Quercetin and Quercitrin from Agrimonia pilosa Ledeb Inhibit the Migration and Invasion of Colon Cancer Cells through the JNK Signaling Pathway.

Considering the high metastatic potential of colorectal cancer (CRC), the inhibition of metastasis is important for anti-CRC therapy. Agrimonia pilosa Ledeb (A. pilosa) is a perennial herbaceous plant that is widely distributed in Asia. The extracts of A. pilosa have shown diverse pharmacological properties, such as antimicrobial, anti-inflammatory, and antitumor activities. In the present study, the antimetastatic activity of A. pilosa was evaluated. Methanol extraction from the roots of A. pilosa was performed by high-performance liquid chromatography (HPLC) and 12 fractions were obtained. Among these, fraction 4 showed the most potent inhibitory effect on the migration of colon cancer cells. Using LC-HR MS analysis, quercetin and quercitrin were identified as flavonoids contained in fraction 4. Like fraction 4, quercetin and quercitrin effectively inhibited the migration and invasion of RKO cells. While the level of E-cadherin was increased, the levels of N-cadherin and vimentin were decreased by the same agents. Although they all activate the p38, JNK, and ERK signaling pathways, only SP600125, an inhibitor of the JNK pathway, specifically inhibited the effect of fraction 4, quercetin, and quercitrin on cell migration. An in vivo experiment also confirmed the antitumor activity of quercetin and quercitrin. Collectively, these results suggest that A. pilosa and its two flavonoids, quercetin and quercitrin, are candidates for the antimetastatic treatment of CRC.

Exopolysaccharide from Lactobacillus plantarum HY7714 Protects against Skin Aging through Skin-Gut Axis Communication.

Skin aging occurs inevitably as a natural result of physiological changes over time. In particular, solar exposure of the skin accounts for up to 90% of skin damage. Numerous studies have examined the ability of dietary constituents to prevent skin aging, and recent research has emphasized the role of functional probiotics in intestinal function and skin aging. However, the mechanism of the interactions between aging and probiotics has not been elucidated yet. The aim of this study was to determine the role of exopolysaccharides (EPS) produced by lactic acid bacteria (LAB) identified as Lactobacillus plantarum HY7714 in regulating tight junctions in intestinal epithelial cells and increasing moisture retention in human dermal fibroblasts cells. We observed that HY7714 EPS controlled intestinal tight junctions in Caco-2 cells by upregulating the genes encoding occludin-1 (OCL-1) and zonula occluden-1 (ZO-1). In addition, HY7714 EPS effectively improved UVB-induced cytotoxicity and hydration capacity in HS68 cells by downregulating production of metalloproteinases (MMPs) and reactive oxygen species (ROS). In summary, HY7714 EPS is an effective anti-aging molecule in skin and may have therapeutic potential against skin diseases and UVB-induced damage. Therefore, HY7714 EPS serves as a functional substance in skin-gut axis communication.

Choline Acetyltransferase Induces the Functional Regeneration of the Salivary Gland in Aging SAMP1/Kl -/- Mice.

Salivary gland dysfunction induces salivary flow reduction and a dry mouth, and commonly involves oral dysfunction, tooth structure deterioration, and infection through reduced salivation. This study aimed to investigate the impact of aging on the salivary gland by a metabolomics approach in an extensive aging mouse model, SAMP1/Klotho -/- mice. We found that the salivary secretion of SAMP1/Klotho -/- mice was dramatically decreased compared with that of SAMP1/Klotho WT (+/+) mice. Metabolomics profiling analysis showed that the level of acetylcholine was significantly decreased in SAMP1/Klotho -/- mice, although the corresponding levels of acetylcholine precursors, acetyl-CoA and choline, increased. Interestingly, the mRNA and protein expression of choline acetyltransferase (ChAT), which is responsible for catalyzing acetylcholine synthesis, was significantly decreased in SAMP1/Klotho -/- mice. The overexpression of ChAT induced the expression of salivary gland functional markers (α-amylase, ZO-1, and Aqua5) in primary cultured salivary gland cells from SAMP1/Klotho +/+ and -/- mice. In an in vivo study, adeno-associated virus (AAV)-ChAT transduction significantly increased saliva secretion compared with the control in SAMP1/Klotho -/- mice. These results suggest that the dysfunction in acetylcholine biosynthesis induced by ChAT reduction may cause impaired salivary gland function.

