Discovery of the tryptanthrin-derived indoloquinazoline as an anti-breast cancer agent via ERK/JNK activation

Tryptanthrin, an alkaloid applied in traditional Chinese medicine, exhibits a variety of pharmacological activities. This study aimed to investigate the anti-tumor activity of the tryptanthrin derivative (8-cyanoindolo[2,1-b]quinazoline-6,12-dione [CIQ]) in breast cancer cells. In both MDA-MB-231 and MCF-7 breast cancer cells, CIQ inhibited cell viability and promoted caspase-dependent apoptosis. At the concentration- and time-dependent ways, CIQ increased the levels of p-ERK, p-JNK, and p-p38 in breast cancer cells. We found that exposure to the JNK inhibitor or the ERK inhibitor partially reversed CIQ's viability. We also observed that CIQ increased reactive oxygen species (ROS) generation, and upregulated the phosphorylation and expression of H2AX. However, the pretreatment of the antioxidants did not protect the cells against CIQ's effects on cell viability and apoptosis, which suggested that ROS does not play a major role in the mechanism of action of CIQ. In addition, CIQ inhibited the invasion of MDA-MB-231 cells and decreased the expression of the prometastatic factors (MMP-2 and Snail). These findings demonstrated that the possibility of this compound to show promise in playing an important role against breast cancer.

Molecularly imprinted dispersive micro solid-phase extraction and tandem derivatization for the determination of histamine in fermented wines

Histamine causes allergic reactions and can serve as an indicator for assessing food quality. This study designed and developed a dispersive micro solid-phase extraction (D-μSPE) method that combined the advantages of dispersive liquid-liquid extraction and solid-phase extraction (SPE). Molecularly imprinted polymers (MIPs) were employed as the solid phase in the D-μSPE method to extract histamine in wine samples. We used microwave energy to significantly reduce the synthesis time, achieving an 11.1-fold shorter synthesis time compared to the conventional MIP synthetic method. Under optimized D-μSPE conditions, our results showed that the dispersive solvent could effectively increase the adsorption performance of MIPs in wine samples by 97.7%. To improve the sensitivity of histamine detection in gas chromatography-mass spectrometry, we employed the microwave-assisted tandem derivatization method to reuse excess derivatization reagents and reduce energy consumption and reaction time. Calibration curves were constructed for wine samples spiked with 0-400 nmol histamine using the standard addition method, resulting in good linearity with a coefficient of determination of 0.999. The intra- and inter-batch relative standard deviations of the slope and intercept were < 0.7% and < 5.3%, respectively. The limits of quantitation and detection were 0.4 nmol and 0.1 nmol, respectively. The developed method was successfully applied to analyze the histamine concentration in 10 commercial wine samples. In addition, the AGREEprep tool was used to evaluate the greenness performance of the developed method, which obtained a higher score than the other reported methods.

A PKM2 inhibitor induces apoptosis and autophagy through JAK2 in human oral squamous cell carcinoma cells

The enzyme pyruvate kinase M2 (PKM2) is involved in glycolysis, which plays an important role in the regulation of tumor progression. In this study, we investigated the anti-tumor activity of N-(4-(3-(3-(methylamino)-3-oxopropyl)-5-(4'-(prop-2-yn-1-yloxy)-[1,1'-biphenyl]-4-yl)-1H-pyrazol-1-yl)phenyl)propiolamide (MTP), a PKM2 inhibitor, in oral squamous cell carcinoma (OSCC) cells. Our results showed that MTP inhibited cell growth with IC50 values of 0.59 μM and 0.78 μM in SCC2095 and HSC3 OSCC cells, respectively. MTP induced caspase-dependent apoptosis, which was associated with the modulation of PKM2 and oncogenic biomarkers epidermal growth factor receptor and β-catenin. In addition, MTP increased the generation of reactive oxygen species (ROS) and modulated the expression of autophagic gene products, including LC3B-II and p62. Western blotting showed that MTP inhibited Janus kinase 2 (JAK2) signaling, and JAK2 overexpression partially reversed MTP-mediated cytotoxicity. Taken together, these data indicate the potential use of MTP as a therapeutic agent for OSCC.

Extract of Ficus septica modulates apoptosis and migration in human oral squamous cell carcinoma cells

According to the alarming statistical analysis of global cancer, there are over 19 million new diagnoses and more than 10 million deaths each year. One such cancer is the oral squamous cell carcinoma (OSCC), which requires new therapeutic strategies. Ficus septica extract has been used in traditional medicine to treat infectious diseases. In this study, we examined the anti-proliferative effects of an extract of F. septica bark (FSB) in OSCC cells. Our results showed that FSB caused a concentration-dependent reduction in the viability of SCC2095 OSCC cells, as determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assays, and was less sensitive to fibroblasts. In addition, FSB induced apoptosis by activating caspases, accompanied by the modulation of Akt/mTOR/NF-κB and mitogen-activated protein kinase signaling. Moreover, FSB increased reactive oxygen species generation in a concentration-dependent manner in SCC2095 cells. Furthermore, FSB inhibited cell migration and modulated the levels of the cell adhesion molecules including E-cadherin, N-cadherin, and Snail in SCC2095 cells. Pinoresinol, a lignan isolated from FSB, showed antitumor effects in SCC2095 cells, implying that this compound might play an important role in FSB-induced OSCC cell death. Taken together, FSB is a potential anti-tumor agent against OSCC cells.

