Deoxyshikonin triggers apoptosis in cervical cancer cells through p38 MAPK-mediated caspase activation.

Deoxyshikonin (DSK) is a biological component derived from Lithospermum erythrorhizon. Although DSK possesses potential anticancer activities, whether DSK exerts anticancer effects on cervical cancer cells is incompletely explored. This study was aimed to investigate the anticancer activity of DSK against cervical cancer cells and its molecular mechanisms. Cell viability was evaluated by MTT assay. Level of phosphorylation and protein was determined using Western blot. Involvement of signaling kinases was assessed by specific inhibitors. Our results revealed that DSK reduced viability of human cervical cell in a dose-dependent fashion. Meanwhile, DSK significantly elicited apoptosis of HeLa and SiHa cells. Apoptosis microarray was used to elucidate the involved pathways, and the results showed that DSK dose-dependently diminished cellular inhibitor of apoptosis protein 1 (cIAP1), cIAP2, and XIAP, and induced cleavage of poly(ADP-ribose) polymerase (PARP) and caspase-8/9/3. Furthermore, we observed that DSK significantly triggered activation of ERK, JNK, and p38 MAPK (p38), and only inhibition of p38 diminished the DSK-mediated pro-caspases cleavage. Taken together, our results demonstrate that DSK has anti-cervical cancer effects via the apoptotic cascade elicited by downregulation of IAPs and p38-mediated caspase activation. This suggests that DSK could act as an adjuvant to facilitate cervical cancer management.

Curcumin Analog L48H37 Induces Apoptosis in Human Oral Cancer Cells by Activating Caspase Cascades and Downregulating the Inhibitor of Apoptosis Proteins through JNK/p38 Signaling.

L48H37 is a synthetic curcumin analog that has anticancer potentials. Here, we further explored the anticancer effect of L48H37 on oral cancer cells and its mechanistic acts. Cell cycle distribution was assessed using flow cytometric analysis. Apoptosis was elucidated by staining with PI/Annexin V and activation of the caspase cascade. Cellular signaling was explored using apoptotic protein profiling, Western blotting, and specific inhibitors. Our findings showed that L48H37 significantly reduced the cell viability of SCC-9 and HSC-3 cells, resulting in sub-G1 phase accumulation and increased apoptotic cells. Apoptotic protein profiling revealed that L48H37 increased cleaved caspase-3, and downregulated cellular inhibitor of apoptosis protein 1 (cIAP1) and X-linked inhibitor of apoptosis protein (XIAP) in SCC-9 cells, and the downregulated cIAP1 and XIAP in both oral cancer cells were also demonstrated by Western blotting. Meanwhile, L48H37 triggered the activation of caspases and mitogen-activated protein kinases (MAPKs). The involvement of c-Jun N-terminal kinase (JNK) and p38 MAPK (p38) in the L48H37-triggered apoptotic cascade in oral cancer cells was also elucidated by specific inhibitors. Collectively, these findings indicate that L48H37 has potent anticancer activity against oral cancer cells, which may be attributed to JNK/p38-mediated caspase activation and the resulting apoptosis. This suggests a potential benefit for L48H37 for the treatment of oral cancer.

Gallic acid attenuates metastatic potential of human colorectal cancer cells through the miR-1247-3p-modulated integrin/FAK axis.

Colorectal cancer (CRC) exhibits highly metastatic potential even in the early stages of tumor progression. Gallic acid (GA), a common phenolic compound in plants, is known to possess potent antioxidant and anticancer activities, thereby inducing cell death or cell cycle arrest. However, whether GA reduces the invasiveness of CRC cells without inducing cell death remains unclear. Herein, we aimed to investigate the antimetastatic activity of low-dose GA on CRC cells and determine its underlying mechanism. Cell viability and tumorigenicity were analyzed by MTS, cell adhesion, and colony formation assay. Invasiveness was demonstrated using migration and invasion assays. Changes in protein phosphorylation and expression were assessed by Western blot. The involvement of microRNAs was validated by microarray analysis and anti-miR antagonist. Our findings showed that lower dose of GA (≤100 µM) did not affect cell viability but reduced the capabilities of colony formation, cell adhesion, and invasiveness in CRC cells. Cellularly, GA downregulated the cellular level of integrin αV/ß3, talin-1, and tensin and diminished the phosphorylated FAK, paxillin, Src, and AKT in DLD-1 cells. Microarray results revealed that GA increased miR-1247-3p expression, and pretreatment of anti-miR antagonist against miR-1247-3p restored the GA-reduced integrin αV/ß3 and the GA-inhibited paxillin activation in DLD-1 cells. Consistently, the in vivo xenograft model showed that GA administration inhibited tumor growth and liver metastasis derived from DLD-1 cells. Collectively, our findings indicated that GA inhibited the metastatic capabilities of CRC cells, which may result from the suppression of integrin/FAK axis mediated by miR1247-3p.

