Magnolin targeting of the JNK/Sp1/MMP15 signaling axis suppresses cervical cancer microenvironment and metastasis via microbiota modulation.

Magnolin (MGL), a compound derived from the magnolia plant, has inhibitory effects on tumor cell invasion and growth. His study aims to explore the antitumor effect and underlying molecular mechanism of MGL against human cervical cancer. We found that MGL inhibited the proliferation, migration, and invasiveness of cervical cancer cells in vitro and in vivo. The underlying mechanism was shown to involve MGL-induced inhibition of JNK/Sp1-mediated MMP15 transcription and translation. Overexpression of JNK/Sp1 resulted in significant restoration of MMP15 expression and the migration and invasion capabilities of MGL-treated cervical cancer cells. MGL modulated the cervical cancer microenvironment by inhibiting cell metastasis via targeting IL-10/IL-10 receptor B (IL-10RB) expression, thereby attenuating JNK/Sp1-mediated MMP15 expression. Analysis of the gut microbiota of mice fed MGL revealed a significant augmentation in Lachnospiraceae bacteria, known for their production of sodium butyrate. In vivo experiments also demonstrated synergistic inhibition of cervical cancer cell metastasis by MGL and sodium butyrate co-administration. Our study provides pioneering evidence of a novel mechanism by which MGL inhibits tumor growth and metastasis through the IL-10/IL-10RB targeting of the JNK/Sp1/MMP15 axis in human cervical cancer cells.

Melatonin acts synergistically with pazopanib against renal cell carcinoma cells through p38 mitogen-activated protein kinase-mediated mitochondrial and autophagic apoptosis.

BACKGROUND: Mounting evidence indicates that melatonin has possible activity against different tumors. Pazopanib is an anticancer drug used to treat renal cell carcinoma (RCC). This study tested the anticancer activity of melatonin combined with pazopanib on RCC cells and explored the underlying mechanistic pathways of its action. METHODS: The 786-O and A-498 human RCC cell lines were used as cell models. Cell viability and tumorigenesis were detected with the MTT and colony formation assays, respectively. Apoptosis and autophagy were assessed using TUNEL, annexin V/propidium iodide, and acridine orange staining with flow cytometry. The expression of cellular signaling proteins was investigated with western blotting. The in vivo growth of tumors derived from RCC cells was evaluated using a xenograft mouse model. RESULTS: Together, melatonin and pazopanib reduced cell viability and colony formation and promoted the apoptosis of RCC cells. Furthermore, the combination of melatonin and pazopanib triggered more mitochondrial, caspase-mediated, and LC3-II-mediated autophagic apoptosis than melatonin or pazopanib alone. The combination also induced higher activation of the p38 mitogen-activated protein kinase (p38MAPK) in the promotion of autophagy and apoptosis by RCC cells than melatonin or pazopanib alone. Finally, tumor xenograft experiments confirmed that melatonin and pazopanib cooperatively inhibited RCC growth in vivo and predicted a possible interaction between melatonin/pazopanib and LC3-II. CONCLUSION: The combination of melatonin and pazopanib inhibits the growth of RCC cells by inducing p38MAPK-mediated mitochondrial and autophagic apoptosis. Therefore, melatonin might be a potential adjuvant that could act synergistically with pazopanib for RCC treatment.

Induction of immunogenic cell death effect of licoricidin in cervical cancer cells by enhancing endoplasmic reticulum stress-mediated high mobility group box 1 expression.

