0.01 0.1 1 10 100 1000-1.0

-0.5

0.0

0.5

p-ERK(T202/Y204)

p-EGFR(T1068)

p-FGFRs(Y653/654)

p-FRS2(Y436)

No Signal

p-RSK3(T356/S360)

Tubulin

A B

C

D

E F

Supplemental Fig. 4. (A) Immunoblot of p-RSK3 and qPCR for DUSP6 from MIA PaCa-2 xenografts collected 3 hours after the last dose from Fig 5C. (B) Immunoblot for the designated proteins from MIA PaCa-2 cells grown in 2D, 3D and from in vivo xenografts without compound treatment. Protein loading amount was normalized and verified by tubulin loading control. Each separate column represents an individual treated tumor. (C) Dependency of MET by DRIVE pooled shRNA screen (y axis, ATARIS Quantile score of less than -0.5 indicates a significant effect) and expressionof HGF (x-axis) by RNAseq in pancreatic cancer cell lines in CCLE (n=21). (D) Immunoblot of p-RSK3 and qPCR for DUSP6 from KP4 xenografts collected 3 hours after the last dose from Fig 5E.Protein loading amount was normalized and verified by tubulin loading control. Each separate columnrepresents an individual treated tumor (E) Immunoblot for the designated proteins from KP4 cells grown in 2D, 3D and from in vivo xenografts without compound treatment (F) Schematic of RTK-SHP2signaling highlighting that SHP2 acts downstream of one or more activated RTKs to elicit downstream signaling in KRAS mutant and also additional SHP2-specific, non-MAPK signaling. SHP2 inhibition bySHP099 can serve as a surrogate for cancers where KRAS mutant cancers are dependent on upstreamRTKs.