Breast Cancer Prevention-Is there a Future for Sulforaphane and Its Analogs?

Antitumor and antimetastatic effects of dietary sulforaphane in a triple-negative breast cancer models

Triple-negative breast cancer (TNBC) represents aggressive phenotype with limited treatment options due to the lack of drug targets. Natural compounds are extensively studied regarding their potential to alter the efficacy of cancer treatment Among them sulforaphane - an isothiocyanate of natural origin, was shown to be a hormetic compound, that may exert divergent effects: cytoprotective or cytotoxic depending on its concentrations. Thus, the aim of this study was to determine the effect of its low, dietary concentrations on the proliferation and migration of the TNBC cells in the in vivo and in vitro 2D and 3D model. Results of the in vivo experiment showed up to 31% tumor growth inhibition after sulforaphane treatment associated with lowered proliferating potential of cancer cells, reduced areas of necrosis, and changed immune cell type infiltration, showing less malignant type of tumor in contrast to the non-treated group. Also, the study revealed that sulforaphane decreased the number of lung metastases. The in vitro study confirmed that SFN inhibited cell migration, but only in cells derived from 3D spheroids, not from 2D in vitro cultures. The results show a specific role of sulforaphane in the case of cells released from the TNBC primary tumor and its environment.

Synergic Role of Dietary Bioactive Compounds in Breast Cancer Chemoprevention and Combination Therapies

Breast cancer is the most common tumor in women. Chemotherapy is the gold standard for cancer treatment; however, severe side effects and tumor resistance are the major obstacles to chemotherapy success. Numerous dietary components and phytochemicals have been found to inhibit the molecular and signaling pathways associated with different stages of breast cancer development. In particular, this review is focused on the antitumor effects of PUFAs, dietary enzymes, and glucosinolates against breast cancer. The major databases were consulted to search in vitro and preclinical studies; only those with solid scientific evidence and reporting protective effects on breast cancer treatment were included. A consistent number of studies highlighted that dietary components and phytochemicals can have remarkable therapeutic effects as single agents or in combination with other anticancer agents, administered at different concentrations and via different routes of administration. These provide a natural strategy for chemoprevention, reduce the risk of breast cancer recurrence, impair cell proliferation and viability, and induce apoptosis. Some of these bioactive compounds of dietary origin, however, show poor solubility and low bioavailability; hence, encapsulation in nanoformulations are promising tools able to increase clinical efficiency.

Bioactive sulforaphane from cruciferous vegetables: advances in biosynthesis, metabolism, bioavailability, delivery, health benefits, and applications

Chronic inflammation-induced diseases (CID) are the dominant cause of death worldwide, contributing to over half of all global deaths. Sulforaphane (SFN) derived from cruciferous vegetables has been extensively studied for its multiple functional benefits in alleviating CID. This work comprehensively reviewed the biosynthesis, metabolism, bioavailability, delivery, health benefits, and applications of SFN and its potential mechanisms against CID (e.g., cancer, obesity, type 2 diabetes, et al.), and neurological disorders based on a decade of research. SFN exerts its biological functions through the hydrolysis of glucosinolates by gut microbiota, and exhibits rapid metabolism and excretion characteristics via metabolization of mercapturic acid pathway. Microencapsulation is an important way to improve the stability and targeted delivery of SFN. The health benefits of SNF against CID are attributed to the multiple regulatory mechanisms including modulating oxidative stress, inflammation, apoptosis, immune response, and intestinal homeostasis. The clinical applications of SFN and related formulations show promising potential; however, further exploration is required regarding the sources, dosages, toxicity profiles, and stability of SFN. Together, SFN is a natural product with great potential for development and application, which is crucial for the development of functional food and pharmaceutical industries.

