Statins: a role in breast cancer therapy?

Statin drugs have been used for more than two decades to treat hypercholesterolemia and as cardio-preventive drugs, resulting in a marked decrease in cardiovascular morbidity and mortality worldwide. Statins halt hepatic cholesterol biosynthesis by inhibiting the rate-limiting enzyme in the mevalonate pathway, hydroxymethylglutaryl-coenzyme A reductase (HMGCR). The mevalonate pathway regulates a host of biochemical processes in addition to cholesterol production. Attenuation of these pathways is likely responsible for the myriad benefits of statin therapy beyond cholesterol reduction - the so-called pleiotropic effects of statins. Chief amongst these purported effects is anti-cancer activity. A considerable body of preclinical, epidemiologic and clinical evidence shows that statins impair proliferation of breast cancer cells and reduce the risk of breast cancer recurrence. Potential mechanisms for this effect have been explored in laboratory models, but remain poorly understood and require further investigation. The number of clinical trials assessing the putative clinical benefit of statins in breast cancer is increasing. Currently, a total of 30 breast cancer/statin trials are listed at the global trial identifier website clinicaltrials.gov. Given the compelling evidence from performed trials in a variety of clinical settings, there have been calls for a clinical trial of statins in the adjuvant breast cancer setting. It would be imperative for such a trial to incorporate tumour biomarkers predictive of statin response in its design and analysis plan. Ongoing translational clinical trials aimed at biomarker discovery will help identify, which breast cancer patients are most likely to benefit from adjuvant statin therapy, and will add valuable clinical knowledge to the field.

Association between use of phthalate-containing medication and semen quality among men in couples referred for assisted reproduction.

STUDY QUESTION: Does phthalate exposure from prescription drugs affect semen quality? SUMMARY ANSWER: Exposure to phthalate-containing drugs is associated with poor semen quality. WHAT IS KNOWN ALREADY: Phthalates and their metabolites have been shown to disrupt the hormone signalling in animal studies. One study has shown associations between medicinal phthalate exposure and poor semen quality, suggesting similar effects in humans. STUDY DESIGN, SIZE, DURATION: We included 18 515 males with poor semen quality (cases) and 31 063 males with normal semen quality (controls) registered in the Danish IVF Registry from 2006 to 2016. PARTICIPANTS/MATERIALS, SETTING, METHODS: Exposure to phthalate-containing drugs was assessed from the Danish Register of Medicinal Product Statistics. Outcome measures were obtained at the first contact with the fertility clinic, and categorized according to the International Classification of Diseases (ICD-10). The association between current use of phthalate-containing medications <90 days prior to semen sampling and reduced semen quality was analysed using unconditional logistic regression, adjusting for potential confounders. MAIN RESULTS AND THE ROLE OF CHANCE: In total, 57 cases and 72 controls redeemed at least one prescription for a drug containing ortho-phthalates in the 90 days before their first semen sample, yielding an adjusted odds ratio (OR) of 1.30 (95% CI: 0.91-1.85) for poor semen quality when compared to males exposed to phthalate-free generic drugs. Similarly, 81 cases and 78 controls exposed to a drug containing polymers had increased odds of poor semen quality (OR = 1.71, 95% CI: 1.24-2.35). Current exposure to polymer containing products from alimentary tract and metabolism drugs was associated with the highest OR of 2.80 (95% CI: 1.63-4.84). Comparing males exposed to drugs containing ortho-phthalates or polymers with males unexposed to prescription drugs, we found adjusted ORs of 1.32 (95% CI: 0.93-1.87) and 1.73 (95% CI: 1.26-2.36), respectively. We saw no clear relationship between degree of exposure and odds of poor semen quality. LIMITATIONS, REASONS FOR CAUTION: The reliance on ICD-10 based register data restricted our ability to relate phthalate exposure to detailed semen parameters. Furthermore, due to imperfections in the registry, we could only include the first semen sample and could not follow semen quality over time. WIDER IMPLICATIONS OF THE FINDINGS: Our results support the likely negative effect of phthalate exposure from medicinal drugs on semen quality. As exposures from medicinal products are readily avoidable, our findings may be of relevance to regulatory authorities. STUDY FUNDING/COMPETING INTEREST(S): This work was supported by Odense University Hospital, Denmark (Grant number A1003). None of the authors declare conflict of interest.

Utility of hematologic and volume, conductivity, and scatter parameters from umbilical cord blood in predicting chorioamnionitis.

