tolfenamic-acid and Adenocarcinoma

Specificity protein (Sp) transcription factors are implicated in critical cellular and molecular processes associated with cancer that impact tumor growth and metastasis. The non-steroidal anti-inflammatory drug, tolfenamic acid (TA) is known to inhibit Sp proteins in some human cancer cells and laboratory animal models. We evaluated the anti-cancer activity of TA using in vitro and in vivo models for prostate cancer.. The anti-proliferative efficacy of TA was evaluated using DU-145, PC-3, and LNCaP cells. PC-3 cells were treated with DMSO or 50 µM TA for 48 hr. Whole cell lysates were evaluated for the expression of Sp1, survivin, c-PARP, Akt/p-Akt, c-Met, cdk4, cdc2, cyclin D3, and E2F1 by Western blot analysis. Cell invasion was assessed by Boyden-chamber assay and flow cytometry analysis was used to study apoptosis and cell cycle distribution. An orthotopic mouse model for prostate cancer with PC-3-Luc cells was used to study the in vivo effect of TA.. TA inhibited the expression of Sp1, c-Met, p-Akt, and survivin; increased c-PARP expression and caspases activity in PC-3 cells. TA caused cell arrest at G(0) /G(1) phase accompanied by a decrease in cdk4, cdc2, cyclin D3, and E2F1 and an increase in critical apoptotic markers. TA augmented annexin-V staining, caspase activity, and c-PARP expression indicating the activation of apoptotic pathways. TA also decreased PC-3 cell invasion. TA significantly decreased the tumor weight and volume which was associated with low expression of Sp1 and survivin in tumor sections.. TA targets critical pathways associated with tumorigenesis and invasion. These pre-clinical data strongly demonstrated the anti-cancer activity of TA in prostate cancer.

Topics: Adenocarcinoma; Animals; Anti-Inflammatory Agents, Non-Steroidal; Antineoplastic Agents; Apoptosis; Biomarkers, Tumor; Cell Adhesion; Cell Cycle Checkpoints; Cell Line, Tumor; Cell Movement; Cell Proliferation; Cell Survival; Male; Mice; Mice, Nude; Neoplasm Invasiveness; ortho-Aminobenzoates; Prostatic Neoplasms; Xenograft Model Antitumor Assays

Survivin is overexpressed in most human cancers, including pancreatic adenocarcinoma. Expression of survivin is regulated by specificity protein (Sp) proteins and related to resistance to radiation therapy. Tolfenamic acid induces Sp protein degradation in several cancer cell lines. The purpose of this study is to investigate whether tolfenamic acid inhibits survivin expression and sensitizes pancreatic cancer cells/tumor to radiotherapy. Panc1 and L3.6pl cells have been used to study the effect of radiation on survivin expression and to investigate the efficacy of tolfenamic acid in enhancing the response to radiation therapy. In addition, an orthotopic model for human pancreatic cancer has been used to confirm the efficacy of tolfenamic acid to enhance tumor response to radiation in vivo. Pancreatic cancer cell lines express variable levels of survivin mRNA/protein, which correlate with their radiosensitivity. Radiation increased survivin promoter activity and protein expression in Panc1 and L3.6pl cells and tolfenamic acid inhibited both constitutive and radiation-induced survivin protein expression and enhanced the response of pancreatic cancer cells to radiation therapy. In vivo studies show that tolfenamic acid enhanced the radiation-induced apoptosis associated with decreased survivin expression in tumors and this correlates with the enhanced response of these tumors to the radiation. Thus, tolfenamic acid significantly enhances pancreatic cancer cells/tumor response to radiation therapy. The underlying mechanism includes tolfenamic acid-induced degradation of Sp proteins, which in tumor decreases expression of the Sp-dependent antiapoptotic protein survivin. These preclinical data suggest that tolfenamic acid has the potential to increase the response of pancreatic adenocarcinoma to radiation therapy.

Topics: Adenocarcinoma; Animals; Apoptosis; Down-Regulation; Gene Expression Regulation, Neoplastic; Humans; Inhibitor of Apoptosis Proteins; Male; Mice; Mice, Nude; Microtubule-Associated Proteins; ortho-Aminobenzoates; Pancreatic Neoplasms; Promoter Regions, Genetic; Radiation Tolerance; Radiation-Sensitizing Agents; Survivin; Tumor Cells, Cultured; Xenograft Model Antitumor Assays