Licoricidin (LCD) is an activity compound of the roots of Glycyrrhiza uralensis, which has therapeutic efficacy, including anti-virus, anti-cancer, and enhanced immunity in Traditional Chinese Medicine. Herein, this study aimed to clarify the effect of LCD on cervical cancer cells. In the present study, we found that LCD significantly inhibited cell viability via inducing cell apoptosis and companies with cleaved-PARP protein expression and caspase-3/-9 activity. Cell viability was markedly reversed these effects by pan-caspase inhibitor Z-VAD-FMK treatment. Furthermore, we showed that LCD-induced ER (endoplasmic reticulum) stress triggers upregulating the protein level of GRP78 (Bip), CHOP, and IRE1α, and subsequently confirmed the mRNA level by quantitative real-time polymerase chain reaction. In addition, LCD exhibited the release of danger-associated molecular patterns from cervical cancer cells, such as the release of high-mobility group box 1 (HMGB1), secretion of ATP, and exposure of calreticulin (CRT) on the cell surface, which led to immunogenic cell death (ICD). These results provide a novel foundation that LCD induces ICD via triggering ER stress in human cervical cancer cells. LCD might be an ICD inducer of immunotherapy in progressive cervical cancer.

Impact of tissue inhibitor of metalloproteinases-3 genetic variants on clinicopathological characteristics of urothelial cell carcinoma.

To investigate the distribution of single nucleotide polymorphism (SNP) of tissue inhibitor of metalloproteinases-3 (TIMP-3) in patients with/without urothelial cell carcinoma (UCC), three loci of TIMP-3 SNPs (rs9862 C/T, rs9619311 T/C, rs11547635 C/T) were genotyped via TaqMan allelic discrimination for 424 UCC patients and 848 non-UCC participants. Furthermore, the TIMP-3 mRNA expression and its correlation with clinical characters of urothelial bladder carcinoma was analyzed using The Cancer Genome Atlas database (TCGA). The distribution of all 3 studied SNPs of TIMP-3 was insignificantly different between the UCC and non-UCC groups. However, significantly lower tumor T status was found in TIMP-3 SNP rs9862 CT + TT variant than the wild type (OR: 0.515, 95% CI: 0.289-0.917, P = 0.023). Moreover, the muscle invasive tumor type was significantly correlated to the TIMP-3 SNP rs9619311 TC + CC variant in the non-smoker subgroup (OR: 2.149, 95% CI: 1.143-4.039, P = 0.016). With the TIMP-3 expression data provided in TCGA, significantly higher TIMP-3 mRNA expression was observed in UCC with high tumor stage (P < 0.0001), high tumor T status (P < 0.0001) and high lymph node status (P = 0.0005). In conclusions, TIMP-3 SNP rs9862 variant is associated with lower tumor T status of UCC while TIMP-3 SNP rs9619311 variant is correlated to muscle invasive UCC development in non-smoker.

Norcantharidin attenuates epidermal growth factor-induced proliferation, EMT and motility in ARPE-19 cells by modulating the AKT/snail/E-cadherin axis.

AIMS: Norcantharidin (NCTD) is a demethylated derivative of cantharidin demonstrated to have anti-proliferative, anti-inflammatory, and anti-fibrosis properties. The purpose of the current study is to investigate the underlying mechanisms and signaling pathways affected by NCTD in human ARPE-19 cells. MAIN METHODS: Cell growth and rate of proliferation were assayed by 3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide (MTT) assay, colony formation assay, and cell cycle distribution/quantification. Cell motility was detected with in vitro migration assay. The level of epithelial-mesenchymal transition (EMT)-related proteins and mRNA (Snail, Slug, E-cadherin) were detected using Western blotting, real-time quantitative polymerase chain reaction, and immunofluorescence assay. Overexpression of Snail plasmid was determined by transfection assay. KEY FINDINGS: We found that NCTD reduced epidermal growth factor (EGF)-induced ARPE-19 cell viability and proliferation through increasing the p21 and p27 expression and decreasing the cyclin D1 expression. NCTD also inhibited EGF-mediated EMT and cell motility through increased protein and mRNA levels of E-cadherin and decreased Snail in EGF-induced ARPE-19 cells. Overexpression of Snail significantly decreased ARPE-19 cell motility and increased E-cadherin expression in NCTD-treated cells. Additionally, when NCTD was combined with a PI3K inhibitor (LY294002) significantly decreased the p-AKT and Snail expression, and increased the E-cadherin expression of EGF treatment in ARPE-19 cells. SIGNIFICANCE: The current findings revealed that NCTD suppresses the EGF-induced proliferation, motility, and EMT of ARPE-19 cells through inactivation of the AKT-mediated Snail/E-cadherin pathway. NCTD may be a potential preventive agent for proliferative vitreoretinopathy.

