Silencing of long non-coding RNAs MIR22HG, LNCTAM34A, and TP53TG1 triggers cell survival/proliferation and inhibits apoptosis in women's breast cancer

This study investigated the functional and translational role of long non-coding RNAs (lncRNAs), specifically MIR22HG, LNCTAM34A, and TP53TG1, in breast cancer (BC). The expression of the lncRNAs was measured using RT-qPCR. Knockdown experiments using siRNA were conducted in breast cancer cell lines (MDA-MB-231, MDA-MB-453, and MCF-7) to assess the functional impact of silencing these lncRNAs. Cell proliferation, colony formation, invasion, migration, and apoptosis assays were performed to evaluate phenotypic changes. The expression of MIR22HG, LNCTAM34A, and TP53TG1 was significantly decreased in tumor tissues compared to NATs ( p < 0.05). Lower expression of these lncRNAs correlated with advanced TNM stage and grade groups ( p < 0.05). MIR22HG was overexpressed in the BC cell lines MDA-MB-231 and MCF-7, while LNCTAM34A and TP53TG1 were upregulated in MDA-MB-453 and MCF-7 BC cell lines. Silencing these lncRNAs led to a significant increase in cell proliferation, colony formation, invasion, and migration ( p < 0.001). Additionally, apoptosis was significantly decreased in cells with silenced lncRNAs ( p < 0.05). Knockdown of MIR22HG, LNCTAM34A, and TP53TG1 in BC cells resulted in increased cell proliferation and colony formation. Silencing of these lncRNAs significantly increased cell migration and invasion. The silencing of MIR22HG, LNCTAM34A, and TP53TG1 decreased apoptosis in BC cells. Study demonstrates that MIR22HG, LNCTAM34A, and TP53TG1 function as tumor suppressors in breast cancer. Downregulation of these lncRNAs promotes tumor progression by enhancing cell proliferation, invasion, and migration, while inhibiting apoptosis.