Statin use and fatal prostate cancer: a matched case-control study

Association Between Statin Exposure and Incidence and Prognosis of Prostate Cancer: A Meta-analysis Based on Observational Studies

It is widely thought that statins have huge therapeutic potential against prostate cancer (PCA). This study aimed to investigate the effect of statin exposure on PCA incidence and prognosis. PubMed, Web of Science, Embase, and Cochrane databases were searched for observational studies on the association between statin exposure and PCA from inception until July 2022. The primary endpoints were the incidence of PCA and the survival rate. A total of 21 studies were included in this meta-analysis. The pooled estimates showed that exposure to hydrophilic statins was not associated with the incidence of PCA (odds ratio [OR]=0.94, 95% CI=0.88-1.01, P =0.075), while the incidence of PCA was significantly decreased in populations exposed to lipophilic statins compared with the nonexposed group (OR=0.94, 95% CI=0.90-0.98, P =0.001), mainly in Western countries (OR=0.94, 95% CI=0.91-0.98, P =0.006). Subgroup analysis showed that simvastatin (OR=0.83, 95% CI=0.71-0.97, P =0.016) effectively reduced the incidence of PCA. The prognosis of PCA in patients exposed to both hydrophilic (hazard ratio [HR]=0.57, 95% CI=0.49-0.66, P <0.001) and lipophilic (HR=0.65, 95% CI=0.58-0.73, P <0.001) statins were better than in the nonexposed group, and this improvement was more significant in the East than in Western countries. This study demonstrates that statins can reduce the incidence of PCA and improve prognosis, and are affected by population region and statin properties (hydrophilic and lipophilic).

Overcoming Drug Resistance in Advanced Prostate Cancer by Drug Repurposing

Prostate cancer (PCa) is the second most common cancer in men. Common treatments include active surveillance, surgery, or radiation. Androgen deprivation therapy and chemotherapy are usually reserved for advanced disease or biochemical recurrence, such as castration-resistant prostate cancer (CRPC), but they are not considered curative because PCa cells eventually develop drug resistance. The latter is achieved through various cellular mechanisms that ultimately circumvent the pharmaceutical’s mode of action. The need for novel therapeutic approaches is necessary under these circumstances. An alternative way to treat PCa is by repurposing of existing drugs that were initially intended for other conditions. By extrapolating the effects of previously approved drugs to the intracellular processes of PCa, treatment options will expand. In addition, drug repurposing is cost-effective and efficient because it utilizes drugs that have already demonstrated safety and efficacy. This review catalogues the drugs that can be repurposed for PCa in preclinical studies as well as clinical trials.

The Effects of Statins on Prostate Cancer Patients Receiving Androgen Deprivation Therapy or Definitive Therapy: A Systematic Review and Meta-Analysis

Mortality associated with statin use has been reported in prostate cancer (PCa) patients treated with androgen deprivation therapy (ADT) or definitive therapy in several observational studies, although the results have varied. This study aimed to analyze the association of statin use with all-cause mortality and cancer-specific mortality among PCa patients receiving ADT or definitive therapy as their primary treatment and to examine the effect of statin initiation (pre-ADT) timing on outcomes. A systematic literature search of PubMed, the Cochrane library, and Embase was conducted from database inception to 4 October 2021. In total, 12 eligible studies from 976 references were included in the final analysis. The results showed that statin use was associated with a significant reduction in the risks of all-cause mortality (hazard ratio (HR) = 0.73, 95% confidence interval (CI) = 0.64–0.84, p < 0.0001) and cancer-specific mortality (HR = 0.61, 95% CI = 0.49–0.77, p < 0.0001) in PCa patients receiving ADT. However, statin use before ADT initiation did not significantly lower the risk of all-cause mortality (HR = 0.87, 95% CI = 0.66–1.16, p = 0.35) or cancer-specific mortality (HR = 0.84, 95% CI = 0.62–1.13, p = 0.25) in advanced PCa patients receiving ADT. In contrast, statin use was not associated with a significantly reduced risk of all-cause mortality (HR = 0.69, 95% CI = 0.39–1.21, p = 0.20), but it was associated with a reduced risk of cancer-specific mortality (HR = 0.82, 95% CI = 0.68–0.98, p = 0.03) in PCa patients receiving definitive therapy. This review indicated that statin use in combination with ADT was correlated with better all-cause and cancer-specific mortality in PCa patients. However, the beneficial effect might not come from statin use before ADT initiation. In addition, statin use in combination with definitive therapy was correlated with a reduced risk of cancer-specific mortality in PCa patients. In the future, randomized controlled trials are needed to validate the efficacy of statin use in combination with primary treatment for PCa among PCa patients.

Inhibition of Scavenger Receptor Class B Type 1 (SR-B1) Expression and Activity as a Potential Novel Target to Disrupt Cholesterol Availability in Castration-Resistant Prostate Cancer

There have been several studies that have linked elevated scavenger receptor class b type 1 (SR-B1) expression and activity to the development and progression of castration-resistant prostate cancer (CRPC). SR-B1 facilitates the influx of cholesterol to the cell from lipoproteins in systemic circulation. This influx of cholesterol may be important for many cellular functions, including the synthesis of androgens. Castration-resistant prostate cancer tumors can synthesize androgens de novo to supplement the loss of exogenous sources often induced by androgen deprivation therapy. Silencing of SR-B1 may impact the ability of prostate cancer cells, particularly those of the castration-resistant state, to maintain the intracellular supply of androgens by removing a supply of cholesterol. SR-B1 expression is elevated in CRPC models and has been linked to poor survival of patients. The overarching belief has been that cholesterol modulation, through either synthesis or uptake inhibition, will impact essential signaling processes, impeding the proliferation of prostate cancer. The reduction in cellular cholesterol availability can impede prostate cancer proliferation through both decreased steroid synthesis and steroid-independent mechanisms, providing a potential therapeutic target for the treatment of prostate cancer. In this article, we discuss and highlight the work on SR-B1 as a potential novel drug target for CRPC management.

Role of the Sterol Regulatory Element Binding Protein Pathway in Tumorigenesis

Metabolic changes are a major feature of tumors, including various metabolic forms, such as energy, lipid, and amino acid metabolism. Sterol regulatory element binding proteins (SREBPs) are important modules in regulating lipid metabolism and play an essential role in metabolic diseases. In the previous decades, the regulatory range of SREBPs has been markedly expanded. It was found that SREBPs also played a critical role in tumor development. SREBPs are involved in energy supply, lipid supply, immune environment and inflammatory environment shaping in tumor cells, and as a protective umbrella to support the malignant proliferation of tumor cells. Natural medicine and traditional Chinese medicine, as an important part of drug therapy, demonstrates the multifaceted effects of SREBPs regulation. This review summarizes the core processes in the involvement of SREBPs in tumors and provides a comprehensive understanding of the pathways through which natural drugs target the SREBP pathway and regulate tumor progression.

Main Inflammatory Cells and Potentials of Anti-Inflammatory Agents in Prostate Cancer

Prostate cancer is the most common type of cancer and the leading cause of cancer deaths among men in many countries. Preventing progression is a major concern for prostate cancer patients on active surveillance, patients with recurrence after radical therapies, and patients who acquired resistance to systemic therapies. Inflammation, which is induced by various factors such as infection, microbiome, obesity, and a high-fat diet, is the major etiology in the development of prostate cancer. Inflammatory cells play important roles in tumor progression. Various immune cells including tumor-associated neutrophils, tumor-infiltrating macrophages, myeloid-derived suppressor cells, and mast cells promote prostate cancer via various intercellular signaling. Further basic studies examining the relationship between the inflammatory process and prostate cancer progression are warranted. Interventions by medications and diets to control systemic and/or local inflammation might be effective therapies for prostate cancer progression. Epidemiological investigations and basic research using human immune cells or mouse models have revealed that non-steroidal anti-inflammatory drugs, metformin, statins, soy isoflavones, and other diets are potential interventions for preventing progression of prostate cancer by suppressing inflammation. It is essential to evaluate appropriate indications and doses of each drug and diet.

