Delivery of SIRT1 by cancer-associated adipocyte-derived extracellular vesicles regulates immune response and tumorigenesis of ovarian cancer cells

Purpose This study intends to investigate the possible molecular mechanism of immune response and tumorigenesis in ovarian cancer cells, mediated by sirtuin 1 (SIRT1)-containing extracellular vesicles (EVs) derived from cancer-associated adipocytes (CAAs) (CAA-EVs). Methods Differentially expressed genes in EVs from CAAs were screened by RNA transcriptome sequencing, and the downstream pathway was predicted in silico. The binding between SIRT1 and CD24 was investigated by luciferase activity and ChIP-PCR assays. EVs were extracted from human ovarian cancer tissue-isolated CAAs, and the internalization of CCA-EVs by ovarian cancer cells was characterized. The ovarian cancer cell line was injected into mice to establish an animal model. Flow cytometry was performed to analyze the proportions of M1 and M2 macrophages, CD8+ T, T-reg, and CD4+ T cells. TUNEL staining was used to detect cell apoptosis in the mouse tumor tissues. ELISA detection was performed on immune-related factors in the serum of mice. Results CAA-EVs could deliver SIRT1 to ovarian cancer cells, thereby affecting the immune response of ovarian cancer cells in vitro and promoting tumorigenesis in vivo. SIRT1 could transcriptionally activate the expression of CD24, and CD24 could up-regulate Siglec-10 expression. CAA-EVs-SIRT1 activated the CD24/Siglec-10 axis and promoted CD8+ T cell apoptosis, thereby promoting tumorigenesis in mice. Conclusion CAA-EVs-mediated transfer of SIRT1 regulates the CD24/Siglec-10 axis to curb immune response and promote tumorigenesis of ovarian cancer cells (AU)

Delivery of SIRT1 by cancer-associated adipocyte-derived extracellular vesicles regulates immune response and tumorigenesis of ovarian cancer cells.

PURPOSE: This study intends to investigate the possible molecular mechanism of immune response and tumorigenesis in ovarian cancer cells, mediated by sirtuin 1 (SIRT1)-containing extracellular vesicles (EVs) derived from cancer-associated adipocytes (CAAs) (CAA-EVs). METHODS: Differentially expressed genes in EVs from CAAs were screened by RNA transcriptome sequencing, and the downstream pathway was predicted in silico. The binding between SIRT1 and CD24 was investigated by luciferase activity and ChIP-PCR assays. EVs were extracted from human ovarian cancer tissue-isolated CAAs, and the internalization of CCA-EVs by ovarian cancer cells was characterized. The ovarian cancer cell line was injected into mice to establish an animal model. Flow cytometry was performed to analyze the proportions of M1 and M2 macrophages, CD8+ T, T-reg, and CD4+ T cells. TUNEL staining was used to detect cell apoptosis in the mouse tumor tissues. ELISA detection was performed on immune-related factors in the serum of mice. RESULTS: CAA-EVs could deliver SIRT1 to ovarian cancer cells, thereby affecting the immune response of ovarian cancer cells in vitro and promoting tumorigenesis in vivo. SIRT1 could transcriptionally activate the expression of CD24, and CD24 could up-regulate Siglec-10 expression. CAA-EVs-SIRT1 activated the CD24/Siglec-10 axis and promoted CD8+ T cell apoptosis, thereby promoting tumorigenesis in mice. CONCLUSION: CAA-EVs-mediated transfer of SIRT1 regulates the CD24/Siglec-10 axis to curb immune response and promote tumorigenesis of ovarian cancer cells.

LINC01119 encapsulated by cancer-associated adipocytes-derived exosomes promotes M2 polarization of macrophages to induce immune escape in ovarian cancer in a 3D co-culture cell-based model

Introduction In the present study, we sought to clarify the role of LINC01119 delivered by cancer-associated adipocytes (CAAs)-derived exosomes (CAA-Exo) and its mechanistic actions in ovarian cancer (OC). Materials and methods The expression of LINC01119 was determined in OC, and the relationship between LINC01119 expression and the prognosis of OC patients was analyzed. Besides, 3D co-culture cell models were constructed using green fluorescent protein-labeled OC cells and red fluorescent protein-labeled mature adipocytes. Mature adipocytes were co-cultured with OC cells to induce CAA. Macrophages treated with CAA-Exo were co-cultured with SKOV3 cells following ectopic expression and depletion experiments of LINC01119 and SOCS5 to detect M2 polarization of macrophages, PD-L1 level, proliferation of CD3+ T cells, and cytotoxicity of T cells to SKOV3 cells. Results LINC01119 was elevated in the plasma Exo of OC patients, which was related to shorter overall survival in OC patients. LINC01119 expression was increased in CAA-Exo, which could upregulate SOCS5 in OC. Finally, CAA-Exo carrying LINC01119 induced M2 polarization of macrophages to promote immune escape in OC, as evidenced by inhibited CD3+ T cell proliferation, increased PD-L1 level, and attenuated T cell toxicity to SKOV3 cells. Conclusion In conclusion, the key findings of the current study demonstrated the promoting effects of CAA-Exo containing LINC01119 mediating SOCS5 on M2 polarization of macrophages and immune escape in OC (AU)

LINC01119 encapsulated by cancer-associated adipocytes-derived exosomes promotes M2 polarization of macrophages to induce immune escape in ovarian cancer in a 3D co-culture cell-based model.