The efficacy of adjuvant chemotherapy for older adults with stage II/III gastric cancer: a retrospective cohort study.

BACKGROUND: Adjuvant chemotherapy is recommended as the standard treatment for patients with stage II/III resected gastric cancer. However, it is unclear whether older patients also benefit from an adjuvant chemotherapy strategy. This study aimed to investigate the clinical impact of adjuvant chemotherapy in older patients with stage II/III gastric cancer. METHODS: This retrospective, real-world study analyzed 404 patients with stage II/III gastric cancer visited at our institute between January 2009 and December 2019. The clinical characteristics and outcomes of patients aged 70 years or older who received adjuvant chemotherapy were compared with those who did not receive this type of treatment. Propensity score analysis was performed to mitigate selection bias. RESULTS: Of the 404 patients analyzed, 179 were aged 70 years or older. Fewer older patients received adjuvant chemotherapy than did younger patients (60.9% vs. 94.7%, respectively; P < 0.001). Among patients aged 70 years or older, those who received adjuvant chemotherapy had improved disease-free survival (DFS) (5-year DFS rate, 53.1% vs. 30.4%; P < 0.001) and overall survival (OS) (5-year OS rate, 68.7% vs. 52.1%; P = 0.002) compared to those who did not receive adjuvant chemotherapy. A similar survival benefit was observed in the propensity-matched cohort. Multivariate analysis showed that more advanced stage was associated with poorer OS. Receipt of adjuvant chemotherapy was independently associated with a decreased hazard of death (hazard ratio (HR), 0.37; 95% confidence intervals (CI), 0.20-0.68; P = 0.002). CONCLUSIONS: Adjuvant chemotherapy may benefit older stage II/III gastric cancer patients aged ≥ 70 years. Further prospective studies are needed to confirm these findings.

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.

Differential Serum Proteomic Signatures between Acute Aortic Dissection and Acute Myocardial Infarction.

Acute aortic dissection (AAD) and acute myocardial infarction (AMI) are both severe cardiovascular diseases that may cause sudden death. However, whether serum proteins are differentially expressed between AAD and AMI remains unclear. Here, we aimed to explore serum protein profiles between AAD and AMI patients. A total of 75 serum samples were collected, including AAD patients without AMI (n = 25), AMI patients without AAD (n = 25), and normal subjects (n = 25). Protein identities and expression levels were assessed by LC-MS/MS analysis and a label-free quantitation method, respectively. After depletion of albumin and IgG, a total of 117 proteins with differential expression (fold change ≥2 or ≤−2.0, p < 0.05) were identified, of which 60 were upregulated and 57 were downregulated in AAD sera as compared to AMI sera. Bioinformatic analysis revealed that the differentially expressed serum proteins were mainly derived from exosomes and the extracellular space, and their molecular functions and biological processes were primarily involved in the activity of transporters and complements and the immune response. In addition, the serum level of Cadherin-5, an identified protein with significant regulation in AAD, was further evaluated by ELISA and the results showed that Cadherin-5 in AAD sera was higher that in AMI and healthy sera. Collectively, these findings reveal the differential serum protein profiles between AAD and AMI, which may reflect the divergent pathophysiological progression between the two cardiovascular diseases.

Adenine Combined with Cisplatin Promotes Anticancer Activity against Hepatocellular Cancer Cells through AMPK-Mediated p53/p21 and p38 MAPK Cascades.

