Statins in oncological research: from experimental studies to clinical practice. Crit Rev Oncol Hematol. 2014;92:296-311. [PMID: 25220658 DOI: 10.1016/j.critrevonc.2014.08.002]

Exposome and basal cell carcinoma: a multicenter case-control study

BACKGROUND

While ultraviolet radiation (UVR) present in sunlight is recognized as the main etiological agent of skin cancer, the most frequent form of which is basal cell carcinoma (BCC), other exposome factors like pollution, diet, and lifestyle may also contribute. This study aimed to investigate the association of BCC and exposome-related factors in the Spanish population.

METHODS

BCC cases (n = 119) and controls (n = 127) with no history of skin cancer were recruited between April 2020 and August 2022 by 13 dermatologists throughout Spain in this prospective multicenter case-control study.

RESULTS

The BCC group had a higher proportion of outdoor workers, more years of UVR exposure, and a greater consumption of drugs (statins, ASA, hydrochlorothiazide, ACE inhibitors and omeprazole), P < 0.05. Avoidance of sun exposure was the most used photoprotection measure in both groups. The use of hats or caps was higher in the BCC group (P = 0.01). The solar protection factor (SPF) used 15 years previously was higher in the control group (P = 0.04). The control group had a higher daily screen time (P < 0.001), and practiced more relaxation activities (P = 0.03). Higher linolenic acid intake and lower coffee consumption were the only dietary variables associated with BCC (P < 0.05). Statistical significance for all the aforementioned variables was maintained in the multivariate analysis (P < 0.05).

CONCLUSIONS

The study found a significant association between BCC and multiple exposome-related factors in addition to chronic sun exposure in the Spanish population. Primary prevention strategies should target specific populations, such as outdoor workers, promoting sun-safe behaviors and stress-reducing activities, and also adequate skin photoprotection in patients on certain medications associated with increased BCC risk.

Effect of Statin Lipophilicity on the Proliferation of Hepatocellular Carcinoma Cells

The HMG-CoA reductase inhibitors, statins, are drugs used globally for lowering the level of cholesterol in the blood. Different clinical studies of statins in cancer patients have indicated a decrease in cancer mortality, particularly in patients using lipophilic statins compared to those on hydrophilic statins. In this paper, we selected two structurally different statins (simvastatin and pravastatin) with different lipophilicities and investigated their effects on the proliferation and apoptosis of hepatocellular carcinoma cells. Lipophilic simvastatin highly influences cancer cell growth and survival in a time- and concentration-dependent manner, while pravastatin, due to its hydrophilic structure and limited cellular uptake, showed minimal cytotoxic effects.

The Influence of the Exposome in the Cutaneous Squamous Cell Carcinoma, a Multicenter Case-Control Study

INTRODUCTION

The concept of exposome refers to the total of harmful and beneficial environmental exposures that can help predict the organism's biological responses over time. Ultraviolet radiation (UVR) from sun exposure has been recognized as the main etiological agent of skin cancer, and squamous cell carcinoma (SCC) is one most commonly associated with chronic exposure. However, in recent years, evidence suggests that lifestyle, environmental pollution, and contaminants in water and food can have an influence.

OBJECTIVES

To study the relationship between SCC and sun exposure, pollution, stress, and lifestyle in a Spanish cohort.

MATERIALS AND METHOD

A multicenter case-control study was carried out in which 13 dermatologists from different regions of Spain recruited cases and controls between April 2020 and August 2022. The group of cases were patients diagnosed with SCC and, as a control group, people who attended Dermatology consultations as companions with no history of skin cancer.

RESULTS

A total of 62 patients with SCC and 126 controls were included (62.9% males, median age 76.46 (10.1) and 33.3%, median age 55.7 (15), respectively). The SCC group had experienced more outside work than the controls (75% vs. 22.4%, p < 0.001), less recreational exposure (sunbathing, p = 0.05, and outdoor sports, p = 0.01), and a lower annual income (p = 0.01), with an increase in tobacco exposure (p < 0.001), without differences in other carcinogens, such as ionizing radiation or chemical exposure. The control group had a higher daily screentime use (p < 0.001) and practiced more relaxation activities (p = 0.03). A higher linolenic acid intake and lower coffee consumption were the only dietary variables associated with SCC (p < 0.05). Some chronic medications (anxiolytics, antidepressants, beta-blockers, statins, hydrochlorothiazide, ACE inhibitors, metformin, and omeprazole) were also statistically associated with SCC. Statistical significance for all aforementioned variables was maintained in the multivariate analysis (p < 0.05).

CONCLUSIONS

The study found a significant association between SCC and multiple exposome-related factors in addition to chronic sun exposure in the Spanish population. Primary prevention strategies should target specific populations, such as outdoor workers promoting sun-safe behaviors and stress-reducing activities, in addition to adequate skin photoprotection in patients under certain medications associated with SCC.

