Lycopene and the LXRα agonist T0901317 synergistically inhibit the proliferation of androgen-independent prostate cancer cells via the PPARγ-LXRα-ABCA1 pathway

Targeting cholesterol metabolism: a promising therapy strategy for cancer

Cholesterol is a crucial structural component of cell membranes, playing a vital role in maintaining membrane fluidity and stability. Cholesterol metabolism involves four interconnected processes: de novo synthesis, uptake, efflux, and esterification. Disruptions in any of these pathways can lead to imbalances in cholesterol homeostasis, which are significantly associated with cancer progression. In recent years, traditional Chinese medicine (TCM) has emerged as a comprehensive therapeutic approach with multi-target and multi-pathway effects, demonstrating significant potential in regulating cholesterol metabolism. Research has shown that certain components of TCM can modulate enzymes, transport proteins, and signaling pathways involved in cholesterol metabolism, effectively interfering with survival and migration of cancer. These mechanisms highlight the unique advantages of TCM in inhibiting tumor progression. In this review we systematically describe the execution and regulation of the four key cholesterol metabolism processes, highlights the roles of critical proteins involved, and provides a comprehensive overview of natural products from TCM that modulate cholesterol metabolism. This review provides valuable insights for the development of novel drugs and cancer therapeutic strategies targeting cholesterol metabolism.

Plant-derived terpenoids modulating cancer cell metabolism and cross-linked signaling pathways: an updated reviews

Cancer is a critical health issue that remains a predominant cause of mortality globally. It is a complex disease that may effectively regulate many signaling pathways and modify the metabolism of the body to evade the immune system. Understanding neoplastic metabolic reprogramming as a hallmark of cancer has facilitated the creation of innovative metabolism-targeted treatment strategies. Various signaling cascades, such as the PI3K/Akt/mTOR, ERK, JAK/STAT, MAPK/p38, NF-κB/Nrf2, and apoptotic pathways, are commonly involved in this process. It is now widely recognized that an inadequate response and the subsequent development of resistance are frequently caused by the highly selective blockage of these pathways in tumor cells. Consequently, to enhance the overall efficacy of anticancer agents, it is crucial to employ multi-target compounds that can concurrently inhibit multiple vital processes within tumor cells. The utilization of plant-derived bioactive compounds for this purpose is particularly promising, owing to their varied structures and numerous targets. Among these bioactive compounds, terpenoids have exhibited significant anticancer efficacy by targeting various altered signaling pathways. Thus, this review examines the terpenoid class of plant-derived compounds exhibiting potential anticancer activity, including their impact on metabolism and interconnected deregulated signaling pathways in human tumor cells. Accordingly, current research will help in the rational design and critical evaluation of innovative anticancer therapeutics utilizing plant-derived terpenoids for the modulation of cross-linked signaling pathways of cancer metabolism.

Dietary intake of tomato and lycopene, blood levels of lycopene, and risk of total and specific cancers in adults: a systematic review and dose-response meta-analysis of prospective cohort studies

Background

The association between tomato/lycopene intake and blood levels of lycopene with the risk of specific cancers were assessed in previous meta-analyses; however, no study evaluated the risk of overall cancer incidence/mortality. Therefore, the present systematic review and dose-response meta-analysis aimed to summarize available findings from prospective studies to examine the association between tomato/lycopene intake and lycopene levels with the risk of total and specific cancers and cancer-related mortality.

Methods

A comprehensive literature search was done using Scopus, PubMed, ISI Web of Science, and Google Scholar until July 2023.

Results

In total, 121 prospective studies were included in the systematic review and 119 in the meta-analysis. During the follow-up period of 2-32 years, a total of 108,574 cancer cases and 10,375 deaths occurred. High intakes and high levels of lycopene compared to low amounts were, respectively, associated with 5% (Pooled RR: 0.95, 95% CI: 0.92-0.98, I2 = 26.4%, p = 0.002) and 11% (Pooled RR: 0.89, 95% CI: 0.84-0.95, I2 = 15.0%, p < 0.001) reduction in overall cancer risk. Also, each 10 μg/dL increase in blood levels of lycopene was associated with a 5% lower risk of overall cancer. Moreover, we found a linear inverse association between dietary lycopene intake and prostate cancer risk (Pooled RR 0.99, 95% CI 0.97-1.00, I2 = 0, p = 0.045). Regarding cancer mortality, negative relationships were found with total tomato intake (Pooled RR: 0.89, 95% CI: 0.85-0.93, I2 = 65.7%, p < 0.001), lycopene intake (Pooled RR: 0.84, 95% CI: 0.81-0.86, I2 = 86.5%, p < 0.001) and lycopene levels (Pooled RR 0.76, 95% CI: 0.60-0.98, I2 = 70.9%, p = 0.031). Also, an inverse association was observed between blood lycopene levels and lung cancer mortality (Pooled RR: 0.65, 95% CI: 0.45-0.94, I2 = 0, p = 0.022).

Conclusion

Our findings show that dietary intake and blood levels of lycopene are associated with a lower risk of cancer and death due to cancer.

Clinical trial registration

CRD42023432400.

Activation of CTU2 expression by LXR promotes the development of hepatocellular carcinoma

Cytosolic thiouridylase 2 (CTU2) is an enzyme modifying transfer RNAs post-transcriptionally, which has been implicated in breast cancer and melanoma development. And we found CTU2 participated in hepatocellular carcinoma (HCC) progression here. HepG2 cells as well as xenograft nude mice model were employed to investigate the role of CTU2 in HCC development in vitro and in vivo respectively. Further, we defined CTU2 as a Liver X receptor (LXR) targeted gene, with a typical LXR element in the CTU2 promoter. CTU2 expression was activated by LXR agonist and depressed by LXR knockout. Interestingly, we also found CTU2 took part in lipogenesis by directly enhancing the synthesis of lipogenic proteins, which provided a novel mechanism for LXR regulating lipid synthesis. Meanwhile, lipogenesis was active during cell proliferation, particularly in tumor cells. Reduction of CTU2 expression was related to reduced tumor burden and synergized anti-tumor effect of LXR ligands by inducing tumor cell apoptosis and inhibiting cell proliferation. Taken together, our study identified CTU2 as an LXR target gene. Inhibition of CTU2 expression could enhance the anti-tumor effect of LXR ligand in HCC, identifying CTU2 as a promising target for HCC treatment and providing a novel strategy for the application of LXR agonists in anti-tumor effect.

Emerging Insights into Liver X Receptor α in the Tumorigenesis and Therapeutics of Human Cancers

Liver X receptor α (LXRα), a member of the nuclear receptor superfamily, is identified as a protein activated by ligands that interacts with the promoters of specific genes. It regulates cholesterol, bile acid, and lipid metabolism in normal physiological processes, and it participates in the development of some related diseases. However, many studies have demonstrated that LXRα is also involved in regulating numerous human malignancies. Aberrant LXRα expression is emerging as a fundamental and pivotal factor in cancer cell proliferation, invasion, apoptosis, and metastasis. Herein, we outline the expression levels of LXRα between tumor tissues and normal tissues via the Oncomine and Tumor Immune Estimation Resource (TIMER) 2.0 databases; summarize emerging insights into the roles of LXRα in the development, progression, and treatment of different human cancers and their diversified mechanisms; and highlight that LXRα can be a biomarker and therapeutic target in diverse cancers.

