Kanser Hücre Hatlarına Karşı Epetraborolün Sitotoksik Aktivitesi

Öz

Amaç: Antibiyotiklerin yeniden konumlandırılması, iyi karakterize edilmiş farmakoforların kanser hücrelerinde korunmuş zayıf noktaları hedeflemesine olanak tanıyan umut verici bir onkoloji stratejisidir. Bu çalışmada, benzoksaborol sınıfı bir lösil-tRNA sentetaz inhibitörü olan epetraborolün (EP) farklı kanser hücre tiplerine karşı sitotoksik potansiyelinin değerlendirilmesi amaçlanmıştır. Yöntemler: EP’nin sitotoksik etkileri; malign mezotelyoma (CARM-L12 TG3), osteosarkom (MG63) ve kolorektal karsinom (HT-29, SW-48 ve 2A3) olmak üzere beş farklı kanser hücre hattında incelenmiştir. Yetmiş iki saatlik maruziyet sonrası doz ve zamana bağlı yanıtları belirlemek amacıyla MTT hücre canlılığı testleri uygulanmıştır. Antibakteriyel aktivite, Escherichia coli’ye karşı minimum inhibitör konsantrasyonun (MİK) belirlenmesiyle doğrulanmıştır. Bulgular: EP, doz ve zamana bağlı olarak anlamlı sitotoksik aktivite göstermiştir. Bileşik, en yüksek etkinliği CARM-L12 TG3 (IC₅₀ = 0.408 ± 1.1 µg/mL) ve MG63 (IC₅₀ = 0.875 ± 1.6 µg/mL) hücre hatlarında sergilerken, kolorektal karsinom hücreleri daha düşük duyarlılık göstermiştir (IC₅₀ > 3 µg/mL). Antibakteriyel testler EP’nin biyolojik aktivitesini doğrulamış ve E. coli için MİK değeri 0.5 µg/mL olarak saptanmıştır. Sonuç: Epetraborol, özellikle mezotelyoma ve osteosarkom gibi mezenkimal kökenli kanserlere karşı güçlü bir sitotoksik potansiyel sergilemektedir. Elde edilen bulgular, EP’nin protein sentez mekanizmasına bağımlı maligniteleri hedefleyen onkolojik yeniden konumlandırma çalışmaları için umut verici bir aday olduğunu göstermektedir.

Anahtar Kelimeler

• Epetraborol (AN3365)
• sitotoksisite
• kanser hücre hatları
• IC₅₀
• benzoksaborol
• MTT

CYTOTOXIC ACTIVITY OF EPETRABOROLE AGAINST CANCER CELL LINES

Öz

Objective: Antibiotic repurposing represents a promising strategy in oncology, utilizing well-characterized pharmacophores to exploit conserved vulnerabilities in cancer cells. This study aimed to evaluate the cytotoxic potential of epetraborole (EP), a benzoxaborole-class leucyl-tRNA synthetase inhibitor, against various cancer cell types. Methods: The cytotoxic effects of EP were assessed in five cancer cell lines: malignant mesothelioma (CARM-L12 TG3), osteosarcoma (MG63), and colorectal carcinomas (HT-29, SW-48, and 2A3). MTT cell viability assays were conducted to determine dose- and time-dependent responses following 72-hour exposure. Antibacterial activity was verified by determining the minimum inhibitory concentration (MIC) against Escherichia coli. Results: EP exhibited significant cytotoxic activity in a dose- and time-dependent manner. The compound showed highest potency against CARM-L12 TG3 (IC50= 0.408 ± 1.1 µg/mL) and MG63 (IC₅₀ = 0.875 ± 1.6 µg/mL) cell lines, while colorectal carcinoma cells were less sensitive (IC50 > 3 µg/mL). Antibacterial testing confirmed EP’s bioactivity, with an MIC value of 0.5 μg/mL against E. coli. Conclusion: Epetraborole demonstrates strong cytotoxic potential, particularly against mesenchymal-derived cancers such as mesothelioma and osteosarcoma. These results suggest that EP is a promising candidate for repurposing in oncology, targeting malignancies dependent on protein synthesis machinery.

