Effect of Oral Silymarin Administration on Prevention of Radiotherapy Induced Mucositis: A Randomized, Double-Blinded, Placebo-Controlled Clinical Trial

Clinical efficacy and applicability of natural products in the treatment and prevention of radiotherapy-induced oral mucositis: A systematic review

The aim of this systematic review was to describe the efficacy and acceptability of natural products in the management of oral mucositis caused by radiation. From the day it started to August 7, 2023, a thorough search for randomized controlled trials (RCTs) was carried out among seven databases: the Web of Science, PubMed, Embase, OVID, Scopus, the Cochrane Library and the CINAHL database. Only English-language articles were identified during the search. Using the revised Cochrane risk-of-bias tool, version 2, two researchers screened the articles, collected information on study characteristics, and appraised risks of bias. The data were analyzed and descriptively presented with a narrative synthesis methodology involving the Synthesis Without Meta-Analysis (SWiM) reporting element applied in detail. The PROSPERO registration number of this study is CRD42023476932. Thirty-six clinical trials were included in the study; the included studies included a variety of 20 types of natural products. Honey and Curcuma longa were the most commonly assessed natural products. A total of 2,400 participants reported taking part in therapy with natural products for oral mucositis. Natural products demonstrated substantial efficacy in terms of influencing intensity, incidence, pain score, quality of life, and symptoms such as xerostomia and dysphagia. Except for manuka honey, most natural products were well accepted. Regarding the clinical trials' risk of bias, 2 clinical trials (5.56%) had a high risk of bias, 17 studies (47.2%) had a low risk of bias, and 17 studies (47.2%) were rated with "some concern." Natural remedies work well as alternate treatments for managing oral mucositis caused by radiation therapy. However, additional clinical trials are still needed. The safety of these conventional medications as well as their effectiveness and safety when used in combination with other conventional or naturopathic therapies should be fully examined.

Systemic Anti-Inflammatory Agents in the Prevention of Chemoradiation-Induced Mucositis: A Review of Randomised Controlled Trials

Mucositis is a pathological condition characterised by inflammation and ulceration of the mucous membranes lining the alimentary canal, particularly in the mouth (oral mucositis) and the gastrointestinal tract. It is a common side effect of cancer treatments, including chemotherapy and radiotherapy, and it is sometimes responsible for treatment interruptions. Preventing mucositis throughout the alimentary tract is therefore crucial. However, current interventions mainly target either oral or gastrointestinal side effects. This review aimed to investigate the use of systemically administered anti-inflammatory agents to prevent mucositis in cancer patients undergoing cancer treatment. PubMed, Ovid, Scopus, Web of Science, WHO ICTRP and ClinicalTrials.gov were screened to identify eligible randomised controlled trials (RCTs). The published literature on anti-inflammatory agents provides mixed evidence regarding the degree of efficacy in preventing/reducing the severity of mucositis in most anticancer treatments; however, sample size continued to be a significant limitation, alongside others discussed. Our review yielded a list of several anti-inflammatory agents that exhibit potential mucositis-preventive effects in cancer patients undergoing cancer treatment, which can be used to inform clinical practice.

Investigating the effect of Aloe vera on the prevention and treatment of radiotherapy-induced oral mucositis in patients with head-and-neck cancer

Background

Oral mucositis is one of the main complications of radiotherapy (RT) while treating head-and-neck cancers and can affect the patients' treatment process and life. Therefore, this study evaluated the effect of Aloe vera on the prevention and treatment of radiotherapy-induced oral mucositis (RIOM) in patients with head-and-neck cancer.

Materials and Methods

This was a double-blind clinical trial performed in 2019 on 75 patients with head-and-neck cancer. Patients were randomly assigned to two groups receiving gargles of 5 cc Aloe vera and the same dose of placebo mouthwash three times a day, respectively. Then, the incidence and severity of RIOM were evaluated and compared between the two groups over 6 weeks of RT.

Results

There was no significant difference between the two groups in terms of the severity of RIOM from the 1st to 3rd weeks of RT (P > 0.05). However, the severity of RIOM in the 4th, 5th, and 6th weeks of RT was significantly lower in the Aloe vera group compared with the placebo group (P < 0.05).

Conclusion

According to the results of the present study, the long-term use of Aloe vera mouthwash can reduce the severity of RIOM.

Evaluation of the effect of herbal agents as management of radiodermatitis in breast cancer patients: A systematic review and meta-analysis

OBJECTIVE

To evaluate the effectiveness of herbal agents in the prevention and therapy of radiodermatitis in breast cancer patients.

METHODS

Randomized controlled trials were searched from databases such as PubMed, Web of Science, Embase, Cochrane Library, and Chinese National Knowledge Infrastructure (CNKI) to assess the effectiveness of herbal agents compared to a standard medication or placebo in prevention or treatment of radiodermatitis in breast cancer.

RESULTS

Data from 16 studies involving 1994 patients were included. This meta-analysis included 10 clinical trials of 562 breast cancer patients treated with calendula, silymarin, or aloe vera for the prevention of radiodermatitis. Silymarin showed positive effects in ameliorating the damage of radiodermatitis, whereas the efficacy of calendula and aloe vera in the treatment of radiodermatitis lacks sufficient evidence.

CONCLUSIONS

Herbal medicine may show therapeutic effects on radiodermatitis in breast cancer, but more comprehensive investigations and clinical trials are required in the future.

