Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0029463 (osteosarcoma)
 16,637 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The influence of poly(ADP-ribose) synthesis inhibitors on mammalian cell radiosensitivity was investigated. Four different inhibitors were studied: 3-methoxybenzamide, 3-aminobenzamide, 6-aminonicotinamide and nicotinamide. When exponentially growing or plateau phase cells are incubated before irradiation with non-toxic concentrations of these compounds, their radiosensitivity is enhanced except in the case of nicotinamide. The poly(ADP-ribose) inhibitors do not modify the repair of sublethal damage, but totally suppress the repair of potentially lethal damage, as shown by the survival of CHO cells and of a human osteosarcoma cell line.
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PMID:Influence of poly(ADP-ribose) synthesis inhibitors on the repair of sublethal and potentially lethal damage in gamma-irradiated mammalian cells. 315 22

Direct monitoring of cell death (i.e., apoptosis and necrosis) during or shortly after treatment is desirable in all cancer therapies to determine the outcome. Further differentiation of apoptosis from necrosis is crucial to optimize apoptosis-favored treatment protocols. We investigated the potential modality of using tissue intrinsic fluorescence chromophore, reduced nicotinamide adenine dinucleotide (NADH), for cell death detection. We imaged the fluorescence lifetime changes of NADH before and after staurosporine (STS)-induced mitochondria-mediated apoptosis and hydrogen peroxide (H2O2)-induced necrosis, respectively, using two-photon fluorescence lifetime imaging in live HeLa cells and 143B osteosarcoma. Time-lapsed lifetime images were acquired at the same site of cells. In untreated cells, the average lifetime of NADH fluorescence was approximately 1.3 ns. The NADH average fluorescence lifetime increased to approximately 3.5 ns within 15 min after 1 microM STS treatment and gradually decreased thereafter. The NADH fluorescence intensity increased within 15 min. In contrast, no significant dynamic lifetime change was found in cells treated with 1 mM H2O2. Our findings suggest that monitoring the NADH fluorescence lifetime may be a valuable noninvasive tool to detect apoptosis and distinguish apoptosis from necrosis for the optimization of apoptosis-favored treatment protocols and other clinical applications.
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PMID:Differentiation of apoptosis from necrosis by dynamic changes of reduced nicotinamide adenine dinucleotide fluorescence lifetime in live cells. 1902 91

Melatonin, the main secretory product of the pineal gland, has potent antitumor activity against various types of cancer. However, the molecular mechanisms underlying the effects of melatonin remain largely unknown. SIRT1, a conserved nicotinamide adenine dinucleotide (NAD(+))-dependent deacetylase, has been implicated in modulating transcriptional silencing and cell survival and plays a key role in carcinogenesis through the deacetylation of important regulatory proteins. In this study, we assessed the antitumor activity of melatonin against human osteosarcoma cells (9607 cell line) and explored the role of SIRT1 in the activity of melatonin. Melatonin treatment resulted in strong antitumor activity, as evidenced not only by reductions in tumor cell vitality, adhesion ability, migration ability and glutathione (GSH) levels but also by increase in the apoptotic index and reactive oxygen species. Additionally, melatonin treatment down-regulated SIRT1 and up-regulated acetylated-p53. Sirtinol (a known SIRT1 inhibitor) and SIRT1 siRNA further enhanced the antitumor activity of melatonin, while SRT1720 (a known SIRT1 activator) attenuated the antitumor activity of melatonin. In summary, melatonin is a potent inhibitor of osteosarcoma cell growth that targets SIRT1 signaling, and the inhibition of SIRT1 signaling is a novel mechanism of action for melatonin during therapeutic intervention in osteosarcoma.
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PMID:SIRT1 inhibition by melatonin exerts antitumor activity in human osteosarcoma cells. 2372 49