We evaluated the utility of routine hematologic parameters and volume, conductivity, and scatter (VCS) parameters from umbilical cord blood in predicting pathologically confirmed chorioamnionitis. Chorioamnionitis is strongly associated with early neonatal sepsis and is the major in utero source of infectious exposure. We prospectively identified mothers who had placenta submitted for pathology and subsequently identified corresponding neonate cord blood sent for routine blood typing (n = 99). Cord blood was then sent for routine complete blood count with differential (CBCD). Among the same neonates, we retrospectively identified those who had peripheral blood sent for CBCD. We collected VCS parameter data, which are used in determining an automated leukocyte differential, from our hematology analyzer. Routine hematologic as well as VCS parameters from both cord and peripheral blood were then evaluated for predicting pathologically confirmed chorioamnionitis. In the study population, the absolute neutrophil count, neutrophil differential, mean neutrophil conductivity, and neutrophil conductivity standard deviation (SD) from cord blood showed the best predictive ability for chorioamnionitis. Among neonates with intrapartum antibiotic prophylaxis exposure, the band differential, immature neutrophil precursor differential, and neutrophil conductivity SD showed the best predictive ability. Lastly, among the neonates who had peripheral blood CBCD, the band differential and immature neutrophil precursor differential showed the best predictive ability. Overall, the peripheral blood band differential and immature neutrophil precursor differential showed better specificity and positive predictive value for chorioamnionitis than the cord blood parameters. However, the cord blood absolute neutrophil count, neutrophil differential, and mean neutrophil conductivity showed better negative predictive value. Cord blood can be a valuable source of diagnostic laboratory testing for neonates because of their small blood volume. This is the first study demonstrating that routine hematologic and VCS parameters from cord blood can be used to predict pathologically confirmed chorioamnionitis.

Tamoxifen's protection against breast cancer recurrence is not reduced by concurrent use of the SSRI citalopram.

Tamoxifen remains an important adjuvant therapy to reduce the rate of breast cancer recurrence among patients with oestrogen-receptor-positive tumours. Cytochrome P-450 2D6 metabolizes tamoxifen to metabolites that more readily bind the oestrogen receptor. This enzyme also metabolizes selective serotonin reuptake inhibitors (SSRI), so these widely used drugs - when taken concurrently - may reduce tamoxifen's prevention of breast cancer recurrence. We studied citalopram use in 184 cases of breast cancer recurrence and 184 matched controls without recurrence after equivalent follow-up. Cases and controls were nested in a population of female residents of Northern Denmark with stages I-III oestrogen-receptor-positive breast cancer 1985-2001 and who took tamoxifen for 1, 2, or most often for 5 years. We ascertained prescription histories by linking participants' central personal registry numbers to prescription databases from the National Health Service. Seventeen cases (9%) and 21 controls (11%) received at least one prescription for the SSRI citalopram while taking tamoxifen (adjusted conditional odds ratio=0.85, 95% confidence interval=0.42, 1.7). We also observed no reduction of tamoxifen effectiveness among regular citalopram users (>or=30% overlap with tamoxifen use). These results suggest that concurrent use of citalopram does not reduce tamoxifen's prevention of breast cancer recurrence.

16(R)-hydroxyeicosatetraenoic acid, a novel cytochrome P450 product of arachidonic acid, suppresses activation of human polymorphonuclear leukocyte and reduces intracranial pressure in a rabbit model of thromboembolic stroke.

OBJECTIVE: Activated polymorphonuclear leukocytes (PMNs) have been suggested to contribute to the development of increased intracranial pressure (ICP). We recently demonstrated that human PMNs produce a novel cytochrome P450-derived arachidonic acid metabolite, 1 6(R)-hydroxyeicosatetraenoic acid [16(R)-HETE], that modulates their function. It was thus of interest to examine this novel mediator in an acute stroke model. METHODS: 16-HETE was assessed initially in a variety of human PMN and platelet in vitro assays and subsequently in an established rabbit model of thromboembolic stroke. A total of 50 rabbits completed a randomized, blinded, four-arm study, receiving 16(R)-HETE, tissue plasminogen activator, both, or neither. Experiments were completed 7 hours after autologous clot embolization. The primary end point for efficacy was the suppression of increased ICP. RESULTS: In in vitro assays, 16(R)-HETE selectively inhibited human PMN adhesion and aggregation and leukotriene B4 synthesis. In the thromboembolic stroke model, animals that received 16(R)-HETE demonstrated significant suppression of increased ICP (7.7 +/- 1.2 to 13.1 +/- 2.7 mm Hg, baseline versus final 7-h time point, mean +/- standard error), compared with either the vehicle-treated group (7.7 +/- 0.9 to 15.8 +/- 2.6 mm Hg) or the tissue plasminogen activator-treated group (7.6 +/- 0.6 to 13.7 +/- 2.1 mm Hg). The group that received the combination of 16(R)-HETE plus tissue plasminogen activator demonstrated no significant change in ICP for the duration of the protocol (8.6 +/- 0.6 to 11.1 +/- 1.2 mm Hg). CONCLUSION: 16(R)-HETE suppresses the development of increased ICP in a rabbit model of thromboembolic stroke and may serve as a novel therapeutic strategy in ischemic and inflammatory pathophysiological states.