Functional analysis of RET with multiple endocrine neoplasia type 2.

BACKGROUND: Multiple endocrine neoplastic type 2 (MEN2) is an endocrine carcinoma syndrome which is caused by a germline activation mutation that occurs during transfection (RET) proto-oncogene transmission. MEN2A patients are affected by RET (C634Y, C634R) mutation; MEN2B patients are affected by RET (M918T) mutation.

AIMS: We aim to identify RET mutations' (C634R and M918T) expression, location, and signaling activation during the disease's progression, which providing a theoretical basis for the study on etiology of multiple endocrine neoplasia.

SETTINGS AND DESIGN: This study was conducted to determine whether RET dysfunction involves an induced mutation into SK-N-MC cells.

MATERIALS AND METHODS: Wildtype RET and mutant RET plasmids (M918T and C634R) were constructed and transfected into SK-N-MC cells, the protein level was detected by Western blot, the efficiency of the transfected cells was detected by real time PCR, and the location of RET protein in cells as-determined by immunofluorescence. SK-N-MC cells with different RET plasmids treated/untreated by GDNF, AKT and ERK1/2 phosphorylation detected by specific antibodies.

RESULTS: We found that C634R mutation could enhance RET protein expression and change the location of the mutated protein and forced it into the nucleus, GDNF treatment alone can only enhance M918T RET phosphorylation level and not impact WT or C614R mutation, and AKT/ERK1/2 pathway can be affected by GDNF treatment.

CONCLUSION: RET dysfunction involves an induced mutation into SK-N-MC cells.