CYP27A1 inhibits proliferation and migration of clear cell renal cell carcinoma via activation of LXRs/ABCA1

Cholesterol homeostasis plays an important role in the maintenance of normal body functions. CYP27A1 is a key enzyme known to regulate cholesterol homeostasis, which catalyzes the conversion of cholesterol to 27-HC and has been implicated in the occurrence and metastasis of various cancer types. The present study aimed to explore the regulatory role of CYP27A1 in the development of clear cell renal cell carcinoma (ccRCC). In particular, the effect of CYP27A1 on the proliferation and migration of ccRCC cells was investigated. The construction of a stable 786-O cell line overexpressing CYP27A1/pLVX was mediated by lentiviral infection. The proliferative capacity was assessed using MTT and colony formation. Wound healing assay was used to measure cell migration. Production of intracellular cholesterol and 27-HC was detected by enzyme-linked immunosorbent assay. The LXRs/ABCA1 pathway of cholesterol metabolism regulation was studied by RT-qPCR and Western blotting analysis after cells were treated with stimulation agents of 27-HC or T0901317 and inhibition agents of siRNA or GSK2033. The results revealed that overexpression of CYP27A1 could increase the intracellular production of 27-HC and inhibit the proliferation and migration of 786-O cells. And the treatment of 786-O cells with 27-HC induced a similar effect. CYP27A1/27HC mediated activation of the liver X receptors (LXRs) could up-regulate the expression of ATP-binding cassette transporter A1 (ABCA1), further resulting in the reduction of intracellular cholesterol contents. All of these findings indicated a regulatory role of CYP27A1 in the proliferation and migration of ccRCC, via activating LXRs/ABCA1 to regulate cholesterol homeostasis.

Can Diet Prevent Urological Cancers? An Update on Carotenoids as Chemopreventive Agents

Urological cancers, namely prostate, bladder, kidney, testicular, and penile cancers, are common conditions that constitute almost one-quarter of all malignant diseases in men. Urological cancers tend to affect older individuals, and their development is influenced by modifiable metabolic, behavioral, and environmental risk factors. Phytochemicals may have cancer-fighting properties and protect against cancer development, slow its spread, and reduce the risk of cancer deaths in humans. This paper aims to review the current literature in regard to the effects of carotenoids in reducing urological cancer risk.

β-Carotene Oxygenase 2 Genotype Modulates the Impact of Dietary Lycopene on Gene Expression during Early TRAMP Prostate Carcinogenesis

BACKGROUND

Epidemiologic studies suggest lycopene and tomato intake are inversely associated with human prostate cancer incidence. In the genetically driven murine prostate carcinogenesis model transgenic adenocarcinoma of the mouse prostate (TRAMP), prostate cancer is inhibited by feeding of lycopene or tomatoes, and these effects are modulated by the β-carotene oxygenase 2 (Bco2) genotype.

OBJECTIVE

We sought insight into this interaction through evaluation of prostate gene expression patterns during early TRAMP carcinogenesis.

METHODS

Three-week-old TRAMP/+ or TRAMP/- × Bco2+/+ or Bco2-/- mice were fed a control, lycopene beadlet, or 10% tomato powder-containing semipurified diet (providing 0, 384 and 462 mg lycopene/kg diet, respectively) for 5 wk. Gene expression patterns were evaluated by prostate cancer- and cholesterol and lipoprotein metabolism-focused arrays at age 8 wk.

RESULTS

The TRAMP genotype profoundly alters gene expression patterns, specifically inducing pathways associated with cell survival [z-score = 2.09, -log(P value) = 29.2, p53 signaling (z-score 1.13, -log(P value) = 13.5], and phosphatidylinositol-3 kinase (PI3K)/protein kinase B (AKT) signaling [z-score = 0.302, -log(P value) = 12.1], while repressing phosphatase and tensin homolog (PTEN) signaling [(z-score = -0.905, -log(P value) = 12.3], cholesterol synthesis [z-score = -1.941, -log(P-value) = 26.2], and LXR/RXR pathway activation [z-score = -1.941, -log(P value) = 23.1]. In comparison, lycopene- and tomato-feeding modestly modulate strong procarcinogenic TRAMP signaling. Lycopene decreased gene expression related to carcinogenesis [ Nkx3-1(NK3 homeobox 1)], tomato feeding increased expression of a gene involved in circadian regulation [Arntl (aryl hydrocarbon receptor nuclear translocator like)], and tomato and/or lycopene increased expression of genes involved in lipid metabolism [Fasn (fatty acid synthase), Acaca(acetyl-CoA carboxylase alpha), Srebf1 (sterol regulatory element binding transcription factor 1), Hmgcr (3-hydroxy-3-methylglutaryl-coA reductase), and Ptgs1 (prostaglandin-endoperoxide synthase 1)] (all P < 0.05). The impact of Bco2 genotype was limited to a subset of lycopene-impacted genes [Apc (adenomatous polyposis coli), Mto1 (mitochondrial TRNA translation optimization 1), Nfkb1 (nuclear factor kappa B subunit 1), andRbm39 (RNA binding motif protein 39)].

CONCLUSIONS

The TRAMP genotype strongly impacts procarcinogenic gene expression prior to emergence of histopathologic disease. Dietary tomato and lycopene modestly temper these processes, while Bco2 genotype has a limited impact at this early stage. These observed patterns provide insight into the complex interactions between a dietary variable, here tomatoes and lycopene, genes impacting nutrient metabolism, and their modulating influences on oncogene-driven prostate carcinogenesis. These findings provide further mechanistic support, consistent with cancer outcomes in rodents experiments and human epidemiologic studies.

Curcuma oil ameliorates benign prostatic hyperplasia through suppression of the nuclear factor-kappa B signaling pathway in rats

ETHNO PHARMACOLOGICAL RELEVANCE

Curcuma longa L is traditionally used as an anti-inflammatory remedy in Chinese traditional medicine. Curcuma oil (CO), a lipophilic fraction from Curcuma longa L. has been reported to have anti-proliferative, anti-inflammatory and anti-oxidant activities. However, CO has never been investigated for its possible therapeutic effects on benign prostatic hyperplasia (BPH).

AIMS OF THE STUDY

The study is thus to determine the therapeutic effects of curcuma oil on BPH and also the possible mechanism (s) of action.

MATERIALS &METHODS

A BPH-1 cell line and Sprague Dawley (SD) rats were used to establish BPH models in vitro and in vivo, respectively. Rats were treated by CO (2.4, 7.2 mg/kg/i.g.) and finasteride (5 mg/kg/i.g.), respectively. Histological changes were examined by hematoxylin and eosin (H&E) staining. Protein expression was analyzed for 5α-reductase (5AR), dihydrotestosterone (DHT), interleukin (IL)-1β, IL-6 and tumor necrosis factor (TNF)-α by ELISA. Ki-67, Caspase-8,-9 and -3 expressions were evaluated via immunohistochemistry (IHC).

