Investigation of flow cytometry analysis linear and cyclic analogues of Longicalycinin A on cancerous cells HepG2 and HT-29

In this work, cyclic peptide analogues of Longicalycinin A, known as a natural cyclopeptide anticancer agent, have been designed and successfully synthesized by solid phase methodology of Fmoc / t-Bu. 2-chlorotrityl chloride resin (2-CTC) was used as solid support. The synthesized linear (Ot-Bu) Longicalycinin A analogues were cleavaged by the method of partial cleavage for the separation of the solid phase. Macrocyclization of linear (Ot-Bu) Longicalycinin A analogues were done by coupling reagent and then the final deprotection were done on cyclic (Ot-Bu) Longicalycinin A analogues by treatment of TFA 95% and scavengers to achieve cyclic Longicalycinin A analogues. In order to further examine structural basis of Longicalycinin A with the anticancer activity, some liner and cyclic Longicalycinin A peptide analogues were synthesized, using solid-phase peptide synthesis strategy, and their effects as anti-neoplastic agents were examined on cancer cell lines of HepG2 (Human Liver Cancer Cell Line) and HT-29 (Human Colorectal Adenocarcinoma Cell Line) using flow cytometry analysis. Flow cytometry analysis was determined by analytical DNA flow cytometry. HepG2 and HT-29 cells were harvested and adjusted to 104 cells/mL and then incubated for 6h with 10μg/mL of linear and cyclic peptides. The signals obtained in H-1 area mean that PI was able to enter the cells and bind to DNA and so apoptosis has occurred, whereas, the signals appeared in H-2 area indicate that the cancerous cells treated with linear and cyclic peptides remained intact and so no apoptosis has happened.

کلیدواژه ها:

Longicalycinin A ، Macrocyclization ، Anticancer ، Apoptosis ، 2-Cholorotrityl chloride resin