Efficacy of curcumin for amelioration of radiotherapy-induced oral mucositis: a preliminary randomized controlled clinical trial

Curcumin as a complementary treatment in oncological therapy: a systematic review

PURPOSE

Curcumin, the active ingredient in turmeric, is employed by numerous cancer patients to support conventional cancer therapy. This systematic review aims to summarize the existing clinical evidence and to provide an overview of the potential benefits and risks associated with curcumin supplementation.

METHODS

In January 2024, we conducted a systematic search of five electronic databases (Embase, Cochrane, PsycInfo, CINAHL, and Medline) using a complex search strategy. We included randomized controlled trials on the use, effectiveness, and potential harm of additional curcumin therapy in adult patients under cancer treatment. The risk of bias was assessed using Cochrane revised Risk of Bias Tool 2.0.

RESULTS

This systematic review included 34 randomized controlled trials involving 2580 patients out of 11143 search results. Included patients were primarily diagnosed with head and neck cancer, followed by breast, prostate, and colorectal cancer. Therapy concepts encompassed topical or systemic curcumin administration. The studies reported heterogeneous results concerning oral and skin symptoms, pain, weight alteration and changes in body composition, survival, and disease progression. Significant findings were reported for oral mucositis and weight loss. Considering risk of bias, all studies had moderate to high risk of bias. Regarding side effects, one study reported significantly more vomiting in the curcumin group.

CONCLUSION

Although the results suggest promise in reducing mucositis and weight loss, a clear statement regarding the effectiveness of curcumin therapy on cancer patients cannot be made due to heterogeneous results and methodological limitations of the involved studies. Further investigations of higher quality are necessary to derive a definite recommendation for action.

The Effectiveness of Curcumin in Treating Oral Mucositis Related to Radiation and Chemotherapy: A Systematic Review

Chemotherapy (CT) and radiation therapy (RT), while effective against cancer, often cause severe side effects, such as oral mucositis and other oral diseases. Oral mucositis, characterized by inflammation and ulceration of the oral mucosa, is one of the most painful side effects that can reduce quality of life and limit cancer treatment. Curcumin, a polyphenol from Curcuma longa, has garnered attention for its anti-inflammatory, antioxidant, and anti-carcinogenic properties, which protect the oral mucosa by reducing oxidative stress and modulating inflammation. This study reviews the therapeutic potential of curcumin in preventing and managing oral mucositis caused by CT and RT. Clinical trials show curcumin's effectiveness in reducing the incidence and severity of oral mucositis. Although curcumin supplementation appears to be a promising and cost-effective approach for mitigating oral complications in cancer patients, further clinical trials are needed to confirm its efficacy and optimize dosing strategies.

Effects of Curcumin on Radiation/Chemotherapy-Induced Oral Mucositis: Combined Meta-Analysis, Network Pharmacology, Molecular Docking, and Molecular Dynamics Simulation

The study aims to investigate the effects of curcumin on radiation/chemotherapy-induced oral mucositis (R/CIOM) and preliminarily explore its mechanism. Randomized controlled trials were identified from the PubMed, Embase, Web of Science, Cochrane Library, Medline, and Google Scholar databases. RevMan 5.4 was used for statistical analysis to calculate the combined risk ratios (RRs). The mechanism was analyzed through network pharmacology, molecular docking, and a molecular dynamics simulation. The targets of curcumin were collected in HERB, PharmMapper, Targetnet, Swiss Target Prediction, and SuperPred. OMIM, GeneCards, and Disgenet were used to collect relevant targets for R/CIOM. Cytoscape software 3.8.0 was used to construct the component-target-pathway network. Protein-Protein Interaction (PPI) networks were constructed using the STRING database. GO and KEGG enrichment analyses were performed by Metascape. AutoDock Vina 4.2 software was used for molecular docking. The molecular dynamics simulation was performed by Gromacs v2022.03. It is found that 12 studies involving 565 patients were included. Meta-analyses showed that curcumin reduced the incidence of severe R/CIOM (RR 0.42 [0.24, 0.75]) and the mean severity of R/CIOM (MD -0.93 [-1.34, -0.52]). Eleven core target genes were identified in the treatment of R/CIOM with curcumin. The results of molecular docking and the molecular dynamics simulation showed that curcumin had strong binding energy and stability with target proteins including MAPK3, SRC, and TNF. Overall, these findings suggest curcumin can effectively improve severe R/CIOM, perhaps by affecting MAPK3, SRC, and TNF.

