Effects of statins on the prognosis of local and locally advanced renal cell carcinoma following nephrectomy

Effect of smoking, hypertension and lifestyle factors on kidney cancer - perspectives for prevention and screening programmes

Renal cell carcinoma (RCC) incidence has doubled over the past few decades. However, death rates have remained stable as the number of incidental renal mass diagnoses peaked. RCC has been recognized as a European health care issue, but to date, no screening programmes have been introduced. Well-known modifiable risk factors for RCC are smoking, obesity and hypertension. A direct association between cigarette consumption and increased RCC incidence and RCC-related death has been reported, but the underlying mechanistic pathways for this association are still unclear. Obesity is associated with an increased risk of RCC, but interestingly, improved survival outcomes have been reported in obese patients, a phenomenon known as the obesity paradox. Data on the association between other modifiable risk factors such as diet, dyslipidaemia and physical activity with RCC incidence are conflicting, and potential mechanisms underlying these associations remain to be elucidated.

Influence of statin use on prognosis of patients with renal cell cancer: a meta-analysis

Background

Statin may confer anticancer efficacy, while the studies evaluating the influence of statin on survival of patients with renal cell cancer (RCC) yielded inconsistent results. A systematic review and meta-analysis was performed to investigate the association between statin use and survival of patients with RCC.

Materials and Methods

Cohort studies were identified by search of PubMed, Embase, and Web of Science databases according to the objective of the meta-analysis. A random-effect model incorporating the possible between-study heterogeneity was used for meta-analysis. Subgroup analyses according to study characteristics were also performed.

Results

Seventeen cohort studies involving 42528 patients with RCC were available for the meta-analysis. Results showed that statin use was associated with a better overall survival (OS, hazard ratio [HR]: 0.73, 95% confidence interval [CI]: 0.65 to 0.84, p < 0.001; I² = 40%), progression progression-free survival (PFS, HR: 0.82, 95% CI: 0.68 to 0.98, p = 0.03; I² = 52%), and cancer-specific survival (CSS, HR: 0.76, 95% CI: 0.59 to 0.99, p = 0.04; I² = 38%). Besides, for the outcome of OS and PFS, subgroup analyses showed similar results in patients with surgical and non-surgical anticancer treatments, and in patients with stage I-III and stage IV RCC (p values for subgroup difference all > 0.05).

Conclusions

Statin use may be associated with improved survival outcomes in patients with RCC. Although prospective clinical studies should be considered to validate these results, these findings suggest that statins may be potential adjuvant therapy for patients with RCC.

Beyond Lipid-Lowering: Effects of Statins on Cardiovascular and Cerebrovascular Diseases and Cancer

The 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase inhibitors, also known as statins, are administered as first-line therapy for hypercholesterolemia, both as primary and secondary prevention. Besides the lipid-lowering effect, statins have been suggested to inhibit the development of cardiovascular disease through anti-inflammatory, antioxidant, vascular endothelial function-improving, plaque-stabilizing, and platelet aggregation-inhibiting effects. The preventive effect of statins on atherothrombotic stroke has been well established, but statins can influence other cerebrovascular diseases. This suggests that statins have many neuroprotective effects in addition to lowering cholesterol. Furthermore, research suggests that statins cause pro-apoptotic, growth-inhibitory, and pro-differentiation effects in various malignancies. Preclinical and clinical evidence suggests that statins inhibit tumor growth and induce apoptosis in specific cancer cell types. The pleiotropic effects of statins on cardiovascular and cerebrovascular diseases have been well established; however, the effects of statins on cancer patients have not been fully elucidated and are still controversial. This review discusses the recent evidence on the effects of statins on cardiovascular and cerebrovascular diseases and cancer. Additionally, this study describes the pharmacological action of statins, focusing on the aspect of ‘beyond lipid-lowering’.