RESULTS

CO effectively induced apoptosis in BPH-1 cells. BPH was successfully established by administration of testosterone propionate (TP) in rats, which upregulated both 5α-reductase expression and DHT production. Importantly, TP establishment significantly stimulated the phosphorylation of p65, one subunit of NF-κB, thus led to activation of the NF-κB signaling pathway in prostatic tissues of rats. In turn, the activation of NF-κB pathway induced concomitant upregulation of proinflammatory factors IL-1β, IL-6, TNF-α, and COX-2 and significant increase of the Bcl2/Bax expression ratio for enhanced cell survival, contributing to the initiation and progression of BPH in rats. Notably, CO therapy significantly decreased prostate weight and hyperplasia in BPH-induced animals. Also CO was found to suppress the expression of 5α-reductase and thus the production of DHT, which is essential for the amelioration of BPH. More importantly, CO was shown to suppress the activation of NF-κB pathway through decreasing the expression of phosphorylated p65 and consequently reduced the inflammatory responses and cell survival in prostatic tissues, leading to the inhibition of BPH development in rats.

CONCLUSION

Curcuma oil is very effective for ameliorating BPH in rats. The underlying mechanisms involve in reduced inflammatory responses and cell survival through suppression of the NF-κB signaling pathway by CO in prostatic tissues.

PPAR-γ Modulators as Current and Potential Cancer Treatments

Worldwide, cancer has become one of the leading causes of mortality. Peroxisome Proliferator-Activated Receptors (PPARs) is a family of critical sensors of lipids as well as regulators of diverse metabolic pathways. They are also equipped with the capability to promote eNOS activation, regulate immunity and inflammation response. Aside from the established properties, emerging discoveries are also made in PPAR's functions in the cancer field. All considerations are given, there exists great potential in PPAR modulators which may hold in the management of cancers. In particular, PPAR-γ, the most expressed subtype in adipose tissues with two isoforms of different tissue distribution, has been proven to be able to inhibit cell proliferation, induce cell cycle termination and apoptosis of multiple cancer cells, promote intercellular adhesion, and cripple the inflamed state of tumor microenvironment, both on transcriptional and protein level. However, despite the multi-functionalities, the safety of PPAR-γ modulators is still of clinical concern in terms of dosage, drug interactions, cancer types and stages, etc. This review aims to consolidate the functions of PPAR-γ, the current and potential applications of PPAR-γ modulators, and the challenges in applying PPAR-γ modulators to cancer treatment, in both laboratory and clinical settings. We sincerely hope to provide a comprehensive perspective on the prospect of PPAR-γ applicability in the field of cancer treatment.

Recent Progress in Discovering the Role of Carotenoids and Their Metabolites in Prostatic Physiology and Pathology with a Focus on Prostate Cancer-A Review-Part I: Molecular Mechanisms of Carotenoid Action

Among the vast variety of plant-derived phytochemicals, the group of carotenoids has continuously been investigated in order to optimize their potential application in the area of dietary intervention and medicine. One organ which has been especially targeted in many of these studies and clinical trials is the human prostate. Without doubt, carotenoids (and their endogenous derivatives—retinoids and other apo-carotenoids) are involved in intra- and intercellular signaling, cell growth and differentiation of prostate tissue. Due to the accumulation of new data on the role of different carotenoids such as lycopene (LC) and β-carotene (BC) in prostatic physiology and pathology, the present review aims to cover the past ten years of research in this area. Data from experimental studies are presented in the first part of the review, while epidemiological studies are disclosed and discussed in the second part. The objective of this compilation is to emphasize the present state of knowledge regarding the most potent molecular targets of carotenoids and their main metabolites, as well as to propose promising carotenoid agents for the prevention and treatment of prostatic diseases.

Investigating into anti-cancer potential of lycopene: Molecular targets

Lycopene, the main pigment of tomatoes, possess the strongest antioxidant activity among carotenoids. Lycopene has unique structure and chemical properties. We searched the literature, via PubMed, Embase, Web of Science and Google database so on to screen citations from inception to Oct 2020 for inclusion in this study. We found that as a common phytochemical, it did not attract much attention in the past few years. However, recent studies have indicated that, in addition to antioxidant activity and the second stage of detoxification, the anticancer of lycopene is also considered to be an important determinant of tumor development including the inhibition of cell proliferation, inhibition of cell cycle progression, induction of apoptosis, inhibition of cell invasion, angiogenesis and metastasis. The effect mechanisms of lycopene are related to the regulation of several signal transduction pathways, such as PI3K/Akt pathway, modulation of insulin-like growth factors system, the suppression of activity of sex steroid hormones, the modification of relevant gene expression, and the alteration of mitochondrial function. These novel findings have suggested that lycopene acts as a promising functional natural pigment, and may be associated with a decreased risk of different types of cancer. This review presents the latest knowledge with respect to its molecular mechanisms and its molecular targets of the inhibitory effects on carcinogenesis.

Mitofusin-2: A New Mediator of Pathological Cell Proliferation

Cell proliferation is an important cellular process for physiological tissue homeostasis and remodeling. The mechanisms of cell proliferation in response to pathological stresses are not fully understood. Mitochondria are highly dynamic organelles whose shape, number, and biological functions are modulated by mitochondrial dynamics, including fusion and fission. Mitofusin-2 (Mfn-2) is an essential GTPase-related mitochondrial dynamics protein for maintaining mitochondrial network and bioenergetics. A growing body of evidence indicates that Mfn-2 has a potential role in regulating cell proliferation in various cell types. Here we review these new functions of Mfn-2, highlighting its crucial role in several signaling pathways during the process of pathological cell proliferation. We conclude that Mfn-2 could be a new mediator of pathological cell proliferation and a potential therapeutic target.

Effects of phytochemicals on macrophage cholesterol efflux capacity: Impact on atherosclerosis

High-density lipoprotein cholesterol (HDL) is the major promoter of reverse cholesterol transport and efflux of excess cellular cholesterol. The functions of HDL, such as cholesterol efflux, are associated with cardiovascular disease rather than HDL levels. We have reviewed the evidence base on the major classes of phytochemicals, including polyphenols, alkaloids, carotenoids, phytosterols, and fatty acids, and their effects on macrophage cholesterol efflux and its major pathways. Phytochemicals show the potential to improve the efficiency of each of these pathways. The findings are mainly in preclinical studies, and more clinical research is warranted in this area to develop novel clinical applications.

1, 6-O, O-Diacetylbritannilactone from Inula britannica Induces Anti-Tumor Effect on Oral Squamous Cell Carcinoma via miR-1247-3p/LXRα/ABCA1 Signaling

Introduction

Oral squamous cell carcinoma (OSCC) is the most prevalent malignancy affecting the oral cavity and is associated with severe morbidity and high mortality. 1, 6-O, O-Diacetylbritannilactone (OODBL) isolated from the medicinal herb of Inula britannica has various biological activities such as anti-inflammation and anti-cancer. However, the effect of OODBL on OSCC progression remains unclear. Here, we were interested in the function of OODBL in the development of OSCC.

Methods

The effect of OODBL on OSCC progression was analyzed by MTT assays, colony formation assays, transwell assays, apoptosis analysis, cell cycle analysis, and in vivo tumorigenicity analysis. The mechanism investigation was performed by qPCR assays, Western blot analysis, and luciferase reporter gene assays.

Results

We found that OODBL inhibits the proliferation of OSCC cells in vitro. Moreover, the migration and invasion were attenuated by OODBL treatment in the OSCC cells. OODBL arrested cells at the G0/G1 phase and induced cell apoptosis. OODBL was able to up-regulate the expression of LXRα, ABCA1, and ABCG1 in the system. In addition, OODBL activated LXRα/ABCA1 signaling by targeting miR-1247-3p. Furthermore, the expression levels of cytochrome c in the cytoplasm, cleaved caspase-9, and cleaved caspase-3 were dose-dependently reduced by OODBL. Besides, OODBL increased the expression ratio of Bax to Bcl-2. Moreover, OODBL repressed tumor growth of OSCC cells in vivo.

