Mutational Profiles Reveal an Aberrant TGF-β-CEA Regulated Pathway in Colon Adenomas.

Mutational processes and signatures that drive early tumorigenesis are centrally important for early cancer prevention. Yet, to date, biomarkers and risk factors for polyps (adenomas) that inordinately and rapidly develop into colon cancer remain poorly defined. Here, we describe surprisingly high mutational profiles through whole-genome sequence (WGS) analysis in 2 of 4 pairs of benign colorectal adenoma tissue samples. Unsupervised hierarchical clustered transcriptomic analysis of a further 7 pairs of adenomas reveals distinct mutational signatures regardless of adenoma size. Transitional single nucleotide substitutions of C:G\u3eT:A predominate in the adenoma mutational spectrum. Strikingly, we observe mutations in the TGF-β pathway and CEA-associated genes in 4 out of 11 adenomas, overlapping with the Wnt pathway. Immunohistochemical labeling reveals a nearly 5-fold increase in CEA levels in 23% of adenoma samples with a concomitant loss of TGF-β signaling. We also define a functional role by which the CEA B3 domain interacts with TGFBR1, potentially inactivating the tumor suppressor function of TGF-β signaling. Our study uncovers diverse mutational processes underlying the transition from early adenoma to cancer. This has broad implications for biomarker-driven targeting of CEA/TGF-β in high-risk adenomas and may lead to early detection of aggressive adenoma to CRC progression

Vitamin D Deficiency Promotes Liver Tumor Growth in Transforming Growth Factor-β/Smad3-Deficient Mice Through Wnt and Toll-like Receptor 7 Pathway Modulation.

Disruption of the TGF-β pathway is associated with liver fibrosis and suppression of liver tumorigenesis, conditions associated with low Vitamin D (VD) levels. However, potential contributions of VD to liver tumor progression in the context of TGF-β signaling remain unexplored. Our analyses of VD deprivation (VDD) in in vivo models of liver tumor formation revealed striking three-fold increases in tumor burden in Smad3(+/-) mice, with a three-fold increase in TLR7 expression compared to controls. ChIP and transcriptional assays confirm Smad3 binding at two TLR7 promoter SBE sites. Molecular interactions between TGF-β pathway and VDD were validated clinically, where an absence of VD supplementation was associated with low TGF-β pathway member expression levels and β-catenin activation in fibrotic/cirrhotic human liver tissues. Subsequent supplementing VD led to restoration of TGF-β member expression with lower β-catenin levels. Bioinformatics analysis provides positive supportive correlation between somatic mutations for VD-related genes and the TGF-β pathway. We conclude that VDD promotes tumor growth in the context of Smad3 disruption, potentially through regulation of TLR7 expression and β-catenin activation. VD could therefore be a strong candidate for liver cancer prevention in the context of aberrant Smad3 signaling

Alcohol, Stem Cells and Cancer.

Dosage, gender, and genetic susceptibility to the effects of alcohol remained only partially elucidated. In this review, we summarize the current knowledge of the mechanisms underlying the role of alcohol in liver and gastrointestinal cancers. In addition, two recent pathways- DNA repair and TGF-β signaling which provide new insights into alcohol in the regulation of cancers and stem cells are also discussed here

A Pan-cancer analysis reveals high-frequency genetic alterations in mediators of signaling by the tgf-β superfamily

We present an integromic analysis of gene alterations that modulate transforming growth factor β (TGF-β)-Smad-mediated signaling in 9,125 tumor samples across 33 cancer types in The Cancer Genome Atlas (TCGA). Focusing on genes that encode mediators and regulators of TGF-β signaling, we found at least one genomic alteration (mutation, homozygous deletion, or amplification) in 39% of samples, with highest frequencies in gastrointestinal cancers. We identified mutation hotspots in genes that encode TGF-β ligands (BMP5), receptors (TGFBR2, AVCR2A, and BMPR2), and Smads (SMAD2 and SMAD4). Alterations in the TGF-β superfamily correlated positively with expression of metastasis-associated genes and with decreased survival. Correlation analyses showed the contributions of mutation, amplification, deletion, DNA methylation, and miRNA expression to transcriptional activity of TGF-β signaling in each cancer type. This study provides a broad molecular perspective relevant for future functional and therapeutic studies of the diverse cancer pathways mediated by the TGF-β superfamily

