Ferroptosis is a newly identified form of nonapoptotic regulated cell death characterized by iron-dependent accumulation of lipid reactive oxygen species. Morphologically and biochemically different from known types of cell death and apoptosis, ferroptosis promotes nervous system diseases, renal failure, ischemia–reperfusion injury, and the treatment of tumors. It could be induced by several mechanisms, including inhibition of glutathione peroxidase 4, lack of cysteine, and peroxidation of polyunsaturated fatty acids, but could be inhibited by iron chelators, lipophilic antioxidants, and some specific inhibitors. Ferroptosis is found to be closely related to the tumorigenesis, invasion, and metastasis of tumors. Noncoding RNAs (ncRNAs), including long noncoding RNAs (lncRNAs), microRNAs, and circular RNAs, do not encode proteins. NcRNAs are found to be capable of regulating the molecular mechanism of ferroptosis in tumor cells post transcription. Ferroptosis provides a new method for cancer treatment. Although several studies have confirmed the important role of ferroptosis in cancer treatment, its specific affecting mechanism is unclear. Here we reviewed the molecular mechanism of ferroptosis in tumor cells and the relationship between ferroptosis and the three important ncRNAs.

No abstract

Circular RNAs (circRNAs) play important roles in cancer tumorigenesis and progression, representing prognostic biomarkers and therapeutic targets. In this case, we demonstrated the role of circ-NOLC1 in epithelial ovarian cancer (EOC). Our results have shown that Circ-NOLC1 expression was higher in EOC tissues than in normal tissues, and was positively associated with FIGO stage, differentiation. Among ovarian cancer cell lines, circ-NOLC1 expression was the highest in A2780, and lowest in CAOV3. Overexpression of circ-NOLC1 in CAOV3 cells increased cell proliferation, migration, and invasion ability, whereas silencing of circ-NOLC1 in A2780 cells had the opposite effect: however, neither circ-NOLC1 downregulation nor overexpression influenced NOLC1 mRNA expression. In nude mice with subcutaneous tumors, circ-NOLC1 downregulation decreased tumor growth. Bioinformatic analysis and RNA-binding protein immunoprecipitation showed that circ-NOLC1 could bind to ESRP1. In addition, the overexpression of circ-NOLC1 significantly increased ESRP1, RhoA, and CDK1 protein and mRNA expression level; circ-NOLC1 downregulation had the opposite effects. The tumor-promoting effect of circ-NOLC1 was inhibited by knockdown of ESRP1, CDK1, or RhoA expression in circ-NOLC1-overexpressing cells, which might act by modulating RhoA and CDK1 expression. In conclusion, our study demonstrated that Circ-NOLC1 might promote EOC tumorigenesis and development by binding ESRP1 and modulating CDK1 and RhoA expression.

Background. Endometrial cancer is associated with a high mortality rate, which warrants the identification of novel diagnostic markers and therapeutic targets. The aim of this study is to evaluate the role of SNORD15B in the development of endometrial cancer and explore the potential underlying mechanisms. Methods. Bioinformatics was used to analyze the expression level and prognostic relevance of SNORD15B in endometrial cancer. The Ishikawa and HEC-1B cells were respectively transfected with SNORD15B expression plasmid and an antisense oligonucleotide, or the corresponding empty vector and a nonspecific sequence. The malignant phenotype of the suitably transfected cells was assessed by standard in vitro functional assays and the establishment of in vivo xenografts. The expression levels of the specific markers were analyzed with RT-qPCR and western blotting. The subcellular localization of P53 was determined by analyzing the nuclear and cytoplasmic fractions. RIP, Co-IP, and immunohistochemistry were performed as per standard protocols. Results. SNORD15B was overexpressed in the endometrial cancer tissues and correlated to a poor prognosis. Ectopic expression of SNORD15B in Ishikawa cells inhibited apoptosis, increased the proliferation, invasion, and migration in vitro, and enhanced their tumorigenicity in vivo. SNORD15B overexpression also upregulated TRIM25 and accelerated P53 accumulation in the cytoplasm of the endometrial cancer cells. Conclusion. SNORD15B functions as an oncogene in endometrial cancer by targeting the TRIM25/P53 complex and blocking the nuclear translocation of P53.

Gene fusions are thought to be driver mutations in multiple cancers and are an important factor for poor patient prognosis. Most of them appear in specific cancers, thus satisfactory strategies can be developed for the precise treatment of these types of cancer. Currently, there are few targeted drugs to treat gynecologic tumors, and patients with gynecologic cancer often have a poor prognosis because of tumor progression or recurrence. With the application of massively parallel sequencing, a large number of fusion genes have been discovered in gynecologic tumors, and some fusions have been confirmed to be involved in the biological process of tumor progression. To this end, the present article reviews the current research status of all confirmed fusion genes in gynecologic tumors, including their rearrangement mechanism and frequency in ovarian cancer, endometrial cancer, endometrial stromal sarcoma, and other types of uterine tumors. We also describe the mechanisms by which fusion genes are generated and their oncogenic mechanism. Finally, we discuss the prospect of fusion genes as therapeutic targets in gynecologic tumors.