Natural Products for Cancer Prevention and Interception: Preclinical and Clinical Studies and Funding Opportunities

Multiple agents derived from natural products (NPs) have been evaluated for cancer prevention and interception, either alone or in combination. The National Cancer Institute (NCI) is very interested in advancing research to identify additional agents that, alone or in combination, may prove useful in cancer prevention. Below, we provide an overview of NP studies in cancer prevention and interception, both individual agents and combination interventions. Given that findings from many preclinical studies evaluating individual agents have generally not been confirmed in human studies, our focus with individual NPs in this review is on studies involving humans, especially clinical trials. Fewer combination intervention studies have been conducted, so we have broadened our review to include preclinical studies. We conclude with how the Division of Cancer Prevention (DCP) within the NCI is providing funding to encourage the research community to propose natural product studies in cancer prevention and interception to advance the field.

Tailoring Potential Natural Compounds for the Treatment of Luminal Breast Cancer

Breast cancer (BC) is the most diagnosed cancer worldwide, mainly affecting the epithelial cells from the mammary glands. When it expresses the estrogen receptor (ER), the tumor is called luminal BC, which is eligible for endocrine therapy with hormone signaling blockade. Hormone therapy is essential for the survival of patients, but therapeutic resistance has been shown to be worrying, significantly compromising the prognosis. In this context, the need to explore new compounds emerges, especially compounds of plant origin, since they are biologically active and particularly promising. Natural products are being continuously screened for treating cancer due to their chemical diversity, reduced toxicity, lower side effects, and low price. This review summarizes natural compounds for the treatment of luminal BC, emphasizing the activities of these compounds in ER-positive cells. Moreover, their potential as an alternative to endocrine resistance is explored, opening new opportunities for the design of optimized therapies.

Anticancer activity of broccoli, its organosulfur and polyphenolic compounds

The use of natural bioactive constituents from various food sources for anticancer purposes has become increasingly popular worldwide. Broccoli (Brassica oleracea var. italica) is on the top of the consumed vegetables by the masses. Its raw matrix contains a plethora of phytochemicals, such as glucosinolates and phenolic compounds, along with rich amounts of vitamins, and minerals. Consumption of broccoli-derived phytochemicals provides strong antioxidant effects, particularly due to its sulforaphane content, while modulating numerous molecules involved in cell cycle regulation, control of apoptosis, and tuning enzyme activity. Thus, the inclusion of broccoli in the daily diet lowers the susceptibility to developing cancers. Numerous studies have underlined the undisputable role of broccoli in the diet as a chemopreventive raw food, owing to the content in sulforaphane, an isothiocyanate produced as a result of hydrolysis of precursor glucosinolates called glucoraphanin. This review will provide evidence supporting the specific role of fresh florets and sprouts of broccoli and its key bioactive constituents in the prevention and treatment of different cancers; a number of studies carried out in the in vitro and in vivo conditions as well as clinical trials were analyzed.

Nutraceuticals as Potential Therapeutic Modulators in Immunometabolism

Nutraceuticals act as cellular and functional modulators, contributing to the homeostasis of physiological processes. In an inflammatory microenvironment, these functional foods can interact with the immune system by modulating or balancing the exacerbated proinflammatory response. In this process, immune cells, such as antigen-presenting cells (APCs), identify danger signals and, after interacting with T lymphocytes, induce a specific effector response. Moreover, this conditions their change of state with phenotypical and functional modifications from the resting state to the activated and effector state, supposing an increase in their energy requirements that affect their intracellular metabolism, with each immune cell showing a unique metabolic signature. Thus, nutraceuticals, such as polyphenols, vitamins, fatty acids, and sulforaphane, represent an active option to use therapeutically for health or the prevention of different pathologies, including obesity, metabolic syndrome, and diabetes. To regulate the inflammation associated with these pathologies, intervention in metabolic pathways through the modulation of metabolic energy with nutraceuticals is an attractive strategy that allows inducing important changes in cellular properties. Thus, we provide an overview of the link between metabolism, immune function, and nutraceuticals in chronic inflammatory processes associated with obesity and diabetes, paying particular attention to nutritional effects on APC and T cell immunometabolism, as well as the mechanisms required in the change in energetic pathways involved after their activation.