Topical interventions for preventing hand-foot syndrome resulting from antineoplastic therapy: A scoping review

OBJECTIVE

To map topical interventions used to prevent hand-foot syndrome in cancer patients undergoing antineoplastic therapy.

METHOD

This is a scoping review reported in accordance with the recommendations of PRISMA-ScR (extension for scoping review) and the Joanna Briggs Institute Manual. The searches were carried out in the electronic databases CINAHL, Cochrane CENTRAL, EMBASE, LILACS, LIVIVO, PubMed, Scopus, Web of Science; and gray literature (Google Scholar, Pro-Quest).

RESULTS

The searches resulted in 12,016 references and the final sample consisted of 45 studies. A total of 42 topical interventions were identified, including: moisturizing creams, corticosteroids, acids, mapisal, silymarin, and henna. However, urea was the most cited intervention (62%). As for the presentations of the interventions, they varied among creams, ointments, gels, hydrocolloids, decoctions, patches, powders, oils, and soaps.

CONCLUSION

The results allowed reviewing topical interventions, with emphasis on the use of urea and moisturizing creams. However, most of the interventions identified in this review require evaluation in future studies for better understanding of their benefits.

Polyphenols as Potential Protectors against Radiation-Induced Adverse Effects in Patients with Thoracic Cancer

Radiotherapy is one of the standard treatment approaches used against thoracic cancers, occasionally combined with chemotherapy, immunotherapy and molecular targeted therapy. However, these cancers are often not highly sensitive to standard of care treatments, making the use of high dose radiotherapy necessary, which is linked with high rates of radiation-induced adverse effects in healthy tissues of the thorax. These tissues remain therefore dose-limiting factors in radiation oncology despite recent technological advances in treatment planning and delivery of irradiation. Polyphenols are metabolites found in plants that have been suggested to improve the therapeutic window by sensitizing the tumor to radiotherapy, while simultaneously protecting normal cells from therapy-induced damage by preventing DNA damage, as well as having anti-oxidant, anti-inflammatory or immunomodulatory properties. This review focuses on the radioprotective effect of polyphenols and the molecular mechanisms underlying these effects in the normal tissue, especially in the lung, heart and esophagus.

Interventions for the Prevention of Oral Mucositis in Patients Receiving Cancer Treatment: Evidence from Randomised Controlled Trials

Oral mucositis is a common and most debilitating complication associated with cancer therapy. Despite the significant clinical and economic impact of this condition, there is little to offer to patients with oral mucositis, and the medications used in its management are generally only palliative. Given that mucositis is ultimately a predictable and, therefore, potentially preventable condition, in this study we appraised the scientific literature to evaluate effective methods of prevention that have been tested in randomised controlled trials (RCTs). Published high-level evidence shows that multiple preventative methods are potentially effective in the prevention of oral mucositis induced by radiotherapy, chemotherapy, or both. Anti-inflammatory medications (including benzydamine), growth factors and cytokines (including palifermin), cryotherapy, laser-and-light therapy, herbal medicines and supplements, and mucoprotective agents (including oral pilocarpine) showed some degree of efficacy in preventing/reducing the severity of mucositis with most anticancer treatments. Allopurinol was potentially effective in the prevention of radiotherapy-induced oral mucositis; antimicrobial mouthwash and erythropoietin mouthwash were associated with a lower risk of development of severe oral mucositis induced by chemotherapy. The results of our review may assist in highlighting the efficacy and testing the effectiveness of low-cost, safe preventative measures for oral mucositis in cancer patients.

Silymarin as a preventive or therapeutic measure for chemotherapy and radiotherapy-induced adverse reactions: a comprehensive review of preclinical and clinical data

PURPOSE

Thus far, silymarin has been examined in several studies for prevention or treatment of various chemotherapy or radiotherapy-induced adverse reactions. In this review, we try to collect all available human, animal, and pre-clinical data in this field.

METHODS

The search was done in Scopus, PubMed, Medline, and systematic reviews in the Cochrane database, using the following keywords: "Cancer," "Chemotherapy," "Radiotherapy," "Mucositis," "Nephrotoxicity," "Dermatitis," "Ototoxicity," "Cardiotoxicity," "Nephrotoxicity," "Hepatotoxicity," "Reproductive system," "Silybum marianum," "Milk thistle," and "Silymarin" and "Silybin." We included all relevant in vitro, in vivo, and human studies up to the date of publication.

RESULTS

Based on 64 included studies in this review, silymarin is considered a safe and well-tolerated compound, with no known clinical drug interaction. Notably, multiple adverse reactions of chemotherapeutic agents are effectively managed by its antioxidant, anti-apoptotic, anti-inflammatory, and anti-immunomodulatory properties. Clinical trials suggest that oral silymarin may be a promising adjuvant with cancer treatments, particularly against hepatotoxicity (n = 10), nephrotoxicity (n = 3), diarrhea (n = 1), and mucositis (n = 3), whereas its topical formulation can be particularly effective against radiodermatitis (n = 2) and hand-foot syndrome (HFS) (n = 1).

CONCLUSION

Further studies are required to determine the optimal dose, duration, and the best formulation of silymarin to prevent and/or manage chemotherapy and radiotherapy-induced complications.

