Relationship Between TAMs, TGF-β1and Epithelial Mesenchymal Transition In Colorectal Cancer And The Study Of The Mechanism Between Them

ObjectiveFirst， to analyze the dependability between tumor associatedmacrophages (TAMs)， transforming growth factor beta1(TGF-β1)expressed in colorectal cancer and epithelial mesenchymal transition(EMT) through clinical pathology specimens. Second， to investigateTGF-β1how to induce EMT on SW620cells in vitro experiments.MethodsFirst，Immunohistochemistry was used to detect the expression ofTAMs marked by CD68， TGF-β1， E-cadherin and Vimentin in80colorectal cancer specimens and matched adjacent non-canceroustissue specimens. Second， Western Blot was also used to detect theexpression of E-cadherin and Vimentin protein in SW620cells in vitrowhich had been used TGF-β1to deal and compared with non-TGF-β1dealt group.ResultsThe positive count of TAMs， positive expression of TGF-β1，E-cadherin and Vimentin in colorectal cancer were significantlydifferent from those in adjacent non-cancerous tissue(30.6±8.2vs16.4±7.2，72.5%vs28.8%，38.8%vs80.0%，47.5%vs0andall P<0.01). Count of TAMs，TGF-β1，E-cadherin and Vimentin protein expression correlate with the degrees of differentiation， depth ofinvasion， Duke stages and lymph nodes metastasis in colorectalcancer and all P<0.05. E-cadherin protein was negatively correlatedwith count of TAMs (r=-0.64， P <0.01) while TGF-β1expression andVimentin protein was positive correlated with count of TAMs (r=0.54and0.62， P <0.01). Dependability exists between positive expressionof TGF-β1and negative expression of E-cadherin， r=0.52， P<0.01；which also presents between positive expression of TGF-β1andpositive expression of Vimentin， r=0.24， P<0.05. The expression ofE-cadherin protein in SW620dealt with TGF-β1gradually decreasedby time passing and the concentration of TGF-β1increasing. Therewas significant difference between experiment groups and controlgroups and all P<0.05， E-cadherin has the lowest expression at10μg/L，72h. The Vimentin protein was just contrast to E-cadherin，all P<0.05and has the highest expression at10μg/L，72h.ConclusionsThe infiltration of TAMs and TGF-β1overexpressed causedinflammatory environment promote the invasion， metastasis and thedevelopment of EMT in colorectal cancer. EMT in SW620cells wasderived by TGF-β1.