Predictive value of tyrosine phosphatase receptor gamma for the response to treatment tyrosine kinase inhibitors in chronic myeloid leukemia patients

• Published in: Scientific reports 2021-04, Vol.11 (1), p.8833-8833, Article 8833
• Main Authors: Ismail, Mohamed A., Vezzalini, Marzia, Morsi, Hisham, Abujaber, Ahmad, Al Sayab, Ali, Siveen, Kodappully, Yassin, Mohamed A., Monne, Maria, Samara, Muthanna, Cook, Richard, Sorio, Claudio, Modjtahedi, Helmout, Al-Dewik, Nader I.
• Format: Article
• Language: English
• Subjects: 692/4028; 692/420; 692/699/67; 692/699/67/1059; 692/699/67/1059/2326; 692/699/67/1059/602; 692/699/67/395; Adult; Antineoplastic Agents - therapeutic use; Biomarkers, Tumor - metabolism; Case-Control Studies; Chronic myeloid leukemia; Diagnosis; Down-regulation; Female; Flow Cytometry; Fusion Proteins, bcr-abl - genetics; Humanities and Social Sciences; Humans; Imatinib; Leukemia; Leukemia, Myelogenous, Chronic, BCR-ABL Positive - drug therapy; Leukemia, Myelogenous, Chronic, BCR-ABL Positive - pathology; Leukocytes (neutrophilic); Lymphocytes - drug effects; Male; Middle Aged; Monoclonal antibodies; Monocytes; multidisciplinary; Myeloid leukemia; Peripheral blood; Phosphatase; Protein Kinase Inhibitors - therapeutic use; Protein-tyrosine-phosphatase; Proteins; Receptor-Like Protein Tyrosine Phosphatases, Class 5 - genetics; Receptor-Like Protein Tyrosine Phosphatases, Class 5 - metabolism; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger - genetics; Science; Science (multidisciplinary); Transcription; Treatment Outcome; Tumor suppressor genes; Tyrosine kinase inhibitors
• ISSN: 2045-2322; 2045-2322
• DOI: 10.1038/s41598-021-86875-y

Protein tyrosine phosphatase receptor gamma ( PTPRG ) is a member of the receptor-like family protein tyrosine phosphatases and acts as a tumor suppressor gene in different neoplasms. Recent studies reported the down-regulation of PTPRG expression levels in Chronic Myeloid Leukemia disease (CML). In addition, the BCR-ABL1 transcript level is currently a key predictive biomarker of CML response to treatment with Tyrosine Kinase Inhibitors (TKIs). The aim of this study was to employ flow cytometry to monitor the changes in the expression level of PTPRG in the white blood cells (WBCs) of CML patients at the time of diagnosis and following treatment with TKIs. WBCs from peripheral blood of 21 CML patients were extracted at diagnosis and during follow up along with seven healthy individuals. The PTPRG expression level was determined at protein and mRNA levels by both flow cytometry with monoclonal antibody (TPγ B9-2) and RT-qPCR, and BCR-ABL1 transcript by RT-qPCR, respectively. PTPRG expression was found to be lower in the neutrophils and monocytes of CML patients at time of diagnosis compared to healthy individuals. Treatment with TKIs nilotinib and Imatinib Mesylate restored the expression of PTPRG in the WBCs of CML patients to levels observed in healthy controls. Moreover, restoration levels were greatest in optimal responders and occurred earlier with nilotinib compared to imatinib. Our results support the measurement of PTPRG expression level in the WBCs of CML patients by flow cytometry as a monitoring tool for the response to treatment with TKIs in CML patients.