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

Association between Statin Use and Clinical Outcomes in Patients with De Novo Metastatic Prostate Cancer: A Propensity Score-weighted Analysis

PURPOSE

Numerous studies have produced conflicting findings regarding the efficacy of statins in prostate cancer treatment. Our objective was to examine the correlation between statin usage and clinical outcomes in Taiwanese men with de novo metastatic prostate cancer.

MATERIALS AND METHODS

We identified patients diagnosed with de novo metastatic prostate cancer from the Chang Gung Research Database spanning the years 2007 to 2020. To minimize confounding bias, we employed the inverse probability of treatment weighting (IPTW) method. Clinical outcomes were assessed using IPTW-adjusted Kaplan-Meier curves. Multivariate Cox proportional hazard regression analysis was utilized to evaluate the association between mortality and clinical factors.

RESULTS

The study cohort comprised 1,716 statin users and 276 non-users. Patients who used statins exhibited a longer median overall survival (85.4 months compared to 58.2 months; p=0.001) and cancer-specific survival (112.6 months compared to 75.7 months; p<0.001) compared to non-users. The median time to the development of castration-resistant status was similar between statin users and non-users (p=0.069). Multivariable Cox proportional hazards regression analysis, after IPTW adjustment, demonstrated that statin use was associated with improved overall survival.

CONCLUSIONS

Our study indicates that the use of statins following a de novo metastatic prostate cancer diagnosis enhances survival outcomes. However, statins did not appear to delay the onset of castration-resistant status. Further large-scale and long-term studies are warranted to investigate the biological effects of statins in men with prostate cancer.

Overcoming statin resistance in prostate cancer cells by targeting the 3-hydroxy-3-methylglutaryl-CoA-reductase

Prostate cancer is the most prevalent malignancy in men. While diagnostic and therapeutic interventions have substantially improved in recent years, disease relapse, treatment resistance, and metastasis remain significant contributors to prostate cancer-related mortality. Therefore, novel therapeutic approaches are needed. Statins are inhibitors of the 3-hydroxy-3-methylglutaryl-CoA reductase (HMGCR), the rate-limiting enzyme of the mevalonate pathway which plays an essential role in cholesterol homeostasis. Numerous preclinical studies have provided evidence for the pleiotropic antitumor effects of statins. However, results from clinical studies remain controversial and have shown substantial benefits to even no effects on human malignancies including prostate cancer. Potential statin resistance mechanisms of tumor cells may account for such discrepancies. In our study, we treated human prostate cancer cell lines (PC3, C4-2B, DU-145, LNCaP) with simvastatin, atorvastatin, and rosuvastatin. PC3 cells demonstrated high statin sensitivity, resulting in a significant loss of vitality and clonogenic potential (up to - 70%; p < 0.001) along with an activation of caspases (up to 4-fold; p < 0.001). In contrast, C4-2B and DU-145 cells were statin-resistant. Statin treatment induced a restorative feedback in statin-resistant C4-2B and DU-145 cells through upregulation of the HMGCR gene and protein expression (up to 3-folds; p < 0.01) and its transcription factor sterol-regulatory element binding protein 2 (SREBP-2). This feedback was absent in PC3 cells. Blocking the feedback using HMGCR-specific small-interfering (si)RNA, the SREBP-2 activation inhibitor dipyridamole or the HMGCR degrader SR12813 abolished statin resistance in C4-2B and DU-145 and induced significant activation of caspases by statin treatment (up to 10-fold; p < 0.001). Consistently, long-term treatment with sublethal concentrations of simvastatin established a stable statin resistance of a PC3SIM subclone accompanied by a significant upregulation of both baseline as well as post-statin HMGCR protein (gene expression up to 70-fold; p < 0.001). Importantly, the statin-resistant phenotype of PC3SIM cells was reversible by HMGCR-specific siRNA and dipyridamole. Our investigations reveal a key role of a restorative feedback driven by the HMGCR/SREBP-2 axis in statin resistance mechanisms of prostate cancer cells.

Post-diagnostic metformin and statin use and risk of biochemical recurrence in Veterans diagnosed with prostate cancer

OBJECTIVE

To evaluate the impact of post-diagnostic metformin or statin use and duration on risk of biochemical recurrence in a racially-diverse cohort of Veterans.

METHODS

The population consisted of men diagnosed with prostate cancer in the Veterans Health Administration and treated with either radical prostatectomy or radiation (Full cohort n = 65,759, Black men n = 18,817, White men n = 46,631, Other = 311). The association between post-diagnostic (1) metformin and (2) statin use with biochemical recurrence was assessed using multivariable, time-varying Cox Proportional Hazard Models for the overall cohort and by race. In a secondary analysis, metformin and statin duration were evaluated.

RESULTS

Post-diagnostic metformin use was not associated with biochemical recurrence (multivariable-adjusted hazard ratio [aHR]: 1.01; 95% confidence interval [CI]: 0.94, 1.09), with similar results observed for both Black and White men. However, duration of metformin use was associated with a reduced risk of biochemical recurrence in the cohort overall (HR: 0.94; 95% CI: 0.92, 0.95) as well as both Black and White men. By contrast, statin use was associated with a reduced risk of biochemical recurrence (HR: 0.83; 95% CI: 0.79, 0.88) in the overall cohort as well as both White and Black men. Duration of statin use was also inversely associated with biochemical recurrence in all groups.

CONCLUSION

Post-diagnostic metformin and statin use have the potential to prevent biochemical recurrence in men diagnosed with prostate cancer.

Exposure to statins post localized prostate cancer diagnosis and risk of metastasis among men who did not receive curative prostate cancer treatment

BACKGROUND

Few studies have evaluated the effect of statin exposure on metastasis risk among prostate cancer patients not receiving curative treatment.

METHODS

We included men diagnosed with localized prostate cancer at an integrated health care system between 1997 and 2006 who did not receive curative treatment within 6 months of diagnosis. We followed these men until a metastatic event, disenrollment, death, or 12/31/2016. We collected all data from electronic health records supplemented by chart review. We used Cox regressions to examine the association between post-diagnostic statin exposure and metastasis, controlling for clinical characteristics and pre-diagnostic statin exposure.

RESULTS

There were 4245 men included. Mean age of diagnosis was 68.02 years. 46.6% of men used statins after prostate cancer diagnosis. During follow-up, 192 men developed metastasis (cumulative incidence rate: 14.5%). In the adjusted Cox model, statin use post-prostate cancer diagnosis was not significantly associated with a metastatic event (HR = 0.97, 95% CI = 0.69, 1.36). Pre-diagnostic statin use was also not associated with development of metastasis (HR = 0.76, 95% CI = 0.53, 1.10). We did not observe a dose-response for the proportion of person-time at-risk post-prostate cancer diagnosis on statins (HR = 0.98 per 10% increase in person-time exposed [95% CI = 0.93, 1.03]).

CONCLUSIONS

We did not find an inverse association between post-diagnosis statin exposure and metastasis development in localized prostate cancer patients who did not receive active treatment. Our results did not offer support to the chemopreventive potential of post-diagnostic statin use among men on active surveillance.

Targeting lipid metabolism in metastatic prostate cancer

Despite key advances in the treatment of prostate cancer (PCa), a proportion of men have de novo resistance, and all will develop resistance to current therapeutics over time. Aberrant lipid metabolism has long been associated with prostate carcinogenesis and progression, but more recently there has been an explosion of preclinical and clinical data which is informing new clinical trials. This review explores the epidemiological links between obesity and metabolic syndrome and PCa, the evidence for altered circulating lipids in PCa and their potential role as biomarkers, as well as novel therapeutic strategies for targeting lipids in men with PCa, including therapies widely used in cardiovascular disease such as statins, metformin and lifestyle modification, as well as novel targeted agents such as sphingosine kinase inhibitors, DES1 inhibitors and agents targeting FASN and beta oxidation.

Statin Use and Survival Among Men Receiving Androgen-Ablative Therapies for Advanced Prostate Cancer: A Systematic Review and Meta-analysis

IMPORTANCE

Epidemiological evidence supports a role for statins in improving survival in advanced prostate cancer, particularly among men receiving androgen-ablative therapies.

OBJECTIVE

To study the association between statin use and survival among men with prostate cancer receiving androgen deprivation therapy (ADT) or androgen receptor axis-targeted therapies (ARATs).

DATA SOURCES

This systemic review and meta-analysis used sources from MEDLINE, EMBASE, Epub Ahead of Print, Cochrane Clinical Trials, Cochrane Systematic Reviews, and Web of Science from inception to September 6, 2022.

STUDY SELECTION

Observational studies reporting associations of concurrent statin use and survival outcomes (in hazard ratios [HRs]).