Statin Use and Skin Cancer Risk: A Prospective Cohort Study

Epidemiological studies on statin use in relation to skin cancer risk are scarce and yielded conflicting results. We explored this association in Etude Epidémiologique auprès de femmes de l'Education Nationale, a prospective cohort of French women born in 1925-1950. Health and lifestyle data were self-reported biennially and matched with drug reimbursement data, allowing the identification of participants' statin use since 2004. Multivariable cause-specific hazards regression models adjusted for skin cancer risk factors estimated hazard ratios with 95% confidence intervals. Over 2004-2014, 455 cutaneous melanoma, 1,741 basal cell carcinoma, and 268 squamous cell carcinoma cases were ascertained among 62,473 women. Compared with never use, there were no associations between ever use of statins and melanoma (hazard ratio = 1.16, 95% confidence interval = 0.94-1.44) or squamous cell carcinoma (hazard ratio = 0.89, 95% confidence interval = 0.66-1.19) risks and a decrease in basal cell carcinoma risk with ever use of statins (hazard ratio = 0.89, 95% confidence interval = 0.79-0.996). We found no trend of increasing or decreasing risks with dose, duration of use, time since first use, or age at first use and no statistically significant effect modification by pigmentary traits or residential UVR exposure. Because of the limited number of studies evaluating the associations between the use of statins and the risks of melanoma, basal cell carcinoma, and squamous cell carcinoma, these findings would deserve further investigation in other settings.

Statins: a repurposed drug to fight cancer

As competitive HMG-CoA reductase (HMGCR) inhibitors, statins not only reduce cholesterol and improve cardiovascular risk, but also exhibit pleiotropic effects that are independent of their lipid-lowering effects. Among them, the anti-cancer properties of statins have attracted much attention and indicated the potential of statins as repurposed drugs for the treatment of cancer. A large number of clinical and epidemiological studies have described the anticancer properties of statins, but the evidence for anticancer effectiveness of statins is inconsistent. It may be that certain molecular subtypes of cancer are more vulnerable to statin therapy than others. Whether statins have clinical anticancer effects is still an active area of research. Statins appear to enhance the efficacy and address the shortcomings associated with conventional cancer treatments, suggesting that statins should be considered in the context of combined therapies for cancer. Here, we present a comprehensive review of the potential of statins in anti-cancer treatments. We discuss the current understanding of the mechanisms underlying the anti-cancer properties of statins and their effects on different malignancies. We also provide recommendations for the design of future well-designed clinical trials of the anti-cancer efficacy of statins.

Statins and immunotherapy: Togetherness makes strength The potential effect of statins on immunotherapy for NSCLC

Background

Recent researches suggested that statins, beside their role in inhibiting endogenous cholesterol synthesis and in cardiovascular prevention, could influence several processes in cancer biology. In fact, a recent meta‐analysis demonstrated that statins could positively influence OS in lung cancer patients.

Aim

There is a lack of large cohort studies that could support a potential antineoplastic role of statins in clinical practice. We collected data from 162 patients treated with immunotherapy for Nonsmall Cell Lung Cancer (NSCLC) in first‐ and second‐line setting to investigate the impact of these drugs on survival parameters.

Methods and Results

In our observational study, we enrolled 162 patients who received immunotherapy for lung cancer between October 2015 and April 2020. We used descriptive statistics to analyze patients' baseline features. Tumor response was evaluated using RECIST version 1.1 guidelines. Uni and multivariate analysis were conducted to investigate the relationship between statin use and response to immunotherapy, using the χ²‐test. We used Kaplan‐Meier curves to estimate OS and PFS in statin and nonstatin users. We included 122 patients in the final analysis. Median PFS was 17.57 months in the statin group and 9.57 months in the nonstatin group, with a P = <.001. Moreover, median OS was superior in the statin‐users group, with a statistically significant difference (19.94 vs 10.94 months, P = <.001).

Conclusion

Although in our study, statin use positively correlates with PFS and OS in lung cancer patient treated with immunotherapy, these results require a further validation with randomized clinical trials.

Pleiotropic effects of statins: A focus on cancer

The statin drugs ('statins') potently inhibit hydroxymethylglutaryl-coenzyme A (HMG-CoA) reductase by competitively blocking the active site of the enzyme. Statins decrease de novo cholesterol biosynthesis and thereby reduce plasma cholesterol levels. Statins exhibit "pleiotropic" properties that are independent of their lipid-lowering effects. For example, preclinical evidence suggests that statins inhibit tumor growth and induce apoptosis in specific cancer cell types. Furthermore, statins show chemo-sensitizing effects by impairing Ras family GTPase signaling. However, whether statins have clinically meaningful anti-cancer effects remains an area of active investigation. Both preclinical and clinical studies on the potential mechanisms of action of statins in several cancers have been reviewed in the literature. Considering the contradictory data on their efficacy, we present an up-to-date summary of the pleiotropic effects of statins in cancer therapy and review their impact on different malignancies. We also discuss the synergistic anti-cancer effects of statins when combined with other more conventional anti-cancer drugs to highlight areas of potential therapeutic development.

Targeting Lipid Metabolism in Liver Cancer

Cancer cells are highly dependent on different metabolic pathways for sustaining their survival, growth, and proliferation. Lipid metabolism not only provides the energetic needs of the cells but also provides the raw material for cellular growth and the signaling molecules for many oncogenic pathways. Mainly processed in the liver, lipids play an essential role in the physiology of this organ and in the pathological progression of many diseases such as metabolic syndrome and hepatocellular carcinoma (HCC). The progression of HCC is associated with inflammation and complex metabolic reprogramming, and its prognosis remains poor because of the lack of effective therapies despite many years of dedicated research. Defects in hepatic lipid metabolism induce abnormal gene expression and rewire many cellular pathways involved in oncogenesis and metastasis, implying that interfering with lipid metabolism within the tumor and the surrounding microenvironment may be a novel therapeutic approach for treating liver cancer patients. Therefore, this review focuses on the latest advances in drugs targeting lipid metabolism and leading to promising outcomes in preclinical studies and some ongoing clinical trials.