Molecular Mechanisms of Anti-Estrogen Therapy Resistance and Novel Targeted Therapies

Breast cancer (BC) is the most commonly diagnosed cancer in women, constituting one-third of all cancers in women, and it is the second leading cause of cancer-related deaths in the United States. Anti-estrogen therapies, such as selective estrogen receptor modulators, significantly improve survival in estrogen receptor-positive (ER+) BC patients, which represents about 70% of cases. However, about 60% of patients inevitably experience intrinsic or acquired resistance to anti-estrogen therapies, representing a major clinical problem that leads to relapse, metastasis, and patient deaths. The resistance mechanisms involve mutations of the direct targets of anti-estrogen therapies, compensatory survival pathways, as well as alterations in the expression of non-coding RNAs (e.g., microRNA) that regulate the activity of survival and signaling pathways. Although cyclin-dependent kinase 4/6 and phosphatidylinositol 3-kinase (PI3K)/AKT/mammalian target of rapamycin (mTOR) inhibitors have significantly improved survival, the efficacy of these therapies alone and in combination with anti-estrogen therapy for advanced ER+ BC, are not curative in advanced and metastatic disease. Therefore, understanding the molecular mechanisms causing treatment resistance is critical for developing highly effective therapies and improving patient survival. This review focuses on the key mechanisms that contribute to anti-estrogen therapy resistance and potential new treatment strategies alone and in combination with anti-estrogen drugs to improve the survival of BC patients.

Oxidative Stress and NRF2/KEAP1/ARE Pathway in Diabetic Kidney Disease (DKD): New Perspectives

Diabetes mellitus (DM) is one of the most debilitating chronic diseases worldwide, with increased prevalence and incidence. In addition to its macrovascular damage, through its microvascular complications, such as Diabetic Kidney Disease (DKD), DM further compounds the quality of life of these patients. Considering DKD is the main cause of end-stage renal disease (ESRD) in developed countries, extensive research is currently investigating the matrix of DKD pathophysiology. Hyperglycemia, inflammation and oxidative stress (OS) are the main mechanisms behind this disease. By generating pro-inflammatory factors (e.g., IL-1,6,18, TNF-α, TGF-β, NF-κB, MCP-1, VCAM-1, ICAM-1) and the activation of diverse pathways (e.g., PKC, ROCK, AGE/RAGE, JAK-STAT), they promote a pro-oxidant state with impairment of the antioxidant system (NRF2/KEAP1/ARE pathway) and, finally, alterations in the renal filtration unit. Hitherto, a wide spectrum of pre-clinical and clinical studies shows the beneficial use of NRF2-inducing strategies, such as NRF2 activators (e.g., Bardoxolone methyl, Curcumin, Sulforaphane and their analogues), and other natural compounds with antioxidant properties in DKD treatment. However, limitations regarding the lack of larger clinical trials, solubility or delivery hamper their implementation for clinical use. Therefore, in this review, we will discuss DKD mechanisms, especially oxidative stress (OS) and NRF2/KEAP1/ARE involvement, while highlighting the potential of therapeutic approaches that target DKD via OS.

Synthesis and Evaluation of Functionalized Aryl and Biaryl Isothiocyanates Against Human MCF-7 Cells

Organic isothiocyanates (ITCs) are a class of anticancer agents which naturally result from the enzymatic degradation of glucosinolates produced by Brassica vegetables. Previous studies have demonstrated that the structure of an ITC impacts its potency and mode(s) of anticancer properties, opening the way to preparation and evaluation of synthetic, non-natural ITC analogues. This study describes the preparation of a library of 79 non-natural ITC analogues intended to probe further structure-activity relationships for aryl ITCs and second-generation, functionalized biaryl ITC variants. ITC candidates were subjected to bifurcated evaluation of antiproliferative and antioxidant response element (ARE)-induction capacity against human MCF-7 cells. The results of this study led to the identification of (1) several key structure-activity relationships and (2) lead ITCs demonstrating potent antiproliferative properties.

