Pharmacogenetics of induction therapy-related toxicities in childhood acute lymphoblastic leukemia patients treated with UKALL 2003 protocol.

Chemotherapy related toxicities have been the major factor limiting the success of acute lymphoblastic leukemia (ALL) induction therapy. Several factors, including the pharmacogenetics of asparaginase and anthracyclines, could contribute to difference in treatment outcome in ALL. We investigated the significance of variations in genes involved in hepatic and cardiac toxicity in acute lymphoblastic leukemia (ALL). Genotyping of SOD2 (rs4880), PNPL3 (rs738409) and ABCC1 (rs4148350), CBR1 (rs9024) and ABCG2 (rs2231142) was performed by Tetra-ARMS PCR-based technique to evaluate the genotype-phenotype correlation. Our results showed only minor allele G of SOD2 rs4880 increase the risk of hepatic toxicity [OR 2.63 (1.42-4.84), P = < 0.05] while minor alleles of other SNPs showed protective impact. However, the genetic contrast analysis showed a recessive form of SOD2 rs4880 [OR 7.82 (3.86-15.85), P = < 0.05] and PNPLA3 I148M [OR 5.82 (3.43-9.87), P = < 0.05] variants whereas dominant genotype of ABCC1 rs4148350 [OR 2.52 (1.55-4.10), P = < 0.05] significantly predisposes hepatotoxicity. Furthermore, heterozygous form of ABCG2 rs2231142 [OR 5.25 (1.84-14.95), P = < 0.05] and recessive genotype of 3'UTR variant CBR1 rs9024 [OR 2.31 (1.31-4.07), P = < 0.05] were strongly associated with cardiotoxicity. The information obtained from these genetic variations could offer biomarkers for individualization of therapeutic intervention in ALL.

Genetic Contribution to Congenital Heart Disease (CHD).

Congenital heart defects (CHD) are the most common congenital problems in neonates. The basis for CHD is multifactorial, involving genetic and environmental components. The elucidation of genetic components remains difficult because it is a genetically heterogeneous disease. Currently, the major identified genetic causes include chromosomal abnormalities, large subchromosomal deletions/duplications, and point mutations. However, much more remains to be unraveled. An important insight from the research on the genetics of CHD is that any change at the genetic level that alters the dosage of genes required in any process during heart development results in a developmental defect. The use of conventional gene identification (linkage analysis and direct targeted sequencing) methods followed by the rapid advancements in high-throughput technologies (copy number variant platforms, SNP arrays, and next-generation sequencing) has identified an extensive list of genetic causes. However, the most common presentation of CHD is in the form of sporadic cases. Therefore, it is important to identify their underlying genetic cause. In this review, we revisit the causal genetic factors of CHD and discuss the clinical implications of research in the field.

Genetic risk score (GRS) constructed from polymorphisms in the PON1, IL-6, ITGB3, and ALDH2 genes is associated with the risk of coronary artery disease in Pakistani subjects.

BACKGROUND: Coronary artery disease (CAD) is a major killer in today's world. Pakistan is also affected by this non-communicable disease like other countries. It is a multifactorial disease and is influenced by many gene-gene and gene-environment interactions. METHODS: A total of 623 (219 controls, 404 cases) Pakistani subjects were genotyped for four SNPs, rs662 (PON1), rs5918 (ITGB3), rs671 (ALDH2), rs1800795 (IL-6) by PCR-RFLP. Various anthropometric parameters were noted and serum lipid profile was measured using commercially available kits. Statistical analysis was done by SPSS version 22. A Genetic Risk Score (GRS) was calculated from individual SNPs. The association of the SNPs and the GRS with CAD was checked using logistic regression. RESULTS: The results showed that the risk allele frequencies of all variants were higher in the cases than the controls, however the difference was not statistically significant association (p > 0.0125). The mean GRS in the controls was 3.99 ± 1.42 and in cases, it was 4.29 ± 1.39, the difference between the groups was significant (p = 0.0109). logistic regression of individual SNPs and GRS with the CAD showed that independent SNPs were not significantly associated with the CAD however, the GRS had a strong association (p = 1.4 × 10- 4). The subjects were divided into three groups based on GRS (Gp 1 with GRS 0-2, Gp 2 with GRS 3-5 and Gp 3 with GRS 6-8). The analysis of the effect of the individual SNPs and GRS groups on different lipid profile parameters revealed no significant association of any of the tested SNPs with any lipid parameter, however, the GRS groups showed marginally significant for TC and highly significant association for TG, LDL-c and HDL-c. CONCLUSION: In conclusion, use of a GRS can provide better information than individual SNPs. The larger the number of the SNPs included in the analysis, the better would be the risk prediction.