DATA EXTRACTION AND SYNTHESIS

Two authors independently abstracted all data. Summary estimates pooled multivariable HRs with 95% CIs using the generic inverse variance method with random-effects modeling. A priori specified subgroup and sensitivity analyses were undertaken, and heterogeneity, study quality, and publication bias were evaluated. Confidence in the evidence was assessed using the GRADE (Grading of Recommendations Assessment, Development, and Evaluation) approach.

MAIN OUTCOMES AND MEASURES

Overall mortality and prostate cancer-specific mortality (PCSM).

RESULTS

Twenty-five cohorts of 119 878 men (65 488 statin users [55%]) with more than 74 416 deaths were included. Concurrent statin use was associated with a 27% reduction in the risk of overall mortality (HR, 0.73 [95% CI, 0.66-0.82]; I2 = 83%) and a 35% reduction in the risk of PCSM (HR, 0.65 [95% CI, 0.58-0.73]; I2 = 74%), with substantial heterogeneity in both estimates. Subgroup analyses identified a PCSM advantage associated with statins for men receiving ARATs compared with ADT alone (HR, 0.40 [95% CI, 0.30-0.55] vs 0.68 [95% CI, 0.60-0.76]; P = .002 for difference). Confidence in the evidence was rated low for both outcomes.

CONCLUSIONS AND RELEVANCE

The findings of this meta-analysis show that concurrent statin use was associated with reduced overall mortality and PCSM among men receiving androgen-ablative therapies for advanced prostate cancer. These findings are limited by the observational nature of the data and residual unexplained interstudy heterogeneity. Randomized clinical trials are warranted to validate these results.

Modulation of Plasma Lipidomic Profiles in Metastatic Castration-Resistant Prostate Cancer by Simvastatin

Elevated circulating sphingolipids are associated with shorter overall survival and therapeutic resistance in metastatic castration-resistant prostate cancer (mCRPC), suggesting that perturbations in sphingolipid metabolism promotes prostate cancer growth. This study assessed whether addition of simvastatin to standard treatment for mCRPC can modify a poor prognostic circulating lipidomic profile represented by a validated 3-lipid signature (3LS). Men with mCRPC (n = 27) who were not on a lipid-lowering agent, were given simvastatin for 12 weeks (40 mg orally, once daily) with commencement of standard treatment. Lipidomic profiling was performed on their plasma sampled at baseline and after 12 weeks of treatment. Only 11 men had the poor prognostic 3LS at baseline, of whom five (45%) did not retain the 3LS after simvastatin treatment (expected conversion rate with standard treatment = 19%). At baseline, the plasma profiles of men with the 3LS displayed higher levels (p < 0.05) of sphingolipids (ceramides, hexosylceramides and sphingomyelins) than those of men without the 3LS. These plasma sphingolipids were reduced after statin treatment in men who lost the 3LS (mean decrease: 23−52%, p < 0.05), but not in men with persistent 3LS, and were independent of changes to plasma cholesterol, LDL-C or triacylglycerol. In conclusion, simvastatin in addition to standard treatment can modify the poor prognostic circulating lipidomic profile in mCRPC into a more favourable profile at twice the expected conversion rate.

Statins and renal cell carcinoma: Antitumor activity and influence on cancer risk and survival

Statins are commonly prescribed to reduce plasma cholesterol levels and risk of cardiovascular events and mortality. Statin exposure may have cancer-preventive properties in some solid tumors, including Renal Cell Carcinoma (RCC). Emerging evidences show that statins can inhibit RCC cell growth by inducing cell cycle arrest and apoptosis in a dose- and time-dependent manner. In addition, statins inhibit the phosphorylation of AKT, mammalian target of rapamycin (mTOR), and ERK leading to reduced motility of RCC cells. Interestingly, the potential impact of concomitant statin intake has been recently evaluated in RCC patients treated by targeted therapy or immunotherapy. In this review, we illustrate the most recent data on the preclinical activity of statins in Renal Cell Carcinoma models and discuss the impact of their use on the prevention and survival of patients affected by this tumor.

A propensity score-matched analysis of the impact of statin therapy on the outcomes of patients with non-small-cell lung cancer receiving anti-PD-1 monotherapy: a multicenter retrospective study

BACKGROUND

Many studies have recently reported the association of concomitant medications with the response and survival in patients with non-small-cell lung cancer (NSCLC) treated with cancer immunotherapy. However, the clinical impact of statin therapy on the outcome of cancer immunotherapy in patients with NSCLC is poorly understood.

METHODS

In our database, we retrospectively identified and enrolled 390 patients with advanced or recurrent NSCLC who were treated with anti-programmed cell death-1 (PD-1) monotherapy in clinical practice between January 2016 and December 2019 at 3 medical centers in Japan to examine the clinical impact of statin therapy on the survival of patients with NSCLC receiving anti-PD-1 monotherapy. A propensity score-matched analysis was conducted to minimize the bias arising from the patients' backgrounds.

RESULTS

The Kaplan-Meier curves of the propensity score-matched cohort showed that the overall survival (OS), but not the progression-free survival (PFS), was significantly longer in patients receiving statin therapy. However, a Cox regression analysis in the propensity score-matched cohort revealed that statin therapy was not an independent favorable prognostic factor, although it tended to be correlated with a favorable outcome.

CONCLUSIONS

Statin therapy may be a combination tool for cancer immunotherapy in patients with NSCLC. These findings should be validated in further prospective studies with larger sample sizes.

Improved survival with post-diagnostic metformin and statin use in a racially diverse cohort of US Veterans with advanced prostate cancer

OBJECTIVE

To examine the association between post-diagnostic metformin or statin use with all-cause and prostate cancer (PCa)-specific mortality in men with advanced prostate cancer.

METHODS

Our study consisted of 4572 men (Black = 1352, White = 3192, Other Race = 28) diagnosed with advanced cancer (T4/M1/N1) between 1999 and 2013 in the Veteran Health Administration. The association between post-diagnostic (1) metformin and (2) statin use with all-cause and PCa-specific mortality was examined using multivariable, time-varying Cox Proportional Hazard Models. In a secondary analysis, models were stratified by race.

RESULTS

Post-diagnostic metformin use was associated with a reduced risk of all-cause (Hazard Ratio (HR) 0.84, 95% Confidence Interval (CI): 0.73, 0.96) and PCa-specific death (HR: 0.76, 95% CI: 0.63, 0.91). In stratified analyses, the inverse association between post-diagnostic metformin use and both all-cause PCa-specific mortality was limited to White men. Post-diagnostic statin use was associated with a reduced risk of all-cause (HR: 0.75, 95% CI: 0.68, 0.83) and PCa-specific mortality (HR: 0.72; 95% CI: 0.64, 0.81). In stratified analyses, similar inverse associations were observed for post-diagnostic statin use and all-cause and PCa-specific mortality in both Black and White men.

CONCLUSION

Post diagnostic metformin and statin use may prevent progression to lethal prostate cancer in men with advanced prostate cancer.

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.

Adjuvant Low-dose Statin Use after Radical Prostatectomy: The PRO-STAT Randomized Clinical Trial

PURPOSE

Statin use is reportedly associated with the risk of prostate cancer, outcomes after treatment, and prostate cancer-specific mortality. We sought to determine the efficacy of adjuvant atorvastatin in prostate cancer after radical prostatectomy.

PATIENTS AND METHODS

In this randomized, double-blind trial, we assigned patients with pathologic high-risk prostate cancer to receive either low-dose atorvastatin (20 mg/day, n = 183) or placebo (n = 181) for 1 year after radical prostatectomy. The primary endpoint was the 1-year biochemical recurrence rate. The secondary endpoints included the 5-year biochemical recurrence-free survival and changes in lipid, testosterone, and sex hormone binding globulin levels.

RESULTS

From October 2012 through January 2019, a total of 364 patients underwent randomization. Among 59 total primary end points, 30 (16.4%) and 29 (16.0%) occurred in the atorvastatin and placebo groups, respectively. Atorvastatin did not significantly reduce the primary endpoint of 1-year biochemical recurrence [HR, 0.96; 95% confidence interval (CI), 0.58-1.60]. During a median follow-up of 24 months, 131 patients experienced biochemical recurrence (68 in the atorvastatin group and 63 in the placebo group), representing Kaplan-Meier estimated event rates of 24.0% and 25.4% in the atorvastatin and placebo groups, respectively, at 24 months (HR, 1.00; 95% CI, 0.71-1.41). We observed no significant between-group differences in the testosterone and sex hormone binding globulin levels.

