Isolation And Cloning Of The DNA Fragments Related To The Cardia Carcinoma And The Studies On Their Clinical Significance

Cardia carcinoma is one of the most common digestive cancers in China. Because there is no effective approaches for the early diagnosis, the prognosis is very poor. Recent studies on the carcinogenesis reveals that neoplasms arise and progress through the accumulation of various genetic alterations. Therefore, isolation and cloning the related genes or gene fragments involved in the initiation and development of the cardia carcinoma is of great clinical significance for the early diagnosis and treatment of this disease.In the present study, we have used a novel technique AP-PCR and some other molecular biological methods to detect tumor-specific somatic genetic alterations by comparison of the AP-PCR fingerprints from tumor and normal tissue of the same individual in 50 cases. Three DNA fragments (named X,Y,Z) deleted in tumor tissue were isolated and cloned. The length of these sequences were 449bp, 316bp and 323bp respectively. Sequence analysis showed that DNA fragments X and Z had no remarkable similarity to the known sequences in the Public Database of GenBank, which indicates that these two fragments may represent novel genes. Whereas, fragment Y showed a significant homology (98%) to a cDNA sequence which was newly discovered in human brain tissue by a group in Baylor College of Medicine in USA. Furthermore, these three fragments were all first found deleted in the cardia carcinoma, so we speculated that they may...