ABCB1 and BMI1 mRNA expression in patients with chronic myeloid leukemia: impact on imatinib efficacy.

BACKGROUND: ATP-binding cassette transporters are important in the mechanism of multidrug resistance. ABCB1 displays a high affinity for imatinib. BMI1 is a polycomb group protein thought to be overexpressed in leukemic cells. METHODS: This study was conducted to investigate the prognostic value of ABCB1 and BMI1 expressions in chronic myeloid leukemia (CML). Expression levels were measured in 81 patients newly diagnosed with CML and 20 healthy controls by real time reverse transcription- PCR. RESULTS: The ABCB1 expression levels did not differ between patients with CML and controls. Low ABCB1 mRNA levels were observed in patients who achieved an optimal response compared to suboptimal and resistant cases (P=0.005). Non-responders showed the highest ABCB1 levels. ABCB1 expression did not affect the progression-free survival (PFS) of patients. BMI1 expression was higher in patients than that in controls (P=0.001). Patients in advanced phases expressed higher levels of BMI1 than those in the chronic phase (P=0.004). High BMI1 expression was associated with a shorter PFS. CONCLUSION: ABCB1 mRNA expression may serve as a predictor of the optimal response to imatinib treatment in patients with CML. BMI1 expression was higher in the accelerated and blastic crisis phases of CML and associated with a shorter PFS.

The Influence of CYP2C9 and VKORC1 Gene Polymorphisms on the Response to Warfarin in Egyptians.

Warfarin is the most commonly used drug for chronic prevention of thromboembolic events, it also ranks high among drugs that cause serious adverse events. The variability in dose requirements has been attributed to inter-individual differences in medical, personal, and genetic factor. Cytochrome P-450 2C9 is the principle enzyme that terminates the anticoagulant effect of warfarin by catalyzing the conversion of the pharmacologically more potent S-enantiomer to its inactive metabolites. Warfarin exerts its effect by inhibition of vitamin K epoxide reductase. This protein is encoded by vitamin K epoxide reductase complex subunit 1 gene (VKORC1). The current study aimed to investigate the pharmacogenetic effect of CYP2C9 and VKORC1 gene polymorphisms on the patients response to warfarin. One hundred cases starting warfarin treatment and 20 healthy controls were enrolled. The mean daily dose of warfarin was calculated from patient's medical records. For each patient, less than 10 % variability in warfarin dose and a target international normalized ratio (INR) within the therapeutic target range were required for at least 3 months for one of the following indications (deep vein thrombosis, pulmonary embolism, cerebrovascular stroke and myocardial infarction) prior to inclusion in the study. Tetraprimer amplification refractory mutation system PCR was performed to determine CYP2C9*2, CYP2C9*3, and the VKORC1 1639 G > A genetic polymorphisms. Plasma warfarin determination was performed using rapid fluorometric assay. Plasma warfarin concentration ranged from 2.19 to 10.98 µg/ml with a median 3.52 µg/ml. Supratherpeutic INR was observed in 11 % of the cases. Thromboembolic complications occurred in 7 % of the cases and 8 % of cases experienced major bleeding. High maintenance dose (>7 mg/day) was associated with the combined non VKORC1*2 and homozygous wild type CYP2C9 (CYP2C9*1*1) alleles, while low maintenance dose was associated with the Variant (AG + AA)/Wild (*1/*1). (p value <0.001). CYP2C9 variant was a risk factor for supratherapeutic INR in the multivariate logistic regression model. Thromboembolic complication and incidence of supratherapeutic INR were observed in patients carrying combined VKORC1 Variant (AG + AA) and CYP2C9 Variant (*2/*3). Data from our study suggest that together with clinical factors, VKORC1 and CYP2C9 polymorphisms are important contributors to warfarin dosing and may help predict adverse effects in Egyptian patients.

Correction to: The Influence of CYP2C9 and VKORC1 Gene Polymorphisms on the Response to Warfarin in Egyptians.

