Immunohistochemical Expression Of GnRH And GnRH-R In Pancreatic Cancer

Some studies showed that GnRH and its receptors exist in many tissue and organs outside of the hypothalamus-pituitary axis, for example, the gonad, placent, the adrenal cortex, the stomach, intestine pancreas and submandibular gland. The GnRH and its receptors exert diverse regulations on the function of these organs. And also, the GnRH and GnRH-R were found in the cancers originated from both the gonad axis and outside the gonad axis such as ovarian cancer, lung cancer, pancreatic cancer and colon cancer. GnRH, when binding with its receptors of cancer, controls the growth of cancer cells. On the other hand, the analogues of GnRH could inhibit the proliferation of some cancer cells. Pancreatic cancer is a malignancy in which the endocrinal and exocrine gland coexists. Except for surgery, its treatment is limited. Although GnRHa have been reported being used in the treatment of pancreatic cancer, there has not yet been reports about the expression of GnRH and its receptor in pancreatic cancer in China. By immunohistochemical method, the study observed the expression of GnRH and its receptor in pancreatic cancer of different differentiation degree, in order to ananlyze the relations between GnRH and its receptors and the degree of pancreatic cancer cell proliferation.OBJECTIVE:To observe the expression of GnRH and its receptor in pancreatic cancer, to analyze the relationship between GnRH and its receptors and the proliferation degree of pancreatic cancer and to lay histological foudation for endocrinal therapy of pancreatic cancer.METHOD:By using immunohistochemical techniques of streptavidin-peroxidase (S-P) method, the expressions of GnRH and its receptor in 46 patients'pancreatic cancer tissues were observed, and its correlations were studied. There are 20 cases of well differentiated pancreatic cancer, 16 cases of moderately differentiated pancreatic cancer and 10 cases of low differentiated pancreatic cancer.RESULTS:1. Immunohistochemical staining showed GnRH located at the membrane and cytoplasm of pancreatic cancer cell, the positive expression rate of well differentiated pancreatic cancer was 78.55%, which was remarkablely higher than that of moderately differentiated pancreatic cancer(59.31%, P < 0.001) and that of low differentiated pancreatic cancer(50%, P < 0.001).2. Immunohistochemical staining showed GnRH-R located at the membrane and cytoplasm of pancreatic cancer cell, the positive expression rate of well differentiated pancreatic cancer was 82.50%, which was remarkablely higher than that of moderately differentiated pancreatic cancer(68.88%, P < 0.001) and that of low differentiated pancreatic cancer(47.20%, P < 0.001). Expression of GnRH-R in pancreatic cancer with different differentiation was acoorded with the expression of GnRH.CONCLUSION:Immunohistochemical staining showed the positive expression rate of GnRH and GnRH receptor in pancreatic cancer was over 50%. The positive expression rate of GnRH and GnRH receptor is relatived with the differentiation of pancreatic cancer. The better differentiation of pancreatic cancer, the higher GnRH and GnRH receptor positive rate, and vice versa. This work proposed that GnRH and its receptor may be involved in the occurrence and development of malignant tumors of the pancreas and inhibit the proliferation of tumor cells, thereby promoting the differentiation of pancreatic cancer cells. This needs further study.