Xin Li

A positive feedback loop of SRSF9/USP22/ZEB1 promotes the progression of ovarian cancer

Ovarian cancer (OC) is recognized as the most lethal type of gynecological malignancy, making treatment options challenging. Discovering novel therapeutic targets will benefit OC patients. This study aimed to reveal the mechanism by which SRSF9 regulates OC progression. Cell proliferation was determined via CCK-8 assays, whereas cell migration and invasion were monitored via Transwell assays. Western blotting and qPCR assays were used to detect protein and mRNA alterations. RNA pull-down, RNA immunoprecipitation (RIP), and actinomycin D experiments were performed to investigate the relationships between SRSF9 and USP22. Co-IP was used to validate the interaction between USP22 and ZEB1. Chromatin immunoprecipitation (ChIP) and dual-luciferase reporter assays were used to verify the regulatory effect of ZEB1 on the transcription of SRSF9. Subcutaneous xenograft models were established to evaluate the impact of SRSF9 on tumor development. Knockdown of SRSF9 significantly suppressed the proliferation, invasion, migration, tumorigenicity, and epithelial‒mesenchymal transition (EMT) of OC cells. SRSF9 can bind to USP22 mRNA, increasing its stability. Moreover, the overexpression of USP22 reversed the impact of SRSF9 silencing on malignant phenotypes. USP22 can mediate the deubiquitination of ZEB1, thereby enhancing the progression of OC. Furthermore, ZEB1 upregulated SRSF9 expression through transcriptional activation, thus establishing a positive feedback loop. SRSF9 enhanced the malignant characteristics of OC through a positive feedback loop of SRSF9/USP22/ZEB1. This functional circuit may help in the development of novel therapeutic approaches for treating OC.

YTHDF3 suppresses interferon-stimulated gene (ISG)-dependent antitumor immunity and promotes HPV carcinogenesis in cervical cancer

Abstract Interferon-stimulated genes (ISGs) serve as evolutionarily conserved mediators of antiviral defense and tumor surveillance. Emerging evidence underscores the non-oncogenic addiction of high-risk human papillomavirus (hrHPV) E6/E7 oncoproteins in maintaining malignant phenotypes and cervical carcinogenesis. Here, we leveraged CRISPR/Cas9-engineered YTHDF3-knockout (YTHDF3 −/− ) SiHa cells and Ythdf3 −/ − mice to dissect the molecular arbiters governing m 6 A-dependent RNA regulation in HPV-driven carcinogenesis. To further elucidate the role of YTHDF3 in HPV-induced immunosuppressive tumor microenvironment (ITME) formation, we demonstrated that YTHDF3, an m 6 A RNA reader, suppresses type I ISGs responses. Notably, elevated m 6 A modification and YTHDF3 protein levels were observed in HPV + CCa tissues. Mechanistically, YTHDF3 bound to the m 6 A methylation site of STAT3 mRNA, enhancing its stability and transcription efficiency. This YTHDF3-STAT3 axis repressed ISG (e.g., IRF7) transcription and IFN-α production, thereby compromising antiviral immunity and facilitating HPV E6/E7 persistence. Correspondingly, Ythdf3 − mice bearing TC-1 xenografts exhibited a significant reduction in immunosuppressive immune cell infiltration, including Tregs, M2 macrophages, and MDSCs, accompanied by enhanced CD8 + T cell activation. Collectively, our findings unveiled that YTHDF3-mediated upregulation of STAT3 suppresses the type I ISG expression, thus promoting HPV carcinogenesis and establishing an ITME. Taken together, our results suggest that targeting the YTHDF3/STAT3/IRF7 axis could be a promising therapeutic strategy against HPV-associated malignancies.

