Topoisomerase II alpha promotes gallbladder cancer proliferation and metastasis through activating phosphatidylinositol 3-kinase/protein kinase B/mammalian target of rapamycin signaling pathway

POU2F1 inhibits miR-29b1/a cluster-mediated suppression of PIK3R1 and PIK3R3 expression to regulate gastric cancer cell invasion and migration

BACKGROUND

The transcription factor POU2F1 regulates the expression levels of microRNAs in neoplasia. However, the miR-29b1/a cluster modulated by POU2F1 in gastric cancer (GC) remains unknown.

METHODS

Gene expression in GC cells was evaluated using reverse-transcription polymerase chain reaction (PCR), western blotting, immunohistochemistry, and RNA in situ hybridization. Co-immunoprecipitation was performed to evaluate protein interactions. Transwell migration and invasion assays were performed to investigate the biological behavior of GC cells. MiR-29b1/a cluster promoter analysis and luciferase activity assay for the 3'-UTR study were performed in GC cells. In vivo tumor metastasis was evaluated in nude mice.

RESULTS

POU2F1 is overexpressed in GC cell lines and binds to the miR-29b1/a cluster promoter. POU2F1 is upregulated, whereas mature miR-29b-3p and miR-29a-3p are downregulated in GC tissues. POU2F1 promotes GC metastasis by inhibiting miR-29b-3p or miR-29a-3p expression in vitro and in vivo . Furthermore, PIK3R1 and/or PIK3R3 are direct targets of miR-29b-3p and/or miR-29a-3p , and the ectopic expression of PIK3R1 or PIK3R3 reverses the suppressive effect of mature miR-29b-3p and/or miR-29a-3p on GC cell metastasis and invasion. Additionally, the interaction of PIK3R1 with PIK3R3 promotes migration and invasion, and miR-29b-3p , miR-29a-3p , PIK3R1 , and PIK3R3 regulate migration and invasion via the phosphatidylinositol 3-kinase/protein kinase B/mammalian target of rapamycin (PI3K/Akt/mTOR) pathway in GC cells. In addition, POU2F1 , PIK3R1 , and PIK3R3 expression levels negatively correlated with miR-29b-3p and miR-29a-3p expression levels in GC tissue samples.

CONCLUSIONS

The POU2F1 - miR-29b-3p / miR-29a-3p-PIK3R1 / PIK3R1 signaling axis regulates tumor progression and may be a promising therapeutic target for GC.

TOP2A modulates signaling via the AKT/mTOR pathway to promote ovarian cancer cell proliferation

Ovarian cancer (OC) is a form of gynecological malignancy that is associated with worse patient outcomes than any other cancer of the female reproductive tract. Topoisomerase II α (TOP2A) is commonly regarded as an oncogene that is associated with malignant disease progression in a variety of cancers, its mechanistic functions in OC have yet to be firmly established. We explored the role of TOP2A in OC through online databases, clinical samples, in vitro and in vivo experiments. And initial analyses of public databases revealed high OC-related TOP2A expression in patient samples that was related to poorer prognosis. This was confirmed by clinical samples in which TOP2A expression was elevated in OC relative to healthy tissue. Kaplan-Meier analyses further suggested that higher TOP2A expression levels were correlated with worse prognosis in OC patients. In vitro, TOP2A knockdown resulted in the inhibition of OC cell proliferation, with cells entering G1 phase arrest and undergoing consequent apoptotic death. In rescue assays, TOP2A was confirmed to regulate cell proliferation and cell cycle through AKT/mTOR pathway activity. Mouse model experiments further affirmed the key role that TOP2A plays as a driver of OC cell proliferation. These data provide strong evidence supporting TOP2A as an oncogenic mediator and prognostic biomarker related to OC progression and poor outcomes. At the mechanistic level, TOP2A can control tumor cell growth via AKT/mTOR pathway modulation. These preliminary results provide a foundation for future research seeking to explore the utility of TOP2A inhibitor-based combination treatment regimens in platinum-resistant recurrent OC patients.

miR-30c-2-3p suppresses the proliferation of human renal cell carcinoma cells by targeting TOP2A

Background

The ambiguity of renal cell carcinoma (RCC) symptoms hinders early diagnosis, thereby contributing to high mortality rates. By attaching to the 3'-untranslated region (UTR) of the target gene, microRNAs (miRNAs) exert significant control over the expression of genes.

Objectives

To investigate the influence of miR-30c-2-3p and DNA topoisomerase II alpha (TOP2A) on RCC growth and the mechanisms underlying the regulation of its expression.

Methods

The expression of miRNA-30c-2-3p and TOP2A in RCC cells was examined using quantitative real-time polymerase chain reaction (qRT-PCR). MiR-30c-2-3p mimics, its inhibitors, and controls, as well as TOP2A short hairpin RNA (shRNA) and controls, were used to transfect the human RCC cell lines 786-O, Caki-1, and ACHN. Additionally, the roles of miRNA-30c-2-3p and TOP2A in the growth of RCC were evaluated using the cell counting kit (CCK)-8 test, colony formation assay, apoptosis analysis, and Western blotting. Meanwhile, binding of miRNA-30c-2-3p and TOP2A was verified using dual-luciferase reporter assays and Western blotting.

