Synthesis and evaluation of in vitro cytotoxic effects of triazol/spiroindolinequinazolinedione, triazol/indolin-3-thiosemicarbazone and triazol/thiazol-indolin-2-one conjugates

Abstract

Purpose: Cancer as one of the major diseases with high mortality rates threats human life in the world. Subsequently, the design new potent anticancer agents has attracted much attention in the area of synthetic and medicinal chemistry. In this study, new triazol-linked spiroindolinequinazolinone, thiazol-oxindole and oxindole-thiosemicarbazone conjugates were synthesized and evaluated for their in vitro cytotoxic activity toward different cancer lines.

Methods: Some new triazol-linked oxindoles and spirooxindoles conjugates were synthesized. The synthesized compounds were tested for their in vitro cytotoxic activity toward cancer lines including A375, PC3, LNCaP, MDA MB231 and normal cells HDF (human dermal fibroblast).

Results: Among all synthesized compounds, the triazol-linked oxindol-thiosemicarbazone conjugate 10b showed the highest cytotoxic activity against different cancer cells. By using quantitative real time PCR (qRT-PCR), it was found that 10b is able to induce apoptosis by alteration of Bax, Bcl2 balance (i.e. by up regulation of Bax and down regulation of Bcl-2 mRNA expression levels). The DAPI staining was used to show the death of cancer cells in the presence of 10b. Interestingly, 10b suppressed the migration of LNCaP cancer cells by up-regulation of epithelial markers (E-cadherin) and down-regulation of mesenchymal markers (vimentin).

Conclusion: Our findings revealed that the compound 10b may be a new potent candidate with multiple biological activities to design therapeutic agents against different cancers. Synthesis and evaluation of in vitro cytotoxic effects of triazol/spiroindolinequinazolinedione, triazol/indolin-3-thiosemicarbazone and triazol/thiazol-indolin-2-one conjugates.

Keywords: Anticancer activity; Apoptosis; Isatin; Oxindole containing thiazole; Spiroindolinequinazoline-dione; Spirooxindole containing triazole.

Synthesis and evaluation of in vitro cytotoxic effects of triazol/spiroindolinequinazolinedione, triazol/indolin-3-thiosemicarbazone and triazol/thiazol-indolin-2-one conjugates.

Fig. 1

Design of target molecules based on reported isatin-based molecules with cytotoxic potential

Scheme 1

Synthesis of 1,2,3-triazol/spiro[indoline-3,2′-quinazoline]-diones 6

Scheme 2

Synthesis of triazol-linked thiazole-oxindole conjugates 9

Fig. 2

Inverted fluorescent microscopy images of chromatin damages occurrence in the nucleus of treated cells with 10b compound and DMSO (1%), which have been stained with DAPI in MDA-MB 231, A375, LNCaP, and PC3 cancer cell lines. The experiments were performed three times (original microscope magnification, 40X, Scale bar, 10 μm)

Fig. 3

(a), (b): In treated LNCaP cells with 10b compound (as sample) and no treated cells (as control), relative expression of Bax mRNA and relative expression of Bcl-2 mRNA were shown. Data represent mean ± SD of three independent experiments. p < 0.05 was considered to be statistically significant

Fig. 4

Effects of compounds 10b on the migration of LNCaP cells in different time (0 and 24 h after treatment; concentration of 10b compound was 29.23 μM). Images were obtained using phase-contrast microscopy. Scale bars represent 50 μm

Fig. 5

(a): Schematic model of epithelial-mesenchymal transition (EMT). (b, c): Relative expression of E-cadherin and Vimentin mRNAs as two potential markers of EMT in treated LNCaP cells with 10b compound (compared to control) were shown. Data represent mean ± SD of three independent experiments. p < 0.05 was considered to be statistically significant