Anti-Cancer Properties of Two Intravenously Administrable Curcumin Formulations as Evaluated in the 3D Patient-Derived Cancer Spheroid Model

Curcumin (Cur) is a heavily used complementary derived drug from cancer patients. Spheroid samples derived from 82 patients were prepared and treated after 48 h with two Cur formulations (CurA, CurB) in mono- and combination therapy. After 72 h, cell viability and morphology were assessed. The Cur formulations had significant inhibitory effects of -8.47% (p < 0.001), CurA of -10.01% (-50.14-23.11%, p = 0.001) and CurB of -6.30% (-33.50-19.30%, p = 0.006), compared to their solvent controls Polyethylene-glycol, β-Cyclodextrin (CurA) and Kolliphor-ELP, Citrate (CurB). Cur formulations were more effective in prostate cancer (-19.54%) and less effective in gynecological non-breast cancers (0.30%). CurA showed better responses in samples of patients <40 (-13.81%) and >70 years of age (-17.74%). CurB had stronger effects in metastasized and heavily pretreated tumors. Combinations of Cur formulations and standard therapies were superior in 20/47 samples (42.55%) and inferior in 7/47 (14.89%). CurB stimulated chemo-doublets more strongly than monotherapies (-0.53% vs. -6.51%, p = 0.022) and more effectively than CurA (-6.51% vs. 3.33%, p = 0.005). Combinations of Cur formulations with Artesunate, Resveratrol and vitamin C were superior in 35/70 (50.00%) and inferior in 16/70 (22.86%) of samples. Cur formulations were significantly enhanced by combination with Artesunate (p = 0.020). Cur formulations showed a high variance in their anti-cancer effects, suggesting a need for individual testing before administration.

New Perspectives about Relevant Natural Compounds for Current Dentistry Research

Natural compounds have been used since the earliest civilizations and remain, to this day, a safer alternative for treating various dental problems. These present antimicrobial, anti-inflammatory, antioxidant, analgesic, and antimutagenic effects, making them useful in the prophylactic and curative treatment of various oral diseases such as infections, gingivitis, periodontitis, and even cancer. Due to the high incidence of unpleasant adverse reactions to synthetic compounds, natural products tend to gradually replace conventional treatment, as they can be just as potent and cause fewer, milder adverse effects. Researchers use several methods to measure the effectiveness and safety profile of these compounds, and employing standard techniques also contributes to progress across all medical disciplines.

Natural Health Products for Anti-Cancer Treatment: Evidence and Controversy

Natural Health Products (NHPs) have long been considered a valuable therapeutic approach for the prevention and treatment of various diseases, including cancer. However, research on this topic has led to inconclusive and often controversial results. This review aims to provide a comprehensive update of the effects and mechanisms related to the use of NHPs, to describe the results of randomized clinical trials (RCTs) on their effects in cancer patients, and to critically discuss factors influencing clinical outcomes. RCTs available in the literature, even those studying the same NHP, are very heterogeneous in terms of indications, doses, route and timing of administration, and outcomes evaluated. Silymarin, ginsenoside, and vitamin E appear to be useful in attenuating adverse events related to radiotherapy or chemotherapy, and curcumin and lycopene might provide some benefit in patients with prostate cancer. Most RCTs have not clarified whether NHP supplementation provides any real benefit, while harmful effects have been shown in some cases. Overall, the available data suggest that although there is some evidence to support the benefits of NHPs in the management of cancer patients, further clinical trials with the same design are needed before their introduction into clinical practice can be considered.

