Calcium sulfide (CaS) nanostructures have the potential to play an important role as cadmium‐free nanoscaled semiconductors with applications in bioimaging, in vivo labeling, and sensing, and for drug delivery systems. The objective of this work is to establish the effect of CaS nanostructures on cell replication rate and survival of human mammary adenocarcinoma cell lines. Human adenocarcinoma cell lines are grown in eagle’s minimum essential medium (EMEM). Single doses of dispersions containing traces of CaS nanostructures were added to human mammary adenocarcinoma cell lines with a 70 % confluence. After a 24 hour period, 200,000 cancer cells were subculture in T‐75 treated flasks. The number of dead cells in the cell culture media supernatant was determined in intervals of 24 hours using a Biorad T10 cell counter. The number of dead cells in the supernatant is found to increase from 2,000 in control cell cultures to over 70,000 in cancer cell cultures exposed to a single dose of the CaS dispersion in the first 24 hours: this represents 35 % of the initial cell seeding. The number of dead cells remains in the range of 60,000 to 30,000 in measurements performed between 48 and 72 hours following the single dose of the dispersion containing the CaS nanostructures. The number of replicating cells is found to decrease in the first 72 hours and to increase thereafter. We conclude that the CaS nanostructures affect the replication rate and survival of human adenocarcinoma cells and demonstrate the role CaS nanostructures may play to treat localized cancers. Grant Funding Source: NIH NIGMS‐R25GM088023 and NIGMS‐R25GM096955

PPARgamma (PPARG) is a transcription factor that associates with retinoic acid receptor to enhance transcription of genes regulating pathways of adipogenesis, macrophage programming, growth, and inflammation. PPARg agonists are effective at preventing lung cancer in mice and cause regression of human pre‐neoplastic lung lesions. However, the mechanisms by which PPARg prevents lung cancer progression are not completely understood. Herein, we examined the effects of endogenous and exogenous PPAR agonists on expression of PPARg‐regulated genes (E‐cadherin and Ptgs2) in human lung cancer A549 cells. We treated cells with the endogenous PPARg agonist 15‐PGJ2and exogenous agonists pioglitazone (Pio) and iloprost. We also tested acrolein (component of cigarette smoke) and 4‐hydroxynonenol (4‐HNE; increased in the lungs of smokers). These molecules are chemically related to 15‐Deoxy‐Δ12,14‐prostaglandin J2 (15‐PGJ2), and 4‐HNE has been shown to enhance PPARg activity. We found that Pio, iloprost, and 15‐PGJ2increased expression of E‐cadherin at 24h and 48h of exposure. HPGD expression was increased at 24 h with Pio, iloprost, 15‐Deoxy‐Δ12,14‐prostaglandin J2, and 4‐HNE, but returned to baseline by 48 h. NFκB protein is down‐regulated in the presence of PPARg, but its gene expression increased with Pio, iloprost, 15‐Deoxy‐Δ12,14‐prostaglandin J2, and acrolein exposure at 24 h, indicating that decreased protein leads to increased transcription. The peak of agonist‐induced expression effects occurs by 24 h. Increases in expression of the Pio off‐target regulated gene HPGD with agonists other than Pio indicates that regulation of these genes is more complicated than was previously thought.

Preliminary results in our lab showed that naked Calcium Sulfide (CaS) nanoparticles (5.0nm) decreased cell proliferation in the carcinoma cell lines CRL‐2124. Objective: The objective of this study was to determine if CaS clusters measuring < 3.0 nm were cytotoxic to malignant cells when compared to benign fibroblasts CRL‐2522 by using the n3D BiOAssay (Biosciences, Inc.). Methods: A total of 100,000 cells per cell line were seeded in T‐75 flasks. When reaching 80% confluence, they were incubated with the n3D nano‐shuttles overnight (ON) at 37oC, 5% CO2, and 98% relative humidity. Next day, cells were trypsinized, counted, and seeded (1.4 ‐ 1.6 M/per well) in 6‐well plates using the n3D BiOAssay to levitate the cells. A total of 150,000 cells/well were seeded in a 96‐well plate in triplicates with a total volume of 300ul (150ul of cells, 120ul of media, and 30ul of the treatments). The treatments consist of 10 pmoles of CaS, 2% DMSO, or growth media. Analysis for cytotoxicity were performed with the ImageJ software by measuring the “O” ring outer and inner diameters. Results: The cell were successfully levitated by the n3D BiOAssay System. The expected “O” ring was formed before the treatments were added. We observed changes in the diameters for the CaS treated wells. Conclusions: The n3D BiOAssay provides an excellent and cost effective system for testing cellular toxicity of compounds with the potential to be used as therapeutic agents. We found that malignant cells treated with CaS showed more cytotoxicity than benign normal cells. CaS clusters may represent a novel Cancer Cell Targeted Therapy. Grant Funding Source: NIH‐NIGMSR25GM096955, NIH‐R25GM088023