Fructose milieu undermines the therapeutic effect of Tribulus terrestris extract on neuroblastoma cell line via maintaining mitochondrial function

Fructose overconsumption promotes tumor progression. Neuroblastoma is a common extracranial tumor with about 50% 5-year survival rate in high-risk children. The anti-tumor effect of Tribulus terrestris might bring new hope to neuroblastoma therapy. However, whether fructose disturbs the therapeutic effect of T. terrestris is currently unknown. In this study, the mouse neuroblastoma cell line, Neuro 2a (N2a) cells, was used to investigate the therapeutic effects of T. terrestris extract at various dosages (0.01, 1, 100 ng/ml) in regular EMEM medium or extra added fructose (20 mM) for 24 h. 100 ng/ml T. terrestris treatment significantly reduced the cell viability, whereas the cell viabilities were enhanced at the dosages of 0.01 or 1 ng/ml T. terrestris in the fructose milieu instead. The inhibition effect of T. terrestris on N2a migration was blunted in the fructose milieu. Moreover, T. terrestris effectively suppressed mitochondrial functions, including oxygen consumption rates, the activities of electron transport enzymes, the expressions of mitochondrial respiratory enzymes, and mitochondrial membrane potential. These suppressions were reversed in the fructose group. In addition, the T. terrestris-suppressed mitofusin and the T. terrestris-enhance mitochondrial fission 1 protein were maintained at basal levels in the fructose milieu. Together, these results demonstrated that T. terrestris extract effectively suppressed the survival and migration of neuroblastoma via inhibiting mitochondrial oxidative phosphorylation and disturbing mitochondrial dynamics. Whereas, the fructose milieu blunted the therapeutic effect of T. terrestris, particularly, when the dosage is reduced.

Targeting Triple Negative Breast Cancer Stem Cells by Heat Shock Protein 70 Inhibitors

Simple Summary

Triple negative breast cancer (TNBC) has been a leading cause of cancer deaths among women and limited treatment options are currently available. Consequently, developing the promising therapy for TNBC remains an unmet medical need. The aim of this study was to assess the effect of Hsp70 inhibitors on breast cancer stem cells (BCSCs) in TNBC cells. The present study demonstrated the potent in vitro and in vivo anti-BCSCs activity of two Hsp70 inhibitors, compound 1 and 6, in TNBC cells. Our findings suggest that targeting Hsp70 could be an attractive strategy for eliminating BCSCs populations in TNBC.

Abstract

Triple negative breast cancer (TNBC) is considered the most aggressive breast cancer with high relapse rates and poor prognosis. Although great advances in the development of cancer therapy have been witnessed over the past decade, the treatment options for TNBC remain limited. In this study, we investigated the effect and potential underlying mechanism of the Hsp70 inhibitors, compound 1 and compound 6, on breast cancer stem cells (BCSCs) in TNBC cells. Our results showed that compound 1 and 6 exhibited potent tumor suppressive effects on cell viability and proliferation, and effectively inhibited BCSC expansion in TNBC cells. Reminiscent with the effect of Hsp70 inhibitors, Hsp70 knockdown effectively suppressed mammosphere formation and the expressions of BCSCs surface markers. Mechanistically, evidence showed that the Hsp70 inhibitors inhibited BCSCs by down-regulating β-catenin in TNBC cells. Moreover, we used the Hsp70 inhibitors treated TNBC cells and a stable Hsp70 knockdown clone of MDA-MB-231 cells to demonstrate the in vivo efficacy of Hsp70 inhibition in suppressing tumorigenesis and xenograft tumor growth. Together, these findings suggest the potential role of Hsp70 as a target for TNBC therapy and foster new therapeutic strategies to eliminate BCSCs by targeting Hsp70.

Rapid methylation of valsartan in human plasma using evaporative derivatization reagent to improve its sensitivity in MALDI-TOF mass spectrometry

Matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) is a rapid and low-solvent-consumption technique. However, almost every mass in the low mass-to-charge-ratio region of the mass spectrum appears as strongly fluctuating matrix background signals. Thus, it is difficult to identify small molecules using this technique. In this study, we used methanol to methylate valsartan, an angiotensin II receptor blocker that is commonly used to treat high blood pressure and heart failure. The methylation derivatization of valsartan enhanced the detection sensitivity and transformed the detection m/z ratio. The liquid-phase microextraction of valsartan in human plasma (20 μL) was achieved by acidifying valsartan with HCl aqueous solution and extracting it with toluene. An acetyl chloride/anhydrous methanol mixture was added for methylation derivatization, which was completed within 30 min at 30 °C. Finally, the residue was re-dissolved in irbesartan methanolic solution, which together with the matrix 2-mercaptobenzothiazole was spotted on an AnchorChip target plate for MALDI-TOF MS analysis. Liquid-phase microextraction was performed and the methylation-derivatization parameters were investigated. The valsartan calibration range was 0.2-10 μg mL^-1 with good linearity in human plasma. In the within- and between-run analyses, the relative standard deviation and relative error were both <11.32%. This method was successfully applied to determine the valsartan concentration in the plasma of 10 patients with hypertension.

