Brassica-derived isothiocyanates as anticancer therapeutic agents and their nanodelivery.

The isothiocyanates (ITCs) derived from the precursor glucosinolate molecules present in Brassica vegetables are bioactive organo-sulfur compounds with numerous pharmacologically important properties such as antioxidant, antiinflammatory, antimicrobial, and anticancer. Over the years, ITCs have been the focus of several research investigations associated with cancer treatment. Due to their potent chemo-preventive action, ITCs have been considered to be promising therapeutics for cancer therapy in place of the already existing conventional anticancer drugs. However, their wide spread use at the clinical stage is greatly restricted due to several factors such as low solubility in an aqueous medium, low bioavailability, low stability, and hormetic effect. To overcome these hindrances, nanotechnology can be exploited to develop nano-scale delivery systems that have the potential to enhance stability, and bioavailability and minimize the hermetic effect of ITCs.

An Update on Potential Molecular Biomarkers of Dietary Phytochemicals Targeting Lung Cancer Interception and Prevention.

Since ancient times, dietary phytochemicals are known for their medicinal properties. They are broadly classified into polyphenols, terpenoids, alkaloids, phytosterols, and organosulfur compounds. Currently, there is considerable interest in their potential health effects against various diseases, including lung cancer. Lung cancer is the leading cause of cancer deaths with an average of five-year survival rate of lung cancer patients limited to just 14%. Identifying potential early molecular biomarkers of pre-malignant lung cancer cells may provide a strong basis to develop early cancer detection and interception methods. In this review, we will discuss molecular changes, including genetic alterations, inflammation, signal transduction pathways, redox imbalance, epigenetic and proteomic signatures associated with initiation and progression of lung carcinoma. We will also highlight molecular targets of phytochemicals during lung cancer development. These targets mainly consist of cellular signaling pathways, epigenetic regulators and metabolic reprogramming. With growing interest in natural products research, translation of these compounds into new cancer prevention approaches to medical care will be urgently needed. In this context, we will also discuss the overall pharmacokinetic challenges of phytochemicals in translating to humans. Lastly, we will discuss clinical trials of phytochemicals in lung cancer patients.

The anticarcinogenic effect of eugenol on lung cancer induced by diethylnitrosamine/2-acetylaminofluorene in Wistar rats: insight on the mechanisms of action.

This study was designed to assess the ameliorative effects of eugenol and to propose the possible mechanisms of action of eugenol in diethylnitrosamine (DENA)/acetylaminofluorene (AAF)-caused lung cancer in Wistar rats. To induce lung cancer, DENA at a dose of 150 mg/kg body weight (b.wt) for 2 weeks were intraperitoneally injected once each week and AAF was administered orally at a dose of 20 mg/kg b.wt. four times each week for the next 3 weeks. DENA/AAF-administered rats were orally supplemented with eugenol at a dose of 20 mg/kg b.wt administered once a day until 17 weeks starting from the 1st week of DENA administration. Lung histological lesions, including sheets of tumor cells, micropapillary adenocarcinoma, and apoptotic cells, resulting from the DENA/AAF dosage, were ameliorated by eugenol treatment. However, a significant drop in the levels of LPO in the lungs and a remarkable rise in GSH content and GPx and SOD activities were observed in DENA/AAF-administered rats treated with eugenol compared with those in DENA/AAF-administered controls. Moreover, in DENA/AAF-administered rats, eugenol supplementation significantly reduced TNF-α and IL-1ß levels and mRNA expression levels of NF-κB, NF-κB p65, and MCP-1 but significantly elevated the level of Nrf2. Furthermore, the DENA/AAF-administered rats treated with eugenol exhibited a significant downregulation of Bcl-2 expression levels in addition to a significant upregulation in P53 and Bax expression levels. Otherwise, the administration of DENA/AAF elevated the protein expression level of Ki-67, and this elevation was reversed by eugenol treatment. In conclusion, eugenol has effective antioxidant, anti-inflammatory, proapoptotic, and antiproliferative properties against lung cancer.

The Role of Phytochemicals in Cancer Prevention: A Review with Emphasis on Baicalein, Fisetin, and Biochanin A.

