Analysis of BCL2 and MYC expression in non-Hodgkin's lymphomas by in situ hybridization: correlation with chromosome translocations.

We have used an in situ hybridization method for analysis of expression of BCL2 and MYC on cytospun preparations of normal and malignant lymphoid cell lines and tissue sections of normal and malignant lymph nodes. The probes comprised 50-mer antisense oligonucleotides starting at the ATG codons of exon 3 of BCL2 and exon 2 of MYC. We studied the expression of these two genes in frozen tissue sections of biopsy specimens derived from normal and hyperplastic lymph nodes, B-cell lymphomas carrying the t(14;18)(q32;q21) and t(8;14)(q24;q32) translocations, and T-cell lymphomas with clonal chromosome abnormalities. While all proliferating cells expressed both genes, BCL2 expression was increased two- to threefold in follicular lymphomas with t(14;18) and MYC expression was increased two- to four-fold in high-grade lymphomas with t(8;14). These results are consistent with previous data on deregulated expression of these genes obtained from study of lymphoma cell lines carrying the relevant translocations.