Induction of apoptosis using ATN as a novel Yes-associated protein inhibitor in human oral squamous cell carcinoma cells

Oral squamous cell carcinoma (OSCC) represents a clinical challenge due to the lack of effective therapy to improve prognosis. Hippo/Yes-associated protein (YAP) signaling has emerged as a promising therapeutic target for squamous cell carcinoma treatment. In this study, we investigated the antitumor activity and underlying mechanisms of {[N-(4-(5-(3-(3-(4-acetamido-3-(trifluoromethyl)phenyl)ureido)phenyl)-1,2,4-oxadiazol-3-yl)-3-chlorophenyl)-nicotinamide]} (ATN), a novel YAP inhibitor, in OSCC cells. ATN exhibited differential antiproliferative efficacy against OSCC cells (IC₅₀ as low as 0.29 μM) versus nontumorigenic human fibroblast cells (IC₅₀  = 1.9 μM). Moreover, ATN effectively suppressed the expression of YAP and YAP-related or downstream targets, including Akt, p-AMPK, c-Myc, and cyclin D1, which paralleled the antiproliferative efficacy of ATN. Supporting the roles of YAP in regulating cancer cell survival and migration, ATN not only induced caspase-dependent apoptosis, but also suppressed migration activity in OSCC. Mechanistically, the antitumor activity of ATN in OSCC was attributed, in part, to its ability to regulate Mcl-1 expression. Together, these findings suggest a translational potential of YAP inhibitors, represented by ATN as anticancer therapy for OSCC.

Kaempferol 3-Rhamnoside on Glutamate Release from Rat Cerebrocortical Nerve Terminals Involves P/Q-Type Ca2+ Channel and Ca2+/Calmodulin-Dependent Protein Kinase II-Dependent Pathway Suppression

Excess synaptic glutamate release has pathological consequences, and the inhibition of glutamate release is crucial for neuroprotection. Kaempferol 3-rhamnoside (KR) is a flavonoid isolated from Schima superba with neuroprotective properties, and its effecton the release of glutamate from rat cerebrocortical nerve terminals was investigated. KR produced a concentration-dependent inhibition of 4-aminopyridine (4-AP)-evoked glutamate release with half-maximal inhibitory concentration value of 17 µM. The inhibition of glutamate release by KR was completely abolished by the omission of external Ca²⁺ or the depletion of glutamate in synaptic vesicles, and it was unaffected by blocking carrier-mediated release. In addition, KR reduced the 4-AP-evoked increase in Ca²⁺ concentration, while it did not affect 4-AP-evoked membrane potential depolarization. The application of selective antagonists of voltage-dependent Ca²⁺ channels revealed that the KR-mediated inhibition of glutamate release involved the suppression of P/Q-type Ca²⁺ channel activity. Furthermore, the inhibition of release was abolished by the calmodulin antagonist, W7, and Ca²⁺/calmodulin-dependent protein kinase II (CaMKII) inhibitor, KN62, but not by the protein kinase A (PKA) inhibitor, H89, or the protein kinase C (PKC) inhibitor, GF109203X. We also found that KR reduced the 4-AP-induced increase in phosphorylation of CaMKII and its substrate synapsin I. Thus, the effect of KR on evoked glutamate release is likely linked to a decrease in P/Q-type Ca²⁺ channel activity, as well as to the consequent reduction in the CaMKII/synapsin I pathway.

A macrolide from Streptomyces sp. modulates apoptosis and autophagy through Mcl-1 downregulation in human breast cancer cells

Secondary metabolites in marine organisms exhibit various pharmacological activities against diseases, such as cancer. In this study, the anti-proliferative effect of JBIR-100, a macrolide isolated from Streptomyces sp., was investigated in breast cancer cells. Cell growth was inhibited in response to JBIR-100 treatment concentration- and time-dependently in both MCF-7 and MDA-MB-231 breast cancer cells. JBIR-100 caused apoptosis, as verified by caspase activation and the cleavage of PARP. Western blotting revealed that JBIR-100 modulated the expression of Akt/NF-κB signaling components and Bcl-2 family members. Overexpression of Mcl-1 partially rescued MCF-7 cells from JBIR-100-induced cytotoxicity. In addition, transmission electron microscopy analyses, confocal analysis, and western blot assay indicated that JBIR-100 inhibited autophagy in MCF-7 cells. Exposure to the autophagy inhibitor did not synergize JBIR-100-induced apoptosis. In summary, our results suggested that JBIR-100 may be potentially used for breast cancer therapy.

Tribulus terrestris fruit extract inhibits autophagic flux to diminish cell proliferation and metastatic characteristics of oral cancer cells

Elevated autophagy is highly associated with cancer development and progression. Fruit extracts of several plants inhibit activity of autophagy-related protease ATG4B and autophagy activity in colorectal cancer cells. However, the effects of these plant extracts in oral cancer cells remain unclear. In this study, we found that the extracted Tribulus terrestris fruit (TT-(fr)) and Xanthium strumarium fruit had inhibitory effects on autophagy inhibition in both SAS and TW2.6 oral cancer cells. Moreover, the fruit extracts had differential effects on cell proliferation of oral cancer cells. In addition, the fruit extracts hampered cell migration and invasion of oral cancer cells, particularly in TT-(fr) extracts. Our results indicated that TT-(fr) extracts consistently inhibited autophagic flux, cell growth and metastatic characteristics of oral cancer cells, suggesting TT-(fr) might contain function ingredient to suppress oral cancer cells.

New Hydroquinone Monoterpenoid and Cembranoid-Related Metabolites from the Soft Coral Sarcophyton tenuispiculatum

Chemical investigation of the marine soft coral Sarcophyton tenuispiculatum resulted in the isolation of a 1,4-dihydrobenzoquinone, sarcotenuhydroquinone (1), three new cembranoids, sarcotenusenes A‒C (2‒4), and ten previously reported metabolites 5–14. The chemical structures of all isolated metabolites were determined by detailed spectroscopic analyses. In biological assays, anti-inflammatory, cytotoxic, and peroxisome proliferator-activated receptor γ (PPAR-γ) transcription factor assays of all compounds were performed. None of the isolated compounds were found to exhibit activity in the PPAR-γ transcription factor assay. The anti-inflammatory assays showed that (+)-7α,8β-dihydroxydeepoxysarcophine (13) inhibited the production of IL-1β to 56 ± 1% at a concentration of 30 µM in lipopolysaccharide (LPS)-stimulated J774A.1 macrophage cells. In addition, 1 and 2 were found to exhibit cytotoxicity towards a panel of cancer cell lines.