Targeting the Mevalonate Pathway Suppresses VHL-Deficient CC-RCC through an HIF-Dependent Mechanism

Clear cell renal cell carcinoma (CC-RCC) is a devastating disease with limited therapeutic options available for advanced stages. The objective of this study was to investigate HMG-CoA reductase inhibitors, also known as statins, as potential therapeutics for CC-RCC. Importantly, treatment with statins was found to be synthetically lethal with the loss of the von Hippel-Lindau (VHL) tumor suppressor gene, which occurs in 90% of CC-RCC driving the disease. This effect has been confirmed in three different CC-RCC cell lines with three different lipophilic statins. Inhibition of mevalonate synthesis by statins causes a profound cytostatic effect at nanomolar concentrations and becomes cytotoxic at low micromolar concentrations in VHL-deficient CC-RCC. The synthetic lethal effect can be fully rescued by both mevalonate and geranylgeranylpyrophosphate, but not by squalene, indicating that the effect is due to disruption of small GTPase isoprenylation and not the inhibition of cholesterol synthesis. Inhibition of Rho and Rho kinase (ROCK) signaling contributes to the synthetic lethality effect, and overactivation of hypoxia-inducible factor signaling resulting from VHL loss is required. Finally, statin treatment is able to inhibit both tumor initiation and progression of subcutaneous 786-OT1-based CC-RCC tumors in mice. Thus, statins represent potential therapeutics for the treatment of VHL-deficient CC-RCC. Mol Cancer Ther; 17(8); 1781-92. ©2018 AACR.

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.

Statin use and kidney cancer survival outcomes: A systematic review and meta-analysis

BACKGROUND

Statin use has been associated with improved survival outcomes in various malignancies. Randomized controlled trials are currently underway evaluating their utility as adjunctive cancer therapies. However, studies evaluating the association between statin use and outcomes in kidney cancer yield conflicting results.

METHODS

We searched MEDLINE and EMBASE to identify studies evaluating the association between statin use and kidney cancer survival outcomes. We evaluated risk of bias with the Newcastle-Ottawa Scale. We pooled hazard ratios for recurrence-free survival, progression-free survival, cancer-specific survival, and overall survival using random-effects models. We evaluated publication bias through Begg's and Egger's tests, and the trim and fill procedure.

RESULTS

We identified 12 studies meeting inclusion criteria and summarized data from 18,105 patients. No study was considered to be at high risk of bias. Statin use was not significantly associated with recurrence-free survival (pooled HR 0.97, 95% CI 0.89-1.06) or progression-free survival (pooled HR 0.92, 95% CI 0.51-1.65); however, statin use was associated with marked improvements in cancer-specific survival (pooled HR 0.67, 95% CI 0.47-0.94) and overall survival (pooled HR 0.74, 95% CI 0.63-0.88). There was no strong evidence of publication bias for any outcome.

CONCLUSIONS

Our results demonstrate that statin use among patients with kidney cancer is associated with significantly improved cancer-specific and overall survival. Further studies are needed to confirm the therapeutic role of statins in kidney cancer.

The Prognostic Effect of Statin Use on Urologic Cancers: An Updated Meta-Analysis of 35 Observational Studies

Recent studies suggest that statin may benefit cancer prognosis, especially through its radiosensitization effect. But controversy exists in other studies. Hence, we performed a meta-analysis of results from 35 studies to evaluate the effect of statin use on urologic cancers.We conducted computerized search from PubMed, Embase, and ISI Web of Knowledge through May 2015, screened the retrieved references, and collected and evaluated relevant information. We extracted and synthesized corresponding hazard ratios (HR) and confidence interval (CI) by using Review Manager 5.3 and STATA 13. This review was registered at PROSPERO with registration No. CRD42015020171.We selected total 35 retrospective studies and conducted a meta-analysis of results from these studies. The pooled results suggested no benefit of statin use to bladder cancer and renal cell carcinoma, except overall survival [HR = 0.81, 95% CI: 0.69-0.96]. However, significant improvement of prostate cancer prognosis including overall survival [HR = 0.82, 95% CI: 0.70-0.97] and cancer-specific survival [HR = 0.70, 95% CI: 0.59-0.83] was indicated, but not including tumor progression [HR = 0.84, 95% CI: 0.62-1.14]. Statin use improved biochemical recurrence of prostate cancer in radiotherapy patients [HR = 0.68, 95% CI: 0.54-0.85] but not in radical prostatectomy patients [HR = 0.97, 95% CI: 0.82-1.15].Current evidence suggests no benefit of statin use to bladder cancer and renal cell carcinoma, except in overall survival. While statin use benefited prostate cancer patients in overall survival, cancer-specific survival but not in tumor progression; it also improved biochemical recurrence in radiotherapy patients but not in radical patients. To verify these results, randomized controlled trials are necessary.

