Evaluating frequency of PML-RARA mutations and conferring resistance to arsenic trioxide-based therapy in relapsed acute promyelocytic leukemia patients.

The aim of the study is to better understand the mechanism of relapse and acquired clinical resistance to arsenic trioxide (ATO) and/or all-trans retinoic acid (ATRA). Thirty relapsed acute promyelocytic leukemia (APL) patients were followed. Fifteen patients experienced two or more relapses; nine patients had clinical resistance to ATO-based therapy. The frequency and clinical significance of promyelocytic leukemia (PML)-retinoic acid receptor alpha (RARA) mutational status using Sanger sequencing were evaluated. Overall, eight different types of mutations in the RARA region (V218D, R272Q, T278A, T291I, N299D, R294W, A300G, and L220_F228delinsP) were identified in 11 patients. Eight missense mutations (L211P, C213R, S214L, A216V, L217F, D219H, S221G, and D241G) were found in the PML portion of PML-RARA in 14 patients, with A216V as the predominant mutation. Eight patients were found to harbor both PML and RARA mutations over the course of the disease. The PML-region mutations were associated with response to ATO-based therapy (P < 0.0001), number of relapses (P = 0.001), and early relapse (P = 0.013). Notably, one case sampled at nine different time points showed alternating clonal dominance over the course of treatment. This study demonstrated frequent mutations of PML-RARA and supported a clonal selection model in relation to APL relapse and ATO resistance.

Platelet to white blood cell ratio was an independent prognostic predictor in acute myeloid leukemia.

BACKGROUND: Recently, platelet to white blood cell ratio (PWR) was reported as an independent prognostic predictor in acute promyelocytic leukemia. Acute myeloid leukemia (AML) often presents with abnormal platelet counts and white blood cell counts (WBC) at disease diagnosis. However, the clinical impact of PWR on cytogenetically normal AML (CN-AML) is still unclear. Therefore, we evaluate its prognostic impact on CN-AML patients. METHODS: We recorded the clinical information at the time of disease diagnosis, and calculated the ratio of platelet counts to WBC in 338 patients with CN-AML. To assess the prognostic value of PWR, we divided patients into low, intermediate and high group based on the values of PWR. The independent prognostic value of PWR was investigated in the context of the well-established predictors including white blood cell counts, age, and genes of NPM1, FLT3-ITD, CEBPA, and DNMT3A mutations. Receiver operating characteristic (ROC) curve was used to assess the performance of its prognostic prediction. RESULTS: Higher PWR have the higher levels of platelet counts, but lower levels of white blood cell counts, percentage of bone marrow blasts, FLT3-ITD and NPM1 mutations. The performance of survival prediction was comparable between PWR alone and combined molecular biomarkers. Moreover, PWR had the additional prognostic information to the molecular biomarkers. Finally, PWR was associated with favorable overall survival and event free survival in CN-AML patients independent of genetic subtypes and clinical parameters. CONCLUSION: We found PWR was an independent prognostic predictor in CN-AML.

Triptolide overcomes dexamethasone resistance and enhanced PS-341-induced apoptosis via PI3k/Akt/NF-kappaB pathways in human multiple myeloma cells.

Human multiple myeloma is a presently incurable hematological malignancy and novel biologically based therapies are urgently needed. Triptolide (TPL) is a purified diterpenod isolated from the Chinese herb, Tripterygium wilfordii Hook. F that has shown antitumor activities in various cancer cell types. But its activity in Dex-resistant multiple myeloma cell lines and the main upstream signaling pathway has not been reported. Here we show that TPL induces apoptosis in dexamethasone-sensitive (MM.1S) and dexamethasone-resistant (MM.1R) cells, most importantly its main upstream signaling pathway is through the PI3k/Akt/NF-kappaB pathway and is also associated with MAPK pathway, via mitochondrial apoptotic signaling and is also associated with the caspase and Bcl-2 family members. Moreover, TPL was able to enhance the activities of dexamethasone or bortezomib/PS-341 in multiple myeloma cell lines. Collectively, these findings provide the framework for a clinical evaluation of TPL, either alone or in combination with dexamethasone or bortezomib/PS-341, to overcome drug resistance and improve outcome for patients with this universally fatal hematological malignancy.

Prognostic impact of MYH9 expression on patients with acute myeloid leukemia.

