Proteomic profile in familial breast cancer patients

Breast cancer is the most common form of cancer affecting women, and the strongest risk factor remains family history. Although screening in asymptomatic women seems able to reduce breast-cancer related mortality, it is of limited usefulness in young women and patients with familial breast cancer syndrome. New diagnostic tools useful for breast cancer management are urgently needed. The aim of the present paper is to look for new candidate tumor markers useful for diagnosis in these patients.

In this prospective study 292 serum samples (100 from healthy people, 100 from sporadic breast cancer patients and 92 from familial breast cancer patients) were analyzed by SELDI-TOF-MS. All samples both from cancer patients and healthy subjects were run in duplicate and randomly spotted on CM10 and IMAC30 protein chip array. Data were analyzed using the expression differential mapping (EDM) tool, decisional tree and multivariate analysis. A further in silico investigation was performed in order to hypothesize the identity of evidenced peptides.

EDM highlighted thirteen and sixteen significant differentially expressed peaks by CM10 and IMAC30 protein chip respectively. Subsequent analysis showed that two peaks at m/z 11730 and 5066 were differentially expressed in sporadic and familial breast cancer patients respectively, while a peak at m/z 8127 was overexpressed only in familial breast cancer patients. The diagnostic power of protein peaks was tested by decisional tree; sensitivity and specificity ranged from 17% to 91.67%.

We show that the serum profile of familial breast cancer patients was different when compared with that of sporadic breast cancer patients. We hypothesized the identity of the most significant peaks, and further studies are now planned in order to definitively establish the identity.