Table 3.

HDAC inhibition of human ovarian cancer cells leads to increased expression of the mAb 376.96 defined B7-H3 epitope.^a

	Number of B7-H3 binding sites/cell (×104)		Entinostat/control ratio
	Control	Entinostat
Adherent Hey-A8	6.54	30.8b	4.71
CIC Hey-A8	6.07	22.0b	3.62
Adherent ES-2	9.48	55.3c	5.83
CIC ES-2	10.4	27.7c	2.66
Adherent SKOV3.ip1	16.7	25.1c	1.50
CIC SKOV3.ip1	19.7	38.3c	1.94
Adherent SKOV3-TR	24.4	40.0c	1.64
CIC SKOV3-TR	13.7	27.7c	2.02

^aScatchard results from binding assays with ^99mTc-376.96 and ovarian cancer cell lines cultured with or without entinostat for 3 days. At 24 h after seeding ovarian cancer cell lines in culture as adherent monolayers (Adherent) or as non-adherent tumorspheres with enriched CIC characteristics (CIC), vehicle (control) or entinostat at the indicated concentration was added to the cells for 3 days. After the 3-day treatment period, adherent monolayers or dissociated CICs in suspension were incubated with dilutions of ^99mTc-376.96 with or without unlabeled mAb 376.96 as a blocking agent for 1 h at 37 °C in Scatchard cell binding assays. The data were analyzed as previously described to determine the number of binding sites per cell [25].

^b1 μM entinostat

^c2.5 μM entinostat.