Prospective analysis of association between use of statins and melanoma risk in the Women's Health Initiative

Association of lipid-lowering drug targets with risk of cutaneous melanoma: a mendelian randomization study

BACKGROUND

Melanoma proliferation is partly attributed to dysregulated lipid metabolism. The effectiveness of lipid-lowering drugs in combating cutaneous melanoma (CM) is a subject of ongoing debate in both in vitro and clinical studies.

METHOD

This study aims to evaluate the causal relationship between various lipid-lowering drug targets, namely 3-hydroxy-3-methylglutaryl-coenzyme A reductase (HMGCR, targeted by statins), Proprotein convertase subtilisin/kexin type 9 (PCSK9, targeted by alirocumab and evolocumab), and Niemann-Pick C1-like 1 (NPC1L1, targeted by ezetimibe), and the outcomes of cutaneous melanoma. To mimic the effects of lipid-lowering drugs, we utilized two genetic tools: analysis of polymorphisms affecting the expression levels of drug target genes, and genetic variations linked to low-density lipoprotein cholesterol levels and drug target genes. These variations were sourced from genome-wide association studies (GWAS). We applied Summary-data-based Mendelian Randomization (SMR) and Inverse Variance Weighted Mendelian Randomization (IVW-MR) to gauge the effectiveness of these drugs.

RESULTS

Our findings, with SMR results showing an odds ratio (OR) of 1.44 (95% CI: 1.08-1.92; P = 0.011) and IVW-MR results indicating an OR of 1.56 (95% CI: 1.10-2.23; P = 0.013), demonstrate a positive correlation between PCSK9 expression and increased risk of CM. However, no such correlations were observed in other analyses.

CONCLUSION

The study concludes that PCSK9 plays a significant role in the development of CM, and its inhibition is linked to a reduced risk of the disease.

Hispanic adults with type 2 diabetes mellitus using lipid-lowering agents have better periodontal health than non-users

Background

Recent studies suggest that lipid-lowering agents (LLA) may reduce chronic periodontitis, but it is unknown whether this benefit extends to people with type 2 diabetes (T2D).

Objective

We assessed the association between LLA use and periodontitis in Hispanic adults with T2D.

Design

This was a cross-sectional observational study.

Methods

We assessed the association of LLA use and periodontal parameters in 253 Puerto Ricans 40-65 years with T2D who participated in the Lipid-Lowering agents use in Periodontitis and Diabetes Study study. Participants were classified as (a) none- or <1 year, (b) 1-4 years, or (c) >4 years. The primary outcome consists of a tertile percent of sites with probing pocket depth (PPD) ⩾ 4 mm and the secondary outcome includes tertiles of percent sites with clinical attachment loss (CAL) ⩾ 4 mm. Multinomial logistic regression models adjusted for age, gender, smoking status, education, waist circumference, glycosylated hemoglobin A1C (HbA1c), bleeding on probing, examiner, and anti-inflammatory agents were used to estimate the association.

Results

LLA (92.5%, statins) was used by 52% of participants. LLA use 1-4 years was associated with lower odds of PPD ⩾ 4 mm (OR: 0.22, p = 0.005; high versus low tertile) or lower odds of CAL ⩾ 4 mm (OR: 0.33, p = 0.02, middle versus low tertile), compared to those with LLA minimal or no use. This association was lost for participants who used LLA for >4 years. LLA users for >4 years with periodontal disease had elevated HbA1c (OR: 1.36, p = 0.05).

Conclusion

The use of LLA for 1-4 years was associated with lower values of periodontal parameters versus minimal LLA use. This association was not present among people using LLA > 4 years users, but these participants had poorer glycemic control compared to other participants. In this cross-sectional study, the finding that LLA use 1- 4 years is associated with lower values of periodontal parameters of severity in T2D individuals may help clarify some of the controversies regarding the benefit of these medications in this population.

Low-Dose Atorvastatin has Promoting Effect on Melanoma Tumor Growth and Angiogenesis in Mouse Model

Background

Preclinical evidence indicates that statins possess diverse antineoplastic effects in different types of tumors. However, clinical studies have yielded conflicting results regarding the potential of statins to either increase or decrease the risk of cancer. Our objective was to examine the relationship between the dose of a treatment and its impact on melanoma tumor growth and angiogenesis in an in vivo setting.

Materials and Methods

Melanoma cells were injected into C57BL6 mice in four groups. They received 0, 1, 5, and 10 mg/kg of atorvastatin daily. Three others received the mentioned doses one week before the inoculation of melanoma animals. At the end of the third week, the animals were euthanized in a humane manner, and both blood samples and tumor specimens were collected for subsequent analysis.