Using human experience to identify drug repurposing opportunities: theory and practice

Retrospective evidence drawn from real-world experience of a medicine's use outside its labelled indication is one of a number of techniques used in drug repurposing (DRP). Relying as it does on large numbers of real incidences of human experience, rather than individual case reports with limited statistical support, preclinical experiments with poor translatability or in silico associations, which are early-stage hypotheses, it represents the best validated form of DRP. Cancer is the most frequent of such DRP examples (e.g. aspirin in pancreatic cancer, hazard ratio = 0.25). This approach can be combined with pathway analysis to provide first-in-class treatments for complex diseases. Alternatively, it can be combined with prospective preclinical studies to uncover a validated mechanism for a new indication, after which a repurposed molecule is chemically optimized.

Longer-term Lipid-lowering Drug Use and Risk of Incident and Fatal Prostate Cancer in Black and White Men in the ARIC Study

Lipid-lowering medications, particularly statins, may protect against aggressive prostate cancer. Fatal prostate cancer, the most clinically relevant outcome, remains understudied for this association. We prospectively studied lipid-lowering medication use and both incident and fatal prostate cancer in black and white men in the Atherosclerosis Risk in Communities (ARIC) study. A total of 6,518 men without cancer at visit 2 (1990-1992), the start of the statin era, were followed for prostate cancer incidence and death through 2012. Medication use was collected during study visits and telephone calls at up to nine time points during follow-up. Cox regression was used to estimate HR and 95% confidence intervals (CI) of total (white N = 541, black N = 259) and fatal (white N = 56, black N = 34) prostate cancer overall and by race. Lipid-lowering medication use was modeled as time-dependent current use or duration (never, <10, and ≥10 years). By visit 4 (1996-1998), 21% of white and 11% of black men had used a lipid-lowering medication, mostly statins. There was a suggestion that current users were less likely to die from prostate cancer than nonusers (HR = 0.67, 95% CI = 0.42-1.07) after multivariable adjustment. We observed no statistically significant differences between black and white men. Current use was not associated with incident prostate cancer, although long-term use was statistically significantly inversely associated with incidence (HR = 0.68; 95% CI = 0.50-0.92). Long-term lipid-lowering medication use was associated with lower risk of prostate cancer. Current use was possibly associated with fatal prostate cancer.

The Impact of Serum Glucose, Anti-Diabetic Agents, and Statin Usage in Non-small Cell Lung Cancer Patients Treated With Definitive Chemoradiation

Introduction: Epidemiologic data indicate diabetes confers an augmented risk of lung cancer development, yet the relationship between hyperglycemia, metabolic agents, and prognosis is unclear. We analyzed the impact of hyperglycemia, anti-diabetic agents, and statins on outcomes in non-small cell lung cancer (NSCLC) patients undergoing chemoradiation.

Method and Materials: In total, data from 170 patients with stage III NSCLC treated at the University of Pittsburgh Medical Center between 2001 and 2014 were obtained for analysis. Kaplan-Meier survival analysis was used to estimate time-to-event for overall survival (OS), disease-free survival, distant metastasis (DM), and loco-regional control (LRC). Blood glucose values (n = 2870), statins, and diabetic medications were assessed both continuously and categorically in univariable and multivariable Cox proportional hazard regression models to estimate hazard ratios and identify prognostic factors.

Results: Tumor volume was a negative prognostic factor for OS, disease-free survival, DM, and LRC (p = 0.001). Tumor stage and treatment time were associated with increased all-cause mortality. Any glucose measurement ≥ 130 mg/dl during treatment (2-year estimate 49.9 vs. 65.8%, p = 0.095) was borderline significant for decreased LRC, with similar trends on multivariable analysis (HR 1.636, p = 0.126) and for OS (HR 1.476, p = 0.130). Statin usage was associated with improved 2-year LRC (53.4 vs. 62.4%, p = 0.088) but not with improvements in survival. Other glycemic parameters, comorbid diabetes diagnosis, or anti-diabetic medications were not significantly associated with outcomes.

Conclusions: There were trends for blood glucose value over 130 mg/dl and statin nonuse being associated with inferior prognosis for LRC in stage III NSCLC patients; glycemic state, statin usage, and glucose-modulating medications were not associated with survival outcomes in multivariable analysis in this retrospective database.

Drug Repositioning for Effective Prostate Cancer Treatment

Drug repositioning has gained attention from both academia and pharmaceutical companies as an auxiliary process to conventional drug discovery. Chemotherapeutic agents have notorious adverse effects that drastically reduce the life quality of cancer patients so drug repositioning is a promising strategy to identify non-cancer drugs which have anti-cancer activity as well as tolerable adverse effects for human health. There are various strategies for discovery and validation of repurposed drugs. In this review, 25 repurposed drug candidates are presented as result of different strategies, 15 of which are already under clinical investigation for treatment of prostate cancer (PCa). To date, zoledronic acid is the only repurposed, clinically used, and approved non-cancer drug for PCa. Anti-cancer activities of existing drugs presented in this review cover diverse and also known mechanisms such as inhibition of mTOR and VEGFR2 signaling, inhibition of PI3K/Akt signaling, COX and selective COX-2 inhibition, NF-κB inhibition, Wnt/β-Catenin pathway inhibition, DNMT1 inhibition, and GSK-3β inhibition. In addition to monotherapy option, combination therapy with current anti-cancer drugs may also increase drug efficacy and reduce adverse effects. Thus, drug repositioning may become a key approach for drug discovery in terms of time- and cost-efficiency comparing to conventional drug discovery and development process.

Influence of serum cholesterol level and statin treatment on prostate cancer aggressiveness

Both cholesterol levels and the use of statins have been described to influence the development and prognosis of prostate cancer (PC). In this retrospective, cross-sectional analysis of consecutive cases from a tertiary referral center we evaluated an association between hypercholesterolemia (≥5.0mmol/l), the use of statins, and advanced/aggressive PC in 767 men with histologically confirmed, clinically localized PC awaiting radical prostatectomy. We found that patients with HCE (n=287, 37.4%) had a significantly higher incidence of poorly differentiated PC (Gleason score ≥7b, 81.1% vs. 4.9%), advanced local tumor stage (≥pT3, 57.7% vs. 22.2%), and nodal involvement (19.8% vs. 1.6%). Multivariate logistic regression analysis identified hypercholesterolemia as a risk factor for aggressive and/or advanced PC (OR 2.01, p<0.001) whereas statin intake showed an odds ratio of 0.49 (p=0.005) indicating a negative association with high-risk PC. Despite a limited number of patients using statins (~9.5%), adjusted and weighed multivariate logistic regression models revealed that preoperative hypercholesterolemia is associated with a diagnosis of high-risk PC which is negatively influenced by statin intake.

Ovarian tumour growth is characterized by mevalonate pathway gene signature in an orthotopic, syngeneic model of epithelial ovarian cancer

Epithelial ovarian cancer (EOC) is the most lethal gynecological cancer and often is not detected until late stages when cancer cells transcoelomically metastasize to the abdomen and typically become resistant to therapy resulting in very low survival rates. We utilize an orthotopic, syngeneic mouse model to study late stage disease and have discovered that the tumor cells within the abdominal ascites are irreversibly re-programmed, with an increased tumorigenicity and resistance to apoptosis. The goal of this study was to characterize the reprogramming that occurred in the aggressive ascites-derived cells (28-2 cells) compared to the original cell line used for tumor induction (ID8 cells). Microarray experiments showed that the majority of genes upregulated in the 28-2 cells belonged to the mevalonate pathway, which is involved in cholesterol biosynthesis, protein prenylation, and activation of small GTPases. Upregulation of mevalonate appeared to be associated with the acquisition of a p53 mutation in the ascites-derived cells. Treatment with simvastatin to inhibit HMG CoA reductase, the rate limiting enzyme of this pathway, induced apoptosis in the 28-2 cell line. Rescue experiments revealed that mevalonate, but not cholesterol, could inhibit the simvastatin-mediated effects. In vivo, daily intraperitoneal simvastatin treatment significantly regressed advanced stage disease and induced death of metastatic tumor cells. These data suggest that ovarian cancer cells become reprogrammed, with genetic mutations, and upregulation of the mevalonate pathway, which facilitates the development of advanced stage disease. The use of statins to inhibit HMGCR may provide novel therapeutic opportunities for the treatment of advanced stage EOC.

