Plasma DNA Methylation of p16 and shp1 in Patients with B-Cell Non-Hodgkin Lymphoma

To discuss the clinical implications of cell free DNA, methylation status of the p16 and shp1 genes in plasma DNA from patients with B-NHL were analyzed. Methylation specific polymerase chain reaction (MSP) was used to detect the methylation status of these genes in plasma, peripheral blood leukocytes (PBLs), and formaldehyde-fixed, paraffin-embedded (FFPE) tumor tissues of 73 B-NHL patients. Results showed methylation frequencies of p16 in plasma, PBLs, and FFPE tumor tissues of B-NHL patients were 37%(27/73), 16% (12/73), 39% (16/41); Whereas those of shp1 were 47% (34/73), 25% (18/73), 63% (26/41). High methylation consistencies of p16/shp1 were observed between plasma and FFPE tumor tissues. In plasma and FFPE tumor tissues, there was a higher frequency of methylated p16 in B-NHL patients who had later disease stage, while no similar association was observed in PBLs samples; Higher frequency of methylated p16 was observed in B-NHL patients who had B symptoms and lower platelet count (<100×10⁹/L) in all three samples. Methylated shp1 was frequently detected in patients with high serum LDH level. In summary, DNA methylation in plasma may be promising biomarkers for B-NHL diagnosis, prognosis evaluation, and targeted therapy.