[Application of carbon nanoparticles mapping lymph nodes in curative resection for colorectal carcinoma]

Objective: To investigate the clinical application of carbon nanoparticles mapping lymph nodes in curative resection for colorectal carcinoma. Methods: Patients diagnosed with colorectal cancer before operation and undergoing radical surgery with intact postoperative pathological data in the Sixth Affiliated Hospital, Sun Yat-sen University from March 2016 to March 2018 were included in this retrospective case-control study. Those who were diagnosed with ileus, recurrent carcinoma or underwent emergency operation were excluded. A total of 1421 cases were included, with 156 cases in the carbon nanoparticles mapping group and 1265 cases in the control group. Using 1∶3 case control matching based on gender, weight, TNM staging and neoadjuvant chemotherapy, 145 and 435 cases were finally recruited in the carbon nanoparticles mapping group and control group, respectively. Patients in the carbon nanoparticles mapping group underwent preoperative colonoscopy with carbon nanoparticles submucosal injection 2.4 (1.0 - 14.0) days before operation. Carbon nanoparticles of 0.25 ml was injected at 4 points (3, 6, 9 and 12 o'clock each) 0.5-1.0 cm around the tumor. The number of eliminated lymph node, number of positive lymph node and positive rate between the two groups were compared, and the number of eliminated lymph node in different subgroups of T stage, N stage, TNM stage and neoadjuvant chemotherapy was analyzed and compared. Results: After case control matching, total number of eliminated lymph nodes in the carbon nanoparticles mapping group was significantly higher than that in the control group (22.2±11.2 vs. 19.0±9.5, t=3.025, P=0.003). However, no statistically significant differences were found in the number of positive lymph node and lymph node positive rate between two groups (all P>0.05). Subgroup analysis showed that as compared to the control group, total number of eliminated lymph nodes in the carbon nanoparticles mapping group was significantly higher in T3 stage subgroup (median: 22 vs. 18, Z=2.435, P=0.015), N0 stage subgroup (median: 20.5 vs. 17.5, Z=2.772, P=0.006), TNM II stage subgroup (median: 23.5 vs. 19.0, Z=2.654, P=0.008) and neoadjuvant chemotherapy (median: 22.5 vs. 13.0, Z=3.287, P=0.001), while compared to the control group, the number of positive lymph node (median: 4.0 vs. 6.5, Z=-2.530, P=0.011) and the lymph node metastasis degree (median: 16% vs. 31%, Z=-2.862, P=0.004) were lower in the carbon nanoparticles mapping group in N2 subgroup. Conclusion: Carbon nanoparticles mapping lymph nodes can effectively enhance the number of eliminated lymph nodes in curative resection for colorectal cancer.

Antitumor Activity of the Cardiac Glycoside αlDiginoside by Modulating Mcl-1 in Human Oral Squamous Cell Carcinoma Cells

We recently isolated a cardiac glycoside (CG), αldiginoside, from an indigenous plant in Taiwan, which exhibits potent tumor-suppressive efficacy in oral squamous cell carcinoma (OSCC) cell lines (SCC2095 and SCC4, IC₅₀ < 0.2 µM; 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assays). Here, we report that αldiginoside caused Sphase arrest and apoptosis, through the inhibition of a series of signaling pathways, including those mediated by cyclin E, phospho-CDC25C (p-CDC25C), and janus kinase/signal transducer and activator of transcription (JAK/STAT)3. αldiginoside induced apoptosis, as indicated by caspase activation and poly (ADP-ribose) polymerase (PARP) cleavage. Equally important, αldiginoside reduced Mcl-1 expression through protein degradation, and overexpression of Mcl-1 partially protected SCC2095 cells from αldiginoside’s cytotoxicity. Taken together, these data suggest the translational potential of αldiginoside to foster new therapeutic strategies for OSCC treatment.

Induction of Apoptosis and Autophagy in Breast Cancer Cells by a Novel HDAC8 Inhibitor

Epigenetic therapy has been demonstrated to be a viable strategy for breast cancer treatment. In this study, we report the anti-tumor activity of a hydroxamate-based histone deacetylase (HDAC)8-selective inhibitor, HMC, in breast cancer cells. MTT assays showed that HMC inhibited cell viability of MCF-7 and MDA-MB-231 cells with IC₅₀ values of 7.7 μM and 9.5 μM, respectively. HMC induced caspase-dependent apoptosis in MCF-7 cells, which was associated with its ability to modulate a series of cell survival-related signaling effectors, including Akt, mTOR, Bax, Mcl-1, and Bcl-2. Additionally, HMC was capable of activating PPARγ, which was accompanied by reduced expression of PPARγ target gene products, such as cyclin D1 and CDK6. HMC increased the production of ROS in MCF-7 cells, which could be partially reversed by the cotreatment with a ROS scavenger (N-acetylcysteine or glutathione). Furthermore, HMC induced autophagy, as characterized by the formation of acidic vesicular organelles and autophagic biomarkers including LC3B-II and Atg5. Notably, pharmacological blockade of autophagy by 3-MA or CQ could attenuate HMC-induced apoptosis, suggesting that autophagy played a self-protective role in HMC-induced cell death. Together, these data suggest the translational potential of HMC to be developed into a potential therapeutic agent for breast cancer therapy.