IFI16 Induced by p53 Activates the NF‐κB Pathway to Counteract Cisplatin‐Induced Apoptosis in Cervical Cancer Cells

ABSTRACTCervical cancer ranks as the second most prevalent cancer among women worldwide, and the primary treatment for advanced cases involves cisplatin‐based chemotherapy. However, the duration of cisplatin treatment is typically short, with a median survival rate of approximately 1 year. This highlights the urgent need to enhance our understanding of cisplatin's mechanism of action in cervical cancer treatment. Our findings demonstrate that p53 induces the nuclear translocation of IFI16, leading to activation of the NF‐κB signalling pathway. This activation plays a crucial role in protecting cervical cancer cells against cisplatin‐induced apoptosis. The activation of NF‐κB is independent of STING, which is a downstream molecule of IFI16. STING signalling activation by cisplatin may not be associated with cisplatin‐induced apoptosis. To further validate this tumour‐promoting effect of IFI16 during cisplatin therapy, we established a subcutaneous implantation tumour model using mouse cervical cancer (U14) cells and conducted additional in vitro experiments. We examined the role and mechanism of IFI16 in cisplatin treatment of cervical cancer. The role of IFI16 in cervical cancer progression deserves further study. Targeted inhibition of IFI16 may be a new way to increase cisplatin sensitivity of cervical cancer cells.

Bepotastine Sensitizes Ovarian Cancer to PARP Inhibitors through Suppressing NF-κB–Triggered SASP in Cancer-Associated Fibroblasts

Abstract Therapy-induced senescence (TIS) is common in tumor cells treated with PARP inhibitors (PARPis) and can serve as a promising target for improving PARPi efficacy. However, whether stromal components within the tumor microenvironment undergo TIS caused by PARPis and contribute to consequential treatment failure remain unclear. We previously revealed that PARPis triggered a senescence-like secretory phenotype in stromal fibroblasts. Here, we further explored PARPi-induced senescence in the stroma, its contribution to PARPi resistance, and opportunities to leverage stromal TIS for improved PARPi sensitivity. In this study, we demonstrated that tumor tissues from patients treated with neoadjuvant PARPis showed a significant senescence-like phenotype in the stroma. Moreover, PARPi-induced senescent cancer-associated fibroblasts (CAFs) displayed a senescence-associated secretory phenotype (SASP) profile that was sufficient to induce tumor resistance to PARPis in both homologous recombination–deficient (HRD) and –proficient ovarian cancer cells. Using the GLAD4U database, we found that bepotastine, an approved H1-antihistamine, inhibited the SASP of PARPi-primed CAFs at clinical serum concentrations. We further demonstrated that bepotastine attenuated fibroblast-facilitated tumor resistance to PARPis in three-dimensional organotypic cultures and HRD-positive patient-derived xenograft models. Mechanistically, bepotastine suppressed PARPi-triggered SASP by inhibiting NF-κB signaling independent of the histamine H1 receptor. Taken together, our results highlight the importance of stromal TIS and SASP in PARPi resistance, and targeting SASP with bepotastine may be a promising therapeutic option for improving PARPi sensitivity in ovarian cancer.

Safe and efficient 2D molybdenum disulfide platform for cooperative imaging-guided photothermal-selective chemotherapy: A preclinical study

The striking imbalance between the ever-increasing amount of nanomedicines and low clinical translation of products has become the focus of intense debate. For clinical translation, the critical issue is to select the appropriate agents and combination regimen for targeted diseases, not to prepare increasingly complex nanoplatforms. A safe and efficient platform, α-tocopheryl succinate (α-TOS) married 2D molybdenum disulfide, was devised by a facile method and applied for cooperative imaging-guided photothermal-selective chemotherapy of ovarian carcinoma. A novel platform of PEGylated α-TOS and folic acid (FA) conjugated 2D MoS The photothermal efficiency (65.3%) of the platform under safe near-infrared irradiation is much higher than that of other photothermal materials reported elsewhere. Moreover, the covalently linked α-TOS renders platform with selective chemotherapy for cancer cells. Remarkably, with these excellent properties, the platform can be used to completely eliminate the solid tumor by safe photothermal therapy, and then kill the residual cancer cells by selective chemotherapy to prevent tumor recurrence. More significantly, barely side effects occur in the whole treatment process. The excellent efficacy and safety benefits The safe and efficient platform might be a candidate of clinical nanomedicines for multimode theranostics. This study demonstrates an innovative thought in precise nanomedicine regarding the design of next generation of cancer theranostic protocol for potential clinical practice.