Cisplatin has been widely used in cancer treatments. Recent evidence indicates that adenine has potential anticancer activities against various types of cancers. However, the effects of the combination of adenine and cisplatin on hepatocellular carcinoma (HCC) cells remain sketchy. Here, our objective was to elucidate the anticancer activity of adenine in combination with cisplatin in HCC cells and its mechanistic pathways. Cell viability and cell cycle progression were assessed by the SRB assay and flow cytometry, respectively. Apoptosis was demonstrated by PI/annexin V staining and flow cytometric analysis. Protein expression, signaling cascade, and mRNA expression were analyzed by Western blotting and quantitative RT-PCR, respectively. Our results showed that adenine jointly potentiated the inhibitory effects of cisplatin on the cell viability of SK-Hep1 and Huh7 cells. Further investigation showed that adenine combined with cisplatin induced higher S phase arrest and apoptosis in HCC cells. Mechanically, adenine induced AMPK activation, reduced mTOR phosphorylation, and increased p53 and p21 levels. The combination of adenine and cisplatin synergistically reduced Bcl-2 and increased PUMA, cleaved caspase-3, and PARP in HCC cells. Adenine also upregulated the mRNA expression of p53, p21, PUMA, and PARP, while knockdown of AMPK reduced the increased expression of these genes. Furthermore, adenine also induced the activation of p38 MAPK through AMPK signaling, and the inhibition of p38 MAPK reduced the apoptosis of HCC cells with exposure to adenine combined with cisplatin. Collectively, these findings reveal that the combination of adenine and cisplatin synergistically enhances apoptosis of HCC cells, which may be attributed to the AMPK-mediated p53/p21 and p38 MAPK cascades. It suggests that adenine may be a potential adjuvant for the treatment of HCC in combination with cisplatin.

Rosmarinic Acid Attenuates the Lipopolysaccharide-Provoked Inflammatory Response of Vascular Smooth Muscle Cell via Inhibition of MAPK/NF-κB Cascade.

Rosmarinic acid (RA) is a phenolic compound that has several bioactivities, such as anti-inflammatory and antioxidant activities. Here, we further investigate the anti-inflammatory effect of RA on rat A7r5 aortic smooth muscle cells with exposure to lipopolysaccharide (LPS). Our findings showed that low-dose RA (10-25 µM) did not influence the cell viability and morphology of A7r5 cells and significantly inhibited LPS-induced mRNA expression of the pro-inflammatory mediators TNFα, IL-8, and inducible NO synthase (iNOS). Consistently, RA reduced the production of TNFα, IL-8, and NO by A7r5 cells with exposure to LPS. Signaling cascade analysis showed that LPS induced activation of Erk, JNK, p38 mitogen-activated protein kinase (MAPK), and NF-κB, and RA treatments attenuated the activation of the three MAPKs and NF-κB. Moreover, cotreatment with RA and Erk, JNK, p38 MAPK, or NF-κB inhibitors further downregulated the mRNA expression of TNFα, IL-8, and iNOS, and decreased the production of TNFα, IL-8, and NO by A7r5 cells. Taken together, these findings indicate that RA may ameliorate the LPS-provoked inflammatory response of vascular smooth muscle cells by inhibition of MAPK/NF-κB signaling.

Corosolic Acid Attenuates the Invasiveness of Glioblastoma Cells by Promoting CHIP-Mediated AXL Degradation and Inhibiting GAS6/AXL/JAK Axis.

