Lasting response by vertical inhibition with Cetuximab and Trametinib in KRAS mutated Colorectal Cancer Patient-derived Xenografts (PDX)

All xenograft models carried an oncogenic KRAS mutation. All mice were treated with cetuximab (25 mg/kg, twice weekly, i.p., Merck) and trametinib (0.5 mg/kg, five subsequent days per week, p.o., Hycultec) to establish response characteristics. Primary resistant PDX tumors (BoC51, 109, 117, and 122) and secondary resistant tumors (BoC2 and BoC56) were harvested at the end of treatment (days 29 to 59). For BoC2 and 56, untreated control Tumors (K) were harvested once tumors reached approx. 1000mm3 in volume.