Dietary phytochemicals targeting Nrf2 for chemoprevention in breast cancer

Breast cancer accounts for 11.7% of all newly diagnosed cancer cases and has become the leading cause of cancer worldwide. Currently, more effective and less toxic chemopreventive strategies for breast cancer are urgently needed. Notably, naturally occurring dietary phytochemical compounds, such as curcumin and resveratrol, are generally considered to be the most promising breast cancer preventive agents. Nuclear factor erythroid 2-related factor 2 (Nrf2) is a transcription factor that plays a key regulatory role in the expression of multiple antioxidant and anti-inflammatory enzymes, which can effectively suppress the excessive accumulation of carcinogens and their metabolites. Therefore, modulation of Nrf2 by dietary phytochemicals appears to be a promising approach for breast cancer prevention, which further removes excessive carcinogenic metabolites by inducing Phase II cytoprotective enzymes such as heme oxygenase-1 (HO-1) and NAD(P)H quinine oxidoreductase 1 (NQO1). In this review, we summarize recently published findings on the prevention of breast cancer with potential natural phytochemical compounds targeting Nrf2, as well as a mechanistic discussion of Nrf2 activation and its contribution in inhibiting breast cancer carcinogenesis. The epigenetic regulation of Nrf2 by phytochemicals is also explored.

Sulforaphane suppresses metastasis of triple-negative breast cancer cells by targeting the RAF/MEK/ERK pathway

Breast cancer metastasis is the main cause of cancer death in women, so far, no effective treatment has inhibited breast cancer metastasis. Sulforaphane (SFN), a natural compound derived from broccoli, has shown potential health benefits in many cancers. However, research on breast cancer metastasis is still insufficient. Here, we showed that SFN, including its two isomers of R-SFN and S-SFN, significantly inhibited TGF-β1-induced migration and invasion in breast cancer cells. Proteomic and phosphoproteomic analysis showed that SFN affected the formation of the cytoskeleton. Subsequent experiments confirmed that SFN significantly inhibited TGF-β1-induced actin stress fiber formation and the expression of actin stress fiber formation-associated proteins, including paxillin, IQGAP1, FAK, PAK2, and ROCK. Additionally, SFN is directly bound to RAF family proteins (including ARAF, BRAF, and CRAF) and inhibited MEK and ERK phosphorylation. These in vitro results indicate that SFN targets the RAF/MEK/ERK signaling pathway to inhibit the formation of actin stress fibers, thereby inhibiting breast cancer cell metastasis.

Contribution of Nanoscience Research in Antioxidants Delivery Used in Nutricosmetic Sector

Nanoscience applications in the food and cosmetic industry offer many potential benefits for consumers and society. Nanotechnologies permit the manipulation of matter at the nanoscale level, resulting in new properties and characteristics useful in food and cosmetic production, processing, packaging, and storage. Nanotechnology protects sensitive bioactive compounds, improves their bioavailability and water solubility, guarantees their release at a site of action, avoids contact with other constituents, and masks unpleasant taste. Biopolymeric nanoparticles, nanofibers, nanoemulsions, nanocapsules, and colloids are delivery systems used to produce food supplements and cosmetics. There are no barriers to nanoscience applications in food supplements and cosmetic industries, although the toxicity of nano-sized delivery systems is not clear. The physicochemical and toxicological characterization of nanoscale delivery systems used by the nutricosmeceutic industry is reviewed in this work.

Nanoparticles as phytochemical carriers for cancer treatment: News of the last decade

INTRODUCTION

The development and application of novel therapeutic medicines for the treatment of cancer are of vital importance to improve the disease's outcome and survival rate. One noteworthy treatment approach is the use of biologically active compounds present in natural products. Even though these phytocompounds present anti-inflammatory, antioxidant, and anticancer properties, their use is limited essentially due to poor systemic delivery, low bioavailability, and water solubility concerns. To make full use of the anticancer potential of natural products, these limitations need to be technologically addressed. In this sense, nanotechnology emerges as a promising drug delivery system strategy.