Results

miR-30c-2-p is underexpressed in RCC cells. Overexpression of miR-30c-2-p promotes apoptosis and inhibits proliferation of ACHN, Caki-1, and 786-O cells. miR-30c-2-3p targets TOP2A, which is elevated in RCC tissues and cells, whereas TOP2A silencing inhibits the proliferation ability of RCC cells. The miRNA-30c-2-3p inhibitor compromises TOP2A shRNA-induced apoptosis of RCC. RCC cells cotransfected with miRNA-30c-2-3p inhibitors and TOP2A shRNAs have a higher proliferation rate than those transfected with only TOP2A shRNAs.

Conclusions

Collectively, our results verify that miRNA-30c-2-3p has a tumor suppressor property. miRNA-30c-2-3p inhibits the proliferation of RCC through regulation of TOP2A. The data provide a viable therapeutic target for RCC.

A Comprehensive narrative review of transcriptomics and epigenomics of gallbladder cancer

ABSTRACTS

Gallbladder cancer (GBC) is one of the quiet prevalent and aggressive biliary tract malignant neoplasms distinguished by significant cellular heterogeneity, metastatic activity, and a poor prognosis, with varied frequency worldwide. Most cases are detected incidentally while routine screening imaging or pathological investigation of cholecystectomy tissues and usually present with advanced disease. The surgical resection is usually done in the initial clinical stage having limited spread. Despite the surgical therapy, the death rate is significant. Furthermore, the molecular mechanisms affecting the clinical course of inflammatory gallbladder to carcinogenesis remain poorly understood. There is an impending need for developing diagnostic biomarkers and targeted approaches for GBC. The newer molecular platform, such as next-generation sequencing (NGS), such as RNA-sequencing (RNAseq), single-cell sequencing, and microarray technology, has revolutionized the field of genomics, opened a new perspective in defining genetic and epigenetic characteristics identifying molecules as possible therapeutic targets. Therefore, in this review, we would analyze transcriptomic and epigenomics profiles of GBC using already published high-throughput sequencing-based studies published between 2010 and 2023. The review would also analyze the possible impact of the technological advancement on the patient management strategy and overall survival. This may also help identify target genes and pathways linked to GBC, which may help establish molecular biomarkers, for early GBC diagnosis, personalized therapy, and management.

Identification of Human Cell Cycle Phase Markers Based on Single-Cell RNA-Seq Data by Using Machine Learning Methods

The cell cycle is composed of a series of ordered, highly regulated processes through which a cell grows and duplicates its genome and eventually divides into two daughter cells. According to the complex changes in cell structure and biosynthesis, the cell cycle is divided into four phases: gap 1 (G1), DNA synthesis (S), gap 2 (G2), and mitosis (M). Determining which cell cycle phases a cell is in is critical to the research of cancer development and pharmacy for targeting cell cycle. However, current detection methods have the following problems: (1) they are complicated and time consuming to perform, and (2) they cannot detect the cell cycle on a large scale. Rapid developments in single-cell technology have made dissecting cells on a large scale possible with unprecedented resolution. In the present research, we construct efficient classifiers and identify essential gene biomarkers based on single-cell RNA sequencing data through Boruta and three feature ranking algorithms (e.g., mRMR, MCFS, and SHAP by LightGBM) by utilizing four advanced classification algorithms. Meanwhile, we mine a series of classification rules that can distinguish different cell cycle phases. Collectively, we have provided a novel method for determining the cell cycle and identified new potential cell cycle-related genes, thereby contributing to the understanding of the processes that regulate the cell cycle.

Identification of the Potential Prognosis Biomarkers in Hepatocellular Carcinoma: An Analysis Based on WGCNA and PPI

Aim

This study was done to determine biomarkers for the prognostic prediction of hepatocellular carcinoma (HCC).

Materials and Methods

In the Gene Expression Omnibus, the gene expression profiles of HCC were downloaded. Biomarkers were identified by weighted gene co-expression network analysis and protein–protein interaction network analysis.

Results

There were 24 modules, which were characterized by the high correlation with HCC. Meanwhile, through enrichment analysis, differentially expressed genes were largely participated in the ubiquitination and autophagy processes. Moreover, PRC1, TOP2A and CKAP2L may be the hub genes involved in HCC tumorigenesis, and their biomarker roles were further demonstrated via Gene Expression Profiling Interactive Analysis (GEPIA) and Oncomine databases. In addition, the levels of PRC1, TOP2A and CKAP2L were obviously up-regulated in the sera of HCC patients.

Conclusion

PRC1, TOP2A and CKAP2L may serve as biomarkers for the prognostic prediction of HCC patients.

Molecular mechanisms involved in DNA repair in human cancers: An overview of PI3k/Akt signaling and PIKKs crosstalk

The cellular genome is frequently subjected to abundant endogenous and exogenous factors that induce DNA damage. Most of the Phosphatidylinositol 3-kinase-related kinases (PIKKs) family members are activated in response to DNA damage and are the most important DNA damage response (DDR) proteins. The DDR system protects the cells against the wrecking effects of these genotoxicants and repairs the DNA damage caused by them. If the DNA damage is severe, such as when DNA is the goal of chemo-radiotherapy, the DDR drives cells toward cell cycle arrest and apoptosis. Some intracellular pathways, such as PI3K/Akt, which is overactivated in most cancers, could stimulate the DDR process and failure of chemo-radiotherapy with the increasing repair of damaged DNA. This signaling pathway induces DNA repair through the regulation of proteins that are involved in DDR like BRCA1, HMGB1, and P53. In this review, we will focus on the crosstalk of the PI3K/Akt and PIKKs involved in DDR and then discuss current achievements in the sensitization of cancer cells to chemo-radiotherapy by PI3K/Akt inhibitors.