[This corrects the article DOI: 10.1007/s12288-016-0725-4.].

Prognostic Value of miRNA-155 Expression in B-Cell Non-Hodgkin Lymphoma.

OBJECTIVE: MicroRNA-155 (miRNA-155) resides within the B-cell integration cluster gene on chromosome 21. It can act either as an oncogene or as a tumor-suppressor gene, depending on the cell background in which miRNA-155 is performing its specific target gene controlling function. Therefore, the aim of this study was to investigate miRNA-155 expression in patients with B-cell non-Hodgkin lymphoma (NHL) and its relation to disease prognosis in diffuse large B-cell lymphoma (DLBCL) patients. MATERIALS AND METHODS: Reverse transcription-polymerase chain reaction assay was performed to evaluate the expression levels of miRNA-155 in 84 patients with newly diagnosed B-cell NHL and 15 normal controls. RESULTS: Compared with normal controls, miRNA-155 expression was significantly upregulated in patients. Moreover, higher levels of miRNA-155 were associated with the presence of B symptoms, involvement of extranodal sites, and high Eastern Cooperative Oncology Group (ECOG) score. Higher levels of miRNA-155 in DLBCL were associated with non-germinal B-cell-like type, the presence of B symptoms, involvement of extranodal sites, and higher International Prognostic Index (IPI) and ECOG scores. Only the high IPI score and high miRNA-155 expression indicated a higher risk of lower event-free survival using multivariate Cox regression analysis. Our data demonstrated that the expression of miRNA-155 was upregulated in newly diagnosed B-cell NHL patients. miRNA-155 is expressed at a lower level in GCB-subtype DLBCL. Low IPI score and miRNA-155 expression were predictors of longer event-free survival. CONCLUSION: Despite contradicting literature reports, the current findings suggest the potential value of miRNA-155 as a biomarker of prognosis and monitoring in B-cell NHL, and especially that of the DLBCL type.

The prognostic value of glucocorticoid receptors for adult acute lymphoblastic leukemia.

BACKGROUND: Therapeutic protocols used in adult acute lymphoblastic leukemia (ALL) are widely variable, and glucocorticoids (GCs) are essential components in ALL treatment. Therefore, this study aimed to evaluate the distribution of prominent glucocorticoid receptor (GR) gene polymorphic variants among adult ALL patients. We also investigated the association between GR messenger ribonucleic acid (mRNA) isoform expressions and the response to chemotherapy. METHODS: Fifty-two newly diagnosed Philadelphia-negative adult ALL patients and 30 healthy control subjects were enrolled in this study. Genotyping was carried out using a polymerase chain reaction (PCR)-restriction fragment length polymorphism analysis. GR mRNA isoform expressions were assayed by quantitative real-time PCR. RESULTS: ALL patients in this study had a median age of 34 years (range, 18-75). GRα expression was associated with complete remission (P=0.03), while GRγ mRNA expression was significantly higher in GC resistant patients (P=0.032) and in non-responders (P=0.019). However, there were no significant associations with GC resistance. The BclI polymorphic variant of the GR gene was the most frequent in adult ALL patients and was not associated with the GC response. Both higher GRα expression and lower GRγ expression were associated with achievement of complete remission, while higher GRγ expression was associated with GC-resistance. CONCLUSION: Our data suggest that the level of GR isoform expression may be useful in predicting GC response, achievement of complete remission, and better event-free survival in ALL patients. However, further evaluation with a larger cohort of patients is warranted.

XPD gene polymorphisms and the effects of induction chemotherapy in cytogenetically normal de novo acute myeloid leukemia patients.

