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

Dyslipidemia, lipid-lowering agents and neuroendocrine neoplasms: new horizons

PURPOSE

Neuroendocrine neoplasms (NENs) are a heterogeneous group of malignancies originating from cells with a neuroendocrine phenotype. The complex relationship between lipid metabolism and cancer is gaining interest and a potential anti-cancer effect of lipid lowering agents is being considered. This review aims to discuss the current understanding and treatment of dyslipidaemia in NENs, focusing on the role of lipid lowering agents, including new therapeutic approaches, and future perspectives as possible tool in cancer prevention and tumor-growth control.

METHODS

We performed an electronic-based search using PubMed updated until December 2023, summarizing the available evidence both in basic and clinical research about lipid lowering agents in NENs.

RESULTS

Dyslipidemia is an important aspect to be considered in NENs management, although randomized studies specifically addressing this topic are lacking, unlike other cancer types. Available data mainly regard statins, and in vitro studies have demonstrated direct antitumor effects, including antiproliferative effects in some cancers, supporting possible pleiotropic effects also in NENs, but data remain conflicting. Ezetimibe, omega 3-fatty acids, fibrates and inhibitors of proprotein convertase subtilisin/kexin type 9 (PCSK9) may enhance the regulation of lipid homeostasis, as demonstrated in other cancers.

CONCLUSIONS

Targeting dyslipidemia in NENs should be part of the multidisciplinary management and an integrated approach may be the best option for both metabolic and tumor control. Whether lipid lowering agents may directly contribute to tumor control remains to be confirmed with specific studies, focusing on association with other metabolic risk, disease stage and primary site.

Impact of statin on renal cell carcinoma patients undergoing nephrectomy. Does it affect cancer progression and improves survival? A Systematic Review and Meta-Analysis

INTRODUCTION

Renal cell carcinoma (RCC) is regarded as one of the most common malignant tumors. Various concomitant medications in RCC patients undergoing surgery are investigated to explore the potential for improving survival and preventing disease recurrence, including statin. It has been observed that these drugs induce apoptosis, thereby inhibiting tumor growth and angiogenesis. We aimed to perform a systematic review and meta-analysis to enhance the level of evidence for statin in RCC.

METHODS

A systematic literature search was conducted in several online databases, including PubMed, Scopus, and Sciencedirect, using terms relevant to the use of statins in RCC patients undergoing nephrectomy for publications published up to July 2023, according to a registered review procedure (CRD42023452318). The Newcastle-Ottawa Scale (NOS) was used to assess the risk of bias of the included study. Review Manager 5.4 was used for all analyses.

RESULTS

Seven articles was eligible for our study. The analysis revealed that patients receiving statin had a better overall survival compared to patients who does not receive statin (HR 0.71, 95% CI 0.51-0.97, p = 0.03, I2 = 76%). However, there was insignificant difference in terms of CSS, DFS, and PFS between RCC patients receiving statin and without statin.

CONCLUSIONS

Statin has substantial benefits for improving OS. Even though the outcomes for CSS, DFS, and PFS were insignificant, the potential role of statins as a supplementary therapy in surgically treated RCC still requires further investigation.

Gypenosides suppress hepatocellular carcinoma cells by blocking cholesterol biosynthesis through inhibition of MVA pathway enzyme HMGCS1

Hepatocellular carcinoma (HCC) is one of the most common malignant tumors with high morbidity and mortality. Targeting abnormal cholesterol metabolism is a potential therapeutic direction. Therefore, more natural drugs targeting cholesterol in HCC need to be developed. Gypenosides (Gyp), the major constituent of Gynostemma pentaphyllum, has been demonstrated to have pharmacological properties on anti-cancer, anti-obesity, and hepatoprotective. We investigated whether Gyp, isolated and purified by our lab, could inhibit HCC progression by inhibiting cholesterol synthesis. The present research showed that Gyp inhibited proliferation and migration, and induced apoptosis in Huh-7 and Hep3B cells. Metabolomics, transcriptomics, and target prediction all suggested that lipid metabolism and cholesterol biosynthesis were the mechanisms of Gyp. Gyp could limit the production of cholesterol and target HMGCS1, the cholesterol synthesis-related protein. Downregulation of HMGCS1 could suppress the progression and abnormal cholesterol metabolism of HCC. In terms of mechanism, Gyp suppressed mevalonate (MVA) pathway mediated cholesterol synthesis by inhibiting HMGCS1 transcription factor SREBP2. And the high expression of HMGCS1 in HCC human specimens was correlated with poor clinical prognosis. The data suggested that Gyp could be a promising cholesterol-lowering drug for the prevention and treatment of HCC. And targeting SREBP2-HMGCS1 axis in MVA pathway might be an effective HCC therapeutic strategy.

