Evaluation of chemopreventive potentials of ethanolic extract of Ruta graveolens against A375 skin melanoma cells in vitro and induced skin cancer in mice in vivo / 中西医结合学报

<p><b>OBJECTIVE</b>Chemopreventive approach with natural products, particularly plants and plant-derived ones, is receiving increasing attention for their effective role against cancer without any palpable side effects. In this study, efficacy of ethanolic extract of Ruta graveolens (RG) on skin melanoma cells (A375) in vitro and on 7,12-dimethylbenz(a)anthracene (DMBA)-induced skin cancer in vivo has been tested in Swiss albino mice.</p><p><b>METHODS</b>Studies on cell viability, apoptosis and autophagy induction were conducted in vitro. To check apoptosis, assays like alteration in mitochondrial membrane potential, annexin V-fluorescein isothiocyanate/propidium iodide assay and immunoblot were performed. Fluorescence microscopic and immunoblot assays were performed to confirm autophagy induction. The effects of RG were determined by evaluating body weight, tumor incidence, tumor volume and tumor burden in mice. Enzymatic and non-enzymatic antioxidant status was assessed. The role of some relevant signaling proteins was also analyzed.</p><p><b>RESULTS</b>RG caused death of A375 cells through induction of caspase 3-mediated apoptosis and Beclin-1-associated autophagy. Moreover, RG administration (75 mg/kg body weight) which showed no acute or chronic toxicity, showed significant reduction in the skin tumor burden of DMBA-painted mice. RG also demonstrated potent anti-lipid peroxidative and antioxidant functions during the course of skin cancer induction by DMBA.</p><p><b>CONCLUSION</b>Chemopreventive potential of RG was demonstrated from overall results of this study, indicating its possible use in therapeutic formulation of an effective drug to treat skin cancer.</p>

Oleanolic acid isolated from ethanolic extract of Phytolacca decandra induces apoptosis in A375 skin melanoma cells: drug-DNA interaction and signaling cascade / 中西医结合学报

<p><b>OBJECTIVE</b>Oleanolic acid (OA) has been reported to have anticancer effects, but the extent of its cytotoxicity, its ability to interact with nuclear DNA, its action against skin melanoma, as well as the molecular mechanism of its action against cell proliferation and in support of cell death are still unexplored. This led us to examine the efficacy of OA, a bioactive compound isolated from Phytolacca decandra, on these issues in the present investigation.</p><p><b>METHODS</b>Studies related to analyses of cell viability, drug-DNA interaction, cell proliferation, cell cycle and epidermal growth factor receptor (EGFR) activity were performed. To investigate whether cells undergo apoptosis, studies like fluorescence microscopy, poly (ADP-ribose) polymerase (PARP) degradation, annexin V-fluorescein isothiocyanate/propidium iodide assay, alteration in mitochondrial membrane potential and activity of some relevant signaling proteins were performed.</p><p><b>RESULTS</b>OA displayed a minimal and negligible cytotoxic effect on normal HaCaT cells (skin keratinocytes) and peripheral blood mononuclear cells but by contrast it reduced A375 cell viability significantly. OA interacted with nuclear DNA quickly after exposure. It acted as an anti-proliferative agent. It suppressed EGFR activity. OA administration led the cells to mitochondria-dependent caspase 3-mediated apoptosis.</p><p><b>CONCLUSION</b>OA interacts with cellular DNA, inhibits proliferation possibly through modulating EGFR activity and induces mitochondria-dependent caspase 3-mediated apoptosis in A375 cells which would qualify it as a potent anticancer agent.</p>

Low doses of ethanolic extract of Boldo (Peumus boldus) can ameliorate toxicity generated by cisplatin in normal liver cells of mice in vivo and in WRL-68 cells in vitro, but not in cancer cells in vivo or in vitro / 中西医结合学报

<p><b>OBJECTIVE</b>Use of cisplatin, a conventional anticancer drug, is restricted because it generates strong hepatotoxicity by accumulating in liver. Therefore its anticancer potential can only be fully exploited if its own toxicity is considerably reduced. Towards this goal, ethanolic extract of the plant, Boldo (Peumus boldus), known for its antihepatotoxic effects, was used simultaneously with cisplatin, to test its ability to reduce cisplatin's cytotoxicity without affecting its anticancer potential.</p><p><b>METHODS</b>The cytotoxicity of Boldo extract (BE) and cisplatin, administered alone and in combination, was determined in three cancer cell lines (A549, HeLa, and HepG2) and in normal liver cells (WRL-68). Drug-DNA interaction, DNA damage, cell cycle, apoptosis, reactive oxygen species (ROS) and mitochondrial membrane potential (MMP, ΔΨ) were also studied. Hepatotoxicity and antioxidant activity levels were determined by alanine aminotransferase, aspartate aminotransferase, lactate dehydrogenase and glutathione assays in mice. The cytotoxicity of related proteins was tested by Western blotting.</p><p><b>RESULTS</b>Co-administration of BE and cisplatin increased viability of normal cells, but had no effect on the viability of cancer cells. Boldo protected liver from damage and normalized different antioxidant enzyme levels in vivo and also reduced ROS and re-polarized MMP in vitro. Bax and cytochrome c translocation was reduced with caspase 3 down-regulation. Further, a drug-DNA interaction study revealed that BE reduced cisplatin's DNA-binding capacity, resulting in a reduction in DNA damage.</p><p><b>CONCLUSION</b>Results indicated that a low dose of BE could be used beneficially in combination with cisplatin to reduce its toxicity without hampering cisplatin's anticancer effect. These findings signify a potential future use of BE in cancer therapy.</p>

