Clinical Significance Of LIN28b And C-myc Expression In Gastric Cancer

Objective:To measure the expression of LIN28B and c-myc in gastric cancer and to determineits association with the clinicopathological characteristics and prognosis of patients withgastric carcinoma.Methods:1、The LIN28B and c-myc protein expression levels in90paraffin blocks of gastriccancer and30normal gastric tissues were determined by substance SPimmunohistochemical technique.2、The patients with gastric carcinoma are follow-up visited by Outpatient、writeletters、telephone,etc to get information of the patients丿recurrence、metastasis anddeath data,and analysis survival of patients.3、 The LIN28B and c-myc mRNA and protein expression levels in23fresh gastriccarcinoma tissues and adjacent normal tissues were measured by real-time PCR andWestern blot analysis.Results:1、The results of immunohistochemistry staining,LIN28B protein was positive in76.7%of the paraffin blocks of gastric cancer and in66.7%of normal gastric tissues. Thedifference was statistically significant (H=4.195， P＜0.05). c-myc protein was positivein81.1%of the paraffin blocks of gastric cancer and in60%of normal gastric tissues.The difference was statistically significant （H=3.887，P＜0.05）.2、LIN28B protein expression was significantly correlated with invasive depth,tumor differentiation, clinical stage, and lymphatic metastasis (P<0.05) but not with age,gender, tumor size, and tumor areas (P>0.05),c-myc protein expression was significantlycorrelated with invasive depth,clinical stage,and lymphatic metastasis (P<0.05) but notwith age, gender, tumor size, tumor areas and tumor differentiation (P>0.05). 3、In the gastric cancer tissue， the expression of LIN28B and c-myc havesignificant correlation (r=0.252, P＜0.05).4、The five-year survival rates of LIN28B-positive patients were47.6％,these weresignificantly lower than those of LIN28B-negative patients which were21.4％(χ2=5.571,P=0.018).5、The LIN28BmRNA （6.33±2.54）levels in fresh gastric carcinoma tissues weresignificantly higher than those in adjacent normal tissues（1.05±0.64),(t=10.129，P＜0.01）.6、The LIN28B protein（0.601±0.22）levels in fresh gastric carcinoma tissues weresignificantly higher than those in adjacent normal tissues（0.124±0.088)，(t=10.671，P＜0.01）.Conclusions:1、LIN28B and c-myc expression is highly correlated with the biological behaviorof gastric carcinoma and thus facilitates the evaluation of gastric carcinoma prognosis.2、The mechanism may be related to gastric cancer stem cells and the circuitsconduction path of LIN28B/let-7/c-myc,it can be expected to become a new effectivefactors to treat gastric cancer.