Upregulation of lncRNA GATA6-AS suppresses the migration and invasion of cervical squamous cell carcinoma by downregulating MTK-1

MAP3K4 kinase action and dual role in cancer

It is commonly known that the MAPK pathway is involved in translating environmental inputs, regulating downstream reactions, and maintaining the intrinsic dynamic balance. Numerous essential elements and regulatory processes are included in this pathway, which are essential to its functionality. Among these, MAP3K4, a member of the serine/threonine kinases family, plays vital roles throughout the organism's life cycle, including the regulation of apoptosis and autophagy. Moreover, MAP3K4 can interact with key partners like GADD45, which affects organism's growth and development. Notably, MAP3K4 functions as both a tumor promotor and suppressor, being activated by a variety of factors and triggering diverse downstream pathways that differently influence cancer progression. The aim of this study is to provide a brief overview of physiological functions of MAP3K4 and shed light on its contradictory roles in tumorigenesis.

Oncogenic role of ALX3 in cervical cancer cells through KDM2B-mediated histone demethylation of CDC25A

Background

Cell division cycle 25A (CDC25A) is a well-recognized regulator of cell cycle progression and is involved in cancer development. This work focused on the function of CDC25A in cervical cancer cell growth and the molecules involved.

Methods

A GEO dataset GSE63514 comprising data of cervical squamous cell carcinoma (CSCC) tissues was used to screen the aberrantly expressed genes in cervical cancer. The CDC25A expression in cancer and normal tissues was predicted in the GEPIA database and that in CSCC and normal cells was determined by RT-qPCR and western blot assays. Downregulation of CDC25A was introduced in CSCC cells to explore its function in cell growth and the cell cycle progression. The potential regulators of CDC25A activity and the possible involved signaling were explored.

Results

CDC25A was predicted to be overexpressed in CSCC, and high expression of CDC25A was observed in CSCC cells. Downregulation of CDC25A in ME180 and C33A cells reduced cell proliferation and blocked cell cycle progression, and it increased cell apoptosis. ALX3 was a positive regulator of CDC25A through transcription promotion. It recruited a histone demethylase, lysine demethylase 2B (KDM2B), to the CDC25A promoter, which enhanced CDC25A expression through demethylation of H3k4me3. Overexpression of ALX3 in cells blocked the inhibitory effects of CDC25A silencing. CDC25A was found as a positive regulator of the PI3K/Akt signaling pathway.

Conclusion

This study suggested that the ALX3 increased CDC25A expression through KDM2B-mediated demethylation of H3K4me3, which induced proliferation and cell cycle progression of cervical cancer cells.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-021-08552-7.

Knockdown of TPT1-AS1 inhibits cell proliferation, cell cycle G1/S transition, and epithelial-mesenchymal transition in gastric cancer

Long non-coding RNAs are considered to be critical regulators of tumor progression. Tumor protein translationally controlled 1 antisense RNA 1 (TPT1-AS1) was shown to have an oncogenic role in cervical and ovarian cancer. The clinical significance and biological function of TPT1-AS1 in gastric cancer (GC) are not clear. In this study, we analyzed the expression of TPT1-AS1 in GC tissues and cell lines and performed functional and mechanistic analysis of TPT1-AS1 effects on GC cell proliferation, migration, and invasion. TPT1-AS1 expression was determined in 76 pairs of GC tissues vs. matched adjacent normal tissues and in four GC cell lines (SGC-7901, AGS, BGC-823, and MGC-803) vs. GES-1 cell line by quantitative reverse transcription PCR. SGC-7901 and MGC-803 cells were transfected with small interfering RNA or scrambled negative control, and cell proliferation, colony formation, migration, invasion and cell cycle assays were performed. The expression of proteins involved in cell cycle progression and epithelial-mesenchymal transition was analyzed by Western blot. TPT1-AS1 expression was significantly higher in GC tissues and cell lines compared to controls. The overexpression of TPT1-AS1 was significantly correlated with TNM stage and lymph node metastasis, and it was associated with worse prognosis of GC patients according to the Kaplan-Meier survival analysis and Cox proportional hazard regression analysis. The knockdown of TPT1-AS1 significantly inhibited proliferation, cell cycle G1/S transition, migration, and invasion of SGC-7901 and MGC-803 cells. Moreover, TPT1-AS1 knockdown downregulated the expression of cyclin-dependent kinase (CDK) 4, cyclin D1, and vimentin and upregulated the expression of p21 and E-cadherin. Our findings suggest that TPT1-AS1 may be a promising therapeutic target in GC.

Beyond MicroRNAs: Emerging Role of Other Non-Coding RNAs in HPV-Driven Cancers

Persistent infection with high-risk Human Papilloma Virus (HPV) leads to the development of several tumors, including cervical, oropharyngeal, and anogenital squamous cell carcinoma. In the last years, the use of high-throughput sequencing technologies has revealed a number of non-coding RNA (ncRNAs), distinct from micro RNAs (miRNAs), that are deregulated in HPV-driven cancers, thus suggesting that HPV infection may affect their expression. However, since the knowledge of ncRNAs is still limited, a better understanding of ncRNAs biology, biogenesis, and function may be challenging for improving the diagnosis of HPV infection or progression, and for monitoring the response to therapy of patients affected by HPV-driven tumors. In addition, to establish a ncRNAs expression profile may be instrumental for developing more effective therapeutic strategies for the treatment of HPV-associated lesions and cancers. Therefore, this review will address novel classes of ncRNAs that have recently started to draw increasing attention in HPV-driven tumors, with a particular focus on ncRNAs that have been identified as a direct target of HPV oncoproteins.

The Role of Long Noncoding RNAs in Human Papillomavirus-associated Pathogenesis

Infections with high-risk human papillomaviruses cause ~5% of all human cancers. E6 and E7 are the only viral genes that are consistently expressed in cancers, and they are necessary for tumor initiation, progression, and maintenance. E6 and E7 encode small proteins that lack intrinsic enzymatic activities and they function by binding to cellular regulatory molecules, thereby subverting normal cellular homeostasis. Much effort has focused on identifying protein targets of the E6 and E7 proteins, but it has been estimated that ~98% of the human transcriptome does not encode proteins. There is a growing interest in studying noncoding RNAs as biochemical targets and biological mediators of human papillomavirus (HPV) E6/E7 oncogenic activities. This review focuses on HPV E6/E7 targeting cellular long noncoding RNAs, a class of biologically versatile molecules that regulate almost every known biological process and how this may contribute to viral oncogenesis.