Postdiagnosis Statin Use and Mortality in Danish Patients With Prostate Cancer

Purpose Increasing evidence indicates that statin use may reduce mortality from prostate cancer. In this work, we examined whether postdiagnosis statin use was associated with reduced cancer-specific mortality or all-cause mortality among patients with prostate cancer in Denmark. Material and Methods From nationwide Danish registries, we identified all patients with incident prostate adenocarcinoma from 1998 to 2011 and retrieved data on tumor and patient characteristics, drug use, and primary treatment. We defined postdiagnosis use (two or more prescriptions) of statins as a time-varying covariate with 1-year lag. Cox proportional hazards regression models used to compute hazard ratios (HRs) for prostate cancer-specific mortality and all-cause mortality through 2013 associated with postdiagnosis statin use. In secondary and sensitivity analyses, we assessed statin use within exposure periods of 1 year or 5 years after prostate cancer diagnosis and evaluated the influence of prediagnosis statin use. Results Among 31,790 patients, 7,365 died of prostate cancer and 11,811 died from other causes during a median follow-up of 2.8 years (interquartile range, 1.3 to 5.1 years) from 1 year after diagnosis. Postdiagnosis statin use was associated with adjusted HRs of 0.83 (95% CI, 0.77 to 0.89) for prostate cancer mortality and 0.81 (95% CI, 0.76 to 0.85) for all-cause mortality. Similar results were observed in 1-year and 5-year sensitivity analyses. No substantial effect measure modification was found with estimated dose or type of statin, clinical stage, Gleason score, or with prediagnosis statin use; however, patients who were diagnosed early in the study period or who underwent radical prostatectomy or endocrine therapy exhibited slightly lower HRs for prostate cancer mortality with postdiagnosis statin use than did those in the overall analyses. Conclusion Postdiagnosis statin use was associated with reduced mortality from prostate cancer; however, it remains to be established whether this association is causal.

Effects of statins on cancer mortality and progression: A systematic review and meta-analysis of 95 cohorts including 1,111,407 individuals

Statins have been implicated in the regulation of cell proliferation, apoptosis and tumor progression in cancer patients and statin use at the time of cancer diagnosis has been reported to be associated with reduced cancer risk and improved survival, irrespective of concomitant anti-cancer therapy. A systematic literature search of relevant databases through May 2015 was conducted to identify studies assessing the prognostic impact of statin use on prognostic outcomes in cancer patients. Literature search identified 95 cohort studies that met the inclusion criteria. A meta-analysis of 55 articles showed that statin use was significantly associated with decreased risk of all-cause mortality (HR 0.70, 95% Cl 0.66 to 0.74) compared with nonusers. The observed pooled estimates were retained for cancer-specific mortality (HR 0.60, 95% Cl 0.47 to 0.77), progression-free survival (HR 0.67, 95% Cl 0.56 to 0.81), recurrence-free survial (HR 0.74, 95% Cl 0.65 to 0.83) and disease-free survival (HR 0.53, 95% Cl 0.40 to 0.72). These associations almost remained consistent across those outcomes when stratified by publication type, tumour location, study design, sample size, initiation of statins, disease stage, research country, follow-up duration or research hospital involved. Subgroup analyses according to initiation of statins showed postdiagnosis statin users (HR 0.65, 95% Cl 0.54 to 0.79) gained significantly more recurrence-free survival benefit than prediagnosis statin users (HR 0.86, 95% Cl 0.77 to 0.96) (p for interaction = 0.018). Statin therapy has potential survival benefit for patients with malignancy. Further large-scale prospective studies emphasising survival outcomes of individual cancer type are strongly encouraged.

Lipid Raft Integrity Is Required for Survival of Triple Negative Breast Cancer Cells

Purpose

Lipid rafts are cholesterol enriched microdomains that colocalize signaling pathways involved in cell proliferation, metastasis, and angiogenesis. We examined the effect of methyl-β-cyclodextrin (MβCD)-mediated cholesterol extraction on the proliferation, adhesion, invasion, and angiogenesis of triple negative breast cancer (TNBC) cells.

Methods

We measured cholesterol and estimated cell toxicity. Detergent resistant membrane (DRM) and non-DRM fractions were separated using the OptiPrep gradient method. Cell cycles stages were analyzed by flow cytometry, apoptosis was assessed using the TdT-mediated dUTP nick end-labeling assay, and metastasis was determined using a Matrigel invasion assay. Neo-vessel pattern and levels of angiogenic modulators were determined using an in vitro angiogenesis assay and an angiogenesis array, respectively.

Results

The present study found that the cholesterol-depleting agent MβCD, efficiently depleted membrane cholesterol and caused concentration dependent (0.1–0.5 mM) cytotoxicity compared to nystatin and filipin III in TNBC cell lines, MDA-MB 231 and MDA-MB 468. A reduced proportion of caveolin-1 found in DRM fractions indicated a cholesterol extraction-induced disruption of lipid raft integrity. MβCD inhibited 52% of MDA-MB 231 cell adhesion on fibronectin and 56% of MDA-MB 468 cell adhesion on vitronectin, while invasiveness of these cells was decreased by 48% and 52% respectively, following MβCD treatment (48 hours). MβCD also caused cell cycle arrest at the G₂M phase and apoptosis in MDA-MB 231 cells (25% and 58% cells, respectively) and in MDA-MB 468 cells (30% and 38% cells, respectively). We found that MβCD treated cells caused a 52% and 58% depletion of neovessel formation in both MDA-MB 231 and MDA-MB 468 cell lines, respectively. This study also demonstrated that MβCD treatment caused a respective 2.6- and 2.5-fold depletion of tyrosine protein kinase receptor (TEK) receptor tyrosine kinase levels in both TNBC cell lines.

Conclusion

MβCD-induced cholesterol removal enhances alterations in lipid raft integrity, which reduces TNBC cell survival.

Current and Emerging Uses of Statins in Clinical Therapeutics: A Review

Statins, a class of cholesterol-lowering medications that inhibit 3-hydroxy-3-methyl-glutaryl-coenzyme A reductase, are commonly administered to treat atherosclerotic cardiovascular disease. Statin use may expand considerably given its potential for treating an array of cholesterol-independent diseases. However, the lack of conclusive evidence supporting these emerging therapeutic uses of statins brings to the fore a number of unanswered questions including uncertainties regarding patient-to-patient variability in response to statins, the most appropriate statin to be used for the desired effect, and the efficacy of statins in treating cholesterol-independent diseases. In this review, the adverse effects, costs, and drug–drug and drug–food interactions associated with statin use are presented. Furthermore, we discuss the pleiotropic effects associated with statins with regard to the onset and progression of autoimmune and inflammatory diseases, cancer, neurodegenerative disorders, strokes, bacterial infections, and human immunodeficiency virus. Understanding these issues will improve the prognosis of patients who are administered statins and potentially expand our ability to treat a wide variety of diseases.

The effect of statins on prostate cancer recurrence and mortality after definitive therapy: a systematic review and meta-analysis

In this work, we aim to further analyze the association of statins use with biochemical recurrence (BCR) of prostate cancer (PCa) and PCa-specific mortality after definitive therapy. A systematic literature search of PubMed, MEDLINE, and EMBASE through Jul 2015 was conducted. Pooled Hazard ratio (HR) estimates with corresponding 95% confidence intervals (CIs) were calculated using random-effects model. STATA version 10 (Stata corporation, college station, TX) was employed to conduct all statistical analyses. A total of 22 and 8 studies contributed to the biochemical recurrence analysis and PCa-specific mortality, respectively. 13 trials were included for BCR-free survival analysis. The combined result showed statins users had lowered 12% BCR risk of PCa compared with non-users (HR = 0.88, 95%CI: 0.765–0.998) (p < 0.05). The association was null among the men who underwent radical prostatectomy as primary therapy (HR = 0.96, 95%CI: 0.83–1.09), while the improved outcomes had be seen among patients who received radiation therapy (HR = 0.67, 95%CI: 0.48–0.86). After excluding the patients undergoing ADT, participants did not benefit from statins use (HR = 0.94, 95%CI: 0.77–1.11). Meanwhile, long-term statins using did not alter recurrence risk. A lower risk of prostate cancer-specific mortality was observed among statins users (HR = 0.68, 95%CI: 0.56–0.80). There was a plausible trend towards increasing the BCR-free survival rate among statins users.

Statin Use and Prostate Cancer Survival in the Finnish Randomized Study of Screening for Prostate Cancer

BACKGROUND

Recent research has suggested that statins have an effect on prostate cancer prognosis. It is currently unclear how prostate cancer screening, tumor and patient characteristics, or treatment selection may affect this association.