Oral Mucositis Management in Children under Cancer Treatment: A Systematic Review

Children undergoing antineoplastic treatment often present severe side effects due to the dosage and duration of treatments, with oral mucositis emerging as one of the most prevalent and painful inflammatory conditions. There is a growing body of evidence on therapeutic interventions such as cryotherapy, low-level laser therapy, and natural compounds for this condition. The aim of this systematic review was to identify and compare therapies for the management of cancer treatment-induced oral mucositis in pediatric patients. From 2655 articles obtained in initial searches, 39 articles were considered in this systematic review, after applying inclusion/exclusion criteria. Low-level laser therapy, palifermin, honey, and zinc demonstrated reductions in oral mucositis incidence, duration, severity, and pain reported by the patient. Although there are several therapies in place for the prevention and treatment of oral mucositis in children, evidence of their efficacy is still inconclusive to establish accurate clinical protocols.

Efficacy of turmeric in the treatment of oral mucositis in patients with head and neck cancer after radiotherapy or chemoradiotherapy: a systematic review and meta-analysis

Background

Oral mucositis is a major complication for head and neck cancer (HNC) patients after radiotherapy or chemotherapy. A meta-analysis was performed to assess the efficacy of turmeric in the treatment of oral mucositis in HNC patients.

Methods

Randomized controlled trials investigating our topic were included in the meta-analysis. The clinical outcomes considered were the severity of oral mucositis, pain level, and weight loss.

Results

A total of eight articles that met our inclusion criteria were included in our meta-analysis. At the 3-week follow-up visit, the turmeric group showed significantly lower grades of oral mucositis compared to the control group (p = 0.03). When compared to the placebo group, a significant difference in the degree of oral mucositis was observed at the 4-(p = 0.03) and 6-week (p < 0.00001) follow-up visits. No significant difference in pain levels was observed between the turmeric and control groups at any of the follow-up visits. However, a significant improvement in pain levels for the turmeric group when compared with the placebo group was observed only at the 6-week follow-up visit (p = 0.006). Interestingly, a significant improvement in pain levels was observed for the turmeric group at the 2-, 4-, 5-, and 6-week follow-up visits (p < 0.05) when compared to the non-placebo group. The turmeric group showed less weight loss than the control group at the final follow-up visit (p = 0.03).

conclusion

Our meta-analysis showed that using turmeric may be effective in improving both the severity of oral mucositis and pain levels in HNC patients who have received radiotherapy or radiochemotherapy. In addition, the turmeric group experienced less weight loss.

Mitochondrial-targeted curcumin inhibits T-cell activation via Nrf2 and inhibits graft-versus-host-disease in a mouse model

Anti-inflammatory and immune suppressive agents are required to moderate hyper-activation of lymphocytes under disease conditions or organ transplantation. However, selective disruption of mitochondrial redox has not been evaluated as a therapeutic strategy for suppression of T-cell-mediated pathologies. Using mitochondrial targeted curcumin (MitoC), we studied the effect of mitochondrial redox modulation on T-cell responses by flow cytometry, transmission electron microscopy, transcriptomics, and proteomics, and the role of Nrf2 was studied using Nrf2- /- mice. MitoC decreased mitochondrial TrxR activity, enhanced mitochondrial ROS (mROS) production, depleted mitochondrial glutathione, and suppressed activation-induced increase in mitochondrial biomass. This led to suppression of T-cell responses and metabolic reprogramming towards Treg differentiation. MitoC induced nuclear translocation and DNA binding of Nrf2, leading to upregulation of Nrf2-dependent genes and proteins. MitoC-mediated changes in mitochondrial redox and modulation of T-cell responses are abolished in Nrf2- /- mice. Restoration of mitochondrial thiols abrogated inhibition of T-cell responses. MitoC suppressed alloantigen-induced lymphoblast formation, inflammatory cytokines, morbidity, and mortality in acute graft-versus-host disease mice. Disruption of mitochondrial thiols but not mROS increase inculcates an Nrf2-dependent immune-suppressive disposition in T cells for the propitious treatment of graft-versus-host disease.

