EPSTEIN-BARR-VIRUS IN EPITHELIAL-CELL TUMORS - A BREAST-CANCER STUDY

The human herpes virus Epstein-Barr (EBV) is clearly associated with A frican Burkitt's lymphoma and the undifferentiated form of nasopharyng eal carcinoma, although its role in oncogenesis is still poorly define d, Recently EBV has been implicated in other types of lymphomas, as we ll as in some nonlymphomatous neoplastic processes, Its possible assoc iation with human breast cancer has been investigated here, DNA from 9 1 cases of breast carcinoma and blood samples from the same patients w ere amplified with the PCR over a region in the EBV BarnHIW major repe at sequence following a single-step amplification protocol, Nineteen s amples (21%) were found to be positive; 10 samples of blood (only 3 of them from patients with EBV-positive tumors) were found by the adopte d protocol to contain EBV DNA, Another series of PCR amplifications us ing primers covering a unique (nonreiterated) fragment in BamHIC encod ing the EBERs (two short nonpolyadenylated RNAs generally highly expre ssed in cells latently infected with EBV) confirmed these findings, A good correlation between the two sets of experiments was observed, and only five differences in results were obtained on samples tested, Irt situ hybridization was carried out using BamHIW biotinylated DNA prob es or EBER-1 digoxigenin-labeled riboprobes with the aim of confirming as well as localizing the signal to the epithelial cell, Twelve secti ons (63%) among the PCR-positive samples were found positive by in sit s hybridization with the DNA probe, and six (31.5%) sections were foun d with the RNA probe, Twenty-one samples from benign breast tumors or normal breast tissue were used as controls for PCR amplification in th is study, none of which was found positive, This is the first known re port showing positive results for EBV in breast cancer, No statistical association was found in these studies between the presence of EBV an d the histological type of the tumor, however, Its role therefore rema ins for the moment unknown, as well as does the significance of the as sociation of EBV with only a subset of the cases.