Chaoyang Sun's research while affiliated with Tongji Hospital and other places

Limited understanding exists regarding how aging impacts the cellular and molecular aspects of the human ovary. This study combines single-cell RNA sequencing and spatial transcriptomics to systematically characterize human ovarian aging. Spatiotemporal molecular signatures of the eight types of ovarian cells during aging are observed. An analysis of age-associated changes in gene expression reveals that DNA damage response may be a key biological pathway in oocyte aging. Three granulosa cells subtypes and five theca and stromal cells subtypes, as well as their spatiotemporal transcriptomics changes during aging, are identified. FOXP1 emerges as a regulator of ovarian aging, declining with age and inhibiting CDKN1A transcription. Silencing FOXP1 results in premature ovarian insufficiency in mice. These findings offer a comprehensive understanding of spatiotemporal variability in human ovarian aging, aiding the prioritization of potential diagnostic biomarkers and therapeutic strategies.

Introduction/Background Endometrial cancer (EC) is the most common gynaecological cancer in high income countries and its incidence is rising globally. Genetic susceptibility of EC have been linked with several loci of common variants, however, these only explained ~10% genetic background and the overall contribution of rare coding variants to EC is unclear. Methodology Here, we performed exome-wide association study to evaluate the penetrance of rare coding variants on cross-ancestry datasets. The UK Biobank conprised of 1,587 EC cases and 159,324 non-cancer controls from Gaussian ancestry. Burden tests from the STAAR pipeline were applied to identify novel genes with excess pathogenic loss-of-function (pLOF) and disruptive missense (d-mis) variants in EC. We replicated these results on in house Chinese EC cohort of 239 patients compared with 10,588 Chinese controls from ChinaMAP. In vitro experients were used to assess effects of these genes. Results Associations between pLOF as well as pLOF plus d-mis (pLOF_ds) variants and EC identified 50 and 26 genes at exome-wide significance (p < 2.5*10–6), respectively, including known EC susceptibility genes MSH6 and MSH2. These results were replicated in Chinese cohort, revealing X genes also contributing to EC in East Asia population. In vitro silence of these genes through small interfering RNA (siRNA) suggested that functional silence of these genes would result in decreased proliferation rates and migration capacity. Conclusion We uncovered novel EC risk genes across European and Asia population and validated their functions. This would provide new insights on genetic background of EC and pave the way for screening of EC. Disclosures The authors declare no competing interests.

Introduction/Background Ovarian cancer is a heterogeneous disease with perplexing pathogenesis mechanism and prevention strategies are limited. Pelvic inflammatory disease (PID) has been suggested to increase the risk of developing ovarian cancer (OC), but existing literature have been inconclusive and large prospective cohort studies are inadequate. Methodology We conducted a prospective cohort study of 261624 women participants in the UK Biobank. During a median of 12.8 years of follow-up, we included 901 incident OC cases. Germline homologous recombination (gHR) mutations carriers were determined using paired whole-exome-sequencing data. We used Cox’s regression models to assess the hazard ratios (HRs) of risk of developing OC under PID, with adjustment for confunding factors. We also conducted subgroup analysis by tumor histology subtyping and age. The interactive effect of gHR and PID history was determined using cox regressions. Results We identified 4054 women with PID and 257570 controls in this large prospective cohort study. Among participants 901 had developed ovarian cancer during a median of 12.8 years follow-up period. The adjusted hazard ratio for ovarian cancer in patients with PID was 1.45 (95% CI 0.90–2.32) compared with controls. However, in the age subgroup analysis, we found a positive relation between history of PID and risk of OC in aged younger than 55 years (1.92, 95% CI 1.02–3.63). Furthermore, participants who had a PID history and gHR mutations have the highest risk of developing OC (7.40, 95% CI 1.03–53.10). Conclusion In our study, we found that PID is a potential precursor for ovarian cancer, especially in participants aged younger than 55 years with gHR mutation, as participants who had a PID history and HRD mutations have the highest risk of developing OC. The mechanism between genetic susceptibility, PID and OC remains still obscure and needs to be further investigated. Disclosures The authors declare no competing interests.

