Association of statin use on survival outcomes of patients with early-stage HER2-positive breast cancer in the APHINITY trial

PURPOSE

There is evidence that statins might improve the outcome of patients with breast cancer. The role of statins in patients with early HER2-positive breast cancer is unknown. Therefore, we explored the association between statin use and survival outcomes in early HER2-positive breast cancer patients in the phase III APHINITY trial (adjuvant pertuzumab/trastuzumab).

METHODS

All patients (intent-to-treat population, n = 4804) were included (6.2 years median follow-up database). The primary objective was to investigate the association of statin use on invasive disease-free survival (IDFS), distant relapse-free interval (DRFI), and overall survival (OS). Patients who received statins at baseline, or started statins within 1 year from randomization were considered statin users. Survival curves were estimated using the Kaplan-Meier method. We used a Cox proportional hazards model for multivariate analysis.

RESULTS

Overall, 423 (8.8%) patients were classified as statin users. They were older, more often postmenopausal, had a higher body mass index, more often diabetes, hypertension, coronary heart disease and hyperlipidemia, had smaller sized tumors, were treated more often with breast conserving surgery, and less often with anthracycline-containing regimens. Overall, 508 IDFS events (12.8% among statin users and 10.4% among non-statin users) and 272 deaths (8.5% and 5.4%, respectively) occurred. In multivariate analysis, statin use was not associated with IDFS (HR, 1.11; 95% CI, 0.80-1.52), DRFI (HR, 1.21; 95% CI, 0.81-1.81) nor OS (HR, 1.16; 95% CI, 0.78-1.73).

CONCLUSION

In APHINITY, statin use was not associated with improved survival outcomes. These results must be interpreted with caution due to the exploratory nature of the analysis and the associated limitations.

Statins and prognosis of female breast cancer: a meta-analysis

BACKGROUND

Breast cancer (BC) incidence is estimated to achieve over 3-million new cases and one million deaths by 2040. Beyond its physical toll, breast cancer detrimentally affects quality of life, imposing emotional, social, and financial burdens on patients and their families. Statins, commonly prescribed for managing cardiovascular health, have garnered attention for their potential role in breast cancer management. Emerging evidence suggests that statins possess anti-proliferative properties, which could impact BC progression. Understanding the potential benefits of statin therapy in BC patients is crucial for optimizing treatment strategies and improving outcomes.

METHODS

Hazard ratio (HR) with 95% confidence intervals (CIs) were calculated to evaluate the outcomes. The DerSimonian and Laird random-effects model was used for all pooled analyses. Heterogeneity was assessed using the I2 statistic with corresponding 95% CIs, considering I2 > 25% as indicative of substantial heterogeneity. Statistical analyses were conducted in R (version 4.3.2) using the "meta" package, with a significance level set at P < 0.05.

RESULTS

A total of 31 studies and 344,936 patients were included, of whom 72,784 (21.1%) was in the statins group and 272,152 (78.9%) was in the non-statin users group. Statin therapy was associated with a significantly reduced risks of all-cause mortality (HR 0.8583; 95% CI 0.7980-0.9231; P < 0.001; I2 = 81.1%), of BCSM (HR 0.8183; 95% CI 0.7334-0.9132; P < 0.001; I2 = 84.4%), and of BC recurrence (HR 0.7911; 95% CI 0.6882-0.9095; P < 0.001; I2 = 48.6%). However, the analysis of DFS did not show a statistically significant difference between the groups (HR 0.8415; 95% CI 0.4220-1.6780; P = 0.624; I2 = 74.2%).

CONCLUSION

Our meta-analysis suggests that statin therapy may confer beneficial effects on clinical outcomes in female breast cancer patients, including reduced all-cause mortality, breast cancer-specific mortality, and recurrence. However, further research is warranted to confirm these findings and elucidate the mechanisms underlying these associations.

Genetic association of lipids and lipid-lowering drug target genes with breast cancer

BACKGROUND

Although several preclinical and epidemiological studies have shown that blood lipids and lipid-lowering drugs can reduce the risk of breast cancer, this finding remains controversial. This study aimed to explore the causal relationship between dyslipidemia,lipid-lowering drugs, and breast cancer. We also aimed to evaluate the potential impact of lipid-lowering drug targets on breast cancer.

METHOD

Data of 431 lipid- and lipid-related phenotypes were obtained from genome-wide association study (GWAS), and mendelian randomization (MR) analyses were performed using two independent breast cancer datasets as endpoints. Genetic variants associated with genes encoding lipid-lowering drug targets were extracted from the Global Lipid Genetics Consortium. Expression quantitative trait loci data in relevant tissues were used to further validate lipid-lowering drug targets that reached significance and combined with bioinformatics approaches for molecular expression and prognostic exploration. Further mediation analyses were performed to explore potential mediators.

RESULT

In two independent datasets, phosphatidylcholine (18:1_0:0 levels) was associated with breast cancer risk (discovery: odds ratio (OR) = 1.255 [95% confidence interval (CI) 1.120-1.406]; p = 8.936 × 10-5, replication: OR = 1.016 [95% CI, 1.003-1.030]; p = 0.017), HMG- CoA reductase (HMGCR) inhibition was genetically modeled and associated with a reduced risk of breast cancer (discovery: OR = 0.833 [95% CI 0.752-0.923], p = 5.12 × 10-4; replication: OR = 0.975 [95% CI 0.960-0.990], p = 1.65 × 10-3). There was a significant MR correlation between HMGCR expression in whole blood and breast cancer (OR = 1.11 [95% 1.01-1.22] p = 0.04). Bioinformatics analysis revealed that HMGCR expression higher in breast cancer tissues than in normal tissues, along with poor overall survival and relapse-free survival, and was associated with multiple immune cell infiltration. Finally, the mediation analysis showed that HMGCR inhibitors affected breast cancer through different immune cell phenotypes and C-reactive protein levels.

CONCLUSION

In this study, we found for the first time that phosphatidylcholine (18:1_0:0) levels are associated with breast cancer risk. We found that HMGCR inhibitors are associated with a reduced risk of breast cancer, and part of their action may be through pathways other than lipid-lowering, including modulation of immune function and reduction of inflammation represented by C-reactive protein levels.

SNAI2, a potential crossing point between cancer and cardiovascular disease

Cancer and cardiovascular disease remain the leading causes of morbidity and mortality worldwide, and the two separate disease entities share several similarities and possible interactions. Patients with cancer may have underlying cardiovascular disease, which is often exacerbated by the stress of tumor growth or treatment. At the same time, cardiotoxicity induced by anti-cancer therapies or the malignant process itself can lead to new cardiovascular diseases. Efforts have been made to find a rational explanation for this phenomenon. As a classical tumor-promoting factor, we notice that SNAI2 simultaneously plays an important pathogenic role in cardiovascular diseases. Moreover, there are several striking parallels in the mechanisms of cancer and CVD, such as shared risk factors (e.g., smoking and diabetes), cellular phenotypic switching, and metabolic remodeling, all of which are mediated by SNAI2. This review aims to summarize SNAI2's role in the core mechanisms linking cancer and CVD, as well as explore therapeutic approaches targeting SNAI2 and also seeks to provide insights into the common mechanisms underlying both cancer and CVD.

Dual Inhibition of CDK4/6 and CDK7 Suppresses Triple-Negative Breast Cancer Progression via Epigenetic Modulation of SREBP1-Regulated Cholesterol Metabolism

Inhibitors targeting cyclin-dependent kinases 4 and 6 (CDK4/6) to block cell cycle progression have been effective in treating hormone receptor-positive breast cancer, but triple-negative breast cancer (TNBC) remains largely resistant, limiting their clinical applicability. The study reveals that transcription regulator cyclin-dependent kinase7 (CDK7) is a promising target to circumvent TNBC's inherent resistance to CDK4/6 inhibitors. Combining CDK4/6 and CDK7 inhibitors significantly enhances therapeutic effectiveness, leading to a marked decrease in cholesterol biosynthesis within cells. This effect is achieved through reduced activity of the transcription factor forkhead box M1 (FOXM1), which normally increases cholesterol production by inducing SREBF1 expression. Furthermore, this dual inhibition strategy attenuates the recruitment of sterol regulatory element binding transcription factor 1 (SREBP1) and p300 to genes essential for cholesterol synthesis, thus hindering tumor growth. This research is corroborated by an in-house cohort showing lower survival rates in TNBC patients with higher cholesterol production gene activity. This suggests a new treatment approach for TNBC by simultaneously targeting CDK4/6 and CDK7, warranting additional clinical trials.

Targeting piRNA-137463 Inhibits Tumor Progression and Boosts Sensitivity to Immune Checkpoint Blockade via De Novo Cholesterol Biosynthesis in Lung Adenocarcinoma

The important role of PIWI-interacting RNAs (piRNAs) in tumors has garnered increasing attention. However, research on their role in lung adenocarcinoma (LUAD) remains limited. Elevated levels of piRNA-137463 have been linked to poor prognosis in LUAD patients. Inhibition of piRNA-137463 curbed the proliferation, migration, and invasion of LUAD cells, enhanced T cell cytotoxicity through increased IFN-γ secretion, disrupted cholesterol metabolism, and reduced intracellular cholesterol, lipid raft content, and PD-L1 expression in LUAD cells. Bioinformatic prediction identified a potential interaction between piRNA-137463 and lncRNA LOC100128494. Inhibiting piRNA-137463 increased the stability and expression of LOC100128494, which further modulated insulin-induced gene 1 protein (INSIG1) levels via a competitive endogenous RNA network involving LOC100128494 and miR-24-3p. Notably, the effect of piRNA-137463 in LUAD cells is dependent on the expression of LOC100128494 and INSIG1. Inhibiting the expression of piRNA-137463 with AntagopiRNA-137463 suppressed tumor growth and metastasis via LOC100128494 in nude mice and enhanced the response of LUAD to anti-PD-1 therapy in immune-competent mice. In summary, this study elucidates the role of piRNA-137463 in the reprogramming of cholesterol metabolism, which drives the progression of LUAD, thereby identifying a new target for the comprehensive clinical management of LUAD.

Tetramethylpyrazine attenuates the cancer stem cell like-properties and doxorubicin resistance by targeting HMGCR in breast cancer

BACKGROUND

Tetramethylpyrazine (TMP), a key bioactive constituent derived from Ligusticum wallichii Franchat, has demonstrated efficacy in mitigating multidrug resistance (MDR) in human breast cancer (BC) cells. However, the precise mechanisms underlying its action remain poorly understood.