BACKGROUND: Cytogenetically normal acute myeloid leukemia (AML) represents nearly half of newly diagnosed de novo AML cases. XPD is one of the DNA repair proteins, whose genetic polymorphisms are thought to affect their function as regards response to chemotherapeutic drugs and chemotherapy-induced toxicities. SUBJECTS AND METHODS: We investigated the XPD Asp312Asn and Lys751Gln polymorphisms by polymerase chain reaction-restriction fragment length polymorphism in 51 newly diagnosed cytogenetically normal de novo AML patients. The response to the standard induction chemotherapy protocol and chemotherapy-induced toxicities were monitored. RESULTS: The XPD Asp312Asn GG genotype was the most frequent (57%) followed by the GA variant (37%), and the AA variant was the least frequent (6%). As regards the XPD Lys751Gln polymorphism, the AA genotype was the most frequent (49%), followed by the AC (39%) and CC (12%) variants. These variants were not associated with age, sex, FAB subtype, CNS infiltration, chemotherapy-induced hepatotoxicity, nephrotoxicity, or metabolic toxicity. The XPD Lys751Gln CC polymorphic variant was associated with chemotherapy-induced cardiotoxicity and lower chance to achieve response to induction chemotherapy. CONCLUSION: XPD Lys751Gln and not Asp312Asn polymorphism was associated with chemotherapy-induced cardiotoxicity and response to induction chemotherapy in newly diagnosed cytogenetically normal AML patients. Pretreatment assay of XPD Lys751Gln may help to anticipate cardiotoxicity in those at risk. Moreover, it may be considered a prognostic marker in AML cases. However, further large scale research is needed to verify its usefulness.

Do baseline Cereblon gene expression and IL-6 receptor expression determine the response to thalidomide-dexamethasone treatment in multiple myeloma patients?

Immunomodulatory drugs (IMiDs) are key components of treatment for hematologic malignancies, especially multiple myeloma (MM). Cereblon (CRBN) expression was described to be essential for the activity of thalidomide. Furthermore, IMiD binding to CRBN is cytotoxic to multiple myeloma cells and absence of CRBN confers IMiDs resistance. Interleukin-6 (IL-6) is a potent pleiotropic cytokine that regulates plasma cell (PC) growth via the IL-6 receptor (IL-6R). IL-6/IL-6R autocrine activity is implicated in the development and progression of cancers including cervical cancer, prostate cancer, and multiple myeloma. The aim of the study was to evaluate CRBN and IL-6R expressions and their impact on clinical efficacy of dexamethasone-thalidomide therapy in multiple myeloma (MM) patients, in addition to their association with other clinical and prognostic parameters. Forty-six newly diagnosed MM patients were enrolled in the study. We measured CRBN expression prior to therapy initiation by real-time polymerase chain reaction in 46 bone marrow (BM) aspiration samples of patients and controls. In addition, IL-6R expression was evaluated on BM biopsies of patients and controls by immunohistochemistry (IHC). Twenty-eight males (60.9%) and 18 females (39.1%) were enrolled. The mean age was 65.11 ± 7.3 yr (range 39-77 yr). Median CRBN expression in 46 BM samples of MM patients was significantly higher than in controls (P < 0.001). Among established prognostic parameters, international staging system (ISS), serum beta-2-microglobulin (B2M), and serum albumin correlated reversely with CRBN expression. IL-6R expression was significantly higher in patients than in controls. IL-6R expression was significantly associated with response to treatment (P < 0.001), B2M (P = 0.032), and ISS (P = 0.028). Strong intensity expression was associated with low CRBN expression (P = 0.001).In conclusion, CRBN expression may provide a biomarker to predict response to IMiD in patients with MM and its high expression can serve as a marker of good prognosis. Strong IL-6R expression is associated with poor response to therapy in multiple myeloma patients and may be used as a prognostic marker.

Assessing DcR3 expression in relation to survivin and other prognostic factors in B cell non-Hodgkin's lymphoma.