HOXC6-Mediated miR-188-5p Expression Induces Cell Migration through the Inhibition of the Tumor Suppressor FOXN2.

Homeobox C6 (HOXC6) is a transcription factor that plays a role in the malignant progression of various cancers. However, the roles of HOXC6 and its regulatory mechanism remain unclear. In this study, we used microRNA (miRNA) regulatory networks to identify key regulatory interactions responsible for HOXC6-mediated cancer progression. In microarray profiling of miRNAs, the levels of miRNAs such as hsa-miR-188-5p, hsa-miR-8063, and hsa-miR-8064 were significantly increased in HOXC6-overexpressing cells. Higher positive expression rates of HOXC6 and miR-188-5p were observed in malignant cancer. We also found that HOXC6 significantly upregulated miR-188-5p expression. The underlying function of HOXC6-mediated miR-188-5p expression was predicted through TargetScan and the MiRNA Database. Overexpression of mir-188-5p inhibited the expression of forkhead box N2 (FOXN2), a tumor suppressor gene. Furthermore, in the luciferase assay, miR-188-5p bound to the 3'-UTR of FOXN2 and was mainly responsible for the dysregulation of FOXN2 expression. Silencing FOXN2 induced cell migration, and the effect of FOXN2 silencing was enhanced when the HOXC6/miR-188-5p axis was induced. These results suggest that HOXC6/miR-188-5p may induce malignant progression in cancer by inhibiting the activation of the FOXN2 signaling pathway.

Cinnamaldehyde protects against oxidative stress and inhibits the TNF­α­induced inflammatory response in human umbilical vein endothelial cells.

Oxidative stress and inflammation play critical roles in the development of cardiovascular diseases. Cinnamaldehyde (CA) is a natural compound from Cinnamomum cassia, and its anticancer, antimicrobial and anti­inflammatory activities have been widely investigated. In the present study, the cytoprotective and anti­inflammatory effects of CA on H2O2­ or tumor necrosis factor (TNF)­α­exposed human umbilical vein endothelial cells (HUVECs) were examined. CA and its natural derivative, 2­methoxycinnamaldehyde (MCA), markedly increased the cellular protein level of heme oxygenase­1 (HO­1) and promoted the translocation of nuclear factor erythroid 2­related factor 2 (Nrf2) to the nucleus. CA­mediated Nrf2/HO­1 activation protected the HUVECs from H2O2­induced oxidative stress, which promotes apoptosis. HO­1 depletion by siRNA attenuated the CA­mediated cell protective effects against oxidative stress. Additionally, CA markedly inhibited the adhesion of U937 monocytic cells to HUVECs by decreasing the expression level of vascular cell adhesion protein 1 (VCAM­1). An in vivo experiment confirmed the anti­inflammatory effects of CA, as lipopolysaccharide (LPS)­induced inflammatory cell infiltration was effectively inhibited by the compound. Overall, these observations suggest that CA may be used as a therapeutic agent for oxidative stress­mediated cardiovascular diseases, such as atherosclerosis.

Regulatory effects of Lactobacillus plantarum HY7714 on skin health by improving intestinal condition.

Despite increasing research on the gut-skin axis, there is a lack of comprehensive studies on the improvement of skin health through the regulation of the intestinal condition in humans. In this study, we investigated the benefits of Lactobacillus plantarum HY7714 (HY7714) consumption on skin health through its modulatory effects on the intestine and ensuing immune responses. HY7714 consumption led to differences in bacterial abundances from phylum to genus level, including increases in Actinobacteria followed by Bifidobacterium and a decrease in Proteobacteria. Additionally, HY7714 significantly ameliorated inflammation by reducing matrix metallopeptidases (MMP-2 and MMP-9), zonulin, and calprotectin in plasma, all of which are related to skin and intestinal permeability. Furthermore, RNA-seq analysis revealed its efficacy at restoring the integrity of the gut barrier by regulating gene expression associated with the extracellular matrix and immunity. This was evident by the upregulation of IGFBP5, SERPINE1, EFEMP1, COL6A3, and SEMA3B and downregulation of MT2A, MT1E, MT1X, MT1G, and MT1F between TNF- α and TNF- α plus HY7714 treated Caco-2 cells. These results propose the potential mechanistic role of HY7714 on skin health by the regulation of the gut condition.

