SOCS2 and in situ carcinoma: Supplementary Figure S3(B) shows the in vitro release profile of CIS, with a rapid and nearly complete extent of release of CIS from all free CIS groups (CIS2, DTX2/CIS2, DTX2/CIS1, and DTX1/CIS2) within 3 h in PBS media, whereas the initial release of CIS from PLOs was fast but with less CIS released.