MYH9 expression has previously been demonstrated as an independent predictor of clinical outcome in solid tumors. However, the prognostic relevance of MYH9 expression in acute myeloid leukemia is still unclear. Here, we found high MYH9 expressers were seen more frequently in females and more frequently in M4 morphology. We also found high MYH9 expressers had lower percentage of bone marrow blasts. In addition, overexpression of MYH9 was associated with an inferior overall survival. Notably, distinct microRNA signatures were seen in high MYH9 expressers. These results were also validated in an independent cohort of AML patients using the published data. In conclusion, gene of MYH9 expression might serve as a reliable predictor for overall survival in AML patients.

Prognostic significance of huntingtin interacting protein 1 expression on patients with acute myeloid leukemia.

Huntingtin interacting protein 1 (HIP1) is an endocytic protein which is overexpressed in a variety of human cancers and involved in cancer-causing translocation in leukemia. However, the prognostic impact of HIP1 expression on AML remains unclear. In this study, quantification of HIP1 transcript by real-time quantitative PCR in bone marrow blasts was performed in 270 AML patients. As a result, high HIP1 expression was seen more frequently in older patients, M4/M5 morphology and genes of NPM1 and DNMT3A mutations, and underrepresented in favorable karyotype subgroups and CEBPA double allele mutations in our AML patients. We also found high HIP1 expressers showed lower levels of hemoglobin. In addition, overexpression of HIP1 was associated with an inferior overall survival. The prognostic value of HIP1 expression was validated in patients from an independent TCGA cohort. Notably, up-regulation of miR-16, miR-15a, miR-28 and miR-660 were seen in high HIP1 expressers from the two independent cohorts. In vitro, interfereing of HIP1 expression by siRNA suppressed the proliferation of leukemic cells, and downregulation of these miRNAs were seen in THP-1 and Kasumi cell lines after silencing HIP1 expression. In conclusion, the HIP1 gene expression might serve as a reliable predictor for overall survival in AML patients.

[Karyotype analysis of 283 cases of myelodysplastic syndrome].

OBJECTIVE: To explore the implication of karyotype analysis in diagnosis and prognosis of myelodysplastic syndrome (MDS). METHODS: The chromosomes were prepared with direct method, brief culture of cells and R-banding techniques, and then the karyotypic analysis was performed. RESULT: Seventy-seven out of 283 patients (27.21%) had karyotypic abnormalities, including the numeral abnormalities of chromosomes and structural alterations. The most common chromosomal aberrations were +8, -20/20q-, -Y, translocation, -7/7q-, +9, -5/5q-. The rate of abnormal karyotype in refractory anemia with erythroblasts (RAEB) and refractory anemia erythroblasts-transformation (RAEB-t) was much higher than in refractory anemia (RA). Patients with abnormal karyotype or higher IPSS scores had a higher risk of transformation into acute leukemia than patients with normal karyotype or lower IPSS scores (P<0.05). CONCLUSION: MDS is a highly heterogenous disorder and karyotype analysis is helpful for its diagnosis and prognosis estimation.

Prognostic factors of patients with newly diagnosed acute promyelocytic leukemia treated with arsenic trioxide-based frontline therapy.

Prognostic factors for patients with acute promyelocytic leukemia (APL) treated in the context of arsenic trioxide (ATO)-based frontline regimes have not been established clearly. We retrospectively analyzed the clinical features, immunophenotypes, Fms-like tyrosine kinase-3 internal tandem duplication (FLT3-ITD), and outcomes of 184 consecutive newly diagnosed APL patients treated by intravenous ATO-based therapy. The median age was 40 years (14-77 years). The early death rate was 4.9% (9/184 patients). With a median follow-up time of 36 months (9-74 months), the 3-year relapse-free survival (RFS) and overall survival (OS) were 93.3% and 92.2%, respectively. Interestingly, there was no meaningful association between 3-year RFS and initial white blood cell count, FLT3-ITD status, or type of PML-RARA isoforms. In multivariable analysis, the CD56 expression was the only independent risk factor in terms of RFS (hazard ratio, 4.70; P=0.005). These results suggested that ATO-based therapy may ameliorate the unfavorable influence of previously known high-risk features; moreover, CD56 expression remains to be a potentially unfavorable prognostic factor in APL patients.