteases. A poorer diagnosis for patients is often associated with ECM alterations. Tumor ECM proteome, also named cancer matrisome, is strongly altered, and different ECM protein signatures may be defined to serve as prognostic biomarkers. Collagen network reorganization facilitates tumor cell invasion. Proteoglycan expression and location are modified in the TME and affect cell invasion and metastatic dissemination. ECM macromolecule degradation by proteases may induce the release of angiogenic growth factors but also the release of proteoglycan-derived or ECM protein fragments, named matrikines or matricryptins. This review will focus on current knowledge and new insights in ECM alterations, degradation, and reticulation through cross-linking enzymes and on the role of ECM fragments in the control of cancer progression and their potential use as biomarkers in cancer diagnosis and prognosis.
