Clotam enhances anti-proliferative effect of vincristine in Ewing sarcoma cells

Abstract

Objective: Current therapeutic strategies used in Ewing sarcoma (ES) especially for relapsed patients have resulted in modest improvements in survival over the past 20 years. Combination therapeutic approach presents as an alternative to overcoming drug resistance in metastatic ES. This study evaluated the effect of Clotam (Tolfenamic acid or TA), a small molecule and inhibitor of Specificity protein1 (Sp1) and survivin for sensitizing ES cell lines to chemotherapeutic agent, Vincristine (VCR). Methods: ES cells (CHLA-9 and TC-32) were treated with TA or VCR or TA+VCR (combination), and cell viability was assessed after 24/48/72 hours. Effect of TA VCR or TA +VCR treatment on cell cycle arrest and apoptosis were evaluated using propidium iodide cell cycle assay and Annexin V flow cytometry respectively. The apoptosis markers, Caspase 3/7 (activity levels) and cleaved-PARP (protein expression) were measured. Cardiomyocytes, H9C2 were used as non-malignant cells. Results: While, all treatments caused time-and dose-dependent inhibition of cell viability, interestingly, combination treatment caused significantly higher response (~ 80% inhibition, p< 0.05). Cell viability inhibition was accompanied by inhibition of Sp1 and Survivin. TA+VCR treatment significantly (p< 0.05) increased Caspase 3/7 activity which strongly correlated with upregulated c-PARP level and Annexin V staining. Cell cycle arrest was observed at G0/G1 (TA) or G2/M (VCR and TA+VCR). All treatments did not cause cytotoxicity in H9C2 cells.

Combination of clotam and vincristine enhances anti-proliferative effect in medulloblastoma cells

“…The combination of TA and VCR did not induce any cytotoxic effect in non-cancerous astrocyte cells, serving the purpose of this preliminary study. Recently, we demonstrated that TA and VCR combination did not induce toxicity in cardiomyocytes (H9C2 cells) at the concentrations that inhibited Ewing sarcoma cancer cell growth by 70%(Shelake et al, 2019).…”

Survivin as a biological biomarker for diagnosis and therapy

“…Tolfenamic acid (TA) has been shown anticancer activity in several cancer models, inhibiting both tumor growth and angiogenesis. As a small molecule inhibitor, it induces the degradation of specificity proteins (Sps), leading to a decrease in expression of SVN in various in vitro and in vivo tumor settings such as pancreatic cancer cells [93,94], human medulloblastoma (MB) cell lines, a mouse xenograft model [95], Ewing sarcoma (ES) cells [96], and colon cancer cells [97]. Though these findings point to the use of TA as a potential cancer treatment, a clinical trial of TA in pancreatic cancer in 2014 was withdrawn without a published reason (NCT02159248).…”

Photolysis of tolfenamic acid in aqueous and organic solvents: a kinetic study

“…It is used to treat various pain-related ailments in humans and animals. 1,2 Recently, its anti-Alzheimer effect 3–8 and anticancer activity against various cancers have also been identified and reported by many workers, 9–26 which have significantly increased its clinical importance.…”

“…It is used to treat various pain-related ailments in humans and animals. 1,2 Recently, its anti-Alzheimer effect [3][4][5][6][7][8] and anticancer activity against various cancers have also been identied and reported by many workers, [9][10][11][12][13][14][15][16][17][18][19][20][21][22][23][24][25][26] which have signicantly increased its clinical importance. TA (2-[(3-chloro-2-methylphenyl)amino]benzoic acid) is structurally similar to aminobenzoic acids and contains an amine group that is attached to the two benzoic acid rings (Fig.…”