Genetic and epigenetic regulation of the organic cation transporter 3, SLC22A3

Human organic cation transporter 3 (OCT3 and SLC22A3) mediates the uptake of many important endogenous amines and basic drugs in a variety of tissues. OCT3 is identified as one of the important risk loci for prostate cancer, and is markedly underexpressed in aggressive prostate cancers. The goal of this study was to identify genetic and epigenetic factors in the promoter region that influence the expression level of OCT3. Haplotypes that contained the common variants, g.-81G>delGA (rs60515630) (minor allele frequency 11.5% in African American) and g.-2G>A (rs555754) (minor allele frequency>30% in all ethnic groups) showed significant increases in luciferase reporter activities and exhibited stronger transcription factor-binding affinity than the haplotypes that contained the major alleles. Consistent with the reporter assays, OCT3 messenger RNA expression levels were significantly higher in Asian (P<0.001) and Caucasian (P<0.05) liver samples from individuals who were homozygous for g.-2A/A in comparison with those homozygous for the g.-2G/G allele. Studies revealed that the methylation level in the basal promoter region of OCT3 was associated with OCT3 expression level and tumorigenesis capability in various prostate cancer cell lines. The methylation level of the OCT3 promoter was higher in 62% of prostate tumor samples compared with matched normal samples. Our studies demonstrate that genetic polymorphisms in the proximal promoter region of OCT3 alter the transcription rate of the gene and may be associated with altered expression levels of OCT3 in human liver. Aberrant methylation contributes to the reduced expression of OCT3 in prostate cancer.

Statin treatment use in diabetic patients with breast cancer: A potential C-reactive protein mediated benefit

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Background: Statin treatment has not yet been evaluated in relation to breast cancer (BC) prognosis in diabetes mellitus (DM) patients. Reported decreased survival following BC in women with metabolic syndrome, led us to investigate whether specific statin therapy may lead to improved BC survival. Reported associations between elevated C-reactive protein (CRP) levels at the time of diagnosis with worse cancer prognosis, and CRP-lowering properties of statin treatment in non-cancer patients, led us to investigate whether statin use is associated with lower CRP levels at the time of BC diagnosis and with improved BC outcomes.

Methods: All DM patients newly diagnosed with BC between 2003 and 2007 (Roswell Park Cancer Institute) were retrospectively reviewed (n = 225). BC pathology, outcomes, existing comorbidities and drug therapy were documented. Follow up began at BC diagnosis and ended with first confirmed recurrence and/or death, or last date of follow-up. Hazard ratios (HR) and 95% confidence intervals (CI)s representing the association between statins, BC and a defined event were computed with Cox proportional hazards model. CRP plasma levels were determined by enzyme-linked immunosorbent assay in specimens donated at the time of BC diagnosis. A total of 98 study patients, DM+BC, and their matched controls, BC only (n = 196) were analyzed.

Results: After a median follow up of 30 months, patients receiving statins for cholesterol management were found to have better disease-free survival (HR 0.27, 95% CI: 0.10, 0.71, X2 = 7.31, p = 0.06), and lower overall mortality (HR 0.23, 95% CI: 0.08, 0.66, X2 = 7.80, p = 0.05) compared to patients not receiving any cholesterol management medication. CRP levels have ranged between 0.2 and 21 mg/L and clinically relevant levels ( > 3mg/L) were noted in the study group.

Conclusions: This study explored for the first time the association between statin therapy and BC prognosis in DM. We observed improved outcomes in statin-treated patients. While we currently analyze statin therapy in relationship with baseline CRP levels and BC prognosis, our existing findings suggest that statins have the potential to improve BC outcomes potentially through lowering overall inflammation.

Exercise in, and adaptations to a cold environment have no effect on SIgA

AIM

The authors hypothesized that inconsistent SIgA response to exercise is caused by the different adaptative status of subjects to a cold environment. The purposes of the study were to examine whether moderate-intense exercise in a cold environment decreases SIgA and whether adaptation to a cold environment has any effect on SIgA.

METHODS

Young male skaters, short track (N=9) and inline (N=10), participated in this study. All subjects cycled for 60 min at 65% VO(2max) in cold (ambient temperature: 5 +or - 1 degrees Celsius, relative humidity 41 + or - 9%) and thermoneutral (ambient temperature: 21 + or - 1 degrees Celsius, relative humidity 35 + or - 5%) conditions. Saliva samples were collected as follows: before and after 1hour of environmental exposure; immediately, 30-min, 60-min and 120-min after the exercise.

