To evaluate the ameliorative efficacy of dihydroxy-isosteviol methyl ester (DIME) of Pulsatilla nigricans extract in arsenic-induced DNA damage in testis cells of mice.

To explore if some ultra-highly diluted homeopathic remedies claimed to have antiviral effects can demonstrate any discernible action in the bacteria Escherichia coli through modulating infectivity potentials of the bacteriophage φX174 DNA.

To examine to what degree an ultra-highly diluted homeopathic remedy, Arnica Montana 30C (AM-30C), used in the treatment of shock and injury, can modulate the expression of nucleotide excision repair genes in Escherichia coli exposed to ultraviolet (UV) irradiation.

To determine the ameliorative potentials of Syzygium jambolanum (SJ) extract in L6 skeletal muscle cells in regard to arsenic-induced impairment of optimum glucose homeostasis and improper functioning of mitochondria.

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.

To examine if a homeopathic mother tincture (Phytolacca Decandra) is capable of precipitating silver nanoparticles from silver nitrate (AgNO(3)) and to characterize the biosynthesized nanoparticles for evaluating their biological activities.

OBJECTIVETo 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.

METHODSSeveral 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.

RESULTSMyricanone 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.

CONCLUSIONMyricanone 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.

Antineoplastic Agents, Phytogenic ; pharmacology ; Apoptosis ; drug effects ; Cell Cycle ; drug effects ; Cell Line, Tumor ; Cell Survival ; drug effects ; Circular Dichroism ; DNA ; metabolism ; Diarylheptanoids ; metabolism ; pharmacology ; Female ; Humans ; Male ; Myrica ; chemistry ; Plant Extracts ; analysis ; Signal Transduction ; Spectroscopy, Fourier Transform Infrared