PURPOSE

Cancer stem cells (CSCs) are widely recognized as the primary contributors to MDR. This investigation seeks to elucidate the role and mechanisms through which TMP counteracts MDR by attenuating CSC-like characteristics.

METHODS

Various assays, including flow cytometry, sphere formation, and Western blotting, were employed to evaluate TMP's effects on breast cancer stem cell (BCSC)-like phenotypes in vitro. In vivo, extreme limiting dilution assays and immunohistochemistry (IHC) were executed to assess the impacts of TMP on BCSC frequency and the levels of stemness markers. Mechanistically, RNA sequencing was performed to uncover the key biological processes involved in TMP's effects on BCSCs. Further experiments, encompassing micro scale thermophoresis (MST), drug affinity responsive target stability (DARTS), cellular thermal shift assay (CETSA) and amino acid mutation analyses, were utilized to identify the essential targets and corresponding binding sites of TMP. Finally, the effects of TMP on BCSC-like phenotypes were confirmed using cells with mutated amino acid residues, which allowed us to investigate the specificity of TMP's binding sites. To further evaluate the impact of TMP on drug resistance, doxorubicin-resistant MCF7 (MCF-7ADR) cells, along with corresponding cell lines harboring mutated amino acid residues, were employed.

RESULTS

TMP was found to inhibit BCSC-like properties both in vitro and in vivo, evidenced by a reduction in the CD44+/CD24- population, sphere formation capability, and expression of stemness markers. Mechanistic studies revealed that TMP targets 3‑hydroxy-3-methylglutaryl-CoA reductase (HMGCR), a rate-limiting enzyme in cholesterol biosynthesis. TMP binds to Asp-767 of HMGCR, thereby inhibiting its activity and reducing cholesterol synthesis. The influence of TMP on BCSC-like phenotypes was nullified by overexpression of wild-type HMGCR, while mutations in the binding site of HMGCR had no effect on TMP's inhibition of BCSC-like properties. Additionally, TMP mitigated MDR by targeting HMGCR.

CONCLUSION

These findings suggest that TMP alleviates MDR by reducing BCSC-like traits through targeting HMGCR and disruption of cholesterol biosynthesis in BC. This provides new insights into the mechanisms through which TMP alleviates MDR and offers new lead compound for exploring HMCGR antagonists.

Exposure to air pollutants and breast cancer risk: mediating effects of metabolic health biomarkers in a nested case-control study within the E3N-Generations cohort

BACKGROUND

Growing epidemiological evidence suggests an association between exposure to air pollutants and breast cancer. Yet, the underlying mechanisms remain poorly understood. This study explored the mediating role of thirteen metabolic health biomarkers in the relationship between exposure to three air pollutants, i.e. nitrogen dioxide (NO2), polychlorinated biphenyls 153 (PCB153), and benzo[a]pyrene (BaP), and breast cancer risk.

METHODS

We used data from a nested case-control study within the French national prospective E3N-Generations cohort, involving 523 breast cancer cases and 523 matched controls. The four-way decomposition mediation of total effects for thirteen biomarkers was applied to estimate interaction and mediation effects (controlled direct, reference interaction, mediated interaction, and pure indirect effects).

RESULTS

The analyses indicated a significant increase in breast cancer risk associated with BaP exposure (odds ratio (OR)Q4 vs Q1 = 2.32, 95% confidence intervals (CI): 1.00-5.37). PCB153 exposure showed a positive association only in the third quartile (ORQ3 vs Q1 = 2.25, CI 1.13-4.57), but it appeared to be non-significant in the highest quartile (ORQ4 vs Q1 = 2.07, CI 0.93-4.61). No association was observed between NO2 exposure and breast cancer risk. Estradiol was associated with an increased risk of breast cancer (OR per one standard deviation (SD) increment = 1.22, CI 1.05-1.42), while thyroid-stimulating hormone was inversely related to breast cancer risk (OR per 1SD increase = 0.87, CI 0.75-1.00). We observed a suggestive mediated effect of the association between the three pollutants and breast cancer risk, through albumin, high-density lipoproteins cholesterol, low-density lipoprotein cholesterol, parathormone, and estradiol.

CONCLUSION

Although limited by a lack of statistical power, this study provides relevant insights into the potential mediating role of certain biomarkers in the association between air pollutant exposure and breast cancer risk, highlighting the need for further in-depth studies in large populations.

The effect of tamoxifen as an adjuvant therapy for breast cancer on apolipoproteins and lipoprotein(a) concentrations in women: A meta-analysis of randomized controlled trials

BACKGROUND AND AIM

Tamoxifen has been used in the management of breast cancer. The available evidence on the effect of tamoxifen on lipoprotein(a) and apolipoproteins is controversial. Hence, this meta-analysis of randomized controlled trials (RCTs) was conducted to increase the quality of evidence on the effect of tamoxifen on lipoprotein(a) and apolipoproteins.

METHODS

Eligible RCTs published up to September 2023 were carefully selected following a comprehensive search. Thereafter, a meta-analysis was conducted using a random-effects model and the results were presented as the weighted mean difference (WMD) with a 95 % confidence interval (CI).

RESULTS

The results from the random-effects model indicated a rise in ApoA-I (WMD: 16.24 mg/dL, 95 % CI: 5.35, 27.12, P = 0.003), and a decrease in ApoB (WMD: -9.37 mg/dL, 95 % CI: -15.16, -3.59, P = 0.001) and lipoprotein(a) (WMD: -3.24 mg/dL, 95 % CI: -5.66, -0.83, P < 0.001) concentrations following tamoxifen administration in women. Furthermore, a more pronounced decrease in ApoB (WMD: -12.86 mg/dL, 95 % CI: -19.78, -5.93, P < 0.001) and elevation in ApoA-1 levels (WMD: 51.97 mg/dL, 95 % CI: 45.89, 58.05, P < 0.001) were identified in a single study on patients with breast cancer.

CONCLUSION

The current meta-analysis demonstrated an increase of ApoA-I and a decrease of ApoB and lipoprotein(a) levels after treatment with tamoxifen in women.

Fluctuations in serum lipid levels during neoadjuvant treatment as novel predictive and prognostic biomarkers for locally advanced breast cancer: a retrospective analysis based on a prospective cohort

BACKGROUND

With increasing attention given to host-specific lipid metabolism status, it is of urgent need to identify lipid metabolism indices with predictive or prognostic value in locally advanced breast cancer patients treated with neoadjuvant chemotherapy (NAC), and to evaluate the performance improvement by incorporating them into the existing Neo-Bioscore staging system.

METHODS

Patients from a prospectively maintained database of locally advanced breast cancer patients who received radical surgery after NAC between January 2014 to December 2020 were enrolled in this study. The enrolled patients were randomly divided into a training set and a test set at a ratio of 6:4. The random forest algorithm was applied to rank the importance of prognostic factors, top-ranked lipid metabolism indices of which were then incorporated into Neo-Bioscore to construct an updated prognostic model. The performances of these two models were compared in both training set and test set from multiple perspectives. Study outcomes included disease-free survival (DFS), relapse-free survival (RFS), distance-recurrence-free survival (DRFS), locoregional-recurrence-free survival (LRFS) and overall survival (OS).

RESULTS

A total of 200 eligible patients were included in this study. After a median follow-up of 4.73 years, it was demonstrated that the relative increase in total cholesterol (TC; DFS: HR = 4.782, 95%CI 1.410 ~ 16.217, P = 0.012) and low-density lipoprotein (LDL; DFS: HR = 4.622, 95%CI 1.517 ~ 14.088, P = 0.007) during NAC led to poorer survival outcomes. Patients with either a higher body mass index (BMI) or elevated LDL during NAC had a worse prognosis (DFS: HR = 6.351, 95%CI 1.938 ~ 20.809, P = 0.002; OS, HR = 6.919, 95%CI 1.296 ~ 36.932, P = 0.024). Incorporating BMI and LDL fluctuations during NAC into Neo-Bioscore improved the prognostic stratification, especially in terms of LRFS (P = 0.046 vs. P = 0.65) and OS (P = 0.013 vs. P = 0.61). Multidimensional evaluation confirmed the improvement in model fit and clinical use for the updated model in both training set and test set.

CONCLUSIONS

This is the first study to illustrate the relative elevation of LDL and TC levels during NAC as independent prognosticators for locally advanced breast cancer. This is also the first attempt to incorporate lipid metabolism indices into the original Neo-Bioscore staging system, which further improves the prognostic stratification of patients receiving NAC.

Serum lipid ratios as novel prognostic biomarkers for patients with locally advanced breast cancer treated with neoadjuvant therapy

OBJECTIVES

To investigate the association between lipid ratios and survival outcomes in patients with locally advanced breast cancer (LABC) undergoing neoadjuvant chemotherapy.

METHOD

This retrospective study included patients with LABC receiving neoadjuvant chemotherapy. Serum lipid levels were prospectively measured at baseline. Associations of triglyceride to total cholesterol (TG/TC), triglyceride to high-density lipoprotein (TG/HDL) and triglyceride to low-density lipoprotein (TG/LDL) ratios with prognosis were evaluated.

RESULTS

Patients with high TG/TC (adjusted hazard ratio [aHR] = 2.47, 95% CI: 1.10, 5.56, p = 0.029), TG/HDL (aHR = 2.73, 95% CI: 1.16, 6.41, p = 0.021) and TG/LDL (aHR = 2.50, 95% CI: 1.11, 5.65, p = 0.027) ratios were more likely to experience disease-free survival (DFS) events. Subgroup analysis suggested that the prognostic impact of lipid ratios was more pronounced in patients with negative HER2 status or those at a high risk of recurrence (e.g. clinical stage III, Ki67 > 30%). Additionally, higher lipid ratios tended to indicate early DFS events (0 ~ 2 years) (TG/TC p = 0.021, TG/HDL p = 0.046, TG/LDL p < 0.001), and the TG/LDL ratio demonstrated the best predictive efficacy (TG/TC vs. TG/HDL vs. TG/LDL, 1-year AUC: 0.724 vs. 0.676 vs. 0.846, 2-year AUC: 0.653 vs. 0.638 vs. 0.708).

CONCLUSION

Baseline serum TG/TC, TG/HDL and TG/LDL ratios were independent prognostic factors in patients with LABC undergoing neoadjuvant therapy. However, their utility in predicting the early DFS events warrants further investigation.

CLINICAL TRIAL REGISTRATION

NCT05621564.