Biowaiver studies of newly optimized meloxicam tablets.

In this research work biowaiver studies of newly developed and optimized Meloxicam 7.5mg and 15mg water dispersible formulations were carried out at different dissolution media i.e. 0.1N HCl, phosphate buffer pH 4.5, pH 6.8, and pH 7.5 at 50 rpm. For this purpose reference (MA9 and MB9) and tests (MA2, MA4, MA6, MA7 and MA8 (15 mg) and MB2, MB4, MB6, MB7and MB8 (7.5 mg) formulations were compared. In vitro patterns were analyzed by using model-independent and model-dependent methods. Results indicated that all formulation at pH 0.1N HCl and phosphate buffer pH 4.5 followed Weibull model, while at pH 6.8 and pH 7.5 all formulations followed Hixson-Crowell model. Similarly results of model independent methods demonstrated that all the reference formulations were found to be similar with the tests formulations. Results indicated that Biowaiver could be granted to all the optimized water dispersible meloxicam formulations of both batches, so waiver for bioequivalence study can be allowed.

GWAS implicated risk variants in different genes contribute additively to increase the risk of coronary artery disease (CAD) in the Pakistani subjects.

BACKGROUND: Coronary artery disease (CAD) remains the single most important cause of mortality worldwide. Many candidate and GWAS genetic variants have been identified in the recent years. In the current study, we selected six SNPs from various genes that have originally been identified in GWAS studies and examined the association of SNPs individually and as a genetic risk score (GRS) with CAD and blood lipid levels in the Pakistani subjects. METHODS: Six hundred twenty-four (404 cases and 219 controls) subjects were genotyped for variants rs10757274 in CDKN2A gene, rs17465637 in MIA3 gene, rs7025486 in DAB2IP gene, rs17228212 in SMAD3 gene, rs981887 in MRAS gene and rs1746048 in CXCL12 gene, by TaqMan and KASPar allele discrimination techniques. Serum lipid parameters were measured using commercially available kits. Statistical analyses were done using SPSS version 22. RESULTS: Individually, the single SNPs were not associated with CAD (p < 0.05). However, the combined GRS of 6 SNPs was significantly higher in cases than controls (4.89 ± 0.11 vs 4.58 ± 0.08, p = 0.024). Among blood lipids, GRS showed significant positive association with serum triglycerides levels (p = 0.022). CONCLUSION: The GRS was quantitatively associated with CAD risk and showed association with serum triglycerides levels, suggesting that the mechanism of these variants is likely to be in part at least through creating an atherogenic lipid profile in subjects carrying high numbers of risk alleles.

Common variants in the genes of triglyceride and HDL-C metabolism lack association with coronary artery disease in the Pakistani subjects.

