NATURAL-KILLER-CELL FUNCTION AND GENETIC INSTABILITY IN UNAFFECTED INDIVIDUALS FROM BREAST-CANCER FAMILIES

Several recent reports highlight the importance of modifying factors i n determining the risk for cancer of a person carrying a mutant allele of a tumour susceptibility gene. The study of two such risk modifying factors namely, natural killer (NK) cell function and constitutional cytogenetic anomalies in members of families with familial breast canc er is presented in this paper. We observed that, compared to healthy c ontrols, a significant proportion of unaffected persons from breast ca ncer families not only display lower NK cell function or genetic insta bility alone, but also in conjunction. The significance of these obser vations is discussed. We propose that amongst the unaffected members, persons with lower NK cell function as well as constitutive cytogeneti c anomalies may be at a higher risk for cancer, The need for a set of suitable biomarkers to identify individuals at high risk from familial breast cancer families has been recognized for many years. Constituti onal cytogenetic anomalies, otherwise seen in breast tumours, have als o been observed in lymphocyte cultures from unaffected persons from su ch families. Lowered NK cell function has previously been demonstrated in first degree relatives of cancer patients. Both these parameters h ave been implicated in determining the risk of developing malignancy. In the present study these aspects have been investigated simultaneous ly in order to assess their utility as potential biomarkers. (C) Lippi ncott-Raven Publishers.