Cancer is a disease in which repeated rounds of mutations cause uncontrolled growth of cells, which prospers at the expense of their neighbor cells and then eventually leads to the destruction of the whole cellular community. Chemopreventive drugs either prevent DNA damage, which results in malignancy, or they stop or reverse the division of premalignant cells with DNA damage, which inhibits the growth of cancer. There is an obvious need for an alternate strategy given the ongoing rise in cancer incidence, the ineffectiveness of traditional chemotherapies to control cancer, and the excessive toxicity of chemotherapies. From antiquity to date, the saga of the usage of plants as medicine has been the mainstay among people worldwide. In recent years, extensive studies have been conducted on medicinal plants, spices, and nutraceuticals, as these have gained much popularity in reducing the risk of several cancer types in humans. Extensive studies on cell culture systems and animal models have demonstrated that various medicinal plants and nutraceuticals from various natural resources and their products, such as major polyphenolic constituents, flavones, flavonoids, antioxidants, etc, provide considerable protection against many cancer types. As shown in the literatures, the major aim of studies conducted is to develop preventive/therapeutic agents which can induce apoptosis in cancer cells without affecting normal cells. Projects are going on worldwide to find better ways to eradicate the disease. The study of phytomedicines has shed new light on this topic as research to date has proven that they have antiproliferative and apoptotic capabilities that will aid in the development of novel cancer prevention options. Dietary substances, such as Baicalein, Fisetin, and Biochanin A have shown that they have an inhibitory effect on cancer cells, suggesting that they may work as chemopreventive agents. This review discusses the chemopreventive and anticancer mechanisms of such reported natural compounds.

The Potential Chemopreventive Effect of Andrographis paniculata on 1,2-Dimethylhydrazine and High-Fat-Diet-Induced Colorectal Cancer in Sprague Dawley Rats.

Colorectal cancer (CRC) is responsible for a notable rise in the overall mortality rate. Obesity is found to be one of the main factors behind CRC development. Andrographis paniculata is a herbaceous plant famous for its medicinal properties, particularly in Southeast Asia for its anti-cancer properties. This study examines the chemopreventive impact of A. paniculata ethanolic extract (APEE) against a high-fat diet and 1,2-dimethylhydrazine-induced colon cancer in Sprague Dawley rats. Sprague Dawley rats were administered 1,2-dimethylhydrazine (40 mg/kg, i.p. once a week for 10 weeks) and a high-fat diet (HFD) for 20 weeks to induce colorectal cancer. APEE was administered at 125 mg/kg, 250 mg/kg, and 500 mg/kg for 20 weeks. At the end of the experiment, blood serum and organs were collected. DMH/HFD-induced rats had abnormal crypts and more aberrant crypt foci (ACF). APEE at a dose of 500 mg/kg improved the dysplastic state of the colon tissue and caused a 32% reduction in the total ACF. HFD increased adipocyte cell size, while 500 mg/kg APEE reduced it. HFD and DMH/HFD rats had elevated serum insulin and leptin levels. Moreover, UHPLC-QTOF-MS analysis revealed that APEE was rich in anti-cancer phytochemicals. This finding suggests that APEE has anti-cancer potential against HFD/DMH-induced CRC and anti-adipogenic and anti-obesity properties.

A mechanistic updated overview on lycopene as potential anticancer agent.

The potent relation between lycopene intake and reduced incidence of a variety of cancers has an increasing interest. This comprehensive review aims to highlight the in vivo and in vitro research evaluating the anticancer mechanisms of lycopene by underlining the experiment conditions. In addition to these, the general characterization of lycopene has been explained. A collection of relevant scientific pharmacological articles from the following databases PubMed/MedLine, Web of Science, Scopus, TRIP database, and Google Scholar on the mechanisms of anticancer molecular action and cellular effects of lycopene in various types of tumors was performed. The anticancer potential of lycopene has been described by various in vitro cells, animal studies, and some clinical trials. It has been revealed that the anticancer potential of lycopene is mainly due to its powerful singlet-oxygen quencher characteristics, simulation of detoxifying/antioxidant enzymes production, initiation of apoptosis, inhibition of cell proliferation and cell cycle progression as well as modulations of gap junctional communication, the growth factors, and signal transduction pathways. It has been highlighted that the anticancer properties of lycopene are primarily linked to factors including; dose, presence of drug delivery systems, type of cancer, tumor size, and treatment time.

Lycopene as a Potential Bioactive Compound: Chemistry, Extraction, and Anticancer Prospective.

