Curcumol induces apoptosis in SPC-A-1 human lung adenocarcinoma cells and displays anti-neoplastic effects in tumor bearing mice.

Curcumol is a sesquiterpene originally isolated from curcuma rhizomes, a component of herbal remedies commonly used in oriental medicine. Its beneficial pharmacological activities have attract significant interest recently. In this study, anti-cancer activity of curcumol was examined with both in vitro and in vivo models. It was found that curcumol exhibited time- and concentration-dependent anti-proliferative effects in SPC-A-1 human lung adenocarcinoma cells with cell cycle arrest in the G0/G1 phase while apoptosis-induction was also confirmed with flow cytometry and morphological analyses. Interestingly, curcumol did not display growth inhibition in MRC-5 human embryonic lung fibroblasts, suggesting the anti-proliferative effects of curcumol were specific to cancer cells. Anti-neoplastic effects of curcumol were also confirmed in tumor bearing mice. Curcumol (60 mg/kg daily) significantly reduced tumor size without causing notable toxicity. In conclusion, curcumol appears a favorable anti-cancer candidate for further development.

Expression and function of GSTA1 in lung cancer cells.

Glutathione S-transferase A1 (GSTA1) appears to be primarily involved in detoxification processes, but possible roles in lung cancer remain unclear. The objective of this study was to investigate the expression and function of GSTA1 in lung cancer cells. Real-time PCR and Western blotting were performed to assess expression in cancer cell lines and the normal lung cells, then verify the A549 cells line with stable overexpression. Localization of GSTA1 proteins was assessed by cytoimmunofluorescence. Three double-strand DNA oligoRNAs (SiRNAs) were synthesized prior to being transfected into A549 cells with Lipofectamine 2000, and then the most efficient SiRNA was selected. Expression of the GSTA1 gene in the transfected cells was determined by real-time PCR and Western blotting. The viability of the transfected cells were assessed by MTT. Results showed that the mRNA and protein expression of A549 cancer cells was higher than in MRC-5 normal cells. Cytoimmunofluorescence demonstrated GSTA1 localization in the cell cytoplasm and/or membranes. Transfection into A549 cells demonstrated that down-regulated expression could inhibit cell viability. Our data indicated that GSTA1 expression may be a target molecule in early diagnosis and treatment of lung cancer.

Induction of caspase-3-dependent apoptosis in human leukemia HL-60 cells by δ-elemene.

  Î´-Elemene, an antitumor component, is a chemical compound isolated from Curcuma wenyujin, a Chinese traditional herb. We examined whether δ-elemene could inhibit cell growth and cell cycle progression and induce apoptosis in human leukemia HL-60 cells. The results demonstrated that δ-elemene induces significant apoptosis of HL-60 cells, as shown by MTT assay, annexin V (AnV) binding of externalized phosphatidylserine (PS), and the mitochondrial probe JC-1 using flow cytometry. HL-60 cells treated with δ-elemene showed high percentages in the early apoptotic and late apoptoctic/necrotic stages, as well as caspase-3 activation of HL-60 cells. By monitoring the changes in cell cycle profiles, we confirmed that δ-elemene could interfere with the cell cycle in the G2/M phase and induce apoptosis in HL-60 cells in a time-dependent manner. Caspase-3 plays a direct role in proteolytic cleavage of the cellular proteins responsible for progression to apoptosis. Therefore we examined apoptosis in HL-60 cells after exposure to δ-elemene and measured caspase-3 activities with or without Z-Val-Ala-Asp-fluoromethylketone (z-VAD-fmk, a broad-spectrum caspase inhibitor) pretreatment using flow cytometric analysis. The results showed that δ-elemene could induce caspase-3 activation as detected by the decrease in δ-elemene-induced caspase-3 activities after treatment with z-VAD-fmk. In the present study, δ-elemene activated typical caspase-dependent apoptosis in HL-60 cells, as demonstrated by an inhibitory effect of z-VAD-fmk on this cell death. During δ-elemene-induced apoptosis, cytochrome c and apoptosis-inducing factor were released into the cytosol and BAX was translocated from the cytosol to mitochondria. However, these were not prevented by z-VAD-fmk. In conclusion, our study demonstrated that δ-elemene could induce G2/M cell cycle transition and trigger apoptosis through a caspase-3-dependent pathway.

B-cell lymphoma-2 over-expression protects δ-elemene-induced apoptosis in human lung carcinoma mucoepidermoid cells via a nuclear factor kappa B-related pathway.

δ-Elemene, an antitumor component, is a chemical compound isolated from Curcuma wenyujin, a Chinese traditional herb. We examined whether δ-elemene could affect apoptosis in human lung carcinoma mucoepidermoid NCI-H292 cells, and test whether and how the over-expression of B-cell lymphoma-2 (Bcl-2) and B-cell lymphoma extra large (Bcl-xL) could off-set the effect of δ-elemene on cell growth. The result demonstrated that δ-elemene significantly induced apoptosis of NCI-H292, as shown by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, DNA fragmentation measurement, Annexin V (AnV) binding of externalized phosphatidylserine and the mitochondrial probe JC-1 using flow cytometry. Treatment of NCI-H292 with δ-elemene increased both p38 mitogen-activated protein kinase (MAPK) and inducible nitric oxide synthese (iNOS) levels, suggesting these two molecules maybe relate to the apoptotic effect of δ-elemene. The cells with Bcl-2 or Bcl-xL over-expression showed an elevation of nuclear factor kappa B (NF-kappa B) activity, accompanying a significant reduction of δ-elemene-induced apoptosis. Furthermore, inhibition of NF-kappa B by IkBαSR, which is a powerful inhibitor of NF-kappa B, restored the ability of δ-elemene to induce apoptosis in the cells transfected with Bcl-2. These data strongly indicated that the apoptotic effect of δ-elemene on NCI-H292 was closely associated with the activity of NF-kappa B, which was up-regulated by Bcl-2 and Bcl-xL. In conclusion, δ-elemene induced apoptosis in NCI-H292 cells. The apoptotic effect of δ-elemene could be significantly offset by over-expression of either Bcl-2 or Bcl-xL. Bcl-2 and Bcl-xL were able to increase the activity of NF-kappa B, which was a known anti-apoptotic molecule in human lung cancer cells.

Scutellarin induced Ca(2+ ) release and blocked KCl-induced Ca(2+ ) influx in smooth muscle cells isolated from rat thoracic artery.

This study was designed to investigate the effect of scutellarin (1) on the modulation of intracellular Ca(2+ ) concentration in thoracic smooth muscle cells of rat. Single smooth muscle cells were obtained enzymatically. Fluo-3 AM was used to determine the alteration of intracellular-free Ca(2+ )([Ca(2+ )](i)) and the changes in fluorescence intensity under different agonists were recorded. Compound 1 induced Ca(2+ ) transients in the medium with and/or without Ca(2+ ). In the Ca(2+ )-free medium, after pretreatment of 1, thapsigargin failed to cause the elevation of [Ca(2+ )](i). However, 1 still caused the elevation of [Ca(2+ )](i) after pretreatment of thapsigargin. The infusion of 1 blocked KCl-induced Ca(2+ ) entry and this effect was hardly reversible. The results of present study suggested that 1 increased [Ca(2+ )](i) by blocking sarcoplasmic reticulum Ca(2+ )/ATPase and blocked voltage-dependent Ca(2+ ) channels in smooth muscle cells of the rat thoracic aortic artery.