CONCLUSIONS

Among patients with high-risk pathologic features after radical prostatectomy for prostate cancer, 1-year adjuvant use of atorvastatin was not associated with a lower risk of disease recurrence compared with that for placebo. (ClinicalTrials.gov number, NCT01759836).See related commentary by Murtola and Siltari, p. 4947.

The Association Between Statin Use and Outcomes in Patients Initiating Androgen Deprivation Therapy

BACKGROUND

Studies have conflicting results regarding the association between statin use and biochemical recurrence for prostate cancer (PCa). A limited number of studies examining statins in advanced stages report positive results, with a few specifically examining statins and androgen deprivation therapy (ADT).

OBJECTIVE

To perform a post hoc secondary analysis of a randomised controlled trial (RCT) of men initiating ADT to examine the association between statin use and outcomes.

DESIGN, SETTING, AND PARTICIPANTS

Patients with prostate-specific antigen (PSA) >3 ng/ml >1 yr following primary/salvage radiotherapy were enrolled in an RCT of intermittent androgen deprivation (IAD) versus continuous ADT (NCT00003653). Baseline and on-study statin use was modelled as a time-dependent covariate.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

The primary endpoint was overall survival. Models were adjusted for age, time from radiotherapy to ADT, baseline PSA, and prior ADT.

RESULTS AND LIMITATIONS

Of 1364 patients, statin users (585; 43%) were younger (72.7 vs 73.8 yr, p = 0.001) and less likely to have PSA >15 ng/ml (20% vs 25%, p = 0.04). After a median follow-up of 6.9 yr, statin use was associated with reduced overall (hazard ratio [HR]: 0.64; 95% confidence interval [CI] 0.53-0.78, p < 0.001) and PCa-specific (HR: 0.65, 95% CI 0.48-0.87, p = 0.004) mortality. Statin users had 13% longer time to castration resistance, but this did not reach statistical significance (p = 0.15). As an exploratory endpoint, in the IAD arm, statin users had longer time off treatment (median: 0.85 vs 0.64 yr, p = 0.06). Limitations include potential for residual confounding between statin users and nonusers, and confounding by indication.

CONCLUSIONS

In men treated with ADT following primary or salvage radiotherapy, statin use was associated with improved overall and PCa-specific survival. In patients treated with IAD, statin use was associated with a trend towards longer time off treatment. A prospective trial of statins in men commencing ADT is warranted.

PATIENT SUMMARY

We found a favourable association between statin use and survival outcomes in patients initiating androgen deprivation therapy.

Quantitative Prostate MRI Analysis Following Fluvastatin Therapy for Localized Prostate Cancer - A Pilot Study

PURPOSE

To assess the role of multi-parametric MRI (mpMRI) in assessment of tumor response to fluvastatin administered prior to radical prostatectomy.

METHODS

Men with MRI-visible, clinically significant prostate cancer and due to be treated with radical prostatectomy were prospectively enrolled. mpMRI was performed at baseline and following 6-7 week of neoadjuvant oral statin therapy (40 mg fluvastatin, twice daily), prior to prostatectomy. MRI assessment included tumor size, T2 relaxation time, ADC value, K-trans (volume transfer constant), Kep (reflux constant), and Ve (fractional volume) parameters at the 2 time points. Initial prostate needle biopsy cores, prior to starting oral statin therapy, corresponding to site of tumor on radical prostatectomy specimens were selected for analysis. The effect of fluvastatin on tumor proliferation (marker Ki67) and on tumor cell apoptosis (marker cleaved Caspase-3, CC3) were analyzed and correlated with MRI findings.

RESULTS

Nine men with paired MRI studies were included in the study. Binary histopathological data was available for 6 of the participants. No significant change in tumor size (P = 0.898), T2 relaxation time (P = 0.213), ADC value (P = 0.455), K-trans (P = 0.613), Kep (P = 0.547) or Ve (P = 0.883) between the time of biopsy and prostatectomy were observed. No significant change in tumor proliferation (%Ki67-positive cells, P = 0.766) was observed by immunohistochemistry analysis. However, there was a significant increase in tumor cell apoptosis (%CC3-positive cells, P = 0.047).

CONCLUSION

mpMRI techniques may not be sufficiently sensitive to detect the types (or magnitude) of tumor cell changes observed following 6-7 weeks of fluvastatin therapy for prostate cancer.

Impact of statin use on overall and time to biochemical failure following radical prostatectomy or radiation therapy

OBJECTIVES

To assess the impact of statin use on overall and time to biochemical failure following primary treatment of localized prostate cancer (PCa).

SUBJECTS/PATIENTS AND METHODS

1581 patients undergoing radical prostatectomy (RP) or radiation therapy (RT) for primary treatment of PCa between July 2007 and January 2020 were evaluated for statin use, demographic/oncologic characteristics, and biochemical outcomes. Rate of biochemical failure (BF) was assessed overall and at 1, 3, and 5 years; time to BF was estimated with Kaplan-Meier. Logistic and linear regression were used to control for treatment modality and disease characteristics.

RESULTS

The average age was 63.0 ± 7.5 years and median pre-treatment PSA was 6.55 (IQR 4.94). 1473 (93.2%) and 108 (6.8%) underwent RP and RT, respectively. RP patients were younger, had lower pre-PSA, lower BMI, and lower risk disease. At 3.4 ± 2.7 years follow-up, 323 (20.4%) experienced BF. When stratified by statin use, BF overall and within 1, 3, and 5 years were not different. Time to BF, was lower in patients using statins (1.8 ± 1.9 years vs. 2.4 ± 2.6 years; p = 0.016). These results persisted in multivariate analysis, wherein statin use was not associated with BF but was associated with a shorter time to BF.

CONCLUSION

Overall, statin use was not associated with a reduced risk of BF in RP or RT patients. However, for patients with BF, statin use was associated with a decreased time to BF. Future investigations are warranted to further elucidate the impact of statin use on PCa recurrence.

Statin use and risk of prostate cancer biochemical recurrence after radical prostatectomy

BACKGROUND

Multiple studies have investigated the role of statins in prostate cancer (CaP), the leading cause of cancer related death in men. Retrospective cohort studies investigating the correlation between statin use and biochemical recurrence free (BCRF) survival in men with CaP have been inconclusive.

OBJECTIVES

In the largest reported surgical cohort to date, we investigated the effect of statin therapy on BCRF and overall survival in patients with CaP who have undergone radical prostatectomy (RP).

PATIENTS AND METHODS

We performed a retrospective analysis of men (n = 3,088) participating in the NCI funded Specialized Program of Research Excellence (SPORE) in CaP at Northwestern University (NM) in Chicago, Illinois. Patients were treated with RP between 2002 and 2015. Patients in the statin users group received treatment within 2 years prior to or subsequent to RP. Wilcoxon rank-sum and Fisher's exact tests were used to compare age, race, Gleason score, clinical staging, and pathological stage between statin users and nonstatin users.

RESULTS

The analysis identified 1,222 statin users and 1,865 nonusers (mean age 71 years, 92% Caucasian). After a median follow-up time of 49.0 months, the 5-year BCRF survival rate was 93.3% (95% confidence interval [CI]: 91.9-94.8%) among statin users and 88.6% (95% CI: 87.1%-90%) among nonusers (log-rank P< 0.001). After 10 years, the progression-free survival (PFS) was 91.7% (95% CI: 90.1%-93.3%) among statin users and 86.5% (95% CI: 84.4%-88.2%) among nonusers (log-rank P< 0.001).

CONCLUSIONS

Extended follow-up data in this large surgical cohort show statin use improves BCRF but not overall survival in RP patients.

Statins as Anticancer Agents in the Era of Precision Medicine

Statins are widely prescribed cholesterol-lowering drugs that inhibit HMG-CoA reductase (HMGCR), the rate-limiting enzyme of the mevalonate metabolic pathway. Multiple lines of evidence indicate that certain cancers depend on the mevalonate pathway for growth and survival, and, therefore, are vulnerable to statin therapy. However, these immediately available, well-tolerated, and inexpensive drugs have yet to be successfully repurposed and integrated into cancer patient care. In this review, we highlight recent advances and outline important considerations for advancing statins to clinical trials in oncology.

The Suggested Unique Association Between the Various Statin Subgroups and Prostate Cancer

BACKGROUND

The chemopreventive effect of various medications in prostate cancer (PCa) has gained interest. Specifically, the potential impact of statins on PCa incidence has been studied, but solely as a "drug family" overlooking the distinctive pharmacological properties of its two main subgroups: hydrophilic and hydrophobic statins.

OBJECTIVE

To assess the impact of statin subgroups on PCa-specific mortality (PCSM), PCa diagnosis, and undergoing another prostate biopsy.

