Estrogen has anti-colorectal cancer effects which are thought to be mediated by mismatch repair gene (MMR) activity. Estrogen receptor (ER) expression is associated with microRNA (miRNA) expression in ER-positive tumors. However, studies of direct link between estrogen (especially estradiol E2), miRNA expression, and MMR in colorectal cancer (CRC) have not been done. In this study, we first evaluated the effects of estradiol (E2) and its antagonist ICI182,780 on the expression of miRNAs (miR-31, miR-155 and miR-135b) using COLO205, SW480 and MCF-7 cell lines, followed by examining the association of tissue miRNA expression and serum E2 levels using samples collected from 18 colorectal cancer patients. E2 inhibited the expressions of miRNAs in COLO205 cells, which could be reversed by E2 antagonist ICI 182.780. The expression of miR-135b was inversely correlated with serum E2 level and ER-beta mRNA expression in CRC patients' cancer tissues. There were significant correlations between serum E2 level and expression of ER-beta, miR-135b, and MMR in colon cancer tissue. This study suggests that the effects of estrogen on MMR function may be related to regulating miRNA expression via ER-beta, which may be the basis for the anti-cancer effect in colorectal cells.
Adaptor Proteins, Signal Transducing/genetics/metabolism ; Adult ; Aged ; Cell Line, Tumor ; Colorectal Neoplasms/*genetics/metabolism ; DNA Mismatch Repair/*genetics ; Estradiol/analogs & derivatives/blood/*pharmacology ; Estrogen Antagonists/pharmacology ; Estrogen Receptor beta/genetics/*metabolism ; Female ; *Gene Expression Regulation, Neoplastic ; Humans ; Male ; MicroRNAs/genetics/*metabolism ; Middle Aged ; MutS Homolog 2 Protein/genetics/metabolism ; Nuclear Proteins/genetics/metabolism ; RNA, Messenger/biosynthesis

Objective:To analyze and verify the distribution characteristics of radiation dose on the body surface of surgeons in cardiovascular interventional treatment,so as to provide theoretical basis for studying the characteristics of radiation dose and implementing radiation protection correctly.Methods:During cardiovascular interventional surgery,three pieces of lead protective clothing(designated as lead protective clothing A,B,and C)were provided in the room of digital subtraction angiography(DSA)equipment.Each piece of these protective clothing included one lead scarf,one lead vest and one lead apron,and the lead equivalents of them were all 0.5 mmPb.A thermoluminescence dosimeter was placed on the outer surface of the lead protective clothing that was worn by surgeon,and the radiation dose values of the front and back,vertical and horizontal surfaces of the three pieces of lead protective clothing were compared.Results:The measured average values of the front dosimeter of the three pieces of lead protective clothing were respectively(296.2±31.9)mSv,(196.3±20.2)mSv and(299.4±33.0)mSv,which were significantly higher than those of the back of the lead protective clothing,and the differences were statistically significant(Z=-5.522,-5.115,-4.817,Z=-5.522,-5.115,-4.817,P<0.05).The values of abdominal radiation doses on the vertical plane of the three pieces of lead protective clothing were the highest,which were respectively(356.7±58.2)mSv,(217.7±31.8)mSv and(387.4±46.3)mSv.The measured values of the dosimeter on the left side of the horizontal plane of the A,B of lead protective clothing were respectively(341.6±58.5)mSv and(229.1±32.4)mSv,which were all higher than that on the right side,with statistical significances(Z=5.890,9.068,P<0.05).The measured value of the left side of lead protective clothing was respectively higher than that of the middle side and the right side,and the differences were statistically significant(Z=5.846,9.766,P<0.05).Conclusion:The radiation dose of the front of the body surface of surgeon who undergo DSA intervention is significantly higher than that in the back of that,and the radiation dose of the abdomen on the vertical plane of the body is the highest,and the radiation dose of horizontal plane appears a decreasing trend from left to right.The detected dose data and distribution characteristics of radiation can provide research basis for radiation protection.