OCA2 rs4778137 polymorphism predicts survival of breast cancer patients receiving neoadjuvant chemotherapy.

BACKGROUND: Genome-wide association study (GWAS) studies have showed that single nucleotide polymorphisms (SNPs) in OCA2 gene were associated with the survival of breast cancer patients treated with adjuvant chemotherapy. To further explain the association between OCA2 SNPs and breast cancer survival, we investigated the predictive value of rs4778137 located in OCA2 in local advanced breast cancer patients receiving neoadjuvant chemotherapy. PATIENTS AND METHODS: A case-cohort with 150 breast cancer patients was performed to evaluate the effects of the OCA2 rs4778137 on breast cancer survival. The association between rs4778137 genotypes and pathological complete response (pCR, defined that the postoperative pathology indicating no residual invasive breast cancer in the breast or the axillary lymph node) were analyzed. Logistic regression analysis was performed to identify the independent predictors of pCR. Survival was assessed by Kaplan-Meier method and Cox regression analysis according to the rs4778137 genotypes. RESULTS: The differences between pCR and the rs4778137 genotypes were statistically significant (p < 0.05). The patients with genotype GG harbored a better disease-free survival (HR: 2.358, p = 0.000) and overall survival (HR: 1.578, p = 0.008) than the patients with genotype CC in rs4778137. The further Univariate and Multivariate survival analysis revealed that SNP rs4778137 was an independent predictive factor of disease-free survival (p = 0.000/p = 0.001) and overall survival (p = 0.006/p = 0.045). CONCLUSION: The OCA2 rs4778137 may be a predictor for the clinical response and survival in local advanced breast cancer patients who received neoadjuvant chemotherapy.

[Effects of stable isotope labeled internal standard on determination of ivabradine and N-demethylivabradine in human plasma].

This study aims to develop a liquid chromatography with tandem mass spectrometry (LC-MS/MS) method for the simultaneous determination of ivabradine and N-demethylivabradine in human plasma, and investigate effects of stable isotope labeled (SIL) internal standard (IS) on ivabradine. The analytes and IS were extracted from plasma by protein precipitation with acetonitrile, and chromatographied on a Capcell PAK C18 (100 mm x 4.6 mm, 5 µm) column using a mobile phase of methanol and 5 mmol x L(-1) ammonium acetate. Multiple reaction monitoring with electrospray ionization (ESI) was used in the positive mode for mass spectrometric detection. The effect of ivabradine isotope peak [M+H+3] + on IS and the effect of SIL IS purity on ivabradine were evaluated. An appropriate concentration of SIL IS was chosen to permit method selectivity and linearity of the assay over the required range. The standard curves were demonstrated to be linear in the range of 0.100 to 60.0 ng x mL(-1) for ivabradine, and 0.050 0 to 20.0 ng x mL(-1) for N-demethylivabradine. The intra and inter day precision and accuracy were within the acceptable limits for all concentrations. Besides, the interaction between IS and ivabradine did not impact the determination of analytes. This method was successfully applied to a pharmacokinetic study of hydrogen sulfate ivabradine sustained release tablets on Chinese healthy volunteers.

Association of plasma visfatin levels with inflammation, atherosclerosis and acute coronary syndromes (ACS) in humans.

OBJECTIVES: Visfatin is a new cytokine that act as an insulin analogue on the insulin receptor and may link obesity and insulin resistance. It was recently shown that visfatin plays a role in plaque destabilization. However, the role of visfatin in atherosclerosis remains to be elucidated. We sought to assess whether plasma visfatin level is independently associated with inflammation, atherosclerosis and acute coronary syndromes (ACS). DESIGN AND PATIENTS: Two hundred and fifty-three patients undergoing coronary angiography were divided into three subgroups: chronic coronary artery disease (CAD) (n = 102), ACS (n = 100) and control patients (n = 51). The plasma samples were thawed and analysed for circulating visfatin, monocyte chemoattractant protein 1 (MCP-1), interleukin-6 (IL-6), high sensitivity C-reactive protein (hs-CRP). The association of visfatin with risk factors, inflammation, atherosclerosis, and ACS was determined. RESULTS: Plasma visfatin levels were significantly higher in chronic CAD and ACS compared with control patients. Multiple regression analysis demonstrated that plasma visfatin levels correlated with inflammatory factors and were associated with chronic CAD (odds ratio [OR][95% confidence interval], for second, third and fourth quartiles were 1.74 [0.96-2.69], 1.54 [0.85-2.28] and 1.84 [0.98-2.87], respectively) and ACS (ORs for second, third and fourth quartiles were 2.56 [1.57-3.34], 4.61 [1.94-10.96] and 6.52 [2.34-18.12], respectively) following adjustment for established risk factors and other inflammatory factors. CONCLUSIONS: Plasma visfatin levels are significantly associated with CAD, particularly ACS, independent of well-known CAD risk factors.