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31.
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Sijia Sun Min Jo Kim Ashraf M. Omar Nguyen Duy Phan Mio Aoike Suresh Awale 《化学与生物多样性》2021,18(9):e2100389
Pancreatic tumors are hypovascular, which leads to a poor nutrient supply to support the aggressively proliferating tumor cells. However, human pancreatic cancer cells have extreme resistance to nutrition starvation, which enables them to survive under severe metabolic stress conditions within the tumor microenvironment, a phenomenon known as “austerity” in cancer biology. Discovering agents which can preferentially inhibit the cancer cells’ ability to tolerate starvation conditions represents a new generation of anticancer agents. In this study, geranyl 2,4-dihydroxy-6-phenethylbenzoate (GDP), isolated from Boesenbergia pandurata rhizomes, exhibited potent preferential cytotoxicity against PANC-1 human pancreatic cancer cells under nutrition starvation conditions. GDP also possessed PANC-1 cell migration and colony formation inhibitory activities under normal nutrient-rich conditions. Mechanistically, GDP inhibited PI3K/Akt/mTOR/autophagy survival signaling pathway, leading to selective PANC-1 cancer cell death under the nutrition starvation condition. Therefore, GDP is a promising anti-austerity agent for drug development against pancreatic cancer. 相似文献
33.
Juluru Bhaskar Srinivas Bandari Gouthami Dasari Suresh Paidakula 《Russian Journal of Bioorganic Chemistry》2021,47(4):954-962
Russian Journal of Bioorganic Chemistry - A series of novel hybrids of indole-pyrimidine moieties were synthesized and evaluated for their in vitro anti-cancer, in vitro anti-bacteria and... 相似文献
34.
Goda Pankaja Kumar Sekhar Thuraka Thriveni Pinnu Venkateswarlu Annavarapu Peddanna Kotha Reddy Peduri Suresh Krishna Mypati Hari Sreelatha Tumma 《Russian Journal of Bioorganic Chemistry》2021,47(6):1293-1300
Russian Journal of Bioorganic Chemistry - A simple, convenient, environmentally benign method has been developed for the synthesis of spiro-5-cyanopyrimidines by multi-component condensation of... 相似文献
35.
Hogyoung Kim Zakaria Y Abd Elmageed Jihang Ju Amarjit S Naura Asim B Abdel-Mageed Shibu Varughese Dennis Paul Suresh Alahari Andrew Catling Jong G Kim A Hamid Boulares 《Molecular medicine (Cambridge, Mass.)》2013,19(1):253-262
Although a relationship between PDZK1 expression and estrogen receptor (ER)-α stimulation has been suggested, the nature of such a connection and the function of PDZK1 in breast cancer remain unknown. Human tissue microarrays (cancer tissue: 262 cores; normal tissue: 87 cores) and breast cancer cell lines were used to conduct the study. We show that PDZK1 protein expression is tightly correlated with human breast malignancy, is negatively correlated with age and had no significant correlation with ER-α expression levels. PDZK1 exhibited an exclusive epithelial expression with mostly cytosolic subcellular localization. Additionally, 17β-estradiol induced PDZK1 expression above its basal level more than 24 h after treatment in MCF-7 cells. PDZK1 expression was indirectly regulated by ER-α stimulation, requiring insulinlike growth factor 1 receptor (IGF-1R) expression and function. The molecular link between PDZK1 and IGF-1R was supported by a significant correlation between protein and mRNA levels (r = 0.591, p < 0.001, and r = 0.537, p < 0.001, respectively) of the two factors in two different cohorts of human breast cancer tissues. Interestingly, PDZK1 knockdown in MCF-7 cells blocked ER-dependent growth and reduced c-Myc expression, whereas ectopic expression of PDZK1 enhanced cell proliferation in the presence or absence of 17β-estradiol potentially through an increase in c-Myc expression, suggesting that PDZK1 has oncogenic activity. PDKZ1 also appeared to interact with the Src/ER-α/epidermal growth factor receptor (EGFR) complex, but not with IGF-1R and enhanced EGFR-stimulated MEK/ERK1/2 signaling. Collectively, our results clarify the relationship between ER-α and PDZK1, propose a direct relationship between PDZK1 and IGF-1R, and identify a novel oncogenic activity for PDZK1 in breast cancer. 相似文献
36.