OBJECTIVE

To evaluate the risk of prostate cancer death among statin users. To determine how disease and treatment characteristics affect the association.

DESIGN, SETTING, AND PARTICIPANTS

This is a population-based cohort study consisting of a general male population of Finland participating in the Finnish Randomized Study for Prostate Cancer Screening. The cohort of consisted of 6537 prostate cancer cases diagnosed in the Finnish Randomized Study of Screening for Prostate Cancer population during 1996-2012. The cohort was linked to the National Prescription Database for information on the use of statins and other drugs.

INTERVENTION

Statin use before and after prostate cancer diagnosis compared with nonuse.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Hazard ratios (HRs) for the risk of prostate cancer death by amount, duration, and intensity of statin use. Cox proportional hazards regression with postdiagnostic statin use as a time-dependent variable.

RESULTS

During the median follow-up of 7.5 yr postdiagnosis 617 men died of prostate cancer. Statin use after diagnosis was associated with a decreased risk of prostate cancer death (HR 0.80; 95% confidence interval 0.65-0.98). A decreasing risk trend was observed by increasing intensity of usage (doses/year). The risk decrease was clearest in men managed with androgen deprivation therapy. Prediagnostic statin use was not associated with risk of prostate cancer death (HR 0.92; 95% confidence interval 0.75-1.12).

CONCLUSIONS

Decreased risk of prostate cancer death by statin use after diagnosis suggests that statins may delay or prevent prostate cancer progression. The risk decrease was significant only in men managed with androgen deprivation therapy, but statistical power was limited to estimate the association in men managed with surgery or radiotherapy.

PATIENT SUMMARY

Use of statins after prostate cancer diagnosis was associated with a decreased risk of prostate cancer death. The risk decrease was dose-dependent and observed especially among patients treated with hormone therapy.

Statin use and mortality of patients with prostate cancer: a meta-analysis

OBJECTIVE

The aim of this meta-analysis was to investigate the effect of statin use on the mortality of patients with prostate cancer (PCa).

METHODS

An electronic search of PubMed, Embase, and CENTRAL databases from inception to August 2015 was performed to find eligible studies. Articles investigating the association between statin use and mortality of PCa were identified. Pooled hazard ratios (HRs) and 95% confidence intervals (CIs) were calculated using random- or fixed-effects models.

RESULTS

In total, 13 studies that enrolled 100,536 participants were included in this meta-analysis. Results showed that prediagnostic statin use had a significantly lower risk of both all-cause mortality (ACM; HR, 0.56; 95% CI, 0.38-0.83) and PCa-specific mortality (PCSM; HR, 0.53; 95% CI, 0.36-0.77). Similarly, postdiagnostic statin use was correlated with reductions in both ACM (HR, 0.77; 95% CI, 0.69-0.87) and PCSM (HR, 0.64; 95% CI, 0.52-0.79). When stratified by primary treatment, postdiagnostic use of statins had a 0.4-fold lower risk of ACM in patients with PCa who were treated with local therapy; both pre- and postdiagnostic use of statins was correlated with a significantly lower risk of PCSM in patients who were treated with androgen deprivation therapy.

CONCLUSION

Both pre- and postdiagnostic use of statins is associated with better overall survival and PCa-specific survival. This suggests a need for randomized controlled trials of statins in patients with PCa.

Statin Use Reduces Prostate Cancer All-Cause Mortality: A Nationwide Population-Based Cohort Study

Studies have suggested that statin use is related to cancer risk and prostate cancer mortality. We conducted a population-based cohort study to determine whether using statins in prostate cancer patients is associated with reduced all-cause mortality rates. Data were obtained from the Taiwan National Health Insurance Research Database. The study cohort comprised 5179 patients diagnosed with prostate cancer who used statins for at least 6 months between January 1, 1998 and December 31, 2010. To form a comparison group, each patient was randomly frequency-matched (according to age and index date) with a prostate cancer patient who did not use any type of statin-based drugs during the study period. The study endpoint was mortality. The hazard ratio (HR) and 95% confidence interval (CI) were estimated using Cox regression models. Among prostate cancer patients, statin use was associated with significantly decreased all-cause mortality (adjusted HR = 0.65; 95% CI = 0.60-0.71). This phenomenon was observed among various types of statin, age groups, and treatment methods. Analyzing the defined daily dose of statins indicated that both low- and high-dose groups exhibited significantly decreased death rates compared with nonusers, suggesting a dose-response relationship. The results of this population-based cohort study suggest that using statins reduces all-cause mortality among prostate cancer patients, and a dose-response relationship may exist.

Statin use and risk of prostate cancer: Results from the Southern Community Cohort Study

BACKGROUND

Epidemiologic studies suggest that statin use may be inversely associated with risk of prostate cancer, but prior studies have focused predominantly on non-Hispanic white populations.

METHODS

We evaluated the association between statin use and prostate cancer risk in the Southern Community Cohort Study (SCCS). Study participants were 32,091 men aged 40-79 at baseline, 67% of whom were non-Hispanic black. Between study enrollment (2002-2009) and December 31, 2010, 570 prostate cancer cases were diagnosed, including 324 low-grade cancers (Gleason score <7 or Gleason pattern 3 + 4) and 107 high-grade cancers (Gleason score >7 or Gleason pattern 4 + 3). Analyses of overall prostate cancer were conducted using Cox regression and analyses of grade-specific cancer were conducted using competing risks models.

RESULTS

Ten percent of non-Hispanic black men and 22% of non-Hispanic white men reported use of statins at study enrollment. As compared to non-use, statin use was associated with a non-significant 14% lower risk of prostate cancer in multivariable models (Hazard Ratio [HR]:0.86; 95% Confidence Interval [CI]: 0.63-1.18). This association was stronger for high-grade cancer (HR: 0.62; 95%CI: 0.30, 1.28) than low-grade cancer (HR:0.98; 95%CI: 0.65-1.48). Results were similar by race/ethnicity (p-interaction: 0.41) and did not vary by history of prostate-specific antigen [PSA] screening (p-interaction: 0.65).

CONCLUSIONS

Results suggest no strong association between statin use and prostate cancer risk overall, and further suggest that if a modest protective effect does exist, it does not vary by race/ethnicity and may be restricted to high-grade tumors, although power to detect differences by subgroup was limited.

Postdiagnostic Statin Use and the Risk of Lethal Prostate Cancer in the Health Professionals Follow-up Study

BACKGROUND

Observational studies suggest potential chemopreventive benefits of statins on prostate cancer outcomes, but data on the impact of postdiagnostic use are sparse.

METHODS

We examined the association of postdiagnostic statin use and risk of lethal prostate cancer (metastases or prostate cancer death, N = 242) among 3,949 men diagnosed with localized prostate cancer from the Health Professionals Follow-Up Study between 1992 and 2008 and followed through 2010 (33,302 person years). We used Cox proportional hazards regression models to estimate relative risks and 95% confidence intervals (CI), adjusting for age, time period, time from diagnosis to questionnaire, body mass index, vigorous physical activity, smoking, aspirin use, clinical stage, PSA at diagnosis, Gleason score, primary treatment, and comorbidities.

RESULTS

We found no statistically significant association between postdiagnostic current use of statins or duration of statin usage and the outcome of lethal prostate cancer [N = 242 cases; multivariate HR = 0.97 (95% CI, 0.72-1.31) for current use yes/no; HR = 0.85 (95% CI, 0.59-1.22) for 1 to 5 years of use, 0.96 (95% CI, 0.66-1.38) for 6+ years of use vs. never use].

CONCLUSIONS

We observed little evidence that statin usage after diagnosis of localized prostate cancer reduces risk of progression to metastatic disease or prostate cancer-specific death.

IMPACT

These results do not support statins as a chemopreventive agent for prostate cancer progression.

A review of statin use and prostate cancer

Prostate cancer is the second most common cause of cancer and, when it metastasizes, has a high mortality rate. Statins may affect prostate cancer progression through cholesterol- and pleiotropic-mediated effects. The data on statin effects on prostate cancer has been mixed with benefit most likely occurring in reducing prostate cancer recurrence after radiation therapy and reduced mortality due to prostate cancer. More research is needed in this area to better characterize potential statin-mediated mechanisms that affect cancer. Also, future studies should report patients' anatomic/prognostic stage based on the updated staging system of the American Joint Committee on Cancer, which is a more effective predictor of recurrence and mortality than anatomic stage alone.