Association of Aspirin, Metformin, and Statin Use with Gastric Cancer Incidence and Mortality: A Nationwide Cohort Study

Anticancer effects of aspirin, metformin, and statins against gastric cancer, one of the most common cancers in the world, have been reported. This retrospective cohort study aimed to investigate independent associations of aspirin, metformin, and statin use with gastric cancer incidence and mortality after adjustment for concomitant use of other drugs, using pooled cohort data extracted from the Korean National Health Insurance claim database. Follow-up started on January 1, 2004 and ended at the date of gastric cancer diagnosis, death, or December 31, 2013. Exposures to drugs were defined as cumulative duration of use for aspirin and cumulative defined daily dose for metformin and statin, and were entered as time-dependent variables in Cox analysis models to avoid immortal time bias. Use of aspirin for longer than 182.5 and 547.5 days during 2-year interval was associated with reduced risks of gastric cancer incidence and mortality, respectively. Patients with diabetes were at higher risk of gastric cancer incidence and mortality than nondiabetic people, regardless of metformin treatment. However, metformin use among patients with diabetes was associated with a reduction in gastric cancer mortality in a dose-response manner. Statin use was also associated with a reduction of gastric cancer mortality in the general population, but not with gastric cancer incidence. In conclusion, long-term use of aspirin was independently associated with reduced incidence and mortality of gastric cancer in the general population, but metformin or statin use was only associated with a reduction of gastric cancer mortality in patients with diabetes and in the general population, respectively. PREVENTION RELEVANCE: Long-term use of aspirin was independently associated with reduced incidence and mortality of gastric cancer in the general population. Metformin or statin use, however, was only associated with a reduction of gastric cancer mortality in diabetic patients and in the general population in a dose-response manner, respectively.

Hepatocellular Carcinoma and Statins

HMG-CoA reductase inhibitors (known as statins) are commonly prescribed worldwide for the management of coronary heart disease and the underlying dyslipidemia. This class of drugs has been shown to infer a significant decrease in the risk of cardiovascular morbidity and mortality. Only recently though have the beneficial effects of statins in other diseases such as non-alcoholic steatohepatitis been highlighted. Importantly, also, multiple studies have revealed that statin use was associated with lower cancer-associated mortality across multiple types of cancers. This work aims to review those studies with a particular focus on liver cancer. We also provide a review of the proposed mechanisms of action describing how statins can induce chemo-preventive and antitumor effects.

Efficacy and Safety of the Combination of Pravastatin and Sorafenib for the Treatment of Advanced Hepatocellular Carcinoma (ESTAHEP Clinical Trial)

Pravastatin has demonstrated anti-tumor activity in preclinical and clinical studies. This multicentric randomized double-blind placebo-controlled phase II study (NCT01418729) investigated the efficacy and safety of sorafenib + pravastatin combination on the overall survival (OS) and time to progression (TTP) of patients with advanced hepatocellular carcinoma (aHCC). A total of 31 patients were randomized. Median OS did not differ between both groups (12.4 months for the sorafenib + pravastatin group vs. 11.6 months for the control group). Of note, however, the radiological TTP was higher in patients treated with sorafenib + pravastatin than in the control group (9.9 months vs. 3.2 months; p = 0.008). Considering all the study population, the presence of portal vein thrombosis (PVT) was associated with worse OS, being lower in patients with PVT compared to patients without PVT (6.3 months vs. 14.8 months; p = 0.026). Data also showed a decrease in OS in patients with vascular invasion (VI) compared to patients who did not present it (6.3 months vs. 14.8 months; p = 0.041). The group of patients without dermatological events (DE) showed lower OS (6.9 months vs. 14.5 months; p = 0.049). In conclusion, combination of sorafenib + pravastatin was safe and well-tolerated, prolonging the TTP of patients with aHCC but not improving the OS compared to sorafenib + placebo. The absence of PVT and VI and the development of DE are positive prognostic factors of sorafenib response.

Statin Use and the Risk of Hepatocellular Carcinoma: A Meta-Analysis of Observational Studies

Background and Aims: Statins are the first-line medication to treating hypercholesterolemia. Several studies have investigated the impact of statins on the risk of hepatocellular carcinoma (HCC). However, the extent to which statins may prevent HCC remains uncertain. Therefore, we performed a meta-analysis of relevant studies to quantify the magnitude of the association between statins use and the risk of HCC. Methods: A systematic literature search of PubMed, EMBASE, Google Scholar, Web of Science, and Scopus was performed for studies published between January 1, 1990, and September 1, 2019, with no restriction of language. Two reviewers independently evaluated the literature and included observational and experimental studies that reported the association between statin use and HCC risk. The random-effect model was used to calculate the overall risk ratio (RR) with a 95% confidence interval (CI), and the heterogeneity among the studies was assessed using the Q statistic and I² statistic. The Newcastle Ottawa Scale (NOS) was also used to evaluate the quality of the included studies. Results: A total of 24 studies with 59,073 HCC patients was identified. Statin use was associated with a reduced risk of HCC development (RR: 0.54, 95% CI: 0.47–0.61, I² = 84.39%) compared with nonusers. Moreover, the rate of HCC reduction was also significant among patients with diabetes (RR: 0.44, 95% CI: 0.28–0.70), liver cirrhosis (RR: 0.36, 95% CI: 0.30–0.42), and antiviral therapy (RR: 0.21, 95% CI: 0.08–0.59) compared with nonusers. Conclusion: This study serves as additional evidence supporting the beneficial inhibitory effect of statins on HCC incidence. The subgroup analyses of this study also highlight that statins are significantly associated with a reduced risk of HCC and may help to direct future prevention efforts. Additional large clinical studies are needed to determine whether statins are associated with a lower risk of HCC.