Inhibition of tumor migration and invasion by fenofibrate via suppressing epithelial-mesenchymal transition in breast cancers

The recurrence and metastasis in breast cancer within 3 years after the chemotherapies or surgery leads to poor prognosis with approximately 1-year overall survival. Large-scale scanning research studies have shown that taking lipid-lowering drugs may assist to reduce the risk of death from many cancers, since cholesterol in lipid rafts are essential for maintain integral membrane structure and functional signaling regulation. In this study, we examined five lipid-lowering drugs: swertiamarin, gemfibrozil, clofibrate, bezafibrate, and fenofibrate in triple-negative breast cancer, which is the most migration-prone subtype. Using human and murine triple-negative breast cancer cell lines (Hs 578 t and 4 T1), we found that fenofibrate displays the highest potential in inhibiting the colony formation, wound healing, and transwell migration. We further discovered that fenofibrate reduces the activity of pro-metastatic enzymes, matrix metalloproteinases (MMP)-9 and MMP-2. In addition, epithelial markers including E-cadherin and Zonula occludens-1 are increased, whereas mesenchymal markers including Snail, Twist and α-smooth muscle actin are attenuated. Furthermore, we found that fenofibrate downregulates ubiquitin-dependent GDF-15 degradation, which leads to enhanced GDF-15 expression that inhibits cell migration. Besides, nuclear translocation of FOXO1 is also upregulated by fenofibrate, which may responsible for GDF-15 expression. In summary, fenofibrate with anti-cancer ability hinders TNBC from migration and invasion, and may be beneficial to repurposing use of fenofibrate.

Impact of De Novo Cholesterol Biosynthesis on the Initiation and Progression of Breast Cancer

Cholesterol (CHOL) is a multifaceted lipid molecule. It is an essential structural component of cell membranes, where it cooperates in regulating the intracellular trafficking and signaling pathways. Additionally, it serves as a precursor for vital biomolecules, including steroid hormones, isoprenoids, vitamin D, and bile acids. Although CHOL is normally uptaken from the bloodstream, cells can synthesize it de novo in response to an increased requirement due to physiological tissue remodeling or abnormal proliferation, such as in cancer. Cumulating evidence indicated that increased CHOL biosynthesis is a common feature of breast cancer and is associated with the neoplastic transformation of normal mammary epithelial cells. After an overview of the multiple biological activities of CHOL and its derivatives, this review will address the impact of de novo CHOL production on the promotion of breast cancer with a focus on mammary stem cells. The review will also discuss the effect of de novo CHOL production on in situ and invasive carcinoma and its impact on the response to adjuvant treatment. Finally, the review will discuss the present and future therapeutic strategies to normalize CHOL biosynthesis.

Comparison of the effects of high-intensity interval and moderate-intensity continuous training on inflammatory markers, cardiorespiratory fitness, and quality of life in breast cancer patients

BACKGROUND

As the effectiveness of breast cancer treatment has improved, a growing number of long-term breast cancer survivors are seeking help for unique health problems. These patients may be at increased risk of cardiovascular disease due to the side effects of treatment. The positive impact of most types of exercise has been repeatedly reported in people with cancer, but the most effective exercise approaches for maximum beneficial adaptations remain controversial. Thus, this study aimed to compare the effects of high-intensity interval training (HIIT) and moderate-intensity continuous training (MICT) on inflammatory indices, adipokines, metabolic markers, body composition, cardiorespiratory fitness, and quality of life in breast cancer patients during adjuvant endocrine therapy.

METHODS

Thirty non-metastatic breast cancer patients during adjuvant endocrine therapy who had been treated with chemotherapy and/or radiotherapy were recruited from Iran and randomized to HIIT, MICT, or control groups for a supervised exercise intervention that took place 3 times a week for 12 weeks. The training intensity was determined based on the peak oxygen uptake (VO2peak), and the volume of training was matched in HIIT and MICT based on the VO2peak. Body composition, functional capacity, cardiorespiratory fitness, metabolic indices, sex hormones, adipokines, and inflammatory markers were assessed before and after the intervention.

RESULTS

The VO2peak increased by 16.8% in the HIIT group in comparison to baseline values (mean difference = 3.61 mL/kg/min). HIIT significantly improved the VO2peak compared to control (mean difference = 3.609 mL/kg/min) and MICT (mean differences = 2.974 mL/kg/min) groups. Both HIIT (mean difference = 9.172 mg/dL) and MICT (mean difference = 7.879 mg/dL) interventions significantly increased high-density lipoprotein cholesterol levels compared to the control group. The analysis of covariance showed that physical well-being significantly improved in MICT compared to control group (mean difference = 3.268). HIIT significantly improved the social well-being compared to the control group (mean difference = 4.412). Emotional well-being subscale was significantly improved in both MICT (mean difference = 4.248) and HIIT (mean difference = 4.412) compared to the control group. Functional well-being scores significantly increased in HIIT group compared with control group (mean difference = 3.35) . Significant increase were also observed in total functional assessment of cancer therapy-General scores in both HIIT (mean difference = 14.204) and MICT groups (mean difference = 10.036) compared with control group. The serum level of suppressor of cytokine signaling 3 increased significantly (mean difference = 0.09 pg/mL) in the HIIT group compared to the baseline. There were no significant differences between groups for body weight, body mass index, fasting blood glucose, insulin resistance, sex hormone binding globulin, total cholesterol, low-density lipoprotein cholesterol, adipokines, interleukin-6, tumor necrosis factor-α, or interleukin-10.

CONCLUSION

HIIT can be used as a safe, feasible, and time-efficient intervention to improve cardiovascular fitness in breast cancer patients. Both HIIT and MICT modalities enhance quality of life. Further large-scale studies will help determine whether these promising results translate into improved clinical and oncological outcomes.

Is cholesterol a risk factor for breast cancer incidence and outcome?

Cholesterol plays important roles in many physiological processes, including cell membrane structure and function, hormone synthesis, and the regulation of cellular homeostasis. The role of cholesterol in breast cancer is complex, and some studies have suggested that elevated cholesterol levels may be associated with an increased risk of developing breast cancer, while others have found no significant association. On the other hand, other studies have shown that, for total cholesterol and plasma HDL-associated cholesterol levels, there was inverse association with breast cancer risk. One possible mechanism by which cholesterol may contribute to breast cancer risk is as a key precursor of estrogen. Other potential mechanisms by which cholesterol may contribute to breast cancer risk include its role in inflammation and oxidative stress, which have been linked to cancer progression. Cholesterol has also been shown to play a role in signaling pathways regulating the growth and proliferation of cancer cells. In addition, recent studies have shown that cholesterol metabolism can generate tumor promoters such as cholesteryl esters, oncosterone, 27-hydroxycholesterol but also tumor suppressor metabolites such as dendrogenin A. This review summarizes some of the most important clinical studies that have evaluated the role of cholesterol or its derivatives in breast cancer. It also addresses the role of cholesterol and its derivatives at the cellular level.

The Molecular and Genetic Interactions between Obesity and Breast Cancer Risk

Breast cancer (BC) is considered the leading cause of death among females worldwide. Various risk factors contribute to BC development, such as age, genetics, reproductive factors, obesity, alcohol intake, and lifestyle. Obesity is considered to be a pandemic health problem globally, affecting millions of people worldwide. Obesity has been associated with a high risk of BC development. Determining the impact of obesity on BC development risk in women by demonstrating the molecular and genetic association in pre- and post-menopause females and risk to BC initiation is crucial in order to improve the diagnosis and prognosis of BC disease. In epidemiological studies, BC in premenopausal women was shown to be protective in a certain pattern. These altered effects between the two phases could be due to various physiological changes, such as estrogen/progesterone fluctuating levels. In addition, the relationship between BC risk and obesity is indicated by different molecular alterations as metabolic pathways and genetic mutation or epigenetic DNA changes supporting a strong connection between obesity and BC risk. However, these molecular and genetic alteration remain incompletely understood. The aim of this review is to highlight and elucidate the different molecular mechanisms and genetic changes occurring in obese women and their association with BC risk and development.

Regulation of intrinsic and extrinsic metabolic pathways in tumour-associated macrophages

Tumour-associated macrophages (TAMs) are highly plastic and are broadly grouped into two major functional states, namely the pro-inflammatory M1-type and the pro-tumoural M2-type. Conversion of the functional states of TAMs is regulated by various cytokines, chemokines growth factors and other secreted factors in the microenvironment. Dysregulated metabolism is a hallmark of cancer. Emerging evidence suggests that metabolism governs the TAM differentiation and functional conversation in support of tumour growth and metastasis. Aside from the altered metabolism reprogramming in TAMs, extracellular metabolites secreted by cancer, stromal and/or other cells within the tumour microenvironment have been found to regulate TAMs through passive competition for metabolite availability and direct regulation via receptor/transporter-mediated signalling reaction. In this review, we focus on the regulatory roles of different metabolites and metabolic pathways in TAM conversion and function. We also discuss if the dysregulated metabolism in TAMs can be exploited for the development of new therapeutic strategies against cancer.

Post-diagnostic statin use and breast cancer-specific mortality: a population-based cohort study

PURPOSE

Statins are the most widely prescribed cholesterol lowering medications and have been associated with both improved and unchanged breast cancer outcomes in previous studies. This study examines the association between the post-diagnostic use of statins and breast cancer outcomes (death and recurrence) in a large, representative sample of New Zealand (NZ) women with breast cancer.

METHODS

Women diagnosed with a first primary breast cancer between 2007 and 2016 were identified from four population-based regional NZ breast cancer registries and linked to national pharmaceutical data, hospital discharges, and death records. Cox proportional hazard models were used to estimate the hazard of breast cancer-specific death (BCD) associated with any post-diagnostic statin use.

RESULTS

Of the 14,976 women included in analyses, 27% used a statin after diagnosis and the median follow up time was 4.51 years. Statin use (vs non-use) was associated with a statistically significant decreased risk of BCD (adjusted hazard ratio: 0.74; 0.63-0.86). The association was attenuated when considering a subgroup of 'new' statin users (HR: 0.91; 0.69-1.19), however other analyses revealed that the protective effect of statins was more pronounced in estrogen receptor positive patients (HR: 0.77; 0.63-0.94), postmenopausal women (HR: 0.74; 0.63-0.88), and in women with advanced stage disease (HR: 0.65; 0.49-0.84).

CONCLUSION

In this study, statin use was associated with a statistically significant decreased risk of breast cancer death, with subgroup analyses revealing a more protective effect in ER+ patients, postmenopausal women, and in women with advanced stage disease. Further research is warranted to determine if these associations are replicated in other clinical settings.

