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| CDK7 inhibitors affected MCF-7 cell survival. (A) The cell viability was detected by the CCK8 assay after MCF-7 cells were treated with increasing concentrations of LDC4297 for 24 or 48 h separately. (B, D) The colony formation ability was detected after MCF-7 cells were treated with THZ1 or LDC4297. (C, E) Quantitation of colony formation ability in (B) and (D) separately. (F) Apoptosis was analyzed by flow cytometry after MCF-7 cells were treated with 50 nM THZ1 or LDC4297 2.5 μM for 24 h. (G) Quantity of apoptosis in (F). Statistically significant: *p < 0.05; **p < 0.01.
Source publication
Higher cyclin-dependent kinase (CDK7) expression is a character of breast cancer and indicates poor prognosis. Inhibiting CDK7 exhibited effective cancer cell suppression which implies the potential of CDK7 inhibition to be a method for anti-cancer treatment. Our study aimed to explore a novel mechanism of CDK7 inhibition for suppressing breast can...
Contexts in source publication
Context 1
... CCK8 results showed that although the survival of MCF-7 cells was not significantly affected by treatment with low concentrations of THZ1, the repressive effect could still be detected in a dose-and time-dependent manner, confirming previous results ( Peng et al., 2021). As shown in Figure 1A, LDC4297 also suppressed tumor growth. The colony formation assay revealed that CDK7 inhibitors attenuated the tumor stem cell characteristics of MCF-7 cells (Figures 1B-E). ...
Context 2
... shown in Figure 1A, LDC4297 also suppressed tumor growth. The colony formation assay revealed that CDK7 inhibitors attenuated the tumor stem cell characteristics of MCF-7 cells (Figures 1B-E). Additionally, the results of the flow cytometry analysis confirmed that apoptosis occurred in MCF-7 cells treated for 24 h with THZ1 and LDC4297 ( Figures 1F,G). ...
Context 3
... colony formation assay revealed that CDK7 inhibitors attenuated the tumor stem cell characteristics of MCF-7 cells (Figures 1B-E). Additionally, the results of the flow cytometry analysis confirmed that apoptosis occurred in MCF-7 cells treated for 24 h with THZ1 and LDC4297 ( Figures 1F,G). Both THZ1 and LDC4297 suppressed MCF-7 cells by slowing down cell proliferation and inducing apoptosis, which implied the potential breast tumor suppressive effect of CDK7 inhibitors. ...
Context 4
... caspase-3 is a GSDME cleavage trigger, and this study aimed to detect GSDME in fulllength form, ZR-71-1 was chosen for its lack of both caspase 3 expression and p53 mutations ( Keyomarsi and Pardee, 1993;Devarajan et al., 2002). The repression of breast cancer cell proliferation and colony formation was observed following CDK7 inhibition treatment (Figures 1, 6), identifying CDK7 inhibitors as potential agents for breast cancer treatment. Studies confirm CDK7 silencing blocks RNAP II-CTD phosphorylation ( Galbraith et al., 2019), and RNAP IIhypophosphorylation-induced suppression of transcription initiation and elongation can elevate p53 protein levels and accumulation in the nucleus by phosphorylating the p53 Ser-15 site (Derheimer et al., 2007). ...
Citations
... Analysis of TCGA ER-positive (ER+) breast cancer samples has revealed a positive correlation between CDK7 and ER mRNA levels, and high CDK7 expression has been associated with notably shorter OS for ER+ breast cancer patients [72]. Experimental approaches targeting CDK7 through specific small molecular inhibitors, such as THZ1 [72], LDC4297 [73], ICEC0942 [45], SNS-032 [74], and roscovitine [75], have proven effective in suppressing ER+ breast cancer cells. Specifically, these treatments have been demonstrated to inhibit the proliferation of ER+ breast cancer cells, induce apoptosis, and suppress the growth of breast cancer xenografts in murine models [45,[72][73][74]. ...
... Experimental approaches targeting CDK7 through specific small molecular inhibitors, such as THZ1 [72], LDC4297 [73], ICEC0942 [45], SNS-032 [74], and roscovitine [75], have proven effective in suppressing ER+ breast cancer cells. Specifically, these treatments have been demonstrated to inhibit the proliferation of ER+ breast cancer cells, induce apoptosis, and suppress the growth of breast cancer xenografts in murine models [45,[72][73][74]. Most remarkably, the combination of CDK7 inhibitors with known therapeutic agents like fulvestrant [45] or tamoxifen [72,75] has shown enhanced efficacy in inhibiting tumor growth compared to either single agent, highlighting the potential therapeutic advantage of these combinations. ...
Cyclin-dependent kinase 7 (CDK7) serves as a pivotal regulator in orchestrating cellular cycle dynamics and gene transcriptional activity. Elevated expression levels of CDK7 have been ubiquitously documented across a spectrum of malignancies and have been concomitantly correlated with adverse clinical outcomes. This review delineates the biological roles of CDK7 and explicates the molecular pathways through which CDK7 exacerbates the oncogenic progression of breast cancer. Furthermore, we synthesize the extant literature to provide a comprehensive overview of the advancement of CDK7-specific small-molecule inhibitors, encapsulating both preclinical and clinical findings in breast cancer contexts. The accumulated evidence substantiates the conceptualization of CDK7 as a propitious therapeutic target in breast cancer management.