Retrospective cohort study of statin therapy effect on resected colorectal liver metastases

BACKGROUND

Above and beyond their role in cardiovascular risk reduction, statins appear to have a chemopreventive role in some gastro-intestinal cancers. In the quest for new chemopreventive agents, some existing established drugs such as statins have shown potential for re-purposing as chemoprevention. Probing existing drugs, whose pharmacodynamics are familiar, for novel beneficial effects offers a more cost-effective and less time-consuming strategy than establishing brand new drugs whose pharmacodynamic profile is unfamiliar. Observational studies show statins decrease the risk of developing colorectal cancer but there are no published studies exploring the potential impact of statins on carcinogenesis in colorectal liver metastases (CRLM).

AIM

To evaluate impact of statins on outcomes of CRLM resection, and secondarily to assess if statins influence CRLM histo-pathology.

METHODS

We conducted a retrospective cohort study of patients operated for CRLM over a 13-year period from 2005 to 2017. Patients were identified from a prospective database maintained in our Tertiary care hospital. All 586 patients included the study had undergone resection of CRLM following discussion at multidisclipinary team meeting, some patients requiring neoadjuvant chemotherapy to downstage CRLM prior to surgery. We analysed patient demographics, operative details, CRLM histopathology, Index of Deprivation, neutrophil-to-lymphocyte ratio, platelet-to-lymphocyte ratio and chemotherapy use in relation to clinical outcome. Statistics were performed using SPSS version 16.0; significance taken at 5%.

RESULTS

Liver resection for CRLM was undertaken in 586 patients at a median age of 68 (range 19 to 88) years. Statin therapy was used by 181 patients. Median follow-up time was 23 (range 12-96) mo and further colorectal cancer metastases developed in 267 patients. A total of 131 patients died. Multi-variate analysis identified 6 independent predictors of poorer disease-free survival: Synchronous presentation, multiple tumours, tumour size ≥ 5 cm, moderate–severe steatosis, peri-neural invasion, and R1-resection margin. Poorer overall survival was significantly associated with neo-adjuvant chemotherapy, major hepatectomy, peri-neural invasion and R1-resection margin. Neither histo-pathological nor radiological traits of CRLM were affected by statins, and, there was no demonstrable effect of statin therapy on patient outcomes.

CONCLUSION

Statin therapy does not affect patient survival following liver resection for CRLM. We postulate the reason for this key finding is that statins do not modulate tumour biology of CRLM.

Statin therapy does not influence the outcome of patients undergoing surgery for pancreatic cancer

BACKGROUND

Recently, statins have been associated with improved survival in certain cancers. The aim of this study was to evaluate the impact of statins on the outcome of patients undergoing surgery for pancreatic cancer. In addition, the effect of statins on the histopathological characteristics of the disease was assessed.

METHODS

A retrospective review of the prospectively maintained hepato-pancreatico-biliary database was performed and patients with pancreatic cancer who underwent surgery between January 2014 and December 2017 were included. Statistical analysis was performed to assess the impact of statins on histopathological characteristics and survival outcome.

RESULTS

A total of 151 patients were included, of whom 71 underwent pancreatic resections and 80 underwent trial dissection and bypass procedures. In the operated group, 20 patients were on statin therapy preoperatively. With respect to disease-free survival, tumour size (P = 0.023) and lymphatic invasion (P = 0.015) were significant variables on univariate analysis. Gender (P = 0.022), adjuvant chemotherapy (P < 0.001), lymphatic invasion (P = 0.021) and tumour size (P = 0.041) were significant variables on univariate analysis with respect to overall survival. Multivariate analysis identified adjuvant chemotherapy as the only independent predictor of overall survival (P < 0.001). No correlations between the use of statins and the histopathological characteristics were identified.

CONCLUSION

Adjuvant chemotherapy is an independent predictor of overall survival in patients undergoing surgery for pancreatic cancer. Statin therapy does not influence survival outcomes and histopathological characteristics following surgery for pancreatic cancer.

Statin uses and mortality in colorectal cancer patients: An updated systematic review and meta-analysis

BACKGROUND

Colorectal cancer (CRC) remains one of the most common types of cancer and a leading cause of death worldwide. Previous studies indicated that statins may have a potential protective effect on CRC.

METHODS

We conducted this meta-analysis to systematically assess the overall and cancer-specific survival benefit of statin uses on CRC patients. Related references were identified through PubMed, the Cochrane Library, Web of Science, EMBASE, and SCOPUS from inception to August 2017. Adjusted hazard ratios (HRs) were adopted to calculate summary hazard ratios (HRs) with 95% confidence intervals (95% CIs), using a random-effects model.

