Rarity of microsatellite genomic instability in B‐cell non‐Hodgkin's lymphomas in hepatitis C virus‐infected patients

• Published in: British journal of haematology 1997-05, Vol.97 (2), p.463-465
• Main Authors: De Vita, Salvatore, Gasparotto, Daniela, Pivetta, Barbara, Vukosavljevic, Tamara, Zagonel, Vittorina, Carbone, Antonino, Boiocchi, Mauro
• Format: Article
• Language: English
• Subjects: Adult; Aged; B-Lymphocytes - virology; Base Sequence; Biological and medical sciences; Cell Transformation, Neoplastic; DNA Replication; DNA, Neoplasm - genetics; DNA, Satellite - genetics; Female; genomic instability; HCV; Hematologic and hematopoietic diseases; Hepatitis C - complications; Humans; Leukemias. Malignant lymphomas. Malignant reticulosis. Myelofibrosis; lymphoma; Lymphoma, B-Cell - genetics; Lymphoma, B-Cell - virology; Male; Medical sciences; microsatellite; Microsatellite Repeats; Middle Aged; Molecular Sequence Data; Phenotype; Polymerase Chain Reaction
• ISSN: 0007-1048; 1365-2141
• DOI: 10.1046/j.1365-2141.1997.252670.x

Several groups have emphasized the likely impli‐cation of the hepatitis C virus (HCV) in a fraction of B‐cell non‐Hodgkin's lymphomas. Since only a minority of patients with HCV infection and monoclonal mixed cryoglobulinaemia develop overt lymphoma, the identification of predisposing factors has relevant clinical implications. The replication error phenotype (RER+), as revealed by widespread microsatellite instability, is caused by defects in DNA mismatch repair genes, and has been frequently disclosed in subsets of B‐cell lymphomas with underlying infection and chronic inflammation. We therefore investigated the occurrence of the RER+ phenotype in a series of eight consecutive B‐cell NHLs in patients with chronic infection by HCV. A polymerase chain reaction‐based assay was used to analyse an extended panel of 15 microsatellite loci. Microsatellite instability was not observed in six tumour samples in any locus; the two remaining cases showed instability at only one locus. Therefore genetic instability by defects in DNA mis‐match repair genes should not represent the general mechanism predisposing to overt lymphoma in HCV‐infected patients. Although a clearer definition of HCV‐related B‐cell disorders should better address future studies on genetic instability in larger series, we recommend additional oncogenetic pathways as the target of further research.