Plant-Derived Polyphenols to Prevent and Treat Oral Mucositis Induced by Chemo- and Radiotherapy in Head and Neck Cancers Management

Oral Mucositis (OM) is the most common side effect due to chemotherapy and radiotherapy, which are the conventional treatment options for head and neck cancers. OM is a severe inflammatory condition characterized by multifactorial etiopathogenesis. It further negatively affects patients' quality of life by severe impairment of normal oral functions. Consequently, it is mandatory to identify new effective therapeutic approaches to both prevent and treat OM while also avoiding any recurrence. Polyphenols recently attracted the interest of the scientific community due to their low toxicity and wide range of biological activities making them ideal candidates for several applications in the odontostomatological field, particularly against OM. This review collects the in vivo studies and the clinical trials conducted over the past 13 years evaluating the preventive and curative effects of several polyphenolic compounds towards chemo- and radiotherapy-induced OM, both when administered alone or as a plant-extracted phytocomplex. The literature fully confirms the usefulness of these molecules, thus opening the possibility of their clinical application. However, polyphenol limitations (e.g., unfavourable physicochemical properties and susceptibility to degradation) have emerged. Consequently, the interest of the scientific community should be focused on developing innovative delivery systems able to stabilize polyphenols, thus facilitating topical administration and maximizing their efficacy.

Relevance of Phytochemical Taste for Anti-Cancer Activity: A Statistical Inquiry

Targeting inflammation and the pathways linking inflammation with cancer is an innovative therapeutic strategy. Tastants are potential candidates for this approach, since taste receptors display various biological functions, including anti-inflammatory activity (AIA). The present study aims to explore the power different tastes have to predict a phytochemical's anti-cancer properties. It also investigates whether anti-inflammatory phytocompounds also have anti-cancer effects, and whether there are tastes that can better predict a phytochemical's bivalent biological activity. Data from the PlantMolecularTasteDB, containing a total of 1527 phytochemicals, were used. Out of these, only 624 phytocompounds met the inclusion criterion of having 40 hits in a PubMed search, using the name of the phytochemical as the keyword. Among them, 461 phytochemicals were found to possess anti-cancer activity (ACA). The AIA and ACA of phytochemicals were strongly correlated, irrespective of taste/orosensation or chemical class. Bitter taste was positively correlated with ACA, while sweet taste was negatively correlated. Among chemical classes, only flavonoids (which are most frequently bitter) had a positive association with both AIA and ACA, a finding confirming that taste has predictive primacy over chemical class. Therefore, bitter taste receptor agonists and sweet taste receptor antagonists may have a beneficial effect in slowing down the progression of inflammation to cancer.

Nanocarrier-mediated curcumin delivery: An adjuvant strategy for CNS disease treatment

Neurological disorders are a major global challenge, which counts for a substantial slice of disease burden around the globe. In these, the challenging landscape of central nervous system (CNS) diseases, including Alzheimer's disease, Parkinson's disease, multiple sclerosis, and neuro-AIDS, demands innovative and novel therapeutic approaches. Curcumin, a versatile natural compound with antioxidant and anti-inflammatory properties, shows great potential as a CNS adjuvant therapy. However, its limited bioavailability and suboptimal permeability to the blood-brain barrier (BBB) hamper the therapeutic efficacy of curcumin. This review explores how nanocarrier facilitates curcumin delivery, which has shown therapeutic efficacy for various non-CNS diseases, for example, cancers, and can also revolutionize the treatment outcomes in patients with CNS diseases. Toward this, intranasal administration of curcumin as a non-invasive CNS drug delivery route can also aid its therapeutic outcomes as an adjuvant therapy for CNS diseases. Intranasal delivery of nanocarriers with curcumin improves the bioavailability of curcumin and its BBB permeability, which is instrumental in promoting its therapeutic potential. Furthermore, curcumin's inhibitory effect on efflux transporters will help to enhance the BBB and cellular permeability of various CNS drugs. The therapeutic potential of curcumin as an adjuvant has the potential to yield synergistic effects with CNS drugs and will help to reduce CNS drug doses and improve their safety profile. Taken together, this approach holds a promise for reshaping CNS disease management by maximizing curcumin's and other drugs' therapeutic benefits.