Statin use and mortality in cancer patients: Systematic review and meta-analysis of observational studies

BACKGROUND

Previous studies have examined the effect of statin use on the mortality in cancer patients, but the results are inconsistent. A meta-analysis was performed to assess the association with all available studies.

METHODS

Relevant studies were identified by searching PubMed and EMBASE to April 2015. We calculated the summary hazard ratios (HRs) and 95% confidence intervals (CIs) using random-effects models. We estimated combined HRs associated with defined increments of statin use, using random-effects meta-analysis and dose-response meta-regression models.

RESULTS

Thirty-nine cohort studies and two case-control studies involving 990,649 participants were included. The results showed that patients who used statins after diagnosis had a HR of 0.81 (95% CI: 0.72-0.91) for all-cause mortality compared to non-users. Those who used statin after diagnosis (vs. non-users) had a HR of 0.77 (95% CI: 0.66-0.88) for cancer-specific mortality. Prediagnostic exposure to statin was associated with both all-cause mortality (HR=0.79, 95% CI: 0.74-0.85) and cancer-specific mortality (HR=0.69, 95% CI: 0.60-0.79). Stratifying by cancer type, the three largest cancer-type subgroups were colorectal, prostate and breast cancer and all showed a benefit from statin use. HRs per 365 defined daily doses increment were 0.80 (95% CI: 0.69-0.92) for all-cause mortality and 0.77 (95% CI: 0.67-0.89) for cancer-specific mortality. A 1year increment in duration only conferred a borderline decreased risk of death.

CONCLUSIONS

In conclusion, the average effect of statin use, both postdiagnosis and prediagnosis, is beneficial for overall survival and cancer-specific survival.

Statins, aspirin and risk of venous thromboembolic events in breast cancer patients

Venous thromboembolic events (VTE's) are associated with decreased survival in breast cancer patients. Studies suggested that statins reduce the risk of VTE's in the general population. Low dose Aspirin reduces risk of VTE's in high risk populations. The Breast Cancer in Northern Israel Study is a case-control study of consecutive breast cancer cases diagnosed in northern Israel and matched controls. The present analysis was limited to cases with breast cancer enrolled in the study. Data was extracted from Clalit Health Services (CHS) database and from computerized pharmacy records. Out of 3,585 patients enrolled, 261 (7.3%) had a VTE during median follow up of 4.2 years. The 1 and 2 year cumulative incidence was 2.64 and 3.65%. 55.7% of patients used statins, predominantly simvastatin (75.8%). 44.5% used aspirin. In multivariate analysis neither statins nor aspirin use was associated with a reduced risk for a VTE. Unadjusted HR for statin and aspirin was 1.461 (1.018-2.096) and 1.293 (0.846-1.976), respectively, and the adjusted HR were 0.86 (0.648-1.14) and 1.013 (0.737-1.392). Results were similar when only simvastatin use was assessed. Metastatic disease, chemotherapy, age, BMI and presence of comorbidities were significantly associated with risk of VTE's. Our study is the first to look at the effect of statins and aspirin on the incidence of VTE's in patients with breast cancer. In our cohort, statin and aspirin use did not decrease the risk for a VTE. Our results might be explained by use of low potency statins (simvastatin and pravastatin) and by alternate mechanisms for VTE formation in patients with cancer.

Lipid rafts as major platforms for signaling regulation in cancer

Cell signaling does not apparently occur randomly over the cell surface, but it seems to be integrated very often into cholesterol-rich membrane domains, termed lipid rafts. Membrane lipid rafts are highly ordered membrane domains that are enriched in cholesterol, sphingolipids and gangliosides, and behave as major modulators of membrane geometry, lateral movement of molecules, traffic and signal transduction. Because the lipid and protein composition of membrane rafts differs from that of the surrounding membrane, they provide an additional level of compartmentalization, serving as sorting platforms and hubs for signal transduction proteins. A wide number of signal transduction processes related to cell adhesion, migration, as well as to cell survival and proliferation, which play major roles in cancer development and progression, are dependent on lipid rafts. Despite lipid rafts harbor mainly critical survival signaling pathways, including insulin-like growth factor I (IGF-I)/phosphatidylinositol 3-kinase (PI3K)/Akt signaling, recent evidence suggests that these membrane domains can also house death receptor-mediated apoptotic signaling. Recruitment of this death receptor signaling pathway in membrane rafts can be pharmacologically modulated, thus opening up the possibility to regulate cell demise with a therapeutic use. The synthetic ether phospholipid edelfosine shows a high affinity for cholesterol and accumulates in lipid rafts in a number of malignant hematological cells, leading to an efficient in vitro and in vivo antitumor activity by inducing translocation of death receptors and downstream signaling molecules to these membrane domains. Additional antitumor drugs have also been shown to act, at least in part, by recruiting death receptors in lipid rafts. The partition of death receptors together with downstream apoptotic signaling molecules in membrane rafts has led us to postulate the concept of a special liquid-ordered membrane platform coined as "cluster of apoptotic signaling molecule-enriched rafts" (CASMER), referring to raft platforms enriched in apoptotic molecules. CASMERs act as scaffolds for apoptosis signaling compartmentalization, facilitating and stabilizing protein-protein interactions by local assembly of cross-interacting molecules, which leads to apoptosis amplification and a decrease in apoptotic signal threshold. Edelfosine also displaced survival PI3K/Akt signaling from lipid rafts, leading to Akt inhibition, in mantle cell lymphoma cells. Thus, membrane rafts could act as scaffold structures where segregation of pro- from anti-apoptotic molecules could take place. In this review, we summarize our view of how reorganization of the protein composition of lipid raft membrane domains regulates cell death and therefore it might be envisaged as a novel target in the treatment of cancer.

Synergistic simvastatin and metformin combination chemotherapy for osseous metastatic castration-resistant prostate cancer

Docetaxel chemotherapy remains a standard of care for metastatic castration-resistant prostate cancer (CRPC). Docetaxel modestly increases survival, yet results in frequent occurrence of side effects and resistant disease. An alternate chemotherapy with greater efficacy and minimal side effects is needed. Acquisition of metabolic aberrations promoting increased survival and metastasis in CRPC cells includes constitutive activation of Akt, loss of adenosine monophosphate-activated protein kinase (AMPK) activity due to Ser-485/491 phosphorylation, and overexpression of 3-hydroxy-3-methylglutaryl-Coenzyme A reductase (HMG-CoAR). We report that combination of simvastatin and metformin, within pharmacologic dose range (500 nmol/L to 4 μmol/L simvastatin and 250 μmol/L to 2 mmol/L metformin), significantly and synergistically reduces C4-2B3/B4 CRPC cell viability and metastatic properties, with minimal adverse effects on normal prostate epithelial cells. Combination of simvastatin and metformin decreased Akt Ser-473 and Thr-308 phosphorylation and AMPKα Ser-485/491 phosphorylation; increased Thr-172 phosphorylation and AMPKα activity, as assessed by increased Ser-79 and Ser-872 phosphorylation of acetyl-CoA carboxylase and HMG-CoAR, respectively; decreased HMG-CoAR activity; and reduced total cellular cholesterol and its synthesis in both cell lines. Studies of C4-2B4 orthotopic NCr-nu/nu mice further demonstrated that combination of simvastatin and metformin (3.5-7.0 μg/g body weight simvastatin and 175-350 μg/g body weight metformin) daily by oral gavage over a 9-week period significantly inhibited primary ventral prostate tumor formation, cachexia, bone metastasis, and biochemical failure more effectively than 24 μg/g body weight docetaxel intraperitoneally injected every 3 weeks, 7.0 μg/g/day simvastatin, or 350 μg/g/day metformin treatment alone, with significantly less toxicity and mortality than docetaxel, establishing combination of simvastatin and metformin as a promising chemotherapeutic alternative for metastatic CRPC.

Statin use in patients with cirrhosis: a retrospective cohort study

BACKGROUND

Statins reduce cardiovascular risk. Patients with cirrhosis have decreased hepatic clearance of statins and potentially increased risk for complications. No studies assess mortality in patients with biopsy-confirmed cirrhosis.

AIM

Compare mortality in patients with cirrhosis on statins to those not on statins.

