Prevalent copy number alteration (CNA) is the most prominent genetic characteristic associated with ovarian cancer (OV) development, but its role in immune evasion has not been fully elucidated. In this study, we identified RAD21, a key component of the cohesin complex, as a frequently amplified oncogene that could modulate immnue response in OV. Through interrogating RAD21-regulated transcriptional program we found that RAD21 directly interacts with YAP/TEAD4 transcriptional co-repressors and recruits NuRD complex to suppress interferon (IFN) signaling. In multiple clinical cohorts, RAD21 overexpression is inversely correlated with IFN signature gene expression in OV. We further demonstrated in murine syngeneic tumor models that RAD21 ablation potentiated anti-PD-1 efficacy with increased intratumoral CD8+ T-cell effector activity. Our study identified a previously unrecognized RAD21-YAP/TEAD4-NuRD co-repressor complex in immune modulation, and thus provided a potential target and biomarker for precision immunotherapy in OV.

Background Uterine leiomyosarcoma (ULMS) is a malignant tumor found in the smooth muscle lining the walls of the uterus. Cancer stem cells (CSCs) are responsible for metastasis, drug resistance, and relapse of cancer, resulting in treatment failure. However, little is known about CSCs and their associated-markers in ULMS. We aimed to characterize and identify a subpopulation of CD133+ cancer stem-like cells derived from SK-UT-1 cell line. Methods SK-UT-1 cells were sphere-forming cultured in vitro. We also sorted the CD133+ cells derived from SK-UT-1 cell line by immunomagnetic beads. CD133+ subpopulation and apoptotic cells were detected by flow cytometry. Self-renewal and anchorage-independent growth capabilities were examined using sphere and colony formation assays. The tumorigenicity of the fourth-passage spheres and parental SK-UT-1 cells was used by mouse xenograft model in vivo. Cell proliferation ability and sensitivity to doxorubicin (DXR) were assessed by CCK-8 assay. Cell migration and invasion were tested by wound healing assay or Transwell migration and invasion assays. Expressions of CSC-related marker were analyzed by Western blotting. Results The fourth-passage spheres were defined as a CD133+ cell population, which was accompanied by increase of sphere and colony forming rate, migration and invasion abilities, as well as drug-resistant properties in vitro. Moreover, the fourth-passage spheres showed a stronger tumorigenic potential in vivo. CD133+ cell population sorted from SK-UT-1 line showed an increased ability in sphere and colony formation, proliferation, migration, invasion, resistance to apoptosis after treatment with doxorubicin (DXR) compared with CD133− cell population. The expression levels of CSCs-related markers (e.g., CD44, ALDH1,BMI1, and Nanog), were significantly elevated in CD133+ cells compared with those in CD133− cells. Conclusions Collectively, our findings indicated that CD133 may be a significant marker for cancer stem-like cells, and it may be a potential therapeutic target for human ULMS.

Acquired resistance to chemotherapy is one of the major causes of mortality in advanced nasopharyngeal carcinoma (NPC). However, effective strategies are limited and the underlying molecular mechanisms remain elusive. In this study, through transcriptomic profiling analysis of 23 tumor tissues, we found that NOTCH3 was aberrantly highly expressed in chemoresistance NPC patients, with NOTCH3 overexpression being positively associated with poor clinical outcome. Mechanistically, using an established NPC cellular model, we demonstrated that enhancer remodeling driven aberrant hyperactivation of NOTCH3 in chemoresistance NPC. We further showed that NOTCH3 upregulates SLUG to induce chemo-resistance of NPC cells and higher expression of SLUG have poorer prognosis. Genetic or pharmacological perturbation of NOTCH3 conferred chemosensitivity of NPC in vitro and overexpression of NOTCH3 enhanced chemoresistance of NPC in vivo. Together, these data indicated that genome-wide enhancer reprogramming activates NOTCH3 to confer chemoresistance of NPC, suggesting that targeting NOTCH3 may provide a potential therapeutic strategy to effectively treat advanced chemoresistant NPC.

Background: To establish a functional monoclonal antibody library using Human Uterine Sarcoma Stem Cell-Like Cells (HUSSLCs) to screen and identify functional monoclonal antibodies that can recognize and inhibit HUSSLCs.Methods: B lymphocytes in proliferative state were prepared by using the second generation CD133+spheroid cells of SK-UT-1 cell line, i.e. HUSSLCs, as antigens; Spheroid formation, agar colony formation, wound healing, flow cytometry, and Western blotting were adopted to detect the effect of monoclonal antibodies with varied dilution ratios on HUSSLCs spheroid formation, agar colony formation, cell migration, CD133 expression, and expression of CD44, ABCG2, Bmi1, Nanog, Oct4 and ALDH1.Results: Myeloma cells of SP2/0 cell line can achieve 85% degrees of fusion and results of 1-2F monoclonal cell supernatants with different dilution ratios reduced HUSSLCs spheroid formation rate, agar colony formation rate, cell migration rate, CD133 positive cell expression and protein expression levels of CD44, ABCG2, Bmi1, Nanog, Oct4, and ALDH1 in concentration-dependent manner (P <0.05).Conclusion: The antibody valence produced by HUSSLCs-immunized mice reached the requirement for preparation of monoclonal antibody. Anti-HUSSLCs monoclonal antibodies feature functions of inhibiting the self-renewal, unrestricted proliferation, migration, invasion and multidrug resistance of HUSSLCs and functions characterized by tumor stem cells.

Background: To establish a functional monoclonal antibody library using Human Uterine Sarcoma Stem Cell-Like Cells (HUSSLCs) to screen and identify functional monoclonal antibodies that can recognize and inhibit HUSSLCs. Methods: B lymphocytes in proliferative state were prepared by using the second generation CD133+spheroid cells of SK-UT-1 cell line, i.e. HUSSLCs, as antigens; Spheroid formation, agar colony formation, wound healing, flow cytometry, and Western blotting were adopted to detect the effect of monoclonal antibodies with varied dilution ratios on HUSSLCs spheroid formation, agar colony formation, cell migration, CD133 expression, and expression of CD44, ABCG2, Bmi1, Nanog, Oct4 and ALDH1. Results: Myeloma cells of SP2/0 cell line can achieve 85% degrees of fusion and results of 1-2F monoclonal cell supernatants with different dilution ratios reduced HUSSLCs spheroid formation rate, agar colony formation rate, cell migration rate, CD133 positive cell expression and protein expression levels of CD44, ABCG2, Bmi1, Nanog, Oct4, and ALDH1 in concentration-dependent manner (P <0.05). Conclusion: The antibody valence produced by HUSSLCs-immunized mice reached the requirement for preparation of monoclonal antibody. Anti-HUSSLCs monoclonal antibodies feature functions of inhibiting the self-renewal, unrestricted proliferation, migration, invasion and multidrug resistance of HUSSLCs and functions characterized by tumor stem cells. Key words: uterine leiomyosarcoma; tumor stem cell; monoclonal antibody; self-renewal ability; infinite multiplication; drug resistance