Lycopene, a potential bioactive agent, is a non-pro-vitamin A carotenoid recognized as a potent antioxidant. It is extracted from plants like tomatoes, watermelons, red carrots and papayas and has remarkable health benefits. A significant amount of research has been assisted to date to establish the anticancer activity of lycopene. Our review enhances information about the promising anticancer potential of this compound. The biological activity of lycopene has been described in several studies in regard to pancreatic, breast, prostate, liver, gastric, ovarian, kidney, skin, intestine, brain and spinal cord cancers. Lycopene resists cancer by inhibition of apoptosis, induction of cell proliferation, cell invasion, cell cycle development, metastasis and angiogenesis. The mechanisms of anticancer action of lycopene are attributed to the management of certain signal transduction pathways, such as modulation of insulin-like growth factors system, PI3K/Akt pathway, modification of important gene expression, inhibit the activity of sex steroid hormones, and the conversation of mitochondrial behavior. Hence, this review focuses on current knowledge of sources, extraction techniques, and chemistry of lycopene, as well as the prospective mechanisms of action related with its anticancer activity. Also, it summarizes the background information about lycopene and the most current research with consideration to its aspect in treating several types of cancer together with future directions.

Korean practice guidelines for gastric cancer 2022: an evidence-based, multidisciplinary approach

Gastric cancer is one of the most common cancers in Korea and the world. Since 2004, this is the 4th gastric cancer guideline published in Korea which is the revised version of previous evidence-based approach in 2018. Current guideline is a collaborative work of the interdisciplinary working group including experts in the field of gastric surgery, gastroenterology, endoscopy, medical oncology, abdominal radiology, pathology, nuclear medicine, radiation oncology and guideline development methodology. Total of 33 key questions were updated or proposed after a collaborative review by the working group and 40 statements were developed according to the systematic review using the MEDLINE, Embase, Cochrane Library and KoreaMed database. The level of evidence and the grading of recommendations were categorized according to the Grading of Recommendations, Assessment, Development and Evaluation proposition. Evidence level, benefit, harm, and clinical applicability was considered as the significant factors for recommendation. The working group reviewed recommendations and discussed for consensus. In the earlier part, general consideration discusses screening, diagnosis and staging of endoscopy, pathology, radiology, and nuclear medicine. Flowchart is depicted with statements which is supported by meta-analysis and references. Since clinical trial and systematic review was not suitable for postoperative oncologic and nutritional follow-up, working group agreed to conduct a nationwide survey investigating the clinical practice of all tertiary or general hospitals in Korea. The purpose of this survey was to provide baseline information on follow up. Herein we present a multidisciplinary-evidence based gastric cancer guideline.

Indole-3-carbinol (I3C) as Leukemia Therapeutic Agents: Review.

Leukemia or blood cancer was initially discovered in 1845 and this malignancy was reported in patients who had an amplified number of blood cells, in particular, White Blood Cells (WBC), due to this disease. The event of leukemia was further identified as a malignant hematopoietic disorder due to both uncontrolled and unlimited proliferation in combination with a lack of differentiation of the leukemic stem cells. Furthermore, 75 to 80% of the global population use herbal remedies as primary therapy, mainly because of their better efficiency and satisfaction, which elevate the human body symmetry with the minimum unwanted adverse effects. For the control of cancer, plant products, and fruits have been considered promising tools and are being consumed for centuries. Several plant extracts are also being used for the therapy and prevention of different types of known cancers. Indole-3-carbinol (I3C) is a natural material obtained from Brassica diversity of vegetables and has been reported to serve as a promising cancer preventative agent. In the present review, the authors mainly tried to focus on and emphasize I3C applications in leukemia treatment.

Anticarcinogenic Effects of Isothiocyanates on Hepatocellular Carcinoma.

Hepatocellular carcinoma (HCC) is the most common type of primary liver cancer, accounting for about 90% of cases. Sorafenib, lenvatinib, and the combination of atezolizumab and bevacizumab are considered first-line treatments for advanced HCC. However, clinical application of these drugs has also caused some adverse reactions such as hypertension, elevated aspartate aminotransferases, and proteinuria. At present, natural products and their derivatives have drawn more and more attention due to less side effects as cancer treatments. Isothiocyanates (ITCs) are one type of hydrolysis products from glucosinolates (GLSs), secondary plant metabolites found exclusively in cruciferous vegetables. Accumulating evidence from encouraging in vitro and in vivo animal models has demonstrated that ITCs have multiple biological activities, especially their potentially health-promoting activities (antibacterial, antioxidant, and anticarcinogenic effects). In this review, we aim to comprehensively summarize the chemopreventive, anticancer, and chemosensitizative effects of ITCs on HCC, and explain the underlying molecular mechanisms.