... 126 Breast cancer cell proliferation and colony formation are negatively impacted by CDK7 inhibition in a p53-GSDME-dependent manner. 127 Several investigations have found that different chemotherapy drugs can stimulate distinct pyroptosis pathways. Cisplatin enhances complete response rates in patients with triple-negative breast cancer patients by activating the lncRNA MEG3/NLRP3/caspase 1/GSDMD pyroptosis pathway. ...
Nonprogrammed cell death (NPCD) and programmed cell death (PCD) are two types of cell death. Cell death is significantly linked to tumor development, medication resistance, cancer recurrence, and metastatic dissemination. Therefore, a comprehensive understanding of cell death is essential for the treatment of cancer. Pyroptosis is a kind of PCD distinct from autophagy and apoptosis in terms of the structure and function of cells. The defining features of pyroptosis include the release of an inflammatory cascade reaction and the expulsion of lysosomes, inflammatory mediators, and other cellular substances from within the cell. Additionally, it displays variations in osmotic pressure both within and outside the cell. Pyroptosis, as evidenced by a growing body of research, is critical for controlling the development of inflammatory diseases and cancer. In this paper, we reviewed the current level of knowledge on the mechanism of pyroptosis and inflammasomes and their connection to cancer and inflammatory diseases. This article presents a theoretical framework for investigating the potential of therapeutic targets in cancer and inflammatory diseases, overcoming medication resistance, establishing nanomedicines associated with pyroptosis, and developing risk prediction models in refractory cancer. Given the link between pyroptosis and the emergence of cancer and inflammatory diseases, pyroptosis‐targeted treatments may be a cutting‐edge treatment strategy.
... In terms of the biological function of GSDME, Kim et al. conducted cell proliferation and invasion assays in vitro and revealed that GSDME acts as a tumor suppressor [57]. Consistently, Wang et al. also identified that CDK7 inhibition induced the expression of GSDME in a p53-dependent pathway, thus inhibiting breast cancer cell growth and promoting cell death [62]. ...
Pyroptosis is a lytic and inflammatory type of programmed cell death that is mediated by Gasdermin proteins (GSDMs). Attractively, recent evidence indicates that pyroptosis involves in the development of tumors and can serve as a new strategy for cancer treatment. Here, we present a basic knowledge of pyroptosis, and an overview of the expression patterns and roles of GSDMs in breast cancer. In addition, we further summarize the available evidence of pyroptosis in breast cancer progression and give insight into the clinical potential of applying pyroptosis in anticancer strategies for breast cancer. This review will deepen our understanding of the relationship between pyroptosis and breast cancer, and provide a novel potential therapeutic avenue for breast cancer.
... Enhanced generation of ROS could induce GSDME activation, and promote pyroptosis in TNBC [36,37] . Breast cancer suppressor p53 could activate GSDME and inhibit CDK7 to suppress breast cancer survival [38] . In vivo, anti-tumor immunity could be stimulated through GSDME activation [20] , suggesting an advanced anti-tumor potential of GSDMD and GSDME in breast cancer. ...
Triple-negative breast cancer (TNBC) is a massive threat to women's health due to its high morbidity, malignancy, and the refractory, effective therapeutic option of TNBC is still deficient. The mitochondrial protein showed therapeutic potential on breast cancer, whereas the mechanism and downstream pathway of mitochondrial uncoupling protein 1 (UCP1) was not fully elucidated. We found that UCP1 was negatively regulated to the process of TNBC. Overexpressing UCP1 could inhibit the proliferation and metastasis of TNBC, meanwhile inducing the mitochondrial swelling and activation of mitophagy in vitro. Mitophagy activation was then assessed to elucidate whether it was downstream of UCP1 in TNBC metastasis. GSDME is the core of pyroptosis. We found that GSDME was activated in the TNBC cells when UCP1 levels were high. It regulates TNBC cell proliferation potential instead of the apoptosis process in vitro and in vivo. Our results suggested that UCP1 could inhibit the process of TNBC by activating mitophagy and pyroptosis. Impaired activation of mitophagy weakens the regulation effect of UCP1 on metastasis of TNBC, similar to the impairment of GSDME activation on the proliferation regulation of UCP1 on TNBC. UCP1 might be a novel therapeutic target of TNBC.
... However, the pathogenic process of BC involves a complex effect of multifactor, multistage, and multistep [4], which makes different patients have different reactions to treatment accompanied by a certain strong adverse reaction. In biology, target treatment at molecular level can not only allow us to further tailor therapies for cancer but also avoid developing strong adverse reaction or even reach no side effects [5]. Therefore, it is a current focus of the cancer research field. ...