Corosolic acid (CA), a bioactive compound obtained from Actinidia chinensis, has potential anti-cancer activities. Glioblastoma (GBM) is a malignant brain tumor and whether CA exerts anti-cancer activity on GBM remains unclear. This study was aimed to explore the anticancer activity and its underlying mechanism of CA in GBM cells. Our findings showed that CA ≤ 20 µM did not affect cell viability and cell proliferative rate of normal astrocyte and four GBM cells. Notably, 10 or 20 µM CA significantly inhibited cell migration and invasion of three GBM cells, decreased the protein level of F-actin and disrupted F-actin polymerization in these GBM cells. Further investigation revealed that CA decreased AXL level by promoting ubiquitin-mediated proteasome degradation and upregulating the carboxyl terminus of Hsc70-interacting protein (CHIP), an inducer of AXL polyubiquitination. CHIP knock-down restored the CA-reduced AXL and invasiveness of GBM cells. Additionally, we observed that CA-reduced Growth arrest-specific protein 6 (GAS6) and inhibited JAK2/MEK/ERK activation, and GAS6 pre-treatment restored attenuated JAK2/MEK/ERK activation and invasiveness of GBM cells. Furthermore, molecular docking analysis revealed that CA might bind to GAS6 and AXL. These findings collectively indicate that CA attenuates the invasiveness of GBM cells, attributing to CHIP upregulation and binding to GAS6 and AXL and subsequently promoting AXL degradation and downregulating GAS6-mediated JAK2/MEK/ERK cascade. Conclusively, this suggests that CA has potential anti-metastatic activity on GBM cells by targeting the CHIP/GAS6/AXL axis.

Adenine Inhibits the Invasive Potential of DLD-1 Human Colorectal Cancer Cell via the AMPK/FAK Axis.

Tumor metastasis is a major cause of death of patients with colorectal cancer (CRC). Our previous findings show that adenine has antiproliferation activity against tumor cells. However, whether adenine reduces the invasiveness of DLD-1 and SW480 CRC cells has not been thoroughly explored. In this study, we aimed to explore the effects of adenine on the invasion potential of DLD-1 cells. Our findings showed that adenine at concentrations of ≤200 µM did not influence the cell viability of DLD-1 and SW480 CRC cells. By contrast, adenine reduced the migratory potential of the CRC cells. Moreover, it decreased the invasion capacity of the CRC cells in a dose-dependent manner. We further observed that adenine downregulated the protein levels of tissue plasminogen activator, matrix metalloproteinase-9, Snail, TWIST, and vimentin, but upregulated the tissue inhibitor of metalloproteinase-1 expression in DLD-1 cells. Adenine decreased the integrin αV level and reduced the activation of integrin-associated signaling components, including focal adhesion kinase (FAK), paxillin, and Src in DLD-1 cells. Further observations showed that adenine induced AMP-activated protein kinase (AMPK) activation and inhibited mTOR phosphorylation in DLD-1 cells. The knockdown of AMPK restored the reduced integrin αV level and FAK/paxillin/Src signaling inhibited by adenine in DLD-1 cells. Collectively, these findings reveal that adenine reduces the invasion potential of DLD-1 cells through the AMPK/integrin/FAK axis, suggesting that adenine may have anti-metastatic potential in CRC cells.

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.

Aqueous Mulberry Leaf Extract Ameliorates Alcoholic Liver Injury Associating with Upregulation of Ethanol Metabolism and Suppression of Hepatic Lipogenesis.

Excessive alcohol intake is a major cause of chronic liver damage and is highly associated with the development of a spectrum of hepatic disorders, including steatohepatitis, liver cirrhosis, and liver cancer. Thus, we aimed to explore the hepatoprotective effects of an aqueous mulberry leaf extract (AME) on alcoholic fatty liver disorder (AFLD) by using a mouse model fed with excessive ethanol. Compared with the normal diet, the ethanol diet significantly increased the body weight of the mice, while the AME supplement reduced the weight gain caused by the ethanol diet. The ethanol diet also attenuated the activity of alcohol dehydrogenase and antioxidant enzymes but increased lipid peroxidation in the liver, which were reversed by AME supplementation. Additionally, AME supplementation diminished the ethanol diet-induced hepatic leukocyte infiltration and expressions of IL-6 and TNFα. Moreover, AME supplementation also reduced the ethanol-diet-induced lipid accumulation and expression of 1-acylglycerol-3-phosphate acyltransferase, acetyl-CoA carboxylase, low-density lipoprotein receptor, and sterol regulatory element-binding protein-1/2 in the liver. Collectively, AME supplementation improved liver lipid accumulation and proinflammatory response in mice induced by the ethanol diet, which was associated with the upregulation of ethanol-metabolizing enzymes and the downregulation of lipogenesis components.

BCL-6 promotes the methylation of miR-34a by recruiting EZH2 and upregulating CTRP9 to protect ischemic myocardial injury.

