| Theme |
Molecular Biology & GI Tract |
| Title |
Molecular Alterations in Esophageal Cancer |
| Author |
Naohiro Tomita |
Department of Surgery II, Osaka University Medical School |
| Author |
Tadashi Ohnishi |
Department of Surgery II, Osaka University Medical School |
| [ Summary ] |
Adenoma and carcinoma in adenoma of the colorectum include different grades of dysplasia in the same polyp and are therefore thought to be ideal clinical materials for genetic analysis of the early phase of the "adenoma-carcinoma sequence". Micro-analysis of these materials revealed that p53 gene mutations are involved in the key transition in malignant transformation. It was also shown that the K-ras gene mutation has considerable heterogeneity in the same polyp and that cells with K-ras mutations do not always have a growth advantage. At present, the analysis of p53 mutation in colorectal polyps is useful for diagnosing border-line malignancy.
It is anticipated that the molecular mechanisms of colorectal carcinogenesis, including the problem of the "de novo" pathway, will be clarified with the acquisition of additional information regarding various genetic alterations, such as DNA replication errors and disorders of cell cycle regulators. |