[The National Consensus statement on the management of adult patients with non-alcoholic fatty liver disease and main comorbidities].

The National Consensus was prepared with the participation of the National Medical Association for the Study of the Multimorbidity, Russian Scientific Liver Society, Russian Association of Endocrinologists, Russian Association of Gerontologists and Geriatricians, National Society for Preventive Cardiology, Professional Foundation for the Promotion of Medicine Fund PROFMEDFORUM. The aim of the multidisciplinary consensus is a detailed analysis of the course of non-alcoholic fatty liver disease (NAFLD) and the main associated conditions. The definition of NAFLD is given, its prevalence is described, methods for diagnosing its components such as steatosis, inflammation and fibrosis are described. The association of NAFLD with a number of cardio-metabolic diseases (arterial hypertension, atherosclerosis, thrombotic complications, type 2 diabetes mellitus, obesity, dyslipidemia, etc.), chronic kidney disease and the risk of developing hepatocellular cancer were analyzed. The review of non-drug methods of treatment of NAFLD and modern opportunities of pharmacotherapy are presented. The possibilities of new molecules in the treatment of NAFLD are considered: agonists of nuclear receptors, antagonists of pro-inflammatory molecules, etc. The positive properties and disadvantages of currently used drugs (vitamin E, thiazolidinediones, etc.) are described. Special attention is paid to the multi-target ursodeoxycholic acid molecule in the complex treatment of NAFLD as a multifactorial disease. Its anti-inflammatory, anti-oxidant and cytoprotective properties, the ability to reduce steatosis an independent risk factor for the development of cardiovascular pathology, reduce inflammation and hepatic fibrosis through the modulation of autophagy are considered. The ability of ursodeoxycholic acid to influence glucose and lipid homeostasis and to have an anticarcinogenic effect has been demonstrated. The Consensus statement has advanced provisions for practitioners to optimize the diagnosis and treatment of NAFLD and related common pathogenetic links of cardio-metabolic diseases.

Renal cell carcinoma management: A step to nano-chemoprevention.

Renal cell carcinoma (RCC) is one of the most common kidney cancers, responsible for nearly 90 % of all renal malignancies. Despite the availability of many treatment strategies, RCC still remains to be an incurable disease due to its resistivity towards conventional therapies. Nanotechnology is an emerging field of science that offers newer possibilities in therapeutics including cancer medicine, specifically by targeted delivery of anticancer drugs. Several phytochemicals are known for their anti-cancer properties and have been regarded as chemopreventive agents. However, the hydrophobic nature of many phytochemicals decreases its bioavailability and distribution, thus showing limited therapeutic effect. Application of nanotechnology to enhance chemoprevention is an effective strategy to increase the bioavailability of phytochemicals and thereby its therapeutic efficacy. The present review focuses on the utility of nanotechnology in RCC treatment and chemopreventive agents of RCC. We have also visualized the future prospects of nanomolecules in the prevention and cure of RCC.

Polyphenols as Lung Cancer Chemopreventive Agents by Targeting microRNAs.

Lung cancer is the second leading cause of cancer-related death worldwide. In recent decades, investigators have found that microRNAs, a group of non-coding RNAs, are abnormally expressed in lung cancer, and play important roles in the initiation and progression of lung cancer. These microRNAs have been used as biomarkers and potential therapeutic targets of lung cancer. Polyphenols are natural and bioactive chemicals that are synthesized by plants, and have promising anticancer effects against several kinds of cancer, including lung cancer. Recent studies identified that polyphenols exert their anticancer effects by regulating the expression levels of microRNAs in lung cancer. Targeting microRNAs using polyphenols may provide a novel strategy for the prevention and treatment of lung cancer. In this review, we reviewed the effects of polyphenols on oncogenic and tumor-suppressive microRNAs in lung cancer. We also reviewed and discussed the potential clinical application of polyphenol-regulated microRNAs in lung cancer treatment.

The Association Between the Risk of Breast Cancer and Epigallocatechin- 3-Gallate Intake: A Literature Review of a Potential Chemopreventive Agent.