Soluble Klotho regulates bone differentiation by upregulating expression of the transcription factor EGR-1.

Klotho is a transmembrane protein known to regulate aging and lifespan. Soluble Klotho (sKL), a truncated form of Klotho, regulates various cell signaling pathways, including bone development. Here, we investigated the relationship between sKL and the zinc finger transcription factor early growth response protein 1 (EGR-1) on bone formation. We find that sKL induces the expression of EGR-1 mRNA and protein. Through mutational analysis, we identify the 130 bp region on the EGR-1 promoter that is responsive to sKL overexpression. Additionally, sKL induces the expression of markers of bone differentiation (BMP2, RUNX2, ALP, COL1A, and osteocalcin) in osteoblast MC3T3 cells. EGR-1 siRNA decreases the bone mineralization induced by sKL or ascorbic acid/glycerol 2-phosphate in MC3T3 cells. Our results suggest that sKL may regulate bone development through EGR-1 expression.

Subacute combined degeneration associated with vitamin E deficiency due to small bowel obstruction: A case report.

RATIONALE: There have been a few reported cases of subacute combined degeneration (SCD) associated with vitamin E deficiency, but the period of intestinal malabsorption was more than several years. We present a rare case of acute onset SCD that occurred in a relatively short period of several weeks with vitamin E deficiency related to small bowel obstruction. PATIENT CONCERNS: A 50-year-old woman had abdominal pain. A small bowel obstruction was suspected and conservative treatment was performed. She underwent bowel surgery after 2 weeks without any improvement. Following the operation, she was in a state of reduced consciousness. She was treated in an intensive care unit. Her consciousness level gradually recovered to alert in a week, but other symptoms such as ataxia, weakness on limbs, severe dysarthria, and dysphagia occurred. Since then, she had spent nearly 6 weeks in a bed-ridden state without improving. DIAGNOSIS: SCD associated with vitamin E deficiency was confirmed by laboratory investigations, electrophysiologic test, and whole spine magnetic resonance imaging scans. INTERVENTIONS: For vitamin E supplementation, she was administered a dose of 1200 mg/d. Physical therapy was focused on strengthening exercise, balance, and walker gait training. Occupational therapy was focused on activities of daily living training and dysphagia rehabilitation. OUTCOMES: After 6 weeks, her muscle strengths and functional level were substantially improved. The vitamin E level was recovered to normal range. LESSONS: This case suggests that if neurological symptoms occur in patients with intestinal obstruction, clinicians need to consider a deficiency of micronutrients such as vitamin E and vitamin B12. Patients with short clinical courses suffer less neurological damage and achieve faster recovery.

Lactobacillus plantarum HY7714 Restores TNF-α Induced Defects on Tight Junctions.

In addition to intestinal balance, probiotics are known to have beneficial effects on skin inflammation, metabolic diseases, and emotions. Previously, we have reported the skin anti-aging effects of Lactobacillus plantarum HY7714 (HY7714) in a clinical trial. To prove the protective skin effects of HY7714 through the intestinal tight junction (TJ), we investigated the effects of HY7714 on the intestines through tumor necrosis factor (TNF)-α induced TJ defects in Caco-2 cells. Specifically, 24 h treatment with HY7714 restored the decreased expression of zonula occludens-1, occludin, and claudin-1 compared to the TNF-α-treated groups (P<0.05). It also attenuated the level of pro-inflammatory cytokines interleukin-6, 8, and 1ß. Further, increases in the mRNA levels of Elk-1, nuclear factor-κB, and myosin light chain kinase expression induced by TNF-α were recovered by HY7714. These findings imply that HY7714 improves intestinal barrier integrity and is a potential therapeutic agent for dysfunctions derived from TJ defects.