DESIGN, SETTING, AND PARTICIPANTS

This is a population-based cohort study in Ontario identifying all men aged ≥66 yr with a history of a single negative prostate biopsy (representing healthy men at risk for PCa) between 1994 and 2016, who were not on any of the analyzed medications prior to the study, with a median follow-up of 9.42 yr (interquartile range 8.03 yr).

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Using multivariable cause-specific hazard models with time-dependent covariates, the association of hydrophobic and hydrophilic statins with all study outcomes was analyzed. Other putative chemopreventive medications (including alpha-blockers, 5-alpha-reductase inhibitors, and proton-pump inhibitors), age, rurality, comorbidities, and study inclusion year were included in the models.

RESULTS AND LIMITATIONS

Overall, 21 512 men were identified. Statins were taken by 11 401 patients (50.3%), 5184 men (24.1%) were diagnosed with PCa, and 805 (3.7%) died from it. Overall, 7556 patients (35.1%) underwent another biopsy. Any use of hydrophilic statins was associated with a 32.4% (95% confidence interval [CI] 12.9-47.5%), a 20% (95% CI 10-28%), and an 18% (95% CI 6.1-27.3%) decreased risk of PCSM, undergoing another prostate biopsy, and being diagnosed with PCa, respectively. Hydrophobic statins were associated with 17% (95% CI 2-31%) decreased PCSM. The study is limited by its retrospective nature, selection bias, and accompanying health-administrative database inaccuracies.

CONCLUSIONS

Use of any statin may be associated with a lower hazard of PCSM, with hydrophilic statins showing a greater association with decreased PCa diagnosis rates. Preferentially prescribing one statin subgroup over another in men needs further exploration.

PATIENT SUMMARY

Use of any statin may be associated with a lower probability of dying from prostate cancer. Hydrophilic statins (rosuvastatin and pravastatin) may also be more positively associated with a lower risk of undergoing an additional prostate biopsy and being diagnosed with prostate cancer in men aged ≥66 yr.

The association of serum lipid levels with colorectal cancer recurrence

BACKGROUND

Biologic and epidemiologic evidence suggests that tumor cells depend on reprogrammed lipid metabolic function for survival and growth. Lipids may promote tumor recurrence by providing energy needed for proliferation. Studies have found associations of serum lipids with cancer incidence, mortality, and disease-free mortality, though they have yet to evaluate the prognostic potential of serum lipids for colorectal cancer (CRC) recurrence.

METHODS

341 Danish CRC patients who underwent surgical resection were actively followed between 2003-2011 from date of surgery until December 31, 2012, or death. Serum lipids including low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), and triglycerides (TG), were collected at regular intervals. Lipids were assigned as time-varying exposures evaluated with a one-year lag. Cox proportional hazards models were used to assess recurrence rate, adjusting for clinically relevant covariates. A restricted analysis was performed in a group of non-statin users (n = 236).

RESULTS

Among 341 CRC patients, increased HDL-C appeared to have a beneficial impact on recurrence-free survival (RFS) for CRC patients, especially among statin users (hazard ratio [HR] for 0.1 mmol/L increase = 0.58; 95 % confidence interval [CI]: 0.43, 0.78). Increased LDL-C and TG were not associated with RFS. Increased lipids showed a near-null effect on CRC recurrence [e.g. HR (95 % CI) for 0.1 mmol/L increase LDL = 1.01 (0.97, 1.19)] among non-statin users.

CONCLUSION

Serum lipid levels of LDL-C and TG do not appear to be associated with CRC recurrence. Further investigation of the role of HDL-C in CRC recurrence may be of interest based on the suggestive inverse association observed here.

Rates of underuse of statins among cancer survivors versus controls: NHANES 2011-2016

PURPOSE

Cardiovascular disease (CVD) is a major non-cancer cause of mortality among cancer survivors, and statin therapy is the mainstay of cardiovascular risk management. However, little is known about adherence to statin therapy relative to current guidelines for the management of cholesterol among cancer survivors. We investigated the prevalence of statin-eligible but untreated individuals among cancer survivors and factors associated with underuse of statins.

METHODS

We used US National Health and Nutrition Examination Survey data (2011-2016) and identified 706 cancer survivors and matched controls (1:2) by age and sex. We identified participants who met the American College of Cardiology/American Heart Association (2018) guidelines but were not currently in treatment. We estimated the proportion of patients who were statin-eligible but untreated and performed multivariable logistic regression analysis to identify the factors associated with underuse of statins.

RESULTS

The mean age of the total sample was 62.2 years (standard deviation, 9.1). Among the total participants, 37.5% of cancer survivors and 37.2% of controls were statin-eligible but untreated. The crude statin-eligible untreated proportion was 41.2% among cancer survivors who had received a cancer diagnosis within 3 years and 40.3% among long-term survivors of 10 years or more. In multivariate analysis, old age, male sex, lack of a usual source of care, current smoking, and low household income were significantly associated with statin-eligible untreated status.

CONCLUSIONS AND IMPLICATIONS FOR CANCER SURVIVORS

More than one-third of cancer survivors were statin-eligible but untreated under current guidelines. There is room for improvement to reduce the burden of non-cancer mortality by managing traditional cardiovascular risk factors.

Associations among statins, preventive care, and prostate cancer mortality

BACKGROUND

Increasing evidence indicates an association between statins and reduced prostate cancer-specific mortality (PCSM). However, significant bias may exist in these studies. One particularly challenging bias to assess is the healthy user effect, which may be quantified by screening patterns. We aimed to evaluate the association between statin use, screening, and PCSM in a dataset with detailed longitudinal information.

METHODS

We used the Veterans Affairs Informatics and Computing Infrastructure to assemble a cohort of patients diagnosed with prostate cancer (PC) between 2000 and 2015. We collected patient-level demographic, comorbidity, and tumor data. We also assessed markers of preventive care utilization including cholesterol and prostate specific antigen (PSA) screening rates. Patients were considered prediagnosis statin users if they had at least one prescription one or more years prior to PC diagnosis. We evaluated PCSM using hierarchical Fine-Gray regression models and all-cause mortality (ACM) using a cox regression model.

RESULTS

The final cohort contained 68,432 men including 40,772 (59.6%) prediagnosis statin users and 27,660 (40.4%) nonusers. Prediagnosis statin users had higher screening rates than nonusers for cholesterol (90 vs. 69%, p < 0.001) and PSA (76 vs. 67%, p < 0.001). In the model which excluded screening, prediagnosis statin users had improved PCSM (SHR 0.90, 95% CI 0.84-0.97; p = 0.004) and ACM (HR 0.96, 95% CI 0.93-0.99; p = 0.02). However, after including cholesterol and PSA screening rates, prediagnosis statin users and nonusers showed no differences in PCSM (SHR 0.98, 95% CI 0.91-1.06; p = 0.59) or ACM (HR 1.02, 95% CI 0.98-1.05; p = 0.25).

CONCLUSION

We found that statin users tend to have more screening than nonusers. When we considered screening utilization, we observed no relationship between statin use before a prostate cancer diagnosis and prostate cancer mortality.

Statin and Cancer Mortality and Survival: An Umbrella Systematic Review and Meta-Analysis

The aim of this study is to provide an overview and understand the strength of evidence and the extent of potential biases and the validity of claimed associations between the use of statins and cancer mortality or survival. We performed a comprehensive umbrella review of meta-analyses and systematically appraised the relevant meta-analyses of observational studies on the associations between statin use and cancer mortality or survival in various kinds of cancer. We searched the PubMed database and screened the reference list of relevant articles. We obtained the summary effect, 95% confidence interval, heterogeneity, and also examined small study effects and 95% prediction intervals for effect sizes, and the level of evidence was determined from the criteria. Regarding cancer mortality, statin use showed convincing evidence for an association with a reduced cancer-specific mortality rate for colorectal cancer. Four associations with reduced all-cause mortality (for breast cancer, colorectal cancer, endocrine-related gynecological cancer, and ovarian cancer) had a suggestive evidence. Moreover, analyses in nine cancers showed a weak level of evidence, while the remaining 15 did not indicate significant changes in either direction. Although there was a preventive effect of statin on cancer mortality in some cancer types, the evidence supporting the use of statins to reduce cancer mortality or survival was low.

The effect of statins on advanced prostate cancer patients with androgen deprivation therapy or abiraterone/enzalutamide: A systematic review and meta-analysis

WHAT IS KNOWN AND OBJECTIVE

To evaluate the effects of statin use on the treatment outcomes (i.e. overall survival and cancer-specific survival) among advanced prostate cancer (PCa) patients treated with androgen deprivation therapy (ADT) or abiraterone/enzalutamide.