Introduction/Background Ovarian cancer is an aggressive disease characterized by extensive intraperitoneal dissemination. However, the mechanisms underlying the facilitation of metastasis within site-specific microenvironments remain unknown. Methodology We analyzed approximately paired 60 whole genome- and bulk RNA-sequencing, ~ 150, 000 of single cells and two million spots of spatial transcriptomics (ST) data to profile site-specific microenvironment and cell-cell contact in situ. We conducted in vitro and in vivo experiments to confirm phenotypes and validate our hypothesis. Results We unveiled a spatiotemporal landscape of ovarian cancer, elucidating the roles of metastatic units (MU), comprised of tripartite ensemble of MMP11+ myCAFs, epithelial cells and SPP1+ macrophages, in promoting tumor spread. In vitro and in vivo experiments indicated that MU could be targeted and disrupted by gene X and gene Y inhibition. We observed dynamic conversions on ST, with immune-activated cell neighborhoods in ovaries transitioning to stromal-like in metastases. Moreover, utilizing our newly designed STARLETS framework, we elucidated a Darwinian evolutionary process driven by hypoxia and immune selections occurring in the ovary while selected clone subsequently migrated to liver. Conclusion Our results provided novel insights into the mechanisms of metastasis and offered a foundation for further investigations into the co-evolution of tumors and host systems, as well as treatments that target the interplay between malignant tumors and immune cells in ascites. Disclosures The authors have no competing interests.

5520 Background: First-line treatments for locally advanced cervical cancer (LACC) have limited efficacy and neoadjuvant chemotherapy (NACT) is an emerging approach, however, two-thirds of patients (pts) respond to it and pts without response benefit little. PD-1 inhibitors have shown promising role in recurrent or metastatic cervical cancer. This study aims to evaluate the efficacy and safety of preoperative PD-1 inhibitor camrelizumab combined neoadjuvant therapy for LACC. Methods: The study is designed as a multicenter, open-label, single-arm, prospective phase II study. Pts are enrolled if they had previously untreated LACC (2018 FIGO staged IB3, IIA2 and IIB/IIIC1r (tumor size > 4cm). Eligible pts will receive neoadjuvant chemo-immunotherapy (NACIT), defined as one cycle of cisplatin (75-80 mg/m2, iv) plus nab-paclitaxel (260 mg/m2, iv) NACT and subsequent two cycles of camrelizumab (200mg, iv) combined NACT. Either surgery or concurrent chemoradiotherapy are conducted according to the response as per the Response Evaluation Criteria In Solid Tumors (RECIST) version 1.1. The primary endpoint was objective response rate (ORR), and the secondary endpoints were pathological complete remission (pCR) rate, rate of postoperative adjuvant treatment, event-free survival, overall survival and safety. Results: From Dec 1, 2020 to Feb 1, 2023, 83 pts were enrolled, and 78 pts were evaluated for response. The ORR was 100% (95%CI, 95.38 to 100), with 14 (17.95%) complete response (CR) and 64 (82.05%) partial response. Regarding the pathological findings of 76 pts who underwent radical surgery, 30 (39.47% (95%CI, 28.44 to 51.35)) pts achieved pCR, while 17 (22.37%) needed postoperative adjuvant treatment as indicated in NCCN guideline, of who 14 had positive pelvic nodes, positive surgical margin, and/or positive parametrium and the other three met Sedlis criteria. RECIST CR was significantly associated with pCR ( P = 0.016). Pre-treatment PD-L1 expression (Combined Positive Score) was a predictive biomarker for RECIST CR ( P = 0.036) but not for pCR ( P = 0.078) in these evaluated patients. Grade 3 or 4 treatment-related adverse events occurred in 35 (44.87%) pts during NACIT; the most common were lymphocytopia (25.64%), neutropenia (12.82%) and leucopenia (8.97%). Conclusions: NACIT for LACC demonstrated extremely high ORR and pCR rate with manageable toxicity profile, and greatly reduced the need of postoperative adjuvant therapy. Clinical trial information: NCT04516616 .

