Cell specific apoptosis by RLX is mediated by NFκB in human colon carcinoma HCT-116 cells

BACKGROUND: Resistance to chemotherapy represents a major obstacle in correcting colorectal carcinomas (CRC). Inspite of recent advances in the treatment of metastatic disease, the prognosis of the patients remains poor. RLX, a vasicinone analogue has been reported to possess potent bronchodilator, anti-asthmatic and anti-inflammatory properties. However, its anti-cancer activity is unknown. RESULTS: Here, we report for the first time that RLX has anti-cancer property against panel of human cancer cell lines and most potent activity was found against HCT-116 cells with IC(50) value of 12 μM and have further investigated the involvement of NFκB and caspase-3 in RLX action in CRC apoptosis. Following RLX and BEZ-235 treatment in HCT-116, we observed significant down-regulation of NFκB (1 to 0.1 fold) and up-regulation of caspase-3 (1 to 2 fold) protein expressions. Additionally, morphological studies revealed membrane blebbing, cell shrinkage, chromatin condensation and finally apoptosis in HCT-116 cells. CONCLUSIONS: Overall, these findings indicate that RLX is a potent small molecule which triggers apoptosis, and promising potential candidate to be a chemotherapeutic agent

6-Nitro-2-(3-hydroxypropyl)-1H-benz[de]isoquinoline-1,3-dione, a potent antitumor agent, induces cell cycle arrest and apoptosis

<p>Abstract</p> <p>Background</p> <p>Anticancer activities of several substituted naphthalimides (1H-benz[de]isoquinoline-1,3-diones) are well documented. Some of them have undergone Phase I-II clinical trials. Presently a series of ten N-(hydroxyalkyl) naphthalimides (compounds <b>1a-j) </b>were evaluated as antitumor agents.</p> <p>Methods</p> <p>Compounds <b>1a-j </b>were initially screened in MOLT-4, HL-60 and U-937 human tumor cell lines and results were compared with established clinical drugs. Cytotoxicities of compounds <b>1d </b>and <b>1i </b>were further evaluated in a battery of human tumor cell lines and in normal human peripheral blood mononuclear cells. Cell cycle analysis of compound <b>1i </b>treated MOLT-4 cells was studied by flow cytometry. Its apoptosis inducing effect was carried out in MOLT-4 and HL-60 cells by flow cytometry using annexin V-FITC/PI double staining method. The activities of caspase-3 and caspase-6 in MOLT-4 cells following incubation with compound <b>1i </b>were measured at different time intervals. Morphology of the MOLT-4 cells after treatment with <b>1i </b>was examined under light microscope and transmission electron microscope. ³H-Thymidine and ³H-uridine incorporation in S-180 cells in vitro following treatment with 8 μM concentration of compounds <b>1d </b>and <b>1i </b>were studied.</p> <p>Results</p> <p>6-Nitro-2-(3-hydroxypropyl)-1H-benz[de]isoquinoline-1,3-dione (compound <b>1i</b>), has exhibited maximum activity as it induced significant cytotoxicity in 8 out of 13 cell lines employed. Interestingly it did not show any cytotoxicity against human PBMC (IC₅₀value 273 μM). Cell cycle analysis of compound <b>1i </b>treated MOLT-4 cells demonstrated rise in sub-G₁fraction and concomitant accumulation of cells in S and G₂/M phases, indicating up-regulation of apoptosis along with mitotic arrest and/or delay in exit of daughter cells from mitotic cycle respectively. Its apoptosis inducing effect was confirmed in flow cytometric study in MOLT-4 and the action was mediated by activation of both caspase 3 and 6. Light and transmission electron microscopic studies corroborated its apoptosis inducing efficacy at a concentration of 10 μM in MOLT-4 cells. Its apoptosis induction was also observed in HL-60 cells to an extent much greater than well known apoptosis inducing agents as camptothecin and cis-platin at 10 μM concentration each. It significantly inhibited DNA and RNA synthesis in S-180.</p> <p>Conclusions</p> <p>In essence, compound <b>1i </b>showed potential as an antitumor agent.</p

Anticancer activity of an essential oil from Cymbopogon flexuosus

The essential oil froma lemon grass variety of Cymbopogon flexuosuswas studied for its in vitro cytotoxicity against twelve human cancer cell lines. The in vivo anticancer activity of the oil was also studied using both solid and ascitic Ehrlich and Sarcoma-180 tumor models in mice. In addition, the morphological changes in tumor cells were studied to ascertain the mechanism of cell death. The in vitro cytotoxicity studies showed dose-dependent effects against various human cancer cell lines. The IC50 values of oil ranged from 4.2 to 79�g/ml depending upon the cell line. In 502713 (colon) and IMR-32 (neuroblastoma) cell lines, the oil showed highest cytotoxicity with IC50 value of 4.2 and 4.7�g/ml, respectively. Intraperitoneal administration of the oil significantly inhibited both ascitic and solid forms of Ehrlich and Sarcoma-180 tumors in a dose-dependent manner. The tumor growth inhibition at 200 mg/kg (i.p.) of the oil observed with both ascitic and solid tumor forms of Ehrlich Ascites carcinoma was 97.34 and 57.83 respectively. In case of Sarcoma-180, the growth inhibition at similar dose of oil was 94.07 and 36.97% in ascitic and solid forms respectively. Morphological studies of the oil treated HL-60 cells revealed loss of surface projections, chromatin condensation and apoptosis. The mitochondria showed apparent loss of cristae in the cells undergoing apoptosis. The morphological studies of Sarcoma-180 solid tumor cells from animals treated with the oil revealed condensation and fragmentation of nuclei typical of apoptosis. Morphological studies of ascites cells from animals treated with the oil too revealed the changes typical of apoptosis. Our results indicate that the oil has a promising anticancer activity and causes loss in tumor cell viability by activating the apoptotic process as identified by electron microscopy