METHODS

The original studies, examining the effects of statins on the outcomes (i.e. overall survival and cancer-specific survival) among PCa patients treated with ADT or abiraterone/enzalutamide, were identified through a systematic search by two independent reviewers in the PubMed, Cochrane, Embase, American Society of Clinical Oncology and European Society of Medical Oncology databases. Databases were searched using keywords (abiraterone OR enzalutamide OR androgen deprivation therapy) AND statin. In total, nine eligible studies from 111 references were included for final analysis.

RESULTS AND DISCUSSION

Statin use significantly lowered the risk of all-cause mortality (100 709 patients, HR = 0.73, 95%CI = 0.64-0.83, P < .00001) and the risk of cancer-specific mortality (100 343 patients, HR = 0.64, 95% CI = 0.53-0.77, P < .00001) in advanced PCa patients treated with ADT. The sensitivity analysis showed that the results were reliable. However, it could not generate reliable evidence in patients with metastatic castration-resistant prostate cancer (mCRPC) treated with abiraterone/enzalutamide, as relevant studies were limited and had inconsistent results.

WHAT IS NEW AND CONCLUSION

The review indicated that the use of statins in combination with ADT was associated with better all-cause survival and cancer-specific survival in patients with advanced PCa. Randomized controlled trials should be conducted to establish efficacy of statins among PCa patients.

Metformin and statins: a possible role in high-risk prostate cancer

Aim and background

There is increasing evidence that statins and oral anti-diabetic drugs, such as metformin, can have a favorable role in advanced prostate cancer treatment.Metformin has been shown to inhibit proliferation of tumor cells in vitro and statins inhibit carcinogenesis by suppressing angiogenesis/invasion mechanisms. However, clinical evidence on the protective effect of these drugs is still weak.The purpose of this study is to analyze if these drugs have an impact on Biochemical-Failure-Free-Survival (BFFS) and on Distant-Failure-Free-Survival (DFFS) in localized high-risk prostate cancer.

Material and Methods

From 2002-2016, 447 patients with histologically confirmed high-risk prostate cancer were retrospectively evaluated. All patients received radiotherapy and androgen deprivation therapy. Biochemical recurrence was determined by the Phoenix criteria and metastatic patients were defined by the presence of radiological metastasis. Survival analysis was performed using the Kaplan-Meier method.

Results

175 patients were treated with statins (65.3 % with a dose ≤ 20 mg/day) and 70 with metformin (75.7 % with a dose ≤ 1700 mg/day). Median follow-up was 88 months (1-194) with no differences in BFFS and DFFS between metformin and non-metformin patients (77.4 % versus 80 %, p = 0.91 and 89.4 % versus 88.7 %, p = 0.56, respectively). We did not find a statistical difference in BFFS and DFFS in patients taking higher doses of those drugs.

Conclusion

Metformin and statins were not associated with BFFS or DFFS improvement in our analysis. However, the small number of patients treated with these drugs limits the reliability of the results and prospective studies are needed.

Protective effect of Chuquiraga spinosa Lessing associated with simvastatin on N-Nitroso-N-methylurea (NMU)-induced prostate cancer in rats

Background and objective

Chuquiraga spinosa Lessing (ChS) has shown protective effect on  N-Nitroso-N-methylurea (NMU)-induced prostate cancer in rats. Currently, statins are being studied for their pro-apoptotic and antimetastatic effects. The main objective of this research was to determine the protective effect associated with the oral administration of simvastatin and ethanolic extract of the aerial parts of ChS in the prevention of prostate cancer.

Methods

Fifty-six albino male rats were randomized into seven groups: I) negative control: physiological serum: 2 mL/kg; II) TCN: testosterone 100 mg/kg + cyproterone 50 mg/kg + NMU 50 mg/kg; III) TCN + S40 (simvastatin 40 mg/kg); IV) TCN + ChS250 (ChS 250 mg/kg); V) TCN + ChS50 (ChS 50 mg/kg) + S40; VI) TCN + ChS250 (ChS 250 mg/kg) + S40; and VII) TCN + ChS500 (ChS 500 mg/kg) + S40. The antioxidant activity was tested by using (2,2-diphenyl-1-picrylhydrazyl) (DPPH) assay. Hematology, toxicological biochemical parameters, prostate-specific antigen (PSA), histology and prostate size were evaluated as main indicators of protective effect.

Results

Triglyceride values were decreased in the groups receiving ChS, being significant (P=0.02) in IV and VII group compared to cancer-inducing group (TCN). In groups that received ChS, PSA levels (P=0.71) were significant compared with TCN group. The VII group had the lowest prostate volume by sonography. The TCN group showed multiple foci of high-grade prostatic intraepithelial neoplasia (HG-PIN) with the presence of cells in mitosis; whilst, groups V and VI had few areas of HG-PIN.

Conclusion

In experimental conditions, the ethanolic extract of C. spinosa in association with simvastatin showed a protective effect on prostate cancer through hypolipidemic and antioxidant activity.

Prostate cancer survival among statin users after prostatectomy in a Finnish nationwide cohort

BACKGROUND

Improved prostate cancer (PCa) survival by statin use has been reported among PCa patients managed with radiation or androgen deprivation therapy (ADT), while results are controversial for men managed surgically. We evaluate the association between cholesterol-lowering medication with initiation of ADT and disease-specific death among PCa cases who underwent radical prostatectomy in Finland between 1995 and 2013.

METHODS

The study cohort included 14 424 men with PCa who underwent radical prostatectomy in Finland between 1995 and 2013. Cases were identified from national hospital discharge registry. Clinical data were amended from patient files of the treating hospitals. Information on co-morbidities, additional radiation- or chemotherapy, and causes of deaths were collected from national registries. Personal-level data on medication use during 1995-2014 were gathered from national prescription database. Registry linkages were carried out using personal identification number. Lipid-lowering drugs were categorized into statins and non-statin drugs. Risk of PCa death and initiation of ADT was analyzed using Cox-regression model with adjustment for age, radiation therapy, chemotherapy, co-morbidities and other drug use. Statin use was analyzed as time-dependent variable. Delayed risk associations were evaluated in lag-time analysis.

RESULTS

Compared to non-users the risk of PCa death was significantly lower among statin users before PCa diagnosis (HR 0.70, 95%CIs 0.52-0.95). For statin use after PCa diagnosis the risk was lowered in age-adjusted analysis (HR 0.76 95%CIs 0.62-0.93) but not after multivariable-adjustment. Post-diagnostic statin use was associated with improved PCa-specific survival in 1, 3 and 5 years lag-time analyses. The risk reduction was clearest for statin use initiated 5 years earlier (HR 0.71 95%CIs 0.55-0.92). Use of statins both before and after PCa diagnosis was associated with reduced risk of ADT use (HR 0.72 95%CIs 0.65-0.80 and HR 0.73, 95%CI 0.67-0.80, respectively). The risk of ADT decreased by increasing intensity of statin use before diagnosis.

CONCLUSION

Statin use among surgically treated PCa patients has significant association with decreased risk of starting ADT and PCa death. The risk is lowered especially among men with statin use before PCa diagnosis and in men who used statins at high-dose. Our results are hypothesis generating due to retrospective study design.

An actionable sterol-regulated feedback loop modulates statin sensitivity in prostate cancer

OBJECTIVE

The statin family of cholesterol-lowering drugs has been shown to induce tumor-specific apoptosis by inhibiting the rate-limiting enzyme of the mevalonate (MVA) pathway, HMG-CoA reductase (HMGCR). Accumulating evidence suggests that statin use may delay prostate cancer (PCa) progression in a subset of patients; however, the determinants of statin drug sensitivity in PCa remain unclear. Our goal was to identify molecular features of statin-sensitive PCa and opportunities to potentiate statin-induced PCa cell death.

METHODS

Deregulation of HMGCR expression in PCa was evaluated by immunohistochemistry. The response of PCa cell lines to fluvastatin-mediated HMGCR inhibition was assessed using cell viability and apoptosis assays. Activation of the sterol-regulated feedback loop of the MVA pathway, which was hypothesized to modulate statin sensitivity in PCa, was also evaluated. Inhibition of this statin-induced feedback loop was performed using RNA interference or small molecule inhibitors. The achievable levels of fluvastatin in mouse prostate tissue were measured using liquid chromatography-mass spectrometry.

RESULTS

High HMGCR expression in PCa was associated with poor prognosis; however, not all PCa cell lines underwent apoptosis in response to treatment with physiologically-achievable concentrations of fluvastatin. Rather, most cell lines initiated a feedback response mediated by sterol regulatory element-binding protein 2 (SREBP2), which led to the further upregulation of HMGCR and other lipid metabolism genes. Overcoming this feedback mechanism by knocking down or inhibiting SREBP2 potentiated fluvastatin-induced PCa cell death. Notably, we demonstrated that this feedback loop is pharmacologically-actionable, as the drug dipyridamole can be used to block fluvastatin-induced SREBP activation and augment apoptosis in statin-insensitive PCa cells.