Melatonin inhibits NaIO3-induced ARPE-19 cell apoptosis via suppression of HIF-1α/BNIP3-LC3B/mitophagy signaling.

BACKGROUND: Age-related macular degeneration (AMD) leads to gradual central vision loss and eventual irreversible blindness. Melatonin, an endogenous hormone, exhibits anti-inflammatory and antitumor effects; however, the role it plays in AMD remains unclear. Herein, we investigated the anti-AMD molecular mechanism of melatonin after sodium iodate (NaIO3) treatment of ARPE-19 cells in vitro and in animal models with the goal of improving the therapeutic effect. RESULTS: The in vitro results showed that melatonin protected against NaIO3-induced cell viability decline, mitochondrial dysfunction and apoptosis in ARPE-19 cells, and melatonin also alleviated NaIO3-induced reactive oxygen species (ROS) production, mitochondrial dysfunction and mitophagy activation. Melatonin reduced NaIO3-induced mitophagy activation through HIF-1α-targeted BNIP3/LC3B transcription, whereas ROS inhibition realized with N-acetylcysteine (NAC, a ROS inhibitor) combined with melatonin reduced the effect of NaIO3 on mitophagy. An animal model of AMD was established to confirm the in vitro data. Mouse tail vein injection of NaIO3 and melatonin was associated with enhanced repair of retinal layers within 7 days, as observed by optical coherence tomography (OCT) and hematoxylin and eosin (H&E) staining. A reduction in BNIP3 and HIF-1α levels, as determined by immunohistochemistry (IHC) assay, was also observed. CONCLUSIONS: These results indicate that melatonin attenuated NaIO3-induced mitophagy of ARPE-19 cells via reduction in ROS-mediated HIF-1α targeted BNIP3/LC3B signaling in vitro and in vivo. Melatonin may be a potential therapeutic drug in the treatment of AMD.

Protodioscin Induces Mitochondrial Apoptosis of Human Hepatocellular Carcinoma Cells Through Eliciting ER Stress-Mediated IP3R Targeting Mfn1/Bak Expression.

Objective: Protodioscin (PD), a steroidal saponin, has a diverse pharmacological activity including neuroprotection, male fertility improvement, and cytotoxicity against various cancers cell lines of different origins. However, the effect of PD on hepatocellular carcinoma (HCC) is still unclear. Methods: Cell viability, colony formation and flow cytometry analysis for apoptosis profile, mitochondrial membrane potential endoplasmic reticulum (ER) expansion were employed to determine the effect of PD against HCC cells. Transient transfection of siRNA, immunofluorescent imaging and immunoprecipitation were used to elucidate the anti-cancer mechanism of PD. The in vivo toxicity and efficacy of PD were assessed by a xenograft mouse model. Results: PD induced apoptosis, loss of mitochondrial membrane potential and ER expansion in HCC cells. Either downregulation of Mfn1 or Bak reversed PD-induced apoptosis and loss of mitochondrial membrane potential. Further analysis revealed that Mfn1 and Bak will form a complex with IP3R to facilitate the transfer of Ca2+ from ER to mitochondria and apoptosis. In addition, our tumour xenograft model further verifies the in vivo anti-tumour effect of PD. Conclusion: Our study sheds light on the understanding of the anti-HCC effects of PD and may open new aspects for the development of novel treatment for human hepatocellular carcinoma.

In Vitro and In Vivo Antifibrotic Effects of Fraxetin on Renal Interstitial Fibrosis via the ERK Signaling Pathway.

