The invention concerns the field of protein production and cell culture technology. It describes a method of producing a heterologous protein of interest in a cell comprising a. Increasing the expression or activity of a secretion enhancing gene, and b. Increasing the expression or activity of an anti-apoptotic gene, and c. Effecting the expression of said protein of interest, whereby the secretion enhancing gene is a gene encoding a protein whose expression or activity is induced during one of the following cellular processes: plasma-cell differentiation, unfolded protein response (UPR), endoplasmic reticulum overload response (EOR).