Discussion

Thus, we conclude that OODBL inhibits OSCC progression by modulating miR-1247-3p/LXRα/ABCA1 signaling. Our finding provides new insights into the mechanism by which OODBL exerts potent anti-tumor activity against OSCC. OODBL may be a potential anti-tumor candidate, providing a novel clinical treatment strategy of OSCC.

Silencing KIF18B enhances radiosensitivity: identification of a promising therapeutic target in sarcoma

Background

Sarcomas are rare heterogeneous tumours, derived from primitive mesenchymal stem cells, with more than 100 distinct subtypes. Radioresistance remains a major clinical challenge for sarcomas, demanding urgent for effective biomarkers of radiosensitivity.

Methods

The radiosensitive gene Kinesin family member 18B (KIF18B) was mined through bioinformatics with integrating of 15 Gene Expression Omnibus (GEO) datasets and The Cancer Genome Atlas (TCGA) database. We used radiotherapy-sh-KIF18B combination to observe the anti-tumour effect in sarcoma cells and subcutaneous or orthotopic xenograft models. The KIF18B-sensitive drug T0901317 (T09) was further mined to act as radiosensitizer using the Genomics of Drug Sensitivity in Cancer (GDSC) database.

Findings

KIF18B mRNA was significantly up-regulated in most of the subtypes of bone and soft tissue sarcoma. Multivariate Cox regression analysis showed that KIF18B high expression was an independent risk factor for prognosis in sarcoma patients with radiotherapy. Silencing KIF18B or using T09 significantly improved the radiosensitivity of sarcoma cells, delayed tumour growth in subcutaneous and orthotopic xenograft model, and elongated mice survival time. Furthermore, we predicted that T09 might bind to the structural region of KIF18B to exert radiosensitization.

Interpretation

These results indicated that sarcomas with low expression of KIF18B may benefit from radiotherapy. Moreover, the radiosensitivity of sarcomas with overexpressed KIF18B could be effectively improved by silencing KIF18B or using T09, which may provide promising strategies for radiotherapy treatment of sarcoma.

Fundings

A full list of funding can be found in the Funding Sources section.

Shedding light on the roles of liver X receptors in cancer by using chemical probes

Nuclear receptors, liver X receptor-α (LXRα; NR1H3) and liver X receptor-β (LXRβ; NR1H2), are considered master regulators of lipid homeostasis. During the last couple of decades, their pivotal roles in several physiological and pathological processes ranging from energy supply, immunity, cardiovascular, neurodegenerative disorders and cancer have been highlighted. In this review, the main results achieved during more recent years about our understanding of the LXR involvement in cancer has been mainly obtained using small-molecule chemical probes. Remarkably, all these probes, albeit having different structure and biological properties, have a well demonstrated anti-tumoral activity arising from LXR modulation, indicating a high potential of LXR targeting for the treatment of cancer. LINKED ARTICLES: This article is part of a themed issue on Oxysterols, Lifelong Health and Therapeutics. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v178.16/issuetoc.

Potential inhibitory effect of lycopene on prostate cancer

Studying prostate cancer is important due to its high annual incidences and mortality rates in the world. Although prostate cancer mortality rates are reduced using new therapy, complicated routes and side effects of these current drugs require a daily available treatment for prevention. Lycopene is a natural, prominent, and effective product which has a high value in diet. The anti-cancer effect, non-toxicity, safety and preventive or therapeutic roles of lycopene have been investigated in several studies. In the current review, we have collected information about the anti-cancer, anti-progressive and apoptotic effects of lycopene on prostate cancer. This article is a summary of the most important original and review articles on lycopene and its anticancer effects that are systematically categorized and presents information about the molecular structure, different sources, biological functions, and its in-vivo and in-vitro effects of lycopene on variety of cancerous and normal cells. The clinical studies provide a clear image for continuous use of this adjunctive dietary for different type of cancers, especially prostate cancer in men. In addition, this article discusses the various molecular pathways activated by lycopene that eventually prevent or suppress cancer. Lycopene has been found to effectively suppress the progression and proliferation, arrest in-cell cycle, and induce apoptosis of prostate cancer cells in both in-vivo and in-vitro conditions. Additionally, lycopene showed that it could modulate the signaling pathways and their protein for the treatment or prevention of prostate cancer.

Regulation mechanism of silkworm pupa oil PUFAs on cholesterol metabolism in hepatic cell L-02

BACKGROUND

Silkworm pupa oil polyunsaturated fatty acid (SPO PUFA) has been confirmed to have a cholesterol-lowering function.

METHODS AND RESULTS

The effect of SPO PUFA and its main component, α-linolenic acid (ALA), on the metabolism of cholesterol and its regulation was investigated. The model of lipid denatured cells were constructed to carry out lipid accumulation, cholesterol metabolism and transformation. Real-time PCR and western blots were also used to analyze the expression levels of related genes and proteins to investigate the cholesterol efflux regulation mechanism. The data indicated that SPO PUFA and ALA dose-dependently decreased intracellular total cholesterol (TC) and enhanced total bile acid (TBA). They could also promote cholesterol removal by enhancing bile acid secretion and by upregulating genes LXRα, PPARγ, ABCA1, ABCG1, and CYP7A1, which were regulated by LXRα/PPARγ-ABCA1/ABCG1-CYP7A1 nuclear receptor signal pathways.

CONCLUSIONS

This study is of great significance in maintaining the balance of cholesterol and lipid metabolism, and in reducing the risk of steatohepatitis. © 2019 Society of Chemical Industry.

Impact of natural products on the cholesterol transporter ABCA1

ETHNOPHARMACOLOGICAL RELEVANCE

In different countries and areas of the world, traditional medicine has been and is still used for the treatment of various disorders, including chest pain or liver complaints, of which we now know that they can be linked with altered lipid and cholesterol homeostasis. As ATP-binding cassette transporter A1 (ABCA1) plays an essential role in cholesterol metabolism, its modulation may be one of the molecular mechanisms responsible for the experienced benefit of traditional recipes. Intense research activity has been dedicated to the identification of natural products from traditional medicine that regulate ABCA1 expression.

AIMS OF THE REVIEW

This review surveys natural products, originating from ethnopharmacologically used plants, fungi or marine sources, which influence ABCA1 expression, providing a reference for future study.

MATERIALS AND METHODS

Information on regulation of ABCA1 expression by natural compounds from traditional medicine was extracted from ancient and modern books, materia medica, and electronic databases (PubMed, Google Scholar, Science Direct, and ResearchGate).

RESULTS

More than 60 natural compounds from traditional medicine, especially traditional Chinese medicine (TCM), are reported to regulate ABCA1 expression in different in vitro and in vivo models (such as cholesterol efflux and atherosclerotic animal models). These active compounds belong to the classes of polyketides, terpenoids, phenylpropanoids, tannins, alkaloids, steroids, amino acids and others. Several compounds appear very promising in vivo, which need to be further investigated in animal models of diseases related to ABCA1 or in clinical studies.