Results

The tumor size was 1.16 ± 0.25 cm3 in a group treated with therapeutic dose of atorvastatin and was significantly larger than that in the control group (0.42 ± 0.08 cm3). However, there were no significant differences between the two other doses and the control group (0.72 ± 0.22, 0.46 ± 0.08 cm3 in atorvastatin-treated groups with 5 and 10 mg/kg). The vascular density of the tumors was significantly increased in the lowest dose of the atorvastatin treatment group, similar to the results of tumor size (P < 0.05).

Conclusion

Atorvastatin, at low therapeutic concentrations, has been observed to stimulate tumor growth and exhibit pro-angiogenic effects. Therefore, it is advised to exercise caution and recommend clinically relevant doses of statins to patients with cancer.

Association between statins exposure and risk of skin cancer: an updated meta-analysis

This study aimed to investigate the relationship between statin (lipophilic statin and hydrophilic statin) exposure and the risk of skin cancer. The incidence of skin cancer under statin exposure was used as the primary outcome, and the relevant studies were screened from Web of Science, PubMed, Cochrane Library, and EBSCO electronic database until September 2022. Ten observational studies and two randomized controlled trials (RCTs) were included. The statistical results indicated that in lipophilic statins, the exposed group had a higher risk of skin cancer than the non-exposed group (OR: 1.09, P = 0.003). However, compared with the non-exposed group, there was no significant difference between hydrophilic statins exposure and the incidence of skin cancer (OR: 1.02, P = 0.341). Further subgroup analysis of the subtypes of statins revealed that compared with the non-exposed group, exposure to lovastatin (OR: 1.18, P = 0.048) or simvastatin (OR: 1.11, P < 0.001) was a risk factor for skin cancer. Besides, subgroup analysis based on the subtypes of skin cancer demonstrated that the risks of melanoma (OR: 1.13, P = 0.009), basal cell carcinoma (BCC) (OR: 1.05, P = 0.036), and squamous cell carcinoma (SCC) (OR: 1.13, P = 0.026) under lipophilic statin exposure were significantly higher than those in the non-exposed group. On the contrary, compared with the non-exposed group, the risk of BCC was significantly reduced under the exposure of hydrophilic statins (OR: 0.93, P = 0.031). This study showed that the relationship between statin exposure and skin cancer risk was affected by the subtypes of statins and skin cancer subtypes.

Ulcerated Cutaneous Melanoma: A Review of the Clinical, Histologic, and Molecular Features Associated with a Clinically Aggressive Histologic Phenotype

The presence of ulceration in melanoma is associated with poor clinical outcomes and is the third most powerful predictor of survival in the AJCC Melanoma Staging System after tumor thickness and mitotic activity. The aggressive biological behavior associated with ulceration has been hypothesized to be the result of an intrinsic biological attribute that favors dissemination and presents locally with the loss of epidermal integrity. Among the features of ulcerated melanoma, many show promise as potential prognostic tools, markers of differential immunogenicity and indicators of oncogenic drivers of invasion and metastasis. The incidence of ulcerated melanoma is greater in males, increases with age and with systemic inflammatory risk factors (diabetes, smoking, low vitamin D, elevated body mass index). Patients with ulcerated primary tumors seem to exclusively benefit from adjuvant interferon (IFN) therapy, which is likely the consequence of an altered tumor microenvironment. When ulceration is present, there is a higher density of macrophages and dendritic cells and enhanced expression of pro-inflammatory cytokines, such as IL-6. There is also an increased expression of proteins involved in tumor antigen presentation in ulcerated melanomas. Histologically, vascular density, vasculogenic mimicry and angiotropism are all significantly correlated with ulceration in melanoma. The presence of ulceration is associated with reduced protein expression of E-cadherin and PTEN and elevated levels of N-cadherin and the matrix metalloproteinases. Differential microRNA expression also holds promise as a potential prognostic biomarker of malignancy and disease spread within the setting of ulceration. However, the molecular and cellular differences associated with the ulcerated state are complex and further study will aid in determining how these differences can be harnessed to improve care for patients with melanoma.

Computational Drug Repositioning Identifies Statins as Modifiers of Prognostic Genetic Expression Signatures and Metastatic Behavior in Melanoma

Despite advances in melanoma treatment, more than 70% of patients with distant metastasis die within 5 years. Proactive treatment of early melanoma to prevent metastasis could save lives and reduce overall healthcare costs. Currently, there are no treatments specifically designed to prevent early melanoma from progressing to metastasis. We used the Connectivity Map to conduct an in silico drug screen and identified 3-hydroxy-3-methylglutaryl-coenzyme A reductase inhibitors (statins) as a drug class that might prevent melanoma metastasis. To confirm the in vitro effect of statins, RNA sequencing was completed on A375 cells after treatment with fluvastatin to describe changes in the melanoma transcriptome. Statins induced differential expression in genes associated with metastasis and are used in commercially available prognostic tests for melanoma metastasis. Finally, we completed a chart review of 475 patients with melanoma. Patients taking statins were less likely to have metastasis at the time of melanoma diagnosis in both univariate and multivariate analyses (24.7% taking statins vs. 37.6% not taking statins, absolute risk reduction = 12.9%, P = 0.038). These findings suggest that statins might be useful as a treatment to prevent melanoma metastasis. Prospective trials are required to verify our findings and to determine the mechanism of metastasis prevention.

