Research Paper Volume 13, Issue 3 pp 3886—3897

Praja2 suppresses the growth of gastric cancer by ubiquitylation of KSR1 and inhibiting MEK-ERK signal pathways

Praja2 promoted ubiquitylation of KSR1. (A) HA-ubiquitin and Flag- praja2 or Flag-mut-praja2 was transfected into HEK293 cells. IP analysis for the relation between praja2 and KSR1. (B) Praja2 or si-praja2 or its NC was transfected into MKN-45 cells, and qRT-PCR analysis for the expression of KSR1. (C) Praja2 or NC was transfected into MKN-45 cells with or without the presence of MG132. Western blot was used to detect praja2, KSR1, MEK, p-MEK, ERK and p-ERK protein level. (D) si-praja2 or si-NC was transfected into MKN-45 cells, and western blot for the expression of praja2, KSR1, MEK, p-MEK, ERK and p-ERK protein. (E) CHX assay was used to determine the role of praja2 on KSR1 stability. (F, G). The expression of praja2 in normal and cancer tissues was detected by qRT-PCR and western blot. (H) IHC for praja2 in normal and cancer tissues of GC. Scale bar, 40 μm.

Figure 4. Praja2 promoted ubiquitylation of KSR1. (A) HA-ubiquitin and Flag- praja2 or Flag-mut-praja2 was transfected into HEK293 cells. IP analysis for the relation between praja2 and KSR1. (B) Praja2 or si-praja2 or its NC was transfected into MKN-45 cells, and qRT-PCR analysis for the expression of KSR1. (C) Praja2 or NC was transfected into MKN-45 cells with or without the presence of MG132. Western blot was used to detect praja2, KSR1, MEK, p-MEK, ERK and p-ERK protein level. (D) si-praja2 or si-NC was transfected into MKN-45 cells, and western blot for the expression of praja2, KSR1, MEK, p-MEK, ERK and p-ERK protein. (E) CHX assay was used to determine the role of praja2 on KSR1 stability. (F, G). The expression of praja2 in normal and cancer tissues was detected by qRT-PCR and western blot. (H) IHC for praja2 in normal and cancer tissues of GC. Scale bar, 40 μm.