Anahtar Kelimeler

• Epetraborole (AN3365)
• cytotoxicity
• cancer cell lines
• IC50
• benzoxaborole
• MTT

Kaynakça

1. Rajaraman R, Guernsey DL, Rajaraman MM, Rajaraman SR. Stem cells, senescence, neosis and self-renewal in cancer. Cancer Cell Int. 2006;6:25. doi:10.1186/1475-2867-6-25.
2. K E Kanady., W U Shipley., A L Zietman., et al. Treatment strategies using transurethral surgery, chemotherapy, and radiation therapy with selection that safely allows bladder conservation for invasive bladder cancer. Semin Surg Oncol. 1997;13(5):359-364. doi:10.1002/(sici)1098-2388(199709 /10)13:5<359::aid-ssu10>3.0.co;2-i.
3. Lordick F, Hacker U. Chemotherapy and Targeted Therapy. In: Imaging of Complications and Toxicity following Tumor Therapy. 2014;3–15.
4. Xia D, Yang X, Liu W, et al. Over-expression of CHAF1A in Epithelial Ovarian Cancer can promote cell proliferation and inhibit cell apoptosis. Biochem Biophys Res Commun. 2017;486(1):191-197. doi:10.1016/j.bbrc.2017.03.026.
5. Pfab C, Schnobrich L, Eldnasoury S, Gessner A, El-Najjar N. Repurposing of Antimicrobial agents for cancer therapy: What do we know? Cancers (Basel). 2021;13(13):3193. doi:10.3390/cancers13133193
6. Karamanolis NN, Kounatidis D, Vallianou NG, et al. Unraveling the anti-cancer mechanisms of antibiotics: Current insights, controversies, and future perspectives. Antibiotics. 2024;14(1):9. doi:10.3390/antibiotics14010009.
7. Bano N, Parveen S, Saeed M, et al. Drug repurposing of selected antibiotics: an emerging approach in cancer drug discovery. ACS Omega. 2024;25:26762–26779. doi:10.1021/acsomega.4c00617.
8. Škrtić M, Sriskanthadevan S, Jhas B, et al. Inhibition of Mitochondrial Translation as a Therapeutic Strategy for Human Acute Myeloid Leukemia. Cancer Cell. 2011;20(5):674–688. doi:10.1016/j.ccr.2011.10.015