Antiviral activity of Sambucus FormosanaNakai ethanol extract and related phenolic acid constituents against human coronavirus NL63

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Sambucus FormosanaNakai extract reduced cytopathicity and virus yield in HCoV-NL63-infected cells.

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Among phenolic acid constituents, caffeic acid, chlorogenic acid and gallic acid sustained the anti-HCoV-NL63 activity.

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Sambucus FormosanaNakai extract and caffeic acid concentration-dependently inhibited HCoV-NL63 attachment onto cells.

Human coronavirus NL63 (HCoV-NL63), one of the main circulating HCoVs worldwide, causes respiratory tract illnesses like runny nose, cough, bronchiolitis and pneumonia. Recently, a severe respiratory illness outbreak of HCoV-NL63 has been reported in a long-term care facility. Sambucus FormosanaNakai, a species of elderberry, is a traditional medicinal herb with anti-inflammatory and antiviral potential. The study investigated the antiviral activity of Sambucus FormosanaNakai stem ethanol extract and some phenolic acid constituents against HCoV-NL63. The extract was less cytotoxic and concentration-dependently increased anti-HCoV-NL63 activities, including cytopathicity, sub-G1 fraction, virus yield (IC50 = 1.17 μg/ml), plaque formation (IC50 = 4.67 μg/ml) and virus attachment (IC50 = 15.75 μg/ml). Among the phenolic acid constituents in Sambucus FormosanaNakai extract, caffeic acid, chlorogenic acid and gallic acid sustained the anti-HCoV-NL63 activity that was ranked in the following order of virus yield reduction: caffeic acid (IC₅₀ = 3.54 μM) > chlorogenic acid (IC₅₀ = 43.45 μM) > coumaric acid (IC₅₀ = 71.48 μM). Caffeic acid significantly inhibited the replication of HCoV-NL63 in a cell-type independent manner, and specifically blocked virus attachment (IC₅₀ = 8.1 μM). Therefore, the results revealed that Sambucus Formosana Nakai stem ethanol extract displayed the strong anti-HCoV-NL63 potential; caffeic acid could be the vital component with anti-HCoV-NL63 activity. The finding could be helpful for developing antivirals against HCoV-NL63.

Cutaneous delivery of [1-(4-chloro-3-nitrobenzenesulfonyl)-1H-indol-3-yl]-methanol, an indole-3-carbinol derivative, mitigates psoriasiform lesion by blocking MAPK/NF-κB/AP-1 activation

[1-(4-chloro-3-nitrobenzenesulfonyl)-1H-indol-3-yl]-methanol (CIM) has been used as a bioactive agent for inhibiting tumor growth and angiogenesis via mitogen-activated protein kinase (MAPK) and NF-κB blocking. The present work was undertaken to investigate the potential of CIM against psoriasis using imiquimod (IMQ)-stimulated psoriasis-like mouse and in vitro HaCaT keratinocytes as the models. We demonstrated that topical CIM treatment reduced IMQ-activated scaling, erythema, and barrier dysfunction. This compound also restrained the recruitment of neutrophils. The cytokines, including TNF-α, IL-1β, IL-6, and IL-17 in psoriasiform skin, can be attenuated to normal baseline by CIM. Topically applied CIM can be easily delivered into skin based on the affinity with stratum corneum (SC) ceramides. IMQ intervention increased the permeability by 3-fold as compared to healthy skin. CIM ameliorated psoriatic lesion without incurring overt signs of irritation. Both TNF-α and IMQ were employed as the stimulators to activate HaCaT for reciprocal elucidation of the mechanism of action. CIM inhibited the overexpression of IL-1β, IL-6, and IL-24 in HaCaT. CIM exerted anti-inflammatory activity by suppressing the phosphorylation of NF-κB and activator protein-1 (AP-1) through MAPK pathways. Our results indicate that CIM has potential as the antipsoriatic molecule. The detailed signaling pathways still need further investigation.

Ursolic acid induces apoptosis and autophagy in oral cancer cells

Oral squamous cell carcinoma (OSCC) is the fifth common cause of cancer mortality in Taiwan with high incidence and recurrence and needs new therapeutic strategies. In this study, ursolic acid (UA), a triterpenoid, was examined the antitumor potency in OSCC cells. Our results showed that UA inhibited the proliferation of OSCC cells in a dose- and time-dependent manner in both Ca922 and SCC2095 oral cancer cells. UA induced caspase-dependent apoptosis accompanied with the modulation of various biological biomarkers including downregulating Akt/mTOR/NF-κB signaling, ERK, and p38. In addition, UA inhibited angiogenesis as evidenced by abrogation of migration/invasion and blocking MMP-2 secretion in Ca922 cells. Interestingly, UA induced autophagy in OSCC cells, as manifested by LC3B-II conversion and increased p62 expression and accumulation of autophagosomes. Inhibition by autophagy inhibitor enhanced UA-mediated apoptosis in Ca922 cells. The experiment provides a rationale for using triterpenoid in the treatment of OSCC.

