CDK5 destabilizes PD-L1 via chaperon-mediated autophagy to control cancer immune surveillance in hepatocellular carcinoma

Targeting cell death mechanisms: the potential of autophagy and ferroptosis in hepatocellular carcinoma therapy

Ferroptosis is a type of cell death that plays a remarkable role in the growth and advancement of malignancies including hepatocellular carcinoma (HCC). Non-coding RNAs (ncRNAs) have a considerable impact on HCC by functioning as either oncogenes or suppressors. Recent research has demonstrated that non-coding RNAs (ncRNAs) have the ability to control ferroptosis in HCC cells, hence impacting the advancement of tumors and the resistance of these cells to drugs. Autophagy is a mechanism that is conserved throughout evolution and plays a role in maintaining balance in the body under normal settings. Nevertheless, the occurrence of dysregulation of autophagy is evident in the progression of various human disorders, specifically cancer. Autophagy plays dual roles in cancer, potentially influencing both cell survival and cell death. HCC is a prevalent kind of liver cancer, and genetic mutations and changes in molecular pathways might worsen its advancement. The role of autophagy in HCC is a subject of debate, as it has the capacity to both repress and promote tumor growth. Autophagy activation can impact apoptosis, control proliferation and glucose metabolism, and facilitate tumor spread through EMT. Inhibiting autophagy can hinder the growth and spread of HCC and enhance the ability of tumor cells to respond to treatment. Autophagy in HCC is regulated by several signaling pathways, such as STAT3, Wnt, miRNAs, lncRNAs, and circRNAs. Utilizing anticancer drugs to target autophagy may have advantageous implications for the efficacy of cancer treatment.

LncRNA PRBC induces autophagy to promote breast cancer progression through modulating PABPC1-mediated mRNA stabilization

Breast cancer is one of the major malignant tumors among women worldwide. Long noncoding RNAs (lncRNAs) have been documented as significant modulators in the development and progression of various cancers; however, the contribution of lncRNAs to breast cancer remains largely unknown. In this study, we found a novel lncRNA (NONHSAT137675) whose expression was significantly increased in the breast cancer tissues. We named the novel lncRNA as lncRNA PRBC (PABPC1-related lncRNA in breast cancer) and identified it as a key lncRNA associated with breast cancer progression and prognosis. Functional analysis displayed that lncRNA PRBC could promote autophagy and progression of breast cancer. Mechanistically, we verified that lncRNA PRBC physically interacted with PABPC1 through RIP assay, and PABPC1 overexpression could reverse the inhibiting effect of lncRNA PRBC knockdown on the malignant behaviors in breast cancer cells. Knockdown of lncRNA PRBC interfered the translocation of PABPC1 from nucleus to cytoplasm as indicated by western blot and IF assays. Significantly, the cytoplasmic location of PABPC1 was required for the interaction between PABPC1 and AGO2, which could be enhanced by lncRNA PRBC overexpression, leading to strengthened recruitment of mRNA to RNA-induced silencing complex (RISC) and thus reinforcing the inhibition efficiency of miRNAs. In general, lncRNA PRBC played a critical role in malignant progression of breast cancer by inducing the cytoplasmic translocation of PABPC1 to further regulate the function of downstream miRNAs. This study provides novel insight on the molecular mechanism of breast cancer progression, and lncRNA PRBC might be a promising therapeutic target and prognostic predictor for breast cancer.