According to the latest epidemiological data, breast cancer has recently been the most frequently diagnosed malignancy. To date, a body of evidence has established the involvement of multiple - and frequently interrelated - genetic and environmental factors in the pathogenesis of the disease. Emerging research on cancer prevention has highlighted the deterrence potential of interventions targeting environmental risk factors, particularly diet. In this aspect, the current review reveals the latest scientific results regarding epigallocatechin-3-gallate (EGCG) - a catechin most commonly found in green tea, as a potential chemopreventive dietary agent against breast cancer. in vitro studies on EGCG have demonstrated its effect on cell cycle progression and its potential to suppress several intracellular signaling pathways involved in breast cancer pathogenesis. In addition, EGCG possesses specific apoptosis-inducing characteristics that seem to enhance its role as a regulator of cell survival. Preclinical data seem to support using EGCG as an effective adjunct to EGFR-targeting treatments. The authors' appraisal of the literature suggests that although preclinical evidence has documented the anticarcinogenic features of EGCG, limited large-scale epidemiological studies are investigating the consumption of EGCG - containing nutrients in the prevention and management of breast cancer risk. This literature review aims to liaise between preclinical and epidemiological research, surveying the existing evidence and unraveling relevant knowledge gaps.

Inhibition of Integrin αVß3 Signaling Improves the Antineoplastic Effect of Bexarotene in Cutaneous T-Cell Lymphoma.

Bexarotene is a specific retinoid X receptor agonist that has been used for the treatment of cutaneous T-cell lymphoma (CTCL). Because bexarotene causes hypothyroidism, it requires the administration of levothyroxine. However, levothyroxine, in addition to its ubiquitous nuclear receptors, can activate the αVß3 integrin that is overexpressed in CTCL, potentially interfering the antineoplastic effect of bexarotene. We thus investigated the biological effect of levothyroxine in relation to bexarotene treatment. Although in isolated CTCL cells levothyroxine decreased, in an αVß3-dependent manner, the antineoplastic effect of bexarotene, levothyroxine supplementation in preclinical models was necessary to avoid suppression of lymphoma immunity. Accordingly, selective genetic and pharmacologic inhibition of integrin αVß3 improved the antineoplastic effect of bexarotene plus levothyroxine replacement while maintaining lymphoma immunity. Our results provide a mechanistic rationale for clinical testing of integrin αVß3 inhibitors as part of CTCL regimens based on bexarotene administration. TEASER: Inhibiting αVß3 integrin improves the antineoplastic effect of bexarotene while maintaining lymphoma immunity.

Experimental carcinogenesis with 7, 12-dimethylbenz(a)anthrazene (DMBA) and its inhibition with isothi-ocyanates / Carcinogénesis experimental con 7, 12-dimetilbenzantraceno (DMBA) y su inhibición con isitiocianatos

Introduction: DMBA is a chemical carcinogen that induces carcinomas within a few weeks of its application. We developed an experimental model of carcinogenesis induced by DMBA dissolved in 0,5% paraffin oil (DMBA-PO), verifying the inhibitory effect of the carcinogenicity of phenyl isothiocyanate (PhITC), phenethyl (PhnITC) and benzyl isothiocyanate (BITC). Material and Methods: For this, 88 hamsters were distributed into three groups: one exposed to DMBA-PO (Group 1, n=12), three subgroups (n=12) exposed to PhITC, PhnITC, BITC and DMBA-PO (Group 2, n=36) and four control subgroups (n=10) that were not exposed to the carcinogen in which PO (paraffin oil) and isothiocyanates were applied (Group 3, n=40). Results: The experiment had a duration of 20 weeks, at the end of which the inhibitory effect was established by comparing the lesions developed in the groups that received isothiocyanates with the group that was only treated with DMBA-PO. The carcinogenic effect of DMBA-PO is 100% (35 carcinomas) and the inhibitory effect was 0, whereas in the presence of isothiocyanates the carcinogenic effect decreases, with an inhibitory effect of 86% for BITC (5 carcinomas) and 74% for PhITC (9 carcinomas). Conclusion: The inhibitory effect for PhnITC is 80% in relation to invasive OSCC (1 carcinoma).

