Translation initiation plays a critical role in cellular homeostasis, proliferation, differentiation and malignant transformation. Consistently, increasing the abundance of the eIF2·GTP·Met-tRNAi translation initiation complex transforms normal cells and contributes to cancer initiation and the severity of some anemia. The chemical modifiers of the eIF2·GTP·Met-tRNAi ternary complex are therefore invaluable tools for studying its role in the pathobiology of human disorders and for determining if this complex can be pharmacologically targeted for therapeutic purposes. Using a cell based assay, we identified N,N’-diarylureas as novel inhibitors of the ternary complex abundance. Direct functional-genetics and biochemical evidence demonstrated that the N,N’-diarylureas activate heme regulated inhibitor kinase, thereby phosphorylate eIF2α and reduce abundance of the ternary complex. Using tumor cell proliferation in vitro and tumor growth in vivo as paradigms, we demonstrate that N,N’-diarylureas are potent and specific tools for studying the role eIF2·GTP·Met-tRNAi ternary complex in the pathobiology of human disorders.

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The increasing prevalence of childhood obesity in high socio-economic status is associated with health risks. In obese children with family history of obesity and cardiovascular disease or type 2 diabetes mellitus and in obese children who had any feature of metabolic syndrome, frequency of 4G/4G genotype was more than the 4G/5G and 5G/5G genotypes in the PAI-1 gene. These patients can be at increased risk for developing vascular disease. Acanthosis nigricans, high HOMA-IR value, hypertriglyceridemia and high atherogenic index can also reflect the high risk of vascular disease in metabolic syndrome.

Wnt/β-catenin signalling pathway plays important roles in embryonic development and carcinogenesis. Overactivation of the pathway is one of the most common driving forces in major cancers such as colorectal and breast cancers. The downstream effectors of the pathway and its regulation of carcinogenesis and metastasis are still not very well understood. In this study, which was based on two genome-wide transcriptomics screens, we identify MENA (ENAH, Mammalian enabled homologue) as a novel transcriptional target of the Wnt/β-catenin signalling pathway. We show that the expression of MENA is upregulated upon overexpression of degradation-resistant β-catenin. Promoters of all mammalian MENA homologues contain putative binding sites for Tcf4 transcription factor – the primary effector of the Wnt/β-catenin pathway and we demonstrate functionality of these Tcf4-binding sites using luciferase reporter assays and overexpression of β-catenin, Tcf4 and dominant-negative Tcf4. In addition, lithium chloride-mediated inhibition of GSK3β also resulted in increase in MENA mRNA levels. Chromatin immunoprecipitation showed direct interaction between β-catenin and MENA promoter in Huh7 and HEK293 cells and also in mouse brain and liver tissues. Moreover, overexpression of Wnt1 and Wnt3a ligands increased MENA mRNA levels. Additionally, knock-down of MENA ortholog in D. melanogaster eyeful and sensitized eye cancer fly models resulted in increased tumor and metastasis formations. In summary, our study identifies MENA as novel nexus for the Wnt/β-catenin and the Notch signalling cascades.

To investigate the clinical efficacy and safety of the finasteride (5 mg/day) plus flutamide (125 mg/day) combination therapy in unselected women with hirsutism, 44 women were involved in the study. The effects of such combination treatment have not been reported previously. The patients were assigned to 3 treatment groups: 14 patients (group 1) were treated with finasteride (5 mg per day), 16 patients (group 2) were treated with flutamide (125 mg per day), and 14 patients (group 3) were treated with finasteride (5 mg per day) plus flutamide (125 mg per day) for 12 months. Serum FSH, LH, estradiol, total testosterone, free testosterone, androstenedione, DHEAS, and SHBG were obtained. Hirsutism score was measured before and after treatment. Blood chemistry and side effects were evaluated during the study. The reductions in hirsutism score (% of the baseline) at 6 months were as follows: 24% for group 1, 35% for group 2, and 33% for group 3. Combination therapy resulted in (49%) similar improvement to flutamide alone (45%), but significantly (p<0.05) more efficacious improvement in hirsutism when compared to finasteride (32%) after 12 months of treatment. In conclusion, flutamide is more effective than finasteride and the combination of these two drugs is not better than flutamide alone, but better than finasteride in hirsute women.