Blocking a growth factor receptor cripples cancer growth in a form of T cell leukemia, according to a study published online on August 1 in the Journal of Experimental Medicine
Approximately half of the cases of T cell acute lymphoblastic leukemia (T-ALL) carry genetic mutations in a cellular signaling pathway called Notch, which result in aberrant activation of the cell. A study by Andrew Weng and colleagues at the British Columbia Cancer Agency now shows that activation of the Notch pathway promotes the expression of a receptor for insulin growth factor (IGF-1), which drives the growth and survival of the cancer cells.
Cancer cells with an activated Notch pathway but lacking the IGF-1 receptor had reduced growth in mice, and blocking the receptor with drugs improved their survival. Simply reducing the amount of receptor resulted in the loss of cancer stem cells-the cells responsible for originating and perpetuating the disease. Human T-ALL cells were also found to express IGF-1 receptor, suggesting that blocking the receptor in combination with standard treatment may reduce the risk of disease relapse.