Fraxetin, a natural derivative of coumarin, is known to have anti-inflammatory, anti-oxidant, and hepatoprotective effects in multiple diseases and in liver fibrosis. Whether fraxetin exerts similar effects against renal fibrosis is unknown. In a Unilateral Ureteral Obstruction (UUO) mouse model of renal fibrosis, fraxetin decreased UUO-induced renal dysfunction with a marked reduction in renal interstitial collagen fibers as detected by Masson's Trichrome staining. Fraxetin treatment also inhibited the expression of α-SMA, Collagen I, Collagen IV, fibronectin, N-cadherin, vimentin, phosphorylated-ERK, and increased the expression of E-cadherin in UUO mice, as shown by immunohistochemical staining and western blot analysis. In vitro studies showed that fraxetin and indoxyl sulfate had no cytotoxic effects on MES13 kidney cells, but that fraxetin significantly decreased IS-induced cell motility and decreased protein expression of α-SMA, N-cadherin, vimentin, and Collagen IV via the ERK-mediated signaling pathway. These findings provide insight into the mechanism underlying fraxetin-induced inhibition of fibrogenesis in renal tissue and suggest that fraxetin treatment may be beneficial for slowing CKD progression.

Norcantharidin combined with paclitaxel induces endoplasmic reticulum stress mediated apoptotic effect in prostate cancer cells by targeting SIRT7 expression.

Prostate cancer (PCa), an extremely common malignancy in males, is the most prevalent disease in several countries. Norcantharidin (NCTD) has antiproliferation, antimetastasis, apoptosis, and autophagy effects in various tumor cells. Nevertheless, the antitumor effect of NCTD combined with paclitaxel (PTX), a chemotherapeutic drug, in PCa remains unknown. The cell growth, proliferative rate, cell cycle distribution, and cell death were determined by 3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyltetrazolium bromide, colony formation assay, PI staining, and Annexin V/PI staining by flow cytomertry, whereas the mitochondrial membrane potential (MMP) and endoplasmic reticulum (ER) stress was evaluated using the MitoPotential assay and ER-ID red assay. We also evaluated the protein and mRNA expression of SIRTs by Western blotting and qRTPCR assay. Overexpression effectivity was measured by DNA transfection assay. Our study showed that cell viability and proliferative PC3 and DU145 rates were effectively inhibited after NCTD-PTX combination. We also found that NCTD-PTX combination treatment significantly enhance G2/M phase arrest, induction of cell death and ER stress, loss of MMP, and ER- or apoptotic-related protein expression. Furthermore, NCTD-PTX combination treatment was significantly decreasing the protein and mRNA expression of SIRT7 in PCa cells. Combination therapy effectively reduced cell viability, ER stress-mediated apoptosis and p-eIF2α/ATF4/CHOP/cleaved-PARP expression inhibition in SIRT7 overexpression of PCa cells. These results indicate that NCTD combined with PTX induces ER stress-mediated apoptosis of PCa cells by regulating the SIRT7 expression axis. Moreover, combination therapy may become a potential therapeutic strategy against human PCa.

MTA2 silencing attenuates the metastatic potential of cervical cancer cells by inhibiting AP1-mediated MMP12 expression via the ASK1/MEK3/p38/YB1 axis.

Metastasis-associated protein 2 (MTA2) is a transcription factor that is highly associated with matrix metalloproteinase 12 (MMP12). Thus, we hypothesized that MTA2 may regulate MMP12 expression and is involved in cervical cancer metastasis. Results showed that MTA2 and MMP12 were highly expressed in cervical cancer cells, and MTA2 knockdown reduced MMP12 expression and inhibited the metastasis of cervical cancer cells in xenograft mice. MMP12 knockdown did not influence the viability of cervical cancer cells but clearly inhibited cell migration and invasion both in vitro and in vivo. MMP12 was highly expressed in cervical tumor tissues and correlated with the poor survival rate of patients with cervical cancer. Further investigations revealed that p38 mitogen-activated protein kinase (p38), mitogen-activated protein kinase kinase 3 (MEK3), and apoptosis signal-regulating kinase 1 (ASK1) were involved in MMP12 downregulation in response to MTA2 knockdown. Results also demonstrated that p38-mediated Y-box binding protein1 (YB1) phosphorylation disrupted the binding of AP1 (c-Fos/c-Jun) to the MMP12 promoter, thereby inhibiting MMP12 expression and the metastatic potential of cervical cancer cells. Collectively, targeting both MTA2 and MMP12 may be a promising strategy for the treatment of cervical cancer.

