TRAF4, a signaling protein overexpressed in human carcinomas

TRAF4 is a member of the TNF receptor-associated factor family which was identified due to its overexpression by gene amplification in breast carcinomas. The analysis of TRAF4 expression was extended to 13 different tumor types and was performed by immunohistochemistry on tissue micro-arrays. TRAF4 was overexpressed in 48% of all cases. The highest percentages of cases showing TRAF4 overexpression were in lung, pancreas, breast and ovary carcinomas. TRAF4 localized in the cytoplasm in 79% of the positive tumors, in the nucleus in 11% and in both the cytoplasm and the nucleus in the remaining cases. Altogether, this protein represents a novel candidate tumor marker of human carcinomas.