UNLABELLED: The soluble decoy receptor 3 (DcR3) is a member of the tumor necrosis factor receptor superfamily whose overexpression has been observed in several human malignancies. Survivin is one of the inhibitors of apoptosis proteins that are thought to play an important role in the pathogenesis of malignancies. We aimed to evaluate the expression of DcR3 in relation to survivin in B cell non-Hodgkin`s lymphoma (NHL) and then we focused on patients with diffuse large B cell non-Hodgkin's lymphoma (DLBCL) (50 cases) and correlated DcR3 expression with survivin expression and other prognostic parameters. Fifteen subjects with reactive lymphoid hyperplasia were included as controls. The expression of DcR3 and survivin were analyzed by immunohistochemistry on formalin-fixed paraffin-embedded lymph node sections from 80 cases of B cell NHL and 15 controls. Bone marrow biopsy sections of patients were also immunostained with the previous markers. RESULTS: DcR3 expression was found in 32.5% of B cell NHL patients versus 6.7% of controls (p <0.001) and was associated with the aggressive/highly aggressive subtypes. DcR3 was strongly expressed in 30% of DLBCL patients, where it was associated with survivin expression, high international prognostic index (IPI), the presence of extra nodal disease, ECOG performance status >1, reduced remission rates and shorter event-free survival. The expression of survivin was 40% in B cell NHL patients versus 13.3% in the control group (p <0.001). The expression of survivin in aggressive/highly aggressive B cell NHL was significantly higher than that in indolent B cell NHL. Survivin expression has been detected in 44% of the DLBCL patients and was associated with their clinical stage and shorter event-free survival (p = 0.026). Bone marrow biopsy sections from DLBCL patients showed significant DcR3 and survivin over expressions in sections with infiltration by lymphoma cells than sections with no infiltration. CONCLUSION: DcR3 expression was associated with other prognostic factors including survivin, reduced remission rates, and shorter event-free survival. Survivin is closely related to aggressive/highly aggressive subtypes of B cell NHL and is associated with shorter event-free survival. Both DcR3 and survivin expressions on bone marrow sections can be of help in diagnosing bone marrow infiltration.

Do SLCO1B3 (T334G) and CYP3A5*3 polymorphisms affect response in Egyptian chronic myeloid leukemia patients receiving imatinib therapy?

BACKGROUND: Imatinib has so far been the first-choice treatment in chronic myeloid leukemia (CML) with excellent results. However, only a proportion of patients achieve major molecular response. Hence, the need to find whether there are some factors that affect the response to treatment is essential. This study aimed to investigate the allele and genotype frequencies of single nucleotide polymorphisms (SNPs) of SLCO1B3 (T334G) and CYP3A5*3 in CML patients undergoing imatinib treatment and to determine whether SNPs of these two genes could predict the response of imatinib therapy in CML patients. SUBJECTS AND METHODS: We investigated SLCO1B3 (T334G) and CYP3A5*3 polymorphisms by Polymerase Chain Reaction-restriction fragment length polymorphism in 86 Philadelphia positive newly diagnosed Egyptian CML patients (78 patients in chronic phase and 8 patients in accelerated phase). All patients received imatinib therapy and were followed for at least one and half years. The response to imatinib therapy was evaluated by recording the hematological response, cytogenetic response, and molecular response according to the European Leukemia Net criteria. RESULTS: This study included 86 Philadelphia positive newly diagnosed CML patients, 78 in the early chronic phase and 8 in the accelerated phase. In the chronic phase patients, no association between SLCO1B3 (T334G) exon 3 polymorphism and response to imatinib therapy was detected (P = 0.938) while CYP3A5*3 gene polymorphism was associated with inferior outcome (P < 0.001). In the group of accelerated phase patients, the SLCO1B3 polymorphic variants (TG) and (GG) were detected equally with none of the patients in this group having the homozygous wild form (TT). The homozygous state for the CYP3A5*3 allele was the most frequent (50%) and the homozygous state for the CYP3A5*1 allele was the least frequent (12.5%) in this group. CONCLUSION: CYP3A5*3 polymorphism was associated with imatinib efficacy while the SNP SLCO1B3 (T334G) was not associated with the response to imatinib treatment in Egyptian patients with CML in chronic phase. These results prompt us to explore the effect of CYP3A5*3 in CML patients taking imatinib in a larger scale study.