Why Is Cancer Therapy Such a Difficult and Often Intractable Effort? Cancer Genome Landscapes. Science, Vol. 339, March 29, 2013, pp 1546 – 1548 Bert Vogelstein, Nickolas Papadopoulos, Victor Velculescu, Shibin Zhou, Luis Diaz, Kenneth W. Kinzler Howard Hughes Medical Institute at Johns Hopkins Kimmel Cancer Center, Baltimore VogelsteinScience15Apr13.ppt Updated: April 15, 2013 Number of somatic mutations associated with cancers in patients From 5 or 10 to 130 to 700 mutations per tumor (Insertions & deletions) (Single base substitutions) Signaling Pathways Affected In Cancers Pathway Anomalies in Progression in Colo-Rectal Cancer The RAS Pathway as a representative signaling pathway affected by cancer mutations and approaches to therapy based on RAS pathway anomalies RTK = receptor tyrosine kinase