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Published on: July 25, 2011
Cytotoxic activity of benzothiepins against human oral tumor cell lines
Y Sugita1, H Hosoya, K Terasawa
1Faculty of Pharmaceutical Sciences, Josai University, Sakado, Saitama, Japan.
Abstract:
A total of 11 newly synthesized benzothiepins and structurally-related compounds were investigated for cytotoxic activity against both normal and tumor cells. All these compounds showed higher cytotoxic activity against three human oral tumor cell lines (HSC-2, HSC-3, HSG) than against normal human gingival fibroblast (HGF), suggesting tumor-specific cytotoxic action. In general, 3,4-dihydro-1-benzothiepin-5(2H)-ones [1-6] showed higher cytotoxic activity than 2,3-dihydro-1-benzothiepins [7-11]. Compounds 4 (4-bromo-3,4-dihydro-2-(2-oxo-2-phenylethyl)-1-benzothiepin-5(2H)-one), 5 (4-bromo-3,4-dihydro-2-(2-oxopropyl)-1-benzothiepin-5(2H)-one) and 6 (4-bromo-3,4-dihydro-2-[1-(methoxycarbonyl)-1-methylethyl]-1-benzothiepin-5(2H)-one), showed higher cytotoxic activity than compounds 1, 2 and 3, respectively, which had Cl instead of Br at C-4 position. Agarose gel electrophoresis demonstrated that these compounds induced large DNA fragments in oral tumor cells, whereas they produced smear pattern of smaller DNA fragments in human promyelocytic leukemia cells HL-60. These data suggest the medicinal efficacy of benzothiepins.
Insights
Newly synthesized benzothiepins show promising tumor-specific cytotoxic activity against oral cancer cell lines. These compounds induce DNA damage in tumor cells, suggesting potential medicinal efficacy for cancer treatment.
Area of Science:
- Medicinal Chemistry
- Pharmacology
- Cancer Biology
Background:
- Benzothiepins are a class of heterocyclic compounds with potential biological activities.
- Investigating novel benzothiepin derivatives for therapeutic applications is an active area of research.
- Cytotoxic agents targeting cancer cells while sparing normal cells are highly sought after.
Purpose of the Study:
- To synthesize and evaluate the cytotoxic activity of novel benzothiepin derivatives.
- To determine the tumor-specific cytotoxic potential of these compounds against oral cancer cell lines.
- To elucidate the mechanism of cell death induced by these benzothiepins.
Main Methods:
- Synthesis of 11 novel benzothiepin and related compounds.
- In vitro cytotoxic assays against human oral tumor cell lines (HSC-2, HSC-3, HSG) and normal human gingival fibroblast (HGF).
- Agarose gel electrophoresis to analyze DNA fragmentation patterns in treated cells.
Main Results:
- All 11 compounds exhibited higher cytotoxicity against oral tumor cell lines compared to normal fibroblasts.
- 3,4-dihydro-1-benzothiepin-5(2H)-ones demonstrated greater activity than 2,3-dihydro-1-benzothiepins.
- Brominated compounds (4, 5, 6) showed enhanced cytotoxicity compared to their chlorinated counterparts (1, 2, 3).
- Compounds induced large DNA fragments in oral tumor cells and smear patterns in HL-60 cells.
Conclusions:
- Benzothiepin derivatives possess significant tumor-specific cytotoxic activity.
- The substitution pattern, particularly the presence of bromine, influences cytotoxic potency.
- The observed DNA fragmentation suggests a mechanism of action involving DNA damage, supporting their medicinal efficacy.