Mechanistic Insights into the Pharmacological Significance of Silymarin

Medicinal plants are considered the reservoir of diverse therapeutic agents and have been traditionally employed worldwide to heal various ailments for several decades. Silymarin is a plant-derived mixture of polyphenolic flavonoids originating from the fruits and akenes of Silybum marianum and contains three flavonolignans, silibinins (silybins), silychristin and silydianin, along with taxifolin. Silybins are the major constituents in silymarin with almost 70–80% abundance and are accountable for most of the observed therapeutic activity. Silymarin has also been acknowledged from the ancient period and is utilized in European and Asian systems of traditional medicine for treating various liver disorders. The contemporary literature reveals that silymarin is employed significantly as a neuroprotective, hepatoprotective, cardioprotective, antioxidant, anti-cancer, anti-diabetic, anti-viral, anti-hypertensive, immunomodulator, anti-inflammatory, photoprotective and detoxification agent by targeting various cellular and molecular pathways, including MAPK, mTOR, β-catenin and Akt, different receptors and growth factors, as well as inhibiting numerous enzymes and the gene expression of several apoptotic proteins and inflammatory cytokines. Therefore, the current review aims to recapitulate and update the existing knowledge regarding the pharmacological potential of silymarin as evidenced by vast cellular, animal, and clinical studies, with a particular emphasis on its mechanisms of action.

Efficacy of oral and topical antioxidants in the prevention and management of oral mucositis in head and neck cancer patients: a systematic review and meta-analyses

PURPOSE

To evaluate the effectiveness of antioxidants in the prevention and management of oral mucositis in adults undergoing radiotherapy and/or chemotherapy with diagnosed head and neck cancer (HNC) compared to placebo intervention.

METHODS

Cochrane, EMBASE, PubMed, and Web of Science databases were used to search for randomized controlled trials (RCTs) comparing oral or topical antioxidants with placebo in clinically diagnosed HNC adult patients receiving radiotherapy with/without chemotherapy. The primary outcome was to assess the efficacy of the antioxidant to prevent and decrease the incidence/prevalence and severity of oral/oropharyngeal mucositis. The risk of bias was assessed following Cochrane's guidelines.

RESULTS

The database search resulted in 203 records up to February 19, 2021. Thirteen RCTs were included with 650 HNC-diagnosed patients. Included studies showed a statistically significant improvement in mucositis severity score for all antioxidants except melatonin. However, further studies are needed as only one study reported outcomes for zinc, propolis, curcumin, and silymarin. Patients receiving vitamin E were 60% less likely to develop severe mucositis grade 2 or higher than those receiving placebo in one study (P = 0.040). Patients receiving zinc were 95% less likely to develop severe mucositis (grades 3-4) in one study compared to placebo (P = 0.031). One meta-analysis showed no statistical difference in the risk of having severe mucositis (grades 3-4) with 199 patients compared to placebo for honey (n = 2 studies, P = 0.403). Meta-analyses could not be conducted for zinc, propolis, curcumin, melatonin, silymarin, and selenium due to the lack of studies reporting similar outcomes for the same intervention.

CONCLUSION

Though oral and topical antioxidants significantly improved mucositis severity scores in HNC patients receiving radiotherapy with/without chemotherapy in individual studies, the quality of the evidence was low due to the small number of studies and unclear/high-risk bias. Additionally, large RCTs are needed to confirm these results.

Milk thistle (Silybum marianum (L.)Gaertn.): An overview about its pharmacology and medicinal uses with an emphasis on oral diseases

BACKGROUND

Milk thistle, a medicinal plant, has different uses and benefits. Pathologies of the oral cavity manifest as different diseases with various therapeutic options. The main phytochemical extract of the milk thistle plant is silymarin. It has optimistic, protective, and therapeutic properties. However, evidence about the role of milk thistle extracts in oral diseases is lacking.

HIGHLIGHT

The pharmacology of milk thistle was overviewed. The role of the plant in some systemic diseases was reviewed. Furthermore, its role in various oral diseases was discussed. The presented articles described such effects in the context of periodontal disease, dental caries, oral candidiasis, oral lichen planus, oral cancer, and oral mucositis. Results on the promising effects of milk thistle extracts with a preference for silymarin were presented from different research designs. A summary of the previously used doses and the currently available pharmaceutical products was proposed for future research.

CONCLUSION

Milk thistle has antioxidant, anti-inflammatory, anticancer, antifungal, immunomodulatory, and other properties. The evidence from human research about the role of milk thistle in oral diseases is limited. Further studies, particularly clinical trials, to test milk thistle either as a potential treatment modality or a supplementary therapy for oral diseases on higher levels would be useful in the future.

Acupuncture combined with traditional Chinese medicine preparation for the treatment of marrow suppression after chemotherapy: A protocol for systematic review and meta-analysis

BACKGROUND

From the perspective of evidence-based medicine, the efficacy and safety of combined therapy for marrow suppression after chemotherapy is still unclear. Given that there is no high-quality meta-analysis to incorporate existing evidence, the purpose of this protocol is to design a systematically review and meta-analysis of the level I evidence to ascertain the efficacy and safety of acupuncture combined with traditional Chinese medicine preparation for marrow suppression after chemotherapy.

METHODS

The following databases will be searched electronically by keyword combination mode: 4 British literature databases including PubMed, EMBASE, Scopus, and Cochrane Library, and 4 Chinese literature databases, including Chinese national knowledge infrastructure, VIP, and Wan fang database. The randomized controlled trials on acupuncture plus traditional Chinese medicine preparation for marrow suppression after chemotherapy will be included. The primary outcome is the elevation of hemoglobin, platelets, leukocytes, and neutrophils. The other outcomes include clinical symptoms, quality of life, and absolute value of reticulocyte. Risk bias analysis of the studies will be performed independently by 2 reviewers using the Cochrane Risk of Bias Assessment Tool.