Application of EPR spectroscopy to determine the influence of simvastatin concentration on free radicals in A-375 human melanoma malignum cells

Malignant melanoma is the most aggressive and lethal form of skin cancer. Therefore the search for new methods of the treatment for melanoma is needed. In this work simvastatin was tested as the substance of potential anticancer activity. The aim of this study was to determine the effect of simvastatin in different concentration on free radicals in A-375 human melanoma malignum cells. Free radicals and growth of A-375 melanoma cells cultured without and with simvastatin were examined. Free radicals were tested by the use of electron paramagnetic resonance (EPR) spectroscopy. o-Semiquinone free radicals existed in A-375 cells. Free radicals of the control A-375 cells and the cells cultured with simvastatin were homogeneously broadened. The growth of A-375 cells did not change for concentrations of simvastatin 0.1 μM and 0.3 μM, and it slightly decreased for concentration of this substance equal 1 μM, so these concentrations of simvastatin were not preferred for therapy. For the concentrations of simvastatin higher than 1 μM the growth of A-375 cells was considerably weakened. Simvastatin in the concentrations of 0.1 μM and 1 μM decreased free radical concentrations in A-375 cells. The concentrations of simvastatin of 3 μM and 5 μM accompanied by the strong cell damage and strong formation of free radicals in them were recommended for anticancer therapy of A-375 melanoma cells.

Effect of simvastatin in different concentrations on free radicals in A-2058 human melanoma malignum cells-EPR studies

The influence of concentration of simvastatin (SIM) on free radicals in A-2058 human melanoma malignum cells was studied. The proliferation assay for melanoma A-2058 cells with SIM in concentration range from 0.1 to 20 µM was performed. SIM in the concentrations of 0.1, 0.3, and 1 μM only slightly changed the growth of A-2058 cells, but the growth of the cells considerably decreased for higher concentrations of SIM. Free radicals in the cells were examined by an X-band (9.3 GHz) electron paramagnetic resonance (EPR) spectroscopy. o-Semiquinone free radicals with g-factors in the range of 2.0060 to 2.0065 were found in A-2058 cells. The asymmetric broad EPR spectra with linewidths (ΔB_pp ) from 0.87 to 1.25 mT were measured. The fast spin-lattice relaxation processes characterized all the tested cells. The free radical concentrations in the all A-2058 cells cultured with SIM were lower than in the control cells. The quenching of free radicals in A-2058 cells depended on concentration of SIM. This effect was the weakest for concentration of SIM of 3 μM. The strongest decrease of free radical concentration caused SIM in concentration of 1 μM.

Chemoprevention agents for melanoma: A path forward into phase 3 clinical trials

Recent progress in the treatment of advanced melanoma has led to unprecedented improvements in overall survival and, as these new melanoma treatments have been developed and deployed in the clinic, much has been learned about the natural history of the disease. Now is the time to apply that knowledge toward the design and clinical evaluation of new chemoprevention agents. Melanoma chemoprevention has the potential to reduce dramatically both the morbidity and the high costs associated with treating patients who have metastatic disease. In this work, scientific and clinical melanoma experts from the national Melanoma Prevention Working Group, composed of National Cancer Trials Network investigators, discuss research aimed at discovering and developing (or repurposing) drugs and natural products for the prevention of melanoma and propose an updated pipeline for translating the most promising agents into the clinic. The mechanism of action, preclinical data, epidemiological evidence, and results from available clinical trials are discussed for each class of compounds. Selected keratinocyte carcinoma chemoprevention studies also are considered, and a rationale for their inclusion is presented. These data are summarized in a table that lists the type and level of evidence available for each class of agents. Also included in the discussion is an assessment of additional research necessary and the likelihood that a given compound may be a suitable candidate for a phase 3 clinical trial within the next 5 years.