This study mainly explores how miR-183-5p pertains to breast cancer (BC) development. Functional assays were employed to test impacts of miR-183-5p in this cancer. Targeting between RGS2 and miR-183-5p was examined with dual-luciferase assay, and how their interaction pertains to cancer progression was further unraveled. miR-183-5p level was noticeably high in cancer tissue/cells. Overexpressing miR-183-5p could remarkably deteriorate cancer progression. The regulatory gene RGS2 levels was markedly low in BC, and two genes we researched were negatively correlated. It was uncovered by rescue assay that miR-183-5p/RGS2 axis mediated tumor-relevant behaviors in BC. Altogether, miR-183-5p aggravates BC development via mediation of RGS2. miR-183-5p supplies a promising target for BC therapy.
Gasdermin (GSDM) family, the key executioners of pyroptosis, play crucial roles in anti-pathogen and anti-tumor immunities, although little is known about the expression of GSDM in lung diseases at single-cell resolution, especially in lung epithelial cells. We comprehensively investigated the transcriptomic profiles of GSDM members in various lung tissues from healthy subjects or patients with different lung diseases at single cell level, e.g., chronic obstructive pulmonary disease (COPD), idiopathic pulmonary fibrosis (IPF), lung adenocarcinoma (LUAD), or systemic sclerosis (SSC). The expression of GSDM members varied among pulmonary cell types (immune cells, structural cells, and especially epithelial cells) and even across lung diseases. Regarding disease-associated specificities, we found that GSDMC or GSDMD altered significantly in ciliated epithelia of COPD or LUAD, GSDMD in mucous, club, and basal cells of LUAD and GSDMC in mucous epithelia of para-tumor tissue, as compared with the corresponding epithelia of other diseases. The phenomic specificity of GSDM in lung cancer subtypes was noticed by comparing with 15 non-pulmonary cancers and para-cancer samples. GSDM family gene expression changes were also observed in different lung epithelial cell lines (e.g., HBE, A549, H1299, SPC-1, or H460) in responses to external challenges, including lipopolysaccharide (LPS), lysophosphatidylcholine (lysoPC), cigarette smoking extract (CSE), cholesterol, and AR2 inhibitor at various doses or durations. GSDMA is rarely expressed in those cell lines, while GSDMB and GSDMC are significantly upregulated in human lung epithelia. Our data indicated that the heterogeneity of GSDM member expression exists at different cells, pathologic conditions, challenges, probably dependent upon cell biological phenomes, functions, and behaviors, upon cellular responses to external changes, and the nature and severity of lung disease. Thus, the deep exploration of GSDM phenomes may provide new insights into understanding the single-cell roles in the tissue, regulatory roles of the GSDM family in the pathogenesis, and potential values of biomarker identification and development.
Graphical Abstract
Background
The cyclin-dependent kinase 7 (CDK7) inhibitor THZ1 represses multiple cancer cells. However, its tumor-repressive efficiency in wild-type p53 breast cancer cells remains controversial.
Methods
We conducted various assays, including CCK8, colony formation, flow cytometry, western blotting, and lactate dehydrogenase release detection, to clarify whether p53 elevation sensitizes breast cancer cells to THZ1.
Results
We found that upregulating functional p53 contributes to the increased sensitivity of breast cancer cells to THZ1. Increased THZ1 sensitivity requires active p53 and an intact p53 pathway, which was confirmed by introducing exogenous wild-type p53 and the subsequent elevation of THZ1-mediated tumor suppression in breast cancer cells carrying mutant p53. We confirmed that p53 accumulates in the nucleus and mitochondria during cell death. Furthermore, we identified extensive transcriptional disruption, rather than solely CDK7 inhibition, as the mechanism underlying the nutlin-3 and THZ1-induced death of breast cancer cells. Finally, we observed the combined nutlin-3 and THZ1 treatment amplified gasdermin E cleavage.
Conclusion
Enhanced sensitivity of breast cancer cells to THZ1 can be achieved by increasing effective p53 expression. Our approach may serve as a potential treatment for patients with breast cancer resistant to regular therapies.
GSDMD and GSDME, members of the gasdermin protein family, are involved in the formation of plasma membrane channels contributing to cell rupture during a certain type of necrosis called pyroptosis. GSDMD is activated in response to immunological stimulation such as lipopolysaccharides (LPS) treatment while GSDME is mainly involved in drug-induced tumor cell death. Here we show that the expression of the GSDMD gene increases significantly during LPS-induced pyroptosis in RAW264.7 murine macrophage cells. In contrast, GSDME expression is decreased in the same cells. The increasing effect of LPS on GSDMD expression was observed only when the cells were cultured in high glucose (4.5 g/l) medium, suggesting that glucose availability is important for this effect. The effect of LPS on GSDMD expression is abolished by 2-deoxyglucose (2DG), confirming that glycolysis plays crucial roles in the increasing effect of LPS. Small interference RNA-mediated knock down of GSDMD or overexpression of GSDME causes LPS-induced pyroptosis to take place through GSDME rather than through GSDMD. Taken together, LPS regulates GSDMD and GSDME expression in opposite directions through, at least in part, its effect on glycolysis. This transcriptional regulation may contribute to the execution of pyroptosis in a GSDMD-dependent manner.
