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Objective. To observe the therapeutic effect of Carvacrol on oral squamous cell carcinoma (OSCC) and dissect underlying molecular mechanisms. Methods. Keap1/Nrf2, NALP3, Vimentin, and E-cadherin expression was detected in OSCC and normal oral mucosa (NOM) tissues using immunofluorescence or western blot. When treated with Carvacrol or tert-butylhydroquinone (TBHQ) that activates Nrf2, the expression of Keap1/Nrf2/HO-1, epithelial-mesenchymal transition- (EMT-) related proteins, and NALP3 was examined in OSCC cells. Nrf2 was silenced by treatment with sh-Nrf2 or ML385. After silencing Nrf2 or Carvacrol treatment, cell proliferation and migration were assessed by clone formation and scratch and transwell tests in OSCC cells. Moreover, the expression of Keap1/Nrf2/HO-1, EMT-related proteins, and NALP3 was detected. Results. Keap1/Nrf2, NALP3, Vimentin, and E-cadherin proteins were all significantly upregulated in OSCC than NOM tissues. Carvacrol significantly suppressed Keap1/Nrf2/HO-1 activation. Carvacrol or silencing Nrf2 markedly inhibited the expression of Keap1/Nrf2/HO-1, EMT-related proteins, and NALP3 inflammasome in OSCC cells. Furthermore, clone formation and migration capacities were suppressed following treatment with Carvacrol or Nrf2 depletion. The opposite results were found when there is overexpression of Nrf2. However, Carvacrol distinctly improved the cancer-promoting effect induced by Nrf2 overexpression. Conclusion. Our findings suggested that Carvacrol ameliorated inflammation, proliferation, and migration for OSCC, which was related to inhibition of the Nrf2/Keap1 pathway. [ABSTRACT FROM AUTHOR]

Objective. To clarify the role and molecular mechanism of mitochondrial calcium uniporter (MCU) in the malignant biological behaviors of oral squamous cell carcinoma (OSCC) cells through clinical and cellular experiments. Methods. Immunohistochemistry and qRT-PCR techniques were used to observe the expression of MCU, nuclear factor erythroid 2-related factor 2 (Nrf2), mitochondrial calcium uptake 1 (MICU1), and MICU2 in OSCC and normal tissues. After treatment with si-MCU, spermine, and/or sh-Nrf2, malignant biological behaviors of OSCC cells including proliferation, migration, and apoptosis were detected by clone formation, migration, and mitochondrial membrane potential (MMP) assays. Furthermore, MCU, MICU1, MICU2, Nrf2, and other proteins related to malignant biological behaviors were examined using western blot, immunohistochemistry, and immunofluorescence assays. Results. MCU, Nrf2, and MICU1 were strongly expressed in OSCC as compared to normal tissues, while MICU2 was relatively weakly expressed in OSCC tissues. Knockdown of MCU distinctly weakened proliferation and migration and lowered MMP level in CAL 27 cells. Conversely, its activation reinforced migrated capacity and increased MMP level in CAL 27 cells, which was reversed after cotransfection with sh-Nrf2. After treatment with si-MCU or spermine, Nrf2 expression was not affected in CAL 27 cells. However, MCU expression was distinctly suppressed in CAL 27 cells transfected with sh-Nrf2. Furthermore, knockdown of Nrf2 significantly reversed the increase in expression of MICU1 and MICU2 induced by MCU activation in CAL 27 cells. Conclusion. MCU, as a novel oncogene of OSCC, augments malignant biological behaviors of OSCC cells, which could be transcriptionally regulated by Nrf2. [ABSTRACT FROM AUTHOR]

The traditional Chinese medicine decoction FuFangChangTai (FFCT) has been used in the therapy of colon cancer clinically, yielding alleviated toxicity and enhanced immunity. In our previous study, FFCT exerted its antitumor activity not only by inducing apoptosis but also by activating autophagy to eliminate tumor cells. However, its mechanism is not well understood. The purpose of this study was to investigate the relationship between macrophages activation and FFCT-induced autophagy. Results showed that FFCT could induce autophagy in colon cancer, as demonstrated by increased level of intracellular autophagy marker LC3 II in CT26.WT cells by fluorescence microscope and western blot assay. FFCT also facilitated numbers of vesicular bodies with bilayer membrane in CT26.WT cells, which were indicative of autophagosomes formation. Autophagosomes secreted by FFCT-treated CT26.WT cells can activate M1 type macrophages, accompanied with increased expression of costimulatory molecules CD86 and CD40 on the surface of RAW264.7 cells, and more inflammatory cytokines secretion, such as TNF-α, IL-6, MCP-1, and IL-1β. mRNA expressions of M2 macrophages markers, such as IL-10, CD206, Arg-1, and FIZZ-1, were downregulated. And this process helps regulate the polarization of macrophages and promote the immune response. These findings support a mechanism of FFCT-induced autophagy and provide novel evidence demonstrating that macrophages are involved in FFCT-induced autophagy progression. [ABSTRACT FROM AUTHOR]