METHODS

A retrospective cohort study evaluated patients from 1988 to 2011 at Partners Healthcare Hospitals. The Partners Research Patient Data Registry identified patients with biopsy-proven cirrhosis on statins at biopsy and at least 3 months following. Controls were matched 1:2 by age, gender and Child-Pugh class. Decompensation was defined as ascites, jaundice/bilirubin >2.5 mg/dL, and/or hepatic encephalopathy or variceal hemorrhage. Primary outcome was mortality. Secondary outcome was decompensation in baseline-compensated patients. Chi-square and two-way ANOVA testing compared groups. Cox proportional hazards models for mortality controlled for age, Child-Pugh class, diabetes, coronary artery disease, non-alcoholic steatohepatitis and hepatocellular carcinoma. Kaplan-Meier curves graphed mortality.

RESULTS

Eighty-one statin users and 162 controls were included. Median follow-up: 36 months in statin users and 30 months in controls. 70.4% of patients were Child-Pugh A. Model for End-Stage Liver Disease (MELD), albumin, varices and beta-blocker use were not significantly different between groups. Statin users had lower mortality on multivariate analysis (HR 0.53, p = 0.01), and Child-Pugh A patients had longer survival on Kaplan-Meier analysis. Cox multivariate analysis for decompensation showed lower risk of decompensation with statins while increased decompensation with low albumin, high MELD score and beta-blocker use.

CONCLUSIONS

In patients with cirrhosis, statin therapy is not associated with increased mortality and may delay decompensation.

Commonly used diabetes and cardiovascular medications and cancer recurrence and cancer-specific mortality: a review of the literature

INTRODUCTION

Cancer most commonly arises in the elderly who are often burdened with comorbidities. Medications used for treating these comorbidities may alter cancer prognosis. Understanding the impact of these medications on cancer is important in order to make effective evidence-based decisions about managing comorbidities while improving cancer outcomes.

AREAS COVERED

The evidence on diabetes, statins, antihypertensive and anti-inflammatory medications and their association with cancer recurrence and cancer-specific mortality are reviewed. The strengths and limitations of the existing literature, the current state of the field and future directions are discussed.

EXPERT OPINION

Metformin and aspirin were associated with a reduced risk of cancer recurrence and cancer-specific mortality. The evidence for statins and antihypertensive medications on cancer survival was inconsistent. There were few studies to suggest that any of the medication classes of interest were associated with negative effects on cancer survival. Methodological shortcomings within observational studies, such as confounding, distinguishing between use of medications pre-cancer versus post-cancer diagnosis/treatment, misclassification of exposures/outcomes, informative censoring and competing risks, must be considered. New observational studies addressing these limitations are essential. Some clinical trials are underway to further investigate the beneficial effects of these drugs and completed trials have confirmed results demonstrated in observational studies.

Statin use and the risk of recurrence after radical prostatectomy in a cohort of men with inherited and/or early-onset forms of prostate cancer

OBJECTIVE

To investigate whether the use of statin medications is associated with a reduced risk of biochemical recurrence (BCR) in men with inherited and/or early-onset prostate cancer who have been treated with radical retropubic prostatectomy (RRP).

METHODS

Study patients are men with inherited and/or early-onset prostate cancer enrolled in the University of Michigan Prostate Cancer Genetics Project. Men enrolled in Prostate Cancer Genetics Project were surveyed to determine statin medication use history from 1999 to 2009. Diagnosis and treatment data were taken from medical records. BCR was defined as a single increase in prostate-specific antigen level to ≥0.4 ng/mL after treatment with RRP. Statin use was modeled as a time-dependent variable, and BCR after RRP was both examined using crude Cox proportional hazards models and adjusted for known clinical prognostic factors.

RESULTS

A total of 539 men treated with RRP were included in this study. Of these, 47.9% of men used statin medications, and 115 (21%) men experienced a recurrence. Ever-statin use was not associated with risk of recurrence in crude models (hazards ratio=1.04, 95% confidence interval=0.72-1.49, P value=.86) or in models adjusted for clinical characteristics (hazards ratio=1.06, 95% confidence interval=0.68-1.64, P value=.81). Furthermore, no association was observed when comparing men with high-Gleason grade cancers with those with low-Gleason grade cancers.

CONCLUSION

Statin use was not associated with a reduced risk of BCR after RRP in this study; however, these men at increased risk for prostate cancer represent a subgroup of men who may benefit from further study of statin medication use to slow or prevent BCR.

The failure of cancer chemoprevention

Chemoprevention is proposed as a clinical analogue of population prevention, aimed at reducing likelihood of disease progression, not across the population, but in identified high-risk individuals and not by behavioral or lifestyle modification, but by the use of pharmaceutical agents. Cardiovascular chemoprevention is successful via control of hyperlipidemias and hypertension. However, chemoprevention of cancer is an almost universal failure: not only are some results null; even more frequently, there is an excess of disease, including disease that the agents were chosen specifically to reduce. A brief introduction is followed by the evidence for a wide variety of agents and their largely deleterious, sometimes null, and in one case, largely beneficial, consequences as possible chemopreventives. The agents include (i) those that are food derived and their synthetic analogues: β-carotene, folic acid, retinol and retinoids, vitamin E, multivitamin supplements, vitamin C, calcium and selenium and (ii) agents targeted at metabolic and hormonal pathways: statins, estrogen and antagonists, 5α-reductase inhibitors. There are two agents for which there is good evidence of benefit when the strategy is focused on those at defined high risk but where wider application is much more problematic: aspirin and tamoxifen. The major problems with cancer chemoprevention are presented. This is followed by a hypothesis to explain the failure of cancer chemoprevention as an enterprise, arguing that the central tenets that underpin it are flawed and showing why, far from doing good, cancer chemoprevention causes harm.

Statins, aspirin and risk of thromboembolic events in ovarian cancer patients

OBJECTIVES

Studies suggest that statins and low dose aspirin reduce risk of VTEs in the general population. We aimed to study the effect of these drugs on the incidence of VTEs in patients with ovarian cancer.

METHODS

Patients diagnosed with ovarian cancer between 2000 and 2011 were identified through the Clalit Health Services (CHS) chronic disease registry. Data were extracted from CHS database and from computerized pharmacy records. Use of medications was analyzed as a time dependent covariate in a Cox regression model.

RESULTS

Of 1746 patients 175 (10%) had a VTE during a median follow up of 3.13 years. 83 patients (5.6%) had a VTE within 2 years of diagnosis of ovarian cancer. Use of chemotherapy and stage 3 and 4 at presentation were associated with an increased risk for VTEs. Statins were used by 43.5% of the patients, and 32.3% used aspirin. Aspirin use was associated with a marginally significant reduction in incidence of VTEs within 2 years of diagnosis, HR 0.423 (95% CI 0.182-1.012, p-value 0.053). Statin use was not associated with risk of VTEs.

CONCLUSION

This is the first study looking at the effect of statins and aspirin on the incidence of VTEs in ovarian cancer patients. In our cohort, statins did not decrease the risk for a VTE and aspirin use was associated with a reduced risk which was marginally significant. Our results might be explained by use of low potency statins and by alternate mechanisms for VTE formation in cancer patients.

Use of statins and the risk of death in patients with prostate cancer

PURPOSE

To determine whether the use of statins after prostate cancer diagnosis is associated with a decreased risk of cancer-related mortality and all-cause mortality and to assess whether this association is modified by prediagnostic use of statins.

PATIENTS AND METHODS

A cohort of 11,772 men newly diagnosed with nonmetastatic prostate cancer between April 1, 1998, and December 31, 2009, followed until October 1, 2012, was identified using a large population-based electronic database from the United Kingdom. Time-dependent Cox proportional hazards models were used to estimate adjusted hazard ratios (HRs) with 95% CIs of mortality outcomes associated with postdiagnostic use of statins, lagged by 1 year to account for latency considerations and to minimize reverse causality, and considering effect modification by prediagnostic use of statins.

RESULTS

During a mean follow-up time of 4.4 years (standard deviation, 2.9 years), 3,499 deaths occurred, including 1,791 from prostate cancer. Postdiagnostic use of statins was associated with a decreased risk of prostate cancer mortality (HR, 0.76; 95% CI, 0.66 to 0.88) and all-cause mortality (HR, 0.86; 95% CI, 0.78 to 0.95). These decreased risks of prostate cancer mortality and all-cause mortality were more pronounced in patients who also used statins before diagnosis (HR, 0.55; 95% CI, 0.41 to 0.74; and HR, 0.66; 95% CI, 0.53 to 0.81, respectively), with weaker effects in patients who initiated the treatment only after diagnosis (HR, 0.82; 95% CI, 0.71 to 0.96; and HR, 0.91; 95% CI, 0.82 to 1.01, respectively).

