Curcumin downregulates the PI3K-AKT-mTOR pathway and inhibits growth and progression in head and neck cancer cells.

Curcumin, a polyphenol isolated from the rhizome of Curcuma longa, has been studied because of its antioxidant, antimicrobial, and antiinflammatory properties. This study aimed to evaluate the effects of curcumin on head and neck cancer (HNC) cell lines and how it modulates the PI3K-AKT-mTOR signaling pathway. Dose-response curves for curcumin were established for hypopharynx carcinoma (FaDu), tongue carcinoma (SCC-9), and keratinocytes (HaCaT) cell lines and IC50 values were calculated. Cell cycle and cell death were investigated through flow cytometry. Cytoskeleton organization was assessed through phalloidin+FITC staining. qPCR array and western blot were performed to analyze gene and protein expression. Curcumin reduced cell viability in a dose-dependent and selective manner, induced cell death on SCC-9 cells (necrosis/late apoptosis: 44% curcumin vs. 16.4% vehicle), and arrested cell cycle at phase G2 /M on SCC-9 and FaDu (G2 : SCC-9-19.1% curcumin vs. 13.4% vehicle; FaDu-37.8% curcumin vs. 12.9% vehicle). Disorganized cytoskeleton and altered cell morphology were observed. Furthermore, curcumin downregulated the PI3K-AKT-mTOR signaling pathway by modifying the expression of key genes and proteins. These findings highlight the promising therapeutic potential of curcumin to inhibit HNC growth and progression and to modulate the PI3K-AKT-mTOR pathway.

Effects of turmeric and curcumin on oral mucositis: A systematic review.

The aim of this study was to evaluate the effects of turmeric and curcumin in the management of oral mucositis in cancer patients undergoing chemo and/or radiotherapy. The systematic review was reported according to the Preferred Reporting Items for Systematic reviews and Meta-Analyses. The search was performed in the following database: Cochrane Library, LILACS, LIVIVO, PubMed, Scopus, and Web of Science. A gray literature search was undertaken using Google Scholar, Open Grey, and ProQuest. The methodology of included studies was evaluated by the Meta-Analysis of Statistics Assessment and Review Instrument. After a two-step selection process, four randomized and one nonrandomized clinical trials were included in the analysis. Two studies were categorized as low and three as moderate risk of bias. Turmeric/curcumin was applied topically as a gel or as a mouthwash. Patients treated with turmeric/curcumin experienced reduced grade of mucositis, pain, erythema intensity, and ulcerative area. Current evidence suggests that topical application of turmeric or curcumin is effective in controlling signs and symptoms of oral mucositis. Thus, further investigation is required to confirm the promising effect of turmeric and curcumin in oral inflammatory lesions.

In vitro evaluation of wound healing and antimicrobial potential of ozone therapy.

Although ozone therapy is extensively applied when wound repair and antimicrobial effect are necessary, little is known about cellular mechanisms regarding this process. Thus, this study aimed to evaluate ozone cytotoxicity in fibroblasts (L929) and keratinocytes (HaCaT) cell lines, its effects on cell migration and its antimicrobial activity. Cells were treated with ozonated phosphate-buffered saline (8, 4, 2, 1, 0.5 and 0.25 µg/mL ozone), chlorhexidine 0.2% or buffered-solution, and cell viability was determined through MTT assay. The effect of ozone on cell migration was evaluated through scratch wound healing and transwell migration assays. The minimum inhibitory concentrations for Candida albicans and Staphylococcus aureus were determined. Ozone showed no cytotoxicity for the cell lines, while chlorhexidine markedly reduced cell viability. Although no significant difference between control and ozone-treated cells was observed in the scratch assay, a considerable increase in fibroblasts migration was noticed on cells treated with 8 µg/mL ozonated solution. Ozone alone did not inhibit growth of microorganisms; however, its association with chlorhexidine resulted in antimicrobial activity. This study confirms the wound healing and antimicrobial potential of ozone therapy and presents the need for studies to elucidate the molecular mechanisms through which it exerts such biological effects.

In vivo and in vitro effects of curcumin on head and neck carcinoma: a systematic review.

BACKGROUND: Head and neck squamous cell carcinoma (HNSCC) contributes globally to a great number of deaths and morbidity, in spite of new therapeutic strategies. There is a great need of new drugs that are significantly effective and less deleterious to the patients' general health. In this sense, phytotherapy is a tendency, with results pointing to its use as a chemo-preventive and adjuvant therapy. Therefore, the objective of this systematic review was to investigate the effects of curcumin on proliferation and survival of HNSCC. MATERIALS AND METHODS: The search was conducted on six databases: Cochrane, LILACS, EMBASE, MEDLINE, PubMed, and Web of Science. In vitro and in vivo studies that evaluated the effects of curcumin on cell viability, tumor growth, cell cycle and/or cell death pattern in HNSCC cell lines or animal models were selected. RESULTS: Of the 525 initially gathered studies, 30 met the inclusion criteria. These studies demonstrated that curcumin induces cytotoxicity, apoptosis (via intrinsic pathway), and cell cycle arrest in G2 /M phase in HSNCC cell lines. It also reduces tumor measurements in animal models. These events were mostly studied through MTT assay, flow cytometry, and cell cycle- and apoptosis-related proteins expression. CONCLUSION: This systematic review demonstrated that curcumin is effective on HNSCC cell proliferation and survival, reinforcing the currently available evidence that curcumin could be an adjuvant drug in HNSCC treatment.