The derivation of OCI-C1p, OCI-C4p, OCI-C5x, and OCI-P5x cells was previously described (16 (link)). OCI-cells were cultured in OCMI-L, a specific growth medium developed for these cells (US Biological, Cat # 506390). The OCI cells are available from the Ince laboratory. The passage number of OCI cells at the time of each experiment was from 40 to 60. TOV21G cells were obtained from ATCC and cultured in 1:1 of Medium 199 (Gibco®) and MCDB105 (Cell Application Inc.) with 15% fetal bovine serum (FBS). RMG1 cells were obtained from JCRB cell bank and maintained in RPMI with 20% FBS. Dicer-substrate small interfering RNAs (dsiRNAs) targeting BRD2, BRD3, BRD4 as well as negative control dsiRNA were purchased from Integrated DNA Technologies. AllStars Hs Cell Death Control siRNA was purchased from QIAGEN. JQ1 (13 (link)), CP203 (13 (link), 17 (link)), CPI0610 (18 (link)), Alpelisib (BYL719) (19 (link)) and MK2206 (20 (link)) were purchased from Selleckchem.