Antioxidant modifications induced by the new metformin derivative HL156A regulate metabolic reprogramming in SAMP1/kl (-/-) mice.

Aging is characterized by a reduced ability to defend against stress, an inability to maintain homeostasis, and an increased risk of disease. In this study, a metabolomics approach was used to identify novel metabolic pathways that are perturbed in a mouse model of accelerated aging (SAMP1/kl-/-) and to gain new insights into the metabolic associations of the metformin derivative HL156A. Extensive inflammation and calcification were observed in the tissues of the SAMP1/kl-/- mice with premature aging. In mouse embryonic fibroblasts (MEFs) obtained from SAMP1/kl-/- mice, we observed that HL156A induced FOXO1 expression through inhibition of the IGF-1/AKT/mTOR signaling pathways. Treatment of HL156A decreased reactive oxygen species production and enhanced mitochondrial transmembrane potential in SAMP1/kl-/- MEFs. A metabolomic profile analysis showed that HL156A increased the GSH/GSSG ratio in the kidneys of SAMP1/kl-/- mice (8-12 weeks old). In addition, treating SAMP1/kl-/- mice with HL156A (30 mg/kg) for 4 weeks improved survival and decreased the significant elevation of oxidized GSH (GSSG) that was observed in SAMP1/kl-/- mice. In histological sections, HL156A administered SAMP1/kl-/- mice exhibited a decrease in excessive calcification. Based on these findings, we conclude that the new metformin derivative HL156A may inhibit oxidative damage by inducing glutathione metabolism and antioxidant pathways.

New metformin derivative HL156A prevents oral cancer progression by inhibiting the insulin-like growth factor/AKT/mammalian target of rapamycin pathways.

Metformin is a biguanide widely prescribed as an antidiabetic drug for type 2 diabetes mellitus patients. The purpose of the present study was to observe the effects of the new metformin derivative, HL156A, on human oral cancer cell and to investigate its possible mechanisms. It was observed that HL156A significantly decreased FaDu and YD-10B cell viability and colony formation in a dose-dependent way. HL156A also markedly reduced wound closure and migration of FaDu and YD-10B cells. We observed that HL156A decreased mitochondrial membrane potential and induced reactive oxygen species (ROS) levels and apoptotic cells with caspase-3 and -9 activation. HL156A inhibited the expression and activation of insulin-like growth factor (IGF)-1 and its downstream proteins, AKT, mammalian target of rapamycin (mTOR), and ERK1/2. In addition, HL156A activated AMP-activated protein kinase/nuclear factor kappa B (AMPK-NF-κB) signaling of FaDu and YD-10B cells. A xenograft mouse model further showed that HL156A suppressed AT84 mouse oral tumor growth, accompanied by down-regulated p-IGF-1, p-mTOR, proliferating cell nuclear antigen (PCNA) and promoted p-AMPK and TUNEL expression. These results suggest the potential value of the new metformin derivative HL156A as a candidate for a therapeutic modality for the treatment of oral cancer.

Cinnamaldehyde protects human dental pulp cells against oxidative stress through the Nrf2/HO-1-dependent antioxidant response.

Cinnamaldehyde (CA) has various functional properties, such as anti-cancer, anti-microbial, anti-inflammatory, and anti-oxidant activities. This study examined the intracellular signaling mechanisms of CA on the oxidative stress response in human dental pulp cells (hDPCs). The results showed that CA did not have any cell cytotoxicity or cause morphological changes at concentrations up to 50µM. A CA treatment strongly up-regulated the cellular protein level of heme oxygenase-1 (HO-1) and promoted Nrf2 translocation to the nucleus. CA-mediated Nrf2/HO-1 activation reduced the level of reactive oxygen species and protected the hDPCs from H2O2-induced oxidative stress, which induces apoptosis. Moreover, HO-1 depletion by siRNA attenuated the CA-mediated cell protection against oxidative stress. These results indicate that CA protects hDPCs dysfunction under oxidative stress conditions, and this effect is mediated by Nrf2 activation and the up-regulation of HO-1. Overall, these observations suggest that CA is a potential therapeutic agent for cell protection against oxidative stress.

