miR-154 Influences HNSCC Development and Progression through Regulation of the Epithelial-to-Mesenchymal Transition Process and Could Be Used as a Potential Biomarker.

MicroRNAs and their role in cancer have been extensively studied for the past decade. Here, we analyzed the biological role and diagnostic potential of miR-154-5p and miR-154-3p in head and neck squamous cell carcinoma (HNSCC). miRNA expression analyses were performed using The Cancer Genome Atlas (TCGA) data accessed from cBioPortal, UALCAN, Santa Cruz University, and Gene Expression Omnibus (GEO). The expression data were correlated with clinicopathological parameters. The functional enrichment was assessed with Gene Set Enrichment Analysis (GSEA). The immunological profiles were assessed using the ESTIMATE tool and RNAseq data from TCGA. All statistical analyses were performed with GraphPad Prism and Statistica. The study showed that both miR-154-5p and miR-154-3p were downregulated in the HNSCC samples and their expression levels correlated with tumor localization, overall survival, cancer stage, tumor grade, and HPV p16 status. GSEA indicated that individuals with the increased levels of miR-154 had upregulated AKT-MTOR, CYCLIN D1, KRAS, EIF4E, RB, ATM, and EMT gene sets. Finally, the elevated miR-154 expression correlated with better immune response. This study showed that miR-154 is highly involved in HNSCC pathogenesis, invasion, and immune response. The implementation of miR-154 as a biomarker may improve the effectiveness of HNSCC treatment.

The expression of TAP1 candidate gene, but not its polymorphism and methylation, is associated with colonic polyp formation in a porcine model of human familial adenomatous polyposis.

In humans, the dysfunction of the adenomatous polyposis coli (APC) gene causes hereditary familial adenomatous polyposis (FAP) and increased risk of colorectal cancer (CRC). The severity of polyposis varies between individuals, but genetic basis for this is in large part unknown. This variability also occurs in our porcine model of FAP, based on an APC1311 mutation (orthologous to human APC1309). Since loss of TAP1 function can lead to CRC in humans, we searched for germline polymorphisms in APC1311/+ pigs with low (LP) and high (HP) levels of polyposis, as well as in wild-type pigs representing six breeds and a commercial line. The distribution of 40 identified polymorphic variants was similar in the LP and HP pigs. In contrast, the TAP1 transcript level was significantly higher in normal colon mucosa of HP pigs than in LP pigs. Moreover, six SNPs showed significant effects on TAP1 promoter activity, but no correlation with severity of polyposis was observed. Analysis of DNA methylation in the promoter region showed that one CpG site differed significantly between LP and HP pigs. We conclude that TAP1 genotype may not itself be associated with polyposis, but our findings concerning its expression suggest a role in the development of polyps.

Porcine familial adenomatous polyposis model enables systematic analysis of early events in adenoma progression.

We compared gene expression in low and high-grade intraepithelial dysplastic polyps from pigs carrying an APC 1311 truncating mutation orthologous to human APC 1309 , analysing whole samples and microdissected dysplastic epithelium. Gene set enrichment analysis revealed differential expression of gene sets similar to human normal mucosa versus T1 stage polyps. Transcriptome analysis of whole samples revealed many differentially-expressed genes reflecting immune infiltration. Analysis of microdissected dysplastic epithelium was markedly different and showed increased expression in high-grade intraepithelial neoplasia of several genes known to be involved in human CRC; and revealed possible new roles for GBP6 and PLXND1. The pig model thus facilitates analysis of CRC pathogenesis.

WNT/ß-catenin signaling affects cell lineage and pluripotency-specific gene expression in bovine blastocysts: prospects for bovine embryonic stem cell derivation.

Despite many attempts, true bovine embryonic stem cells (bESC) still remain elusive. The WNT pathway has been associated with stem cell control in vertebrates and its role in pluripotency maintenance has been proven for several mammalian species, including rodents and primates. Thus, we have aimed to investigate the effect of WNT activation on pluripotency marker gene expression in the inner cell mass (ICM) and the trophectoderm (TE) and to study the derivation potential of primary bESC lines from blastocysts obtained in the presence of the glycogen synthase kinase 3 inhibitor (GSK3i). WNT activity clearly exerted a positive effect on pluripotency gene expression in developing bovine embryos, manifested by upregulation of OCT4, NANOG, REX1, SOX2, c-MYC, and KLF4 in the ICM and downregulation of CDX2 in the TE. However, the prolonged exposition of preimplantation embryos to the GSK3i resulted in reduced potential to form primary ESC-like colonies. The results of bESC derivation experiments allowed us to speculate that the derived cell lines may share features of both naïve and primed ESCs. Similar to mouse epiblast stem cells and human ESCs, the derived lines grew as flat monolayer colonies intolerant to passaging as single cells. JAK/STAT signaling was indispensable for proper colony formation and proliferation, yet LIF alone was inefficient to support self-renewal. Concomitant with the naïve state of mouse ESCs, WNT activity supported by LIF had beneficial effects on cell culture propagation, survival after passage, morphology, and pluripotency-related marker gene expression. Moreover, colonies derived in the presence of LIF and GSK3i maintained KLF4 transcription over several passages, whereas EpiSCs virtually do not express KLF4.