[Clinical Effect of Tyrosine Kinase Inhibitors in the Treatment of P230 Chronic Myeloid Leukemia].

OBJECTIVE: To observe the curative efficacy of tyrosine kinase inhibitors (TKIs) in the treatment of e19a2 transcript (P230) CML chronic phase (CML-CP) patients. METHODS: The clinical data of 11 P230 CML-CP patients were collected from July 2008 to December 2019. Blood routine examination, bone marrow cytology, chromosome, and BCR-ABL qualitative and quantitative tests were performed at initial diagnosis. After TKIs treatment, BCR-ABL (P230)/ABL in peripheral blood was regularly detected to evaluate molecular response by real-time quantitative PCR. RESULTS: There were 11 patients (7 males and 4 females) in chronic phase from 6 domestic hospitals enrolled, their median age was 46 years old (range from 19 to 56 years old). Among 4 patients treated with imatinib (400 mg, qd) firstly, 3 cases switched to nilotinib (400 mg, bid) and 1 case switched to dasatinib (100 mg, qd) due to failure to achieve best molecular response at the landmark time or mutation of ABL kinase. Then major molecular response (MMR) was obtained within 1 year. In addition, 5 patients were treated with nilotinib (300 mg, bid) and 2 patients with dasatinib (100 mg, qd) as first-line treatment, all of them got MMR within 6 months. CONCLUSION: For intolerance or resistance to imatinib, second-generation TKIs can enable P230 CML patients to achieve deeper molecular response, and MMR in a short time.

[Establishing the Ion Torrent PGM Sequencing Methods for the Clinical Diagnosis of MPN Patients].

OBJECTIVE: To investigate the feasibility and relibility of rapidly and accurately acquiring the informations of gene mutations in MPN patients by using self-designed custom MPN mutation-related multipe-PCR primer kit and next generation Ion Torrent PGM sequencing platform. METHODS: The bone marrow samples of 10 MPN patients with JAK2V617F and/or CALR+, Ph- confirmed by sanger sequencing method were collected and were re-detected by using next generation Ion Torrent PGM sequencing method, then the consistence of results of above-mentioned 2 kinds of detection methods was compared. RESULTS: In terms of JAK2V617F, MPL and CALR mutations, the results of Ion Torrent PGM sequencing were complete consistent with results of Sanger sequencing, except 52 bp deletion of CALR gene, which conld not be detected by next generation Ion Torrent PGM sequencing method in all bone marrow samples. CONCLUSION: The detection of multiple gene mutations in MPN patients by Ion Torrent PGM sequencing platform is feasible and can meet the needs of clinical testing. This method can complete detection of all 23 mutetions within 1-2 days, moreover, possesses advantages of high sensitivity, specificity, rapidity, high throughput and low cost.

Correlation between deletion of the CDKN2 gene and tyrosine kinase inhibitor resistance in adult Philadelphia chromosome-positive acute lymphoblastic leukemia.

BACKGROUND: Frequency relapses are common in Philadelphia chromosome-positive (Ph-positive) acute lymphoblastic leukemia (ALL) following tyrosine kinase inhibitors (TKIs). CDKN2A/B is believed to contribute to this chemotherapy resistance. METHODS: To further investigate the association between CDKN2 status and TKI resistance, the prevalence of CDKN2 deletions and its correlation with a variety of clinical features was assessed in 135 Ph-positive ALL patients using interphase fluorescence in situ hybridization (I-FISH). RESULTS: Results showed that no difference occurred between patients with CDKN2 deletion (44/135) and wild-type patients in sex, age, and complete remission (CR) rate following induction chemotherapy combined with tyrosine kinase inhibitors (TKIs). However, CDKN2 deletion carriers demonstrated higher white blood cell (WBC) count, enhanced rates of hepatosplenomegaly (P = 0.006), and upregulation of CD20 expression (P = 0.001). Moreover, deletions of CDKN2 resulted in lower rates of complete molecular response (undetectable BCR/ABL), increased cumulative incidence of relapse, short overall survival (OS), and disease-free survival (DFS) time (P < 0.05) even though these patients received chemotherapy plus TKIs followed by allogenic hematopoietic stem cell transplantation (Allo-HSCT). In the case of 44 patients who presented with CDKN2 deletion, 18 patients were treated with dasatinib treatment, and another 26 patients were treated with imatinib therapy, and our study found that there were no differences associated with OS (P = 0.508) and DFS (P = 0.555) between the two groups. CONCLUSIONS: CDKN2 deletion is frequently acquired during Ph-positive ALL progression and serves as a poor prognostic marker of long-term outcome in Ph-positive ALL patients with CDKN2 deletion even after the second-generation tyrosine kinase inhibitor treatment.

CDKN2 Gene Deletion as Poor Prognosis Predictor Involved in the Progression of Adult B-Lineage Acute Lymphoblastic Leukemia Patients.

Deletion of cyclin-dependent kinase inhibitor 2A/B (CDKN2A/B) is well known in many hematologic malignancies, but only few reports have investigated this deletion effect on clinical prognosis. This study performed analysis of the CDKN2 deletion in 215 adult B- lineage acute lymphoblastic leukemia (B-ALL) patients, and related cytogenetic prognostic factors (BCR/ABL; E2A/PBXl; TEL/AML1; Mixed Lineage Leukemia (MLL) rearrangement; MYC, Immunoglobulin heavy locus (IGH) translocation). The prevalence of CDKN2 deletions in all study populations was 28.4%. There is no difference between patients with CDKN2 deletion and wild-type patients in sex, age, white blood cells (WBC) count, BM blast percentage, extra infiltration and induction complete remission (CR) rate. Analysis in relapse patients revealed that the distribution of CDKN2 deletion is higher in relapse patients (44.6%) than all patients (28.4%, P=0.006). Deletion of CDKN2 was significantly associated with poor outcomes including decreased overall survival (OS) (P<0.001), lower disease free-survival (DFS) (P<0.001), and increased cumulative incidence of relapse (P=0.002); Also, CDKN2 deletion was strongly associated with IGH translocation (P=0.021); and had an adverse effect on patients with BCR-ABL fusion gene or with MLL rearrangement. Patients with CDKN2 gene deletion benefited from allogenic hematopoietic stem cell transplantation (Allo-HSCT). Deletion of CDKN2 gene was commonly observed through leukemia progression and was poor prognostic marker in long-term outcomes.

Prognostic Significance of Monosomal Karyotype in Adult Patients With Acute Myeloid Leukemia Treated With Risk-Adapted Protocols.

BACKGROUND: The monosomal karyotype (MK) is a well-known adverse prognostic factor and has been found to be related to poor outcome in patients with acute myeloid leukemia (AML). However, the outcome in MK-positive AML patients undergoing different therapies has not been well investigated. PATIENTS AND METHODS: We retrospectively analyzed clinical and laboratory features in 225 MK-positive AML patients. Clinical outcome of overall survival (OS) and disease-free survival (DFS) was evaluated in patients according to age group and in patients who received different therapy protocols. RESULTS: The proportion of MK-positive patients increased along with age. Also, patients who were treated with high-dose cytarabine (HD-Ara-C) as consolidation therapy followed by allogeneic hematopoietic stem cell transplantation (allo-HSCT) demonstrated longer OS and DFS compared to allo-HSCT or HD-Ara-C alone. Patients treated with allo-HSCT alone exhibited longer DFS compared to patients treated with HD-Ara-C alone. No difference in OS was discovered between these 2 single protocols. CONCLUSION: MK was associated with a lower complete remission rate. HD-Ara-C therapy followed by allo-HSCT could improve the prognosis of MK-positive AML patients.