Supplementary Figure 8: HDAC6 inhibition significantly inhibits tumour growth ARID1A-mutated, but not wildtype, tumours.

(a,b) Luciferase-expressing ARID1A-mutated TOV21G cells were orthotopically transplanted into the ovarian bursa sac of SCID/nude female mice. Tumours were allowed to establish for 14 days before randomized into two groups (n = 6 mice/group). Mice were treated with vehicle control or HDAC6 inhibitor (ACY1215, 50mg/kg) daily for 21 days. Representative images of control and ACY1215 treated mice at the end of treatment (a). Total flux (photons/sec) is graphed at the indicated time points (b). ^∗P = 0.0313. Error bars represent S.E.M. P-value calculated via two-tailed t-test. (c) 6-10-weeks-old Pik3ca^H1047R/Arid1a^flox/flox female mice were intrabursally injected with adenovirus-Cre to induce clear cell ovarian carcinomas. Mice were randomized and treated with vehicle control (n = 5 mice) or ACY1215 (50 mg/kg, n = 4 mice) daily for 21 days. The changes in volumes of tumours formed on the injected ovary were calculated against the contrary side non-injected ovary from the same mice. (d–i) Luciferase-expressing ARID1A-wildtype RMG1 cells were orthotopically transplanted into the ovarian bursa sac of SCID/nude female mouse. Tumours were allowed to establish for 14 days before randomized into two groups (n = 6 mice/group). Mice were treated with vehicle control or HDAC6 inhibitor (ACY1215, 50 mg/kg) daily for 21 days. Representative images of control and ACY1215 treated mice at the end of treatment (d). At the indicated time interval during treatment, mice were imaged for luciferase expression to monitor tumour growth. Total flux (photons/sec) is graphed (e). The weight of tumours dissected from control and ACY1215 treated mice was measured at the end of treatment as a surrogate for tumour burden (f). The number of disseminated tumour nodules was counted in the indicated treatment groups (g). The serial sections of tumours dissected were subjected to immunohistochemical staining for HDAC6, Ki67, cleaved caspase 3 and p53K120Ac (h). Scale bar = 100 μm. Histological score (H-score) was calculated for 5 separate fields from 6 tumours from 6 individual mice from each of the indicated groups (i). Error bars represent mean with S.E.M. P-value calculated via two-tailed t-test. Statistical source data are provided in Supplementary Table 6.