RESULTS

The review will add to the existing literature by showing compelling evidence and improved guidance in clinic settings.

CONCLUSION

This protocol will provide a reliable theoretical basis for the following research.

The effects of herbal medicines on cancer therapy-induced oral mucositis: A literature review

Cancer therapy-induced oral mucositis (OM) is one of the most troublesome morbidities after radio-chemotherapy. Age, nutritional status, tumor type, oral hygiene, and treatment method are the determinants for OM incidence. In addition, oxygen-free radicals can act as a trigger for an inflammatory milieu that causes OM. Based on the debilitating nature of OM, finding a safe and inexpensive agent with anti-inflammatory, anti-microbial, and antioxidative properties can be valuable for this situation. Considering the harmful effects of some chemical agents, herbal medicine has been suggested as a potential alternative owing to unique properties such as safety, availability and low cost. Many studies have illustrated several pharmacological properties of herbal medicines in recent years, such as anti-inflammatory, anti-microbial, and antioxidative activities, which are essential factors in the palliation of cancer therapy-induced OM. This review aimed to evaluate herbal medicines' effects on cancer therapy-induced OM. According to this comprehensive review, it is concluded that medicinal plants and phytochemicals can be used as practical agents in the palliation of cancer therapy-induced OM without any serious side effects.

Pharmacological Interventions for the Prevention and Treatment of Kidney Injury Induced by Radiotherapy: Molecular Mechanisms and Clinical Perspectives

More than half of cancer patients need radiotherapy during the course of their treatment. Despite the beneficial aspects, the destructive effects of radiation beams on normal tissues lead to oxidative stress, inflammation, and cell injury. Kidneys are affected during radiotherapy of abdominal malignancies. Radiation nephropathy eventually leads to the release of factors triggering systemic inflammation. Currently, there is no proven prophylactic or therapeutic intervention for the management of radiation-induced nephropathy. This article reviews the biomarkers involved in the pathophysiology of radiation-induced nephropathy and its underlying molecular mechanisms. The efficacy of compounds with potential radio-protective properties on amelioration of inflammation and oxidative stress is also discussed. By outlining the approaches for preventing and treating this critical side effect, we evaluate the potential treatment of radiation-induced nephropathy. Available preclinical and clinical studies on these compounds are also scrutinized.

Prevention of colistin induced nephrotoxicity: a review of preclinical and clinical data

Introduction: The emergence of antimicrobial resistance in Gram-negative bacteria is a concerning challenge for health systems. The polymyxins, including colistin, are one of the limited available options these pathogens management. Nephrotoxicity, beside neurotoxicity is the major dose-limiting adverse reaction of polymyxins, with an up to 60% prevalence. As oxidative stress, inflammatory pathways and apoptosis are considered as the main mechanisms of colistin-induced kidney damage, various studies have evaluated antioxidant and/or antiapoptotic compounds for its prevention. In this article, we reviewed animal and human studies on these probable preventive measures.Area covered: PubMed, Scopus, and google scholar databases were searched using several combination of 'colistin', 'polymyxin E', 'CMS', 'Colistimethate sodium', 'nephrotoxicity', 'kidney injury', 'kidney damage', 'renal injury', 'renal damage', 'nephroprotectants', 'renoprotective', 'nephroprotective', and 'prevention'. All eligible articles including animal and human studies up to the end of 2020 were included.Expert opinion: Most of available studies are in vivo researches on anti-oxidant and anti-apoptotic agents like NAC, vitamin C and E, silymarin, and curcumin which mostly showed promising findings. However, limited human studies on NAC and vitamin C did not demonstrate considerable efficacy. So, before proposing these compounds, further well-designed randomized clinical trials are necessary.

Narrative review of the management of oral mucositis during chemoradiation for head and neck cancer

Oral mucositis (OM) can be a significant problem for patients undergoing radiation or chemoradiation for head and neck cancer. In modern clinical trials, grade 3–4 OM can be seen in over 40% of patients and can cause a significant impact on their quality of life (QOL). Despite this fact, strategies for the prevention and treatment of OM vary widely, with options including both lifestyle modifications and pharmaceuticals. Here we evaluate and summarize the current clinical interventions for the management of radiation-induced OM. The majority of the current evidence focuses on reducing OM related pain. These agents are detailed over multiple clinical trials including treatment modalities such as: GC4419, doxepin mouthwash, diphenhydramine-lidocaine-antacid (DLA) mouthwash, gabapentin, and methadone. While several strategies have been employed to prevent radiation-induced OM, there is currently no strong evidence for the routine use of these agents in the clinic. After summarization of these treatments, we offer practical guidance for the treatment of OM in the clinic. We recommend a multiagent approach of pharmacological and non-pharmacological treatments including oral rinses, home humidification, escalating doses of gabapentin, doxepin or DLA mouthwash, over the counter analgesics, and lastly methadone. These interventions are tailored to address the expected increase of severity of symptoms during the course of head and neck radiotherapy.