Assessment in vitro of interactions between anti-cancer drugs and noncancer drugs commonly used by cancer patients

Cancer patients often suffer from cancer symptoms, treatment complications and concomitant diseases and are, therefore, often treated with several drugs in addition to anticancer drugs. Whether such drugs, here denoted as 'concomitant drugs', have anticancer effects or interact at the tumor cell level with the anticancer drugs is not very well known. The cytotoxic effects of nine concomitant drugs and their interactions with five anti-cancer drugs commonly used for the treatment of colorectal cancer were screened over broad ranges of drug concentrations in vitro in the human colon cancer cell line HCT116wt. Seven additional tyrosine kinase inhibitors were included to further evaluate key findings as were primary cultures of tumor cells from patients with colorectal cancer. Cytotoxic effects were evaluated using the fluorometric microculture cytotoxicity assay (FMCA) and interaction analysis was based on Bliss independent interaction analysis. Simvastatin and loperamide, included here as an opioid agonists, were found to have cytotoxic effects on their own at reasonably low concentrations whereas betamethasone, enalapril, ibuprofen, metformin, metoclopramide, metoprolol and paracetamol were inactive also at very high concentrations. Drug interactions ranged from antagonistic to synergistic over the concentrations tested with a more homogenous pattern of synergy between simvastatin and protein kinase inhibitors in HCT116wt cells. Commonly used concomitant drugs are mostly neither expected to have anticancer effects nor to interact significantly with anticancer drugs frequently used for the treatment of colorectal cancer.

Comparison of changes in lipid profiles of premenopausal women with early-stage breast cancer treated with different endocrine therapies

Adjuvant endocrine therapy improves the prognosis of early breast cancer with hormone receptor positivity. However, there is no systematic report on the effect of endocrine therapy (particularly ovarian function suppression, OFS) on serum lipids in premenopausal women. This retrospective cohort study aimed to determine whether various endocrine treatments had different effects on blood lipids. This study enrolled 160 premenopausal patients with stage I-III breast cancer in eastern China. The initial diagnostic information was retrieved from patient's medical records, including age at the time of diagnosis, tumor characteristics, anticancer treatment and past medical history. The changes in blood lipids in patients receiving different types of endocrine therapy were compared at the 3rd, 6th, 12th, and 24th months after initiating endocrine therapy. Generalized linear mixed model was used in our analyses. Our data revealed that low-density lipoprotein cholesterol (LDL-C) levels in patients with tamoxifen (TAM) were significantly lower in the 6th, 12th, and 24th months than that in the 3rd month, while high-density lipoprotein cholesterol (HDL-C) levels in the 6th, 12th, and 24th months were significantly higher than that in the 3rd month, indicating that blood lipid levels generally improved with time. While in TAM plus OFS group, HDL-C levels were significantly higher in the 24th month than in the 3rd month, total cholesterol (TC) levels were significantly higher in the 24th month than in the 6th month. The lipid profiles of OFS plus aromatase inhibitor (AI) group did not show significant differences at any time point but were significantly higher than those of the other two groups especially in LDL and TC. TAM group tended to have lower serum lipid levels. With longer follow-up, no statistically significant difference in values was observed between TAM and TAM plus OFS groups at various time points. Compared with the other two groups, OFS plus AI group presented an increasing trend toward LDL-C and TC. The risk of dyslipidemia requires further investigation using a large sample size.

The effect of non-oncology drugs on clinical and genomic risk in early luminal breast cancer

BACKGROUND

An effect of non-oncology medications on cancer outcome has been proposed. In this study, we aimed to systematically examine the impact of commonly prescribed non-oncology drugs on clinical risk and on the genomic risk [based on the Oncotype DX recurrence score (RS)] in early breast cancer (BC).

EXPERIMENTAL DESIGN

We collected data on clinical risk (stage and grade), genomic risk (Oncotype DX RS), and on non-oncology medications administered to 1423 patients with estrogen receptor-positive human epidermal growth factor receptor 2-negative BC during the month of their surgery. The influence of various medications on clinical and genomic risks was evaluated by statistical analysis.

RESULTS

Out of the multiple drugs we examined, levothyroxine was significantly associated with a high Oncotype DX RS (mean 24.78; P < 0.0001) and metformin with a low Oncotype DX RS (mean 14.87; P < 0.01) compared with patients not receiving other non-oncology drugs (mean 18.7). By contrast, there were no differences in the clinical risk between patients receiving metformin, levothyroxine, or no other non-oncology drugs. Notably, there was no association between the consumption of levothyroxine and metformin and proliferation marker (Ki67) levels, but both drugs were significantly associated with progesterone-related features, suggesting that they influence genomic risk through estrogen-dependent signaling.

CONCLUSIONS

The results of this study indicate a significant impact of metformin and levothyroxine on clinical decisions in luminal BC, with potential impact on the clinical course of these patients.

Enhanced CHOLESTEROL biosynthesis promotes breast cancer metastasis via modulating CCDC25 expression and neutrophil extracellular traps formation

Neutrophil extracellular traps (NETs) has been demonstrated to regulate the metastasis of breast cancer. In this study, we showed that de novo cholesterol biosynthesis induced by ASPP2 depletion in mouse breast cancer cell 4T1 and human breast cancer cell MDA-MB-231 promoted NETs formation in vitro, as well as in lung metastases in mice intravenously injected with ASPP2-deficient 4T1 cells. Simvastatin and berberine (BBR), cholesterol synthesis inhibitors, efficiently blocked ASPP2-depletion induced NETs formation. Cholesterol biosynthesis greatly enhanced Coiled-coil domain containing protein 25 (CCDC25) expression on cancer cells as well as in lung metastases. CCDC25 expression was co-localized with caveolin-1, a lipid raft molecule, and was damped by inhibitor of lipid rafts formation. Our data suggest that cholesterol biosynthesis promotes CCDC25 expression in a lipid raft-dependent manner. Clinically, the expression of CCDC25 was positively correlated with the expression of 3-hydroxy-3-methylglutaryl-CoAreductase (HMRCG), and citrullinated histone H3 (H3cit), in tissues from breast cancer patients. High expression of CCDC25 and HMGCR was related with worse prognosis in breast cancer patients. In conclusion, our study explores a novel mechanism for de novo cholesterol biosynthesis in the regulation of CCDC25 expression, NETs formation and breast cancer metastasis. Targeting cholesterol biosynthesis may be promising therapeutic strategies to treat breast cancer metastasis.

The association between serum lipid levels and histological type of breast cancer

Background

Studies have investigated the association between serum lipids level or apolipoprotein levels and breast cancer (BC) risk. However, the relationship between serum lipids level and apolipoprotein levels and histological type of breast cancer remains unclear. This study was aimed to explore the association between serum lipids level and the histological type of BC, particularly to estrogen receptor (ER) and progesterone receptor (PR) positive BC.

Materials and methods

220 cases of pathology-confirmed BC were retrospectively collected in this study. Patients’ demographic information, clinical data, and pathological features were obtained from medical records. Serum levels including high-density lipoprotein-cholesterol (HDL-c), low-density lipoprotein-cholesterol (LDL-c), total cholesterol (TC), triglyceride (TG), apolipoprotein A (ApoA), ApoB, ApoE and lipoprotein a(LP(a)) were collected before treatment. Logistic regression analyses were used to show the association between serum lipids and subtypes of BC. Receiver operating characteristic (ROC) curves were generated to analyze the predictive performance.

Results

There were 70 ER-negative and 73 PR-negative BC. Patients with ER-negative BC had higher HDL-c, higher LDL-c, and higher LP(a) than those in ER-positive one (p < 0.05). Patients with PR-negative BC were more likely to have high LDL-c and high LP(a) levels than patients with PR-positive one (p < 0.05). Multivariate logistic regression analysis showed that serum HDL-c (odds ratio (OR): 0.27, 95% confidence interval (CI) 0.10–0.76), LDL-c (OR: 0.19, 95%CI 0.04–0.93) and LP(a) (OR: 0.23,95%CI 0.07–0.80) levels were negatively associated with ER-positive BC, and serum HDL-c and LDL-c levels were significantly negatively associated with PR-positive BC (OR: 0.32, 95%CI 0.12–0.82; OR: 0.14, 95%CI 0.03–0.77). In addition, ER and PR positive BC was negatively associated with serum HDL-c and LDL-c levels (OR = 0.39, 95% CI 0.17–0.91; OR = 0.22, 95% CI 0.06–0.85) after adjusting with confounders. Serum HDL-c level (OR = 0.13, 95% CI 0.02–0.87) was still independently associated with ER and PR positive BC in postmenopausal women. The area under the curves (AUCs) of HDL-c to identify ER-positive BC, PR-positive BC, and ER and PR positive BC were 0.65 (95%CI 0.58–0.73, P < 0.01), 0.62 (95%CI 0.54–0.69, P < 0.01) and 0.64 (95%CI 0.56–0.72, P < 0.01), respectively.

Conclusions

Serum HDL-c and LDL-c levels were related to ER or PR positive BC. Lipid levels may also have acceptable performance in identifying BC histological type.

Ezetimibe and Cancer: Is There a Connection?

The high level of serum cholesterol caused by the excessive absorption of cholesterol can lead to hypercholesteremia, thus promoting the occurrence and development of cancer. Ezetimibe is a drug that reduces cholesterol absorption and has been widely used for the treatment of patients with high circulating cholesterol levels for many years. Mechanistically, ezetimibe works by binding to NPC1L1, which is a key mediator of cholesterol absorption. Accumulating data from preclinical models have shown that ezetimibe alone could inhibit the development and progression of cancer through a variety of mechanisms, including anti-angiogenesis, stem cell suppression, anti-inflammation, immune enhancement and anti-proliferation. In the past decade, there has been heated discussion on whether ezetimibe combined with statins will increase the risk of cancer. At present, more and more evidence shows that ezetimibe does not increase the risk of cancers, which supports the role of ezetimibe in anti-cancer. In this review, we discussed the latest progress in the anti-cancer properties of ezetimibe and elucidated its underlying molecular mechanisms. Finally, we highlighted the potential of ezetimibe as a therapeutic agent in future cancer treatment and prevention.