Design of Diarylheptanoid Derivatives as Dual Inhibitors Against Class IIa Histone Deacetylase and β-amyloid Aggregation

Alzheimer’s disease (AD) is a progressive neurodegenerative disorder with multiple etiologies. Beta-amyloid (Aβ) self-aggregation and overexpression of class IIa histone deacetylases (HDACs) are strongly implicated with AD pathogenesis. In this study, a series of novel diarylheptanoid derivatives were designed, synthesized and evaluated for use as dual Aβ self-aggregation and class IIa HDAC inhibitors. Among these compounds, 4j, 5c, and 5e displayed effective inhibitions for Aβ self-aggregation, HDAC5 activity and HDAC7 activity with IC₅₀ values of <10 μM. The compounds contain three common features: (1) a catechol or pyrogallol moiety, (2) a carbonyl linker and (3) an aromatic ring that can function as an HDAC cap and create hydrophobic interactions with Aβ_1-42. Furthermore, compounds 4j, 5c, and 5e showed no significant cytotoxicity to human neuroblastoma SH-SY5Y cells and also exhibited neuroprotective effect against H₂O₂-induced toxicity. Overall, these promising in vitro data highlighted compounds 4j, 5c, and 5e as lead compounds that are worthy for further investigation.

A New Flavone from the Leaves of Astronia formosana

A new flavone, 5,4′-dihydroxy-7,3′-dimethoxy-6,8-dimethylflavone (1), together with four known compounds, ursolic acid (2), β-sitosterol-β-D-glucoside (3), β-sitosterol (4) and lupeol (5) were isolated from the methanolic extract of the leaves of Astronia formosana. The structures were elucidated on the basis of physical and spectroscopic data analyses. Compound 1 showed the slight cytotoxicity against MCF-7, SCM-1, and SCC2095 cell lines with IC50 values of 29.3 ± 9.2, 20.5 ± 10.2, and 25.7 ± 2.9 μM, respectively.

OSU-A9 inhibits pancreatic cancer cell lines by modulating p38-JAK-STAT3 signaling

Pancreatic cancer is an aggressive malignancy that is the fourth leading cause of death worldwide. Since there is a dire need for novel and effective therapies to improve the poor survival rates of advanced pancreatic cancer patients, we analyzed the antitumor effects of OSU-A9, an indole-3-carbinol derivative, on pancreatic cancer cell lines in vitro and in vivo. OSU-A9 exhibited a stronger antitumor effect than gemcitabine on two pancreatic cancer cell lines, including gemcitabine-resistant PANC-1 cells. OSU-A9 treatment induced apoptosis, the down-regulation of Akt phosphorylation, up-regulation of p38 phosphorylation and decreased phosphorylation of JAK and STAT3. Cell migration and invasiveness assays showed that OSU-A9 reduced cancer cell aggressiveness and inhibited BxPC-3 xenograft growth in nude mice. These results suggest that OSU-A9 modulates the p38-JAK-STAT3 signaling module, thereby inducing cytotoxicity in pancreatic cancer cells. Continued evaluation of OSU-A9 as a potential therapeutic agent for pancreatic cancer thus appears warrented.

Cyclocommunol induces apoptosis in human oral squamous cell carcinoma partially through a Mcl-1-dependent mechanism

BACKGROUND

Crude extract of breadfruit has been reported to have antitumor activity against various cancer cell lines with unknown mechanism.

PURPOSE

This study aims to investigate the proapoptotic effect of cyclocommunol (CYC), a prenylflavonoid from breadfruit, in two oral squamous cell carcinoma (OSCC) cell lines, SCC2095 and Ca922.

METHODS

The antiproliferative effects of CYC were assessed by MTT assays and PI/annexin V analysis. SCC2095 cells were transiently transfected with Mcl-1 plasmid in overexpression experiment. Other methods used to investigate the mechanism of CYC included Western blotting, acridine orange staining and confocal microscopic visualization.

RESULTS

Our results showed that CYC suppressed the viability of SCC2095 and Ca922 with IC₅₀ values at 48 h of 4.2 and 5.0 µM, respectively. This decrease in viability occurred in a caspase-dependent apoptotic manner. In addition, CYC down-regulated the phosphorylation/expression of Akt/mTOR and Mcl-1, accompanied by reactive oxygen species generation, and autophagy induction. Notably, overexpression of Mcl-1 using Mcl-1-tag-myc partially rescued CYC-mediated caspase-3 activation, PARP cleavage, and cytotoxicity. In summary, our study demonstrated the proapoptotic activity of CYC on OSCC, partially through down-regulation of Mcl-1.

CONCLUSION

CYC from breadfruit has translational value as a proapoptotic agent for OSCC.

Identification of a Triterpenoid as a Novel PPARγ Activator Derived from Formosan Plants

Peroxisome proliferator-activated receptor γ (PPARγ), one of the transcription factors that regulate lipid metabolism and energy use in tumor cells, is a viable target for cancer therapy. In our search for potential PPARγ activator, extracts from five Formosan plants were tested. Among them, Momordica charantia L. showed the highest ability to activate PPARγ, which led us to identify its potential constituents. Among the seven compounds isolated from M. charantia, a triterpenoid, 5β,19-epoxy-19-methoxycucurbita-6,23-dien-3β,25-diol (compound 1), was identified as a PPARγ activator with an IC₅₀ of 10 μM in breast cancer MCF-7 cells. Flow cytometric analysis indicated that compound 1 induced G1 cell cycle arrest which might be attributable to the modulation of phosphorylation and expression of numerous key signaling effectors, including cyclin D1, CDK6, and p53. Notably, compound 1 downregulated the expression of histone deacetylase 1, leading to increased histone H3 acetylation. Taken together, these findings suggest that compound 1 may have therapeutic applications in cancer treatment through PPARγ activation. Copyright © 2017 John Wiley & Sons, Ltd.