CONCLUSION

Natural products from traditional medicine constitute a large promising pool for compounds that regulate ABCA1 expression, and thus may prevent/treat diseases related to cholesterol metabolism, like atherosclerosis or Alzheimer's disease. In many cases, the molecular mechanisms of these natural products remain to be investigated.

Modulation of dysregulated cancer metabolism by plant secondary metabolites: A mechanistic review

Several signaling pathways and basic metabolites are responsible for the control of metabolism in both normal and cancer cells. As emerging hallmarks of cancer metabolism, the abnormal activities of these pathways are of the most noticeable events in cancer. This altered metabolism expedites the survival and proliferation of cancer cells, which have attracted a substantial amount of interest in cancer metabolism. Nowadays, targeting metabolism and cross-linked signaling pathways in cancer has been a hot topic to investigate novel drugs against cancer. Despite the efficiency of conventional drugs in cancer therapy, their associated toxicity, resistance, and high-cost cause limitations in their application. Besides, considering the numerous signaling pathways cross-linked with cancer metabolism, discovery, and development of multi-targeted and safe natural compounds has been a high priority. Natural secondary metabolites have exhibited promising anticancer effects by targeting dysregulated signaling pathways linked to cancer metabolism. The present review reveals the metabolism and cross-linked dysregulated signaling pathways in cancer. The promising therapeutic targets in cancer, as well as the critical role of natural secondary metabolites for significant anticancer enhancements, have also been highlighted to find novel/potential therapeutic agents for cancer treatment.

Therapeutic potential of PPARγ natural agonists in liver diseases

Peroxisome proliferator‐activated receptor gamma (PPARγ) is a vital subtype of the PPAR family. The biological functions are complex and diverse. PPARγ plays a significant role in protecting the liver from inflammation, oxidation, fibrosis, fatty liver and tumours. Natural products are a promising pool for drug discovery, and enormous research effort has been invested in exploring the PPARγ‐activating potential of natural products. In this manuscript, we will review the research progress of PPARγ agonists from natural products in recent years and probe into the application potential and prospects of PPARγ natural agonists in the therapy of various liver diseases, including inflammation, hepatic fibrosis, non‐alcoholic fatty liver and liver cancer.

Role of cholesterol homeostasis and its efflux pathways in cancer progression

Tumor cells show high avidity for cholesterol in order to support their inherent nature to divide and proliferate. This results in the rewiring of cholesterol homeostatic pathways by influencing not only de novo synthesis but also uptake or efflux pathways of cholesterol. Recent findings have pointed towards the importance of cholesterol efflux in tumor pathogenesis. Cholesterol efflux is the first and foremost step in reverse cholesterol transport and any perturbation in this pathway may lead to the accumulation of intracellular cholesterol, thereby altering the cellular equilibrium. This review addresses the different mechanisms of cholesterol efflux from the cell and highlights their role and regulation in context to tumor development. There are four different routes by which cholesterol can be effluxed from the cell namely, 1) passive diffusion of cholesterol to mature HDL particles, 2) SR-B1 mediated facilitated diffusion, 3) Active efflux to apo A1 via ABCA1 and 4) ABCG1 mediated efflux to mature HDL. These molecular players facilitating cholesterol efflux are engaged in a complex interplay with different signaling pathways. Thus, an understanding of the efflux pathways, their regulation and cross-talk with signaling molecules may provide novel prognostic markers and therapeutic targets to combat the onset of carcinogenesis.

TO901317 inhibits the development of hepatocellular carcinoma by LXRα/Glut1 decreasing glycometabolism

This study was conducted to observe the effect and possible mechanism of TO901317 in vivo and in vitro to provide a new basis for the targeted therapy of hepatocellular carcinoma (HCC). The expressions of liver X receptor (LXR)-α, glucose transporter (Glut)-1, proliferating cell nuclear antigen (PCNA), and matrix metalloproteinase (MMP)-9 were analyzed from HCC public database (NCBI PubMed database). The result showed that LXRα was downregulated, whereas Glut1, PCNA, and MMP9 were upregulated in human HCC compared with normal liver. Furthermore, LXRα mRNA was negatively correlated with Glut1 mRNA. At the same time, HCC cells were cultivated in vitro and axillary injected in nude mice to establish the xenograft model. The xenograft in the TO901317-treated group was slower and smaller than the control group. The protein expression of LXRα, Glut1, and MMP9 could be detected by Western blot and glucose level. As a result, TO901317 could inhibit the cell proliferation of HCC in a dose-dependent manner by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. With the increase of TO901317 concentration, the cellular glucose concentration and ATP level were gradually decreased. Western blot results showed TO901317 could upregulate LXRα expression but downregulate MMP9 and Glut1 expression. Transwell and wound-healing analysis confirmed that, by increasing the concentration of TO901317, the cell invasion and migration were both decreased. LXRα small-interfering RNA (siRNA) could relieve the suppression effect of TO901317 on the cell invasion and migration and the expression of LXRα, Glut1, and MMP9. The glucose concentration was also raised. TO901317 could repress the progress of HCC cells by reducing the glucose concentration, upregulating LXRα expression, but downregulating the expression of Glut1 and MMP9. NEW & NOTEWORTHY This subject confirmed that TO901317, a specific liver X receptor agonist, could inhibit the progression of liver cancer through upregulating liver X receptor-α, downregulating the expression of glucose transporter-1 and matrix metalloproteinase-9, and decreasing the glucose content in SMMC-7721 and HepG2 cells.

Bioactivities of phytochemicals present in tomato

Tomato is a wonder fruit fortified with health-promoting phytochemicals that are beneficial in preventing important chronic degenerative disorders. Tomato is a good source of phenolic compounds (phenolic acids and flavonoids), carotenoids (lycopene, α, and β carotene), vitamins (ascorbic acid and vitamin A) and glycoalkaloids (tomatine). Bioactive constituents present in tomato have antioxidant, anti-mutagenic, anti-proliferative, anti-inflammatory and anti-atherogenic activities. Health promoting bioactivities of tomatoes make them useful ingredient for the development of functional foods. Protective role of tomato (lycopene as a potent antioxidant) in humans against various degenerative diseases are known throughout the world. Intake of tomato is inversely related to the incidence of cancer, cardiovascular diseases, ageing and many other health problems. Bioavailability of phytoconstituents in tomato is generally not affected by routine cooking processes making it even more beneficial for human consumption. The present review provides collective information of phytochemicals in tomato along with discussing their bioactivities and possible health benefits.