CONCLUSION

Our study implicates statin-induced SREBP2 activation as a PCa vulnerability that can be exploited for therapeutic purposes using clinically-approved agents.

Statin and metformin therapy in prostate cancer patients with hyperlipidemia who underwent radiotherapy: a population-based cohort study

Purpose

To evaluate the association between the use of statins and/or metformin and patient survival in prostate cancer patients in Taiwan.

Subjects and methods

Newly diagnosed prostate cancer patients who had hyperlipidemia and received radiotherapy were identified from the National Health Insurance Research Database 2000–2010. The survival rate was estimated by the Kaplan–Meier method. Univariate and multivariate Cox regression analyses were performed to examine the association of mortality. Sensitivity analysis was performed to assess the risk of mortality in patients with diabetes.

Results

The study included 567 patients. Patients who used statins or metformin after prostate cancer diagnosis had longer average survival times (9.3 years and 8.1 years, respectively; P=0.001) compared with patients who persistently used or used the medicines prior to cancer diagnosis. Multivariate Cox regression analysis found that patients treated with statins after cancer diagnosis were significantly associated with a lower risk of mortality (aHR =0.24, 95% CI =0.09–0.66) compared to patients who did not use statins during the study period. Patients treated with metformin after cancer diagnosis were significantly associated more with an increased risk of mortality (aHR =6.78, 95% CI =2.45–18.77) compared to patients who did not use metformin during the study period. Sensitivity analysis revealed that the average survival time was similar among different medicine use groups in patients with diabetes.

Conclusion

The finding suggests that statins and metformin use after prostate cancer diagnosis may increase survival in patients with hyperlipidemia and radiotherapy.

The association between statin use and endometrial cancer survival outcome: A meta-analysis

BACKGROUND

Previous studies on the association between statin use and survival outcomes in gynecologic cancers have presented conflicting results. No independent studies to elucidate the association between statin use and survival outcomes of endometrial cancer (EC) have been conducted.

METHODS

To gather updated evidence, we carried out an extensive literature search on Medline (PubMed and OvidSP), Embase, Cochrane Library, China National Knowledge Infrastructure (CNKI), wanfang data, and Vip network to identify all potential studies on the effect of statins on the prognosis of endometrial carcinoma. The design and quality of all studies were evaluated, and a fixed-effects model was used to calculate pooled hazard ratios (HRs) for overall survival (OS) and disease-specific survival (DSS).

RESULTS

Of the 219 articles screened, 9 articles were eligible, including 8 articles and 1 abstract. A total of 5923 patients with endometrial cancer who used statins were identified. Statin use was related to increased overall survival (HR, 0.80; 95% confidence interval [CI], 0.66-0.95, without significant heterogeneity, I = 52%, P = .080). Statin users also had increased disease-specific survival (HR, 0.69; 95% CI, 0.61-0.79, I = 0.0%).

CONCLUSION

Statins are beneficial to the survival outcome of patients with endometrial cancer. The selection of statins as a 1st-line agent seems justified for endometrial carcinoma.

Statin reduces the risk of dementia in diabetic patients receiving androgen deprivation therapy for prostate cancer

BACKGROUND

Androgen deprivation therapy (ADT) has been reported to increase the risk of dementia. Statin use decreases the risk of dementia. This study is aimed to investigate the association of statin use and dementia in type 2 diabetic (T2DM) patients receiving ADT.

METHODS

Using the National Health Insurance Research Database of Taiwan, we conducted a population-based nationwide cohort study of T2DM patients newly diagnosed with prostate cancer (PCa) between 1998 and 2013. To test statin effects on dementia in T2DM patients receiving ADT, cox proportional hazards models with 1:1 propensity score-matched analysis were used. We divided the study subjects into a statin group and a statin-naive group. The primary outcome was dementia.

RESULTS

Of the 9855 selected T2DM patients newly diagnosed with PCa between 1998 and 2013, 5427 patients received ADT for their PCa. After propensity score matching, 1006 statin users and 1006 non-statin users were included in the study cohort, with a mean follow-up period of 3.5 years for the statin group. Among those patients, 179 (8.7%) were newly diagnosed with dementia. A propensity score-matched analysis (hazard ratio = 0.70, 95% confidence interval = 0.52-0.94) demonstrated a significantly decreased risk of subsequent dementia in the statin users with an absolute risk reduction by 1%. A significant decrease in the risk of dementia with increasing statin duration was also demonstrated (P for trend = 0.002).

CONCLUSIONS

Statin use in T2DM patients receiving ADT for PCa had decreased risk of dementia, with statin adherence and intensity augmenting this benefit.

Effect of statins type on incident prostate cancer risk: a meta-analysis and systematic review

The aim of this study is to investigate the effect of statins type or even when grouping statins by hydrophilic or hydrophobic nature on prostate cancer risk. A literature search was performed without language restrictions using the databases of PubMed (1984.1-2015.3), MEDLINE (1984.1-2015.3), and EMBASE (1990.1-2015.3). Two independent reviewers appraised eligible studies and extracted data. Weighted averages were reported as relative risk (RR) with 95% confidence intervals (CI). Statistic heterogeneity scores were assessed with the standard Cochran's Q-test and I2 statistic. Publication bias was detected using the Begg's and Egger's tests. All statistical analyses were conducted by STATA version 10. Finally, fourteen studies were included in the meta-analysis. Both hydrophilic and hydrophobic statins showed no association with incidence of prostate cancer (RR = 1.00, 95% CI: 0.82-1.17; RR = 0.90, 95% CI: 0.73-1.08, respectively). Meanwhile, the risk of prostate cancer was not reduced in simvastatin (RR = 0.89, 95% CI: 0.72-1.05), pravastatin (RR = 1.02, 95% CI: 0.94-1.11), atorvastatin (RR = 0.89, 95% CI: 0.76-1.02), fluvastatin (RR = 0.99, 95% CI: 0.97-1.01), or lovastatin users (RR = 0.94, 95% CI: 0.79-1.08). The funnel plot showed that there was no publication bias. The results showed that statins had a neutral effect on prostate cancer risk; hydrophilic and hydrophobic statins as well as any subtype of statins did not affect the risk of prostate cancer.

Lipid pathway deregulation in advanced prostate cancer

The link between prostate cancer (PC) development and lipid metabolism is well established, with AR intimately involved in a number of lipogenic processes involving SREBP1, PPARG, FASN, ACC, ACLY and SCD1. Recently, there is growing evidence implicating the role of obesity and peri-prostatic adipose tissue (PPAT) in PC aggressiveness and related mortality, suggesting the importance of lipid pathways in both localised and disseminated disease. A number of promising agents are in development to target the lipogenic axis in PC, and the likelihood is that these agents will form part of combination drug strategies, with targeting of multiple metabolic pathways (e.g. FASN and CPT1), or in combination with AR pathway inhibitors (SCD1 and AR).

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.

High expression of SLCO2B1 is associated with prostate cancer recurrence after radical prostatectomy

Solute carrier organic anion (SLCO) gene families encode organic anion transport proteins, which are transporters that up-take a number of substrates including androgens. Among them, high expression of SLCO2B1 is known to associate with the resistance to androgen deprivation therapy in prostate cancer (PCa). We hypothesized that high expression of SLCO genes enhances PCa progression by promoting the influx of androgen. Here, we demonstrated the impact of the expression levels of SLCO2B1 on prognosis in localized PCa after radical prostatectomy (RP) utilizing 494 PCa cases in The Cancer Genome Atlas (TCGA). SLCO2B1 high expression group showed significantly worse Disease-free survival (DFS) after RP (p = 0.001). The expression level of SLCO2B1 was significantly higher in advanced characteristics including Gleason Score (GS ≤ 6 vs GS = 7; p = 0.047, GS = 7 vs GS ≥ 8; p = 0.002), pathological primary tumor (pT2 vs pT3/4; p < 0.001), and surgical margin status (positive vs negative; p = 0.013), respectively. There was a significant difference in DFS between these two groups only in GS ≥ 8 patients (p = 0.006). Multivariate analysis demonstrated that only SLCO2B1 expression level was an independent predictor for DFS after RP in GS ≥ 8. SLCO2B1 high expressed tumors in GS ≥ 8 not only enriched epithelial mesenchymal transition (EMT) related gene set, (p = 0.027), as well as Hedgehog (p < 0.001), IL-6/JAK/STAT3 (p < 0.001), and K-ras signaling gene sets (p < 0.001), which are known to promote EMT, but also showed higher expression of EMT related genes, including N-cadherin (p = 0.024), SNAIL (p = 0.001), SLUG (p = 0.001), ZEB-1 (p < 0.001) and Vimentin (p < 0.001). In conclusion, PCa with high expression of SLCO2B1 demonstrated worse DFS, which might be due to accelerated EMT.