Introducción: El DMBA es un carcinógeno químico que induce carcinomas a las pocas semanas de su aplicación. Desarrollamos un modelo experimental de carcinogénesis inducida por DMBA disuelto en aceite de parafina al 0,5% (DMBA-Ap) comprobando el efecto inhibidor de la carcinogénesis de los isotiocianatos fenil (PhITC), fenetil (PhnITC) y bencil isotiocianato (BITC). Material y Métodos: Para ello, se distribuyeron 88 hámsteres en 3 grupos: uno expuesto al DMBA-Ap (Grupo 1, n=12), tres subgrupos (n=12) expuestos a PhITC, PhnITC, BITC y DMBA-Ap (Grupo 2, n=36) y cuatro subgrupos controles (n=10), no expuestos al carcinógeno en el que se aplicaron Ap e isotiocianatos (Grupo 3, n=40). Resultados:El experimento tuvo una duración de 20 semanas, al final de la cual se establece de forma comparativa el efecto inhibidor comparando las lesiones desarrolladas en los grupos que recibieron isotiocianatos con respecto al grupo tratado sólo con DMBA-Ap. El efecto carcinógeno del DMBA-Ap es del 100% (35 carcinomas) y el efecto inhibidor 0, mientras que en presencia de isotiocianatos el efecto carcinógeno disminuye, con un efecto inhibidor del 86% para BITC (5 carcinomas) y del 74% para el PhITC (9 carcinomas). Conclusión:El efecto inhibidor del PhnITC es del 80% en relación con el COCE invasivo (1 carcinoma).

Plasma Metabolomics Analysis of Aspirin Treatment and Risk of Colorectal Adenomas.

Despite substantial observational and experimental evidence that aspirin use can provide protection against the development of colorectal neoplasia, our understanding of the molecular mechanisms involved is inadequate and limits our ability to use this drug effectively and safely for chemoprevention. We employed an untargeted plasma metabolomics approach using liquid chromatography with high-resolution mass spectroscopy to explore novel metabolites that may contribute to the chemopreventive effects of aspirin. Associations between levels of metabolic features in plasma and aspirin treatment were investigated among 523 participants in a randomized placebo-controlled clinical trial of two doses of aspirin (81 or 325 mg/day) and were linked to risk of colorectal adenoma occurrence over 3 years of follow-up. Metabolic pathways that were altered with aspirin treatment included linoleate and glycerophospholipid metabolism for the 81-mg dose and carnitine shuttle for both doses. Metabolites whose levels increased with 81 mg/day aspirin treatment and were also associated with decreased risk of adenomas during follow-up included certain forms of lysophosphatidylcholine and lysophosphatidylethanolamine as well as trihydroxyoctadecenoic acid, which is a derivative of linoleic acid and is upstream of cyclooxygenase inhibition by aspirin in the linoleate and arachidonic acid metabolism pathways. In conclusion, our findings regarding lysophospholipids and metabolites in the linoleate metabolism pathway may provide novel insights into the chemopreventive effects of aspirin in the colorectum, although they should be considered hypothesis-generating at this time. PREVENTION RELEVANCE: This research used metabolomics, an innovative discovery-based approach, to identify molecular changes in human blood that may help to explain how aspirin use reduces the risk of colorectal neoplasia in some individuals. Ultimately, this work could have important implications for optimizing aspirin use in the prevention of colorectal cancer.

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.

Tomatoes, Lycopene, and Prostate Cancer: What Have We Learned from Experimental Models?

Human epidemiology suggests a protective effect of tomatoes or tomato phytochemicals, such as lycopene, on prostate cancer risk. However, human epidemiology alone cannot reveal causal relations. Laboratory animal models of prostate cancer provide opportunities to investigate hypotheses regarding dietary components in precisely controlled, experimental systems, contributing to our understanding of diet and cancer risk relations. We review the published studies evaluating the impact of tomatoes and/or lycopene in preclinical models of prostate carcinogenesis and tumorigenesis. The feeding of tomatoes or tomato components demonstrates anti-prostate cancer activity in both transplantable xenograft models of tumorigenesis and models of chemically- and genetically-driven carcinogenesis. Feeding pure lycopene shows anticancer activity in most studies, although outcomes vary by model system, suggesting that the impact of pure lycopene can depend on dose, duration, and specific carcinogenic processes represented in different models. Nonetheless, studies with the transgenic adenocarcinoma of the mouse prostate (TRAMP) model of carcinogenesis typically demonstrate similar bioactivity to that of tomato feeding. In general, interventions that commence earlier in carcinogenesis and are sustained tend to be more efficacious. Accumulated data suggest that lycopene is one, but perhaps not the only, anticancer bioactive compound in tomatoes. Although it is clear that tomatoes and lycopene have anti-prostate cancer activity in rodent models, major knowledge gaps remain in understanding dose-response relations and molecular mechanisms of action. Published and future findings from rodent studies can provide guidance for translational scientists to design and execute informative human clinical trials of prostate cancer prevention or in support of therapy.