The Study On Expression Of Cytokeratin-20 MRNA In Gastric Carcinoma Tissue And Micrometastasis Of Gastric Carcinoma

Gastric carcinoma is the most frequently occurring cancer arid its morbidity and mortality rates are the highest among malignant diseases. Radical operation is the best treatment for this tumor currently with 5 year survival rate reaching 40%-50% in advanced stage and 90% in early stage. However, patients will subsequently die of distant metastases or local recurrence. Therefore it is obviously necessary to determine metastases as early as possible. As the wide variety of methods of detecting metastases bears testimony the fact that none is perfect in the present time, there is a clear need for more sensitive approaches to provide accurate prognostic information. Recently, a new technique (reverse transcriptase polymerase chain reaction, RT-PCR) is developed to detect tumor cells in peripheral blood, lyinpbnodes or bone marrow. It has been reported this method could detect one tumor cell in a background of l0~-l0~ normal cells in various cancer tissues, which arc significantly more sensitive than conventional cytology. It has become possible to detect micrometastases in different tissues. This method may be of great clinical significance, not only for staging tumor, predicting recurrence and metastases and selecting therapeutic methods, but also for confirming the outcome of therapeutics. Selection of appropriate target RNA, which be expressed in tumor cells but not in normal cells, play a pivotal role in using RT-PCR to detect micrometastases accurately. Some study had indicated that cytokeratin 4 20 (CK2O) located specifically in intestinal epithelial cells and was a good marker for detecting micrometastases of intestinal carcinomas. However, it had not been reported whether this specific marker present in gastric cancer cells as yet. Basing on these knowledge, we have used RT-PCR to assay quantitatively CK2OmRNA expressing in cancer tissues, lympbnades or peripheral blood of 32 patients with gastric carcinoma. Our present study includes as follows: Part I The study expression of CK2O mRNA in gastric carcinoma tissue and relevanceto the pathological classifications. Aim:To assay for specific expression of CK2O mRNA in gastric carcinoma tissue and investigate relevance to the pathological classifications. Methods: Using RT-PCR method for detecting CK2OmRNA expressing in gastric cancer tissue and quantitying by computer picture process method. Results:l.of 32 gastric carcinoma tissue specimens, expression rate was 81% (26/32 specimens); 2.expression quantity ranged 0%-9l%, mean 63%; 3.high expression rate was presented in signet ring cells carcinoma, low梔ifferentiated adenocarcinoma and tubular adenocarcinoma, whereas no expression in mucoid carcinoma (3 specimens); 4.mean expression quantity was 67?3%,58?9%and 62?1% in signet ring cells carcinoma, low differentieted adenocarcinoma and tubular adenocarcinoma, there are no significant difference between them (P>0.05). 5 Conclusion:l.the high level of expression of CK2OmRNA was present in gastric carc...