An analysis of the effect of statins on the risk of Non-Hodgkin's Lymphoma in the Women's Health Initiative cohort

Statins have been shown to induce a phosphoprotein signature that modifies MYC (myelocytomatosis viral oncogene) activation and to have anti‐inflammatory activity that may impact the risk of Non‐Hodgkin's lymphoma (NHL). We analyzed the relationship between statins and risk of NHL using data from the Women's Health Initiative (WHI). The study population included 161,563 postmenopausal women ages 50–79 years from which 712 cases of NHL were diagnosed after 10.8 years of follow‐up. Information on statin use and other risk factors was collected by self‐ and interviewer‐administered questionnaires. Multivariable‐adjusted HR and 95% CI evaluating the relationship between statin use at baseline, as well as in a time‐dependent manner and risk of NHL, were computed from Cox proportional hazards analyses. A separate analysis was performed for individual NHL subtypes: diffuse large B‐Cell lymphoma (DLBCL) (n = 228), follicular lymphoma (n = 169), and small lymphocytic lymphoma (n = 74). All statistical tests were two‐sided. There was no significant association between use of statins at baseline and risk of NHL (HR 0.85, 95% C.I. 0.67–1.08). However, in the multivariable‐adjusted time‐dependent models, statin use was associated with a borderline lower risk of NHL (HR 0.81, 95% C.I. 0.66–1.00). Considering subtypes of NHL, statin use was associated with a lower risk of DLBCL (HR 0.62, 95% C.I. 0.42–0.91). This effect was driven by lipophilic statins (HR 0.62, 95% C.I. 0.40–0.96). In the WHI, statins were associated with a lower overall risk of DLBCL, particularly attributable to lipophilic statins. These results may have impact on primary or secondary prevention of NHL, particularly DLBCL.

Statin use and risk of skin cancer

BACKGROUND

Statins are among the most commonly used medications in the United States, and statin use is associated with increased risk of basal cell carcinoma (BCC) and squamous cell carcinoma (SCC). However, previous studies are limited by lack of adjustment for important confounders.

OBJECTIVE

Examine the relation between statins and skin cancer risk in the Nurses' Health Study and Health Professionals Follow-up Study.

METHODS

Cox proportional hazards regression was used to evaluate associations.

RESULTS

During follow-up (2000-2010), we documented 10,201 BCC, 1393 SCC, and 333 melanoma cases. History of high cholesterol level was not associated with risk of BCC (pooled multivariable-adjusted hazard ratio [HR], 1.04; 95% confidence interval [CI], 1.00-1.09), SCC (HR, 0.95; 95% CI, 0.85-1.06), or melanoma (HR, 0.87; 95% CI, 0.64-1.19). Statin use was not associated with risk of BCC (HR, 1.04; 95% CI, 0.99-1.09]), SCC (HR, 1.08; 95% CI, 0.94-1.24), or melanoma (HR, 1.04; 95% CI, 0.78-1.38). There was a trend toward higher BCC risk with longer duration of statin use in men (P trend = .003) but not in women (P trend = .86).

LIMITATIONS

Lack of treatment data.

CONCLUSION

History of high cholesterol level was not associated with skin cancer risk. Longer duration of statin use was associated with a trend toward higher BCC risk in men.

An analysis of the association between statin use and risk of endometrial and ovarian cancers in the Women's Health Initiative

BACKGROUND

Statins have anti proliferative activity in vitro against endometrial and ovarian cancer and can affect levels of reproductive hormones. We analyzed data from the Women's Health Initiative (WHI) to assess whether statins are associated with risk of endometrial and ovarian cancer.

METHODS

The WHI study included 161,808 postmenopausal women in which incident cases of endometrial (n = 1377) and ovarian cancer (n = 763) were identified over an average of 10.8 (SD + 3.3) years. Information on statin use and risk factors was collected at baseline and follow-up. Cox proportional hazards regression was used to calculate hazard ratios (HRs) with 95% confidence intervals (CIs) for the association of statin use and risk of endometrial and ovarian cancer. All statistical tests were two-sided.

RESULTS

Statins were used at baseline by 7.5% women and by up to 25% at year nine. The multivariable adjusted HR for risk of endometrial cancer for baseline statin use was 0.74, 95% C.I. 0.59-0.94 and for ovarian cancer was 1.15, 95% C.I. 0.89-1.50. In time-dependent models, statins were not associated with endometrial cancer (HR 0.91, 95% C.I. 0.76-1.08) however there was an increased risk of ovarian cancer (HR 1.30, 95% CI 1.04-1.62), largely attributed to the effect of the hydrophilic statin, pravastatin (1.89, 95% CI 1.24-2.88).

CONCLUSIONS

There was a reduction in risk of endometrial cancer among statin users at baseline but not in time-dependent models. Pravastatin use was associated with an increased risk of ovarian cancer. Analyses of larger numbers of cases are needed to evaluate these findings.