Statins inhibit proliferation and induce apoptosis in triple-negative breast cancer cells

TP53 (p53) is mutated in 80–90% of cases of triple-negative breast cancer (TNBC). Statins, which are widely used to treat elevated cholesterol, have recently been shown to degrade mutant p53 protein and exhibit anti-cancer activity. The aim of this work was to evaluate the potential of statins in the treatment of TNBC. The anti-proliferative effects of 2 widely used statins were investigated on a panel of 15 cell lines representing the different molecular subtypes of breast cancer. Significantly lower IC50 values were found in triple-negative (TN) than in non-TN cell lines (atorvastatin, p < 0.01; simvastatin p < 0.05) indicating greater sensitivity. Furthermore, cell lines containing mutant p53 were more responsive to both statins than cell lines expressing wild-type p53, suggesting that the mutational status of p53 is a potential predictive biomarker for statin response. In addition to inhibiting proliferation, simvastatin was also found to promote cell cycle arrest and induce apoptosis. Using an apoptosis array capable of detecting 43 apoptosis-associated proteins, a novel protein shown to be upregulated by simvastatin was the IGF-signalling modulator, IGBP4, a finding we confirmed by Western blotting. Finally, we found synergistic growth inhibition between simvastatin and the IGF-1R inhibitor, OSI-906 as well as between simvastatin and doxorubicin or docetaxel. Our work suggests repurposing of statins for clinical trials in patients with TNBC. Based on our findings, we suggest that these trials investigate statins in combination with either doxorubicin or docetaxel and include p53 mutational status as a potential predictive biomarker.

Lipid Metabolism and Cancer

Lipid metabolism is involved in the regulation of numerous cellular processes, such as cell growth, proliferation, differentiation, survival, apoptosis, inflammation, movement, membrane homeostasis, chemotherapy response, and drug resistance. Reprogramming of lipid metabolism is a typical feature of malignant tumors. In a variety of cancers, fat uptake, storage and fat production are up-regulated, which in turn promotes the rapid growth, invasion, and migration of tumors. This paper systematically summarizes the key signal transduction pathways and molecules of lipid metabolism regulating tumors, and the role of lipid metabolism in programmed cell death. In conclusion, understanding the potential molecular mechanism of lipid metabolism and the functions of different lipid molecules may facilitate elucidating the mechanisms underlying the occurrence of cancer in order to discover new potential targets for the development of effective antitumor drugs.

The Impact of Statin Use and Breast Cancer Recurrence - A Retrospective Study in Singapore

Introduction

Statins, HMG-CoA reductase inhibitors, are commonly used cholesterol-lowering medications which are also increasingly recognized to have anti-cancer properties for various cancers, including breast cancer. Most clinical evidence supports a protective effect of statin on reducing breast cancer recurrence, particularly in hormone-receptor positive breast cancers.This study seeks to study the impact of statin use on breast cancer recurrence in an Asian population.

Methods

This is a retrospective study of patients diagnosed with breast cancer at the National Cancer Centre and Singapore General Hospital from 2005-2015. Statin use was defined as use after surgery. Associations between statin use, breast cancer recurrence and overall survival were estimated using Cox proportional hazards regression with adjustment for age, TNM stage, grade, ER/HER2 status, and co-morbidities. Associations between statin-use and disease-specific survival were estimated using competing risks regression.

Results

A total of 7858 females with breast cancer were studied, 1353(17.2%) were statin users, 6505(82.8%) were non-statin users, with a median follow-up of 8.67 years. Distribution of cancer stage, histology, molecular subtypes and grades were similar in both groups. Estrogen receptor(ER) positive (HR 0.57,95%CI 0.43-0.76,p<0.001) and HER2 negative (HR 0.74,95%CI 0.57-0.96,p=0.026) invasive cancers had a lower risk of recurrence in statin users. Statin users trended towards a long term recurrence-risk reduction (all subtypes,HR 0.48,p=0.002; ER-, HR 0.34,p=0.036; HER2+,HR 0.10,p=0.002). The risk-reduction benefit is not appreciated in statin users with DCIS, possibly due to small recurrence event numbers. Disease-specific survival benefit was seen in statin users with ER+ cancers (adjusted SHR 0.71,95%CI 0.53-0.96,p=0.027), especially ER+ invasive cancers (adjusted SHR 0.72, 95%CI 0.53-0.97,p=0.028), but with no statistically significant benefit in overall survival for statin users (all subtypes).

Conclusion

This is the first known retrospective study on the effect of statin use and breast cancer recurrence in an Asian population. Similar to previous international studies, statin use is associated with a risk reduction in breast cancer recurrence. This is especially beneficial in patients who have ER+ and HER2- invasive breast cancer. Statin use is also associated with a reduced risk of breast cancer recurrence in all subtypes of breast cancer in the long term (>6 years post diagnosis).

Stimulated Raman scattering microscopy with spectral phasor analysis: applications in assessing drug-cell interactions

Statins have displayed significant, although heterogeneous, anti-tumour activity in breast cancer disease progression and recurrence. They offer promise as a class of drugs, normally used for cardiovascular disease control, that could have a significant impact on the treatment of cancer. Understanding their mode of action and accurately assessing their efficacy on live cancer cells is an important and significant challenge. Stimulated Raman scattering (SRS) microscopy is a powerful, label-free imaging technique that can rapidly characterise the biochemical responses of live cell populations following drug treatment. Here, we demonstrate multi-wavelength SRS imaging together with spectral phasor analysis to characterise a panel of breast cancer cell lines (MCF-7, SK-BR-3 and MDA-MB-231 cells) treated with two clinically relevant statins, atorvastatin and rosuvastatin. Label-free SRS imaging within the high wavenumber region of the Raman spectrum (2800–3050 cm⁻¹) revealed the lipid droplet distribution throughout populations of live breast cancer cells using biocompatible imaging conditions. A spectral phasor analysis of the hyperspectral dataset enables rapid differentiation of discrete cellular compartments based on their intrinsic SRS characteristics. Applying the spectral phasor method to studying statin treated cells identified a lipid accumulating phenotype in cell populations which displayed the lowest sensitivity to statin treatment, whilst a weaker lipid accumulating phenotype was associated with a potent reduction in cell viability. This study provides an insight into potential resistance mechanisms of specific cancer cells towards treatment with statins. Label-free SRS imaging provides a novel and innovative technique for phenotypic assessment of drug-induced effects across different cellular populations and enables effective analysis of drug–cell interactions at the subcellular scale.

Stimulated Raman scattering microscopy with spectral phasor analysis provides a label-free approach for phenotypic evaluation of drug-induced effects.

Copy number amplification of ENSA promotes the progression of triple-negative breast cancer via cholesterol biosynthesis

Copy number alterations (CNAs) are pivotal genetic events in triple-negative breast cancer (TNBC). Here, our integrated copy number and transcriptome analysis of 302 TNBC patients reveals that gene alpha-endosulfine (ENSA) exhibits recurrent amplification at the 1q21.3 region and is highly expressed in TNBC. ENSA promotes tumor growth and indicates poor patient survival in TNBC. Mechanistically, we identify ENSA as an essential regulator of cholesterol biosynthesis in TNBC that upregulates the expression of sterol regulatory element-binding transcription factor 2 (SREBP2), a pivotal transcription factor in cholesterol biosynthesis. We confirm that ENSA can increase the level of p-STAT3 (Tyr705) and activated STAT3 binds to the promoter of SREBP2 to promote its transcription. Furthermore, we reveal the efficacy of STAT3 inhibitor Stattic in TNBC with high ENSA expression. In conclusion, the amplification of ENSA at the 1q21.3 region promotes TNBC progression and indicates sensitivity to STAT3 inhibitors.

Copy number alterations are pivotal genetic events in triple-negative breast cancer. Here the authors show the amplification of ENSA at the 1q21.3 region promotes the progression of TNBC via up-regulation of cholesterol biosynthesis.

Statin use and patterns of breast cancer recurrence in the Malmö Diet and Cancer Study

BACKGROUND

Accumulating evidence suggests that statins have a beneficial effect on breast cancer prognosis. Previous studies have reported a positive association between statin use and breast cancer survival; however, the relationship between statin use and patterns of breast cancer recurrence remains unclear.

PATIENTS AND METHODS

We identified all Malmö Diet and Cancer Study (MDCS) participants diagnosed with incident invasive breast cancer between 2005 and 2014. The follow-up period began at breast cancer diagnosis and continued until the first invasive breast cancer recurrence event, death, emigration or the end of the follow-up (June 8, 2020). We estimated incidence rates (IRs) of recurrence and fit Cox regression models to compute crude and adjusted hazard ratios (HRs) with 95% confidence intervals (95% CIs) for disease recurrence to compare post-diagnosis statin users with non-users.

RESULTS

The final study cohort consisted of 360 eligible patients with a median follow-up of 8.6 years. Overall, there were 71 recurrences in 2932 total person-years. According to statin use, there were 14 recurrences in 595 person-years among statin users, and 57 recurrences in 2337 person-years in non-users. Statin use was associated with a reduced risk of breast cancer recurrence (HR_adj = 0.88 [95% CI: 0.82-0.96]). Regarding the pattern of recurrence, statin use was associated with a reduced risk of distant recurrence (HR_adj = 0.86 [95% CI: 0.80-0.94]) but not loco-regional recurrence (HR_adj = 0.97 [95% CI: 0.87-1.08]).

CONCLUSION

In the MDCS, statin use was associated with a reduced risk of distant breast cancer recurrence, whereas no association between statin use and loco-regional breast cancer recurrence was found. This site-based difference in disease recurrence may be explained by statin's inhibition of epithelial-mesenchymal transition.

Comparison of adverse drug reactions between tamoxifen and toremifene in breast cancer patients with different CYP2D6 genotypes: a propensity-score matched cohort study

CYP2D6 gene polymorphism had a profound impact upon the effect of tamoxifen as adjuvant endocrine therapy in breast cancers. However, it had never been reported whether the adverse drug reactions vary by CYP2D6 metabolic status for patients treated with tamoxifen or toremifene. We conducted an retrospective study in breast cancer patients to investigate the impact of CYP2D6 metabolizers on liver dysfunction events, gynecological events, and dyslipidemia events. According to CYP2D6*10 (100C → T) genotype, the enrolled patients were further categorized into four cohorts (extensive metabolizers taking tamoxifen [EM + TAM], extensive metabolizers taking toremifene [EM + TOR], intermediate metabolizers taking tamoxifen [IM + TAM], intermediate metabolizers taking toremifene cohort [IM + TOR]). A total of 192 patients were included into the study, with a median follow-up time of 26.2 months. In EM + TAM cohort, the risks of liver dysfunction events (P = 0.004) and gynecological events (P = 0.004) were significantly higher compared with EM + TOR cohort. In IM + TAM cohort, the risks of liver dysfunction events (P = 0.14) and gynecological events (P = 0.99) were not significantly different from IM + TOR cohort. Significant decrease of total cholesterol was observed in EM + TAM cohort around 1 year after taking tamoxifen (P < 0.001). Significant interactions between CYP2D6 metabolic status and endocrine agents were observed in terms of liver dysfunction events (p-interaction = 0.007) and gynecological events (p-interaction = 0.026). These findings suggested that CYP2D6 gene polymorphism played a significant role in predicting liver dysfunction, gynecological diseases and lipid metabolism changes among patients taking tamoxifen or toremifene. This article is protected by copyright. All rights reserved.

