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Abnormal apoptosis is one of the hallmarks of cancers including acute myeloid leukemia (AML), as it plays a pivotal role in precisely maintaining self-renewal, proliferation, and differentiation properties of hematopoietic stem cells (HSCs). Caspase9 (CASP9), an initiator caspase activated by mitochondrial-mediated apoptotic pathway (intrinsic pathway), triggers cascade of effector caspases and executes apoptosis. Functional SNPs in CASP9 might influence the gene expression leading to altered apoptosis which confer the risk to AML. To test this hypothesis, we have analyzed four CASP9 gene polymorphisms [CASP9 - 1263A > G (rs4645978), CASP9 - 712C > T (rs4645981), CASP9 - 293_275del CGTGAGGTC AGTGCGGGGA (-293del) (rs4645982), and CASP9 Ex5 + 32G > A (rs1052576)] in 180 AML cases and 304 age- and sex-matched healthy controls. We performed various statistical analyses to determine the potential interactions between these SNPs and AML. The study revealed that presence of G allele at CASP9 - 1263 position elevates the risk of AML 1.53-fold and CT/TT genotype at CASP9 - 712 position by 2.60-fold under dominant model of inheritance. Two CASP9 haplotypes, G-del(+)-C-A and G-del(+)-T-A, were found to be significantly associated with increased AML risk by 2.19- (95 % confidence interval (CI), 1.09-4.39; p = 0.028) and 11.75-fold (95 % CI, 1.01-136.57; p = 0.05), respectively. Further, multidimensionality reduction (MDR) analysis had revealed single locus CASP9 - 712C > T SNP and four loci CASP9 - 1263A > G, CASP9 - 293del, CASP9 - 712C > T, and CASP9 Ex5 + 32G > A SNPs as highest predicting models for AML development. Our results revealed a significant association of two SNPs in CASP9 (-1263A > G and -712C > T) and two haplotypes of the four SNP combinations with AML susceptibility.

Chronic myeloid leukemia (CML) is a monoclonal myeloproliferative disorder of hematopoietic stem cells (HSCs), characterized by reciprocal translocation, leading to the formation of BCR-ABL oncogene with constitutive tyrosine kinase (TK) activity. This oncogene is known to deregulate different downstream pathways which ultimately lead to cell proliferation, defective DNA repair, and inhibition of apoptosis. Fas (Fas cell surface death receptor) is a member of tumor necrosis factor (TNF) superfamily which interacts with its ligand, FasL, to initiate apoptosis. Promoter polymorphisms in Fas-FasL genes are known to influence the apoptotic signaling. Hence, the present study has been aimed to find out the association of the promoter polymorphisms in Fas and FasL genes with the development and progression of CML. Blood samples from 772 subjects (386 controls and 386 cases) were collected and genotyped for Fas-FasL gene polymorphisms through PCR-RFLP method. The association between SNPs and clinical outcome was analyzed using statistical softwares like SPSS version 20, SNPSTATs, and Haploview 2.1. The study revealed a significant association of Fas -670 G>A and FasL -844 T>C polymorphisms with the development of CML while Fas -670 AG was associated with accelerated phase. Combined risk analysis by taking the risk genotypes in cases and controls revealed a significant increase in CML risk with increase in number of risk genotypes (one risk genotype-OR 1.99 (1.44-2.76), p < 0.0001; two risk genotypes-OR 3.33 (1.91-5.81), p < 0.0001). Kaplan-Meier survival analysis of Fas -670 A>G and FasL -844 T>C showed reduced event-free survival in patients carrying the variant genotypes, Fas -670 GG, 32.363 ± 6.33, and FasL -844 CC, 33.489 ± 5.83, respectively. Our findings revealed a significant association of Fas -670 GG, FasL -844 TC, and CC genotypes with increased risk of CML.

Extremophilic microorganisms often produce novel bioactive compounds to survive under harsh environmental conditions. Exopolysaccharides (EPSs), a constitutive part of bacterial biofilm, are functional biopolymers that act as a protecting sheath to the extremophilic bacteria and are of high industrial value. In this study, we elucidate a new EPS produced by thermophilic Bacillus haynesii CamB6 from a slightly acidic (pH 5.82) Campanario hot spring (56.4 °C) located in the Central Andean Mountains of Chile. Physicochemical properties of the EPS were characterized by different techniques: Scanning electron microscopy- energy dispersive X-ray spectroscopy (SEM-EDS), Atomic Force Microscopy (AFM), High-Performance Liquid Chromatography (HPLC), Gel permeation chromatography (GPC), Fourier Transform Infrared Spectroscopy (FTIR), 1D and 2D Nuclear Magnetic Resonance (NMR), and Thermogravimetric analysis (TGA). The EPS demonstrated amorphous surface roughness composed of evenly distributed macromolecular lumps. GPC and HPLC analysis showed that the EPS is a low molecular weight heteropolymer composed of mannose (66%), glucose (20%), and galactose (14%). FTIR analysis demonstrated the polysaccharide nature (–OH groups, Acetyl groups, and pyranosic ring structure) and the presence of different glycosidic linkages among sugar residues, which was further confirmed by NMR spectroscopic analyses. Moreover, D-mannose α-(1→2) and α-(1→4) linkages prevail in the CamB6 EPS structure. TGA revealed the high thermal stability (240 °C) of the polysaccharide. The functional properties of the EPS were evaluated for food industry applications, specifically as an antioxidant and for its emulsification, water-holding (WHC), oil-holding (OHC), and flocculation capacities. The results suggest that the study EPS can be a useful additive for the food-processing industry.