CONCLUSION

Overall, the use of statins after diagnosis was associated with a decreased risk in prostate cancer mortality. However, this effect was stronger in patients who also used statins before diagnosis.

Statin use in relation to prostate cancer outcomes in a population-based patient cohort study

BACKGROUND

We investigated associations between statin use begun before prostate cancer (PCa) diagnosis and PCa recurrence/progression and PCa-specific mortality (PCSM) in a prospective, population-based cohort study.

METHODS

The analysis included 1,001 PCa patients diagnosed in 2002-2005 in King County, Washington. Statin use was assessed at the time of diagnosis using a detailed in-person interview. Prostate cancer recurrence/progression events and cause-specific survival were ascertained from a follow-up survey and the SEER registry. Multivariable competing risk and Cox proportional hazards regression models were used to assess the risk of PCa outcomes according to categories of statin use.

RESULTS

Of the 1,001 PCa patients in our study, 289 men were ever users of statin drugs. During follow-up, we identified 151 PCa recurrence/progression events and 123 total deaths, including 39 PCa-specific deaths. In unadjusted analysis, the risk of PCSM was significantly lower for statin users compared to non-users (1% vs. 5% at 10 years; P < 0.01). In multivariable analysis, the adjusted hazard ratio of PCSM for statin users versus non-users was 0.19 (95% CI: 0.06, 0.56). Statin use was not associated with overall PCa recurrence/progression and other-cause mortality.

CONCLUSIONS

Statin use begun before PCa diagnosis was unrelated to PCa recurrence/progression but was associated with a decrease in risk of PCSM.

Statins and prostate cancer recurrence following radical prostatectomy or radiotherapy: a systematic review and meta-analysis

BACKGROUND

In this meta-analysis, we evaluated associations between statins and recurrence-free survival (RFS) following treatment of localized prostate cancer, with attention to potential benefits among patients treated primarily with radiotherapy (RT) versus radical prostatectomy.

PATIENTS AND METHODS

We identified original studies examining the effect of statins on men who received definitive treatment of localized prostate cancer using a systematic search of the PubMed and EMBASE databases through August 2012. Our search yielded 17 eligible studies from 794 references; 13 studies with hazard ratios (HRs) for RFS were included in the formal meta-analysis.

RESULTS

Overall, statins did not affect RFS (HR 0.90, 95% CI 0.74-1.08). However, in RT patients (six studies), statins were associated with a statistically significant improvement in RFS (HR 0.68; 95% CI 0.49-0.93); this benefit was not observed in radical prostatectomy patients (seven studies). Sensitivity analyses suggested that primary treatment modality may impact the effect of statins on prostate cancer recurrence.

CONCLUSIONS

Our meta-analysis suggests a potentially beneficial effect of statins on prostate cancer patients treated with RT but not among radical prostatectomy patients. Although limited by the lack of randomized data, these results suggest that primary treatment modality should be considered in future studies examining associations between statins and oncologic outcomes.

The poorer cancer survival among the unmarried in Norway: is much explained by comorbidities?

Studies from Norway and other countries have shown that the unmarried have poorer cancer survival than the married, given age, tumor site and stage at diagnosis. The objective of this investigation was to assess the importance of comorbidities for this difference, using disease indicators derived from the Norwegian Prescription Database (NorPD) and information on cancer and sociodemographic characteristics from various other registers, all of which cover the entire Norwegian population. Discrete-time hazard models for cancer mortality up to 2007 were estimated for all 22,925 men and 21,694 women diagnosed with 13 common types of cancer in 2005-7. There were 4898 cancer deaths among men and 4187 among women. Controlling for sociodemographic factors and tumor characteristics, the odds of dying from cancer among never-married men relative to the married was 1.56 (CI 1.41-1.74). The corresponding estimates for widowed and divorced were 1.16 (CI 1.05-1.28) and 1.27 (CI 1.15-1.40). For women, the odds ratios for these three groups were 1.47 (CI 1.29-1.67), 1.10 (CI 1.01-1.20) and 1.14 (CI 1.02-1.27). Several of the 24 indicators of diseases in the year before diagnosis were associated with cancer survival, but their inclusion reduced the excess mortality of the unmarried by only 1-5 percentage points, or about 10% as an overall relative figure. Similar results were found when the four most common cancers were analyzed separately, though there were some differences between them in the role played by the comorbidities. It is possible that important comorbidities are inadequately captured by the included indicators, and perhaps especially for the unmarried. Such concerns aside, the results suggest that the marital status differences in cancer survival to little extent are due to comorbidities (and the few disease risk factors that are also captured), but rather to various other "host factors" or to treatment or care.

Protective effects of l-carnitine and piracetam against mitochondrial permeability transition and PC3 cell necrosis induced by simvastatin

Mitochondrial oxidative stress followed by membrane permeability transition (MPT) has been considered as a possible mechanism for statins cytotoxicity. Statins use has been associated with reduced risk of cancer incidence, especially prostate cancer. Here we investigated the pathways leading to simvastatin-induced prostate cancer cell death as well as the mechanisms of cell death protection by l-carnitine or piracetam. These compounds are known to prevent and/or protect against cell death mediated by oxidative mitochondrial damage induced by a variety of conditions, either in vivo or in vitro. The results provide evidence that simvastatin induced MPT and cell necrosis were sensitive to either l-carnitine or piracetam in a dose-dependent fashion and mediated by additive mechanisms. When combined, l-carnitine and piracetam acted at concentrations significantly lower than they act individually. These results shed new light into both the cytotoxic mechanisms of statins and the mechanisms underlying the protection against MPT and cell death by the compounds l-carnitine and piracetam.

Association between use of β-blockers and prostate cancer-specific survival: a cohort study of 3561 prostate cancer patients with high-risk or metastatic disease

BACKGROUND

We recently reported reduced prostate cancer (PCa)-specific mortality for β-blocker users among patients receiving androgen-deprivation therapy in a health survey cohort including 655 PCa patients. Information on clinical characteristics was limited.

OBJECTIVE

To assess the association between β-blockers and PCa-specific mortality in a cohort of 3561 prostate cancer patients with high-risk or metastatic disease, and to address potential confounding from the use of statins or acetylsalicylic acid (ASA).

DESIGN, SETTING, AND PARTICIPANTS

Clinical information from all men reported to the Cancer Registry of Norway with a PCa diagnosis between 2004 and 2009 (n=24 571) was coupled with information on filled prescriptions between 2004 and 2011 from the Norwegian Prescription Database. Exclusion criteria were low- or intermediate-risk disease; planned radiotherapy or radical prostatectomy; initiation of β-blocker, ASA, or statin use after diagnosis where applicable; missing information on baseline Gleason score, prostate-specific antigen level, T stage or performance status; and missing follow-up.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Cox proportional hazards modelling and competing risk regression modelling were used to analyse the effects of β-blocker use on all-cause and PCa-specific mortality, respectively. Differences between β-blocker users and nonusers regarding baseline clinical characteristics were assessed by the Wilcoxon-Mann-Whitney U test, Pearson chi-square test, and Student t test.

RESULTS AND LIMITATIONS

Median follow-up was 39 mo. β-Blocker use was associated with reduced PCa mortality (adjusted subhazard ratio: 0.79; 95% confidence interval [CI], 0.68-0.91; p value: 0.001). The observed reduction in PCa mortality was independent of the use of statins or ASA. We observed no association with all-cause mortality (adjusted hazard ratio: 0.92; 95% CI, 0.83-1.02). The main limitations of the study were the observational study design and short follow-up.

CONCLUSIONS

β-Blocker use was associated with reduced PCa-specific mortality in patients with high-risk or metastatic disease at the time of diagnosis. Our findings need validation from further observational studies.

Statin use and risk of prostate cancer: a meta-analysis of observational studies

BACKGROUND

Emerging evidence suggests that statins may decrease the risk of cancers. However, available evidence on prostate cancer (PCa) is conflicting. We therefore examined the association between statin use and risk of PCa by conducting a detailed meta-analysis of all observational studies published regarding this subject.