RESULTS AND CONCLUSIONS

Salivary SIgA and saliva flow rate decreased after the exercise in both groups only in thermoneutral conditions. The SIgA secretion rate did not decrease after moderate-high intensity exercise in a cold environment, and the SIgA response to exercise was not affected by the different adaptative status of subjects to the cold environment.

Phase I/II study of docetaxel and 153Sm for castrate metastatic prostate cancer (CMPC): Summary of dose-escalation cohorts and first report on the expansion cohort

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Background: We previously reported (ASCO 2008) that full doses of docetaxel (Tax) and Sm can be repetitively delivered safely using a schedule of q 3 week (wk) Tax and q 6–9 wk Sm. Here we summarize the dose-escalation cohorts and safety/efficacy data from the expansion cohort of 24 pts. Methods: Cohorts of 3–6 pts with CPMC were defined by: 65, 70, 75, 75, 75 mg/m2 of Tax and Sam 0.5, 0.5, 0.5, 0.75, 1 mCi/kg. Each cycle was 6 wks. The expansion cohort used 75 mg/m2 Tax (q 3 wk) and 1 mCi/kg Sm (q 9 wk). Pts with an ANC of grade 0–1 and platelet count of > 100,000/mm3 at the end of cycle 1 received additional cycles until progression or toxicity. Results: 52 pts have been treated. 28 pts were taxane naïve, 11 received previous taxanes but were not refractory, and 13 were taxane refractory. As anticipated, side effects were primarily hematologic. However, the leading cause for treatment termination was disease progression, involving 16/52 (31%) pts, rather than toxicity. 12/52 (23%) pts came off for thrombocytopenia, and 2/52 (4%) pts experienced neutropenic fever. Cohort 3 tolerated the highest cumulative dose and total number of doses of docetaxel (mean of 8 doses, range 4–12; mean total dose 600 mg/m2, range 300–900 mg/m2). Cohort 5 tolerated the highest exposure to Sm (mean of 3 doses, range 1–5). 50 pts are evaluable for response; 22 (44%) achieved a ≥ 50% decline in PSA. 50% of the taxane naïve patients achieved a significant PSA decline, as did 55% of the taxane exposed, and 23% of the taxane refractory pts. Mean time to progression in the taxane naïve, treated, and refractory groups were: 7.5 (range 1.4–22.6), 5.8 (range 0.7–13.7), and 4.3 (range 0.7–11.2) months. Conclusions: This regimen is safe and appears to be active both in taxane naïve and taxane refractory patients, as reflected by favorable toxicity profiles, and rates of significant PSA declines and times to progression. The optimal phase II dose may differ by the population treated. For studies involving taxane naïve patients, the regimen of cohort 3 maximizes docetaxel exposure; for studies of taxane refractory patients, cohort 5 maximizes Sm exposure. Support: EUSA, NIH CA102544.

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Identification of human metapneumovirus-induced gene networks in airway epithelial cells by microarray analysis

Human metapneumovirus (hMPV) is a major cause of lower respiratory tract infections in infants, elderly and immunocompromised patients. Little is known about the response to hMPV infection of airway epithelial cells, which play a pivotal role in initiating and shaping innate and adaptive immune responses. In this study, we analyzed the transcriptional profiles of airway epithelial cells infected with hMPV using high-density oligonucleotide microarrays. Of the 47,400 transcripts and variants represented on the Affimetrix GeneChip Human Genome HG-U133 plus 2 array, 1601 genes were significantly altered following hMPV infection. Altered genes were then assigned to functional categories and mapped to signaling pathways. Many up-regulated genes are involved in the initiation of pro-inflammatory and antiviral immune responses, including chemokines, cytokines, type I interferon and interferon-inducible proteins. Other important functional classes up-regulated by hMPV infection include cellular signaling, gene transcription and apoptosis. Notably, genes associated with antioxidant and membrane transport activity, several metabolic pathways and cell proliferation were down-regulated in response to hMPV infection. Real-time PCR and Western blot assays were used to confirm the expression of genes related to several of these functional groups. The overall result of this study provides novel information on host gene expression upon infection with hMPV and also serves as a foundation for future investigations of genes and pathways involved in the pathogenesis of this important viral infection. Furthermore, it can facilitate a comparative analysis of other paramyxoviral infections to determine the transcriptional changes that are conserved versus the one that are specific to individual pathogens.