Long noncoding RNA RP11-241J12.3 targeting pyruvate carboxylase promotes hepatocellular carcinoma aggressiveness by disrupting pyruvate metabolism and the DNA mismatch repair system

Glycolysis-related gene dihydrolipoamide acetyltransferase promotes poor prognosis in hepatocellular carcinoma through the Wnt/β-catenin and PI3K/Akt signaling pathways

Background

Recent research suggests that dihydrolipoamide acetyltransferase (DLAT), which is a copper-induced cell death-related gene, is involved in multiple biological events in tumors. This study sought to investigate the relationship between DLAT and hepatocellular carcinoma (HCC).

Methods

In the Cancer Genome Atlas (TCGA) database, we first identified the differentially expressed gene (i.e., DLAT), then confirmed DLAT expression, and found a link between it and the prognosis of HCC patients. An internal validation nomogram was built based on a multivariate Cox regression analysis. Data from the Tumor Immune Estimation Resource (TIMER) database was used to examine the association between DLT and immunological cells. A gene set enrichment analysis (GSEA) was conducted to investigate the probable mechanism of action. Finally, in vitro cytological research was conducted to further examin the involvement of DLAT in HCC-related unfavorable biological events.

Results

The database screenings showed that DLAT was a differentially expressed molecule; that is, DLAT was more highly expressed in the cancer tissues than normal tissues. TCGA results and Kaplan-Meier-plotter data sets showed that HCC patients with reduced DLAT expression had greater disease-specific survival (DSS), overall survival (OS), and progression-free interval (PFI). The prediction model had a concordance index of 0.659 (0.614-0.704), which indicates high accuracy. According to the TIMER database, tumor cells in the HCC microenvironment may be able to bypass the immune system due to the expression of DLAT. The in vitro cytological tests showed that DLAT knockdown significantly decreased the proliferation and invasion of the HCC cells. It also inhibited the activity of the phosphatidylinositol-4,5-bisphosphate 3-kinase (PI3K)/protein kinase B (Akt) and Wnt/β-catenin signaling pathways.

Conclusions

Decreased DLAT expression significantly prolongs the OS, PFI, and DSS of HCC patients. DLAT may be employed as a new predictive biomarker for HCC, and may be linked to the immune system in HCC patients. The tumor microenvironment (TME) may have a significant effect on the ability of tumor cells to evade the immune system. The PI3K/Akt and Wnt/β-catenin signaling pathways may affect the prognosis of HCC by interfering with DLAT. Given these findings, HCC may be an ideal target for the development of anti-cancer therapies.

The role and mechanism of noncoding RNAs in regulation of metabolic reprogramming in hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is the most common type of primary liver cancer. Metabolic reprogramming is considered to be an important hallmark of cancer. Emerging studies have demonstrated that noncoding RNAs (ncRNAs) are closely associated with metabolic reprogramming of HCC. NcRNAs can directly regulate the expressions or functions of metabolic enzymes or indirectly regulate the metabolism of HCC cells through some vital signaling pathways. Until now, the mechanisms of HCC development and progression remain largely unclear, and understanding the regulatory mechanism of ncRNAs on metabolic reprogramming of HCC may provide an important basis for breakthrough progress in the treatment of HCC. In this review, we summarize the ncRNAs involved in regulating metabolic reprogramming of HCC. Specifically, the regulatory roles of ncRNAs in glucose, lipid and amino acid metabolism are elaborated. In addition, we discuss the molecular mechanism of ncRNAs in regulation of metabolic reprogramming and possible therapeutic strategies that target the metabolism of cancer cells by modulating the expressions of specific ncRNAs.