Identification of Potential Meniere’s Disease Targets in the Adult Stria Vascularis

The stria vascularis generates the endocochlear potential and is involved in processes that underlie ionic homeostasis in the cochlear endolymph, both which play essential roles in hearing. The histological hallmark of Meniere’s disease (MD) is endolymphatic hydrops, which refers to the bulging or expansion of the scala media, which is the endolymph-containing compartment of the cochlea. This histologic hallmark suggests that processes that disrupt ion homeostasis or potentially endocochlear potential may underlie MD. While treatments exist for vestibular symptoms related to MD, effective therapies for hearing fluctuation and hearing loss seen in MD remain elusive. Understanding the potential cell types involved in MD may inform the creation of disease mouse models and provide insight into underlying mechanisms and potential therapeutic targets. For these reasons, we compare published datasets related to MD in humans with our previously published adult mouse stria vascularis single-cell and single-nucleus RNA-Seq datasets to implicate potentially involved stria vascularis (SV) cell types in MD. Finally, we provide support for these implicated cell types by demonstrating co-expression of select candidate genes for MD within SV cell types.Intramural Research Program of the NIH, NIDCD DC000088European Commission PI17-1644FIBAO PE-0356-201

Long non-coding RNA LINC01419 mediates miR-519a-3p/PDRG1 axis to promote cell progression in osteosarcoma

Abstract Background Osteosarcoma (OS) is one of the most aggressive malignancies with mortality rate worldwide. Accumulating evidence has revealed that long noncoding RNAs (lncRNAs) exert important functions in regulation of cancer initiation and progression. Recently, long intergenic non-protein coding RNA 1419 (LINC01419) has been reported to function as an oncogene in several cancers. However, its role in OS has not been explored yet. Methods qRT-PCR and western blot analyses were implemented to determine the expression of genes. The function of OS cells was assessed through colony formation, EdU, JC-1, TUNEL, transwell, and immunofluorescence (IF) assays. FISH and subcellular fractionation assays were conducted to estimate the localization of LINC01419 in OS cells. The interaction between genes was validated through luciferase reporter and RNA pull down assays. Results LINC01419 expression was elevated in OS tissues and cells. Functionally, LINC01419 accelerated OS cell proliferation, motility and EMT. In vivo assay showed that silencing LINC01419 hindered the growth of OS tumors. Mechanistic investigation unveiled that LINC01419 acted as a competing endogenous RNA (ceRNA) to augment PDRG1 expression by miR-519a-3p sequestration. Rescue assays verified the oncogenic effect of LINC01419/miR-519a-3p/PDRG1 axis on OS development. Conclusion LINC01419 mediates malignant phenotypes in OS by targeting miR-519a-3p/PDRG1 axis. </jats:sec

Basic Helix-Loop-Helix Transcription Factor Twist1 Inhibits Transactivator Function of Master Chondrogenic Regulator Sox9

Canonical Wnt signaling strongly inhibits chondrogenesis. Previously, we identified Twist1 as a critical downstream mediator of Wnt in repression of chondrocyte differentiation. However, the mechanistic basis for the antichondrogenic activity of Twist1 has not heretofore been established. Here, we show that Twist1 suppresses cartilage development by directly inhibiting the transcriptional activity of Sox9, the master regulator of chondrogenesis. Twist1, through its carboxyl-terminal Twist-box, binds to the Sox9 high mobility group DNA-binding domain, inhibiting Sox9 transactivation potential. In chondrocyte precursor cells, Twist1, in a Twist-box-dependent manner, inhibits Sox9-dependent activation of chondrocyte marker gene expression by blocking Sox9-enhancer DNA association. These findings identify Twist1 as an inhibitor of Sox9 and further suggest that the balance between Twist1 and Sox9 may determine the earliest steps of chondrogenesis