Although Poly (ADP-ribose) polymerase (PARP) inhibitors (PARPi) have been approved in multiple diseases, including BRCA1/2 mutant breast cancer, responses are usually transient thus requiring the deployment of combination therapies that can prevent or reverse PARPi resistance. We thus explored mechanisms underlying sensitivity and resistance to PARPi using two intrinsically sensitive and resistant syngeneic murine breast cancer models. Our data indicate that the PARPi-sensitive tumor model has a high ratio of M1 anti-tumor/M2 pro-tumor macrophages with the M1/M2 ratio being increased by PARPi. In contrast the PARPi-resistant tumor model had very low levels of M1 macrophages and thus a low M1/M2 ratio that was not altered by PARPi. Transplantation of the PARPi-sensitive and the PARPi-resistant tumor in opposite mammary fat pads results in accumulation of M2 macrophages in the sensitive tumor, rendering the sensitive tumor PARPi resistant suggesting that transit of M2 macrophages could contribute to resistance across distant sites both within and between tumors. C5ar1 and Rps19/C5ar1 signaling are selectively elevated in the M2 macrophages that are associated with PARPi resistance. Indeed, C5aR1 positive cells were sufficient to transfer resistance to PARPi. Strikingly targeting C5aR1 decreased M2 macrophage numbers, while sparing M1 macrophages rendering PARPi-resistant tumors sensitive to PARPi in a CD8 T cell dependent manner. Consistent with the murine data, high C5aR1 levels in human breast cancers are associated with a poor response to immune checkpoint blockade. Thus, targeting C5aR1 may represent an approach to selectively deplete M2 macrophages and engender sensitivity to PARPi and potentially other therapies.

Although Poly (ADP-ribose) polymerase (PARP) inhibitors' resistance has gradually become a major challenge in the maintenance therapy for high-grade serous ovarian carcinoma (HGSOC), there are no universal indicators for resistance monitoring in patients. A key resistance mechanism to PARP inhibitors (PARPis) is the restoration of homologous recombination repair (HRR), including BRCA reversion mutations and changes in DNA damage repair proteins. To explore mutation profiles associated with PARPis' resistance, we performed targeted 42-gene deep sequencing of circulating cell-free DNA (cfDNA) extracted from pre-treatment and post-treatment in HGSOC patients with Olaparib maintenance therapy. We found that pathogenic germline mutations in the HRR pathway, including BRCA1/2, were strongly associated with improved clinical outcomes, and newly acquired MRE11A mutations significantly shortened the progression-free survival (PFS) of patients. Furthermore, dynamic fluctuations of somatic mutation sites in CHEK2:p.K373E and CHEK2:p.R406H can be used for evaluating the therapeutic efficacy of patients. MRE11A:p.K464R may be a vital driving factor of Olaparib resistance, which patients who newly acquired MRE11A:p.K464R in post-treatment cfDNA had significantly shorter PFS than those without it. These findings provide potential noninvasive biomarkers for efficacy evaluation and resistance monitoring of Olaparib treatment, and lay the foundation for developing combination treatment after Olaparib resistance.

Our understanding of how aging affects the cellular and molecular components of the human ovary and contributes to age-related fertility decline is still limited. Here, we link single-cell RNA sequencing and spatial transcriptomics to characterize human ovarian aging. Changes of the molecular signatures of eight types of ovarian cells during aging were defined. We combined single cell types with their spatial location information to divide ovarian granulosa cells into three subtypes and theca & stroma cells into five subtypes. Further analysis revealed increased cellular senescence with age and characterized the transcription factor FOXP1 as a master regulatory gene during ovarian aging. Inhibition of FOXP1 in ovarian cells increased cellular senescence which was alleviated by pharmacological treatment with quercetin or fisetin. These findings provide a comprehensive understanding of the spatiotemporal variability of human ovarian aging, providing resources for developing new diagnostic biomarkers and therapeutic strategies against ovarian aging.