Acute myocardial infarction (AMI) and the following heart failure are public health problems faced all over the globe. The current study set out to investigate the role of B-cell lymphoma 6 (BCL-6) in cardiac protection after AMI. Initially, AMI mouse models and H9c2 cell oxygen-glucose deprivation (OGD) models were established. The cell models were transfected with the vectors containing oe-BCL-6, oe-EZH2, sh-EZH2, miR-34a mimic, and miR-34a inhibitor. RT-qPCR and Western blot analysis were applied to detect the expression patterns of microRNA-34a (miR-34a), BCL-6, enhancer of zeste homolog 2 (EZH2), and C1q tumor necrosis factor-related protein 9 (CTRP9) in the treated cell models. ChIP-qPCR and co-immunoprecipitation assay were performed to detect EZH2 enrichment and H3K27me3 levels in the miR-34a promoter region and the interaction between BCL-2 and EZH2, respectively. EdU staining, TUNEL staining, and flow cytometry were performed to detect cell proliferation and apoptosis, while ELISA was conducted to detect the oxidative stress levels. It was found that miR-34a was highly expressed in heart tissues of AMI models, while BCL-6 and EZH2 were poorly expressed. BCL-2 overexpression increased the recruitment of EZH2, upregulated H3K27me3 level in the miR-34a promoter region, and inhibited the miR-34a expression. Ctrp9, the downstream negative-regulatory molecule of miR-34a, was upregulated. Besides, miR-34a/CTRP9 expression changes were found to affect cardiomyocyte apoptosis, oxidation stress, and proliferation, and prevent myocardial injury in AMI mice. Our findings indicate that BCL-6 increases the level of H3K27me3 in the promoter region of miR-34a via EZH2 recruitment and CTRP9 upregulation, which inhibits the apoptosis of myocardial cells.

Gossypol Reduces Metastasis and Epithelial-Mesenchymal Transition by Targeting Protease in Human Cervical Cancer.

Metastasis is the most prevalent cause of cancer-associated deaths amongst patients with cervical cancer. Epithelial-mesenchymal transition (EMT) is essential for carcinogenesis, and it confers metastatic properties to cancer cells. Gossypol is a natural polyphenolic compound with anti-inflammation, anti-oxidant, and anticancer activities. In this study, we investigated the antimetastatic and antitumour effects of gossypol on human cervical cancer cells (HeLa and SiHa cells). Gossypol exerted a strong inhibition effect on the migration and invasion of human cervical cancer cells. It reduced the focal adhesion kinase (FAK) pathway-mediated expression of matrix metalloproteinase-2 and urokinase-type plasminogen activator, subsequently inhibiting the invasion of SiHa cells. In addition, gossypol reversed EMT induced by transforming growth factor beta 1 (TGF-[Formula: see text]1) and up-regulated epithelial markers, such as E-cadherin but significantly suppressed Ras homolog family member (Rho)A, RhoB, and p-Samd3. The tail vein injection model showed that gossypol treatment via oral gavage reduced lung metastasis. Gossypol also decreased tumour growth in vivo in the nude mouse xenograft model. All these findings suggest that gossypol suppressed the invasion and migration of human cervical cancer cells by targeting the FAK signaling pathway and reversing TGF-[Formula: see text]1-induced EMT. Hence, gossypol warrants further attention for basic mechanistic studies and drug development.

Sesamin inhibits cervical cancer cell proliferation by promoting p53/PTEN-mediated apoptosis.

