Cloning And Structure Analysis Of Down-regulated Genes In Human Esophageal Cancer

Esophageal cancer (EC), one of the common human malignancies, is the fourth cause of cancer death in China. Our country has much higher incidence than the other areas and accounts for over half of the total esophageal cancer patients in the world. Previous studies on genetic epidemiology have showed that genetic factors may play an important role in the development of esophageal cancer. However, the susceptibility gene(s) of esophageal cancer has not been identified so far. The molecular mechanisms of the development of esophageal cancer are unclear yet. Molecular genetics of cancer is now shifting from focusing on studying DNA mutations to investigating heredity at both DNA and RNA levels. Cancer epigenetics, an approach to studying heredity of gene expression, comes of age. One focus of cancer research has been on the propensities of tumor suppressors to become loss of expression or down-regulation as a function of tumor initiation and progression. It is important to identify the tumor-associated genes which are down-regulated in tumors. Few down-regulated genes in esophageal cancer have been isolated to date. Cloning of more down-regulated genes and analysis of their expression difference between esophageal cancer tissues and normal esophageal mucosa will be invaluable in furthering our understanding of the molecular events that underlie esophageal cancer development, and in producing more new diagnostic, prognostic and therapeutic targets.1. Isolation of down-regulated genes in human esophageal cancer tissues by using a modified mRNA differential display techniqueA modified differential display PCR (DD-PCR) was developed by using a mixture of dT₁₅A, dT₁₅G and dT₁₅C rather than the conventional single anchored primer, to identify down-regulated genes in human esophageal cancer tissues.