Status of Treatment and Prophylaxis for Radiation-Induced Oral Mucositis in Patients With Head and Neck Cancer

Radiation-induced oral mucositis (RIOM) is one of the most frequent complications in head and neck cancer (HNC) patients undergoing radiotherapy (RT). It is a type of mucosal injury associated with severe pain, dysphagia, and other symptoms, which leads to the interruption of RT and other treatments. Factors affecting RIOM include individual characteristics of HNC patients, concurrent chemoradiation therapy, and RT regimen, among others. The pathogenesis of RIOM is not yet fully understood; however, the release of inflammatory transmitters plays an important role in the occurrence and development of RIOM. The five biological stages, including initiation, primary damage response, signal amplification, ulceration, and healing, are widely used to describe the pathophysiology of RIOM. Moreover, RIOM has a dismal outcome with limited treatment options. This review will discuss the epidemiology, pathogenesis, clinical appearance, symptomatic treatments, and preventive measures related to this disease. We hope to provide a reference for the clinical treatment and prevention of RIOM in HNC patients after RT.

Path of Silibinin from diet to medicine: A dietary polyphenolic flavonoid having potential anti-cancer therapeutic significance

In the last few decades, targeting cancer by the use of dietary phytochemicals has gained enormous attention. The plausible reason and believe or mind set behind this fact is attributed to either lesser or no side effects of natural compounds as compared to the modern chemotherapeutics, or due to their conventional use as dietary components by mankind for thousands of years. Silibinin is a naturally derived polyphenol (a flavonolignans), possess following biochemical features; molecular formula C₂₅H₂₂O₁₀, Molar mass: 482.44 g/mol, Boiling point 793 °C, with strikingly high antioxidant and anti-tumorigenic properties. The anti-cancer properties of Silibinin are determined by a variety of cellular pathways which include induction of apoptosis, cell cycle arrest, inhibition of angiogenesis and metastasis. In addition, Silibinin controls modulation of the expression of aberrant miRNAs, inflammatory response, and synergism with existing anti-cancer drugs. Therefore, modulation of a vast array of cellular responses and homeostatic aspects makes Silibinin an attractive chemotherapeutic agent. However, like other polyphenols, the major hurdle to declare Silibinin a translational chemotherapeutic agent, is its lesser bioavailability. After summarizing the chemistry and metabolic aspects of Silibinin, this extensive review focuses on functional aspects governed by Silibinin in chemoprevention with an ultimate goal of summarizing the evidence supporting the chemopreventive potential of Silibinin and clinical trials that are currently ongoing, at a single platform.

Health Benefits of Silybum marianum: Phytochemistry, Pharmacology, and Applications

Silybum marianum (SM), a well-known plant used as both a medicine and a food, has been widely used to treat various diseases, especially hepatic diseases. The seeds and fruits of SM contain a flavonolignan complex called silymarin, the active compounds of which include silybin, isosilybin, silychristin, dihydrosilybin, silydianin, and so on. In this review, we thoroughly summarize high-quality publications related to the pharmacological effects and underlying mechanisms of SM. SM has antimicrobial, anticancer, hepatoprotective, cardiovascular-protective, neuroprotective, skin-protective, antidiabetic, and other effects. Importantly, SM also counteracts the toxicities of antibiotics, metals, and pesticides. The diverse pharmacological activities of SM provide scientific evidence supporting its use in both humans and animals. Multiple signaling pathways associated with oxidative stress and inflammation are the common molecular targets of SM. Moreover, the flavonolignans of SM are potential agonists of PPARγ and ABCA1, PTP1B inhibitors, and metal chelators. At the end of the review, the potential and perspectives of SM are discussed, and these insights are expected to facilitate the application of SM and the discovery and development of new drugs. We conclude that SM is an interesting dietary medicine for health enhancement and drug discovery and warrants further investigation.

Radiation-Induced Oral Mucositis in Head and Neck Cancer Patients. Five Years Literature Review

Backround: Radiation-induced oral mucositis consists of a series of relatively frequent side effects after head and neck cancer radiotherapy and has an adverse impact on both regular treatment process and the quality of life of patients.

OBJECTIVE

The purpose of the present review is to optimize the current management of radiation-induced oral mucositis in head and neck cancer patients.

METHODS

PubMed database research was performed on articles published since 2015 that demonstrated efficacy in the management of radiation-induced oral mucositis in head and neck cancer patients. The study selection included observational, prospective, comparative, randomized, double- blind, placebo-controlled or uncontrolled, and retrospective studies, as well as systematic reviews and metanalyses.

RESULTS

From the 931 citations obtained from the search, only 94 articles met the inclusion criteria, including mucosal protectants, anti-inflammatory agents, growth factors, and various miscellaneous and natural agents. Several methods, including both pharmacological and natural agents, have been proposed for the management of oral mucositis. In addition to the already known interventions with strong evidence, according to the Multinational Association of Supportive Care in Cancer and he International Society of Oral Oncology guidelines, further agents have been used. However, a great number of them lack clear evidence, which surely requires the design of more controlled clinical trials for a better assessment of the ideal methods.

CONCLUSION

The management of oral mucositis constitutes an active area of research. In light of these results, it is aimed to illustrate those treatment strategies that are most effective regarding the treatment approach of oral mucositis.

