ABSTRACT
Objective: To evaluate the effect of standardized extract of Centella asiatica ECa 233 on inflammatory mediator production through cyclooxygenase-2 (COX-2), extracellular signal-regulated kinase 1/2 (ERK1/2) and nuclear factor-κB (NF-κB) pathway in keratinocyte HaCaT cells. Methods: HaCaT cells were treated with 0.1, 1, 10 and 100 μg/mL ECa 233 in the presence of lipopolysaccharide (LPS). Proinflammatory cytokines and prostaglandin E
ABSTRACT
BACKGROUND/OBJECTIVES: Non-small cell lung cancer is mostly recognized among other types of lung cancer with a poor prognosis by cause of chemotherapeutic resistance and increased metastasis. Luteolin has been found to decrease cell metastasis. However, its underlying mechanisms remain unresolved. The objective of this study was to examine the effect (and its mechanism) of luteolin on the migration and invasion of human non-small cell lung cancer A549 cells.MATERIALS/METHODS: Cell viability was investigated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. Wound healing and transwell assays were evaluated to assess migration and invasion, respectively. Western blot analysis and immunofluorescence were further performed to investigate the role of luteolin and its mechanisms of action.RESULTS: Administration with up to 40 µM luteolin showed no cytotoxic activity on lung cancer A549 cells or non-cancer MRC-5 cells. Additionally, luteolin at 20–40 µM significantly suppressed A549 cells' migration, invasion, and the formation of filopodia in a concentration-dependent manner at 24 h. This is similar with western blot analysis, which revealed diminished the phosphorylated focal adhesion kinase (pFAK), phosphorylated non-receptor tyrosine kinase (pSrc), Ras-related C3 botulinum toxin substrate 1 (Rac1), cell division control protein 42 (Cdc42), and Ras homolog gene family member A (RhoA) expression levels.CONCLUSIONS: Overall, our data indicate that luteolin plays a role in controlling lung cancer cells' migration and invasion via Src/FAK and its downstream Rac1, Cdc42, and RhoA pathways. Luteolin might be considered a promising candidate for suppressing invasion and metastasis of lung cancer cells.
ABSTRACT
BACKGROUND/OBJECTIVES: Re-epithelialization has an important role in skin wound healing. Astaxanthin (ASX), a carotenoid found in crustaceans including shrimp, crab, and salmon, has been widely used for skin protection. Therefore, we investigated the effects of ASX on proliferation and migration of human skin keratinocyte cells and explored the mechanism associated with that migration. MATERIAL/METHOD: HaCaT keratinocyte cells were exposed to 0.25-1 µg/mL of ASX. Proliferation of keratinocytes was analyzed by using MTT assays and flow cytometry. Keratinocyte migration was determined by using a scratch wound-healing assay. A mechanism for regulation of migration was explored via immunocytochemistry and western blot analysis. RESULTS: Our results suggest that ASX produces no significant toxicity in human keratinocyte cells. Cell-cycle analysis on ASX-treated keratinocytes demonstrated a significant increase in keratinocyte cell proliferation at the S phase. In addition, ASX increased keratinocyte motility across the wound space in a time-dependent manner. The mechanism by which ASX increased keratinocyte migration was associated with induction of filopodia and formation of lamellipodia, as well as with increased Cdc42 and Rac1 activation and decreased RhoA activation. CONCLUSIONS: ASX stimulates the migration of keratinocytes through Cdc42, Rac1 activation and RhoA inhibition. ASX has a positive role in the re-epithelialization of wounds. Our results may encourage further in vivo and clinical study into the development of ASX as a potential agent for wound repair.