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Biomedical subjects

K A Al-Hussein

Publications and source records attributed to K A Al-Hussein.

3 recordsLinked to original sources

Curcumin induces apoptosis via inhibition of PI3'-kinase/AKT pathway in acute T cell leukemias.

Curcumin has been shown to possess variety of biological functions including anti-tumor activity. The mechanism by which curcumin inhibit cell proliferation remains poorly understood. In the present report, we investigated the effect of curcumin on the activation of apoptotic pathway in T-cell acute lymphoblastic leukemia (T-ALL) malignant cells. Our data demonstrate that curcumin causes dose dependent suppression of proliferation in several T cell lines. Curcumin treatment causes the de-phosphorylation/inactivation of constitutively active AKT, FOXO transcription factor and GSK3. Curcumin also induces release of cytochrome c accompanied by activation of caspase-3 and PARP cleavage. In addition, zVAD-fmk, a universal inhibitor of caspases, prevents caspase-3 activation and abrogates cell death induced by curcumin treatment. Finally, treatment of T-ALL cells with curcumin down-regulated the expression of inhibitor of apoptosis protein (IAPs). Taken together, our finding suggest that curcumin suppresses constitutively activated targets of PI3'-kinase (AKT, FOXO and GSK3) in T cells leading to the inhibition of proliferation and induction of caspase-dependent apoptosis.

Apoptosis↗

HLA-DPB1*0401 is associated with dominant protection against type 1 diabetes in the general Saudi population and in subjects with a high-risk DR/DQ haplotype.

The human leukocyte antigen (HLA) class II DQB1*0201/0202-DRB1*04 genotype has been identified as predisposing to type 1 diabetes [insulin-dependent diabetes mellitus (IDDM)] in the Saudi Arabian population (P = 0.0002; odds ratio = 0.67; 95% confidence interval = 0.009-0.381). In this study, we searched for a factor at the DPB1 locus by analysing DPB1 polymorphism using sequence-based typing in 86 Saudi IDDM patients and control subjects, all carrying the HLA-DRB1*04/DQB1*02 haplotype or the known susceptibility allele DQB1*0201/0202. Significant protection was conferred by DPB1*0401, which was observed in 17 of 50 control subjects (55%) and 2 of 36 IDDM patients (5%) with the DQB1*0201/0202 allele (P = 0.0012; odds ratio = 8.75; confidence interval = 1.72-59.70). Our data showing a high frequency of the DPB1*0401 allele even in the presence of the predisposing DQB1*02 allele in healthy subjects may indicate a protective effect of this combination of HLA alleles against type 1 diabetes. This finding supports the hypothesis that protective HLA class II genes can override the risk conferred by HLA-DQ susceptibility alleles. Further studies using larger cohorts of control subjects and patients should be undertaken to confirm this observation.

Diabetes Mellitus, Type 1↗

HLA class II sequence-based typing in normal Saudi individuals.

We have adopted a system that combines low resolution PCR-SSP followed by sequence-based typing (SBT) to analyze HLA-DRB1, -DPB1 and -DQB1 alleles in the Saudi population. The SBT method was used to identify HLA class II alleles in Saudis for the first time. Nineteen HLA-DRB1 alleles in currently recognized subtypes of the DRB locus were detected. DR1 and DR9 were not encountered. SBT did not detect diversity within the DR7 and DR10 alleles. Sixteen HLA-DQB1 and 10 HLA-DPB1 alleles were identified. This study represents the first molecular report on the HLA class II allele frequency in the population of Saudi Arabia.

Arabs↗