Efatutazone and T0901317 exert synergistically therapeutic effects in acquired gefitinib-resistant lung adenocarcinoma cells

The development of acquired EGFR‐TKI therapeutic resistance is still a serious clinical problem in the management of lung adenocarcinoma. Peroxisome proliferator activated receptor gamma (PPARγ) agonists may exhibit anti‐tumor activity by transactivating genes which are closely associated with cell proliferation, apoptosis, and differentiation. However, it remains not clear whether efatutazone has similar roles in lung adenocarcinoma cells of gefitinib resistant such as HCC827‐GR and PC9‐GR. It has been demonstrated by us that efatutazone prominently increased the mRNA and protein expression of PPARγ, liver X receptor alpha (LXRα),as well as ATP binding cassette subfamily A member 1 (ABCA1). In the presence of GW9662 (a specific antagonist of PPARγ) or GGPP (a specific antagonist of LXRα), efatutazone (40 μmol/L) restored the proliferation of both HCC827‐GR and PC9‐GR cells and obviously inhibited the increased protein and mRNA expression of PPAR‐gamma, LXR‐alpha, and ABCA1 induced by efatutazone. LXRα knockdown by siRNA (si‐LXRα) significantly promoted the HCC827‐GR and PC9‐GR cells proliferation, whereas incubation efatutazone with si‐LXRα restored the proliferation ability compared with the control group. In addition, combination of efatutazone and LXRα agonist T0901317 showed a synergistic therapeutic effect on lung adenocarcinoma cell proliferation and PPAR gamma, LXR A and ABCA1 protein expression. These results indicate that efatutazone could inhibit the cells proliferation of HCC827‐GR and PC9‐GR through PPARγ/LXRα/ABCA1 pathway, and synergistic therapeutic effect is achieved when combined with T0901317.

Suppressive effects of lycopene and β-carotene on the viability of the human esophageal squamous carcinoma cell line EC109

The molecular mechanisms underlying the chemopreventive effects of carotenoids in different types of cancer are receiving increasing attention. In the present study, the role of peroxisome proliferator-activated receptor γ (PPARγ) in the effect of lycopene and β-carotene on the viability of EC109 human esophageal squamous carcinoma cells was investigated. The viability of EC109 cells was evaluated using MTT assays. The effects of lycopene and β-carotene on the expression of PPARγ, p21^WAF1/CIP1, cyclin D1 and cyclooxygenase-2 (COX-2) were analyzed by western blotting. Lycopene and β-carotene (5-40 µM) dose- and time-dependently reduced the viability of the EC109 cells. GW9662, an irreversible PPARγ antagonist, partly attenuated the decrease in EC109 cell viability induced by these carotenoids. Lycopene and β-carotene treatments upregulated the expression of PPARγ and p21^WAF1/CIP1, and downregulated the expression of cyclin D1 and COX-2. These modulatory effects of the carotenoid treatments were suppressed by GW9662, suggesting that the inhibition of EC109 cell viability by lycopene and β-carotene involves PPARγ signaling pathways and the modulation of p21^WAF1/CIP1, cyclin D1 and COX-2 expression.

Andrographolide Inhibits Oxidized LDL-Induced Cholesterol Accumulation and Foam Cell Formation in Macrophages

oxLDL is involved in the pathogenesis of atherosclerotic lesions through cholesterol accumulation in macrophage foam cells. Andrographolide, the bioactive component of Andrographis paniculata, possesses several biological activities such as anti-inflammatory, anti-oxidant, and anticancer functions. Scavenger receptors (SRs), including class A SR (SR-A) and CD36, are responsible for the internalization of oxLDL. In contrast, receptors for reverse cholesterol transport, including ABCA1 and ABCG1, mediate the efflux of cholesterol from macrophage foam cells. Transcription factor liver X receptor [Formula: see text] (LXR[Formula: see text] plays a key role in lipid metabolism and inflammation as well as in the regulation of ABCA1 and ABCG1 expression. Because of the contribution of inflammation to macrophage foam cell formation and the potent anti-inflammatory activity of andrographolide, we hypothesized that andrographolide might inhibit oxLDL-induced macrophage foam cell formation. The results showed that andrographolide reduced oxLDL-induced lipid accumulation in macrophage foam cells. Andrographolide decreased the mRNA and protein expression of CD36 by inducing the degradation of CD36 mRNA; however, andrographolide had no effect on SR-A expression. In contrast, andrographolide increased the mRNA and protein expression of ABCA1 and ABCG1, which were dependent on LXR[Formula: see text]. Andrographolide enhanced LXR[Formula: see text] nuclear translocation and DNA binding activity. Treatment with the LXR[Formula: see text] antagonist GGPP and transfection with LXR[Formula: see text] siRNA reversed the ability of andrographolide to stimulate ABCA1 and ABCG1 protein expression. In conclusion, inhibition of CD36-mediated oxLDL uptake and induction of ABCA1- and ABCG1-dependent cholesterol efflux are two working mechanisms by which andrographolide inhibits macrophage foam cell formation, which suggests that andrographolide could be a potential candidate to prevent atherosclerosis.

Dietary Carotenoid Intakes and Prostate Cancer Risk: A Case-Control Study from Vietnam

The incidence of prostate cancer has increased in Vietnam, but there have been few studies of the risk factors associated with this change. This retrospective case-control study investigated the relation of the intake of carotenoids and their food sources to prostate cancer risk. A sample of 652 participants (244 incident prostate cancer patients, aged 64-75 years, and 408 age frequency-matched controls) were recruited in Ho Chi Minh City during 2013-2015. The habitual diet was ascertained with a validated food-frequency questionnaire, and other factors including demographic and lifestyle characteristics were assessed via face-to-face interviews by trained nurses. Multivariate-adjusted odds ratios (OR) and 95% confidence intervals (CI) were estimated using unconditional logistic regression models. The risk of prostate cancer decreased with increasing intakes of lycopene, tomatoes, and carrots; the respective ORs (95% CIs) were 0.46 (0.27, 0.77), 0.39 (0.23, 0.66), and 0.35 (0.21, 0.58), when comparing the highest with the lowest tertile of intake (p for trend < 0.01). No statistically significant associations were found for the intake of α-carotene, β-carotene, β-cryptoxanthin, lutein, zeaxanthin, and major food sources of carotenoids. In conclusion, Vietnamese men with a higher intake of lycopene, tomatoes, and carrots may have a lower risk of prostate cancer. However, large prospective studies are needed in this population to confirm this finding.

PPARγ agonist efatutazone and gefitinib synergistically inhibit the proliferation of EGFR-TKI-resistant lung adenocarcinoma cells via the PPARγ/PTEN/Akt pathway

Development of acquired resistance to EGFR-TKI therapy continues to be a serious clinical problem in Lung adenocarcinoma management. Peroxisome proliferator-activated receptor gamma (PPARγ) agonists demonstrate anti-tumor activity likely via transactivating genes that regulate cell proliferation, differentiation and apoptosis. Efatutazone, a novel later generation PPARγ agonist, selectively activates PPARγ target genes and has antiproliferative effects in a range of malignancies. However, the exact function and molecular mechanism of PPARγ agonists efatutazone in EGFR-TKI gefitinib-resistance of Lung adenocarcinoma has not been determined. In this study, we studied the development of acquired resistance to an EGFR-TKI gefitinib in lung adenocarcinoma cells and investigated the antiproliferative effects of efatutazone in the acquired resistant cells. The treatment of gefitinib-resistant cells with efatutazone reduced the growth of gefitinib-resistant cells in a dose- and time-dependent manner, and facilitated the anti-proliferative effects of gefitinib. Mechanistic investigations suggested that efatutazone acted by upregulating protein expression of PPARγ, phosphatase and tensin homolog (PTEN), inactivating the Akt pathway, followed by dephosphorylation of p21Cip1 at Thr145 without affecting the transcriptional levels. Our results suggested that efatutazone, alone or in combination with gefitinib, might offer therapeutic effects in lung adenocarcinoma.