AREAS COVERED

In this review, the benefits and potential of nanodelivery systems for natural products encapsulation as promising therapeutic approaches for cancer, which were developed during the last decade, are highlighted.

EXPERT OPINION

The nanotechnology area has been under extensive research in the medical field given its capacity for improving the therapeutic potential of drugs by increasing their bioavailability and allowing a targeted delivery to the tumor site. Thereby, the nanoencapsulation of phytocompounds can have a direct impact on the recognized therapeutic activity of natural products towards cancer.

Glucosinolates From Cruciferous Vegetables and Their Potential Role in Chronic Disease: Investigating the Preclinical and Clinical Evidence

An increasing body of evidence highlights the strong potential for a diet rich in fruit and vegetables to delay, and often prevent, the onset of chronic diseases, including cardiometabolic, neurological, and musculoskeletal conditions, and certain cancers. A possible protective component, glucosinolates, which are phytochemicals found almost exclusively in cruciferous vegetables, have been identified from preclinical and clinical studies. Current research suggests that glucosinolates (and isothiocyanates) act via several mechanisms, ultimately exhibiting anti-inflammatory, antioxidant, and chemo-protective effects. This review summarizes the current knowledge surrounding cruciferous vegetables and their glucosinolates in relation to the specified health conditions. Although there is evidence that consumption of a high glucosinolate diet is linked with reduced incidence of chronic diseases, future large-scale placebo-controlled human trials including standardized glucosinolate supplements are needed.

New Generation of Meso and Antiprogestins (SPRMs) into the Osteoporosis Approach

Receptor activator of nuclear factor κB (RANK) and its ligand (RANKL) play key roles in bone metabolism and the immune system. The RANK/RANKL complex has also been shown to be critical in the formation of mammary epithelia cells. The female hormones estradiol and progesterone closely control the action of RANKL with RANK. Blood concentration of these sex hormones in the postmenopausal period leads to an increase in RANK/RANKL signaling and are a major cause of women's osteoporosis, characterized by altered bone mineralization. Knowledge of the biochemical relationships between hormones and RANK/RANKL signaling provides the opportunity to design novel therapeutic agents to inhibit bone loss, based on the anti-RANKL treatment and inhibition of its interaction with the RANK receptor. The new generation of both anti- and mesoprogestins that inhibit the NF-κB-cyclin D1 axis and blocks the binding of RANKL to RANK can be considered as a potential source of new RANK receptor ligands with anti-RANKL function, which may provide a new perspective into osteoporosis treatment itself as well as limit the osteoporosis rise during breast cancer metastasis to the bone.

Sulforaphane: A Broccoli Bioactive Phytocompound with Cancer Preventive Potential

Simple Summary

As of the past decade, phytochemicals have become a major target of interest in cancer chemopreventive and chemotherapeutic research. Sulforaphane (SFN) is a metabolite of the phytochemical glucoraphanin, which is found in high abundance in cruciferous vegetables, such as broccoli, watercress, Brussels sprouts, and cabbage. In both distant and recent research, SFN has been shown to have a multitude of anticancer effects, increasing the need for a comprehensive review of the literature. In this review, we critically evaluate SFN as an anticancer agent and its mechanisms of action based on an impressive number of in vitro, in vivo, and clinical studies.