Associations of Statins and Diabetes with Diagnosis of Ulcerated Cutaneous Melanoma

Ulcerated primary melanomas are associated with an inflammatory tumor microenvironment. We hypothesized that systemic proinflammatory states and anti-inflammatory medications are also associated with a diagnosis of ulcerated melanoma. In a cross-sectional study of 787 patients with newly diagnosed clinical stage IB or II melanoma, we estimated odds ratios for the association of proinflammatory factors (high body mass index, diabetes, cardiovascular disease, hypertension, and smoking) or the use of anti-inflammatory medications (statins, aspirin, corticosteroids, and nonsteroidal anti-inflammatory drugs), with ulcerated primary melanoma using regression models and subgroup analyses to control for melanoma thickness and mitotic rate. On the basis of information from 194 patients with ulcerated and 593 patients with nonulcerated primary melanomas, regular statin users had lower likelihood of a diagnosis of ulcerated primary melanoma (odds ratio 0.67, 95% confidence interval 0.45-0.99), and this association remained after adjusting for age, sex, thickness, and mitosis. When analysis was limited to melanomas that were ≤2 mm thick and had ≤2 mitoses/mm2 (40 ulcerated; 289 without ulceration), patients with diabetes had significantly raised odds of diagnosis of ulcerated melanoma (odds ratio 2.90, 95% confidence interval 1.07-7.90), adjusted for age, sex, body mass index, and statin use. These findings support our hypotheses that statin use is inversely associated, and diabetes is positively associated, with ulcerated melanoma.

Protective Effects of Statins in Cancer: Should They Be Prescribed for High-Risk Patients?

PURPOSE OF REVIEW

Statins are one of the most widely prescribed drug classes in the USA. This review aims to summarize recent research on the relationship between statin use and cancer outcomes, in the context of clinical guidelines for statin use in patients with cancer or who are at high risk for cancer.

RECENT FINDINGS

A growing body of research has investigated the relationship between statins and cancer with mixed results. Cancer incidence has been more extensively studied than cancer survival, though results are inconsistent as some large meta-analyses have not found an association, while other studies have reported improved cancer outcomes with the use of statins. Additionally, two large studies reported increased all-cancer survival with statin use. Studies on specific cancer types in relation to cancer use have also been mixed, though the most promising results appear to be found in gastrointestinal cancers. Few studies have reported an increased risk of cancer incidence or decreased survival with statin use, though this type of association has been more commonly reported for cutaneous cancers. The overall literature on statins in relation to cancer incidence and survival is mixed, and additional research is warranted before any changes in clinical guidelines can be recommended. Future research areas include randomized controlled trials, studies on specific cancer types in relation to statin use, studies on populations without clinical indication for statins, elucidation of underlying biological mechanisms, and investigation of different statin types. However, studies seem to suggest that statins may be protective and are not likely to be harmful in the setting of cancer, suggesting that cancer patients who already take statins should not have this medication discontinued.

Primary and Secondary Chemoprevention of Malignant Melanoma

The incidence of malignant melanoma (MM) continues to rise in the United States. While sun protection and full body skin examinations remain the mainstay of preventative care, chemoprevention of the deadly disease has become an increasingly popular field of study. In this focused review, we discuss current findings and analyze the risks and benefits of various agents investigated for the primary and secondary chemoprevention of MM. Such agents include topical retinoids, vitamins, and supplements, Polypodium leucotomas extracts, non-steroidal anti-inflammatory agents (NSAIDs), statins, sunscreens, and field therapy with topical imiquimod for primary and secondary chemoprevention. We further identify a need for expanded high quality human research on the topic.

Statin use and all-cancer survival: prospective results from the Women's Health Initiative

BACKGROUND

This study aims to investigate the association between statin use and all-cancer survival in a prospective cohort of postmenopausal women, using data from the Women's Health Initiative Observational Study (WHI-OS) and Clinical Trial (WHI-CT).

METHODS

The WHI study enrolled women aged 50-79 years from 1993 to 1998 at 40 US clinical centres. Among 146 326 participants with median 14.6 follow-up years, 23 067 incident cancers and 3152 cancer deaths were observed. Multivariable-adjusted Cox proportional hazards models were used to investigate the relationship between statin use and cancer survival.

RESULTS

Compared with never-users, current statin use was associated with significantly lower risk of cancer death (hazard ratio (HR), 0.78; 95% confidence interval (CI), 0.71-0.86, P<0.001) and all-cause mortality (HR, 0.80; 95% CI, 0.74-0.88). Use of other lipid-lowering medications was also associated with increased cancer survival (P-interaction (int)=0.57). The lower risk of cancer death was not dependent on statin potency (P-int=0.22), lipophilicity/hydrophilicity (P-int=0.43), type (P-int=0.34) or duration (P-int=0.33). However, past statin users were not at lower risk of cancer death compared with never-users (HR, 1.06; 95% CI, 0.85-1.33); in addition, statin use was not associated with a reduction of overall cancer incidence despite its effect on survival (HR, 0.96; 95% CI, 0.92-1.001).

