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Rohitukine, a chromone alkaloid extracted from Dysoxylum binectariferum, has a propitious anticancer activity. Our previous study shows that a new Rohitukine derivative IIIM-290 restricts the growth of pancreatic cancer in vivo and in vitro. In the present findings, we report the mechanism of cell death induced by IIIM-290 in MOLT-4 cells (acute lymphoblastic leukemia) and its anticancer potential against various murine leukemic tumor models in vivo. We found that IIIM-290 induced apoptosis through upregulation of different apoptotic proteins like PUMA, BAX, cytochrome c, cleaved (active) caspase-3, and cleaved PARP in MOLT-4 cells. Moreover, IIIM-290 abated mitochondrial membrane potential, elevated calcium levels, reactive oxygen species, and arrested growth of MOLT-4 cells in the synthesis (S) phase of the cell cycle. Interestingly, the elevation in proapoptotic markers was p53 dependent-the silencing of p53 abrogated apoptosis (programmed cell death) triggered by IIIM-290 in MOLT-4 cells. Furthermore, IIIM-290 significantly enhanced the survival of animals with P388 and L1210 leukemia. Thus, our results put IIIM-290 as a potential candidate for the anticancer lead.

A series of rationally designed platanic acid-based compounds derived from naturally occurring betulinic acid were synthesized through a sequence of Lemieux-Johnson oxidation and Aldol condensation reaction. All the compounds were screened for cytotoxicity against a panel of human cancer and normal cell lines using MTT assay. From the biological data, it was observed that some of these semi-synthetic congeners exhibited potent biological profiles compared to platanic acid. One of the compounds with the p-tolyl substitution was found to be most active in this study, and its cytotoxicity against two of the cell lines, MDA-MB 231 and A-549 were in tune with the standard compound, 5-fluorouracil.

A new series of bakuchiol 1 Mannich derivatives was synthesized by reaction with various substituted secondary amines. The analogs were evaluated for cytotoxicity against a panel of three different human cancer cell lines breast (MCF-7), colon (HCT-116) and lung (A549). Cytotoxicity screening results showed that many compounds displayed significant in vitro cytotoxic effects against different cancer cell lines. Compounds 9, 12, 14, 16, 17 and 21 showed promising cytotoxic effects compared to parent molecule 1 and among them compound 14 was found to be most potent analog with IC50 5 μM against all the cell lines examined. It was about 8-fold more potent against MCF-7 and A549 and 10-fold more potent against HCT-116 cell line in comparison to the parent molecule 1. Structure activity relationship (SAR) study of all synthesized derivatives was carried out. Further, compound 14 induced apoptosis in lung cancer cells (A549) through caspase activation followed by PARP-1 cleavage.

In this study, we for the first time explored the cellular and molecular mechanism of anticancer properties of fascaplysin, a marine sponge-derived alkaloid. Our study demonstrated that fascaplysin induced a cooperative interaction between apoptotic and autophagic pathways to induce cytotoxicity in HL-60 cells. Fascaplysin treatment not only activated pro-apoptotic events like PARP-1 cleavage and caspase activation but also triggered autophagy signaling as shown by the increased expression of LC3-II, ATG7and beclin. Interestingly, it was found that use of pan-caspase inhibitor completely reversed the fascaplysin mediated cell death as analyzed by MTT and cell cycle assays. It was observed that cell death as well as the expression of pro-death proteins was partially reversed, when key autophagy mediators ATG7 was silenced by siRNA in fascaplysin treated cells. Cooperative involvement of autophagy and apoptotic signaling in cytotoxicity was confirmed when combined silencing of pro-apototic (PARP-1) and autophagic (ATG-7) signaling by respective siRNA's lead to substantial rescue of cell death induced by fascaplysin. Although, apoptosis and autophagy are two independent cell death pathways, our findings provide detailed insight by which both the pathways acted cooperatively to elicit fascaplysin induced cell death in HL-60 cells. Our findings provide molecular insight into the anti-cancer potential of fascaplysin by showing that both autophagic and apoptotic signaling can work together in the induction of cell death. J. Cell. Biochem. 116: 985–997, 2015. © 2015 Wiley Periodicals, Inc.