Association of statin use with clinical outcomes in patients with triple-negative breast cancer

BACKGROUND

Previous studies have examined the association of statin therapy and breast cancer outcomes with mixed results. The objective of this study was to investigate the clinical effects of incident statin use among individuals with triple-negative breast cancer (TNBC).

METHODS

Data from the Surveillance, Epidemiology, and End Results-Medicare and Texas Cancer Registry-Medicare databases were used, and women aged ≥66 years who had stage I, II, and III breast cancer were identified. Multivariable Cox proportional hazards regression models were used to examine the association of new statin use in the 12 months after a breast cancer diagnosis with overall survival (OS) and breast cancer-specific survival (BCSS).

RESULTS

When examining incident statin use, defined as the initiation of statin therapy in the 12 months after breast cancer diagnosis, a significant association was observed between statin use and improved BCSS (standardized hazard ratio, 0.42; 95% confidence interval [CI], 0.20-0.88; P = .022) and OS (hazard ratio, 0.70; 95% CI, 0.50-0.99; P = .046) among patients with TNBC (n = 1534). No association was observed with BCSS (standardized hazard ratio, 0.99; 95% CI, 0.71-1.39; P = .97) or OS (hazard ratio, 1.04; 95% CI, 0.92-1.17; P = .55) among those without TNBC (n = 15,979). The results were consistent when examining statin exposure as a time-varying variable.

CONCLUSIONS

Among women with I, II, and III TNBC, initiation of statin therapy in the 12 months after breast cancer diagnosis was associated with an OS and BCSS benefit. Statins may have a role in select patients with breast cancer, and further investigation is warranted.

Cholesterol lowering drug use and breast cancer survival: the Multiethnic Cohort Study

PURPOSE

Prior studies conducted primarily in white populations have suggested that pre-diagnostic cholesterol lowering drugs (CLDs) improved survival among women with breast cancer (BC). However, this association had not been well characterized in diverse racial/ethnic populations. We investigated whether pre-diagnostic CLD use is associated with all-cause and BC-specific mortality among female BC cases of the Multiethnic Cohort (MEC).

METHODS

CLD use was ascertained through questionnaires administered in 2003-2008. A total of 1448 incident BC cases were identified by linkage to SEER cancer registries in Hawaii and California from 2003 to 2014. Multivariable Cox regression was conducted to estimate hazard ratios (HR) and 95% confidence intervals (CI) of the associations of pre-diagnostic CLD use with all-cause and BC-specific mortality, adjusting for tumor characteristics, first course of treatment, health behaviors, co-morbidities, and demographics. Subgroup analyses by stage and hormone receptor status were conducted for all-cause mortality.

RESULTS

There were 224 all-cause and 87 BC-specific deaths among the 1448 BC cases during a median follow-up of 4.5 years after diagnosis. Women with BC who ever used CLDs had a 27% lower hazard of all-cause mortality (HR 0.73, 95% CI 0.54-0.98) and 17% lower hazard of BC-specific mortality (HR 0.83, 95% CI 0.49-1.39) compared to never users. CLD use reduced mortality among women with advanced-stage tumors and hormone receptor-positive breast tumors (HR 0.54 95% CI 0.33-0.90; HR 0.69, 95% CI 0.48-0.99, respectively).

CONCLUSION

These findings demonstrate an improved survival associated with CLD use prior to diagnosis in a multiethnic population of women with BC.

High CYP27A1 expression is a biomarker of favorable prognosis in premenopausal patients with estrogen receptor positive primary breast cancer

27-hydroxycholesterol (27HC), synthesized from cholesterol by the enzyme CYP27A1, differentially impacts estrogen receptor positive (ER+) breast cancer (BC) cell growth depending on estrogen levels. This study examined the association between CYP27A1 expression and prognosis in a cohort of 193 premenopausal patients with lymph node-negative primary BC with limited exposure to adjuvant systemic cancer treatments. In multivariable analyses among patients with ER+ tumors, high CYP27A1 protein and mRNA expressions were associated with four- and eight-fold reductions in the incidence of distant recurrence-free survival events: HR_adj = 0.26, 95% CI = 0.07-0.93 and HR_adj = 0.13, 95% CI = 0.03-0.60, respectively. In vitro studies revealed that 27HC treatment potently inhibited ER+ BC cell proliferation under lipid-depleted conditions regardless of estradiol levels, transcriptionally mediated through the downregulation of ER signaling with a concomitant upregulation of cholesterol export. Importantly, if validated, these results may have implications for adjuvant treatment decisions in premenopausal patients, especially when de-escalation of therapy is being considered.

Sanhuang Decoction Controls Tumor Microenvironment by Ameliorating Chronic Stress in Breast Cancer: A Report of Ninety Cases

Long-term endocrine treatment which results in estrogen deprivation causes chronic stress associated with a series of uncomfortable symptoms leading not only to a decrease in quality of life but also to cancer recurrence, which may be mediated primarily through the enhanced expression of angiogenic factors, as well as a series of inflammatory microenvironmental changes that favor tumor progression. In this study, we designed a clinical trial and aimed to explore the effects of Sanhuang Decoction (SHD) treatment on chronic stress, inflammatory factors, and breast cancer recovery. A total of 90 patients with breast cancer who met the inclusion/exclusion criteria were randomly allocated to a treatment or control group. The treatment group received the standard endocrine treatment and the traditional Chinese medicine decoction known as SHD. The control group received the standard endocrine treatment only. The treatment period was 6 months. The modified Kupperman Menopausal Index, the self-rating anxiety scale, and the self-rating depression scale were evaluated once per month. The body microenvironment plasma indices related to chronic stress, such as oxidative and antioxidative stress markers, inflammatory factors, hemorheology, coagulation, lipid and D-dimer, immunologic functions, tumor biomarkers, and angiogenic factors of the vascular endothelial growth factor (VEGF) were measured before and after 6 months of treatment. After treatment for 5 months, the scores in the treatment group decreased to nearly normal levels and the control group showed no significant improvement. After treatment for 6 months, all indices related to the body microenvironment, as well as the tumor biomarkers and carcinoembryonic antigen, carbohydrate antigen 153, and angiogenic factor VEGF levels improved significantly to normal levels in the treatment group. Our primary research showed that treatment with SHD effectively improved the quality of life of breast cancer patients by facilitating a change in the body microenvironment that controlled tumor growth and prevented drug resistance.

Dysregulated cholesterol homeostasis results in resistance to ferroptosis increasing tumorigenicity and metastasis in cancer

Hypercholesterolemia and dyslipidemia are associated with an increased risk for many cancer types and with poor outcomes in patients with established disease. Whereas the mechanisms by which this occurs are multifactorial we determine that chronic exposure of cells to 27-hydroxycholesterol (27HC), an abundant circulating cholesterol metabolite, selects for cells that exhibit increased cellular uptake and/or lipid biosynthesis. These cells exhibit substantially increased tumorigenic and metastatic capacity. Notably, the metabolic stress imposed upon cells by the accumulated lipids requires sustained expression of GPX4, a negative regulator of ferroptotic cell death. We show that resistance to ferroptosis is a feature of metastatic cells and further demonstrate that GPX4 knockdown attenuates the enhanced tumorigenic and metastatic activity of 27HC resistant cells. These findings highlight the general importance of ferroptosis in tumor growth and metastasis and suggest that dyslipidemia/hypercholesterolemia impacts cancer pathogenesis by selecting for cells that are resistant to ferroptotic cell death.

Effects of Tamoxifen vs. Toremifene on fatty liver development and lipid profiles in breast Cancer

BACKGROUND

Tamoxifen (TAM) and Toremifene (TOR), two kinds of selective estrogen receptor modulators (SERMs), have equal efficacy in breast cancer patients. However, TAM has been proved to affect serum lipid profiles and cause fatty liver disease. The study aimed to compare the effects of TAM and TOR on fatty liver development and lipid profiles.

METHODS

This study performed a retrospective analysis of 308 SERMs-treated early breast cancer patients who were matched 1:1 based on propensity scores. The follow-up period was 3 years. The primary outcomes were fatty liver detected by ultrasonography or computed tomography (CT), variation in fibrosis indexes, and serum lipid profiles change.

RESULTS

The cumulative incidence rate of new-onset fatty liver was higher in the TAM group than in the TOR group (113.2 vs. 67.2 per 1000 person-years, p < 0.001), and more severe fatty livers occurred in the TAM group (25.5 vs. 7.5 per 1000 person-years, p = 0.003). According to the Kaplan-Meier curves, TAM significantly increased the risk of new-onset fatty liver (25.97% vs. 17.53%, p = 0.0243) and the severe fatty liver (5.84% vs. 1.95%, p = 0.0429). TOR decreased the risk of new-onset fatty liver by 45% (hazard ratio = 0.55, p = 0.020) and showed lower fibrotic burden, independent of obesity, lipid, and liver enzyme levels. TOR increased triglycerides less than TAM, and TOR increased high-density lipoprotein cholesterol, while TAM did the opposite. No significant differences in total cholesterol and low-density lipoprotein cholesterol are observed between the two groups.

CONCLUSIONS

TAM treatment is significantly associated with more severe fatty liver disease and liver fibrosis, while TOR is associated with an overall improvement in lipid profiles, which supports continuous monitoring of liver imaging and serum lipid levels during SERM treatment.

Derivation and validation of a lipid-covered prognostic model for mature T-cell lymphomas

Background

Mature T-cell lymphomas (MTCLs), a group of diseases with high aggressiveness and vulnerable prognosis, lack for the accurate prognostic stratification systems at present. Novel prognostic markers and models are urgently demanded. Aberrant lipid metabolism is closely related to the tumor progression but its prognostic significance in MTCLs remains unexplored. This study aims to investigate the relationship between dysregulated lipid metabolism and survival prognosis of MTCLs and establish a novel and well-performed prognostic scoring system for MTCL patients.