CONCLUSIONS

In a cohort of postmenopausal women, regular use of statins or other lipid-lowering medications was associated with decreased cancer death, regardless of the type, duration, or potency of statin medications used.

Tocilizumab unmasks a stage-dependent interleukin-6 component in statin-induced apoptosis of metastatic melanoma cells

The interleukin (IL)-6 inhibits the growth of early-stage melanoma cells, but not metastatic cells. Metastatic melanoma cells are susceptible to statin-induced apoptosis, but this is not clear for early-stage melanoma cells. This study aimed to investigate the IL-6 susceptibility of melanoma cells from different stages in the presence of simvastatin to overcome loss of growth arrest. ELISA was used to detect secreted IL-6 in human melanoma cells. The effects of IL-6 were measured by western blots for STAT3 and Bcl-2 family proteins. Apoptosis and proliferation were measured by caspase 3 activity, Annexin V staining, cell cycle analysis, and a wound-healing assay. Human metastatic melanoma cells A375 and 518A2 secrete high amounts of IL-6, in contrast to early-stage WM35 cells. Canonical IL-6 signaling is intact in these cells, documented by transient phosphorylation of STAT3. Although WM35 cells are highly resistant to simvastatin-induced apoptosis, coadministration with IL-6 enhanced the susceptibility to undergo apoptosis. This proapoptotic effect of IL-6 might be explained by a downregulation of Bcl-X_L, observed only in WM35 cells. Furthermore, the IL-6 receptor blocking antibody tocilizumab was coadministered and unmasked an IL-6-sensitive proportion in the simvastatin-induced caspase 3 activity of metastatic melanoma cells. These results confirm that simvastatin facilitates apoptosis in combination with IL-6. Although endogenous IL-6 secretion is sufficient in metastatic melanoma cells, exogenously added IL-6 is needed for WM35 cells. This effect may explain the failure of simvastatin to reduce melanoma incidence in clinical trials and meta-analyses.

Prospective analysis of association between statins and pancreatic cancer risk in the Women's Health Initiative

PURPOSE

To determine whether HMG-CoA reductase inhibitors (statins) are associated with a lower risk of pancreatic cancer.

METHODS

The population included 160,578 postmenopausal women enrolled in the Women's Health Initiative (WHI) in which 385 incident cases of pancreatic cancer were identified over an average of 8.69 (SD ±4.59) years. All diagnoses were confirmed by medical record and pathology review. Information on statin use and other risk factors was collected at baseline and during follow-up. Multivariable-adjusted hazards ratios (HRs) and 95 % confidence intervals (CIs) evaluating the relationship between prior statin use (at baseline only as well as in a time-dependent manner) and risk of pancreatic cancer were computed from Cox proportional hazards regression analyses after adjusting for appropriate confounders. We also evaluated the effect of statin type, potency, lipophilic status, and duration of use. All statistical tests were two-sided.

RESULTS

Statins were used at baseline by 12,243 (7.5 %) women. The annualized rate of pancreatic cancer in statin users and nonusers, respectively, was 0.0298 versus 0.0271 %. The multivariable-adjusted HR for statin users versus nonusers at baseline was 0.92 and 95 % CI 0.57-1.48. In a time-dependent model, the HR for low-potency statins was 0.46, 95 % CI 0.20-1.04. There was no significant effect seen by statin lipophilicity or duration of use.

CONCLUSIONS

There was no significant relationship between statins and pancreatic cancer risk in the WHI; however, there was a marginal inverse association noted for low-potency statins. Analyses of larger numbers of cases are needed to further explore this relationship.

Relation of statin use with non-melanoma skin cancer: prospective results from the Women's Health Initiative

BACKGROUND

The relationship between statin use and non-melanoma skin cancer (NMSC) is unclear with conflicting findings in literature. Data from the Women's Health Initiative (WHI) Observational Study and WHI Clinical Trial were used to investigate the prospective relationship between statin use and NMSC in non-Hispanic white (NHW) postmenopausal women.

METHODS

The WHI study enrolled women aged 50-79 years at 40 US centres. Among 133,541 NHW participants, 118,357 with no cancer history at baseline and complete medication/covariate data comprised the analytic cohort. The association of statin use (baseline, overall as a time-varying variable, duration, type, potency, lipophilicity) and NMSC incidence was determined using random-effects logistic regression models.

