The single nucleotide polymorphism and haplotype analysis of MDR1 in Chinese diffuse large B cell lymphoma patients

The impact of matched and mismatched donor-recipient genotypes for MDR1 polymorphisms (G2677TA, C1236T and C3435T) on the outcomes of patients after allogeneic haematopoietic stem cell transplantation

In this study, we investigated whether matched and mismatched multidrug resistance gene (MDR1) genotypes (G2677TA, C1236T and C3435T) were associated with prognosis in patients after allogeneic haematopoietic stem cell transplantation (allo-HSCT). One hundred patients after transplantation and their donors were enrolled. Matched MDR1 G2677TA donor-recipient was associated with an increased risk of non-relapse mortality (NRM) (29.5% vs. 6.2%, p = 0.002), poor overall survival (OS) (51.7% vs. 63.8%, p = 0.024) and disease-free survival (DFS) (38.6% vs. 67%, p = 0.005). There were no differences in OS, DFS or NRM between MDR1 C1236T- and C3435T-matched and -mismatched groups. Subgroup analysis suggested that within the matched MDR1 G2677TA group, male gender, haematopoietic cell transplantation-specific comorbidity index ≥1, serum creatinine >137.2 μmol/L and post-transplantation thrombocytopenia were associated with poor survival. Our results demonstrated that patients receiving matched MDR1 G2677TA allo-HSCT experienced a poorer prognosis compared with the mismatched group. The potential mechanism may involve increased expression of P-glycoprotein, leading to decreased accumulation of antimicrobial agents and ultimately contributing to the progression of inflammation. This identification of MDR1 G2677TA genotype compatibility holds promise as a valuable molecular tool for selecting donors for allo-HSCT.

Clinical relevance of multi-drug resistance gene C3435T polymorphism in diffuse large B-cell lymphoma in Xinjiang

To explore the relationship between C3435T polymorphism of multi-drug resistance gene (MDR1) gene and susceptibility, clinicopathological characteristics, curative effect and hematological toxicity of diffuse large B-cell lymphoma (DLBCL) in XinJiang.The peripheral venous blood samples of 54 patients with DLBCL and 60 healthy controls were collected. The alleles and genotypes of MDR1 gene C3435T were detected by DNA direct extraction with PCR technique, and the frequency of C3435T allele and genotypes were detected by the chi-square test. The relationship between the allele and genotype distribution of C3435T locus and the susceptibility, clinicopathological characteristics, curative effect and hematological toxicity of DLBCL were analyzed.1 the frequency of CT heterozygote and CC homozygote mutation was significantly higher in the case group (46.3% in CT genotype and 42.6% in CC genotype) compared to the control group (P < 0.05). The frequency of CC genotype mutation in the case group was 42.6%, which was significantly higher than that in the control group (P < 0.05, OR 3.209, 95% CI: 1.288-7.997). 2 the genotypes of C3435T locus of MDR1 gene were distributed in age, sex, nationality, pathological characteristics, clinical-stage, IPI index, B symptoms, infection with EB virus, clinicopathological characteristics and clinical efficacy of hepatitis B in patients with DLBCL. There was no significant difference in myelosuppression (P > 0.05).The homozygous mutation genotype of CC is the risk genotype of DLBCL. The alleles and genotypes are not associated with the clinicopathological characteristics, efficacy and myelosuppression toxicity of DLBCL.

An Engineered Fusion Protein Anti-CD19(Fab)-LDM Effectively Inhibits ADR-Resistant B Cell Lymphoma

The 5-year survival rate of patients with B cell lymphoma is about 50% after initial diagnosis, mainly because of resistance to chemotherapy. Hence, it is necessary to understand the mechanism of chemo-resistance and to explore novel methods to circumvent multidrug resistance. Previously, we showed that an engineered cytotoxic fusion protein anti-CD19(Fab)-LDM (lidamycin), can induce apoptosis of B-lymphoma cells. Herein, we successfully established an adriamycin (ADR)-resistant B cell lymphoma cell line BJAB/ADR. The mRNA and protein level of ATP-binding cassette subfamily B member 1 (ABCB1) were significantly overexpressed in BJAB/ADR cells. Increased efflux function of ABCB1 was observed by analyzing intracellular accumulation and efflux of Rhodamine 123. The efflux of Rhodamine 123 could be significantly ameliorated by verapamil. Treatment with anti-CD19(Fab)-LDM at different concentrations induced cytotoxic response of BJAB/ADR cells similar to that of the sensitive cells. In vivo studies showed that anti-CD19(Fab)-LDM had better antitumor effect in BJAB and BJAB/ADR cell lymphoma xenografts compared with ADR or LDM treatment alone. Taken together, anti-CD19(Fab)-LDM can effectively inhibit the growth of BJAB/ADR cells both in vitro and in vivo. Anti-CD19(Fab)-LDM could be a promising molecule for the treatment of drug resistant cancers.

Haplotype Analysis of MDR1 and Risk for Cervical Cancer in Northeastern Thailand

Objective: The aim of this study was to investigate the association between genotype and haplotype of MDR1 (C1236T, G2677T/A and C3435T) and the risk for cervical cancer in Northeastern Thai women. Methods: An age-matched case-control study involving squamous cell cervical cancer (SCCA) patients (n=204) and healthy controls (n=204) was enrolled for MDR1 genotyping by real-time PCR method. Results: The genotype distribution of MDR1 in both patients and controls was not significantly different (p>0.05). The haplotype analysis showed that T-T-T was the most common haplotype in this population. Significantly increased risk of cervical cancer was observed in carriers of T-T-C and C-G-T haplotypes with ORs of 1.86 (95%CI=1.02-3.39, p=0.0416) and 2.00 (95%CI=1.18-3.40, p=0.0140), respectively. Analysis of 2677-3435 haplotype showed increased risk for cervical cancer in G-T (OR=1.55; 95% CI=1.12-2.13, p=0.0432) and T-C (OR=1.91; 95%CI=1.05-3.47, p=0.0325). Conclusion: The results provide evidence that haplotype of MDR1 may be an important risk factor for cervical cancer development in Northeastern Thai women.

Genetic Variants in the Transcriptional Regulatory Region of the ALOX5AP gene and Susceptibility to Ischemic Stroke in Chinese Populations

No coding sequence variants of the ALOX5AP gene that lead to amino acid substitutions have been identified. A two-stage study design was used to explore the relationship between variants in the transcriptional regulatory region of ALOX5AP gene and ischemic stroke (IS) risk in Chinese populations. IS was determined using CT and/or MRI. First, 18 SNPs, located in the upstream promoter region of ALOX5AP gene, were genotyped in 200 IS patients and 200 controls. And one potential associated SNP (rs17222919) was identified (P = 0.005,OR = 0.623, 95% CI: 0.448~0.866). Next, another independent case-control cohort comprising 810 IS patients and 825 matched controls was recruited to investigate the role of rs17222919, rs9579646 polymorphisms and their haplotypes in IS risk. The G allele frequency of rs17222919 in the IS group was significantly lower than that in control group (P = 0.007, OR = 0.792, 95% CI: 0.669~0.937). T-A and G-A haplotypes were associated with IS (P = 0.001,OR = 1.282, 95% CI:1.100~1.495; P = 0.0001, OR = 0.712, 95% CI: 0.598~0.848; respectively). Our study providesevidence that rs17222919 is a potential genetic protective factor against IS. Furthermore, the T-A haplotype is a risk factor and the G-A haplotype is a protective factor against IS in Chinese population.