Ficus septica plant extracts for treating Dengue virus in vitro

Dengue virus types 1-4 (DENV-1-4) are positive-strand RNA viruses with an envelope that belongs to the Flaviviridae. DENV infection threatens human health worldwide. However, other than supportive treatments, no specific therapy is available for the infection. In order to discover novel medicine against DENV, we tested 59 crude extracts, without cytotoxicity, from 23 plants in vitro; immunofluorescence assay revealed that the methanol extracts of fruit, heartwood, leaves and stem from Ficus septica Burm. f. had a promising anti-DENV-1 and DENV-2 effect. However, infection with the non-envelope picornavirus, Aichi virus, was not inhibited by treatment with F. septica extracts. F. septica may be a candidate antiviral drug against an enveloped virus such as DENV.

Anti-apoptotic activity of Japanese encephalitis virus NS5 protein in human medulloblastoma cells treated with interferon-β

BACKGROUND

Japanese encephalitis virus (JEV) non-structural protein 5 (NS5) exhibits type I interferon (IFN) antagonists, contributing to immune escape, and even inducing viral anti-apoptosis. This study investigated the anti-apoptotic mechanism of JEV NS5 protein on type I IFN-induced apoptosis of human medulloblastoma cells.

METHODS

Vector control and NS5-expressing cells were treated with IFN-β, and then harvested for analyzing apoptotic pathways with flow cytometry, Western blotting, subcellular localization, etc. RESULTS: Annexin V-FITC/PI staining indicated that IFN-β triggered apoptosis of human medulloblastoma cells, but JEV NS5 protein significantly inhibited IFN-β-induced apoptosis. Phage display technology and co-immunoprecipitation assay identified the anti-apoptotic protein Hsp70 as a NS5-interacting protein. In addition, Western blotting demonstrated that NS5 protein up-regulated the Hsp70 expression, and reduced IFN-β-induced phosphorylation of ERK2, p38 MAPK and STAT1. Hsp70 down-regulation by quercetin significantly recovered IFN-β-induced apoptosis of NS5-expressing cells, correlating with the increase in the phosphorylation of ERK2, p38 MAPK, and STAT1. Inhibiting the ATPase activity of Hsp70 by VER-155008 resulted in the elevated IFN-β-induced apoptosis in vector control and NS5-expressing cells.

CONCLUSIONS

The results indicated Hsp70 up-regulation by JEV NS5 not only involved in type I IFN antagonism, but also responded to the anti-apoptotic action of JEV NS5 protein through the blocking IFN-β-induced p38 MAPK/STAT1-mediated apoptosis.

A Flavone Constituent from Myoporum bontioides Induces M-Phase Cell Cycle Arrest of MCF-7 Breast Cancer Cells

Myoporum bontioides is a traditional medicinal plant in Asia with various biological activities, including anti-inflammatory and anti-bacterial characteristics. To identify the bioactive constituents from M. bontioides, a newly-identified flavone, 3,4'-dimethoxy-3',5,7-trihydroxyflavone (compound 1), along with eight known compounds, were investigated in human MCF-7 breast cancer, SCC4 oral cancer, and THP-1 monocytic leukemia cells. Among these compounds, compound 1 exhibited the strongest antiproliferative activity with half-maximal inhibitory concentration (IC₅₀) values ranging from 3.3 μM (MCF-7) to 8.6 μM (SCC4). Flow cytometric analysis indicated that compound 1 induced G2/M cell cycle arrest in MCF-7 cells. Mechanistic evidence suggests that the G2/M arrest could be attributable to compound 1's modulatory effects on the phosphorylation and expression of numerous key signaling effectors, including cell division cycle 2 (CDC2), CDC25C, and p53. Notably, compound 1 downregulated the expression of histone deacetylase 2 (HDAC2) and HDAC4, leading to increased histone H3 acetylation and p21 upregulation. Together, these findings suggest the translational potential of compound 1 as a breast cancer treatment.

T315 Decreases Acute Myeloid Leukemia Cell Viability through a Combination of Apoptosis Induction and Autophagic Cell Death

T315, an integrin-linked kinase (ILK) inhibitor, has been shown to suppress the proliferation of breast cancer, stomach cancer and chronic lymphocytic leukemia cells. Here we demonstrate that T315 decreases cell viability of acute myeloid leukemia (AML) cell lines (HL-60 and THP-1) and primary leukemia cells from AML patients in a dose-responsive manner. Normal human bone marrow cells are less sensitive than leukemia cells to T315. T315 down regulates protein kinase B (Akt) and p-Akt and induces caspase activation, poly-ADP-ribose polymerase (PARP) cleavage, apoptosis and autophagy through an ILK-independent manner. Interestingly, pretreatment with autophagy inhibitors rescues cells from apoptosis and concomitant PARP cleavage, which implicates a key role of autophagic cell death in T315-mediated cytotoxicity. T315 also demonstrates efficacy in vivo, suppressing the growth of THP-1 xenograft tumors in athymic nude mice when administered intraperitoneally. This study shows that autophagic cell death and apoptosis cooperatively contribute to the anticancer activity of T315 in AML cells. In conclusion, the complementary roles of apoptotic and autophagic cell death should be considered in the future assessment of the translational value of T315 in AML therapy.