RESULTS

Total fourteen studies involving 130 994 patients were included in this meta-analysis. Six studies reported the association between pre-diagnosis statin uses and CRC mortality, while 11 studies investigated mortality in patients using statins after CRC diagnosis. For pre-diagnosis statin uses, the pooled HR of all-cause mortality (ACM) was 0.85 (95% CI, 0.79-0.92) and the pooled HR of cancer-specific mortality (CSM) was 0.82 (95% CI, 0.79-0.86). In terms of post-diagnosis statin uses, the pooled HR of ACM was 0.86 (95% CI, 0.76-0.98), and the pooled HR of CSM was 0.79 (95% CI, 0.70-0.89). For post-diagnosis statin uses, there is no difference in ACM when stratified by KRAS gene (KRAS) mutation status. Results of ACM and CSM did not markedly alter in other subgroup analyses.

CONCLUSION

Our meta-analysis demonstrates that both pre-diagnosis and post-diagnosis statin uses are associated with reduced ACM and CSM for CRC patients.

Biocatalyzed Synthesis of Statins: A Sustainable Strategy for the Preparation of Valuable Drugs

Statins, inhibitors of 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase, are the largest selling class of drugs prescribed for the pharmacological treatment of hypercholesterolemia and dyslipidaemia. Statins also possess other therapeutic effects, called pleiotropic, because the blockade of the conversion of HMG-CoA to (R)-mevalonate produces a concomitant inhibition of the biosynthesis of numerous isoprenoid metabolites (e.g., geranylgeranyl pyrophosphate (GGPP) or farnesyl pyrophosphate (FPP)). Thus, the prenylation of several cell signalling proteins (small GTPase family members: Ras, Rac, and Rho) is hampered, so that these molecular switches, controlling multiple pathways and cell functions (maintenance of cell shape, motility, factor secretion, differentiation, and proliferation) are regulated, leading to beneficial effects in cardiovascular health, regulation of the immune system, anti-inflammatory and immunosuppressive properties, prevention and treatment of sepsis, treatment of autoimmune diseases, osteoporosis, kidney and neurological disorders, or even in cancer therapy. Thus, there is a growing interest in developing more sustainable protocols for preparation of statins, and the introduction of biocatalyzed steps into the synthetic pathways is highly advantageous—synthetic routes are conducted under mild reaction conditions, at ambient temperature, and can use water as a reaction medium in many cases. Furthermore, their high selectivity avoids the need for functional group activation and protection/deprotection steps usually required in traditional organic synthesis. Therefore, biocatalysis provides shorter processes, produces less waste, and reduces manufacturing costs and environmental impact. In this review, we will comment on the pleiotropic effects of statins and will illustrate some biotransformations nowadays implemented for statin synthesis.

Simvastatin, but not pravastatin, inhibits the proliferation of esophageal adenocarcinoma and squamous cell carcinoma cells: a cell-molecular study

Background and objective

Long-term statin therapy has been shown to protect against several cancers, including esophageal cancer (EC). While the mechanisms underlying this effect are not clear. We investigated the effect of hydrophobic simvastatin and hydrophilic pravastatin on the proliferation of EC cells and sought to explore the underlying mechanisms.

Methods

Esophageal adenocarcinoma OE-19 cells and esophageal squamous cell carcinoma Eca-109 cells were treated with different concentrations of simvastatin or pravastatin for 24 h and 48 h. Cell proliferation was assessed by Cell Counting Kit-8 assay. Malondialdehyde (MDA) levels were measured by thiobarbituric acid (TBA) assay. mRNA and protein expression of COX-2 were determined by reverse transcriptase-polymerase chain reaction (RT-PCR) and Western blot, respectively; The expression of prostaglandin E₂ (PGE₂) was measured by ELISA.

Results

Simvastatin, but not pravastatin, significantly inhibited the proliferation of OE-19 and Eca-109 cells in a dose- and time-dependent manner, accompanying with the increasing of the MDA level. Moreover, simvastatin suppressed the expression of COX-2 and PGE₂ in both OE-19 and Eca-109 cells in a dose-dependent manner.

Conclusions

Lipophilic simvastatin, but not hydrophilic pravastatin, had significant inhibitory effects on the proliferation of Eca-109 and OE-19 cells. The reduction of COX-2 and PGE₂ by simvastatin suggested that the inhibitory effect of simvastatin on the proliferation of EC cells may be independent of its lipid-lowering effect. Simvastatin may be a promising agent for the prevention and treatment of EC.

Melatonin May Increase Anticancer Potential of Pleiotropic Drugs

Melatonin (N-acetyl-5-methoxytryptamine) is not only a pineal hormone, but also an ubiquitary molecule present in plants and part of our diet. Numerous preclinical and some clinical reports pointed to its multiple beneficial effects including oncostatic properties, and as such, it has become one of the most aspiring goals in cancer prevention/therapy. A link between cancer and inflammation and/or metabolic disorders has been well established and the therapy of these conditions with so-called pleiotropic drugs, which include non-steroidal anti-inflammatory drugs, statins and peroral antidiabetics, modulates a cancer risk too. Adjuvant therapy with melatonin may improve the oncostatic potential of these drugs. Results from preclinical studies are limited though support this hypothesis, which, however, remains to be verified by further research.

A Single Arm, Phase II Study of Simvastatin Plus XELOX and Bevacizumab as First-Line Chemotherapy in Metastatic Colorectal Cancer Patients

Purpose

Simvastatin has demonstrated anti-tumor activity in preclinical studies via tumor cell senescence, apoptosis, and anti-angiogenesis. This phase II trial evaluated the efficacy and toxicity profile of conventional XELOX and bevacizumab chemotherapy plus simvastatin in metastatic colorectal cancer patients (MCRC).

