engleski

K-ras and c-myc molecular changes found in pheochromocytomas from Croatian patients

Phaeochromocytomas are neuroendocrine tumors that may be either sporadic or manifestation of a familial cancer syndromes and are derived from neural-crest. In the present study oncogenes ― k-ras and c-myc were investigated in sporadic human phaeochromocytomas in order to identify their involvement. The aim of our investigation was to identify new molecular targets of neuroendocrine carcinogenesis. Pheochromocytoma samples were tested for activating point mutations of k-ras and to the levels of k-Ras and c-Myc protein expression by immunohistochemistry. The results of our analysis showed that point mutations of k-ras were frequent changes, namely 88.9% of phaeochromocytomas harboured k-ras mutations. The k-Ras and c-Myc proteins were up regulated in the phaeochromocytomas we investigated. 61.5% of samples had moderate upregulation of k-Ras expression. Strong expression of k-Ras proteins was not observed in any of our pheochromocytoma cases. Increased levels of Myc protein were shown in 92.3% of cases. Strong upregulation was observed in 6 pheochromocytoma samples and also in the investigated lymph node metastasis (53.8%). Five out of 10 samples with activating k-ras mutation had upregulated levels of both k-Ras and c-Myc. Our findings may contribute to better understanding of phaeochromocytoma molecular profile.

phaeochromocytoma, oncogenes, k-ras, c-myc, signal transduction pathways

nije evidentirano