Long non-coding RNA XIST is down-regulated and correlated to better prognosis in ovarian cancer.

Ovarian cancer (OC) is one of the most common gynecological malignant tumors. Understanding the molecular mechanisms involved in the development of ovarian cancer is helpful for the diagnosis and treatment of OC. In this study, we found that lncRNA XIST was significantly overexpressed in normal ovarian tissues and down-regulated in OC. Moreover, we showed XIST was associated with the development of OC and down-regulated in advanced stage OC compared to early-stage OC samples. Overexpression of XIST was significantly associated with longer survival in patients with OC. Also, our analysis also showed that lncRNA XIST was closely related to biological processes such as transcription, protein phosphorylation, transport, protein ubiquitination, and DNA repair. To further reveal the function and role of XIST in OC, we constructed a protein-protein interaction network and an endogenous competitive RNA network. The present study provided a theoretical basis for the diagnosis and treatment of OC.

Construction of a catsper1 DNA vaccine and its antifertility effect on male mice.

Cation channel of sperm 1 (CATSPER1) is a unique sperm cation channel protein, and essential for sperm function and male fertility. CATSPER1 exclusively expresses in meiotic and postmeiotic spermatogenic cells, thus belongs to the spermatogenesis-specific antigen that escape central tolerance. We have previously demonstrated the immunocontraceptive potential of its transmembrane domains and pore region, and reported the antifertility effects of its B-cell epitopes on male mice. Aiming to develop DNA vaccine targeting CATSPER1 for male contraception, here the whole open reading frame of mouse Catsper1 was cloned into the plasmid pEGFP-N1 to obtain a DNA vaccine pEGFP-N1-Catsper1. The vaccine was confirmed to be transcribed and translated in mouse N2a cell in vitro and mouse muscle tissue in vivo. Intramuscular injection with the vaccine on male mice induced specific immune reaction and caused significant inhibition on sperm hyperactivated motility and progressive motility (P<0.001 for both), and consequently reduced male fertility. The fertility rate of experimental group was 40.9%, which was significant lower (P=0.012) than control group (81.8%). No significant change in mating behavior, sperm production and histology of testis/epididymis was observed. Given that Catsper1 exhibits a high degree of homology among different species, Catsper1 DNA vaccine might be a good strategy for developing an immunocontraceptive vaccine for human and animal use.