Background: Sesamin is a major bioactive compound in sesame seeds and has various biological properties, including anti-inflammatory and anticancer activities. Here, we explored whether sesamin activates p53, which is widely inhibited in cervical cancer cells, thereby inducing p53-mediated apoptosis. Methods: Human HeLa and SiHa cervical cancer cells and normal Hs68 dermal cells were used as cell models. Cell proliferation, cell cycle distribution, and apoptosis were evaluated by the CCK-8 assay and flow cytometry using PI/Annexin V staining, respectively. Protein expression and phosphorylation were determined using western blotting. The involvement of p53 in the apoptotic cascade was assessed by a specific inhibitor. Results: Sesamin (75 and 150 µM) clearly inhibited SiHa and HeLa cell proliferation in a dose-dependent fashion, but did not affect the proliferation of Hs68 cells. Meanwhile, sesamin increased the sub-G1 phase ratio and apoptosis, up to approximately 38.5% and 37.8%, respectively. Furthermore, sesamin induced p53 phosphorylation at serine-46 and serine-15 and upregulated the levels of PUMA, Bax, and PTEN, while inhibiting AKT phosphorylation at serine-473. Inhibition of p53 by pifithrin-α significantly reduced the levels of PUMA, Bax, and PTEN but restored AKT phosphorylation in SiHa cells exposed to sesamin. Pifithrin-α also reduced apoptosis and restored the proliferation of HeLa and SiHa cells exposed to sesamin. Conclusions: These findings indicate that sesamin inhibits cervical cancer cell proliferation, and its mechanism may be attributed to the induction of p53/PTEN-mediated apoptosis. This suggests that sesamin might be useful as an adjuvant in promoting anti-cervical cancer treatments.

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.

Adenine inhibits growth of hepatocellular carcinoma cells via AMPK-mediated S phase arrest and apoptotic cascade.

Background: Adenine exhibits potential anticancer activity against several types of malignancies. However, whether adenine has anticancer effects on hepatocellular carcinoma (HCC) cells is incompletely explored. Methods: Human HCC cell lines HepG2 and SK-Hep-1 (p53-wild type) and Hep3B (p53-deficient) were used as cell model. Cell growth and cell cycle distribution were determined using MTT assay and flow cytometric analysis, respectively. Protein expression and phosphorylation were assessed by Western blot. Involvement of AMP-activated protein kinase (AMPK) was evaluated using specific inhibitor and small inhibitory RNA (siRNA). Results: Adenine treatments (0.5 - 2 mM) clearly decreased the cell growth of Hep G2 and SK-Hep-1 cells to 72.5 ± 3.4% and 71.3 ± 4.6% of control, respectively. In parallel, adenine also induced sub-G1 and S phase accumulation in both HCC cells. However, adenine did not affect the cell growth and cell cycle distribution of Hep3B cell. Western blot analysis showed that adenine reduced expression of cyclin A/D1 and cyclin-dependent kinase (CDK)2 and upregulated p53, p21, Bax, PUMA, and NOXA in HepG2 cell. Moreover, adenine induced AMPK activation that was involved in the p53-associated apoptotic cascade in HepG2 cells. Inhibition of AMPK activation or knockdown of AMPK restored the decreased cell growth of HepG2 and SK-Hep-1 cells in response to adenine. Conclusions: These findings reveal that adenine reduces the cell growth of HepG2 and SK-Hep-1 but not Hep3B cells, attributing to the AMPK/p53-mediated S phase arrest and apoptosis. It suggests that adenine has anticancer potential against p53-wild type HCC cells and may be beneficial as an adjuvant for HCC treatment.

Imiquimod Exerts Antitumor Effects by Inducing Immunogenic Cell Death and Is Enhanced by the Glycolytic Inhibitor 2-Deoxyglucose.

The induction of immunogenic cell death (ICD) in cancer cells triggers specific immune responses against the same cancer cells. Imiquimod (IMQ) is a synthetic ligand of toll-like receptor 7 that exerts antitumor activity by stimulating cell-mediated immunity or by directly inducing apoptosis. Whether IMQ causes tumors to undergo ICD and elicits a specific antitumor immune response is unknown. We demonstrated that IMQ-induced ICD-associated features, including the surface exposure of calreticulin and the secretion of adenosine triphosphate and HMGB1, were mediated by ROS and endoplasmic reticulum stress. In a B16F10 melanoma mouse model, vaccinating mice with IMQ-induced ICD cell lysate or directly injecting IMQ in situ reduced tumor growth that was mediated by inducing tumor-specific T-cell proliferation, promoting tumor-specific cytotoxic killing by CD8+ T cells, and increasing the infiltration of various immune cells into tumor lesions. The ICD-associated features were crucial in the induction of specific antitumor immunity in vivo. The glycolytic inhibitor 2-deoxyglucose enhanced IMQ-induced ICD-associated features and strengthened the antitumor immunity mediated by IMQ-induced ICD cell lysate in p53-mutant cancer cells, which were IMQ-resistant in vitro. We conclude that IMQ is an authentic ICD inducer and provide a concept connecting IMQ-induced cancer cell death and antitumor immune responses.