Materials and Methods

Patients with MCRC received first-line XELOX in 3-week treatment cycles of intravenous oxaliplatin 130 mg/m² plus bevacizumab 7.5 mg/kg (day 1), followed by oral capecitabine 1,000 mg/m² twice daily (day 1-14). Simvastatin 80 mg tablets were taken orally once daily every day during the period of chemotherapy. The primary endpoint was progression-free survival (PFS). Secondary endpoints were response rate, duration of response, overall survival (OS), time to progression, and toxicity.

Results

From January 2014 to April 2015, 60 patients were enrolled and 55 patients were evaluable for tumor response. The median follow-up duration was 30.1 months (range, 28.5 to 31.7 months). The median PFS was 10.4 months (95% confidence interval [CI], 9.6 to 11.1). The median OS of all patients was 19.0 months (95% CI, 11.9 to 26.0). The disease-control rate and overall response rate were 88.3% (95% CI, 74 to 96) and 58.3% (95% CI, 44 to 77), respectively, by intent-to-treat protocol analysis. There was one complete response and 34 partial responses. One patient experienced grade 3 creatine kinase elevation and liver enzyme elevation.

Conclusion

Based on the current study, the addition of 80 mg simvastatin to XELOX and bevacizumab showed comparable clinical efficacy in patients with MCRC as first-line chemotherapy and did not increase toxicity.

Unraveling the Prenylation-Cancer Paradox in Multiple Myeloma with Novel Geranylgeranyl Pyrophosphate Synthase (GGPPS) Inhibitors

Post-translational prenylation of the small GTP-binding proteins (GTPases) is vital to a plethora of biological processes, including cellular proliferation. We have identified a new class of thienopyrimidine-based bisphosphonate (ThP-BP) inhibitors of the human geranylgeranyl pyrophosphate synthase (hGGPPS) that block protein prenylation in multiple myeloma (MM) cells leading to cellular apoptosis. These inhibitors are also effective in blocking the proliferation of other types of cancer cells. We confirmed intracellular target engagement, demonstrated the mechanism of action leading to apoptosis, and determined a direct correlation between apoptosis and intracellular inhibition of hGGPPS. Administration of a ThP-BP inhibitor to a MM mouse model confirmed in vivo downregulation of Rap1A geranylgeranylation and reduction of monoclonal immunoglobulins (M-protein, a biomarker of disease burden) in the serum. These results provide the first proof-of-principle that hGGPPS is a valuable therapeutic target in oncology and more specifically for the treatment of multiple myeloma.

A metabolite of nobiletin, 4'-demethylnobiletin and atorvastatin synergistically inhibits human colon cancer cell growth by inducing G0/G1 cell cycle arrest and apoptosis

Combining different chemopreventive agents is a promising strategy to reduce cancer incidence and mortality due to potential synergistic interactions between these agents. Previously, we demonstrated that oral administration of nobiletin (NBT, a citrus flavonoid) at 0.05% (w/w, in diet) together with atorvastatin (ATST, a lipid-lowering drug) at 0.02% (w/w, in diet) produced much stronger inhibition against colon carcinogenesis in rats in comparison with that produced by NBT (at 0.1% w/w in diet) or ATST (at 0.04% w/w in diet) alone at higher doses. To further elucidate the mechanism of this promising synergy between NBT and ATST, herein, we measured the levels of NBT, its major metabolites and ATST in the colonic tissue of rats fed NBT (0.05% w/w, in diet) + ATST (0.02% w/w, in diet), and determined the mode of interaction between the major NBT metabolite and ATST in inhibiting colon cancer cell growth. HPLC-MS analysis showed that 4'-demethylnobiletin (4DN) is the most abundant metabolite of NBT with a level about 5-fold as high as that of NBT in the colonic tissue, which indicated the potential significance of 4DN in mediating the biological effects of NBT in the colon. We found that co-treatments of 4DN/ATST at 2 : 1 concentration ratio produced much stronger growth inhibitory effects on human colon cancer HT-29 cells than 4DN or ATST alone, and isobologram analysis confirmed that this enhanced inhibitory effect by the 4DN/ATST combination was highly synergistic. The co-treatment of 4DN/ATST led to G0/G1 cell cycle arrest and induced extensive apoptosis in HT-29 cells. Furthermore, the 4DN/ATST co-treatment profoundly modulated key signaling proteins related to the regulation of the cell cycle and apoptosis. Our results demonstrated a strong synergy produced by the 4DN/ATST co-treatment in inhibiting colon cancer cell growth, which provided a novel mechanism by which NBT/ATST in combination synergistically inhibit colon carcinogenesis.

Chemical genetics in tumor lipogenesis

Since cancer cells depend on de novo lipogenesis for energy supply, highly active membrane biosynthesis and signaling, enhanced fatty acid synthesis is a crucial characteristic of cancer cells. Hence, targeting lipogenic enzymes and signaling cascades is a very promising approach in developing innovative therapeutic agents for the fight against cancer. This review summarizes main aspects of altered fatty acid synthesis in cancer cells and emphasizes the power of chemical genetic approaches in identifying and analyzing novel anti-cancer drug candidates interfering with lipid metabolism.