Oxidative Stress in Radiation-Induced Cardiotoxicity

There is a distinct increase in the risk of heart disease in people exposed to ionizing radiation (IR). Radiation-induced heart disease (RIHD) is one of the adverse side effects when people are exposed to ionizing radiation. IR may come from various forms, such as diagnostic imaging, radiotherapy for cancer treatment, nuclear disasters, and accidents. However, RIHD was mainly observed after radiotherapy for chest malignant tumors, especially left breast cancer. Radiation therapy (RT) has become one of the main ways to treat all kinds of cancer, which is used to reduce the recurrence of cancer and improve the survival rate of patients. The potential cause of radiation-induced cardiotoxicity is unclear, but it may be relevant to oxidative stress. Oxidative stress, an accumulation of reactive oxygen species (ROS), disrupts intracellular homeostasis through chemical modification and damages proteins, lipids, and DNA; therefore, it results in a series of related pathophysiological changes. The purpose of this review was to summarise the studies of oxidative stress in radiotherapy-induced cardiotoxicity and provide prevention and treatment methods to reduce cardiac damage.

Potent Cytotoxic Natural Flavonoids: The Limits of Perspective

BACKGROUND

Besides the numerous biologic and pharmacologic functions in the human body that act as potent antioxidants, flavonoids (flavones, flavanones, flavonols, flavanols and isoflavones) are noted as cancer preventive or therapeutic agents.

METHODS

This review summarizes the published data using PubMed, Science Direct, and Scopus.

RESULTS

In this context, recognition and introduction of the most active cytotoxic flavonoids as promising agents for cancer therapy gives insight for further evaluations. However, there are some critical points that may affect the entering of flavonoids as active cytotoxic phytochemicals in the clinical phase. Issues such as the abundance of active species in nature, the methods of extraction and purification, solubility, pharmacokinetic profile, presence of the chiral moieties, method of synthesis, and structure modification may limit the entry of a selected compound for use in humans. Although plenty of basic evidence exists for cytotoxic/antitumor activity of the versatility of flavonoids for entry into clinical trials, the above-mentioned concerns must be considered.

CONCLUSION

This review is an effort to introduce cytotoxic natural flavonoids (IC50< 10 µM) that may have the potential to be used against various tumor cells. Also, active constituents, molecular mechanisms, and related clinical trials have been discussed as well as the limitations and challenges of using flavonoids in clinic.

Silymarin antiproliferative and apoptotic effects: Insights into its clinical impact in various types of cancer

Silymarin is a complex extract isolated from the plant Silybum marianum, widely known for its prominent antioxidant and hepatoprotective effects, although increasing evidences have reported extraordinary antiproliferative and apoptotic abilities. As a result, several signaling pathways involved in cell cycle control, cell proliferation, and cell death have been deconvoluted as critical mechanisms. In this regard, cyclin and cyclin-dependent pathways have been the most studied ones. Following that, apoptotic pathways, such as p53, Akt, STAT-3, Ras, and caspases pathways, have been extensively studied, although other mechanisms involved in inflammation and angiogenesis have also been highlighted as silymarin-likely targets in cancer therapy. Therefore, the main challenge of this review is to discuss the diverse molecular mechanisms for silymarin antiproliferative and apoptotic effects; most of them largely studied in various types of cancers so far. Clinical trials and combination therapies related to silymarin application in cancer prevention and treatment are presented as well.

Dietary natural flavonoids treating cancer by targeting aryl hydrocarbon receptor

The role of aryl hydrocarbon receptor (AhR) as a ligand-activated transcription factor in the field of cancer has gradually been unveiled. A strong body of evidence indicated that AhR is implicated in cell proliferation and apoptosis, immune metabolism and other processes, which further affected tumor growth, survival, migration, and invasion. Therefore, AhR targeted therapy may become a new method for cancer treatment and provide a new direction for clinical tumor treatment. Astonishingly, the largest source of exposure of animals and humans to AhR ligands (synthetic and natural) comes from the diet. Myriad studies have described that various natural dietary chemicals can directly activate and/or inhibit the AhR signaling pathway. Of note, numerous natural products contribute to AhR active, of which dietary flavonoids are the largest class of natural AhR ligands. As interest in AhR and its ligands increases, it seems sensible to summarize current research on these ligands. In this review, we highlight the role of AhR in tumorigenesis and focus on the double effect of AhR in cancer therapy. We explored the molecular mechanism of AhR ligands on cancer through a few AhR agonists/antagonists currently in clinical practice. Ultimately, we summarize and highlight the latest progression of dietary flavonoids as AhR ligands in cancer inhibition, including the limitations and deficiencies of it in clinical research. This review will offer a comprehensive understanding of AhR and its dietary ligands which may dramatically pave the way for targeted cancer treatment.

Traditional Chinese Medicine Preparation Combined Therapy May Improve Chemotherapy Efficacy: A Systematic Review and Meta-Analysis

Background

Whether traditional Chinese medicine preparation combined therapy can improve the efficacy of chemotherapy is controversial. This meta-analysis evaluates the efficacy of traditional Chinese medicine preparation combined with chemotherapy.

Method

Three databases were searched from inception through August 2018. Eligible randomized controlled trials (RCTs) involving the combined treatment of chemotherapy and traditional Chinese medicine preparation compared to chemotherapy alone for treating cancer were retrieved. The methodological quality of the included RCTs was assessed with Cochrane Collaboration's risk of bias assessment tool. Meta-analysis was adopted to make comprehensive comparisons between the experimental and control groups.

Results

Four RCTs were included in this review, comprising 256 subjects. The majority of the RCTs were judged as being of poor methodological quality. Meta-analysis showed that the combination of traditional Chinese medicine preparation and chemotherapy appeared to be more effective than chemotherapy alone, for the treatment of cancer, as assessed by the disease control rate (RR: 1.41, 95% CI: 1.11 to 1.79) and the objective response rate (RR: 2.71, 95% CI: 1.28 to 5.77). There were no statistically significant differences between the groups in terms of bone marrow suppression (RR: 0.88, 95% CI: 0.57 to 1.37) or gastrointestinal reaction (RR: 1.12, 95% CI 0.75 to 1.69).