RESULTS

Over a mean of 10.5 years of follow-up, we identified 11,555 NMSC cases. Compared with participants with no statin use, use of any statin at baseline was associated with significantly increased NMSC incidence (adjusted odds ratio (ORadj) 1.21; 95% confidence interval (CI): 1.07-1.35)). In particular, lovastatin (OR 1.52; 95% CI: 1.08-2.16), simvastatin (OR 1.38; 95% CI: 1.12-1.69), and lipophilic statins (OR 1.39; 95% CI: 1.18-1.64) were associated with higher NMSC risk. Low and high, but not medium, potency statins were associated with higher NMSC risk. No significant effect modification of the statin-NMSC relationship was found for age, BMI, smoking, solar irradiation, vitamin D use, and skin cancer history.

CONCLUSIONS

Use of statins, particularly lipophilic statins, was associated with increased NMSC risk in postmenopausal white women in the WHI cohort. The lack of duration-effect relationship points to possible residual confounding. Additional prospective research should further investigate this relationship.

Autocrine secretion of 15d-PGJ2 mediates simvastatin-induced apoptotic burst in human metastatic melanoma cells

BACKGROUND AND PURPOSE

Despite new therapeutic approaches, metastatic melanomas still have a poor prognosis. Statins reduce low-density lipoprotein cholesterol and exert anti-inflammatory and anti-proliferative actions. We have recently shown that simvastatin triggers an apoptotic burst in human metastatic melanoma cells by the synthesis of an autocrine factor.

EXPERIMENTAL APPROACH

The current in vitro study was performed in human metastatic melanoma cell lines (A375, 518a2) and primary human melanocytes and melanoma cells. The secretome of simvastatin-stressed cells was analysed with two-dimensional difference gel electrophoresis and MS. The signalling pathways involved were analysed at the protein and mRNA level using pharmacological approaches and siRNA technology.

KEY RESULTS

Simvastatin was shown to activate a stress cascade, leading to the synthesis of 15-deoxy-12,14-PGJ2 (15d-PGJ2 ), in a p38- and COX-2-dependent manner. Significant concentrations of 15d-PGJ2 were reached in the medium of melanoma cells, which were sufficient to activate caspase 8 and the mitochondrial pathway of apoptosis. Inhibition of lipocalin-type PGD synthase, a key enzyme for 15d-PGJ2 synthesis, abolished the apoptotic effect of simvastatin. Moreover, 15d-PGJ2 was shown to bind to the fatty acid-binding protein 5 (FABP5), which was up-regulated and predominantly detected in the secretome of simvastatin-stressed cells. Knockdown of FABP5 abolished simvastatin-induced activation of PPAR-γ and amplified the apoptotic response.

CONCLUSIONS AND IMPLICATIONS

We characterized simvastatin-induced activation of the 15d-PGJ2 /FABP5 signalling cascades, which triggered an apoptotic burst in melanoma cells but did not affect primary human melanocytes. These data support the rationale for the pharmacological targeting of 15d-PGJ2 in metastatic melanoma.

Impact of cholesterol on disease progression

Cholesterol-rich microdomains (also called lipid rafts), where platforms for signaling are provided and thought to be associated with microbe-induced pathogenesis and lead to cancer progression. After treatment of cells with cholesterol disrupting or usurping agents, raft-associated proteins and lipids can be dissociated, and this renders the cell structure nonfunctional and therefore mitigates disease severity. This review focuses on the role of cholesterol in disease progression including cancer development and infectious diseases. Understanding the molecular mechanisms of cholesterol in these diseases may provide insight into the development of novel strategies for controlling these diseases in clinical scenarios.

Statin use and its effect on all-cause mortality of melanoma patients: a population-based Dutch cohort study

Preclinical data showed anticancer effects of statins in melanoma, but meta-analyses could not demonstrate a reduced melanoma incidence in statin users. Rather than preventing occurrence, statins might reduce growth and metastatic spread of melanomas and ultimately improve survival. In this population-based study, we investigated the relationship between statin use and survival of melanoma patients. Patients ≥18 years who were diagnosed with cutaneous melanoma (Breslow thickness >1 mm) and registered in the Eindhoven Cancer Registry and in PHARMO Database Network between 1 January 1998 and 31 December 2010 were eligible. The hazard ratio (HR) of all-cause mortality was calculated by employing adjusted time-dependent and time-fixed Cox proportional hazard models. Disease-specific survival was estimated by means of 3-year relative survival rates (RSR). A control cohort of randomly selected patients using statins from PHARMO Database Network matched on age and gender was used to compare RSR of statin users to the general population. After melanoma diagnosis, 171 of 709 patients used statins. Use of statins showed a nonsignificantly decreased hazard of death (adjusted HR 0.76, 95% confidence interval [CI] 0.50–1.61). After stratification for gender, male but not female statin users showed a favorable outcome compared to nonusers (HR 0.57, 95% CI 0.32–0.99; HR 1.22, 95% CI 0.62–2.38, respectively). Three-year RSR for male statin users tended to be higher than for nonusers (91% vs. 80.5%, P = 0.06), no differences were observed in women (87.1% vs. 92.5%, P = 0.76). Statin use was not associated with an improved survival of melanoma patients. The trend for better survival of male in contrast to female statin users warrants further research.