Vitamin K epoxide reductase regulation of androgen receptor activity

Long-term use of warfarin has been shown to be associated with a reduced risk of prostate cancer. Warfarin belongs to the vitamin K antagonist class of anticoagulants, which inhibit vitamin K epoxide reductase (VKOR). The vitamin K cycle is primarily known for its role in γ-carboxylation, a rare post-translational modification important in blood coagulation. Here we show that warfarin inhibits the transcriptional activity of the androgen receptor (AR), an important driver of prostate cancer development and progression. Warfarin treatment or knockdown of its target VKOR inhibits the activity of AR both in cell lines and in mouse prostate tissue. We demonstrate that AR can be γ-carboxylated, and mapped the γ-carboxylation to glutamate residue 2 (E2) using mass spectrometry. However, mutation of E2 and other glutamates on AR failed to suppress the effects of warfarin on AR suggesting that inhibition of AR is γ-carboxylation independent. To identify pathways upstream of AR signaling that are affected by warfarin, we performed RNA-seq on prostates of warfarin-treated mice. We found that warfarin inhibited peroxisome proliferator-activated receptor gamma (PPARγ) signaling, which in turn, inhibited AR signaling. Although warfarin is unfit for use as a chemopreventative due to its anticoagulatory effects, our data suggest that its ability to reduce prostate cancer risk is independent of its anticoagulation properties. Furthermore, our data show that warfarin inhibits PPARγ and AR signaling, which suggests that inhibition of these pathways could be used to reduce the risk of developing prostate cancer.

WOMEN IN CANCER THEMATIC REVIEW: New roles for nuclear receptors in prostate cancer

Prostate cancer has, for decades, been treated by inhibiting androgen signalling. This is effective in the majority of patients, but inevitably resistance develops and patients progress to life-threatening metastatic disease - hence the quest for new effective therapies for 'castrate-resistant' prostate cancer (CRPC). Studies into what pathways can drive tumour recurrence under these conditions has identified several other nuclear receptor signalling pathways as potential drivers or modulators of CRPC.The nuclear receptors constitute a large (48 members) superfamily of transcription factors sharing a common modular functional structure. Many of them are activated by the binding of small lipophilic molecules, making them potentially druggable. Even those for which no ligand exists or has yet been identified may be tractable to activity modulation by small molecules. Moreover, genomic studies have shown that in models of CRPC, other nuclear receptors can potentially drive similar transcriptional responses to the androgen receptor, while analysis of expression and sequencing databases shows disproportionately high mutation and copy number variation rates among the superfamily. Hence, the nuclear receptor superfamily is of intense interest in the drive to understand how prostate cancer recurs and how we may best treat such recurrent disease. This review aims to provide a snapshot of the current knowledge of the roles of different nuclear receptors in prostate cancer - a rapidly evolving field of research.

Phosphatidylcholine kinetics in neonatal rat lungs and the effects of rhuKGF and betamethasone

Surfactant, synthesized by type II pneumocytes (PN-II), mainly comprises phosphatidylcholine (PC) and is essential to prevent neonatal respiratory distress. Furthermore, PC is essential to lung tissue growth and maintenance as a membrane component. Recent findings suggest that the lung contributes to systemic lipid homeostasis via PC export through ABC-A1 transporter expression. Hence it is important to consider pharmacological interventions in neonatal lung PC metabolism with respect to such export. Five-day-old rats were treated with carrier (control), intraperitoneal betamethasone, subcutaneous recombinant human keratinocyte growth factor (rhuKGF), or their combination for 48 h. Animals were intraperitoneally injected with 50 mg/kg [D9-methyl]choline chloride 1.5, 3.0, and 6.0 h before death at day 7, and lung lavage fluid (LLF) and tissue were harvested. Endogenous PC, D9-labeled PC species, and their water-soluble precursors (D9-)choline and (D9-)phosphocholine were determined by tandem mass spectrometry. Treatment increased secreted and tissue PC pools but did not change equilibrium composition of PC species in LLF. However, all treatments increased specific surfactant components in tissue. In control rats, peak D9-PC in lavaged lung was reached after 3 h and was decreased at 6 h. Only 13% of this net loss in lavaged lung was found in LLF. Such decrease was not present in lungs treated with betamethasone and/or with rhuKGF. D9-PC loss at 3–6 h and PC synthesis calculated from D9 enrichment of phosphocholine indicated that daily synthesis rate is higher than total pool size. We conclude that lung tissue contributes to systemic PC homeostasis in neonatal rats, which is altered by glucocorticoid and rhuKGF treatment.

Effects of pomegranate peel polyphenols on lipid accumulation and cholesterol metabolic transformation in L-02 human hepatic cells via the PPARγ-ABCA1/CYP7A1 pathway

PPPs, PC and PEA in different concentrations were found to decrease the total cholesterol (TC) content and increase the total bile acid (TBA) content of a human hepatic cell model, and so possess a lipid-lowering effect.

Genomic instability in human cancer: Molecular insights and opportunities for therapeutic attack and prevention through diet and nutrition

Genomic instability can initiate cancer, augment progression, and influence the overall prognosis of the affected patient. Genomic instability arises from many different pathways, such as telomere damage, centrosome amplification, epigenetic modifications, and DNA damage from endogenous and exogenous sources, and can be perpetuating, or limiting, through the induction of mutations or aneuploidy, both enabling and catastrophic. Many cancer treatments induce DNA damage to impair cell division on a global scale but it is accepted that personalized treatments, those that are tailored to the particular patient and type of cancer, must also be developed. In this review, we detail the mechanisms from which genomic instability arises and can lead to cancer, as well as treatments and measures that prevent genomic instability or take advantage of the cellular defects caused by genomic instability. In particular, we identify and discuss five priority targets against genomic instability: (1) prevention of DNA damage; (2) enhancement of DNA repair; (3) targeting deficient DNA repair; (4) impairing centrosome clustering; and, (5) inhibition of telomerase activity. Moreover, we highlight vitamin D and B, selenium, carotenoids, PARP inhibitors, resveratrol, and isothiocyanates as priority approaches against genomic instability. The prioritized target sites and approaches were cross validated to identify potential synergistic effects on a number of important areas of cancer biology.

A multi-targeted approach to suppress tumor-promoting inflammation

Cancers harbor significant genetic heterogeneity and patterns of relapse following many therapies are due to evolved resistance to treatment. While efforts have been made to combine targeted therapies, significant levels of toxicity have stymied efforts to effectively treat cancer with multi-drug combinations using currently approved therapeutics. We discuss the relationship between tumor-promoting inflammation and cancer as part of a larger effort to develop a broad-spectrum therapeutic approach aimed at a wide range of targets to address this heterogeneity. Specifically, macrophage migration inhibitory factor, cyclooxygenase-2, transcription factor nuclear factor-κB, tumor necrosis factor alpha, inducible nitric oxide synthase, protein kinase B, and CXC chemokines are reviewed as important antiinflammatory targets while curcumin, resveratrol, epigallocatechin gallate, genistein, lycopene, and anthocyanins are reviewed as low-cost, low toxicity means by which these targets might all be reached simultaneously. Future translational work will need to assess the resulting synergies of rationally designed antiinflammatory mixtures (employing low-toxicity constituents), and then combine this with similar approaches targeting the most important pathways across the range of cancer hallmark phenotypes.

Effect of Carotene and Lycopene on the Risk of Prostate Cancer: A Systematic Review and Dose-Response Meta-Analysis of Observational Studies

Background

Many epidemiologic studies have investigated the association between carotenoids intake and risk of Prostate cancer (PCa). However, results have been inconclusive.