Conclusions

Traditional Chinese medicine preparation combined with chemotherapy may improve objective response rates and disease control rates more than chemotherapy alone. The evidence that combined traditional Chinese medicine preparation can reduce the side effects of chemotherapy is insufficient. More rigorous randomized controlled trials are needed to confirm these conclusions.

Safety and toxicity of silymarin, the major constituent of milk thistle extract: An updated review

Milk thistle (Silybum marianum) is a medicinal plant from the Asteraceae family. Silymarin is the major constituent of milk thistle extract and is a mixture of some flavonolignans such as silybin, which is the most active component of silymarin. It is most commonly known for its hepatoprotective effect. Also, studies have shown other therapeutic effects such as anticancer, anti-Alzheimer, anti-Parkinson, and anti-diabetic, so its safety is very important. It has no major toxicity in animals. Silymarin was mutagen in Salmonella typhimurium strains in the presence of metabolic enzymes. Silybin, silydianin, and silychristin were not cytotoxic and genotoxic at concentration of 100 μM. Silymarin is safe in humans at therapeutic doses and is well tolerated even at a high dose of 700 mg three times a day for 24 weeks. Some gastrointestinal discomforts occurred like nausea and diarrhea. One clinical trial showed silymarin is safe in pregnancy, and there were no anomalies. Consequently, caution should be exercised during pregnancy, and more studies are needed especially in humans. Silymarin has low-drug interactions, and it does not have major effects on cytochromes P-450. Some studies demonstrated that the use of silymarin must be with caution when co-administered with narrow therapeutic window drugs.

Formulation of Nanomicelles to Improve the Solubility and the Oral Absorption of Silymarin

Two novel nanomicellar formulations were developed to improve the poor aqueous solubility and the oral absorption of silymarin. Polymeric nanomicelles made of Soluplus and mixed nanomicelles combining Soluplus with d-α-tocopherol polyethylene glycol 1000 succinate (vitamin E TPGS) were prepared using the thin film method. Physicochemical parameters were investigated, in particular the average diameter, the homogeneity (expressed as polydispersity index), the zeta potential, the morphology, the encapsulation efficiency, the drug loading, the critical micellar concentration and the cloud point. The sizes of ~60 nm, the narrow size distribution (polydispersity index ≤0.1) and the encapsulation efficiency >92% indicated the high affinity between silymarin and the core of the nanomicelles. Solubility studies demonstrated that the solubility of silymarin increased by ~6-fold when loaded into nanomicelles. Furthermore, the physical and chemical parameters of SLM-loaded formulations stored at room temperature and in refrigerated conditions (4 °C) were monitored over three months. In vitro stability and release studies in media miming the physiological conditions were also performed. In addition, both formulations did not alter the antioxidant properties of silymarin as evidenced by the 1,1-Diphenyl-2-picrylhydrazyl radical (DPPH) assay. The potential of the nanomicelles to increase the intestinal absorption of silymarin was firstly investigated by the parallel artificial membrane permeability assay. Subsequently, transport studies employing Caco-2 cell line demonstrated that mixed nanomicelles statistically enhanced the permeability of silymarin compared to polymeric nanomicelles and unformulated extract. Finally, the uptake studies indicated that both nanomicellar formulations entered into Caco-2 cells via energy-dependent mechanisms.

Topical silymarin administration for prevention of acute radiodermatitis in breast cancer patients: A randomized, double-blind, placebo-controlled clinical trial

Radiation-induced dermatitis is one of the most common side effects of radiotherapy. Silymarin, a flavonoid extracted from the Silybum marianum, exhibits antioxidant and anti-inflammatory activities. The purpose of this study was to investigate the efficacy of silymarin gel in prevention of radiodermatitis in patients with breast cancer. During this randomized, double-blinded, placebo-controlled clinical trial, the preventive effect of silymarin 1% gel was assessed in comparison with placebo, on radiodermatitis occurrence. Forty patients randomly received silymarin gel or placebo formulation on chest wall skin following modified radical mastectomy, once daily starting at the first day of radiotherapy for 5 weeks. Radiodermatitis severity was assessed weekly based on Radiation Therapy Oncology Group (RTOG) and National Cancer Institute Common Terminology for Adverse Events (NCI-CTCAE) criteria radiodermatits grading scale for 5 weeks. The median NCI-CTCAE and RTOG scores were significantly lower in silymarin group at the end of the third to fifth weeks (p value < 0.05). The scores increased significantly in both placebo and silymarin groups during radiotherapy, but there was a delay in radiodermatitis development and progression in silymarin group. Prophylactic administration of silymarin gel could significantly reduce the severity of radiodermatitis and delay its occurrence after 5 weeks of application.

