Oxamflatin (Metacept-3) is a potent HDAC inhibitor with an IC₅₀ of 15.7 nM. IC50 & Target: IC50: 15.7 nM (HDAC)^[1] In Vitro: Oxamflatin induces transcriptional activation of junD and morphological reversion in various NIH3T3-derived transformed cell lines. Oxamflatin shows antiproliferative activity against various mouse and human tumor cell lines with drastic changes in the cell morphology. Oxamflatin causes an elongated cell shape with filamentous protrusions as well as arrest of the cell cycle at the G1 phase in HeLa cells. Oxamflatin greatly enhances the transcriptional activity of the CMV promoter in a dose-dependent manner and inhibits intracellular HDAC activity^[1]. Oxamflatin in the nanomolar range induces morphological changes in OVCAR-5 and SKOV-3 ovarian cancer cell lines. Treatment with oxamflatin also leads to decreased cell viability. Oxamflatin is able to significantly inhibit DNA synthesis and cell proliferation^[2]. Oxamflatin can induce E-cadherin expression and also reduce cell viability in the MKN-45 cell line^[3]. In Vivo: Injection of oxamflatin, six times at the dose of 20 mg/kg, exhibits a significant increase in the days of survival (38% of ILS). The ILS of the mice treated with oxamflatin at the dose of 50 mg/kg is calculated to be more than 67% and one mouse survived over 60 days after tumor inoculation. No subsidiary effect, such as body weight loss, is observed at least up to this dose^[1].