BACKGROUND: Serum Triglyceride (TG) and High Density Lipoprotein (HDL-C) levels are modifiable coronary artery disease (CAD) risk factors. Polymorphisms in the genes regulating TG and HDL-C levels contribute to the development of CAD. The objective of the current study was to investigate the effect of four such single nucleotide polymorphism (SNPs) in the genes for Lipoprotein Lipase (LPL) (rs328, rs1801177), Apolipoprotein A5 (APOA5) (rs66279) and Cholesteryl ester transfer protein (CETP) (rs708272) on HDL-C and TG levels and to examine the association of these SNPs with CAD risk. METHODS: A total of 640 subjects (415 cases, 225 controls) were enrolled in the study. The SNPs were genotyped by KASPar allelic discrimination technique. Serum HDL-C and TG were determined by spectrophotometric methods. RESULTS: The population under study was in Hardy Weinberg equilibrium and minor allele of SNP rs1801177 was completely absent in the studied subjects. The SNPs were association with TG and HDL-C levels was checked through regression analysis. For rs328, the effect size of each risk allele on TG and HDL-C (mmol/l) was 0.16(0.08) and -0.11(0.05) respectively. Similarly, the effect size of rs662799 for TG and HDL-C was 0.12(0.06) and -0.13(0.0.3) and that of rs708272 was 0.08(0.04) and 0.1(0.03) respectively. The risk allele frequencies of the SNPs were higher in cases than controls, but the difference was not significant (p > 0.05) and SNPs were not associated with CAD risk (p > 0.05). The combined gene score of four SNPs significantly raised TG and lowered HDL-C but did not increase CAD risk. CONCLUSION: The studied SNPs were associated with TG and HDL-C levels, but not with CAD in Pakistani population under study.

rs3751812, a common variant in fat mass and obesity-associated (FTO) gene, is associated with serum high- and low-density lipoprotein cholesterol in Pakistani individuals.

OBJECTIVES: The aim of the present study was to investigate the effect of a common variant of the fat mass and obesity associated (FTO) gene, rs3751812 in obese Pakistani individuals, compare this effect with nonobese controls of the same ethnicity, and then correlate it with serum lipid profile and anthropometric parameters. METHODS: We genotyped 475 samples using TaqMan allelic discrimination assay. Serum total cholesterol, triacylglycerols, and high- (HDL-C) and low-density lipoprotein cholesterol (LDL-C) concentrations were measured. Statistical analysis was done by SPSS version 22 and the results were analyzed for any significant associations. RESULTS: Results demonstrated that the variant is significantly associated with obesity in Pakistan. The study found, for the first time, that the variant has a significant effect on lowering HDL-C and increasing LDL-C. Among anthropometric measures, the variant showed significant association with body mass index and weight. CONCLUSION: The study concludes that the FTO variant is consistently associated with obesity in the Pakistani population and its association with anthropometric and lipid parameters show that it may mediate its role by altering fat deposition and disturbing serum lipid profile. However, future studies with larger sample size are needed to validate the results of the present study.

Association of the leptin receptor Gln223 Arg polymorphism with lipid profile in obese Pakistani subjects.

OBJECTIVE: Leptin receptor gene (LEPR) encodes a receptor for leptin hormone expressed in hypothalamus and single nucleotide polymorphisms in LEPR may have a considerable effect on obesity phenotype. The aim of this study was to investigate an extensively studied LEPR polymorphism Gln223 Arg in a Pakistani study group and its association patterns with different serum biochemical parameters. METHODS: The study included 250 obese and 225 nonobese subjects. Gln223 Arg polymorphism was genotyped by polymerase chain reaction restriction fragment-length polymorphism. Anthropometric parameters and plasma glucose, total cholesterol, triacylglycerols, high density lipoprotein cholesterol, low density lipoprotein cholesterol, leptin, and insulin were measured. RESULTS: The Gln223 Arg polymorphism was found to be significantly associated with body mass index, systolic and diastolic blood pressure, and weight only in obese subjects, and with all lipid parameters in both obese and nonobese subjects when Gln/Gln or Gln/Arg genotypes were compared with Arg/Arg genotype. CONCLUSIONS: The LEPR Gln223 is associated with obesity, lipid parameters, and plasma glucose in all subjects, with weight, body mass index, and systolic and diastolic blood pressure only in obese subjects, but showed no association with leptin, insulin, and HOMA-IR in a Pakistani study group.