Anti-Androgen Abiraterone Acetate Improves the Therapeutic Efficacy of Statins on Castration-Resistant Prostate Cancer Cells

The treatment of castration-resistant (CR) prostate cancer (PCa) is limited. A sub-population of CR PCa tumors can synthesize androgens for intracrine androgen receptor (AR) activation, thus targeting androgen biosynthesis could be an effective therapeutic option for these patients. We determined that androgen biosynthesis inhibitors simvastatin, atorvastatin, and ketoconazole directly inhibit growth, migration, and colony formation of LNCaP C-81 cells, which exhibit de novo androgen biosynthesis, with simvastatin being the most effective. Importantly, in combination treatments, statins specifically enhanced growth suppression with added effects by anti-androgen abiraterone acetate on the CR PCa cells. Thus, statins can be used in conjunction with abiraterone acetate to enhance anti-androgen therapy for CR PCa.

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.

Multicenter, Phase III, Randomized, Double-Blind, Placebo-Controlled Trial of Pravastatin Added to First-Line Standard Chemotherapy in Small-Cell Lung Cancer (LUNGSTAR)

Purpose Treating small-cell lung cancer (SCLC) remains a therapeutic challenge. Experimental studies show that statins exert additive effects with agents, such as cisplatin, to impair tumor growth, and observational studies suggest that statins combined with anticancer therapies delay relapse and prolong life in several cancer types. To our knowledge, we report the first large, randomized, placebo-controlled, double-blind trial of a statin with standard-of-care for patients with cancer, specifically SCLC. Patients and Methods Patients with confirmed SCLC (limited or extensive disease) and performance status 0 to 3 were randomly assigned to receive daily pravastatin 40 mg or placebo, combined with up to six cycles of etoposide plus cisplatin or carboplatin every 3 weeks, until disease progression or intolerable toxicity. Primary end point was overall survival (OS), and secondary end points were progression-free survival (PFS), response rate, and toxicity. Results Eight hundred forty-six patients from 91 United Kingdom hospitals were recruited. The median age of recruited patients was 64 years of age, 43% had limited disease, and 57% had extensive disease. There were 758 deaths and 787 PFS events. No benefit was found for pravastatin, either in all patients or in several subgroups. For pravastatin versus placebo, the 2-year OS rate was 13.2% (95% CI, 10.0 to 16.7) versus 14.1% (95% CI, 10.9 to 17.7), respectively, with a hazard ratio of 1.01 (95% CI, 0.88 to 1.16; P = .90. The median OS was 10.7 months v 10.6 months, respectively. The median PFS was 7.7 months v 7.3 months, respectively. The median OS (pravastatin v placebo) was 14.6 months in both groups for limited disease and 9.1 months versus 8.8 months, respectively, for extensive disease. Adverse events were similar between groups. Conclusion Pravastatin 40 mg combined with standard SCLC therapy, although safe, does not benefit patients. Our conclusions are the same as those found in all four much smaller, randomized, placebo-controlled trials specifically designed to evaluate statin therapy in patients with cancer.

Simvastatin Up-Regulates Annexin A10 That Can Inhibit the Proliferation, Migration, and Invasion in Androgen-Independent Human Prostate Cancer Cells

BACKGROUND

Statins have recently been studied for their proapoptotic and antimetastatic effects. However, the exact mechanisms of their anticancer actions remain unclear. Using microarrays, we discovered up-regulation of annexin A10 (ANXA10) in PC-3 cells after simvastatin treatment. ANXA10 reportedly has antitumor effects. In this study, we evaluated the effects of simvastatin on ANXA10 signaling in androgen-independent prostate cancer cells.

METHODS

PC-3, LNCaP-LA (which were derived from LNCaP cells and cultured in 10% charcoal-stripped fetal bovine serum for 3 months), and DU145 human prostate cancer cell lines were used. Prostate tissues were collected from 60 patients (benign prostatic hyperplasia [BPH], n = 20; prostate cancer with a Gleason score of 7, n = 20; prostate cancer with a Gleason score of 8-10, n = 20) at the time of prostate biopsies performed. We used a nude mouse tumor xenograft model with administration of simvastatin or phosphate-buffered saline via intraperitoneal injection.

RESULTS

Simvastatin inhibited the proliferation, migration, and invasion of PC-3, LNCaP-LA, and DU145 cells. The expression level of ANXA10 was up-regulated by simvastatin in PC-3, LNCaP-LA, and DU145 cells. Transfection with ANXA10 inhibited PC-3 and LNCaP-LA cells proliferation, migration, and invasion. Knockdown of ANXA10 by siRNA increased the proliferation of PC-3 and LNCaP-LA cells. In a nude mouse xenograft model of PC-3 cells, simvastatin induced both reduction in the tumor size and up-regulation of ANXA10 expression. In human prostate biopsy samples, ANXA10 mRNA expression was significantly lower in the prostate cancer group than in the BPH group. Next, we found that up-regulation of ANXA10 in PC-3 resulted in down-regulation of S100 calcium binding protein A4 (S100A4), which is reportedly correlated with aggressiveness and a worse prognosis for patients with different types of carcinomas. Expression of S100A4 was down-regulated by simvastatin. In PC-3 cells, knockdown of S100A4 by siRNA inhibited the proliferation, migration, and invasion of PC-3 cells.

CONCLUSION

Our results suggest that statins inhibit the proliferation, migration, and invasion of androgen-independent prostate cancer cells by up-regulation of ANXA10. Additionally, it is possible that S100A4 plays a role in these effects. Statins may be beneficial in the prevention and/or treatment of prostate cancer. Prostate 77: 337-349, 2017. © 2016 Wiley Periodicals, Inc.

Metformin as an adjuvant treatment for cancer: a systematic review and meta-analysis

BACKGROUND

Metformin use has been associated with a reduced risk of developing cancer and an improvement in overall cancer survival rates in meta-analyses, but, to date, evidence to support the use of metformin as an adjuvant therapy in individual cancer types has not been presented.

PATIENTS AND METHODS

We systematically searched research databases, conference abstracts and trial registries for any studies reporting cancer outcomes for individual tumour types in metformin users compared with non-users, and extracted data on patients with early-stage cancer. Studies were assessed for design and quality, and a meta-analysis was conducted to quantify the adjuvant effect of metformin on recurrence-free survival (RFS), overall survival (OS) and cancer-specific survival (CSS), to inform future trial design.

RESULTS

Of 7670 articles screened, 27 eligible studies were identified comprising 24 178 participants, all enrolled in observational studies. In those with early-stage colorectal cancer, metformin use was associated with a significant benefit in all outcomes [RFS hazard ratio (HR) 0.63, 95% confidence interval (CI) 0.47-0.85; OS HR 0.69, CI 0.58-0.83; CSS HR 0.58, CI 0.39-0.86]. For men with early-stage prostate cancer, metformin was associated with significant, or borderline significant, benefits in all outcomes (RFS HR 0.83, CI 0.69-1.00; OS HR 0.82, CI 0.73-0.93; CSS HR 0.58, CI 0.37-0.93); however, there was significant heterogeneity between studies. The data suggest that prostate cancer patients treated with radical radiotherapy may benefit more from metformin (RFS HR 0.45, CI 0.29-0.70). In breast and urothelial cancer, no significant benefits were identified. Sufficient data were not available to conduct analyses on the impact of metformin dose and duration.

CONCLUSIONS

Our findings suggest that metformin could be a useful adjuvant agent, with the greatest benefits seen in colorectal and prostate cancer, particularly in those receiving radical radiotherapy, and randomised, controlled trials which investigate dose and duration, alongside efficacy, are advocated.

The current evidence on statin use and prostate cancer prevention: are we there yet?

An increasing amount of data supports an inverse association between statin use and cancer risk. The findings for prostate cancer, particularly advanced disease, are the most promising of all cancers studied. Use of these agents seems to also be associated with improved prostate- cancer-specific survival, particularly in men undergoing radiotherapy, suggesting usefulness of statins in secondary and tertiary prevention. Some study results might be influenced by increased PSA screening and health-conscious behaviour in statin users but these factors are unlikely to completely account for observed beneficial effects. The epidemiological evidence is supported by preclinical studies that show that statins directly inhibit prostate cancer development and progression in cell-based and animal-based models. The antineoplastic effect of statins might arise from a number of cholesterol-mediated and non-cholesterol-mediated mechanisms that affect pathways essential for cancer formation and progression. Understanding these mechanisms is instrumental in drug discovery research for the development of future prostate cancer therapeutics, as well as in designing clinical trials to test a role for statins in prostate cancer prevention. Currently, sufficient data are lacking to support the use of statins for the primary prevention of prostate cancer and further research is clearly warranted. Secondary and tertiary prevention trials in men who have been diagnosed with prostate cancer might soon be performed.

