Influence of c-Myc and bcl-2 CO-expression on Proliferation, Apoptosis and Survival in CHO Cultures

Abstract

Under the constitutive control of c-Myc over-expression the CHO cultures showed an increase in growth rate and maximum cell number accompanied by a similar decrease in specific glucose consumption rate. Additionally overexpression of c-Myc appeared to induce morphological transformation and partial anchorage-independence. Although, the c-myc transfected cell line exhibited apoptosis at much lower rates than it is widely reported and associated with the over-expression of c-Myc, it was nevertheless apparent that c-Myc was responsible for the induction of higher apoptotic rates when compared with the control cell line. Hence, the anti-apoptotic gene bcl-2 was also used to transfect the c-Myc CHO cell line, in order to reduce cell death. Over-expression of both oncoproteins resulted in a cell line that exhibited higher proliferation rates and maximum cell numbers, with a decrease in apoptosis when compared to the parental cell line.