Cariporide Enhances the DNA Damage and Apoptosis in Acid-tolerable Malignant Mesothelioma H-2452 Cells.

The Na+/H+ exchanger is responsible for maintaining the acidic tumor microenvironment through its promotion of the reabsorption of extracellular Na+ and the extrusion of intracellular H+. The resultant increase in the extracellular acidity contributes to the chemoresistance of malignant tumors. In this study, the chemosensitizing effects of cariporide, a potent Na+/H+-exchange inhibitor, were evaluated in human malignant mesothelioma H-2452 cells preadapted with lactic acid. A higher basal level of phosphorylated (p)-AKT protein was found in the acid-tolerable H-2452AcT cells compared with their parental acid-sensitive H-2452 cells. When introduced in H-2452AcT cells with a concentration that shows only a slight toxicity in H-2452 cells, cariporide exhibited growth-suppressive and apoptosis-promoting activities, as demonstrated by an increase in the cells with pyknotic and fragmented nuclei, annexin V-PE(+) staining, a sub-G0/G1 peak, and a G2/M phase-transition delay in the cell cycle. Preceding these changes, a cariporide-induced p-AKT down-regulation, a p53 up-regulation, an ROS accumulation, and the depolarization of the mitochondrial-membrane potential were observed. A pretreatment with the phosphatidylinositol-3-kinase (PI3K) inhibitor LY294002 markedly augmented the DNA damage caused by the cariporide, as indicated by a much greater extent of comet tails and a tail moment with increased levels of the p-histone H2A.X, p-ATMSer1981, p-ATRSer428, p-CHK1Ser345, and p-CHK2Thr68, as well as a series of pro-apoptotic events. The data suggest that an inhibition of the PI3K/AKT signaling is necessary to enhance the cytotoxicity toward the acid-tolerable H-2452AcT cells, and it underlines the significance of proton-pump targeting as a potential therapeutic strategy to overcome the acidic-microenvironment-associated chemotherapeutic resistance.

2-Methoxycinnamaldehyde inhibits the TNF-α-induced proliferation and migration of human aortic smooth muscle cells.

The abnormal proliferation and migration of vascular smooth muscle cells (VSMCs) is a crucial event in the development of atherosclerosis, and tumor necrosis factor-α (TNF-α) is actively involved in this process by enhancing the proliferation and migration of VSMCs. 2-Methoxycinnamaldehyde (MCA) is a natural compound of Cinnamomum cassia. Although 2-hydroxycinnamaldehyde (HCA), another compound from Cinnamomum cassia, has been widely studied with regard to its antitumor activity, MCA has not attracted researchers' interest due to its mild toxic effects on cancer cells and its mechanisms of action remain unknown. In this study, we examined the effects of MCA on the TNF-α-induced proliferation and migration of human aortic smooth muscle cells (HASMCs). As shown by our results, MCA inhibited TNF-α-induced cell proliferation by reducing the levels of cyclin D1, cyclin D3, CDK4 and CDK6, and increasing the levels of the cyclin-dependent kinase inhibitors, p21 and p27, without resulting in cellular cytotoxicity. Furthermore, MCA decreased the level of secreted matrix metalloproteinase (MMP)-9 by inhibiting MMP-9 transcription. Unexpectedly, MCA did not affect the TNF-α-induced levels of mitogen-activated protein kinases (MAPKs). However, by showing that MCA potently inhibited the degradation of IκBα and the subsequent nuclear translocation of nuclear factor-κB (NF-κB), we demonstrated that MCA exerts its effects through the NF-κB signaling pathway. MCA also effectively inhibited platelet-derived growth factor (PDGF)-induced HASMC migration. Taken together, these observations suggest that MCA has the potential for use as an anti-atherosclerotic agent.

2'-Hydroxycinnamaldehyde induces apoptosis through HSF1-mediated BAG3 expression.

