Fig. 2
From: ErbB4 promotes malignant peripheral nerve sheath tumor pathogenesis via Ras-independent mechanisms
Loss of ErbB4 in human and mouse MPNST cells inhibits proliferation and survival. a Compared to non-targeting controls, erbB4 knockdown in cells had a decrease in cellular proliferation. b Immunoblots demonstrating reduced erbB4 expression in low erbB4 expressing cells (T265-2c, S462) and high expressing cells (MPNST642) cells infected with erbB4 shRNAs relative to cells infected with a non-targeting control. **, p-value≤0.01; ***, p-value≤0.001; ****, p-value≤0.0001. c Representative erbB4 immunostaining of P0-GGFβ3;Trp53+/−;Erbb4flox/flox GEM mouse tumors showing erbB4 positivity compared to isotype matched negative controls (h). These representative erbB4 immunostains also show punctate membranous staining, with immunoreactivity present in almost all tumor cells (4+ staining). d) Kaplan-Meier survival curve of /flox mice shows that these animals survive an average of 210 days, similar to the parent line P0-GGFβ3;Trp53+/− mice. e) Like their parent line, P0-GGFβ3;Trp53+/−;Erbb4flox/flox mice develop hypercellular neoplasms comprised of atypical spindled cells with numerous mitotic figures. As in human MPNSTs, these tumors are also immunoreactive for both S100β (f) and nestin (g). h Isotype-matched negative control for erbB4 staining of mouse tumors. i Representative infection efficiency of UBI MPNST cell lines. MPNSTs with intact Erbb4 alleles (control, non-recombined) have a spindled morphology similar to that of wild-type Schwann cells, whereas knockout cells (Cre) are more ameboid. Nuclear blebbing was evident in a subset of Erbb4-ablated tumor cells (arrow). Images were imaged at 40X on Brightfield and GFP channels. Infected cells are represented on the green channel due to GFP target sequence in the adenovirus. j, k Decreased cellular viability (j) and proliferation (k) was observed in the Erbb4 knockout cells (Cre) compared to the control cells from three independent tumor cultures. *, p-value≤0.05; ****p-value≤0.0001 for comparisons of recombined (Erbb4 -) with non-recombined (Erbb4+) alleles. Red channel (Alexa 565, erbB4). Blue channel (Hoechst, nuclei)