Frequent mutations of the CA simple sequence repeat in intron 1 of EGFR in mismatch repair-deficient colorectal cancers.

Aim: To investigate the polymorphic simple sequence repeat in intron 1 of the epidermal growth factor receptor gene (EGFR) (CA-SSR I), which is known to affect the efficiency of gene transcription as a putative target of the mismatch repair (MMR) machinery in colorectal tumors.

Methods: The CA-SSR I genotype was analyzed in a total of 86 primary colorectal tumors, selected upon their microsatellite instability (MSI) status [42 with high frequency MSI (MSI-H) and 44 microsatellite stable (MSS)] and their respective normal tissue. The effect of the CA-SSR I genotype on the expression of the EGFR gene was evaluated in 18 specimens using quantitative real-time reverse transcription PCR and immunohistochemistry.

[von Hippel-Lindau syndrome: molecular diagnosis of two Lebanese families and analysis of the genotype-phenotype correlation].

The von Hippel-Lindau syndrome (VHL) is a dominantly transmitted hereditary disorder associating multisystemic tumors affecting mainly the central nervous system, the kidneys, the pancreas, as well as pheochromocytomas. Mutations of the tumor suppressor gene VHL on chromosome 3 are responsible for the disease. This article reports for the first time the study of two Lebanese VHL affected families, presenting particularly hemangioblastomas of the central nervous system.