Statin use is not associated with improved 30-day survival in patients undergoing surgery for colorectal cancer

PURPOSE

Besides the lipid-lowering properties, statins are thought to have anti-inflammatory effects and it has been shown that statins directly attenuate the inflammatory stress response after surgical trauma. The aim of the study was to examine the association between preoperative statin use and 30-day mortality as well as postoperative complications after curative-intended surgery for colorectal cancer.

METHODS

The study was a Danish nationwide register-based observational study. A total of 29,352 patients undergoing surgery for colorectal cancer between January 1, 2003, and December 31, 2012, were included in the study. At the time of surgery, 5961 were registered as statin users. The outcomes were 30-day mortality and risk of postoperative complications.

RESULTS

The adjusted hazard ratio of 30-day mortality was 0.91 (95 CI 0.80-1.04, P = 0.16) among statin users compared with the non-statin group. There was no difference between the two groups regarding the risk of infectious complications (sepsis, anastomotic leakage, pneumonia) (odds ratio 0.95, 95% CI 0.86-1.05, P = 0.31). For other postoperative complications (cardiovascular events, stroke, renal failure, respiratory insufficiency, and thromboembolic events), there was no significant difference between the two groups (odds ratio 0.89, 95% CI 0.78-1.01, P = 0.06).

CONCLUSION

The study did not show an improved 30-day survival after surgery for colorectal cancer in patients treated with statins in the year preceding surgery. No overall association with the risk of postoperative complications was shown.

Hepatotoxicity associated with statins

Treatment with statins is known all over the world. They are generally considered safe at therapeutic doses. Nevertheless, clinical trials are not enough to assess their scarce adverse effects such as idiosyncratic drug induced liver injury (DILI). Due to some conditions, such as concomitant usage (drug-drug interaction using an identical metabolising enzyme) and genetic polymorphisms, there is an increasing concern about their safety. Hepatotoxicity and rhabdomyolysis have begun to appear in published studies. Most of investigations have focused on both these adverse effects and mechanisms of drug induced toxicity. The present review has attempted to compile almost all of the existing studies on the hepatotoxicity of statins but not rhabdomyolysis. The aim of our study is to provide an overview of the studies on the statin-associated hepatotoxicity and to discuss the published studies. The researchers are of the opinion that the research on this topic is incomplete but extremely necessary.

Differences of statin activity in 2D and 3D pancreatic cancer cell cultures

Purpose

To evaluate the anticancer activity of lovastatin (LOVA), mevastatin (MEVA), pitavastatin (PITA), and simvastatin (SIMVA) in 2D and 3D models of three human pancreatic cancer cell lines (BxPC-3, MIA PaCa-2, and PANC-1).

Methods

The effect of statins on cell viability was estimated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide test. The activity of statins in 3D pancreatic cancer cell cultures was examined by measuring the size change of spheroids. The type of cell death was identified by cell staining with Hoechst 33342 and propidium iodide. The activity of statins on the clonogenicity of cancer cells was tested by evaluating the effect on the colony-forming ability of cells.

Results

The rank order of the activity of tested statins on cell viability was as follows: PITA > SIMVA > LOVA > MEVA. Among the tested statins, PITA had the greatest effect on cell viability (half maximal effective concentration values after 72 h on BxPC-3, MIA PaCa-2, and PANC-1 cells were 1.4±0.4 μM, 1.0±0.2 μM, and 1.0±0.5 μM, respectively). PITA also showed the strongest effect on tumor spheroid growth. Statins suppressed the colony formation of cancer cells. PITA demonstrated the greatest reduction in colony size and number. Apoptosis and necrosis assay results showed that at lower concentrations statins mostly induced cell death through apoptosis, whereas higher concentrations of compounds activated also necrotic processes.

Conclusion

Statins, especially PITA, demonstrate an anticancer activity against pancreatic cancer cell lines BxPC-3, MIA PaCa-2, and PANC-1 in both 2D and 3D models.

Additional Benefits of Routine Drugs on Gastrointestinal Cancer: Statins, Metformin, and Proton Pump Inhibitors

BACKGROUND

Commonly used medications including statins, metformin, and proton pump inhibitors (PPIs) effectively reduce the risk of esophageal, gastric, and colorectal cancer (CRC).

SUMMARY

A number of observational studies and meta-analyses have shown that long-term statin use significantly reduces the incidence of gastrointestinal (GI) cancer. Moreover, statin use after GI cancer diagnosis has been significantly associated with better prognosis in large-scale cohort studies. Metformin was rigorously evaluated in a population-based study and meta-analysis, and was found to have an unexpected benefit in the prevention and prolonged survival of CRC patients with type 2 diabetes mellitus. In contrast, few studies have demonstrated the chemopreventive effect of metformin for esophageal and gastric cancer. Recent observational studies have demonstrated that PPIs effectively reduce the progression of nondysplastic Barrett's esophagus into esophageal adenocarcinoma in a dose-dependent manner. However, the association between chronic PPI use and CRC or gastric cancer risk is still controversial. It was expected that these 3 routinely used medicines would show a synergistic effect with conventional systemic chemotherapy in advanced GI cancers. However, recent phase III studies failed to show significantly better outcomes. Key Messages: Further studies are needed to identify "additional" anticancer effects of these commonly used medicines.