9. Herald C, Occur M, Ganslmayer M, et al. Ciprofloxacin induces apoptosis and inhibits proliferation of human colorectal carcinoma cells. Br J Cancer. 2002;86(3):443–448. doi:10.1038/sj.bjc.6600079
10. Gupta PB, Onder TT, Jiang G, et al. Identification of Selective Inhibitors of Cancer Stem Cells by High-Throughput Screening. Cell. 2009;138(4):645–659. doi:10.1016/j.cell.2009.06.034.
11. Das BC, Adil Shareef M, Das S, Nandwana NK, Das Y, Saito M, Weiss LM. Boron-Containing heterocycles as promising pharmacological agents. Bioorg Med Chem. 2022;63:116748. doi:10.1016/j.bmc.2022.116748.
12. Cardenas CA. Review of boron-based compounds: Advancing cancer therapy and beyond. Clin Oncol Case Rep. 2023;6:2–3.
13. Dhawan B, Akhter G, Hamid H, et al. Benzoxaboroles: New emerging and versatile scaffold with a plethora of pharmacological activities. J Mol Struct. 2022;1252. doi:10.1016/j.molstruc.2021.132057
14. Mendes RE, Alley MRK, Sader HS, et al. Potency and spectrum of activity of AN3365, a novel boron-containing protein synthesis inhibitor, tested against clinical isolates of enterobacteriaceae and nonfermentative gram-negative bacilli. Antimicrob Agents Chemother. 2013;57(6):2849-2857. doi:10.1128/AAC.00160-13.
15. Medina MÁ, Márquez J, Núñez de Castro I. Interchange of amino acids between tumor and host. Biochem Med Metab Biol. 1992;48(1):1-7. doi:0.1016/0885-4505(92)90041-V
16. Shikano N, Ogura M, Okudaira H, et al. Uptake of 3-[125I]iodo-α-methyl-l-tyrosine into colon cancer DLD-1 cells: characterization and inhibitory effect of natural amino acids and amino acid-like drugs. Nucl Med Biol. 2010;37(2):197-204. doi:10.1016/j.nucmedbio.2009.10.011
17. Lamb RF. Amino acid sensing mechanisms: An Achilles heel in cancer? FEBS J. 2012;279(15):2624-2631. doi:10.1111/j.1742-4658.2012.08659.x
18. Passarelli MC, Pinzaru AM, Asgharian H, et al. Leucyl-tRNA synthetase is a tumour suppressor in breast cancer and regulates codon-dependent translation dynamics. Nat Cell Biol. 2022;24(3):307-315. doi:10.1038/s41556-022-00856-5.
19. Gao G, Yao Y, Li K, Mashausi DS, Li D, Negi H, et al. A human leucyl-tRNA synthetase as an anticancer target. Onco Targets Ther. 2015;8:2933-2942. doi:10.2147/OTT.S88873.
20. Dibek E, Babayeva A, Sezer Kürkçü M, et al. Bor içeren bazı biyoaktif bileşikler. J Boron. 2020;5(1):29-39. doi:10.30728/boron.604069
21. Ganapathy US, Gengenbacher M, Dick T. Epetraborole is active against mycobacterium abscessus. Antimicrob Agents Chemother. 2021;65(10):e0115621. doi:10.1128/AAC.01156-21.
22. Cummings JE, Lunde CS, Alley MRK, Slayden RA. Epetraborole, a leucyl-tRNA synthetase inhibitor, demonstrates murine efficacy, enhancing the in vivo activity of ceftazidime against Burkholderia pseudomallei, the causative agent of melioidosis. PLoS Negl Trop Dis. 2023;17(11): e0011795. doi:10.1371/journal.pntd.0011795.
23. Abayeva A, Dibek E, Sünnetçi Akkoyunlu D, et al. The effect of epetraborole on the transcriptome and proteome profiles of an Escherichia coli strain overexpressing leuS, Leucyl-tRNA Synthetase. Front Life Sci RT. 2024;5:48–58. doi:10.51753/flsrt.1416938.
24. Dibek E, Sezer M, Akguc N. Genomic library construction of a boron tolerant bacterium in Escherichia coli and selection by boron. Tjmbb. 2017;2:21–29.
25. Babayeva A, Çöl B. Genome-wide Screening of the Escherichia coli Keio Knockout Collection Identifies Genetic Determinants of Epetraborole Hypersusceptibility. Eur J Clin Microbiol Infect Dis. 2025;44(9):2167-2182. doi:10.1007/s10096-025-05183-9.
26. Babayeva A, Dibek E, Kıvrak İ, Çöl B. The cytotoxic effects of Turkish bee venom (Apis mellifera) on selected cancer cell lines. Int J Pept Res Ther. 2024;30(5):53. doi:10.1007/s10989-024-10631-9.
27. Kürkçü MS, Genç D, Çöl B. Caffeic Acid’s Influence on the Viability and Apoptosis of a Diverse Array of Cancer Cell Lines. JARNAS. 2025;11(2):95-106. doi:10.28979/jarnas.1645815
28. Swift ML. GraphPad prism, data analysis, and scientific graphing. J Chem Inf Comput Sci. 1997;37.
29. Saeidnia S. Anticancer Antibiotics. In: New Approaches to Natural Anticancer Drugs. 2014;51–66.
