טכניון מכון טכנולוגי לישראל
הטכניון מכון טכנולוגי לישראל - בית הספר ללימודי מוסמכים  
M.Sc Thesis
M.Sc StudentGrafi-Cohen Meital
SubjectExpression of DRG - 1 Gene on Human Colorectal Cancer
DepartmentDepartment of Medicine
Supervisors Professor Aaron Lerner
Assistant Professor Fuad Fares


Abstract

Drg-1 is a cytoplasmic protein involved in stress, hormone responses, cell growth and differentiation. Drg-1 expression is upregulated by many agents, such as reducing agents and DNA damaging agents.

The objective of the present study was to investigate the expression of Drg-1 gene in human colorectal cancer cells (HCT-116, HT-29 and Colo-320) following treatment with apoptotic factors: Arsenic trioxide (As), Camptothecin (CAM) and 3,3`-diindolylmethane (DIM).      

The effects on cell viability and apoptosis was tested by XTT assay and DNA fragmentation and morphological changes, respectively. The expression of Drg-1 gene was detected by RT-PCR and Real Time PCR following preparation of cDNA  from control and treated cells.

Our results indicated that Drg-1 cDNA sequence in all three cell lines was found identical to the sequence of the gene bank (NCBI).

Treatment of the cells with apoptotic factors significantly inhibit the viability of all three cell lines in a time and dose dependent manner. The decrease in cell viability is mediated through the induction of apoptosis.

Exposure of the cell lines to the apoptotic factors, resulted in a significant increase in Drg-1 expression compared to control cells. In addition, Alkaline phosphatase activity was significantly increased in poorly and moderately differentiated colorectal cells (HT-29 and Colo-320). These results may indicate that treatment with apoptotic factors induce differentiation in the cells. Therefore, inducing Drg-1 expression in poorly and moderately differentiated cells could be important for developing new treatment strategies of human colorectal cancer.