Statin and rottlerin small-molecule inhibitors restrict colon cancer progression and metastasis via MACC1

MACC1 (Metastasis Associated in Colon Cancer 1) is a key driver and prognostic biomarker for cancer progression and metastasis in a large variety of solid tumor types, particularly colorectal cancer (CRC). However, no MACC1 inhibitors have been identified yet. Therefore, we aimed to target MACC1 expression using a luciferase reporter-based high-throughput screening with the ChemBioNet library of more than 30,000 compounds. The small molecules lovastatin and rottlerin emerged as the most potent MACC1 transcriptional inhibitors. They remarkably inhibited MACC1 promoter activity and expression, resulting in reduced cell motility. Lovastatin impaired the binding of the transcription factors c-Jun and Sp1 to the MACC1 promoter, thereby inhibiting MACC1 transcription. Most importantly, in CRC-xenografted mice, lovastatin and rottlerin restricted MACC1 expression and liver metastasis. This is-to the best of our knowledge-the first identification of inhibitors restricting cancer progression and metastasis via the novel target MACC1. This drug repositioning might be of therapeutic value for CRC patients.

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

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

Intracellular cholesterol transport proteins: roles in health and disease

Effective cholesterol homoeostasis is essential in maintaining cellular function, and this is achieved by a network of lipid-responsive nuclear transcription factors, and enzymes, receptors and transporters subject to post-transcriptional and post-translational regulation, whereas loss of these elegant, tightly regulated homoeostatic responses is integral to disease pathologies. Recent data suggest that sterol-binding sensors, exchangers and transporters contribute to regulation of cellular cholesterol homoeostasis and that genetic overexpression or deletion, or mutations, in a number of these proteins are linked with diseases, including atherosclerosis, dyslipidaemia, diabetes, congenital lipoid adrenal hyperplasia, cancer, autosomal dominant hearing loss and male infertility. This review focuses on current evidence exploring the function of members of the ‘START’ (steroidogenic acute regulatory protein-related lipid transfer) and ‘ORP’ (oxysterol-binding protein-related proteins) families of sterol-binding proteins in sterol homoeostasis in eukaryotic cells, and the evidence that they represent valid therapeutic targets to alleviate human disease.

Pleiotropic effects of statins on acute kidney injury: involvement of Krüppel-like factor 4

Statins, the inhibitors of 3-hydroxy-3-methylglutaryl-coenzyme A reductase, are potent cholesterol-lowering drugs used for primary and secondary prevention of coronary artery disease. They also possess multiple beneficial effects independent of their cholesterol-lowering properties, which are called as their "pleiotropic" effects. The results of recent studies have revealed that statins exert their pleiotropic effects in the kidneys, in that they are protective against acute kidney injury (AKI). Moreover, Krüppel-like factor 4, a zinc-finger transcription factor, in endothelial cells has been identified as a novel mediator of statins. This article summarizes the pleiotropic effects of statins on AKI, and reviews the recent progress in our understanding of the regulatory mechanisms involved in statin-mediated protection against AKI.

Cancer metabolism: a therapeutic perspective

Awareness that the metabolic phenotype of cells within tumours is heterogeneous - and distinct from that of their normal counterparts - is growing. In general, tumour cells metabolize glucose, lactate, pyruvate, hydroxybutyrate, acetate, glutamine, and fatty acids at much higher rates than their nontumour equivalents; however, the metabolic ecology of tumours is complex because they contain multiple metabolic compartments, which are linked by the transfer of these catabolites. This metabolic variability and flexibility enables tumour cells to generate ATP as an energy source, while maintaining the reduction-oxidation (redox) balance and committing resources to biosynthesis - processes that are essential for cell survival, growth, and proliferation. Importantly, experimental evidence indicates that metabolic coupling between cell populations with different, complementary metabolic profiles can induce cancer progression. Thus, targeting the metabolic differences between tumour and normal cells holds promise as a novel anticancer strategy. In this Review, we discuss how cancer cells reprogramme their metabolism and that of other cells within the tumour microenvironment in order to survive and propagate, thus driving disease progression; in particular, we highlight potential metabolic vulnerabilities that might be targeted therapeutically.

The effect of statins on cancer cells--review

Statins [3-hydroxy-3-methylglutaryl-coenzyme A reductase (HMG-CoA reductase, abbreviated HMGCR) inhibitors], are well-known cholesterol-depleting agents. Since the early 1990 s, it has been known that statins could be successfully used in cancer therapy, but the exact mechanism(s) of statin activity remains unclear and is now an extensive focus of investigation. So far, it was proven that there are several mechanisms that are activated by statins in cancer cells; some of them are leading to cell death. Statins exert different effects depending on cell line, statin concentration, duration of exposure of cells to statins, and the type of statin being used. It was shown that statins may inhibit the cell cycle by influence on both expression and activity of proteins involved in cell-cycle progression such as cyclins, cyclin-dependent kinases (CDK), and/or inhibitors of CDK. Also, statins may induce apoptosis by both intrinsic and extrinsic pathways. Statin treatment may lead to changes in molecular pathways dependent on the EGF receptor, mainly via inhibition of isoprenoid synthesis. By inhibition of the synthesis of cholesterol, statins may destabilize the cell membrane. Moreover, statins may change the arrangement of transporter OATP1, the localization of HMGCR, and could induce conformational changes in GLUT proteins. In this review, we have tried to gather and compare most of the recent outcomes of the research in this field. We have also attempted to explain why hydrophilic statins are less effective than hydrophobic statins. Finally, we have gathered results from in vivo experiments, presenting the use of statins in combined therapies and discussed a number of molecular targets that could serve as biomarkers predisposing to statin therapy.