Effects of silymarin on metabolic syndrome: a review

Metabolic syndrome is one of the rising global health problems and medical challenges due to several clinical complications it may cause, for example increasing the risk of myocardial infarction and hypertension. However, great attention has been directed toward determining the worthiness of herbal medicines. There are emerging studies on preventive and therapeutic effects of silymarin on different components of metabolic syndrome. Extracted from the dried seeds of milk thistle plant (Silybum marianum L.), silymarin has been used in the treatment of different diseases for many years. Several protective effects have been identified for this herb such as decreasing insulin resistance, regulating blood pressure and lipid profile, as well as antioxidant and cytoprotective effects. This review aims to discuss available human and experimental researches into the promising effects of silymarin on different elements of metabolic syndrome. All related human and experimental papers published from 2012 to date were included in this review. Reviewing different human and experimental studies into the effects of silymarin on metabolic syndrome, we deduced that silymarin possesses promising effects on different components of this syndrome. Although the complete mechanism of action and target organs for silymarin require further verification and investigation, high-risk individuals may benefit from supplementation with this herbal medicine. © 2018 Society of Chemical Industry.

Immunomodulatory effects of silymarin after subacute exposure to mice: A tiered approach immunotoxicity screening

Silymarin is a flavonoid complex extracted from the Silybum marianum plant with a wide range of pharmacological and biochemical effects. In the present study, the immunomodulatory effects of silymarin were investigated in BALB/c mice. Silymarin was administered daily by intraperitoneal injection at doses of 50, 100 and 150 mg/kg for 14 consecutive days. Following the exposure, host hematological parameters, spleen cellularity and histopathological examination, as well as delayed-type hypersensitivity (DTH) responses, hemagglutination titers (HA), splenocyte cytokine production and lymphocyte proliferation assay were studied in all of the test groups of animals. The results showed that the low dose of silymarin (50 mg/kg) could stimulate both cellular and humoral immune functions in the treated hosts. In addition, silymarin at 100 mg/kg appeared to impact on DTH responses and lymphoproliferation. Based on the finding here, it would seem that silymarin has efficient immunostimulant properties. As a recommendation, the application of silymarin along with acupuncture technique (herbal acupuncture) can be thought as a good plan to modulate and enhance the immune system for the management of several immunodeficiency disorders. However, further studies are required to demonstrate this hypothesis.

Topical Silymarin Administration for Prevention of Capecitabine-Induced Hand-Foot Syndrome: A Randomized, Double-Blinded, Placebo-Controlled Clinical Trial

Hand-foot syndrome (HFS) is a frequent dose-limiting adverse reaction of capecitabine in patient with gastrointestinal cancers. Silymarin is a polyphenolic flavonoid extracted from the Silybum marianum that exhibits strong antioxidant and antiinflammatory activities. In this study, we evaluated silymarin efficacy in prevention of capecitabine-induced HFS in patients with gastrointestinal cancers, as the first human study. During this pilot, randomized, double-blinded, placebo-controlled clinical trial, the effect of silymarin gel 1%, which is applied on the palms and soles twice daily starting at the first day of chemotherapy for 9 weeks, on HFS occurrence was assessed. Forty patients fulfilled the inclusion criteria assigned to the silymarin or placebo group. World Health Organization HFS grading scale scores were recorded at baseline and every 3 weeks during these 9 weeks. The median WHO HFS scores were significantly lower in silymarin group at the end of the 9th week (p < 0.05). The scores increased significantly in both placebo and silymarin groups during chemotherapy, but there was a delay for HFS development and progression in silymarin group. Prophylactic administration of silymarin topical formulation could significantly reduce the severity of capecitabine-induced HFS and delays its occurrence in patients with gastrointestinal cancer after 9 weeks of application. Copyright © 2017 John Wiley & Sons, Ltd.

Dietary Supplements Commonly Used by Cancer Survivors: Are There Any Benefits?

Following a cancer diagnosis, dietary supplements are reportedly used by 20%-80% of individuals. Supplements are most commonly used by breast cancer survivors, followed by patients with prostate, colorectal, and lung cancers, which is not surprising since these are the most common types of cancer diagnosed in adults. Reasons cited for such use include improving quality of life, reducing symptoms related to treatment and/or the disease process, and recommendation from medical practitioners; family and friends may also be an influence. However, controversy surrounds the use of dietary supplements, particularly during treatment-specifically, whether supplements affect treatment efficacy is unknown. This article discusses the evidence related to common dietary supplements used to prevent cancer or a recurrence.

Effects of Silymarin on Diabetes Mellitus Complications: A Review

Diabetes mellitus is a common metabolic disorder that is caused by a deficit in the production of (type 1) or response to (type 2) insulin. Diabetes mellitus is characterized by a state of chronic hyperglycemia and such symptoms as weight loss, thirst, polyuria, and blurred vision. These disturbances represent one of the major causes of morbidity and mortality nowadays, despite available treatments, such as insulin, insulin secretagogues, insulin sensitizers, and oral hypoglycemic agents. However, many efforts have been made to discover new drugs for diabetes treatment, including medicinal plant extracts. Silymarin is a powder extract of the seeds from Silybum marianum, a plant from the Asteraceae family. The major active ingredients include four isomers: silybin, isosilybin, silychristin, and silydianin. Silymarin is indicated for the treatment of hepatic disorders, such as cirrhosis, chronic hepatitis, and gallstones. Moreover, several studies of other pathologies, including diabetes, sepsis, osteoporosis, arthritis, hypercholesterolemia, cancer, viral infections, and Alzheimer's and Parkinson's diseases, have tested the effects of silymarin and reported promising results. This article reviews data from clinical, in vivo, and in vitro studies on the use of silymarin, with a focus on the complications of diabetes, including nephropathy, neuropathy, healing delays, oxidative stress, hepatotoxicity, and cardiomyopathy. Copyright © 2017 John Wiley & Sons, Ltd.