Risk SNP-mediated LINC01614 upregulation drives head and neck squamous cell carcinoma progression via PI3K/AKT signaling pathway

LncRNAs exhibit subtype-specific expression, survival associations, and cancer-promoting effects in breast cancer

Long non-coding RNAs (lncRNAs) play important roles in cancer progression, influencing processes such as invasion, metastasis, and drug resistance. Their reported cell type-dependent expression patterns suggest the potential for specialized functions in specific contexts. In breast cancer, lncRNA expression has been associated with different subtypes, highlighting their relevance in disease heterogeneity. However, our understanding of lncRNA function within breast cancer subtypes remains limited, warranting further investigation. We conducted a comprehensive analysis using the TANRIC dataset derived from the TCGA-BRCA cohort, profiling the expression, patient survival associations and immune cell type correlations of 12,727 lncRNAs across subtypes. Our findings revealed subtype-specific associations of lncRNAs with patient survival, tumor infiltrating lymphocytes and other immune cells. Targeting of lncRNAs exhibiting subtype-specific survival associations and expression in a panel of breast cancer cells demonstrated a selective reduction in cell proliferation within their associated subtype, supporting subtype-specific functions of certain lncRNAs. Characterization of HER2 + -specific lncRNA LINC01269 and TNBC-specific lncRNA AL078604.2 showed nuclear localization and altered expression of hundreds of genes enriched in cancer-promoting processes, including apoptosis, cell proliferation and immune cell regulation. This work emphasizes the importance of considering the heterogeneity of breast cancer subtypes and the need for subtype-specific analyses to fully uncover the relevance and potential impact of lncRNAs. Collectively, these findings demonstrate the contribution of lncRNAs to the distinct molecular, prognostic, and cellular composition of breast cancer subtypes.

UPR-Induced miR-616 Inhibits Human Breast Cancer Cell Growth and Migration by Targeting c-MYC

C/EBP homologous protein (CHOP), also known as growth arrest and DNA damage-inducible protein 153 (GADD153), belongs to the CCAAT/enhancer-binding protein (C/EBP) family. CHOP expression is induced by unfolded protein response (UPR), and sustained CHOP activation acts as a pivotal trigger for ER stress-induced apoptosis. MicroRNA-616 is located within an intron of the CHOP gene. However, the regulation of miR-616 expression during UPR and its function in breast cancer is not clearly understood. Here we show that the expression of miR-616 and CHOP (host gene of miR-616) is downregulated in human breast cancer. Both miR-5p/-3p arms of miR-616 are expressed with levels of the 5p arm higher than the 3p arm. During conditions of ER stress, the expression of miR-616-5p and miR-616-3p arms was concordantly increased primarily through the PERK pathway. Our results show that ectopic expression of miR-616 significantly suppressed cell proliferation and colony formation, whereas knockout of miR-616 increased it. We found that miR-616 represses c-MYC expression via binding sites located in its protein coding region. Furthermore, we show that miR-616 exerted growth inhibitory effects on cells by suppressing c-MYC expression. Our results establish a new role for the CHOP locus by providing evidence that miR-616 can inhibit cell proliferation by targeting c-MYC. In summary, our results suggest a dual function for the CHOP locus, where CHOP protein and miR-616 can cooperate to inhibit cancer progression.

Long non-coding RNA FAM239A promotes tumor cell proliferation and migration by regulating tyrosine phosphatase Src homology 2 domain-containing phosphatase 2 in head and neck squamous cell carcinoma

OBJECTIVE

Head and neck squamous cell carcinoma (HNSCC), is one of the malignant tumors with high recurrence and metastasis. The family with sequence similarity (FAM) of non-coding RNAs promoted tumorigenesis and metastasis. But so far, long non-coding RNA (lncRNA) FAM239A's function in HNSCC regulation remains unclear. This study aimed to explore the lncRNA FAM239A function and regulation mechanism in HNSCC cell proliferation and migration.

DESIGN

The expression level of lncRNA FAM239A and tyrosine phosphatase Src homology 2 domain-containing phosphatase 2 (SHP2) in HNSCC tumor tissue was tested by quantitative polymerase chain reaction. The cell proliferation and migration were tested by cell counting kit 8, kinetic live cell assay, and wound healing assay. The differential expression of SHP2 and immune infiltration in HNSCC were analyzed in the tumor immune estimation response and human protein atlas databases. And the survival analysis of SHP2 in HNSCC was analyzed in the gene expression profiling interactive analysis 2 databases. The SHP2 expression was tested by western blotting when lncRNA FAM239A overexpression and knockdown.

RESULTS

LncRNA FAM239A and SHP2 were ectopically expressed in HNSCC tumor tissue. Cell proliferation and wound healing assays showed that lncRNA FAM239A promoted tumor cell proliferation and migration. SHP2 was overexpressed in HNSCC tumor tissue by database analyses, and the higher SHP2 expression caused poorer overall survival and disease-free survival in HNSCC patients. SHP2 expression was positively regulated by lncRNA FAM239A.

CONCLUSIONS

LncRNA FAM239A promoted HNSCC cell proliferation and migration through upregulating SHP2 expression, which potentially provided new regulators for HNSCC.

SNP-Target Genes Interaction Perturbing the Cancer Risk in the Post-GWAS

Cancer ranks as the second leading cause of death worldwide, and, being a genetic disease, it is highly heritable. Over the past few decades, genome-wide association studies (GWAS) have identified many risk-associated loci harboring hundreds of single nucleotide polymorphisms (SNPs). Some of these cancer-associated SNPs have been revealed as causal, and the functional characterization of the mechanisms underlying the cancer risk association has been illuminated in some instances. In this review, based on the different positions of SNPs and their modes of action, we discuss the mechanisms underlying how SNPs regulate the expression of target genes to consequently affect tumorigenesis and the development of cancer.