α-Mangostin attenuates stemness and enhances cisplatin-induced cell death in cervical cancer stem-like cells through induction of mitochondrial-mediated apoptosis.

Cancer stem cells (CSCs) exhibit specific characteristics including decontrolled self-renewal, tumor-initiating, promoting, and metastatic potential, abnormal stemness signaling, and chemotherapy resistance. Thus, targeting CSC is becoming an emerging cancer treatment. α-Mangostin has been shown to have potent and multiple anticancer activities. Accordingly, we hypothesized that α-mangostin may diminish the stemness and proliferation of CSC-like cervical cancer cells. In our results, comparing to the parent cells, CSC-like SiHa and HeLa cells highly expressed CSC marker Sox2, Oct4, Nanog, CK-17, and CD49f. α-Mangostin significantly reduced the cell viability, sphere-forming ability, and expression of the CSC stemness makers of CSC-like cervical cancer cells. Further investigation showed that α-mangostin induced mitochondrial depolarization and mitochondrial apoptosis signaling, including upregulation of Bax, downregulation of Mcl-1 and Bcl-2, and activation of caspase-9/3. Moreover, α-mangostin synergically enhanced the cytotoxicity of cisplatin on CSC-like SiHa cells by promoting mitochondrial apoptosis and inhibiting the expression of CSC markers. Consistent with in vitro findings, in vivo tumor growth assay revealed that α-mangostin administration significantly inhibited the growth of inoculated CSC-like SiHa cells and synergically enhanced the antitumor effect of cisplatin. Our findings indicate that α-mangostin can reduce the stemness and proliferation of CSC-like SiHa and HeLa cells and promote the cytotoxicity of cisplatin, which may attribute to the mitochondrial apoptosis activation. Thus, it suggests that α-mangostin may have clinical potential to improve chemotherapy for cervical cancer by targeting cervical CSC.

Dietary delphinidin inhibits human colorectal cancer metastasis associating with upregulation of miR-204-3p and suppression of the integrin/FAK axis.

Delphinidin is a flavonoid belonging to dietary anthocyanidin family that has been reported to possess diverse anti-tumoral activities. However, the effects of delphinidin on colorectal cancer (CRC) cells and the underlying mechanisms are not fully understood. Thus, we aimed to investigate the anti-cancer activity of delphinidin in CRC cells and the underlying molecular mechanisms. The effects of delphinidin on the viability, metastatic characteristics, signaling, and microRNA (miR) profile of human CRC cell lines used were analyzed. In vivo metastasis was also evaluated using xenograft animal models. Our findings showed that delphinidin (<100 µM) inhibited the colony formation of DLD-1, SW480, and SW620 cells, but non-significantly affected cell viability. Delphinidin also suppressed the migratory ability and invasiveness of the tested CRC cell lines, downregulated integrin αV/ß3 expression, inhibited focal adhesion kinase (FAK)/Src/paxillin signaling, and interfered with cytoskeletal construction. Analysis of the miR expression profile revealed a number of miRs, particularly miR-204-3p, that were significantly upregulated and downregulated by delphinidin. Abolishing the expression of one upregulated miR, miR-204-3p, with an antagomir restored delphinidin-mediated inhibition of cell migration and invasiveness in DLD-1 cells as well as the αV/ß3-integrin/FAK/Src axis. Delphinidin also inhibited the lung metastasis of DLD-1 cells in the xenograft animal model. Collectively, these results indicate that the migration and invasion of CRC cells are inhibited by delphinidin, and the mechanism may involve the upregulation of miR-204-3p and consequent suppression of the αV/ß3-integrin/FAK axis. These findings suggest that delphinidin exerts anti-metastatic effects in CRC cells by inhibiting integrin/FAK signaling and indicate that miR-204-3p may play an important role in CRC metastasis.