Pharmacological exploitation of the phenothiazine antipsychotics to develop novel antitumor agents-A drug repurposing strategy

Phenothiazines (PTZs) have been used for the antipsychotic drugs for centuries. However, some of these PTZs have been reported to exhibit antitumor effects by targeting various signaling pathways in vitro and in vivo. Thus, this study was aimed at exploiting trifluoperazine, one of PTZs, to develop potent antitumor agents. This effort culminated in A4 [10-(3-(piperazin-1-yl)propyl)-2-(trifluoromethyl)-10H-phenothiazine] which exhibited multi-fold higher apoptosis-inducing activity than the parent compound in oral cancer cells. Compared to trifluoperazine, A4 demonstrated similar regulation on the phosphorylation or expression of multiple molecular targets including Akt, p38, and ERK. In addition, A4 induced autophagy, as evidenced by increased expression of the autophagy biomarkers LC3B-II and Atg5, and autophagosomes formation. The antitumor activity of A4 also related to production of reactive oxygen species and adenosine monophosphate-activated protein kinase. Importantly, the antitumor utility of A4 was extended in vivo as it, administrated at 10 and 20 mg/kg intraperitoneally, suppressed the growth of Ca922 xenograft tumors. In conclusion, the ability of A4 to target diverse aspects of cancer cell growth suggests its value in oral cancer therapy.

Anti-tumor Activities of Triterpenes from Syzygium kusukusense

In this study, we report the isolation from the stem of Syzygium kusukusense of five triterpenes, 2α-hydroxybetulinic acid (1), betulinic acid (2), platanic acid (3), ursolic acid (4), and hyptatic acid A (5). All were identified for the first time from this indigenous plant of Taiwan. Assessment of the cytotoxic activities of these compounds against a panel of human tumor cell lines, including MCF-7 breast, PC-3 prostate, and SCC2095 oral squamous cell cancers, revealed the high potency of compounds 1 (IC50, 5.7 – 7.6 μM) and, especially, 4 (IC50, 1.7 – 3.7 μM) in suppressing cell viability, which warrants further mechanistic investigations.

Anti-tumor activities of triterpenes from Syzygium kusukusense

In this study, we report the isolation from the stem of Syzygium kusukusense of five triterpenes, 2α-hydroxybetulinic acid (1), betulinic acid (2), platanic acid (3), ursolic acid (4), and hyptatic acid A (5). All were identified for the first time from this indigenous plant of Taiwan. Assessment of the cytotoxic activities of these compounds against a panel of human tumor cell lines, including MCF-7 breast, PC-3 prostate, and SCC2095 oral squamous cell cancers, revealed the high potency of compounds 1 (IC50, 5.7 - 7.6 μM) and, especially, 4 (IC50, 1.7 - 3.7 μM) in suppressing cell viability, which warrants further mechanistic investigations.

Lantabetulic acid derivatives induce G1 arrest and apoptosis in human prostate cancer cells

Ten new lantabetulic acid (1) derivatives 2-11 were synthesized and their cytotoxicities against human prostate cancer cells were evaluated. PC3 cells treated with 10 μM 8 exhibited the most potent G1 phase arrest. In addition, 10 μM 8 markedly decreased the levels of cyclin E and cdk2 and caused an increase in the p21 and p27 levels, while 20 μM 8 mainly led to cell death through the apoptotic pathway, which correlated with an increase in reactive oxygen species levels, decreased expression levels of Bcl-2 and caspase-8, the induction of mitochondrial changes, and decreased levels of cytochrome c in mitochondria. The dual action of 8 could provide a new approach for the development of chemotherapeutic drugs.

Cytotoxic constituents from Celastrus paniculatus induce apoptosis and autophagy in breast cancer cells

Celastrus paniculatus is a traditional medicinal plant with diverse pharmacological activities. To identify its bioactive constituents, three new β-dihydroagarofuranoid sesquiterpenes were isolated from the whole plant, of which the major constituent is (1α,2α,8β,9β)-1,8-bis(acetyloxy)-2,9-bis(benzoyloxy)-14-hydroxy-β-dihydroagarofuran. It was assessed for its antiproliferative activity, and it suppressed the viability of MCF-7 breast cancer cells with an IC50 of 17±1μM. This growth inhibition was, in part, attributable to apoptosis. Moreover, this drug treatment led to LC3B-II accumulation, indicative of autophagy. Western blot analysis established its ability to target a broad range of signaling effectors related to survival and cell cycle progression, including Akt, NF-κB, p53, and MAP kinases. In addition, flow cytometry analysis indicates increased reactive oxygen species production in response to this compound. Taken together, these findings suggest a pleiotropic mode of mechanism that underlies the antiproliferative activity of this compound in MCF-7 breast cancer cells.

OSU-A9, an indole-3-carbinol derivative, induces cytotoxicity in acute myeloid leukemia through reactive oxygen species-mediated apoptosis

Indole-3-carbinol (I3C) is a broadly targeted phytochemical shown to prevent carcinogenesis in animal studies and to suppress the proliferation of cancer cells of human breast, colon, prostate, and endometrium. Here we demonstrate that OSU-A9, an I3C derivative with improved anticancer potency, induces cytotoxicity in acute myeloid leukemia (AML) cell lines (HL-60 and THP-1) and primary leukemia cells from AML patients in a dose-responsive manner. Normal human bone marrow cells were less sensitive to OSU-A9 than leukemia cells. OSU-A9 induces caspase activation, PARP cleavage, and autophagy but not autophagic cell death. Interestingly, pretreatment of AML cell lines and primary AML cells with N-acetylcysteine or glutathione rescues them from apoptosis (and concomitant PARP cleavage) and Akt hypophosphorylation, implicating a key role of reactive oxygen species (ROS) in OSU-A9-related cytotoxicity. Importantly, the anticancer utility of OSU-A9 is extended in vivo as it, administered intraperitoneally, suppresses the growth of THP-1 xenograft tumors in athymic nude mice without obvious toxicity. This study shows that ROS-mediated apoptosis contributes to the anticancer activity of OSU-A9 in AML cell lines and primary AML cells, and thus should be considered in the future assessment of its translational value in AML therapy.