Computer Aided Identification of Small Molecules Disrupting uPAR/α5β1- Integrin Interaction: A New Paradigm for Metastasis Prevention

Disseminated dormant cancer cells can resume growth and eventually form overt metastases, but the underlying molecular mechanism responsible for this change remains obscure. We previously established that cell surface interaction between urokinase receptor (uPAR) and alpha5beta1-integrin initiates a sequel of events, involving MAPK-ERK activation that culminates in progressive cancer growth. We also identified the site on uPAR that binds alpha5beta1-integrin. Disruption of uPAR/integrin interaction blocks ERK activation and forces cancer cells into dormancy.Using a target structure guided computation docking we identified 68 compounds from a diversity library of 13,000 small molecules that were predicted to interact with a previously identified integrin-binding site on uPAR. Of these 68 chemical hits, ten inhibited ERK activation in a cellular assay and of those, 2 compounds, 2-(Pyridin-2-ylamino)-quinolin-8-ol and, 2,2'-(methylimino)di (8-quinolinol) inhibited ERK activation by disrupting the uPAR/integrins interaction. These two compounds, when applied in vivo, inhibited ERK activity and tumor growth and blocked metastases of a model head and neck carcinoma.We showed that interaction between two large proteins (uPAR and alpha5beta1-integrin) can be disrupted by a small molecule leading to profound downstream effects. Because this interaction occurs in cells with high uPAR expression, a property almost exclusive to cancer cells, we expect a new therapy based on these lead compounds to be cancer cell specific and minimally toxic. This treatment, rather than killing disseminated metastatic cells, should induce a protracted state of dormancy and prevent overt metastases

Microscopic Characterization and Analysis of Ayurvedic Herbal Products Using Light Microscopy

Objective: Today sophisticated modern research tools for assessment of the plant drugs are achievable but microscopic method is still one of the ingenious and procurable methods to start for substantiate the correct recognition of the source material. Powder microscopy helps to find out the impurities and also helps in quality assessment of the drug. To standardize and evaluate the readymade as well as homemade herbal powder and thus provides means for assessing the authenticity and morality of herbal drugs. Materials and Methods: Microscopic detailed examination of herbal plant parts such as G. glabra, P. emblica, P. nigrum, P. longum was established with different reagents such as acetic acid, iodine, sulphuric acid and hydrochloric acid followed by observation of slide under LEICA Software Capture and Display Software and photographs of each slide was captured for evaluation of the drug. Observation and Results: Microscopic assessment of the homemade and readymade herbal parts of G.glabra and P.emblica shows original cellular structures while unidentified cellular structure were observed in readymade powder of P. longum which perhaps the growth of fungal mycelium and leaf part were observed in P. longum, thus Microscopy method permits more detailed examination of a drug and it can be used to identify the organized drugs by their known histological characters. Conclusion: Powder microscopic evaluation of herbal powder is one of the simplest and authenticated methods for the proper identification of the drug. It helps in purity assessment of the readymade herbal powder. Microscopic study and physiochemical standards can be useful to substantiate and authenticate the drug

Coactivator MYST1 Regulates Nuclear Factor-κB and Androgen Receptor Functions During Proliferation of Prostate Cancer Cells

In prostate cancer (PCa), the functional synergy between androgen receptor (AR) and nuclear factor-κ B (NF-κB) escalates the resistance to therapeutic regimens and promotes aggressive tumor growth. Although the underlying mechanisms are less clear, gene regulatory abilities of coactivators can bridge the transcription functions of AR and NF-κB. The present study shows that MYST1 (MOZ, YBF2 and SAS2, and TIP60 protein 1) costimulates AR and NF-κB functions in PCa cells. We demonstrate that activation of NF-κB promotes deacetylation of MYST1 by sirtuin 1. Further, the mutually exclusive interactions of MYST1 with sirtuin 1 vs AR regulate the acetylation of lysine 16 on histone H4. Notably, in AR-lacking PC3 cells and in AR-depleted LNCaP cells, diminution of MYST1 activates the cleavage of poly(ADP-ribose) polymerase and caspase 3 that leads to apoptosis. In contrast, in AR-transformed PC3 cells (PC3-AR), depletion of MYST1 induces cyclin-dependent kinase (CDK) N1A/p21, which results in G(2)M arrest. Concomitantly, the levels of phospho-retinoblastoma, E2F1, CDK4, and CDK6 are reduced. Finally, the expression of tumor protein D52 (TPD52) was unequivocally affected in PC3, PC3-AR, and LNCaP cells. Taken together, the results of this study reveal that the functional interactions of MYST1 with AR and NF-κB are critical for PCa progression