Use of the Polymerase Chain Reaction Technique to Determine c‐myc Expression in Follicular Center Cell Lymphoma

We determined, in a semiquantitative fashion, the level of expression of c-myc in 18 follicular center cell lymphomas and five non-neoplastic lymph nodes using reverse transcription and the polymerase chain reaction technique (RT-PCR). With this method, RNA is extracted from lymph node specimens and reverse-transcribed to produce cDNA, which is then amplified using primers specific for c-myc sequences that span introns, thus precluding amplification of genomic DNA. Amplified products are compared with β2-microglobulin sequences co-amplified in each case as a control for the quality of RNA extracted, RT, and PCR amplification. Using cell lines derived from Burkitt's lymphomas, the RT-PCR method yielded results equivalent to standard Northern blot analysis yet required smaller quantities of tissue. The c-myc transcripts were detected in all lymphoma cases studied (seven high, 11 low expression) and in all non-neoplastic lymph nodes. High or low c-myc expression was based on comparison with non-neoplastic lymph nodes. We conclude that the RT-PCR method is a sensitive, reliable method for measuring gene expression in lymphoma tissues and may be useful for studying the role of c-myc in follicular lymphomas.