Celecoxib and LLW-3-6 Reduce Survival of Human Glioma Cells Independently and Synergistically with Sulfasalazine.

Gliomas are among the most commonly diagnosed central nervous system tumors. Celecoxib has been utilized with success in the treatment of several types of cancer, including gliomas. The present study examined the antiproliferative effects of celecoxib and its benzimidazole-based analog, LLW-3-6, when used as co-treatment with sulfasalazine against human glioma LN18 cells. At 48-h treatment, the glioma cells maintained 60% viability in the presence of celecoxib or LLW-3-6 at the maximum concentration tested (40 µM). Co-treatment of glioma cells under a non-lethal dose (50 µM) of sulfasalazine and either celecoxib or LLW-3-6 (administered at different concentrations) resulted in improved inhibition of cell viability. The concentration of the molecules required to reduce cell growth in the combined treatment was significantly less than that needed when either molecule was administered independently. Based on computational values, LLW-3-6 has physiochemical characteristics that should allow for improved bioavailability in comparison to that of celecoxib.

LLW-3-6 and celecoxib impacts growth in prostate cancer cells and subcellular localization of COX-2.

The proliferation in human prostate carcinomas, PC3 and MDA-PCa-2b, was analyzed for cells treated with LLW-3-6 and celecoxib in the presence and absence of sulfasalazine. LLW-3-6 was more potent than celecoxib at mediating a dose-dependent reduction of viable PC3 cells. Co-treatment with a non-lethal dose of sulfasalazine diminished the potency of both drugs in this cell line. The effects of the drugs in MDA-PCa-2b cells were less significant than those observed in the PC3 cells. Localization of COX-2 in LLW-3-6- and CBX-treated PC3 cells is consistent with protein aggregation known for cells responding to stress stimuli. To complement this, an analysis of the theoretical binding interactions of LLW-3-6 was completed to illustrate the potential of LLW-3-6 to bind to COX-2 in a manner similar to that of celecoxib. Studies to further define the mechanism of action for LLW-3-6 are ongoing.

Benzimidazoles diminish ERE transcriptional activity and cell growth in breast cancer cells.

Estrogen receptors (ERα and ERß) are members of the nuclear receptor superfamily. They regulate the transcription of estrogen-responsive genes and mediate numerous estrogen related diseases (i.e., fertility, osteoporosis, cancer, etc.). As such, ERs are potentially useful targets for developing therapies and diagnostic tools for hormonally responsive human breast cancers. In this work, two benzimidazole-based sulfonamides originally designed to reduce proliferation in prostate cancer, have been evaluated for their ability to modulate growth in estrogen dependent and independent cell lines (MCF-7 and MDA-MB 231) using cell viability assays. The molecules reduced growth in MCF-7 cells, but differed in their impact on the growth of MDA-MB 231 cells. Although both molecules reduced estrogen response element (ERE) transcriptional activity in a dose dependent manner, the contrasting activity in the MDA-MB-231 cells seems to suggest that the molecules may act through alternate ER-mediated pathways. Further, the methyl analog showed modest selectivity for the ERß receptor in an ER gene expression array panel, while the naphthyl analog did not significantly alter gene expression. The molecules were docked in the ligand binding domains of the ERα-antagonist and ERß-agonist crystal structures to evaluate the potential of the molecules to interact with the receptors. The computational analysis complimented the results obtained in the assay of transcriptional activity and gene expression suggesting that the molecules upregulate ERß activity while down regulating that of ERα.

Celecoxib and Bcl-2: emerging possibilities for anticancer drug design.

Celecoxib is a multifaceted drug with promising anticancer properties. A number of studies have been conducted that implicate the compound in modulating the expression of Bcl-2 family members and mitochondria-mediated apoptosis. The growing data surrounding the role of celecoxib in the regulation of the mitochondrial death pathway provides a platform for ongoing debate. Studies that describe celecoxib's properties as a BH3 mimic or as a direct inhibitor of Bcl-2 are not available. The motivations for this review are: to provide the basis for the development of novel compounds that modulate Bcl-2 expression using celecoxib as a structural starting point and to encourage additional biological studies (such as binding and enzymatic assays) that would provide information regarding celecoxib's role as a Bcl-2 antagonist. The current review summarizes work that identifies the role of celecoxib in blocking the activity of Bcl-2.

Nucleophilic Aromatic Substitution, A Guided Inquiry Laboratory Experiment.

Inquiry-based learning is a unique student-centered alternative to traditional instruction. This form of active learning is ideal for the organic chemistry laboratory as it encourages critical thinking and hands on problem solving to complete an experiment. Electrophilic Aromatic Substitution is immediately associated with the undergraduate organic chemistry course. However, nucleophilic aromatic substitution is not. The N-arylation of aniline derivatives is a useful reaction for implementing nucleophilic aromatic substitution into the undergraduate curriculum. Under the framework of inquiry-based learning, a straightforward procedure has been developed for the undergraduate laboratory. This experiment explores the reaction rate of the nucleophilic aromatic substitution using various electrophiles. The reaction is conducted under microwave irradiation and the experiment is completed in one laboratory setting.

Structure activity relationship of antiproliferative agents using multiple linear regression.

With cancer-related fatalities being the second leading cause of death in the USA, understanding the activity of effective chemotherapeutic agents is critical to addressing prostate and other cancers. Celecoxib, an FDA-approved drug for the treatment of colon tumors, has been used successfully as a lead compound in the development of antiproliferative agents. The ability of celecoxib to inhibit the development and progression of tumors has been connected to a number of mechanisms of actions that are both dependent on and independent of its cyclooxygenase-2 activity. A structure-based approach has been employed to develop a model that underscores the structural significance of celecoxib as an antiproliferative agent. By evaluating the structure activity of this library of molecules, we were able to create a QSAR model for predicting the antiproliferative activity of structurally similar molecules. The development of the model will be presented in this paper.

A Preliminary Assessment of the Structure-Activity Relationship of Benzimidazole-Based Anti-Proliferative Agents.

PDK1 is pivotal in the development and progression of several cancers. A 3D pharmacophore was developed for pyrazole derivatives displaying anti-proliferative activity and PDK1 inhibition. The pharmacophore was utilized in the design of benzimidazole analogs. Our preliminary results indicate the pharmacophore should be useful in designing PDK1 inhibitors and anti-proliferative agents.