Methods

A total of 173 treatment-naive patients were enrolled in this study. Univariate and multivariate Cox regression analysis were performed to assess the prognostic significance of serum lipid profiles and screen out independent prognostic factors, which constituted a novel prognostic model for MTCLs. The performance of the novel model was assessed in the training and validation cohort, respectively, by examining its calibration, discrimination and clinical utility.

Results

Among the 173 included patients, 115 patients (01/2006–12/2016) constituted the training cohort and 58 patients (01/2017–06/2020) formed the validation cohort. Univariate analysis revealed declined total cholesterol (TC, P = 0.000), high-density lipoprotein cholesterol (HDL-C, P = 0.000) and increased triglycerides (TG, P = 0.000) correlated to inferior survival outcomes. Multivariate analysis revealed extranodal involved sites ≥ 2 (hazard ratio [HR]: 2.439; P = 0.036), β2-MG ≥ 3 mg/L (HR: 4.165; P = 0.003) and TC < 3.58 mmol/L (HR: 3.338; P = 0.000) were independent predictors. Subsequently, a novel prognostic model, EnBC score, was constructed with these three factors. Harrell’s C-index of the model in the training and validation cohort was 0.840 (95% CI 0.810–0.870) and 0.882 (95% CI 0.822–0.942), respectively, with well-fitted calibration curves. The model divided patients into four risk groups with distinct OS [median OS: not available (NA) vs. NA vs. 14.0 vs. 4.0 months, P < 0.0001] and PFS (median PFS: 84.0 vs. 19.0 vs. 8.0 vs. 1.5 months, P < 0.0001). Time-dependent receiver operating characteristic curve and decision curve analysis  further revealed that EnBC score provided higher diagnostic capacity and clinical benefit, compared with International Prognostic Index (IPI).

Conclusion

Firstly, abnormal serum lipid metabolism was demonstrated significantly related to the survival of MTCL patients. Furthermore, a lipid-covered prognostic scoring system was established and performed well in stratifying patients with MTCLs.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12935-021-02042-3.

Cholesterol-Induced Metabolic Reprogramming in Breast Cancer Cells Is Mediated via the ERRα Pathway

Simple Summary

There is increasing evidence that obesity and high circulating cholesterol levels are associated with an increased risk of recurrence and a higher mortality rate in breast cancer patients via altering the metabolic programming in breast cancer cells. However, the underlying molecular mechanism by which high cholesterol levels reprogram the metabolic pathways in breast cancer cells is not well-understood. We have previously demonstrated that cholesterol acts as an endogenous agonist of estrogen-related receptor α (ERRα), a strong regulator of cellular metabolism. The aim of the current study is to demonstrate whether cholesterol/obesity mediates its pathogenic effect in breast cancer cells via altering metabolic pathways in an ERRα-dependent manner. The findings of this study provide mechanistic insights into the link between cholesterol/obesity and metabolic reprogramming in breast cancer patients and reveal the metabolic vulnerabilities in such breast cancer patients that could be therapeutically targeted.

Abstract

The molecular mechanism underlying the metabolic reprogramming associated with obesity and high blood cholesterol levels is poorly understood. We previously reported that cholesterol is an endogenous ligand of the estrogen-related receptor alpha (ERRα). Using functional assays, metabolomics, and genomics, here we show that exogenous cholesterol alters the metabolic pathways in estrogen receptor-positive (ER+) and triple-negative breast cancer (TNBC) cells, and that this involves increased oxidative phosphorylation (OXPHOS) and TCA cycle intermediate levels. In addition, cholesterol augments aerobic glycolysis in TNBC cells although it remains unaltered in ER+ cells. Interestingly, cholesterol does not alter the metabolite levels of glutaminolysis, one-carbon metabolism, or the pentose phosphate pathway, but increases the NADPH levels and cellular proliferation, in both cell types. Importantly, we show that the above cholesterol-induced modulations of the metabolic pathways in breast cancer cells are mediated via ERRα. Furthermore, analysis of the ERRα metabolic gene signature of basal-like breast tumours of overweight/obese versus lean patients, using the GEO database, shows that obesity may modulate ERRα gene signature in a manner consistent with our in vitro findings with exogenous cholesterol. Given the close link between high cholesterol levels and obesity, our findings provide a mechanistic explanation for the association between cholesterol/obesity and metabolic reprogramming in breast cancer patients.

Identification of a Positive Association between Mammary Adipose Cholesterol Content and Indicators of Breast Cancer Aggressiveness in a French Population

BACKGROUND

Several studies have recently highlighted important roles for adipose tissue in cancer. However, few have examined adipose tissue cholesterol, and no study has been performed in breast adipose tissue associated with breast tumors.

OBJECTIVES

The present work was designed to determine if breast adipose tissue cholesterol from the tumor-surrounding area is associated with breast cancer aggressiveness.

METHODS

Between 2009 and 2011, 215 breast adipose tissue samples were collected at the Tours University Hospital (France) during surgery of women (aged 28-89 y) with invasive breast cancer. Associations of free cholesterol (FC), esterified cholesterol (EC), and total cholesterol (TC) amounts with clinical variables (age, BMI, and treated or untreated hypercholesterolemia) and tumor aggressiveness parameters [phenotype, grade, presence of inflammatory breast cancer (IBC), and multifocality] were tested using Student's t test and after ANOVA.

RESULTS

The predominant form of cholesterol in adipose tissue was FC, and 50% of patients had no detectable EC. The adipose tissue FC content (μg/mg total lipid) was 18% greater in patients >70 y old than in those 40-49 y old (P < 0.05) and the TC content tended to be 12% greater in untreated hypercholesterolemic patients than in normocholesterolemic patients (P = 0.06). Breast adipose cholesterol concentrations were increased in tissues obtained from patients with human-epidermal-growth-factor-receptor-2 (HER2) phenotype (+13% FC; P < 0.05 compared with luminal A), IBC (+15% FC; P = 0.06 compared with noninflammatory tumors), as well as with multifocal triple-negative tumors (+34% FC, P < 0.05; +30% TC, P < 0.05, compared with unifocal triple-negative tumors). Among patients with triple-negative tumors, hypercholesterolemia was significantly more common (P < 0.05) in patients with multifocal tumors (64%) than in patients with unifocal tumors (25%).

CONCLUSIONS

This study is the first of this magnitude that analyzes cholesterol concentrations in adipose tissue from female breast cancer patients. An increase in breast adipose tissue cholesterol content may contribute to breast cancer aggressiveness (HER2 phenotype, multifocality of triple-negative tumors, and IBC).

The relationship between post-diagnostic statin usage and breast cancer prognosis varies by hormone receptor phenotype: a systemic review and meta-analysis

BACKGROUND

Preclinical studies and epidemiologic data had indicated statins had antineoplastic properties in breast cancer patients. Since breast cancer treatment is based on its phenotype, it is important to explore influence of post-diagnosis statin usage on breast cancer patients with different phenotypes.

METHODS

We searched the related studies between inception and August, 2019 from MEDLINE and EMBASE. A total of 7 studies with 24,541 patients were identified. Stata/SE 15.0 and Review Manager 5.3 were used to analyze data. Inconsistency index was used to estimate heterogeneity. Begg's and Egger's regression test was used to examine publication bias.

RESULTS

Overall post-diagnostic statin use was associated with improved recurrence free survival (recurrence free survival (RFS); hazard ratio (HR) 0.74; 95% confidential interval (95% CI) 0.57-0.98), overall survival (overall survival (OS); HR 0.53; 95% CI 0.31-0.91) and cancer-specific survival (cancer-specific survival (CSS); and HR 0.61; 95% CI 0.41-0.91). In hormone receptor positive patients, statin use was associated with improved CSS (HR 0.74, 95% CI 0.65-0.84). No protective effect was found in either OS or RFS. In hormone receptor negative patients, statin was associated with reduced OS (HR 2.19, 95% CI 1.34-3.59) and reduced RFS, but without statistical significance.

CONCLUSIONS

Post-diagnostic statin use was associated with improved RFS, OS and CSS in breast cancer patients. Subgroup analysis indicted that the benefits of statin usage varied from hormone receptor phenotype type. Prospective randomized trial with patients of different hormone receptor types might be needed to help identify which subtype of breast cancer patients would benefit from post-diagnostic statin usage.

NSDHL promotes triple-negative breast cancer metastasis through the TGFβ signaling pathway and cholesterol biosynthesis

PURPOSE

Metastasis is the main cause of breast cancer mortality. Recent studies have proved that lipid metabolic reprogramming plays critical roles in breast cancer carcinogenesis and metastasis. We aim to identify critical lipid metabolism genes in breast cancer metastasis.

METHODS

We designed and cloned a CRISPR pooled library containing lipid metabolic gene guide RNAs and performed a genetic screen in vivo. Transwell assay and animal experiments were used to evaluate cell metastatic ability in vitro or in vivo, respectively. We performed immunohistochemistry with breast cancer tissue microarray to study the clinical significance of NSDHL.

FINDINGS

We identified a cholesterol metabolic enzyme, NSDHL, as a potential metastatic driver in triple-negative breast cancer. NSDHL was highly expressed in breast cancer tissues and predicted a poor prognosis. NSDHL knockdown significantly suppressed cell proliferation and migration. Mechanistically, NSDHL activated the TGFβ signaling pathway by inhibiting the endosomal degradation of TGFβR2. In addition, blocking the upstream metabolism of NSDHL with ketoconazole rescued cancer metastasis and TGFβR2 degradation. However, the inactivation of NSDHL (Y151X) did not rescue the migration ability and the TGFβR2 protein expression.

CONCLUSION

Taken together, our findings established that NSDHL serves as a metastatic driver, and its function depends on its enzyme activity in cholesterol biosynthesis and is mediated by the NSDHL-TGFβR2 signal pathway. Our study indicated that NSDHL and steroid biosynthesis may serve as new drug targets for patients with advanced breast cancer.

Metabolic Syndrome and Breast Cancer: Prevalence, Treatment Response, and Prognosis

Metabolic syndrome is a type of multifactorial metabolic disease with the presence of at least three factors: obesity, diabetes mellitus, low high-density lipoprotein, hypertriglyceridemia, and hypertension. Recent studies have shown that metabolic syndrome and its related components exert a significant impact on the initiation, progression, treatment response, and prognosis of breast cancer. Metabolic abnormalities not only increase the disease risk and aggravate tumor progression but also lead to unfavorable treatment responses and more treatment side effects. Moreover, biochemical reactions caused by the imbalance of these metabolic components affect both the host general state and organ-specific tumor microenvironment, resulting in increased rates of recurrence and mortality. Therefore, this review discusses the recent advances in the association of metabolic syndrome and breast cancer, providing potential novel therapeutic targets and intervention strategies to improve breast cancer outcome.