Changes in retinal nerve fibre layer, optic nerve head morphology, and visual field after acute primary angle closure.

AIMS/PURPOSE: To determine and correlate the long-term changes in retinal nerve fibre layer (RNFL) thickness, optic nerve head (ONH) morphology, and visual fields after a single episode of acute primary angle closure (APAC). METHODS: This was a cross-sectional comparative study of patients at National University Hospital (Singapore) from 2000 to 2006 after an episode of unilateral APAC. The peripapillary and macular RNFL were measured using Stratus optical coherence tomography (OCT) and ONH configuration was assessed using Heidelberg Retina Tomography (HRT)-III. Humphrey perimetry was also performed, and the presence of disc pallor was noted. APAC eyes were compared with fellow eyes as matched controls. RESULTS: Twenty-five patients were assessed at a median of 33 months (range, 11-85 months) after APAC. OCT showed that there was a reduction in the peripapillary and outer macular RNFL thickness in APAC eyes compared with controls. Humphrey perimetry revealed significantly reduced mean deviation (P=0.006) and increased pattern standard deviation (P=0.045) in APAC eyes compared with controls. HRT-III showed no difference in mean rim area, rim volume, or cup-disc ratio between APAC eyes and controls. Disc pallor was present in nine APAC eyes (36%) but was absent in fellow eyes (P=0.002), and was associated with peripapillary RNFL thinning, visual field loss, and an increased interval between the onset of symptoms and normalization of intraocular pressure (P=0.023). CONCLUSION: APAC results in peripapillary and outer macular RNFL loss, visual field defects, and optic disc pallor, even in cases in which the ONH configuration remains unchanged.

Joint salvage for pathologic fracture of giant cell tumor of the lower extremity.

Pathologic fracture through giant cell tumor is thought to be associated with higher rates of recurrence and poor functional outcome. We compared patients with and without pathologic fracture through giant cell tumor of weightbearing long bones. We retrospectively reviewed 139 patients with giant cell tumor of weightbearing long bones with (n = 43) and without (n = 96) pathologic fracture at presentation; the two groups had similar demographics. Joint salvage was successful in 84% of the fracture group and 96% of the nonfracture group. Five-year recurrence-free survival rates were comparable between the two groups (82.6% [95% confidence interval, 69.1-95.9%] in the fracture group and 77.9% [95% confidence interval, 67.7-88.1%] in the non-fracture group). There was a trend toward lower 5-year metastatic-free survival in the fracture group (94.7% [95% confidence interval, 87.3-100%]) than in the nonfracture group (97.3% [95% confidence interval, 93.5-100%]). Functional outcome was good and similar in the two groups. Arthrofibrosis was more common in the group with pathologic fracture. Joint salvage for patients with pathologic fractures through giant cell tumor of weightbearing bones is a reasonable option with functional outcomes and recurrence rates comparable to those of patients without fracture.

Measurement of the visual contribution to postural steadiness from the COP movement: methodology and reliability.

We studied the reliability of different measures of the visual contribution to postural steadiness by recording the postural sway during standing with eyes open (EO) or eyes closed (EC). The COP trajectory was recorded in 21 subjects aged 42-61 standing on a firm or foam support. The improvement of postural steadiness due to vision was measured with a higher reliability (i.e. lower intra- and inter-subject variabilities) with the sway velocity V, than with the position RMS. Due to the increase of the variability of V and RMS with their own mean values, we quantified the visual contribution to posture by the stabilization ratio (SR), based on a logarithm transform of V or RMS. As compared to the Romberg quotient (EC/EO), SR improved the reliability of the measurement of the visual contribution to posture within individuals, across subjects, and even across different studies in the literature. Our method led to decrease the inter-subject coefficient of variation of this measurement to about 25%, using a foam support. It leads to a similar accuracy in binocular and monocular vision, and it also applies to the quantification of other non-visual sensory contributions to posture.