Pyrano[2,3-c]carbazoles which are biologically valuable and synthetically challenging frameworks are synthesized in high yields over five steps from commercially available resorcinol. Palladium-catalyzed arylation remains a key step in this novel strategy. The versatility of this protocol has been demonstrated by the synthesis of naturally occurring alkaloid clauraila C and 7-methoxyglycomaurin. The anti-proliferative activity of these designed compounds (5a, 5f, and 5l) has been evaluated in a cancer cell line (MOLT-4). The molecular docking study revealed that this pyrano[2,3-c]carbazole class of molecules selectively occupies the colchicine binding site of the tubulin-polymer.

Intervention of apoptosis is a promising strategy for discovery of novel anti-cancer therapeutics. In this study, we examined the ability of a novel cyano derivative of 11-keto-β-boswellic acid, that is, butyl 2-cyano-3,11-dioxours-1,12-dien-24-oate (BCDD) to induce apoptosis in cancer cells. BCDD inhibited cell proliferation with 48 h IC(50) of 0.67 µM in HL-60, 1 µM in Molt4, and 1.5 µM in THP1 cells. The mechanism of cell death was investigated in HL-60 cells where it caused apoptosis by acting against several potential apoptosis suppressive targets. It inhibited phosphatidylinositol-3-kinase (PI3K)/AKT activity, NF-κB, Hsp-90, and survivin which may enhance the sensitivity of cells to apoptosis. Also, BCDD decreased the activity of Bid and Bax in cytosol, caused ΔΨ(mt) loss, releasing pro-apoptotic cytochrome c, SMAC/DIABLO leading to caspase-9-mediated down stream activation of caspase-3, ICAD, and PARP1 cleavage. Translocation of apoptotis-inducing factor (AIF) from mitochondria to the nucleus indicated some caspases-independent apoptosis. Though it upregulated DR-5 and caspase-8, the caspase inhibitor yet had no effect on apoptosis as against 75% inhibition by caspase-9 inhibitor. Attempts were made to examine any acclaimed role of AIF in the activation of caspase-8 using siRNA where it had no effect on caspase-8 activity while the Bax-siRNA inhibited caspase-3 activation suggesting predominance of intrinsic signaling. Our studies thus demonstrated that BCDD exerts multi-focal action in cancer cells while it required 10-fold higher the concentration to produce cytotoxicity in normal human PBMC and gingival cell line, and therefore, may find usefulness in the management of human leukemia.

Cervical carcinoma is a growing menace to women health worldwide. This study reports the apoptotic cell death in human cervical cancer HeLa and SiHa cells by a pentacyclic triterpenediol (TPD) from Boswellia serrata by a mechanism different from reported in HL-60 cells. It caused oxidative stress by early generation of nitric oxide and reactive oxygen species that robustly up regulated time-dependent expression of p53/p21/PUMA while conversely abrogating phosphatidylinositol-3-kinase (PI3K)/Akt pathways in parallel. TPD also decreased the expression of PI3K/pAkt, ERK1/2, NF-kappaB/Akt signaling cascades which coordinately contribute to cancer cell survival through these distinct pathways. The tumor suppressor p53 pathway predominantly activated by TPD further up-regulated PUMA, which concomitantly decreased the Bcl-2 level, caused mitochondrial membrane potential loss with attendant translocation of Bax and drp1 to mitochondria and release of pro-apoptotic factors such as cytochrome c and Smac/Diablo to cytosol leading to caspases-3 and -9 activation. In addition both the phospho-p53 and p21 were found to accumulate heavily in the nuclear fraction with attendant decrease in topoisomarase II and survivin levels. On the contrary, TPD did not affect the extrinsic signaling transduction pathway effectively through apical death receptors. Interestingly, N-acetyl cysteine, ascorbate and s-methylisothiourea (sMIT) rescued cells significantly from TPD induced DNA damage and caspases activation. TPD may thus find usefulness in managing and treating cervical cancer.

Oral administration of BOS 2000 (1-10 mg/kg) elicited a dose related increase in the delayed hypersensitivity reaction (early 24 h and delayed 48 h) in mice. It also stimulated the IgM and IgG titre expressed in the form of plaques (PFC) and complement fixing antibody titre. The concentration of cytokines (IL-4, IFN-gamma and TNF-alpha) in serum with respect to T cell interactions, i.e. (CD4/CD8) and the proliferation of lymphocytes were significantly increased at 10 mg/kg compared with the control. The results in these studies demonstrated the immunostimulatory effect of BOS 2000 in a dose-dependent manner with respect to the macrophage activation possibly expressing the phagocytosis and nitrite production by the enhancement of TNF-alpha and IFN-gamma production as a mode of action.