Circular RNA circMAN1A2 promotes ovarian cancer progression through the microRNA-135a-3p/IL1RAP/TAK1 pathway.

Background: Ovarian cancer (OC) is the most lethal malignancy in women owing to its diagnosis only at the advanced stage. Elucidation of its molecular pathogenesis may help identify new tumor markers and targets for therapy. Circular RNAs (circRNAs) are stable, conserved, and functional biomolecules that can be used as effective biomarkers for various cancers. Methods: In this study, a potential circRNA related to early diagnosis of OC, circMAN1A2, was analyzed. Overexpression/knockdown of circMAN1A2 in OC cells was used to decipher its effects on cell proliferation with a Cell Counting Kit-8, 5-ethynyl-2'-deoxyuridine (EdU), cell cycle, clone formation, and wound healing assay. RNA pull-down and Dual luciferase assay were used to explain the underlying mechanism by which circMAN1A2 regulates OC cell proliferation. In vivo, the effect of circMAN1A2 in OC was evaluated using nude mouse xenograft experiments. Results: CircMAN1A2 was highly expressed in OC and promoted proliferation, clone formation, and tumorigenicity of OC cells. In addition, we found that circMAN1A2 acted as a sponge for microRNA (miR)-135a-3p; miR-135a-3p directly targeted the 3' untranslated region of interleukin 1 receptor accessory protein (IL1RAP) in OC cells, thereby regulating the phosphorylation of transforming growth factor-beta activated kinase 1 (TAK1), which resulted in promotion of OC cell growth. Conclusions: CircMAN1A2 promotes OC cell proliferation by inhibiting the miR-135a-3p/IL1RAP/TAK1 axis. In conclusion, circMAN1A2 may be a biomarker for early detection of OC and a target for subsequent therapy.

Human Papillomavirus Genome-Wide Identification of T-Cell Epitopes for Peptide Vaccine Development Against Cervical Cancer: An Integration of Computational Analysis and Experimental Assay.

Human papillomavirus (HPV) has long been documented as the primary factor causing cervical cancer and other complications, and development of immunotherapeutic vaccines against HPV is thought to be an important approach in preventing women from HPV infections. It is known that the first step in vaccine development is to find potent T-cell epitopes in HPV proteins that can be effectively recognized and presented by the human leukocyte antigen (HLA) system. In the current study, we proposed a synthetic pipeline that integrates computational analysis and experimental assay to discover new peptide epitopes from HPV genome with high affinity to the HLA-A*0201, one of the most frequent HLA allele in Caucasian and Asian populations. In the procedure, a structure-based three-dimensional quantitative structure-activity relationship (3D-QSAR) methodology was described and several 3D-QSAR predictors were established using a set of activity-known HLA binders. The best predictor was then employed to perform extrapolation over the HPV genome to screen potential protein fragments with high HLA binding potency. Consequently, 10 peptides were suggested as promising candidates and their affinities toward HLA-A*0201 were assayed using a standard T2 cell surface stabilization test. Four peptides--LLITSNINA from protein E1 (BL50 = 7244 nM), VLLCVCLLI from protein E5 (BL50 = 9118 nM), VLLLWITAA from protein E5 (BL50 = 3388 nM), and LLMGTLGIV from protein E7 (BL50 = 5500 nM)--were identified as high-affinity binders. Further, the structural basis and binding mode of HLA-A*0201-LLITSNINA complex was examined in detail, revealing a complicated network of nonbonded interactions across the complex interface that should render high stability and specificity for the interaction system.