Praeruptorin A reduces metastasis of human hepatocellular carcinoma cells by targeting ERK/MMP1 signaling pathway.

Praeruptorin A (PA) is one of the active ingredients found in the dried root of Peucedanum praeruptorum Dunn, has been reported to possess anticancer effects against various types of cancer. However, the effect of PA on human hepatocellular carcinoma (HCC) remains uncleared. In this study, our results indicated that PA did not induce cytotoxicity or alter cell cycle distribution in human HCC cells (Huh-7, SK-Hep-1, and PLC/PRF/5 cells). Instead, PA inhibited the migration and invasion of human HCC cells while downregulating the expression of matrix metalloproteinase-1 (MMP1) and activating the extracellular signal-regulated kinase (ERK) signaling pathways. Furthermore, blocking the ERK signaling pathway through siERK restored the expression of MMP1 and the invasive ability of PA-treated HCC cells. In conclusion, our results demonstrate the antimetastatic activity of PA against human HCC cells, supporting its potential as a therapeutic agent of HCC treatments.

Association of Carbonic Anhydrase 9 Polymorphism and the Epithelial Growth Factor Receptor Mutations in Lung Adenocarcinoma Patients.

Carbonic anhydrase 9 (CA9) plays a vital role in lung cancer progression. The current study explored the effect of CA9 gene polymorphisms and the epidermal growth factor receptor (EGFR) mutations on the clinicopathological characters of lung adenocarcinoma. In this study, three loci of CA9 single nucleotide polymorphism (SNP) (rs2071676 A>G, rs3829078 A>G, and rs1048638 C>A) were genotyped using the TaqMan allelic discrimination method in 193 EGFR wild type individuals and 281 EGFR mutation subjects. After adjusting for age, gender, and cigarette smoking status in logistic regression, all three CA9 SNPs illustrated a non-significant difference for the distribution between the EGFR wild type group and EGFR mutation group. Nevertheless, a significantly lower rate of CA9 SNP rs2071676 AG (adjusted odds ratio (AOR): 0.40, 95% confidence interval (CI): 0.16-0.95, p = 0.039) and AG+GG (AOR: 0.43, 95% CI: 0.18-0.98, p = 0.046) were found in the male population with L858R EGFR mutation compared to men with EGFR wild type. In addition, the CA9 SNP rs2071676 AG+GG genotype were significantly correlated to the lower tumor stage of lung adenocarcinoma in the whole study population (p = 0.044) and EGFR wild type individuals (p = 0.033). For the male population, the presence of CA9 SNP rs2071676 AG+GG genotype was also correlated to a lower tumor stage (p = 0.037) and fewer lymph node invasion (p = 0.003) in those with EGFR wild type. In conclusion, the existence of CA9 SNP rs2071676 is associated with the rate of EGFR L858R mutation in males. Furthermore, the CA9 SNP rs2071676 is correlated to lower tumor stage and lower risk for developing lymph node metastasis in lung adenocarcinoma, mainly in the EGFR wild type.

ß-Mangostin inhibits the metastatic power of cervical cancer cells attributing to suppression of JNK2/AP-1/Snail cascade.

ß-Mangostin is a natural mangostin with potent anticancer activity against various cancers. In this study, we further explored the anticancer activity of ß-mangostin on cervical cancer cells. ß-Mangostin did not affect cell viability and cell cycle distribution in HeLa and SiHa cells; however, it dose-dependently inhibited the migration and invasion of both the human cervical cancer cell lines. In addition, we observed that ß-mangostin suppressed the expression of integrin αV and ß3 and the downstream focal adhesion kinase/Src signaling. We also found that Snail was involved in the ß-mangostin inhibited cell migration and invasion of HeLa cell. Then, our findings showed that ß-mangostin reduced both nuclear translocation and messenger RNA expression of AP-1 and demonstrated that AP-1 could target to the Snail promoter and induce Snail expression. Kinase cascade analysis and reporter assay showed that JNK2 was involved in the inhibition of AP-1/Snail axis by ß-mangostin in HeLa cells. These results indicate that ß-mangostin can inhibit the mobility and invasiveness of cervical cancer cells, which may attribute to the suppression of both integrin/Src signaling and JNK2-mediated AP-1/Snail axis. This suggests that ß-mangostin has potential antimetastatic potential against cervical cancer cells.

