Espectrophotometric characterization and cytotoxicity of new phthalocyanines derivatives of for treatment of colorectal carcinoma

5^th World Congress on Cancer Therapy

September 28-30, 2015 Atlanta, USA

Cristina Andr�©s Ledesma

University of Salamanca, Spain

Posters-Accepted Abstracts: J Cancer Sci Ther

Abstract :

Colorectal carcinoma is the second leading cause of cancer deaths in the developed world and oxidative stress is a key factor. Photodynamic therapy is being explored as a novel treatment in which photosensitive substances, such as phthalocyanine derivatives are activated by visible light. We have synthesized new phthalocyanine derivatives called PZ. Purpose: To characterize PZs espectrophotometrically to stablish the excitation wavelengths appropriate to activate them and induce death in tumor cells. To evaluate PZ citotoxicity at different doses in colorectal carcinoma HT29 cell line. Methods: Two phthalocyanine derivatives (PZ1 and PZ2, that differ in the presence of saccharide lateral chains) were synthetized and characterized using Shimadzu spectrophotometer UV-1800 and spectrofluorometer RF-5301PC. Doses from 4.2 to 420 g/L were added to HT29 cells (ATCC) for 24 hours. Result: Three absorption peaks were observed in the spectra of PZ1 and PZ2: 340nm, 658nm and 962nm. Excitation at 265nm results in emission in the visible spectrum range. Treatment with PZ1 yields a dose-dependent survival curve ranging from 73% (4,2g/L) to 37% (420 g/L). However, treatment with PZ2 results in a dose-independent 17% cell survival. Conclusion: PZ has toxic effects on cancer cells. Our results suggest that the presence of the lateral chains induce higher mortality. We hypothesize that this effect might be due to a facilitated access to the cell by contact with membranes. Our next aim is to combine PZ treatment with light activation (UV, visible or infrared) while characterizing its subcellular localization and putative sites of therapeutic action.

Biography :

Email: kriss_rubia3@hotmail.com