Abstract

There is substantial and promising evidence on the health benefits of consuming broccoli and other cruciferous vegetables. The most important compound in broccoli, glucoraphanin, is metabolized to SFN by the thioglucosidase enzyme myrosinase. SFN is the major mediator of the health benefits that have been recognized for broccoli consumption. SFN represents a phytochemical of high interest as it may be useful in preventing the occurrence and/or mitigating the progression of cancer. Although several prior publications provide an excellent overview of the effect of SFN in cancer, these reports represent narrative reviews that focused mainly on SFN’s source, biosynthesis, and mechanisms of action in modulating specific pathways involved in cancer without a comprehensive review of SFN’s role or value for prevention of various human malignancies. This review evaluates the most recent state of knowledge concerning SFN’s efficacy in preventing or reversing a variety of neoplasms. In this work, we have analyzed published reports based on in vitro, in vivo, and clinical studies to determine SFN’s potential as a chemopreventive agent. Furthermore, we have discussed the current limitations and challenges associated with SFN research and suggested future research directions before broccoli-derived products, especially SFN, can be used for human cancer prevention and intervention.

Impact of Stilbenes as Epigenetic Modulators of Breast Cancer Risk and Associated Biomarkers

With the recent advancement of genetic screening for testing susceptibility to mammary oncogenesis in women, the relevance of the gene−environment interaction has become progressively apparent in the context of aberrant gene expressions. Fetal exposure to external stressors, hormones, and nutrients, along with the inherited genome, impact its traits, including cancer susceptibility. Currently, there is increasing interest in the role of epigenetic biomarkers such as genomic methylation signatures, plasma microRNAs, and alterations in cell-signaling pathways in the diagnosis and primary prevention of breast cancer, as well as its prognosis. Polyphenols like natural stilbenes have been shown to be effective in chemoprevention by exerting cytotoxic effects that can stall cell proliferation. Besides possessing antioxidant properties against the DNA-damaging effects of reactive oxygen species, stilbenes have also been observed to modulate cell-signaling pathways. With the increasing trend of early-life screening for hereditary breast cancer risks, the potency of different phytochemicals in harnessing the epigenetic biomarkers of breast cancer risk demand more investigation. This review will explore means of exploiting the abilities of stilbenes in altering the underlying factors that influence breast cancer risk, as well as the appearance of associated biomarkers.

Role of Phytonutrients in Nutrigenetics and Nutrigenomics Perspective in Curing Breast Cancer

Breast cancer (BC) is one of the most common type of cancer and an important contributor to female mortality. Several genes and epigenetic modifications are involved in the development and progression of BC. Research in phytochemistry, nutrigenomics, and nutrigenetics has provided strong evidence that certain phytonutrients are able to modulate gene expression at transcriptional and post-transcriptional levels. Such phytonutrients may also be beneficial to prevent and treat BC. In this review, we will focus on the nutrigenomic effects of various phytochemicals including polyphenols, phytosterols, terpenoids, alkaloids, and other compounds from different sources. Overall, these phytonutrients are found to inhibit BC cell proliferation, differentiation, invasion, metastasis, angiogenesis, and induce apoptotic cell death by targeting various molecular pathways. They also alter epigenetic mechanisms and enhance the chemosensitivity and radiosensitivity of cancer cells. Such phytochemicals may be used for the effective management of BC patients in the clinical setting in the future. The present article aims to summarize the specific molecular pathways involved in the genetic effects of phytochemicals in BC.

Sulforaphane alleviates hyperalgesia and enhances analgesic potency of morphine in rats with cancer-induced bone pain

Due to the efficacy and tolerability of the available drugs, the current treatment for cancer-induced bone pain (CIBP) is not considered ideal, and new drugs are required for better treatment results. This study investigated whether intrathecal injection of sulforaphane (SFN) can modulates the noxious behavior associated with CIBP and enhances the analgesic effects of morphine and the possible mechanisms related to these effects were investigated. Walker256 breast cancer cells were injected into the bone marrow cavity of rats to establish the CIBP model. When CIBP rats began to exhibit painful behavior (CIBP 6 days), SFN was injected intrathecally for 7 days. The results showed that SFN alleviated the painful behavioral hypersensitivity caused by cancer, accompanied by nuclear factor, erythroid 2 like 2 (Nrf2), Haem oxygenase 1 (HO-1) activation, nuclear factor kappa B (NF-κB) inhibition and inflammation-related factors (tumor necrosis factor-alpha (TNF-α), interleukin-1β (IL-β), interleukin-6 (IL-6), and inducible nitric oxide synthase (iNOS) reduction. In addition, SFN treatment inhibited the proliferation of Walker 256 cells in a dose-dependent manner, promoted mu-opioid receptor (MOR) expression in SH-SY5Y cells and enhanced the antihyperalgesic effects of morphine on CIBP rats by restoring the downregulation of MOR expression in the spinal cord. Interestingly, the antihyperalgesic effects of SFN were partially blocked by opioid receptor antagonists. This study showed that SFN combined with morphine might be a new way to treat CIBP.

