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Background: Human respiratory syncytial virus (hRSV) is a highly contagious pathogen and is the most common cause of bronchiolitis and pneumonia for infants and children under one year of age. Worldwide, greater than 33 million children under five years of age are affected by hRSV resulting in three million hospitalizations and 200,000 deaths. However, severe lower respiratory tract disease may occur at any age, especially among the elderly or those with compromised cardiac, pulmonary, or immune systems. There is no vaccine commercially available. Existing therapies for the acute infection are ribavirin and the prophylactic humanized monoclonal antibody (Synagis® from MedImmune) that is limited to use in high risk pediatric patients. Thus, the discovery of new inhibitors for hRSV would be clinically beneficial. Results: We have developed and validated a 384-well cell-based, high-throughput assay that measures the cytopathic effect of hRSV (strain Long) in HEp-2 cells using a luminescent-based detection system for signal endpoint (Cell Titer Glo®). The assay is sensitive and robust, with Z factors greater than 0.8, signal to background greater than 35, and signal to noise greater than 24. Utilizing this assay, 313,816 compounds from the Molecular Libraries Small Molecule Repository were screened at 10 μM. We identified 7,583 compounds that showed greater than 22% CPE inhibition in the primary screen. The top 2,500 compounds were selected for confirmation screening and 409 compounds showed at least 50% inhibition of CPE and were considered active. We selected fifty-one compounds, based on potency, selectivity and chemical tractability, for further evaluation in dose response and secondary assays Several compounds had SI50 values greater than 3, while the most active compound displayed an SI50 value of 58.9. Conclusions: A robust automated luminescent-based high throughput screen that measures the inhibition of hRSV-induced cytopathic effect in HEp-2 cells for the rapid identification of potential inhibitors from large compound libraries has been developed, optimized and validated. The active compounds identified in the screen represent different classes of molecules, including aryl sulfonylpyrrolidines which have not been previously identified as having anti-hRSV activity. [ABSTRACT FROM AUTHOR]

The PTEN tumor suppressor gene is one of the most commonly mutated genes in human cancer. Because inactivation of PTEN is a somatic event, PTEN mutations represent an important genetic difference between cancer cells and normal cells and therefore a potential anticancer drug target. However, it remains a substantial challenge to identify compounds that target loss-of-function events such as mutations of tumor suppressors. In an effort to identify small molecules that preferentially kill cells with mutations of PTEN, the authors developed and implemented a high-throughput, paired cell-based screen composed of parental HCT116 cells and their PTEN gene-targeted derivatives. From 138 758 compounds tested, two hits were identified, and one, N′-[(1-benzyl-1H-indol-3-yl)methylene]benzenesulfonohydrazide (CID1340132), was further studied using a variety of cell-based models, including HCT116, MCF10A, and HEC1A cells with targeted deletion of either their PTEN or PIK3CA genes. Preferential killing of PTEN and PIK3CA mutant cells was accompanied by DNA damage, inhibition of DNA synthesis, and apoptosis. Taken together, these data validate a cell-based screening approach for identifying lead compounds that target cells with specific tumor suppressor gene mutations and describe a novel compound with preferential killing activity toward PTEN and PIK3CA mutant cells. (Journal of Biomolecular Screening 2011;16:383-393) [ABSTRACT FROM PUBLISHER]

West Nile virus (WNV) is a positive sense, single-stranded RNA virus that can cause illness in humans when transmitted via mosquito vectors. Unfortunately, no antivirals or vaccines are currently available, and therefore efficient and safe antivirals are urgently needed. We developed a high throughput screen to discover small molecule probes that inhibit virus infection of Vero E6 cells. A primary screen of a 13,001 compound library at a 10 μM final concentration was conducted using the 384-well format. Z′ values ranged from 0.54-0.83 with a median of 0.74. Average S/B was 17 and S/N for each plate ranged from 10.8 to 23.9. Twenty-six compounds showed a dose response in the HT screen and were further evaluated in a time of addition assay and in a titer reduction assay. Seven compounds showed potential as small molecule probes directed at WNV. The hit rate from the primary screen was 0.185% (24 compounds out of 13,001 compounds) and from the secondary screens was 0.053% (7 out of 13,001 compounds) respectively. [ABSTRACT FROM AUTHOR]