BAG3, a member of BAG co-chaperone family, is induced by stressful stimuli such as heat shock and heavy metals. Through interaction with various binding partners, BAG3 is thought to play a role in cellular adaptive responses against stressful conditions in normal and neoplastic cells. 2'-Hydroxycinnamaldehyde (HCA) is a natural derivative of cinnamaldehyde and has antitumor activity in various cancer cells. In the present study, for the first time, we identified that HCA induced BAG3 expression and BAG3-mediated apoptosis in cancer cells. The apoptotic cell death induced by HCA was demonstrated by caspase-7, -9 and PARP activation, and confirmed by Annexin V staining in both SW480 and SW620 colon cancer cells. Notably, both the mRNA and protein levels of BAG3 were largely induced by HCA in a dose- and time-dependent manner. By showing transcription factor HSF1 activation, we demonstrated that HCA induces the expression of BAG3 through HSF1 activation. More importantly, knockdown of BAG3 expression using siRNA largely inhibited HCA-induced apoptosis, suggesting that BAG3 is actively involved in HCA-induced cancer cell death. Considering the importance of the stress response mechanism in cancer progression, our results strongly suggest that BAG3 could be a potential target for anticancer therapy.

HOXC6 regulates the antitumor effects of pheophorbide a-based photodynamic therapy in multidrug-resistant oral cancer cells.

Photodynamic therapy (PDT) has been considered to be a possible candidate approach for the treatment of multidrug-resistant (MDR) cancer. To investigate the photocytotoxicity of pheophorbide a-based PDT on MDR cells, the intracellular pathways were studied using the human oral cancer FaDu cell line and its paclitaxel-selected subline FaDu-PTX. Pheophorbide a (Pa)-PDT induced significant photocytotoxicity in both FaDu and FaDu-PTX cell lines with cell apoptosis greater in FaDu cells compared to FaDu-PTX cells. We found that Hoxc6 and MDR-1 expression was strongly detected in FaDu-PTX cells compared to FaDu cells. Intriguingly, Pa-PDT effectively reduced Hoxc6 and MDR-1 expression in FaDu-PTX cells. The siRNA for HOXC6 can inhibit the intracellular MDR-1 levels in FaDu-PTX cells and induce the phototoxic effects of Pa-PDT. Furthermore, our in vivo studies showed that the Pa-PDT and HOXC6 siRNA significantly reduce the growth of FaDu-PTX xenograft tumors in C3H mice compared with control- and PTX-treated tumors. Histopathology was also used to confirm this antitumor effect. Pa-PDT may be a potential therapeutic modality for multidrug-resistant cancer, and Hoxc6, as a possible contributor to MDR, may reduce the therapeutic potential in multidrug-resistant oral malignancies.

Pin1 induces the ADP-induced migration of human dental pulp cells through P2Y1 stabilization.

PIN1, which belongs to a family of prolyl isomerases, specifically binds to phosphorylated Ser/Thr-pro motifs to catalytically regulate the post-phosphorylation conformation of its substrates. This study aimed to investigate the importance of Pin1 expression in human dental pulp cells (hDPCs) to understand the involvement of Pin1 in the regulation of P2Y1 and the activation of ADP-mediated P2Y1 signaling. This study found that the protein levels of P2Y1 gradually decreased after the onset of cell recovery following heat stress. Interestedly, hDPC migration significantly decreased during the recovery period. An in vitro study revealed that the silencing of PIN1 by siRNA or the pharmacologic inhibition of its activity decreased the migration of P2Y1 and P2Y1 expression in these cells. In addition, we found that Pin1 directly interacts with S252 of P2Y1 and that its binding stabilizes the P2Y1 protein to increase migration activity. These results strongly suggest that Pin1 mediates cell migration by stabilizing P2Y1 and that the Pin1/P2Y1 signaling pathways might serve as a novel mechanism of cell migration progression in hDPCs.

Hyaluronan suppresses lidocaine-induced apoptosis of human chondrocytes in vitro by inhibiting the p53-dependent mitochondrial apoptotic pathway.