INTRODUCTION: In the present study, we sought to clarify the role of LINC01119 delivered by cancer-associated adipocytes (CAAs)-derived exosomes (CAA-Exo) and its mechanistic actions in ovarian cancer (OC). MATERIALS AND METHODS: The expression of LINC01119 was determined in OC, and the relationship between LINC01119 expression and the prognosis of OC patients was analyzed. Besides, 3D co-culture cell models were constructed using green fluorescent protein-labeled OC cells and red fluorescent protein-labeled mature adipocytes. Mature adipocytes were co-cultured with OC cells to induce CAA. Macrophages treated with CAA-Exo were co-cultured with SKOV3 cells following ectopic expression and depletion experiments of LINC01119 and SOCS5 to detect M2 polarization of macrophages, PD-L1 level, proliferation of CD3+ T cells, and cytotoxicity of T cells to SKOV3 cells. RESULTS: LINC01119 was elevated in the plasma Exo of OC patients, which was related to shorter overall survival in OC patients. LINC01119 expression was increased in CAA-Exo, which could upregulate SOCS5 in OC. Finally, CAA-Exo carrying LINC01119 induced M2 polarization of macrophages to promote immune escape in OC, as evidenced by inhibited CD3+ T cell proliferation, increased PD-L1 level, and attenuated T cell toxicity to SKOV3 cells. CONCLUSION: In conclusion, the key findings of the current study demonstrated the promoting effects of CAA-Exo containing LINC01119 mediating SOCS5 on M2 polarization of macrophages and immune escape in OC.

Hsa_circ_0000520 overexpression increases CDK2 expression via miR-1296 to facilitate cervical cancer cell proliferation.

BACKGROUND: Circular RNA (circRNA) has been demonstrated to participate in cervical cancer development. In this study, we analyzed the role of hsa_circ_0000520 in cervical cancer. METHODS: Fifty-two pairs of cervical cancer and adjacent normal tissue samples were collected, and five human cervical cancer cell lines were obtained followed by the detection of hsa_circ_0000520 expression. Nuclear-cytoplasmic isolation and fluorescence in situ hybridization were performed to analyze the subcellular localization of hsa_circ_0000520 while linear RNA was digested by RNase R. Gain- or loss-of function experiments on hsa_circ_0000520 were performed, followed by detection of cell proliferation and cell cycle by EdU, Cell Counting Kit-8, colony formation assay, and flow cytometry respectively. RESULTS: Hsa_circ_0000520 and cyclin-dependent kinase 2 (CDK2) were highly expressed in cervical cancer tissues. Binding sites between microRNA-1296 (miR-1296) and hsa_circ_0000520 or CDK2 were verified. Antibody to Argonaute 2 (Ago2) could precipitate hsa_circ_0000520, indicating that hsa_circ_0000520 could competitively bind to miR-1296 via Ago2. Silencing hsa_circ_0000520 inhibited cervical cancer cell proliferation and promoted the inhibitory effects of miR-1296 on CDK2, thereby blocking cell cycle progression and promoting apoptosis. CONCLUSION: These results support the premise that targeting hsa_circ_0000520 can be a potential approach to combat cervical cancer.

Overexpression of microRNA-367 inhibits angiogenesis in ovarian cancer by downregulating the expression of LPA1.

BACKGROUND: Compelling evidences reported the role of microRNAs (miRNAs) in ovarian cancer. However, little was known regarding the molecular mechanism of miR-367 in ovarian cancer. This study intended to investigate the role and regulatory mechanism of miR-367 in ovarian cancer involving lysophosphatidic acid receptor-1 (LPA1). METHODS: Potentially regulatory miRNAs in ovarian cancer were obtained from bioinformatics analysis. RT-qPCR was used to detect miR-367 expression in both ovarian cancer tissues and relevant adjacent normal tissues. Relationship between miR-367 and LPA1 was predicted by miRNA database and further verified using dual luciferase reporter gene assay and RIP. EdU and Transwell assay were used to measure the proliferation and invasion ability of cells. Moreover, tube formation and chick chorioallantois membrane (CAM) assay were performed to determine angiogenesis of human umbilical vein endothelial cells (HUVECs). Finally, the roles of LPA1 in tumor growth was also studied using nude mice xenograft assay. RESULTS: High expression of LPA1 and low expression of miR-367 were observed in ovarian cancer tissues and cells. Overexpressed miR-367 downregulated LPA1 expression to inhibit proliferation, invasion, and angiogenesis of cancer cells. Low expression of LPA1 suppressed tumor formation and repressed angiogenesis in ovarian in vivo. CONCLUSION: All in all, overexpression of miR-367 downregulated LPA1 expression to inhibit ovarian cancer progression, which provided a target for the cancer treatment.