miR-330-5p Suppress Cell Growth and Invasion via Disrupting HSF4-mediated MACC1/STAT3 Pathway in Colorectal Cancer.

BACKGROUND: Recently, miRNAs are demonstrated to restrain mRNA translation through novel pattern with bind complementary sites in the coding sequence (CDS). Heat Shock Transcription Factor 4 (HSF4) has been newly described as a tumor-associated transcription factor. Therefore, the present study intends to explore miRNAs that bind CDS region of HSF4, and identify the function of their interactions in the malignant biological behavior of colorectal cancer (CRC). METHODS: Prognostic value of HSF4 and correlation between HSF4 and MACC1 expression were estimated via bioinformatics with the Cancer Genome Atlas (TCGA) data. HSF4 and downstream MACC1/STAT3 signaling cascade was characterized by immunoblotting. To characterize the effects of miR-330-5p and HSF4 on the malignant phenotype of CRC cells by functional experiments. The binding activity of miR-330-5p to coding sequence (CDS) of HSF4 was identified using DIANA-microT-CDS algorithm and dual-luciferase reporter assay. RESULTS: HSF4 was aberrantly overexpressed and associated with poor outcomes of CRC patients. Overexpression of HSF4 was correlated with Tumor Node Metastasis stage, and positively regulated malignant behaviors such as growth, migration, invasion of CRC cells. Moreover, miR-330-5p suppressed CRC cell growth, colony formation, migration and invasive. Interestingly, miR-330-5p recognized complementary sites within the HSF4 CDS region to reduce HSF4 expression. In rescue experiments, restoration of HSF4 expression functionally alleviated miR-330-5p-induced inhibition of cell growth, colon formation, invasion, and wound healing of CRC cells. HSF4 was associated positively with the well-known oncogenic factor MACC1 in TCGA cohort CRC samples, and knockdown of HSF4 resulted in downregulation of MACC1. In mechanism, MACC1 was suppressed upon miR-330-5p-induced downregulation of HSF4, leading to inactivation of phosphorylation of downstream STAT3. CONCLUSION: miR-330-5p suppresses tumors by directly inhibiting HSF4 to negatively modify activity of MACC1/STAT3 pathway.

HSF4 promotes tumor progression of colorectal cancer by transactivating c-MET.

Heat shock factors (HSFs) are a family of transcription factors, composed of HSF1, HSF2, and HSF4, to regulate cell stress reaction for maintaining cellular homeostasis in response to adverse stimuli. Recent studies have disclosed the roles of HSF1 and HSF2 in modulating tumor development, including colorectal cancer (CRC). However, HSF4, which is closely associated with pathology of congenital cataracts, remains less studied in tumors. In this study, we aimed to describe the regulatory effects of HSF4 and underlying molecular mechanism in CRC progression. By bioinformatic analysis of TCGA database and TMA-IHC assay, we identified that the expression of HSF4 was significantly upregulated in CRCs compared with normal colonic tissues and was a prognostic factor of poor outcomes of CRC patients. Function assays, including CCK-8, colony formation, transwell assays, and xenografted mouse model, were employed to verify that HSF4 promoted cell growth, colony formation, invasion of CRC cells in vitro, and tumor growth in vivo as a potential oncogenic factor. Mechanistically, results of Chromatin immunoprecipitation (ChIP) and immunoblotting assays revealed that HSF4 associated directly to MET promoter to enhance expression of c-MET, a well-known oncogene in multiple cancers, thus fueling the activity of downstream ERK1/2 and AKT signaling pathways. In further rescue experiments, restoration of c-MET expression abolished inhibitory cell growth and invasion induced by downregulated HSF4 expression. To sum up, our findings describe a crucial role of HSF4 in CRC progression by enhancing activity of c-MET and downstream ERK1/2 and AKT signaling pathways, and highlight HSF4 as a potential therapeutic target for anti-CRC treatment.

Association between heat shock factor protein 4 methylation and colorectal cancer risk and potential molecular mechanisms: A bioinformatics study.

BACKGROUND: We previously demonstrated that heat shock factor protein 4 (HSF4) facilitates colorectal cancer (CRC) progression. DNA methylation, a major modifier of gene expression and stability, is involved in CRC development and outcome. AIM: To investigate the correlation between HSF4 methylation and CRC risk, and to uncover the underlying molecular mechanisms. METHODS: Differences in ß values of HSF4 methylation loci in multiple malignancies and their correlation with HSF4 mRNA expression were analyzed based on Shiny Methylation Analysis Resource Tool. HSF4 methylation-related genes were identified by LinkedOmics in CRC, and Gene Ontology and Kyoto Encyclopedia of Genes and Genomes enrichment analyses were performed. Protein-protein interaction network of HSF4 methylation-related genes was constructed by String database and MCODE algorithm. RESULTS: A total of 19 CpG methylation loci were identified in HSF4, and their ß values were significantly increased in CRC tissues and exhibited a positive correlation with HSF4 mRNA expression. Unfortunately, the prognostic and diagnostic performance of these CpG loci in CRC patients was mediocre. In CRC, there were 1694 HSF4 methylation-related genes; 1468 of which displayed positive and 226 negative associations, and they were involved in regulating phenotypes such as immune, inflammatory, and metabolic reprogramming. EGFR, RELA, STAT3, FCGR3A, POLR2K, and AXIN1 are hub genes among the HSF4 methylation-related genes. CONCLUSION: HSF4 is highly methylated in CRC, but there is no significant correlation between it and the prognosis and diagnosis of CRC. HSF4 methylation may serve as one of the ways in which HSF4 mediates the CRC process.

Forkhead Box Q1 Is Critical to Angiogenesis and Macrophage Recruitment of Colorectal Cancer.

Angiogenesis and the tumor microenvironment (TME) play important roles in tumorigenesis. Forkhead box Q1 (FOXQ1) is a well-established oncogene in multiple tumors, including colorectal cancer (CRC); however, whether FOXQ1 contributes to angiogenesis and TME modification in CRC remains largely uncharacterized. Here, we demonstrate an essential role of FOXQ1-induced angiogenesis and macrophage recruitment in CRC that is related to its ability to promote the migration of endothelial cells and macrophages through activation of the EGF/PDGF pathway and the Twist1/CCL2 axis. We also provide evidence showing that the clinical significance between FOXQ1, Twist1, CCL2, and macrophage infiltration is associated with reduced 8-year survival in CRC patients. Our findings suggest FOXQ1 plays critical roles in the malignancy and progression of CRC, Therefore, FOXQ1 may serve as a therapeutic target for inhibiting angiogenesis and reducing macrophage recruitment in CRC.