AIM: Intra-articular injection of local anesthetics (LAs) is a common procedure for therapeutic purposes. However, LAs have been found toxic to articular cartilage, and hyaluronan may attenuate this toxicity. In this study we investigated whether hyaluronan attenuated lidocaine-induced chondrotoxicity, and if so, to elucidate the underlying mechanisms. METHODS: Human chondrocyte cell line SW1353 and newly isolated murine chondrocytes were incubated in culture medium containing hyaluronan and/or lidocaine for 72 h. Cell viability was evaluated using MTT assay. Cell apoptosis was detected with DAPI staining, caspase 3/7 activity assay and flow cytometry. Cell cycle distributions, ROS levels and mitochondrial membrane potential (ΔΨm) were determined using flow cytometry. The expression of p53 and p53-regulated gene products was measured with Western blotting. RESULTS: Lidocaine (0.005%-0.03%) dose-dependently decreased the viability of SW1353 cells. This local anesthetic (0.015%, 0.025%) induced apoptosis, G2/M phase arrest and loss of ΔΨm, and markedly increased ROS production in SW1353 cells. Hyaluronan (50-800 µg/mL) alone did not affect the cell viability, but co-treatment with hyaluronan (200 µg/mL) significantly attenuated lidocaine-induced apoptosis and other abnormalities in SW1353 cells. Furthermore, co-treatment with lidocaine and hyaluronan significantly decreased the levels of p53 and its transcription targets Bax and p21 in SW1353 cells, although treatment with lidocaine alone did not significantly change these proteins. Similar results were obtained in ex vivo cultured murine chondrocytes. CONCLUSION: Hyaluronan suppresses lidocaine-induced apoptosis of human chondrocytes in vitro through inhibiting the p53-dependent mitochondrial apoptotic pathway.

Sirtuin inhibitors, EX527 and AGK2, suppress cell migration by inhibiting HSF1 protein stability.

The histone deacetylases (HDACs), Sirtuin 1 (Sirt1) and Sirt2, play crucial roles in many biological processes, including cell proliferation, differentiation and apoptosis. HDAC inhibitors have been considered as a potential therapeutic approach for various types of cancers. Here, we demonstrated that the Sirt1 and Sirt2 inhibitors EX527 and AGK2 suppressed cell growth and caused G1 phase arrest by inhibiting the expression of Cdk6 and/or Cdk4. An agar colony formation assay revealed that EX527 and AGK2 decreased colony formation in soft agar. Furthermore, EX527 and AGK2 pretreatment inhibited the expression of HSF1 and HSP27 and induced HSF1 ubiquitination. Sirt1 overexpression increased HSF1 expression and/or stabilization and induced cell migration in a scratch assay. Overall, these results indicate that EX527 and AGK2 suppress cell growth and migration by inhibiting HSF1 protein stability.

The anticancer mechanism of 2'-hydroxycinnamaldehyde in human head and neck cancer cells.

Cinnamaldehyde has been shown to effectively induce apoptosis in a number of human cancer cells. In the present study, cinnamaldehyde derivative-induced apoptosis and its signaling pathways were assessed in p53-wild (SGT) and p53-mutant (YD-10B) human head and neck cancer cells. The cinnamaldehyde derivatives, 2'-hydroxycinnamaldehyde (HCA) and 2'-benzoyloxycinnamaldehyde (BCA), exhibited powerful anti-proliferative effects on SGT and YD-10B cells. The apoptotic effect induced by HCA or BCA was supported by caspase-3, -7, -9 and PARP activation, and confirmed by Annexin V-FITC/PI double staining. HCA induced the expression of p21 in both SGT and YD-10B cells. Furthermore, HCA induced the level of pro-apoptotic Bak1 expression while decreasing the level of anti-apoptotic Bcl-2 in both cell lines, suggesting that HCA induced the cell death pathway in a p53-independent manner. HCA also induced the expression of LC3B in SGT and YD-10B cells. Following pre-incubation with the autophagy inhibitor 3-MA, HCA-induced apoptosis was largely increased in SGT cells, while inhibited in YD-10B cells, suggesting that autophagy may actively contribute to HCA-induced apoptosis. Taken together, these observations suggest that HCA may be an effective therapeutic agent in the treatment of head and neck cancer regardless of p53 status.