Colorectal cancer prognosis get worse with advancement of disease into metastatic stage. There is a pertinent need to develop prognostic biomarkers that can be used for personalized and precision medicine. Alternative splicing provides an insight into understanding of changes at isoform expression level which may not be evident at gene level. In this direction, we utilized our prior knowledge about significant alternatively spliced genes and chose ADAM12 and MUC4 for further characterization in a metastatic cell line model. These genes were found to be good prognostic indicators in The Cancer Genome Atlas database. We studied the gene organization and designed primers to specifically amplify a group of isoforms. Differential expression of these group of isoforms was observed in normal, primary and metastatic colorectal cancer cell lines. We further validated the results using sanger sequencing. Isoform expression was found to respond to the 5-fluorouracil treatment. RNAseq analysis of the cell lines further validated the differential expression of gene isoforms. Successful detection of ADAM12 and MUC4 in cell lysates varied according to the antibody used which may reflect differential expression of isoforms. This comprehensive study underscores the importance of studying alternatively spliced isoforms and their probable used as prognostic or predictive biomarkers.

Background: Understanding in vitro expansion of OKF6/TERT-2 oral epithelial cells is important for studying molecular biology of disease and pathology affecting the oral cavity. The media used for any cell culture is paramount in terms of efficient output. Therefore, this study aims to compare two different media for OKF6/TERT-2 cultures: Keratinocyte Serum-Free Medium (KSFM) and a composite medium comprised of DMEM/F-12 mixed with KSFM (referred to as DFK). For application purposes, this investigation also compares the toxicological effects of flavored electronic cigarette liquids (E-liquids) on OKF6/TERT-2 cultures grown in both media. Methods: Cells were grown in KSFM and DFK media and cellular growth, morphology, gene expression of mucins and tight junctions, as well as wound-healing were determined. Additionally, cellular viability and cytotoxicity were indexed after E-liquid exposures. Results: While overall cellular morphologies remained unaltered, cells grown in DFK reached confluency faster. Except for claudin-1, there is no appreciable difference in expression of the other genes tested. Additionally, cultures in DFK appear more sensitive to E-liquids ± flavors. Conclusions: DFK is an alternative medium for cultivation of OKF6/TERT-2 cells to study molecular biology of disease and pathology, such as their responses to E-liquids ± flavors.

Endotoxins are toxic substances that widely exist in the environment and can enter the intestine with food and other substances. Intestinal epithelial cells are protected by a mucus layer that contains MUC2 as its main structural component. However, a detailed understanding of the mechanisms involved in the function of the mucus barrier in endotoxin penetration is lacking. Here, we established the most suitable proportion of Caco-2/HT-29 co-culture cells as a powerful tool to evaluate the intestinal mucus layer. Our findings significantly advance current knowledge as focal adhesion and ECM-receptor interaction were identified as the two most significantly implicated pathways in MUC2 small interfering RNA (siRNA)-transfected Caco-2/HT-29 co-culture cells after 24 h of LPS stimulation. When the mucus layer was not intact, LPS was found to damage the tight junctions of Caco-2/HT29 co-cultured cells. Furthermore, LPS was demonstrated to inhibit the integrin-mediated focal adhesion structure and damage the matrix network structure of the extracellular and actin microfilament skeletons. Ultimately, LPS inhibited the interactive communication between the extracellular matrix and the cytoskeleton for 24 h in the siMUC2 group compared with the LPS(+) and LPS(-) groups. Overall, we recognized the potential of MUC2 as a tool for barrier function in several intestinal bacterial diseases.