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.

Lipids as Targets for Renal Cell Carcinoma Therapy

Kidney cancer is among the top ten most common cancers to date. Within the kidney, renal cell carcinoma (RCC) is the most common solid lesion occurring. While various risk factors are suspected, including unhealthy lifestyle, age, and ethnicity, genetic mutations seem to be a key risk factor. In particular, mutations in the von Hippel-Lindau gene (Vhl) have attracted a lot of interest since this gene regulates the hypoxia inducible transcription factors HIF-1α and HIF-2α, which in turn drive the transcription of many genes that are important for renal cancer growth and progression, including genes involved in lipid metabolism and signaling. Recent data suggest that HIF-1/2 are themselves regulated by bioactive lipids which make the connection between lipids and renal cancer obvious. This review will summarize the effects and contributions of the different classes of bioactive lipids, including sphingolipids, glycosphingolipids, eicosanoids, free fatty acids, cannabinoids, and cholesterol to renal carcinoma progression. Novel pharmacological strategies interfering with lipid signaling to treat renal cancer will be highlighted.

Statin drugs enhance responses to immune checkpoint blockade in head and neck cancer models

BACKGROUND

Anti-PD-1 immune checkpoint blockade is approved for first-line treatment of recurrent/metastatic head and neck squamous cell carcinoma (HNSCC), but few patients respond. Statin drugs (HMG-CoA reductase inhibitors) are associated with superior survival in several cancer types, including HNSCC. Emerging data suggest that manipulation of cholesterol may enhance some aspects of antitumor immunity.

METHODS

We used syngeneic murine models (mouse oral cancer, MOC1 and TC-1) to investigate our hypothesis that a subset of statin drugs would enhance antitumor immunity and delay tumor growth.

RESULTS

Using an ex vivo coculture assay of murine cancer cells and tumor infiltrating lymphocytes, we discovered that all seven statin drugs inhibited tumor cell proliferation. Simvastatin and lovastatin also enhanced T-cell killing of tumor cells. In mice, daily oral simvastatin or lovastatin enhanced tumor control and extended survival when combined with PD-1 blockade, with rejection of MOC1 tumors in 30% of mice treated with lovastatin plus anti-PD-1. Results from flow cytometry of tumors and tumor-draining lymph nodes suggested T cell activation and shifts from M2 to M1 macrophage predominance as potential mechanisms of combination therapy.

CONCLUSIONS

These results suggest that statins deserve further study as well-tolerated, inexpensive drugs that may enhance responses to PD-1 checkpoint blockade and other immunotherapies for HNSCC.

The tumor-repressing effect of CYP27A1 on renal cell carcinoma by 27-HC arising from cholesterol metabolism

As a key approach to mediate cholesterol metabolism, the role of the CYP27A1/27-HC axis in renal cell carcinoma (RCC) remains unclear. Analysis of CYP27A1 expression from public databases and metastatic cases in our center suggested that CYP27A1 was obviously downregulated in RCC tissues, and survival analysis further showed its correlation with favorable clinicopathological features and prognosis. In vitro, up and downregulation of CYP27A1 expression in RCC cell lines could definitely illustrate its anticipation involving apoptosis, proliferation, invasion, migration, and clonality. This could be achieved through upregulation of 27-HC concentration, which mediates the activation of signaling pathways of apoptosis and cell cycle arrest. Further, recovery of CYP27A1 expression could definitely inhibit the proliferation of RCC tumors in vivo. This is the first study to explore the role of the CYP27A1/27-HC axis in RCC. Attempts to maintain the normal function of the axis may be a potential strategy in the treatment of RCC, and the predictive value of CYP27A1 detection on the efficacy of targeted therapy in metastatic RCC is also worthy of attention.