Cover
Vol. 4 No. 1 (2026)

Published: June 1, 2026

Pages: 285-293

Research Article

Selective Cytotoxic Activity of a 5-BromoIndole Carbothioamide (BTIC) Against Human Cancer Cell Lines

Salar A. Fakhri 1 Abdulkareem Hameed Abd 1 Alaa H. Abbas 2
1 Department of Pharmacology, College of Medicine, Al-Nahrain University, Baghdad, Iraq.
2 Diwaniyah Health Directorate.Iraq
History
  • Received: May 12, 2026
  • Accepted: May 22, 2026
  • Available Online: June 1, 2026

Abstract

Background A major limitation is the low selectivity of conventional chemotherapeutic agents, which results in severe toxicity on non-malignant tissues. Scaffolds based on indole have recently been identified as interesting new anticancer candidates but selective cytotoxicity continues to be a key target. Objective The goal of this study was to determine the cytotoxic and specific anticancer effects of a novel 5-bromo-indole-derived carbothioamide (BTIC) on several malignant and non-cancerous cell lines. Methods After a 48-hour treatment, BTIC's antiproliferative effectiveness against human breast cancer (MCF-7), lung cancer (A549), & normal endothelium (HUVEC) cell lines was evaluated using the MTT assay. Data shown as dose-response curves were subjected to nonlinear regression analysis to determine IC50 values. Preferential cytotoxicity was evaluated using the selectivity index (SI). Results In every cell line examined, BTIC had a cytotoxic impact; furthermore, this toxicity was concentration-dependent. This compound exhibited the most powerful activity against A549 cells (IC50 = 3.5 µg/mL), followed by MCF-7 cells IC50 (5.4 µg/mL), and significant cytotoxicity was recorded in HUVEC cells (IC50 = 10.4 µg/mL). A selective cytotoxicity on cancer cells was suggested by these reported SI values (2.97 and 1.93 for A549 and MCF-7, respectively). Conclusion BTIC was also a lead chemical with potent anticancer action against lung cancer cells in vitro, which exhibited high specificity. Therapeutic translation requires additional mechanistic and in vivo studies.

Keywords

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