A Study of Epigenetic Alteration of the Bone Morphogenetic Protein-2 Gene in Human Colorectal Cancer

PURPOSE: Bone morphogenetic proteins (BMPs) are members of the transforming growth factor-beta family and play an important role in cellular growth. Recent reports suggest that exogenous bone morphogenetic protein-2 (BMP-2) acts as an antiproliferative agent in a variety of cell lines. We will study whether BMP-2 is altered in human colorectal cancer. METHODS: We analyzed 40 colorectal cancer cases and 6 colorectal cancer cell lines by using reverse transcription-polymerase chain reaction (RT-PCR) to determine the expression of BMP-2. RESULTS: Thirteen of 40 colorectal cancers (33%) and 3 of 6 colorectal cancer cell lines (50%) revealed decreased expression of BMP-2. The rates of decreased expression were 0% (0/7), 42.1% (8/19), 28.6% (2/7), 33.3% (2/6), and 100% (1/1) in stages I, II, III, and IV, respectively. Histologically, the rates were 33.3% (2/6), 32.2% (10/21), 50% (1/2), and 0% (0/1) in well-differentiated, moderately-differentiated, poorly-differentiated and mucinous cancers, respectively. As for location, the rates for colon and rectal cancers were 27.8% (5/18) and 36.4% (8/22), respectively. We identified methylation in the CpG island of the BMP-2 gene in 60% of colorectal cancer cells and in 50% of colorectal cancer cell lines. The 13 cases without BMP-2 gene expression showed no significant correlation with clinicopathological factors. Epigenetic silencing through DNA methylation is one of the key steps during carcinogenesis. CONCLUSION: We found, through an analysis using the methylation-specific polymerase chain reaction technique, CpG island methylation of the BMP-2 promoter region in colorectal cancer. Thus, aberrant BMP-2 methylation and the resultant loss of BMP-2 expression may be related to colorectal carcinogenesis.

Effect of Recombinant Fragment of Fibronectin on the Cellular Functions of Human Bone Marrow-Derived Mesenchymal Stem Cells / 대한정형외과연구학회지

PURPOSE: We investigated the effects of recombinant 9-10th type III repeat of fibronectin (rhFNIII9-10) on the adhesion, proliferation, and the osteogenic differentiation of human bone marrow-derived mesenchymal stem cells(hMSCs). MATERIALS AND METHODS: Adhesion and blocking assay for hMSCs were performed on the plates which had been coated with 100 microgram/ml rhFNIII9-10 or fibronectin. hMSCs seeded on the precoated plates were cultured in the osteogenic media for 3 weeks. MTS(Dimethylthiazole carboxymethoxyphenyl sulfophenyl tetrazolium compound) assay for the cell number, [Methyl-3H] thymidine incorporation study, alkaline phosphatase activity assay, calcium content assay and RT-PCR for alkaline phosphatase, osteopontin, cbfa-1, and type I collagen were performed during the osteogenic differentiation. RESULTS: hMSCs showed significantly increased adhesion to rhFNIII9-10-coated plates and fibronectin-coated plates. A monoclonal antibody to the integrin alpha 5 beta 1 inhibited adhesion to rhFNIII9-10-coated plates and fibronectin-coated plates in dose-dependent manner. hMSCs seeded on the rhFNIII9-10-coated plates showed increased proliferation during the osteogenic differentiation. However, there was no significant difference in the alkaline phosphatase activity, calcium content and expression levels of mRNAs for alkaline phosphatase, osteopontin, cbfa-1, and type I collagen of hMSCs seeded on the rhFNIII9-10-coated plates. CONCLUSION: rhFNIII9-10 stimulates hMSCs adhesion and increases hMSCs proliferation during the osteogenic differentiation. Although osteogenic differentiation is not promoted, adsorption of rhFNIII9-10 onto appropriate biomaterials can enhance integrin-mediated hMSCs adhesion and proliferation. This biomolecular engineering strategy represents a robust approach to increase biofunctional activity and integrin specificity of hMSCs.

Biological Effects of Fibronectin Type III 10 domain on Human Osteoblast-like cells / 대한치주과학회지

No abstract available.