Chrysanthemum boreale is a plant widespread in East Asia, used in folk medicine to treat various disorders, such as pneumonia, colitis, stomatitis, and carbuncle. Whether the essential oil from C. boreale (ECB) and its active constituents have anti-proliferative activities in lung cancer is unknown. Therefore, we investigated the cytotoxic effects of ECB in A549 and NCI-H358 human lung cancer cells. Culture of A549 and NCI-H358 cells with ECB induced apoptotic cell death, as revealed by an increase in annexin V staining. ECB treatment reduced mitochondrial membrane potential (MMP), disrupted the balance between pro-apoptotic and anti-apoptotic Bcl-2 proteins, and activated caspase-8, -9, and -3, as assessed by western blot analysis. Interestingly, pretreatment with a broad-spectrum caspase inhibitor (z-VAD-fmk) significantly attenuated ECB-induced apoptosis. Furthermore, gas chromatography–mass spectrometry (GC/MS) analysis of ECB identified six compounds. Among them, β-caryophyllene exhibited a potent anti-proliferative effect, and thus was identified as the major active compound. β- Caryophyllene induced G1 cell cycle arrest by downregulating cyclin D1, cyclin E, cyclin-dependent protein kinase (CDK) -2, -4, and -6, and RB phosphorylation, and by upregulating p21CIP1/WAF1 and p27KIP1. These results indicate that β-caryophyllene exerts cytotoxic activity in lung cancer cells through induction of cell cycle arrest.
Persea americana Mill, cv. Hass, also known as avocado, has been reported to possess hypolipidemic, anti-diabetic, anti-oxidant, cardioprotective, and photoprotective potencies. However, few studies have reported its anti-colitic effects. In this study, we investigated anti-colitic effects of ethanol extract of P. americana (EEP) in dextran sulfate sodium (DSS)-induced colitic mice and the involved molecular mechanisms. EEP effectively improved clinical signs and histological characteristics of DSS-induced colitis mice. In DSS-exposed colonic tissues, EEP reduced expression levels of inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), and pro-inflammatory cytokines such as interleukin (IL)-6, IL-1β, and tumor necrosis factor (TNF)-α. Moreover, EEP suppressed DSS-induced activation of nuclear factor-kappa B (NF-κB) and signal transducer and activator of transcription 3 (STAT3). Consistent with in vivo results, EEP also suppressed protein and mRNA expression levels of iNOS, COX-2, and pro-inflammatory cytokines via NF-κB and STAT3 inactivation in LPS-induced RAW 264.7 macrophages. Taken together, our data indicate that ethanol extract of avocado may be used as a promising therapeutic against inflammatory bowel diseases by suppressing the NF-κB and STAT3 signaling pathway.
We previously reported the potential anti-proliferative activity of 3-(5,6,7-trimethoxy-4-oxo-4H-chromen-2-yl)-N-(3,4,5-trimethoxyphenyl) benzamide (TMS-TMF-4f) against human cancer cells; however, the underlying molecular mechanisms have not been investigated. In the present study, TMS-TMF-4f showed the highest cytotoxicity in human cervical cancer cells (HeLa and CaSki) and low cytotoxicity in normal ovarian epithelial cells. Annexin V-FITC and propidium iodide (PI) double staining revealed that TMS-TMF-4f-induced cytotoxicity was caused by the induction of apoptosis in both HeLa and CaSki cervical cancer cells. The compound TMS-TMF-4f enhanced the activation of caspase-3, caspase-8, and caspase-9 and regulated Bcl-2 family proteins, which led to mitochondrial membrane potential (MMP) loss and resulted in the release of cytochrome c and Smac/DIABLO into the cytosol. Also, TMS-TMF-4f suppressed both constitutive and IL-6-inducible levels of phosphorylated STAT3 (p-STAT3) and associated proteins such as Mcl-1, cyclin D1, survivin, and c-Myc in both cervical cancer cells. STAT-3 overexpression completely ameliorated TMS-TMF-4f-induced apoptotic cell death and PARP cleavage. Docking analysis revealed that TMS-TMF-4f could bind to unphosphorylated STAT3 and inhibit its interconversion to the activated form. Notably, intraperitoneal administration of TMS-TMF-4f (5, 10, or 20 mg/kg) decreased tumor growth in a xenograft cervical cancer mouse model, demonstrated by the increase in TUNEL staining and PARP cleavage and the reduction in p-STAT3, Mcl-1, cyclin D1, survivin, and c-Myc expression levels in tumor tissues. Taken together, our results suggest that TMS-TMF-4f may potentially inhibit human cervical tumor growth through the induction of apoptosis via STAT3 suppression.
We previously reported that 5-[4-(4-fluorophenoxy) phenyl] methylene-3-{4-[3-(4-methylpiperazin-1-yl)propoxy]phenyl}-2-thioxo-4-thiazolidinone dihydrochloride (KSK05104) has potent, selective and metabolically stable IKKβ inhibitory activities. However, the apoptosis-inducing of KSK05104 and its underlying mechanism have not yet been elucidated in human colon cancer cells. We show that KSK05104 triggered apoptosis, as indicated by externalization of Annexin V-targeted phosphatidylserine residues in HT-29 and HCT-116 cells. KSK05104 induced the activation of caspase-8, -9, and -3, and the cleavage of poly (ADP ribose) polymerase-1 (PARP-1). KSK05104-induced apoptosis was significantly suppressed by pretreatment with z-VAD-fmk (a broad caspase inhibitor). KSK05104 also induced release of cytochrome c (Cyt c), apoptosis inducing factor (AIF), and endonuclease G (Endo G) by damaging mitochondria, resulting in caspase-dependent and -independent apoptotic cell death. KSK05104 triggered endoplasmic reticulum (ER) stress and changed the intracellular calcium level ([Ca2+]i). Interestingly, treatment with KSK05104 activated not only ER stress marker proteins including inositol-requiring enzyme 1-alpha (IRE-1α) and protein kinase RNA-like endoplasmic reticulum kinase (PERK), but also μ-calpain, and caspase-12 in a time-dependent manner. KSK05104-induced apoptosis substantially decreased in the presence of BAPTA/AM (an intracellular calcium chelator). Taken together, these results suggest that mitochondrial dysfunction and ER stress contribute to KSK05104-induced apoptosis in human colon cancer cells.