Statins: do they have a potential role in cancer prevention and modifying cancer-related outcomes?

3-Hydroxy-3-methylglutaryl-coenzyme A reductase inhibitors (statins) are currently among the most commonly prescribed pharmaceutical agents worldwide. Apart from their well-established therapeutic value in cardiovascular disease, there is a long-standing debate on their potential association with cancer. To obtain and discuss the existing clinical evidence, an overview of meta-analysis articles addressing this issue was carried out. As of today, the accumulated evidence does not support the hypothesis that statins affect the risk of developing cancer, when they are taken at low doses for managing hypercholesterolaemia. However, current data cannot exclude an increased cancer risk in elderly patients associated with hydrophilic statin use, or decreases in the risks of certain cancers, such as gastric, oesophageal, liver, colorectal and advanced/aggressive prostate cancer. On the other hand, some recent observational studies have provided evidence that statins might be useful in modifying the prognosis of patients diagnosed with malignancy. Until a definitive benefit is demonstrated in randomized controlled trials, statins cannot be recommended either for cancer prevention or for modifying cancer-related outcomes. Further research is warranted to clarify the potential role(s) of statins in the prevention and treatment of cancer.

The Impact of Diabetes Mellitus on Renal Cell Carcinoma Prognosis: A Meta-Analysis of Cohort Studies

Previous studies that investigated the relationship between DM and survival in renal cell carcinoma (RCC) patients reported inconsistent findings. Hence, we conducted a meta-analysis to obtain a more precise evaluation of the prognostic significance of DM in RCC. A systematic review was conducted with PubMed, Embase, and Web of Science to identify relevant articles that evaluated the effect of DM on RCC patients. Based on the inclusion and quality assessment criteria, 18 studies were eligible for the meta-analysis. Pooled hazard ratios (HR) and corresponding 95% confidence intervals (CI) for overall survival (OS), cancer-specific survival (CSS), and recurrence-free survival (RFS) were calculated by standard meta-analysis techniques. The results suggested that DM was associated with poor OS (HR 1.56, 95% CI, 1.35-1.81, P < 0.001), poor CSS (HR 2.03, 95% CI, 1.37-3.01, P < 0.001), and poor RFS (HR 1.73, 95% CI, 1.25-2.39, P = 0.012). In addition, for patients with localized RCC, patients with clear cell RCC, or patients receiving nephrectomy, DM was associated with both poor OS and CSS by subgroup analyses. Our study revealed that there was a significant negative impact of DM on OS, CSS, and RFS in RCC patients. Therefore, more attention should be paid to RCC patients with preexisting DM because of their poor prognosis.

Relationship between the use of statins and patient survival in colorectal cancer: a systematic review and meta-analysis

Background

Studies have indicated that statins influence the risks and mortality rates of several types of solid tumors. However, the association between statin use and survival in patients with colorectal cancer (CRC) remains unclear.

Methods

We searched the PubMed and Embase databases for relevant studies published up to September 2014 that assessed statin use and CRC prognosis. The primary outcomes were overall survival (OS) and cancer-specific survival (CSS). The secondary outcomes were disease-free survival (DFS) and recurrence-free survival (RFS). Hazard ratios (HRs) and 95% confidence intervals (CIs) were extracted and pooled with Mantel–Haenszel random-effect modeling. All statistical tests were two-sided.

Results

Four studies on post-diagnosis statin therapy and five studies on pre-diagnosis statin use were included in our meta-analysis of 70,608 patients. Compared with the non-users, the patients with post-diagnosis statin use gained survival benefits for OS (HR 0.76; 95% CI: 0.68 to 0.85, P<0.001) and CSS (HR 0.70; 95% CI: 0.60 to 0.81, P<0.001). In addition, we observed that pre-diagnosis statin use prolonged the survival of patients with CRC for OS (HR 0.70; 95% CI: 0.54 to 0.91, P=0.007) and CSS (HR 0.80; 95% CI: 0.74 to 0.86, P<0.001). However, we did not observe a survival benefit for DFS (HR 1.13; 95% CI: 0.78 to 1.62, P=0.514) or RFS (HR 0.98; 95% CI: 0.36 to 2.70, P=0.975) in the CRC patients with post-diagnosis statin use.

Conclusions

Statin use before or after cancer diagnosis is related to reductions in overall and cancer-specific mortality in colorectal cancer survivors.