Influence of cholesterol on cancer progression and therapy

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Abnormality in blood cholesterol level is significantly correlated with risk of different cancers.

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Majority of tumor tissue from cancer patient exhibits overexpression of LDLR and ACAT for supporting rapid cancer cell proliferation.

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Alteration of the cholesterol metabolism in cancer cells hampers therapeutic response.

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Targeting cholesterol metabolism for treatment of cancer with other conventional chemotherapeutic drugs appears to be beneficial.

Cholesterol is a fundamental molecule necessary for the maintenance of cell structure and is vital to various normal biological functions. It is a key factor in lifestyle-related diseases including obesity, diabetes, cardiovascular disease, and cancer. Owing to its altered serum chemistry status under pathological states, it is now being investigated to unravel the mechanism by which it triggers various health complications. Numerous clinical studies in cancer patients indicate an alteration in blood cholesterol level (either decreased or increased) in comparison to normal healthy individuals. This article elaborates on our understanding as to how cholesterol is being hijacked in the malignancy for the development, survival, stemness, progression, and metastasis of cancerous cells. Also, it provides a glimpse of how cholesterol derived entities, alters the signaling pathway towards their advantage. Moreover, deregulation of the cholesterol metabolism pathway has been often reported to hamper various treatment strategies in different cancer. In this context, attempts have been made to bring forth its relevance in being targeted, in pre-clinical and clinical studies for various treatment modalities. Thus, understanding the role of cholesterol and deciphering associated molecular mechanisms in cancer progression and therapy are of relevance towards improvement in the management of various cancers.

Statins as Potential Chemoprevention or Therapeutic Agents in Cancer: a Model for Evaluating Repurposed Drugs

PURPOSE OF REVIEW

Repurposing established medicines for a new therapeutic indication potentially has important global and societal impact. The high costs and slow pace of new drug development have increased interest in more cost-effective repurposed drugs, particularly in the cancer arena. The conventional drug development pathway and evidence framework are not designed for drug repurposing and there is currently no consensus on establishing the evidence base before embarking on a large, resource intensive, potential practice changing phase III randomised controlled trial (RCT). Numerous observational studies have suggested a potential role for statins as a repurposed drug for cancer chemoprevention and therapy, and we review the strength of the cumulative evidence here.

RECENT FINDINGS

In the setting of cancer, a potential repurposed drug, like statins, typically goes through a cyclical history, with initial use for several years in another disease setting, prior to epidemiological research identifying a possible chemo-protective effect. However, further information is required, including review of RCT data in the initial disease setting with exploration of cancer outcomes. Additionally, more contemporary methods should be considered, such as Mendelian randomization and pharmaco-epidemiological research with "target" trial design emulation using electronic health records. Pre-clinical and traditional observational data potentially support the role of statins in the treatment of cancer; however, randomised trial evidence is not supportive. Evaluation of contemporary methods provides little added support for the use of statin therapy in cancer. We provide complementary evidence of alternative study designs to enable a robust critical appraisal from a number of sources of the go/no-go decision for a prospective phase III RCT of statins in the treatment of cancer.

Using Elevated Cholesterol Synthesis as a Prognostic Marker in Wilms' Tumor: A Bioinformatic Analysis

Background

Wilms tumor is the most common renal malignancy of children. Identifying factors that could predict the prognosis of patients with Wilms tumor is clinically meaningful. Many studies found tumors with elevated cholesterol synthesis that are featured with dismal prognosis. Even in some clinical trials, people with excessive dietary cholesterol intake and high plasma low-density lipoprotein levels are observed to have increased risk for cancer. However, the role of cholesterol biosynthesis in Wilms tumor has not yet been well clarified.

Methods

RNA sequencing transcriptome data and all corresponding clinicopathological information used in our study were downloaded from the TARGET database. High-throughput sequencing (Fragments Per Kilobase of transcript per Million fragments mapped) data sets of 130 tumor samples and 6 normal samples were obtained for further analysis.

Results

Wilms tumor samples with higher activity of cholesterol synthesis are characterized with worse overall survival (P < 0.05). In addition, Wilms tumor samples with mitigated activity of cholesterol synthesis are featured with better dendritic cell (DC) function and cytolytic activity (P < 0.05). Furthermore, we constructed a prognosis model based on differential expressed cholesterol synthesis-related genes (DECSG), which could predict the OS of patients with Wilms tumor accurately. KEGG and GO analysis of differential expressed genes between tumor samples with high and low cholesterol synthesis indicated that DECSGs are highly enriched in “mitosis nuclear division,” “nuclear division,” “chromosome segregation,” “cell cycle,” “Spliceosome,” and “RNA transport.”

Conclusions

In conclusion, our study reported increased cholesterol synthesis in Wilms tumor predicts a worse prognosis and mitigated cytolytic activity, DC function, and MHC I signature in the tumor microenvironment. We also constructed a prognosis model for predicting the OS of patients with good accuracy, which is promising in clinical translation. Future studies should focus on the detailed mechanism that caused increasing cholesterol which promotes tumor progression and undermines patients' survival.

Association of Insulin, Metformin, and Statin with Mortality in Breast Cancer Patients

PURPOSE

This study investigated the association of insulin, metformin, and statin use with survival and whether the association was modified by the hormone receptor status of the tumor in patients with breast cancer.

MATERIALS AND METHODS

We studied 7,452 patients who had undergone surgery for breast cancer at Seoul National University Hospital from 2008 to 2015 using the nationwide claims database. Exposure was defined as a recorded prescription of each drug within 12 months before the diagnosis of breast cancer.

RESULTS

Patients with prior insulin or statin use were more likely to be older than 50 years at diagnosis and had a higher comorbidity index than those without it (p < 0.01 for both). The hazard ratio (HR) for death with insulin use was 5.7 (p < 0.01), and the effect was attenuated with both insulin and metformin exposure with an HR of 1.2 (p=0.60). In the subgroup analyses, a heightened risk of death with insulin was further prominent with an HR of 17.9 (p < 0.01) and was offset by co-administration of metformin with an HR of 1.3 (p=0.67) in patients with estrogen receptor (ER)-negative breast cancer. Statin use was associated with increased overall mortality only in patients with ER-positive breast cancer with HR for death of 1.5 (p=0.05).

CONCLUSION

Insulin or statin use before the diagnosis of breast cancer was associated with an increase in all-cause mortality. Subsequent analyses suggested that metformin or statin use may have been protective in patients with ER-negative disease, which warrants further studies.

Comparative Study of Lipophilic Statin Activity in 2D and 3D in vitro Models of Human Breast Cancer Cell Lines MDA-MB-231 and MCF-7

Introduction

Statins are a type of drugs that are used to lower cholesterol level in blood. Since the early 1990s, it has been known that statins could be beneficial in cancer therapy. However, data remain controversial, especially regarding estrogen receptors status. Despite many studies in breast cancer models in vitro, the correlations of effects of separate statins in various model systems remain unclear.

Aim

Our aim was to evaluate the anticancer activity of lovastatin, mevastatin, pitavastatin and simvastatin on different subtypes of human breast cancer (MDA-MB-231 and MCF-7 cell lines) in spatially different 2D and 3D cultures in vitro.

Materials and Methods

Cell viability was tested using MTT assay. Effect of statins on cell colony formation was evaluated by calculating breast cancer cell colony area and number. The effect on cell migration was estimated by “wound healing” assay. The activity of compounds in 3D cultures was evaluated by measuring the spheroid size changes during incubation.

Results

Among the tested statins, pitavastatin had the greatest effect on the viability of breast cancer MDA-MB-231 and MCF-7 cell lines. The mevastatin and pitavastatin mostly decreased the MDA-MB-231 and MCF-7 cell colony formation. All statins at 90% of their estimated effective concentration (EC₅₀) and simvastatin at 10% of its EC₅₀ concentration suppressed the MCF-7 cells migration in “wound healing” assay. Only higher concentrations of mevastatin and pitavastatin slowed down the MDA-MB-231 cell migration. Statins showed different activity on 3D cell cultures growth. Lovastatin and simvastatin delayed the growth of MDA-MB-231 cell spheroids, while mevastatin and pitavastatin reduced the growth of MCF-7 spheroids.

Conclusion

Statins possess different anticancer activity in human breast cancer MDA-MB-231 and MCF-7 cell cultures. Pitavastatin and simvastatin showed the highest activity in most tested assays, especially against MCF-7 cell line.

The Association of Serum Lipid Levels with Breast Cancer Risks Among Women with Breast Cancer at Felege Hiwot Comprehensive Specialized Hospital, Northwest Ethiopia

Background

Breast cancer is a malignant condition affecting about 2.1 million women worldwide. Cancer cells have increased the level of cholesterol and facilitate lipid biosynthesis and metabolism. Therefore, there is a need for assessment of serum lipid and its association with breast cancer risks.

Methods

A comparative cross-sectional study was conducted among women with breast cancer (n=23), benign breast lump (n=68) and apparently healthy control (n=91) at Felege Hiwot Comprehensive Specialized Hospital, from January to May, 2020. A convenient sampling technique and an interviewer-administered questionnaires were used to collect data. Five milliliter of fasting blood sample was collected for lipid level analysis using enzymatic colorimetric method. Data entry and analysis were done using Epi Info version 7 and SPSS version 20. One way ANOVA and logistic regression were the tools used for analysis, and a p-value of <0.05 was considered as statistically significant.

Results

The mean age of healthy control, benign and malignant breast cancer was 32.51±9.44, 33.34±10.664 and 37.65±14.345 years, respectively. The mean serum value of TG among controls, benign and malignant women was 168.67±41.616, 170.1±59.018 and 211.7±82.924 (p<0.001), respectively. The mean serum concentration of HDL-c was significantly different between the three groups (47.61±9.122, 44.69±14.479 and 38.26±7.442: p=0.004) among controls, benign and malignant, respectively. Low serum HDL-c level was significantly associated with age at parity (AOR=3.353; 95% CI=1.33, 8.436), the habit of drinking alcohol (AOR=2.125; 95% CI=1.065, 4.241) and BMI (AOR=3.555; 95% CI=1.13, 11.184). In addition, BMI (AOR: 4.54; 95% CI: 1.45, 14.21) was statistically associated with high LDL-c level.

Conclusion

The overall prevalence of dyslipidemia was high in breast cancer patients. Age at first parity, alcohol consumption and BMI were significantly associated with low serum HDL-c level.