Methods

We conducted a systematic review and dose-response meta-analysis of dietary intake or blood concentrations of carotenoids in relation to PCa risk. We summarized the data from 34 eligible studies (10 cohort, 11 nested case-control and 13 case-control studies) and estimated summary Risk Ratios (RRs) and 95% confidence intervals (CIs) using random-effects models.

Results

Neither dietary β-carotene intake nor its blood levels was associated with reduced PCa risk. Dietary α-carotene intake and lycopene consumption (both dietary intake and its blood levels) were all associated with reduced risk of PCa (RR for dietary α-carotene intake: 0.87, 95%CI: 0.76–0.99; RR for dietary lycopene intake: 0.86, 95%CI: 0.75–0.98; RR for blood lycopene levels: 0.81, 95%CI: 0.69–0.96). However, neither blood α-carotene levels nor blood lycopene levels could reduce the risk of advanced PCa. Dose-response analysis indicated that risk of PCa was reduced by 2% per 0.2mg/day (95%CI: 0.96–0.99) increment of dietary α-carotene intake or 3% per 1mg/day (95%CI: 0.94–0.99) increment of dietary lycopene intake.

Conclusions

α-carotene and lycopene, but not β-carotene, were inversely associated with the risk of PCa. However, both α-carotene and lycopene could not lower the risk of advanced PCa.

In vitro steatosis hepatic cell model to compare the lipid-lowering effects of pomegranate peel polyphenols with several other plant polyphenols as well as its related cholesterol efflux mechanisms

This study was aimed to compare the relative activities of the purified pomegranate peels polyphenols (PPPs) with some other plant polyphenols including punicalagin, ellagic acid, gallic acid, phlorizin, and epigallocatechin gallate (EGCG) on the lipid metabolism regulation, and the cholesterol efflux mechanisms of PPPs and punicalagin were also investigated. In this paper, a convenient and accurate in vitro HL7702 steatosis hepatic cell model was applied to evaluate the lipid-lowering effects of the tested polyphenols. The results showed that PPPs possessed the strongest lipid-lowering effects. Prevention group (treated with polyphenols when establishing of steatosis model) was more effective than treatment group (treated with polyphenols after establishment of steatosis model). Punicalagin displayed the strongest lipid-lowering effects among all the tested components of pomegranate peel polyphenols. Moreover, PPPs and punicalagin (10, 20, 40 μg/mL) significantly increased the mRNA expression of LXRα (Liver X receptor alpha) and its target genes-ABCA1 (ATP-binding cassette transporter A1) in a dose-dependent manner in HL7702 steatosis hepatic cells. The high mRNA expression of LXRα and ABCA1, next to lovastatin, was observed in cells treated with 40 μg/mL of PPPs. These in vitro findings suggested that PPPs might have great potential in the clinic treatment of hyperlipemia.

Mitofusin 2 decreases intracellular lipids in macrophages by regulating peroxisome proliferator-activated receptor-γ

Mitofusin 2 (Mfn2) inhibits atherosclerotic plaque formation, but the underlying mechanism remains elusive. This study aims to reveal how Mfn2 functions in the atherosclerosis. Mfn2 expression was found to be significantly reduced in arterial atherosclerotic lesions of both mice and human compared with healthy counterparts. Here, we observed that Mfn2 increased cellular cholesterol transporter expression in macrophages by upregulating peroxisome proliferator-activated receptor-γ, an effect achieved at least partially by inhibiting extracellular signal-regulated kinase1/2 (ERK1/2) and p38 mitogen-activated protein kinases (MAPKs) pathway. These findings provide insights into potential mechanisms of Mfn2-mediated alterations in cholesterol transporter expression, which may have significant implications for the treatment of atherosclerotic heart disease.

Multiple molecular and cellular mechanisms of action of lycopene in cancer inhibition

Epidemiological studies suggest that including fruits, vegetables, and whole grains in regular dietary intake might prevent and reverse cellular carcinogenesis, reducing the incidence of primary tumours. Bioactive components present in food can simultaneously modulate more than one carcinogenic process, including cancer metabolism, hormonal balance, transcriptional activity, cell-cycle control, apoptosis, inflammation, angiogenesis and metastasis. Some studies have shown an inverse correlation between a diet rich in fruits, vegetables, and carotenoids and a low incidence of different types of cancer. Lycopene, the predominant carotenoid found in tomatoes, exhibits a high antioxidant capacity and has been shown to prevent cancer, as evidenced by clinical trials and studies in cell culture and animal models. In vitro studies have shown that lycopene treatment can selectively arrest cell growth and induce apoptosis in cancer cells without affecting normal cells. In vivo studies have revealed that lycopene treatment inhibits tumour growth in the liver, lung, prostate, breast, and colon. Clinical studies have shown that lycopene protects against prostate cancer. One of the main challenges in cancer prevention is the integration of new molecular findings into clinical practice. Thus, the identification of molecular biomarkers associated with lycopene levels is essential for improving our understanding of the mechanisms underlying its antineoplastic activity.

The potential role of lycopene for the prevention and therapy of prostate cancer: from molecular mechanisms to clinical evidence

Lycopene is a phytochemical that belongs to a group of pigments known as carotenoids. It is red, lipophilic and naturally occurring in many fruits and vegetables, with tomatoes and tomato-based products containing the highest concentrations of bioavailable lycopene. Several epidemiological studies have linked increased lycopene consumption with decreased prostate cancer risk. These findings are supported by in vitro and in vivo experiments showing that lycopene not only enhances the antioxidant response of prostate cells, but that it is even able to inhibit proliferation, induce apoptosis and decrease the metastatic capacity of prostate cancer cells. However, there is still no clearly proven clinical evidence supporting the use of lycopene in the prevention or treatment of prostate cancer, due to the only limited number of published randomized clinical trials and the varying quality of existing studies. The scope of this article is to discuss the potential impact of lycopene on prostate cancer by giving an overview about its molecular mechanisms and clinical effects.

Lycopene modulates growth and survival associated genes in prostate cancer

Lycopene is a fat soluble red-orange carotenoid pigment present in tomato that reduces the risk for prostate cancer, a common malignancy among men. However, the mechanism by which lycopene attenuates prostate cancer is not fully defined. In this study we examined the effect of lycopene on proliferation, survival, and biomarker gene expression in prostate cancer (PC-3) cells in culture. WST-1 assay showed that lycopene induces a biphasic effect on PC-3 cells with a modest increase in proliferation at 1-5 μM, no change at 10-25 μM and a decrease at 50-100 μM doses in culture. Interestingly, combination treatment with lycopene induced anti-proliferative effect of Temozolomide on PC-3 cells. Lycopene also augmented the anti-proliferative effect of peroxisome proliferator-activated receptor gamma (PPARγ) agonists, but not Doxorubicin or Taxol, in prostate cancer. Flow cytometry analyses showed that lycopene, in combination with chemotherapeutic agents and PPARγ agonists, induced modest cell cycle arrest with significant increase in cell death by apoptosis and necrosis on prostate cancer. Gene array and quantitative reverse transcription polymerase chain reaction analyses showed that lycopene alters the expression of growth and apoptosis associated biomarkers in PC-3 cells. These findings highlight that lycopene attenuates prostate cancer by modulating the expression of growth and survival associated genes.