Homeopathic Thuja 30C ameliorates benzo(a)pyrene-induced DNA damage, stress and viability of perfused lung cells of mice in vitro / 中西医结合学报

<p><b>OBJECTIVE</b>To examine if the ultra-highly diluted homeopathic remedy Thuja 30C can ameliorate benzo(a)pyrene (BaP)-induced DNA damage, stress and viability of perfused lung cells of Swiss albino mice in vitro.</p><p><b>METHODS</b>Perfused normal lung cells from mice were cultured in 5% Roswell Park Memorial Institute medium and exposed to BaP, a potent carcinogen, at the half maximal inhibitory concentration dose (2.2 μmol/L) for 24 h. Thereafter, the intoxicated cells were either treated with Thuja 30C (used against tumor or cancer) or its vehicle media, succussed alcohol 30C. Relevant parameters of study involving reactive oxygen species (ROS) accumulation, total glutathione (GSH) content, and generations of heat shock protein (hsp)-90 were measured; the cell viability and other test parameters were measured after treatment with either Thuja 30C or its vehicle media. Circular dichroism spectroscopy was performed to examine if Thuja 30C directly interacted with calf thymus DNA as target. For ascertaining if DNA damaged by BaP could be partially repaired and restituted by the remedy, 4',6-diamidino-2-phenylindole staining was performed.</p><p><b>RESULTS</b>Thuja 30C increased cell viability of BaP-intoxicated cells significantly, as compared to drug-untreated or drug-vehicle control. A minimal dose of Thuja 30C significantly inhibited BaP-induced stress level, by down-regulating ROS and hsp-90, and increasing GSH content. Thuja 30C itself had no DNA-damaging effect, and no direct drug-DNA interaction. However, it showed quite striking ability to repair DNA damage caused by BaP.</p><p><b>CONCLUSION</b>Thuja 30C ameliorates BaP-induced toxicity, stress and DNA damage in perfused lung cells of mice and it apparently has no effect on normal lung cells.</p>

Diarylheptanoid-myricanone isolated from ethanolic extract of Myrica cerifera shows anticancer effects on HeLa and PC3 cell lines: signalling pathway and drug-DNA interaction / 中西医结合学报

<p><b>OBJECTIVE</b>To test if myricanone (C21H24O5), a cyclic diarylheptanoid, has anticancer effects on two different cancer cell lines HeLa and PC3. The present study was conducted with a note on the drug-DNA interaction and apoptotic signalling pathway.</p><p><b>METHODS</b>Several studies like cytotoxicity, nuclear damage, annexin-V-fluorescein isothiocyanate (FITC)/propidium iodide (PI)-labelled apoptotic assay and cell cycle arrest, immunoblot and reverse transcriptase-polymerase chain reaction (RT-PCR) were used following standard protocols. Circular dichroism (CD) spectroscopy was also done to evaluate whether myricanone effectively interacted with DNA to bring about conformational changes that could strongly inhibit the cancer cell proliferation.</p><p><b>RESULTS</b>Myricanone showed a greater cytotoxic effect on PC3 cells than on HeLa cells. Myricanone promoted G0/G1 arrest in HeLa cells and S phase arrest in PC3 cells. Nuclear condensation and annexin V-FITC/PI studies revealed that myricanone promoted apoptotic cell death. CD spectroscopic data indicated that myricanone had an interaction with calf thymus DNA that changed DNA structural conformation. RT-PCR and immunoblot studies revealed that myricanone activated the apoptotic signalling cascades through down-regulation of transcription factors like nuclear factor-κB (NF-κB) (p65), and signal transducers and activators of transcription 3 (STAT3); cell cycle regulators like cyclin D1, and survivin and other signal proteins like Bcl-2 and up-regulation of Bax, caspase-9 and caspase-3.</p><p><b>CONCLUSION</b>Myricanone induced apoptosis in both types of cancer cells by triggering caspase activation, and suppression of cell proliferation by down-regulation of NF-κB and STAT3 signalling cascades, which makes it a suitable candidate for possible use in the formulation of therapeutic agent for combating cancer.</p>