elastin and Carcinogenesis

Colorectal cancer (CRC) is the most common cancer and a leading cause of death worldwide. Extracellular matrix (ECM) proteins regulate tumor growth and development in CRC. Elastin (ELN) is a component of ECM proteins involved in the tumor microenvironment. However, the role of ELN in CRC remains unclear.. In this study, we analyzed ELN gene expression in tumors from CRC patients and adjacent non-tumor colon tissues and healthy controls from two existing microarray datasets. ELN protein was measured in human normal colon cells and colon cancer epithelial cells and tumor development was assessed in colon epithelial cells cultured in medium with or without ELN peptide on plates coated with ELN recombinant protein. Control plates were coated with PBS only.. We found ELN gene expression was increased in tumors from CRC patients compared to adjacent non-tumor tissues and healthy controls. ELN protein was increased in cancer cells compared to normal colon epithelial cells. Transforming growth factor beta (TGF-β) was a key cytokine to induce production of ECM proteins, but it did not induce ELN expression in colon cancer cells. Matrix metalloproteinase 9 (MMP9) gene expression was increased, but that of MMP12 (elastase) did not change between CRC patients and control. Tissue inhibitor of metalloproteinases 3 (TIMP3) gene expression was decreased in colon tissues from CRC patients compared to healthy controls. However, MMP9, MMP12 and TIMP3 proteins were increased in colon cancer cells. ELN recombinant protein increased proliferation and wound healing in colon cancer epithelial cells. This had further increased in cancer cells incubated in plates coated with recombinant ELN coated plate and in culture media containing ELN peptide. A potential mechanism was that ELN induced epithelial mesenchymal transition with increased alpha-smooth muscle actin and vimentin proteins but decreased E-cadherin protein. Tumor necrosis factor alpha (TNF) mRNA was also increased in CRC patients compared to controls. ELN recombinant protein induced further increases in TNF protein in mouse bone marrow derived macrophages after lipopolysaccharide stimulation.. These data suggest ELN regulates tumor development and the microenvironment in CRC.

Topics: Animals; Caco-2 Cells; Carcinogenesis; Cell Movement; Cell Proliferation; Colorectal Neoplasms; Elastin; Epithelial-Mesenchymal Transition; Extracellular Matrix; Female; Gene Expression; Gene Expression Regulation, Neoplastic; Humans; Matrix Metalloproteinase 12; Matrix Metalloproteinase 9; Mice; Mice, Inbred C57BL; Recombinant Proteins; Tissue Inhibitor of Metalloproteinase-3; Tumor Microenvironment; Tumor Necrosis Factor-alpha

Epithelial changes observed in actinic cheilitis (AC) and lower lip squamous cell carcinoma (LLSCC) have been studied using different markers in order to observe diagnostic and prognostic factors for both lesions. The aim of the present study was to analyze Ki-67, TGF-β1, and elastin content in AC and LLSCC to determine the possible role of these proteins in lip carcinogenesis. Medical records of 29 cases of AC and 53 cases of LLSCC were analyzed. Lesions were classified according histological pattern and submitted to immunostaining for Ki-67, TGF-β1, and elastin. Different percentages of Ki-67-positive cells were found in AC depending on the degree of epithelial dysplasia (p < 0.01). An association was also found between the percentage of Ki-67-positive cells and tumor grade in LLSCC (p < 0.01). An inverse correlation was found between Ki-67 and TGF-β1 in AC and LLSCC (p < 0.01). Elastosis was thinner and more discontinuous in LLSCC in comparison to AC, and this difference in the elastin immunolabeling pattern was statistically significant between groups (p < 0.01). The present findings indicate that changes in Ki-67 and TGF-β1 content contribute to lip carcinogenesis. Furthermore, elastin content reflects changes in the extracellular matrix in both AC and LLSCC.

Topics: Adult; Aged; Carcinogenesis; Carcinoma, Squamous Cell; Elastin; Female; Humans; Immunohistochemistry; Ki-67 Antigen; Lip Neoplasms; Logistic Models; Male; Middle Aged; Transforming Growth Factor beta1