Melatonin attenuates epidermal growth factor-induced cathepsin S expression in ARPE-19 cells: Implications for proliferative vitreoretinopathy.

Abnormal proliferation and motility of retinal pigment epithelial cells leads to proliferative vitreoretinopathy (PVR). Melatonin is a known effective antitumour and anti-invasive agent, but whether it affects the formation and underlying mechanisms of PVR remains unclear. In this study, the results of the MTT assay, colony formation and propidium iodide (PI) staining with flow cytometry revealed that melatonin dose dependently inhibited epidermal growth factor (EGF)-induced proliferation of human ARPE-19 cells. Furthermore, melatonin reduced EGF-induced motility by suppressing cathepsin S (CTSS) expression. Pretreatment with ZFL (a CTSS inhibitor) or overexpression of CTSS (pCMV-CTSS) significantly inhibited EGF-induced cell motility when combined with melatonin. Epidermal growth factor induced the phosphorylation of AKT(S473)/mTOR (S2448) and transcription factor (c-Jun/Sp1) signaling pathways. Pretreatment of LY294002 (a PI3K inhibitor) or rapamycin (an mTOR inhibitor) markedly reduced EGF-induced motility and p-AKT/p-mTOR/c-Jun/Sp1 expression when combined with melatonin. Taken together, these data indicate that melatonin inhibited EGF-induced proliferation and motility of human ARPE-19 cells by activating the AKT/mTOR pathway, which is dependent on CTSS modulation of c-Jun/Sp1 signalling. Melatonin may be a promising therapeutic drug against PVR.

Metastasis-associated protein 2 regulates human hepatocellular carcinoma metastasis progression through modulating p38MAPK/MMP2 pathways.

Studies have shown the overexpression of metastasis-associated protein 2 (MTA2) to be associated with hepatocellular carcinoma (HCC) progression. However, the molecular mechanism of MTA2 expression in HCC is unclear. In our study, we found a higher level of MTA2 in HCC tissues than in normal tissues and a significant correlation between tumor grade and overall survival of HCC patients. We also found that MTA2 inhibition reduced the migration and invasion capabilities of HCC cells, independent of cell proliferation. Mechanistic studies have suggested that MTA2 protein and mRNA are more highly expressed in SK-Hep-1 and Huh-7 cells compared with other HCC cells. MTA2 silencing drastically reduced migration and invasion capability and also inhibited matrix metalloproteinase 2 (MMP2) at the transcriptional and translation levels in both cells. In addition, treatment with the MMP2 antibody markedly impaired MTA2-knockdown-mediated inhibition of migration and invasion in SK-Hep-1 cells. Furthermore, MTA2 knockdown reduced the phosphorylation of the p38MAPK protein, whereas the inhibition of p38MAPK (SB203580 or si-p38) confirmed that blocking the p38MAPK pathway mediated MTA2-knockdown-inhibited migration and invasion in SK-Hep-1 cells. We demonstrated the molecular mechanism by which MTA2 inhibits human HCC cell metastasis through the p38MAPK/MMP2 pathways, which might be helpful in determining the diagnostic value of this protein in patients with HCC.

Licochalcone A-Induced Apoptosis Through the Activation of p38MAPK Pathway Mediated Mitochondrial Pathways of Apoptosis in Human Osteosarcoma Cells In Vitro and In Vivo.