Metabolic profiling of cholesterol and sex steroid hormones to monitor urological diseases

Cholesterol and sex steroid hormones including androgens and estrogens play a critical role in the development and progression of urological diseases such as prostate cancer. This disease remains the most commonly diagnosed malignant tumor in men and is the leading cause of death from different cancers. Attempts to understand the role of cholesterol and steroid metabolism in urological diseases have been ongoing for many years, but despite this, our mechanistic and translational understanding remains elusive. In order to further evaluate the problem, we have taken an interest in metabolomics; a discipline dedicated to the systematic study of biologically active metabolites in cells, tissues, hair and biofluids. Recently, we provided evidence that a quantitative measurement of cholesterol and sex steroid metabolites can be successfully achieved using hair of human and mouse models. The overall goal of this short review article is to introduce current metabolomic technologies for the quantitative biomarker assay development and also to provide new insight into understanding the underlying mechanisms that trigger the pathological condition. Furthermore, this review will place a particular emphasis on how to prepare biospecimens (e.g., hair fiber), quantify molecular profiles and assess their clinical significance in various urological diseases.

Statin derivatives as therapeutic agents for castration-resistant prostate cancer

Despite recent advances in modern medicine, castration-resistant prostate cancer remains an incurable disease. Subpopulations of prostate cancer cells develop castration-resistance by obtaining the complete steroidogenic ability to synthesize androgens from cholesterol. Statin derivatives, such as simvastatin, inhibit cholesterol biosynthesis and may reduce prostate cancer incidence as well as progression to advanced, metastatic phenotype. In this study, we demonstrate novel simvastatin-related molecules SVA, AM1, and AM2 suppress the tumorigenicity of prostate cancer cell lines including androgen receptor-positive LNCaP C-81 and VCaP as well as androgen receptor-negative PC-3 and DU145. This is achieved through inhibition of cell proliferation, colony formation, and migration as well as induction of S-phase cell-cycle arrest and apoptosis. While the compounds effectively block androgen receptor signaling, their mechanism of inhibition also includes suppression of the AKT pathway, in part, through disruption of the plasma membrane. SVA also possess an added effect on cell growth inhibition when combined with docetaxel. In summary, of the compounds studied, SVA is the most potent inhibitor of prostate cancer cell tumorigenicity, demonstrating its potential as a promising therapeutic agent for castration-resistant prostate cancer.

Influence of Statins on Survival Outcome in Patients with Metastatic Castration Resistant Prostate Cancer Treated with Abiraterone Acetate

OBJECTIVE

Even though the exact mechanism is largely unknown until now, statins are supposed to improve survival outcomes in various malignancies. For prostate cancer however, statins are known to compete with dehydroepiandrosterone (DHEAS) for the transport into the cytosol both using the cell by the Solute Carrier Transporter and thus diminish the cellular uptake of DHEAS as a precursor of androgens. Abiraterone inhibits CYP17A1 and thus effectively decreases the production of all relevant androgens including DHEAS. In this study we examined whether statins still affect survival outcome in patients with metastatic castration resistant prostate cancer (mCRPC) when treated with Abiraterone.

PATIENTS AND METHODS

108 men with mCRPC treated with Abiraterone from 02/2010 to 07/2015 with (n = 21) or without (n = 87) concomitant treatment with statins were investigated. Progression free survival (PFS) and overall survival (OS) were analyzed using Kaplan-Meier-estimates and univariate Cox-regression analysis. The influence on best clinical benefit under Abiraterone treatment was analyzed with bivariate and multivariate logistic regression analysis.

RESULTS

PSA-decline ≥ 50% was not significantly different in both groups (57 vs. 53%; p = 0.73). The median PFS (9 vs. 10 months; p = 0.97) and OS (14 vs. 18 months; p = 0.77) did not differ significantly between those men treated with and without concomitant statin therapy, respectively. Accordingly, there was no improvement for best clinical benefit in patients using statins (odds ratio: 1.2 (CI: 0.4-4.2); p = 0.76).

CONCLUSION

Use of statins as concomitant medication did not improve survival outcomes or best clinical benefit in men with mCRPC treated with Abiraterone.

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.

Impact of statin use on cancer recurrence and mortality in breast cancer: A systematic review and meta-analysis

Statins have shown antineoplastic properties in preclinical studies with breast cancer cells. They inhibit the enzyme "HMG CoA reductase" and the expression of this enzyme in cancer cells has been implicated as a favorable prognostic factor in patients with breast cancer. After a search of MEDLINE and Embase from inception through November 2015, 817 abstracts were reviewed to identify studies that described an association between statin use and outcomes in breast cancer. A total of 14 studies which included 75,684 women were identified. In a meta-analysis of 10 studies, statin use was associated with improved recurrence-free survival (RFS; HR 0.64; 95% CI 0.53-0.79, I(2)  = 44%). Furthermore, this RFS benefit appeared to be confined to use of lipophilic statins (HR 0.72; 95% CI 0.59-0.89) as hydrophilic statin use was not associated with improvement in RFS (HR 0.80; 95% CI 0.44-1.46). Statin users similarly showed improved overall survival in a meta-analysis with substantial heterogeneity (8 studies, HR 0.66; 95% CI 0.44-0.99, I(2)  = 89%). Statin users also had improved cancer-specific survival, although this relationship was measured with less precision (six studies, HR 0.70; 95% CI 0.46-1.06, I(2)  = 86%). In conclusion, breast cancer patients who use statins, or specifically, lipophilic statins show improved recurrence-free survival. Statin users also had improved overall survival and cancer-specific survival. These findings should be assessed in a prospective randomized cohort and the choice of statin, dose and biomarkers that may predict the efficacy of these drugs should be identified.

Statin Use at the Time of Initiation of Androgen Deprivation Therapy and Time to Progression in Patients With Hormone-Sensitive Prostate Cancer

IMPORTANCE

Statin use has been associated with improved prostate cancer outcomes. Dehydroepiandrosterone sulfate (DHEAS) is a precursor of testosterone and a substrate for SLCO2B1, an organic anionic transporter. We previously demonstrated that genetic variants of SLCO2B1 correlated with time to progression (TTP) during receipt of androgen deprivation therapy (ADT). Statins also use SLCO2B1 to enter cells, and thus we hypothesized that they may compete with DHEAS uptake by the tumor cells.

OBJECTIVE

To evaluate whether statin use prolongs TTP during ADT for hormone-sensitive prostate cancer.

DESIGN, SETTING, AND PARTICIPANTS

In vitro studies were performed using prostate cancer cell lines at an academic, comprehensive cancer center. Statin use was retrospectively analyzed in 926 patients who had received ADT for biochemical or metastatic recurrence or de novo metastatic prostate cancer between January 1996 and November 2013.

MAIN OUTCOMES AND MEASURES

To determine whether statins interfere with DHEAS uptake, we performed in vitro studies using prostate cancer cell lines. Next, we queried our institutional clinical database to assess for an association between statin use and TTP during ADT using multivariable Cox regression analysis and adjusted for known prognostic factors.

RESULTS

In vitro, we demonstrated that statins block DHEAS uptake by competitively binding to SLCO2B1. In our ADT cohort of 926 patients, 283 (31%) were taking a statin at ADT initiation. After a median follow-up of 5.8 years, 644 patients (70%) had experienced disease progression while receiving ADT. Median TTP during ADT was 20.3 months (95% CI, 18-24 months). Men taking statins had a longer median TTP during ADT compared with nonusers (27.5 [95% CI, 21.1-37.7] vs 17.4 [95% CI, 14.9-21.1] months; P < .001). The association remained statistically significant after adjusting for predefined prognostic factors (adjusted hazard ratio, 0.83 [95% CI, 0.69-0.99]; P = .04). The positive statin effect was observed for both patients with and without metastases (adjusted hazard ratio, 0.79 [95% CI, 0.58-1.07] for M0 disease and 0.84 [95% CI, 0.67-1.06] for M1 disease; P for interaction = .72).

CONCLUSIONS AND RELEVANCE

Statin use at the time of ADT initiation was associated with a significantly longer TTP during ADT even after adjustment for known prognostic factors. Our in vitro finding that statins competitively reduce DHEAS uptake, thus effectively decreasing the available intratumoral androgen pool, affords a plausible mechanism to support the clinical observation of prolonged TTP in statin users.