Evaluation of Epigallocatechin-3-Gallate as a Radioprotective Agent During Radiotherapy of Lung Cancer Patients: A 5-Year Survival Analysis of a Phase 2 Study

Background

Previous analysis of the study (NCT02577393) had demonstrated the application of epigallocatechin-3-gallate (EGCG) could be safe and effective in the prevention and treatment of acute radiation esophagitis in patients with advanced lung cancer. EGCG seemed to improve the response rate of small cell lung cancer (SCLC) to radiotherapy in a subgroup analysis. This research continued to analyze the impact of EGCG application on cancer-radiation efficacy and patient survival.

Methods

All patients with SCLC in the NCT02577393 study were included. Patients were randomized into EGCG group or conventional therapy group as protocol. The primary endpoints of the study were radiation response rate and progression-free survival (PFS). Overall survival (OS) and the efficacy of EGCG in the treatment of esophagitis were assessed as secondary endpoints.

Results

A total of 83 patients with lung cancer in the NCT02577393 study were screened, and all 38 patients with SCLC were eligible for analysis. No significant differences with regard to baseline demographic and clinical characteristics were observed between the two groups. The objective response rate (ORR) was higher than that of conventionally treated patients (84.6 vs 50%, P = 0.045), while the median PFS and OS were not significantly prolonged. At data cut-off (1 January 2021), 5-year PFS was 33% with EGCG versus 9.3% with conventional treatment, and 5-year OS was 30.3% versus 33.3%, respectively. The mean adjusted esophagitis index and pain index of patients with EGCG application were lower than conventional treatment (5.15 ± 2.75 vs 7.17 ± 1.99, P = 0.030; 8.62 ± 5.04 vs 15.42 ± 5.04, P < 0.001).

Conclusion

The study indicates EGCG may alleviate some esophagitis-related indexes in SCLC patients exposed to ionizing radiation without reducing survival. However, this conclusion should be confirmed by further studies with large sample size.

Status and Challenges of Plant-Anticancer Compounds in Cancer Treatment

Nowadays, cancer is one of the deadliest diseases in the world, which has been estimated to cause 9.9 million deaths in 2020. Conventional treatments for cancer commonly involve mono-chemotherapy or a combination of radiotherapy and mono-chemotherapy. However, the negative side effects of these approaches have been extensively reported and have prompted the search of new therapeutic drugs. In this context, scientific community started to look for innovative sources of anticancer compounds in natural sources, including traditional plants. Currently, numerous studies have evaluated the anticancer properties of natural compounds derived from plants, both in vitro and in vivo. In pre-clinical stages, some promising compounds could be mentioned, such as the sulforaphane or different phenolic compounds. On the other hand, some phytochemicals obtained positive results in clinical stages and were further approved for cancer treatment, such as vinca alkaloids or the paclitaxel. Nevertheless, these compounds are not exempt of limitations, such as low solubility, restricted effect on their own, negative side-effects, etc. This review aims to compile the information about the current phytochemicals used for cancer treatment and also promising candidates, main action mechanisms and also reported limitations. In this sense, some strategies to face the limitations have been considered, such as nano-based formulations to improve solubility or chemical modification to reduce toxicity. In conclusion, although more research is still necessary to develop more efficient and safe phytochemical drugs, more of these compounds might be used in future cancer therapies.