BACKGROUND: Licochalcone A (LicA) is isolated from the roots of Glycyrrhiza glabra and possesses antitumor and anti-invasive activities against several tumor cells. However, the antitumor effects of LicA on human osteosarcoma cells have yet to be demonstrated either in vitro or in vivo. METHODS: Cell viability was measured by MTT assay. Apoptosis and mitochondrial dysfunction were detected with Annexin V/PI staining and JC-1 staining by flow cytometry. The expressions of caspase- or mitochondrial-related proteins were demonstrated by western blotting. Antitumor effect of LicA on 143B xenograft mice in vivo. RESULTS: LicA could inhibit cell proliferation and induce apoptosis in human osteosarcoma cells, as evidenced by a decrease in cell viability, loss of mitochondrial membrane potentials, and activation of caspases. LicA treatment substantially reduced the expression of Bcl-2 and Mcl-1 and increased the expression of cleaved-caspase-3, cleaved-caspase-9, cleaved-PARP, and Bax in HOS and U2OS cells. Moreover, mitochondrial membrane potential and apoptosis suppression mediated by Z-VAD or tauroursodeoxycholic acid significantly reduced LicA-induced mitochondria-dependent apoptosis. The study also determined that LicA treatment induced p38MAPK phosphorylation, but siRNA-p38 or BIRB796 substantially reversed cell viability through the inhibition of mitochondria-dependent apoptosis pathways. Finally, an in vivo study revealed that LicA significantly inhibited 143B xenograft tumor growth. CONCLUSIONS: These findings demonstrate that LicA has antitumor activities against human osteosarcoma cells through p38MAPK regulation of mitochondria-mediated intrinsic apoptotic pathways in vitro and in vivo.

Fisetin Suppresses the Proliferation and Metastasis of Renal Cell Carcinoma through Upregulation of MEK/ERK-Targeting CTSS and ADAM9.

Fisetin, a natural flavonoid, is known to have anticarcinogenic effects against several cancers, but its role in mediating renal cell carcinoma (RCC) progression has not been delineated. Cell viability, cytotoxicity, and cell cycle distribution were measured using the 3-(4,5-cimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide assay and propidium iodide staining with flow cytometry. The in vitro migration and invasion assay was used to examine in vivo cell migration and invasion. Human protease antibody array analysis was conducted with cell migration/invasion-related proteins. Western blotting and quantitative reverse transcription polymerase chain reaction were used for assessing protein expression related to the cell cycle, cell invasion, and mitogen-activated protein kinase (MAPK) signaling pathway. We found that fisetin significantly inhibited cell viability through cell cycle arrest in the G2/M phase, in addition to downregulating cyclin D1 and upregulating p21/p27. Fisetin inhibited the migration and invasion of human RCC cells through the downregulation of CTSS and a disintegrin and metalloproteinase 9 (ADAM9). Fisetin also upregulated ERK phosphorylation in 786-O and Caki-1 cells. Furthermore, treatment with a MEK inhibitor (UO126) reduced the inhibitory effects of fisetin on the metastasis of RCC cells through the ERK/CTSS/ADAM9 pathway. Fisetin inhibits proliferation and metastasis of RCC cells by downregulating CTSS and ADAM9 through the MEK/ERK signaling pathway. These findings indicate that fisetin is a promising antitumor agent against RCC.

Repression of metastasis-associated protein 2 for inhibiting metastasis of human oral cancer cells by promoting the p-cofilin-1/ LC3-II expression.