30. Cragg GM, Newman DJ. Natural Products Drug Discovery and Development at the United States National Cancer Institute. In: Drug Discovery and Traditional Chinese Medicine. 2001.
31. Gao Y, Shang Q, Li W, Guo W, Stojadinovic A, Mannion C, Man YG, Chen T. Antibiotics for cancer treatment: A double-edged sword. J Cancer. 2020;11(17):5135-5149. doi:10.7150/jca.47470.
32. Brodersen DE, Clemons WM, Carter AP, et al. The structural basis for the action of the antibiotic’s tetracycline, pactamycin, and hygromycin B, on the 30S ribosomal subunit. Cell. 2000;103. doi:10.1016/S0092-8674(00)00216-6.
33. Kostopoulou ON, Kourelis TG, Mamos P, et al. Insights into the chloramphenicol inhibition effect on peptidyl transferase activity, using two new analogs of the drug. Open Enzyme Inhib. 2011;4:1-10. doi:10.2174/1874940201104010001.
34. Grollman AP. Inhibitors of protein biosynthesis. II. Mode of action of anisomycin. J Biol Chem. 1967;242(13):3226-3233. doi:10.1016/s0021-9258(18)95953-3.
35. Miclau T, Edin ML, Lester GE, et al. Effect of ciprofloxacin on the proliferation of osteoblast-like MG-63 human osteosarcoma cells in vitro. J Orthop Res. 1998;16(4):509-512. doi:10.1002/jor.1100160417.
36. Cao Y, Wu K, Mehta R, et al. Long-term use of antibiotics and risk of colorectal adenoma. Gut. 2018;67(4):672-678. doi:10.1136/gutjnl-2016-313413.
37. Jemal A, Bray F, Center MM, Ferlay J, Ward E, Forman D. Global cancer statistics. American Cancer Society. CA Cancer J Clin. 2011;61(2):69-90. doi:10.3322/caac.20107.
38. Ferlay J, Colombet M, Soerjomataram I, et al. Cancer statistics for the year 2020: An overview. Int J Cancer. 2021;149(4):778-789. doi:10.1002/ijc.33588.
39. Bernstein CN, Eliakim A, Fedail S, et al. World Gastroenterology Organisation global guidelines inflammatory bowel disease: Update August 2015. J Clin Gastroenterol. 2016;50(10):803-818. doi:10.1097/MCG.0000000000000660
40. Nitzan O, Elias M, Peretz A, Saliba W. Role of antibiotics for treatment of inflammatory bowel disease. World J Gastroenterol. 2016;22(3):1078-1087. doi:10.3748/wjg.v22.i3.1078.
41. Wang JL, Chang CH, Lin JW, et al. Infection, antibiotic therapy and risk of colorectal cancer: A nationwide nested case-control study in patients with Type 2 diabetes mellitus. Int J Cancer. 2014;135(4):956-967. doi:10.1002/ijc.28738.
42. Dik VK, van Oijen MGH, Smeets HM, Siersema PD. Frequent use of antibiotics is associated with colorectal cancer risk: Results of a nested case-control study. Dig Dis Sci. 2016;61(1):255-264. doi:10.1007/s10620-015-3828-0.
43. Crockett SD, Nagtegaal ID. Terminology, molecular features, epidemiology, and management of serrated colorectal neoplasia. Gastroenterology. 2019;157(4):949-966.e4. doi:10.1053/j.gastro.2019.06.041.
44. Zhang J, Haines C, Watson AJM, et al. Oral antibiotic use and risk of colorectal cancer in the United Kingdom, 1989-2012: A matched case-control study. Gut. 2019;68(11):1971-1978. doi:10.1136/gutjnl-2019-318593.
45. Esposito G, Gigli S, Seguella L, et al. Rifaximin, a non-absorbable antibiotic, inhibits the release of pro-angiogenic mediators in colon cancer cells through a pregnane X receptor-dependent pathway. Int J Oncol. 2016;49(2):639-645. doi:10.3892/ijo.2016.3550.
46. Zhou Y, Deng Y, Wang J, et al. Effect of antibiotic monensin on cell proliferation and IGF1R signaling pathway in human colorectal cancer cells. Ann Med. 2023;55(1):2166980. doi:10.1080/07853890.2023.2166980.
47. Onoda T, Ono T, Dhar DK, et al. Tetracycline analogues (doxycycline and COL-3) induce caspase-dependent and -independent apoptosis in human colon cancer cells. Int J Cancer. 2006;118(5):1309-1315. doi:10.1002/ijc.21447.
48. Klein MJ, Siegal GP. Osteosarcoma: Anatomic and histologic variants. Am J Clin Pathol. 2006;125(4):555-581. doi:10.1309/UC6K-QHLD-9LV2-KENN
49. de Azevedo JWV, de Medeiros Fernandes TAA, Fernandes JV, et al. Biology and pathogenesis of human osteosarcoma. Oncol Lett. 2020;19(2):1099-1116. doi:10.3892/ol.2019.11229
50. Duewelhenke N, Krut O, Eysel P. Influence on mitochondria and cytotoxicity of different antibiotics administered in high concentrations on primary human osteoblasts and cell lines. Antimicrob Agents Chemother. 2007;51(1):54-63. doi:10.1128/AAC.00729-05.