Potentiation of the antitumor effect of 11-keto-β-boswellic acid by its 3-α-hexanoyloxy derivative

We recently discovered that a propionyloxy derivative of 11-keto-β-boswellic acid (PKBA) showed better anticancer potential than other boswellic acids including AKBA, encompassing the importance of acyl group at the 3-α-hydroxy position of KBA. In continuation of our previous work, other higher derivatives (with increasing alkoxy chain length at 3-α-hydroxy position) including butyryloxy (BKBA) and hexanoyloxy(HKBA) derivatives of KBA were synthesized. The respective IC50 values of BKBA and HKBA in HL-60 cells were found to be 7.7 and 4.5 μg/ml. IC50 value of HKBA was comparatively lower than that of BKBA, and further lower than that of the previously reported derivative (PKBA, IC50 8.7 μg/ml). In order to compare the anticancer potential of HKBA with PKBA, detailed in vitro pro-apoptotic and in vivo anticancer studies were carried out. The induction of apoptosis by HKBA was measured using various parameters including fluorescence and scanning electron microscopy, DNA fragmentation and Annexin V-FITC binding. The extent of DNA damage was measured using neutral comet assay. HKBA was further evaluated for its effect on DNA cell cycle and mitochondria where it was found to arrest cells in G2/M phase and also induced loss of mitochondrial membrane potential. These events were associated with increased expression of cytosolic cytochrome c and cleavage of PARP. Target based studies showed that HKBA inhibited the enzymatic activity of topoisomerases I and II at low doses than that of PKBA. In vivo studies also revealed a low dose inhibitory effect of HKBA on ascitic and solid murine tumor models

In Vitro and In Vivo Anticancer Activity of Root Extracts of Sansevieria liberica Gerome and Labroy (Agavaceae)

Introduction. Sansevieria liberica Gerome and Labroy (Agavaceae) is a perennial plant widely distributed in tropical Africa. Preparations of the plant are commonly used across Nigeria for the treatment of inflammatory conditions. Based on the fact that herbal medicine is a strong component of integrative medicine, this study was conducted to evaluate the anticancer activity of root extracts of Sansevieria liberica. Methods. Sulforhodamine B (SRB) in vitro cytotoxicity assay, Sarcoma-180 (S-180) ascites and solid tumor, and L1210 lymphoid leukemia in vivo models were used in this study. Results. SL-A002 (IC50 23 µg/mL with HeLa), SL-A003 (IC50 22 µg/mL with HCT-116), and SL-A004 (IC50 23 and 18 µg/mL with A549 and THP-1, resp.) demonstrated significant activity in the SRB cytotoxicity assay. Potency was highest with the following pairs of extract : cancer cell line: SL-A002 : HeLa (IC50 23 µg/mL), SL-A003 : HCT-116 (IC50 22 µg/mL), and SL-A004 : THP-1 (IC50 18 µg/mL). SL-A002 demonstrated significant dose-dependent antitumor activity in the Sarcoma-180 (S-180) ascites model with peak effect produced at the dose of 120 mg/kg (i.p.) with inhibition of 89.36% compared to 97.96% for 5-FU (20 mg/kg i.p.). The inhibition of tumor growth by SL-A002 in the S-180 solid tumor model was 47.40% compared to a value of 50.18% for 5-FU. SL-A002 was also significantly active in the L1210 lymphoid leukemia model with 158.33% increase in mean survival time, the same value for 5-FU. Conclusions. The hydroethanolic extract of Sansevieria liberica, SL-A002, possesses significant anticancer activity to warrant further extensive study to identify, isolate, and characterize the specific bioactive molecules responsible for the observed antitumor activity and the precise mechanism(s) of action

A cyano analogue of boswellic acid induces crosstalk between p53/PUMA/Bax and telomerase that stages the human papillomavirus type 18 positive HeLa cells to apoptotic death

The p53 tumor suppressor pathway is disrupted by human papillomavirus (HPV) in over 90% of cervical cancers. HPV E6 protein promotes the degradation of p53 thereby inhibiting its stabilization and activation. This study demonstrates that treatment with a novel cyano derivative of 11-keto-;2-boswellic acid, i.e. butyl 2- cyano-3, 11-dioxours-1,12-dien-24-oate (BCDD) reduced the viral E6 mRNA expression and lead to the accumulation of transcriptionally active p53 in the nucleus of HPV18 HeLa cells following DNA damage.Western blot analysis showed that BCDD robustly up regulated time-dependent expression of p53/PUMA/p21 whereas it deprived cells essentially of p-AKT and NF-;AB cell survival signalling cascade. BCDD appeared to gear up PUMA activation through p53 pathway and that both p53 and p21 translocated heavily into the nucleus. Simultaneously, it inhibited anti-apoptotic Bcl-2, augumented Drp-1 expression, disrupted mitochondrial functions causing the activation of proapoptotic proteins and caspases activation. Additionally,BCDD inhibited telomerase expression that's likely to result in a marked reduction of the tumorigenic potential of high-grade cervical cancers. Consequently BCDD caused apoptotic death in cervical cancer cells as evidenced by DNA fragmentation and PARP-cleavage. Further, BCDD did not affect the extrinsic signalling transduction pathway as depicted by its null effect on caspase-8. The in vivo anticancer activity of BCDD was investigated in Ehrlich Ascites carcinoma model where it exhibited tumor regression by 48% at 30 mg/kg, i.p.,in mice. These findings indicated that BCDD is a potential candidate that may be found useful in the management of cervical cancer