BACKGROUND: The overexpression of metastasis-associated protein 2 (MTA2) contributes to human tumor progression and metastasis in various tumor cells. However, the role of MTA2 in human oral cancer progression remains unknown. MATERIALS AND METHODS: MTA2 expression in human oral tumor tissues and cell lines was measured by immunohistochemistry and Western blotting. Cell proliferation and cell cycle were analyzed using MTT assay and flow cytometry. The effects of MTA2 on oral cell migration and invasion were investigated using migration and invasion assays. The expression of MTA2, p-cofilin-1, and MTA2-induced LC3-II levels were measured using Western blotting and an immunofluorescence assay. RESULTS: Based on the human oral cancer tissue array and TCGA database, we found that MTA2 was increased in oral cancer tissues than in non-tumor oral tissues (P < .01). Moreover, MTA2 is significantly associated with tumor grade (P < .01) and the overall survival rate of patients with grade III tumor (P < .05). MTA2 expression in oral cancer cells was markedly higher than that in normal oral cells. Cell proliferation and cell cycle were not significantly changed in the cells inhibited by MTA2. MTA2 knockdown can inhibit cell migration and invasion of human oral cancer cells. Furthermore, we suggest that MTA2 inhibition enhances p-cofilin and LC3-II expression, and the knockdown of LC3-II expression in cells inhibited by MTA2 had the opposite effect. CONCLUSION: These results indicate that MTA2 may serve as a candidate prognostic biomarker and that targeting autophagy is a potential therapeutic strategy for treating human oral cancer.

Inhibition of eIF2α dephosphorylation accelerates pterostilbene-induced cell death in human hepatocellular carcinoma cells in an ER stress and autophagy-dependent manner.

Hepatocellular carcinoma (HCC) is the one of the most common cancers worldwide. Because the side effects of current treatments are severe, new effective therapeutic strategies are urgently required. Pterostilbene (PT), a natural analogue of resveratrol, has diverse pharmacologic activities, including antioxidative, anti-inflammatory and antiproliferative activities. Here we demonstrated that PT inhibits HCC cell growth without the induction of apoptosis in an endoplasmic reticulum (ER) stress- and autophagy-dependent manner. Mechanistic studies indicated that the combination of salubrinal and PT modulates ER stress-related autophagy through the phospho-eukaryotic initiation factor 2α/activating transcription factor-4/LC3 pathway, leading to a further inhibition of eIF2α dephosphorylation and the potentiation of cell death. An in vivo xenograft analysis revealed that PT significantly reduced tumour growth in mice with a SK-Hep-1 tumour xenograft. Taken together, our results yield novel insights into the pivotal roles of PT in ER stress- and autophagy-dependent cell death in HCC cells.

Praeruptorin-B Inhibits 12-O-Tetradecanoylphorbol-13-Acetate-Induced Cell Invasion by Targeting AKT/NF-κB via Matrix Metalloproteinase-2/-9 Expression in Human Cervical Cancer Cells.

BACKGROUND/AIMS: Praeruptorins, a seselin-type coumarin, possess anti-inflammatory and antitumor promoting properties. However, molecular mechanisms through which Praeruptorin-B (Pra-B) exerts an antimetastatic effect on cervical cancer cells remain unclear. METHODS: Cell viability was examined using the MTT assay, whereas cell migration and invasion were examined using the Boyden chamber assay. Western blotting and RT-PCR were performed to investigate the inhibitory effect of Pra-B on 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced matrix metalloproteinase-2/-9 (MMP-2/-9) expression in HeLa cells. The findings of the luciferase assay confirmed the inhibitory effect of Pra-B on TPA-induced transcriptional activity of MMP2/-9 in HeLa cells. RESULTS: Pra-B inhibited TPA-induced metastatic ability of human cervical cancer cells without any significant toxicity. Pra-B suppressed TPA-induced mRNA and protein expression and transcriptional activity of MMP-2/-9 in HeLa cells. Furthermore, Pra-B inhibited AKT phosphorylation but did not affect the MAPK pathway. Cotreatment of HeLa cells with TPA plus Pra-B or LY294002 (a PI3K inhibitor) reduced cell invasion and MMP-2/-9 expression and transcriptional activity. In addition, Pra-B attenuated TPA-induced nuclear translocation of NF-κB-p65/-p50, which reduced Ikk-α phosphorylation in HeLa cells. Cotreatment of HeLa cells with TPA plus Pra-B or LY294002 reduced NF-κB nuclear translocation. CONCLUSION: These results suggested that Pra-B-mediated inhibition of TPA-induced cell metastasis involved the suppression of p-AKT/NF-κB via MMP-2/-9 expression in HeLa cells. Pra-B can be a potential antimetastatic agent against cervical cancer.