Fig 2: Verteporfin inhibits TAZ/YAP activity in sarcoma cells lines and abrogates colony formation in soft agarVerteporfin reduces colony formation in a dose dependent manner in the HT-1080 a. and SK-LMS-1 cell lines b. Administration of verteporfin results in decreased expression of CTGF (a canonical transcriptional target of the TEAD transcription factors) in a dose dependent manner in both the HT-1080 c. and SK-LMS-1 cell lines d.

Fig 3: YAP and TAZ are associated with increased gradea. TAZ/YAP are only focally and weakly expressed in well-differentiated liposarcoma (grade 1 tumors). b. Increased YAP and TAZ expression in dedifferentiated liposarcoma (grade 2 to 3). c. Graphical representation of YAP and TAZ activation in dedifferentiated liposarcoma (DDLPS) vs. well-differentiated liposarcoma (WDLPS); TAZ is activated to a greater degree in dedifferentiated liposarcoma as compared to well-differentiated liposarcoma (p = 0.0014). d. YAP and TAZ activation levels are low to absent in grade 1 and 2 chondrosarcomas, but present in most (~70-80%) of grade 3 chondrosarcomas e. Graphical representation of YAP and TAZ activation in chondrosarcoma, showing a statistically significant increase of activated YAP and TAZ is grade 3 chondrosarcoma as compared to grade 1/2 chondrosarcomas (YAP, p = 0.0128) and (TAZ, p = 0.0034).

Fig 4: Expression of the Hippo kinases in vitro(A) Immunofluorescence demonstrating constitutive nuclear localization of TAZ and YAP in A204 cells grown to confluence. (B) Western blot demonstrating a loss of expression of Hippo kinases relative to GCT (giant cell tumor) cell line. (C) Quantitative western blot for MST1, MST2 and LATS2 (the most commonly lost kinases) in the SKLMS1, RD, and A204 cell lines and compared to GCT. The SKLMS1, RD, and A204 cell lines showed a stastically significant decrease in expression in MST1 and MST2 as compared to GCT. Of these three lines, only A204 demonstrated a significant decrease in expression of LATS2. Statistical significance determined by two-tailed t-test. * indicates p < 0.05; ** indicates p < 0.01; *** indicates p < 0.001.

Fig 5: Working model of YAP and TAZ activation in sarcomasa. YAP and TAZ have differential effects in different sarcomas as demonstrated in clinical samples and cell lines. YAP and TAZ are constitutively activated (localized within the nucleus) due to silencing of the Hippo pathway b. or activation of still unknown c. upstream pathways. d. The complex between YAP/TAZ and TEAD4 can be inhibited pharmacologically, indicating YAP/TAZ represent therapeutic targets in sarcomas.