METHODS

Literature search in PubMed database was undertaken through February 2012 looking for observational studies evaluating the association between statin use and risk of PCa. Before meta-analysis, the studies were evaluated for publication bias and heterogeneity. Pooled relative risk (RR) estimates and 95% confidence intervals (CIs) were calculated using random-effects model (DerSimonian and Laird method). Subgroup analyses, sensitivity analysis and cumulative meta-analysis were also performed.

RESULTS

A total of 27 (15 cohort and 12 case-control) studies contributed to the analysis. There was heterogeneity among the studies but no publication bias. Statin use significantly reduced the risk of both total PCa by 7% (RR 0.93, 95% CI 0.87-0.99, p = 0.03) and clinically important advanced PCa by 20% (RR 0.80, 95% CI 0.70-0.90, p<0.001). Long-term statin use did not significantly affect the risk of total PCa (RR 0.94, 95% CI 0.84-1.05, p = 0.31). Stratification by study design did not substantially influence the RR. Furthermore, sensitivity analysis confirmed the stability of results. Cumulative meta-analysis showed a change in trend of reporting risk from positive to negative in statin users between 1993 and 2011.

CONCLUSIONS

Our meta-analysis provides evidence supporting the hypothesis that statins reduce the risk of both total PCa and clinically important advanced PCa. Further research is needed to confirm these findings and to identify the underlying biological mechanisms.

Statin use and the risk of biochemical recurrence of prostate cancer after definitive local therapy: a meta-analysis of eight cohort studies

What's known on the subject? and What does the study add? Over the last few years, several observational studies examined the association of statin use with the risk of biochemical recurrence of prostate cancer after definitive local therapy. The objective of our present study was to summarise available evidence on this subject using the method of meta-analysis. Combined evidence from eight cohort studies did not definitively support the hypothesis that statins influence the risk of biochemical recurrence. However, there was considerable disagreement between individual studies in reported findings and conclusions.

OBJECTIVE

To perform a systematic review and meta-analysis of clinical studies with statin use as the exposure variable and biochemical recurrence after definitive local therapy for prostate cancer as the outcome.

METHODS

Relevant publications were identified through PubMed/Medline/Embase databases. Pooled estimates of the hazard ratios (HRs) were computed using the inverse-variance weighting approach. Heterogeneity was assessed using the Cochran's Q test.

RESULTS

We identified a total of eight eligible studies, all based on the retrospective cohort design. Five of these were based on radical prostatectomy (RP) series and three on radiotherapy (RT) series. There was evidence of heterogeneity in the entire set of eight studies (P = 0.002) as well as in the RP series (P = 0.05) and in the RT series (P = 0.01), when these were considered separately. Based on the random effects inverse-variance weighting approach, pooled estimates of the HRs for the risk of biochemical recurrence in statin users v non-users were 0.91 (95% confidence interval [CI] 0.72-1.13) for the entire set of eight studies, 1.02 (95% CI 0.80-1.29) for the RP series and 0.71 (95% CI 0.44-1.16) for the RT series.

CONCLUSION

The pooled estimates of the HRs were not significantly different from the null value in this meta-analysis; however, evidence of heterogeneity between the studies was present.

Simultaneous modulation of the intrinsic and extrinsic pathways by simvastatin in mediating prostate cancer cell apoptosis

Background

Recent studies suggest the potential benefits of statins as anti-cancer agents. Mechanisms by which statins induce apoptosis in cancer cells are not clear. We previously showed that simvastatin inhibit prostate cancer cell functions and tumor growth. Molecular mechanisms by which simvastatin induce apoptosis in prostate cancer cells is not completely understood.

Methods

Effect of simvastatin on PC3 cell apoptosis was compared with docetaxel using apoptosis, TUNEL and trypan blue viability assays. Protein expression of major candidates of the intrinsic pathway downstream of simvastatin-mediated Akt inactivation was analyzed. Gene arrays and western analysis of PC3 cells and tumor lysates were performed to identify the candidate genes mediating extrinsic apoptosis pathway by simvastatin.

Results

Data indicated that simvastatin inhibited intrinsic cell survival pathway in PC3 cells by enhancing phosphorylation of Bad, reducing the protein expression of Bcl-2, Bcl-xL and cleaved caspases 9/3. Over-expression of PC3 cells with Bcl-2 or DN-caspase 9 did not rescue the simvastatin-induced apoptosis. Simvastatin treatment resulted in increased mRNA and protein expression of molecules such as TNF, Fas-L, Traf1 and cleaved caspase 8, major mediators of intrinsic apoptosis pathway and reduced protein levels of pro-survival genes Lhx4 and Nme5.

Conclusions

Our study provides the first report that simvastatin simultaneously modulates intrinsic and extrinsic pathways in the regulation of prostate cancer cell apoptosis in vitro and in vivo, and render reasonable optimism that statins could become an attractive anti-cancer agent.

Statin use and risk of prostate cancer in the prospective Osteoporotic Fractures in Men (MrOS) Study

BACKGROUND

Statins are a common medication for cholesterol control that may also have effects on cancer-related pathways. The evidence of an association between statins and prostate cancer risk remains ambiguous.

METHODS

We examined statin use in a prospective cohort of 5,069 elderly U.S. men and the risk of incident total, low/high stage, and low/high grade prostate cancer diagnosed between 2000 and 2008. We used multivariate logistic regression models to estimate relative risks and 95% confidence intervals, adjusting for demographic and lifestyle characteristics.

RESULTS

There was no evidence of an association between statin use and any of the prostate cancer endpoints (total, low/high stage, low/high grade prostate cancer), adjusting for age, study site, race, body mass index, marital status, family history of prostate cancer, number of comorbidities, physical activity, and smoking history.

CONCLUSIONS AND IMPACT

In this study of elderly U.S. men, we observed a null association between statin use and risk of prostate cancer.

Cholesterol and prostate cancer

Prostate cancer risk can be modified by environmental factors, however the molecular mechanisms affecting susceptibility to this disease are not well understood. As a result of a series of recently published studies, the steroidal lipid, cholesterol, has emerged as a clinically relevant therapeutic target in prostate cancer. This review summarizes the findings from human studies as well as animal and cell biology models, which suggest that high circulating cholesterol increases risk of aggressive prostate cancer, while cholesterol lowering strategies may confer protective benefit. Relevant molecular processes that have been experimentally tested and might explain these associations are described. We suggest that these promising results now could be applied prospectively to attempt to lower risk of prostate cancer in select populations.

Aspirin and statin nonuse associated with early biochemical failure after prostate radiation therapy

PURPOSE

To present the largest retrospective series investigating the effect of aspirin and statins, which are hypothesized to have antineoplastic properties, on biochemical failure (nadir plus 2 ng/mL) after prostate radiation therapy (RT).

METHODS AND MATERIALS

Between 1989 and 2006, 2051 men with clinically localized prostate cancer received definitive RT alone (median dose, 76 Gy). The rates of aspirin use and statin use (defined as any use at the time of RT or during follow-up) were 36% and 34%, respectively. The primary endpoint of the study was an interval to biochemical failure (IBF) of less than 18 months, which has been shown to be the single strongest predictor of distant metastasis, prostate cancer survival, and overall survival after RT. Patient demographic characteristics and tumor staging factors were assessed with regard to associations with the endpoint. Univariate analysis was performed with the χ(2) test for categorical variables and the Wilcoxon test for continuous variables. Multivariable analysis was performed with a multiple logistic regression.

RESULTS

The median follow-up was 75 months. Univariate analysis showed that an IBF of less than 18 months was associated with aspirin nonuse (P<.0001), statin nonuse (P<.0001), anticoagulant nonuse (P=.0006), cardiovascular disease (P=.0008), and prostate-specific antigen (continuous) (P=.008) but not with Gleason score, age, RT dose, or T stage. On multivariate analysis, only aspirin nonuse (P=.0012; odds ratio, 2.052 [95% confidence interval, 1.328-3.172]) and statin nonuse (P=.0002; odds ratio, 2.465 [95% confidence interval, 1.529-3.974]) were associated with an IBF of less than 18 months.

CONCLUSIONS

In patients who received RT for prostate cancer, aspirin or statin nonuse was associated with early biochemical failure, a harbinger of distant metastasis and death. Further study is needed to confirm these findings and to determine the optimal dosing and schedule, as well as the relative benefits and risks, of both therapies in combination with RT.