A Computationally Virtual Histological Staining Method to Ovarian Cancer Tissue by Deep Generative Adversarial Networks

Histological analysis to tissue samples is elemental for diagnosing the risk and severity of ovarian cancer. The commonly used Hematoxylin and Eosin (H&E) staining method involves complex steps and strict requirements, which would seriously impact the research of histological analysis of the ovarian cancer. Virtual histological staining by the Generative Adversarial Network (GAN) provides a feasible way for these problems, yet it is still a challenge of using deep learning technology since the amounts of data available are quite limited for training. Based on the idea of GAN, we propose a weakly supervised learning method to generate autofluorescence images of unstained ovarian tissue sections corresponding to H&E staining sections of ovarian tissue. Using the above method, we constructed the supervision conditions for the virtual staining process, which makes the image quality synthesized in the subsequent virtual staining stage more perfect. Through the doctors’ evaluation of our results, the accuracy of ovarian cancer unstained fluorescence image generated by our method reached 93%. At the same time, we evaluated the image quality of the generated images, where the FID reached 175.969, the IS score reached 1.311, and the MS reached 0.717. Based on the image-to-image translation method, we use the data set constructed in the previous step to implement a virtual staining method that is accurate to tissue cells. The accuracy of staining through the doctor’s assessment reached 97%. At the same time, the accuracy of visual evaluation based on deep learning reached 95%.

A novel homeostatic loop of sorcin drives paclitaxel-resistance and malignant progression via Smad4/ZEB1/miR-142-5p in human ovarian cancer

AbstractThe primary chemotherapy of ovarian cancer (OC) often acquires chemoresistance. Sorcin (SRI), a soluble resistance-related calcium-binding protein, has been reported to be an oncogenic protein in cancer. However, the molecular mechanisms of SRI regulation and the role and aberrant expression of SRI in chemoresistant OC remain unclear. Here, we identified SRI as a key driver of paclitaxel (PTX)-resistance and explored its regulatory mechanism. Using transcriptome profiles, qRT-PCR, proteomics, Western blot, immunohistochemistry, and bioinformatics analyses, we found that SRI was overexpressed in PTX-resistant OC cells and the overexpression of SRI was related to the poor prognosis of patients. SRI was a key molecule required for growth, migration, and PTX-resistance in vitro and in vivo and was involved in epithelial–mesenchymal transition (EMT) and stemness. Mechanistic studies showed that miR-142-5p directly bound to the 3ʹ-UTR of SRI to suppress its expression, whereas a transcription factor zinc-finger E-box binding homeobox 1 (ZEB1) inhibited the transcription of miR-142-5p by directly binding to the E-box fragment in the miR-142 promoter region. Furthermore, ZEB1 was negatively regulated by SRI which physically interacted with Smad4 to block its translocation from the cytosol to the nucleus. Taken together, our findings unveil a novel homeostatic loop of SRI that drives the PTX-resistance and malignant progression via Smad4/ZEB1/miR-142-5p in human OC. Targeting this SRI/Smad4/ZEB1/miR-142-5p loop may reverse the PTX-resistance.

Annexin A5 suppression promotes the progression of cervical cancer

Cervical cancer is a common malignant gynecological disease that threatens the health of women all over the world. The abnormal expression of Annexin A5 (ANXA5) is closely related to the biological behavior of various malignant tumors, however, the relationship between ANXA5 and cervical cancer is still unclear. Therefore, the effects of low expression of ANXA5 on the proliferation, apoptosis, migration and invasion of cervical cancer cells (HeLa) and its related mechanism were explored. The cells were divided into three groups: ANXA5-si group, negative control group and blank group. RNA interference was used to suppress ANXA5 expression. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, colony formation assay, flow cytometry and propidium iodide (PI) staining, wound healing assay and transwell assay were employed to detect cell proliferation, apoptosis, migration and invasion respectively. Meanwhile, gene expression was detected by qPCR and Western blotting. ANXA5 suppression lead to the increase of proliferation, migration, invasion and the decrease of apoptosis of cervical cancer HeLa cells. Furthermore, the expression of both pPI3K and pAkt increased. ANXA5 might inhibit Hela cells proliferation and metastasis by regulating PI3K/Akt signal pathway.

Hypoxia-responsive micelles deprive cofactor of stearoyl-CoA desaturase-1 and sensitize ferroptotic ovarian cancer therapy

Ferroptosis has been recognized as a promising therapeutic strategy for cancer due to its unique mechanism of action. However, the upregulation of stearoyl-CoA desaturase 1 (SCD1) in ovarian cancer leads to resistance to ferroptotic therapy. Zinc ion (Zn