K. K. Pulicherla P. Suresh Kumar K. Manideep V. P. B. Rekha Mrinmoy Ghosh K. R. S. Sambasiva Rao 《Preparative biochemistry & biotechnology》2013,43(8):766-780
In the present investigation Thalassospira frigidphilosprofundus, a novel species from the deep waters of the Bay of Bengal, was explored for the production of cold-active β-galactosidase by submerged fermentation using marine broth medium as the basal medium. Effects of various medium constituents, namely, carbon, nitrogen source, pH, and temperature, were investigated using a conventional one-factor-at-a-time method. It was found that lactose, yeast extract, and bactopeptones are the most influential components for β-galactosidase production. Under optimal conditions, the production of β-galactosidase was found to be 3,864 U/mL at 20 ± 2°C, pH 6.5 ± 0.2, after 48 hr of incubation. β-Galactosidase production was further optimized by the Taguchi orthogonal array design of experiments and the central composite rotatable design (CCRD) of response surface methodology. Under optimal experimental conditions the cold-active β-galactosidase enzyme production from Thalassospira frigidphilosprofundus was enhanced from 3,864 U/mL to 10,657 U/mL, which is almost three times higher than the cold-active β-galactosidase production from the well-reported psychrophile Pseudoalteromonas haloplanktis. 相似文献
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P. Suresh Jayasekara Khai Phan Dilip K. Tosh T. Santhosh Kumar Steven M. Moss Guofeng Zhang Joseph J. Barchi Jr. Zhan-Guo Gao Kenneth A. Jacobson 《Purinergic signalling》2013,9(2):183-198
Gold nanoparticles (AuNPs) allow the tuning of pharmacokinetic and pharmacodynamic properties by active or passive targeting of drugs for cancer and other diseases. We have functionalized gold nanoparticles by tethering specific ligands, agonists and antagonists, of adenosine receptors (ARs) to the gold surface as models for cell surface interactions with G protein-coupled receptors (GPCRs). The AuNP conjugates with chain-extended AR ligands alone (PEGylated nucleosides and nonnucleosides, anchored to the Au via thioctic acid) were found to be insoluble in water due to hydrophobic entities in the ligand. Therefore, we added a second, biologically inactive pendant moiety to increase the water solubility, consisting of a PEGylated chain terminating in a carboxylic or phosphate group. The purity and stability of the immobilized biologically active ligand were examined by ultrafiltration and HPLC. Pharmacological receptor binding studies on these GPCR ligand-derivatized AuNPs (2–5 nm in diameter), performed using membranes of mammalian cells stably expressing human A1, A2A, and A3ARs, showed that the desired selectivity was retained with K i values (nanomolar) of A3AR agonist 21b and A2AAR antagonists 24 and 26a of 14 (A3), 34 (A2A), and 69 (A2A), respectively. The corresponding monomers displayed K i values of 37, 61, and 1,420 nM, respectively. In conclusion, we have synthesized stable, water-soluble AuNP derivatives of tethered A3 and A2AAR ligands that retain the biological properties of their monomeric ligands and are intended for therapeutic and imaging applications. This is the first prototypical application to gold carriers of small molecule (nonpeptide) GPCR ligands, which are under investigation for treatment of cancer and inflammatory diseases. 相似文献
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Natarajan Nandhakumar Sundararajan Sathish Suresh C. P. Ramalingam Sathishkumar 《Plant Cell, Tissue and Organ Culture》2020,143(2):485-485
Plant Cell, Tissue and Organ Culture (PCTOC) - This article has been retracted. Please see the retraction notice for more detail: https://doi.org/10.1007/s11240-020-01912-4 相似文献