Cytochrome P450 2W1 (CYP2W1) – ready for use as the biomarker and drug target for cancer?

1.?This article aims to evaluate the potentials of using cytochrome P450 2W1 (CYP2W1) as a biomarker and a drug target of cancer because of its characteristic cancer-specific expression.

2.?Discrepant findings comparing the expression levels of CYP2W1 in cancer and non-cancer samples were reported. In general, the expression followed a developmental pattern. The demethylation status of CpG island and the expression levels of CYP2W1 genes was positively correlated.

3.?CYP2W1 was able to activate several procarcinogens, anticancer pro-drugs and to metabolise many endogenous substances including fatty acids and lysophospholipids.

4.?CYP2W1 expression level was suggested to serve as an independent prognostic biomarker in colorectal cancer and hepatocellular carcinoma. The correlation of genetic polymorphisms of CYP2W1 and cancer risk was uncertain.

5.?Further characterisation of CYP2W1 structure is suggested to link to its functions. More studies are warranted to reveal the true status and the regulation of CYP2W1 expression across normal and cancer tissues. Catalytic activity of CYP2W1 should be tested on a wider spectrum of endogenous and exogenous substances before its use as the drug target. Larger size of clinical samples can be included to verify the potential of CYP2W1 as the prognostic or cancer risk biomarker.     

Does computer-assisted surgical navigation total knee arthroplasty reduce venous thromboembolism compared with conventional total knee arthroplasty?

INTRODUCTION: The study aims to show that total knee arthroplasty using computer-assisted surgical navigation without intramedullary rodding is safer than conventional intramedullary techniques in preventing venous thromboembolism. METHODS: 30 patients were grouped into groups of 10. Groups A and B had conventional intramedullary rodding of the femur and/or tibia. Group C had no rodding of the femur and tibia using computer-assisted surgical navigation. The degree, duration and size of the embolic shower were captured by a transoesophageal echocardiography probe. The echogenic emboli were graded according to the Mayo Clinic score. Haemodynamic parameters such as pulse oximetry oxygen saturation, end-tidal carbon dioxide, heart rate and mean arterial pressure were also recorded. RESULTS: There was a significant difference in the size of the emboli and the Mayo Clinic score when comparing the groups with intramedullary rodding and those without. There was also a significant difference in the pulse oximetry oxygen saturation and heart rate when the group without intramedullary rodding was compared with groups with rodding. CONCLUSION: Surgical navigation total knee arthroplasty may be safer than conventional total knee replacement with intramedullary rodding in preventing venous thromboembolism.     

GnRH agonist and GnRH antagonist in intracytoplasmic injection cycles

The long agonistic protocol for controlled ovarian hyperstimulation (COH) is effective and used most often, thus is considered the gold standard. Therefore any new regimen has to be compared in its results with those obtained with the long protocol. This report compares the efficacy of GnRH agonist and antagonist in a retrospective study of IVF/ICSI carried out in a tertiary teaching hospital from 2003 to 2006. Only the first COH cycle followed by IVF-ICSI from 200 couples (agonist = 120 and antagonist = 80) were analysed. The end points studied included the number of oocytes recovered, number of mature (MII) oocytes, fertilization, cleavage, morphology based embryo quality, pregnancy rate, quantity and cost of gonadotrophin. The average age of female subjects was 35.1 +/- 4.7 years with 50% being 35 years and above. Major infertility factors were tubal blockage, male factor and endometriosis altogether comprising 68%. GnRH agonist and antagonist cycle parameters were comparable except lesser amount of gonadotrophin was used with lower resultant costs (both p < 0.0005) in antagonistic regime. Antagonist regime produce somewhat more good quality embryos (p = 0.065), an insignificant difference. A clinical pregnancy rate per embryo transfer of 16.3% in agonist and 20.6% in antagonist regime was achieved respectively. In conclusion, GnRH antagonist protocol produced a COH response, embryonic development and pregnancy rates on par to GnRH agonist regime. Moreover GnRH antagonist protocol required a shorter stimulation period plus fewer complications. Hence GnRH antagonist regime provided means for a friendlier, convenient and cost effective protocol for patients.     

Single-nucleotide polymorphisms near the microsatellite D17S1303 and the development of hypertension in a 6-year longitudinal study

This study examined the association of tagging single-nucleotide polymorphisms (SNPs) in the 130 kb region surrounding the microsatellite D17S1303 on chromosome 17p12 with the development of hypertension after 6 years in a cohort of 232 Hong Kong Chinese adults. Four SNPs (rs9899362, rs10491093, rs11658572 and rs9913883) were associated with the development of hypertension (P<0.05), but these associations require confirmation in future studies. Nevertheless, our study provides further evidence for the presence of an unidentified gene or a regulatory element predisposing to hypertension in a region approximately 24 kb downstream of D17S1303.     

Toxicity of single-walled carbon nanotubes

Carbon nanotubes (CNTs) are an important class of nanomaterials, which have numerous novel properties that make them useful in technology and industry. Generally, there are two types of CNTs: single-walled nanotubes (SWNTs) and multi-walled nanotubes. SWNTs, in particular, possess unique electrical, mechanical, and thermal properties, allowing for a wide range of applications in various fields, including the electronic, computer, aerospace, and biomedical industries. However, the use of SWNTs has come under scrutiny, not only due to their peculiar nanotoxicological profile, but also due to the forecasted increase in SWNT production in the near future. As such, the risk of human exposure is likely to be increased substantially. Yet, our understanding of the toxicological risk of SWNTs in human biology remains limited. This review seeks to examine representative data on the nanotoxicity of SWNTs by first considering how SWNTs are absorbed, distributed, accumulated and excreted in a biological system, and how SWNTs induce organ-specific toxicity in the body. The contradictory findings of numerous studies with regards to the potential hazards of SWNT exposure are discussed in this review. The possible mechanisms and molecular pathways associated with SWNT nanotoxicity in target organs and specific cell types are presented. We hope that this review will stimulate further research into the fundamental aspects of CNTs, especially the biological interactions which arise due to the unique intrinsic characteristics of CNTs.