A randomized, double-blind, placebo-controlled phase II clinical trial of lovastatin for various endpoints of melanoma pathobiology

On the basis of large cardiovascular clinical trials of lipid-lowering agents that showed a considerable decrease in the incidence of primary melanomas in the active agent arm, we have carried out a randomized, double-blind clinical trial examining the impact of lovastatin on various biomarkers of melanoma pathogenesis. Subjects with at least two clinically atypical nevi were randomized to receive oral lovastatin or placebo for a 6-month period. Clinical, histopathologic, and molecular biomarkers were evaluated for change in the two groups. Eighty subjects were randomized, evaluable, and included in the analyses. Lovastatin showed no benefit in comparison with placebo in the primary endpoint of decreasing the level of histopathologic atypia, nor in any of the secondary endpoints of decreasing clinical atypia, impact on nevus number, nor in showing significant changes in any of the molecular biomarkers. There were no significant differences in adverse event profiles for lovastatin compared with placebo. The lovastatin arm did show a significant and considerable decrease in total serum cholesterol and serum low-density lipoprotein (LDL) levels compared with placebo, an expected result. This finding bolsters confidence in subject compliance. Given the results of this trial, it is concluded that if lovastatin were to lower the incidence of melanoma, it would appear not to be doing so by reversing atypia of precursor atypical nevi over the 6-month time frame studied. Further research into the pathogenesis of melanoma and in other potential chemopreventive agents is needed.

Statin use is not associated with reduced risk of skin cancer: a meta-analysis

Background:

There is contradictory evidence about the association between statin and skin cancer.

Methods:

Literature search in PubMed and Web of Science was undertaken up to June 2013. Pooled relative risk (RR) estimates and 95% confidence intervals (CIs) were calculated.

Result:

A total of 21 articles with 29 studies were identified. No association was found between statin and skin cancer among neither melanoma (RR, 0.94; 95% CI, 0.85–1.04) nor non-melanoma skin cancer (RR, 1.03; 95% CI, 0.90–1.19).

Conclusion:

Our meta-analysis does not support a potential role of statin use in the prevention of skin cancer.

Total serum cholesterol and cancer incidence in the Metabolic syndrome and Cancer Project (Me-Can)

OBJECTIVE

To investigate the association between total serum cholesterol (TSC) and cancer incidence in the Metabolic syndrome and Cancer project (Me-Can).

METHODS

Me-Can consists of seven cohorts from Norway, Austria, and Sweden including 289,273 male and 288,057 female participants prospectively followed up for cancer incidence (n = 38,978) with a mean follow-up of 11.7 years. Cox regression models with age as the underlying time metric were used to estimate hazard ratios (HR) and their 95% confidence intervals (CI) for quintiles of cholesterol levels and per 1 mmol/l, adjusting for age at first measurement, body mass index (BMI), and smoking status. Estimates were corrected for regression dilution bias. Furthermore, we performed lag time analyses, excluding different times of follow-up, in order to check for reverse causation.

RESULTS

In men, compared with the 1st quintile, TSC concentrations in the 5th quintile were borderline significantly associated with decreasing risk of total cancer (HR = 0.94; 95%CI: 0.88, 1.00). Significant inverse associations were observed for cancers of the liver/intrahepatic bile duct (HR = 0.14; 95%CI: 0.07, 0.29), pancreas cancer (HR = 0.52, 95% CI: 0.33, 0.81), non-melanoma of skin (HR = 0.67; 95%CI: 0.46, 0.95), and cancers of the lymph-/hematopoietic tissue (HR = 0.68, 95%CI: 0.54, 0.87). In women, hazard ratios for the 5th quintile were associated with decreasing risk of total cancer (HR = 0.86, 95%CI: 0.79, 0.93) and for cancers of the gallbladder (HR = 0.23, 95%CI: 0.08, 0.62), breast (HR = 0.70, 95%CI: 0.61, 0.81), melanoma of skin (HR = 0.61, 95%CI: 0.42, 0.88), and cancers of the lymph-/hematopoietic tissue (HR = 0.61, 95%CI: 0.44, 0.83).

CONCLUSION

TSC was negatively associated with risk of cancer overall in females and risk of cancer at several sites in both males and females. In lag time analyses some associations persisted, suggesting that for these cancer sites reverse causation did not apply.