MKC-1 is an orally available cell cycle inhibitor with downstream targets that include tubulin and the importin-β family. MKC-1 has shown broad antitumor activity in preclinical models. MKC-1 and its metabolites inhibit tubulin polymerization, blocking the formation of the mitotic spindle, which may result in cell cycle arrest at the G2/M phase and apoptosis. In addition, this agent has been shown to inhibit the activities of the oncogenic kinase Akt, the mTOR pathway, and importin-beta, a protein essential to the transport of other proteins from the cytosol into the nucleus. MKC-1 had been in phase II clinical trials for the treatment of ovarian cancer, endometrial cancer, pancreatic cancer and breast cancer. This compound was originally discovered by Roche, then licensed to EntreMed (now CASI Pharmaceuticals) the exclusive worldwide rights to develop and commercialize. However, no recent development has been reported.

PD 173074 is a potent ATP-competitive inhibitor of fibroblast growth factor receptor 1 and 3. PD173074 is also an effective inhibitor of FGFR2, FGFR4, and VEGFR2. Compared to FGFR1, PD173074 weakly inhibits the activities of Src, InsR, EGFR, PDGFR, MEK, and PKC with 1000-fold or greater IC50 values. PD173074 inhibits autophosphorylation of FGFR1 and VEGFR2 in a dose-dependent manner with IC50 of 1-5 nM and 100-200 nM, respectively. PD173074 specifically inhibits FGF-2-mediated effects on proliferation, differentiation, and MAPK activation in oligodendrocyte (OL) lineage cells. PD173074 treatment potently reduces the viability of FGFR3-expressing KMS11 and KMS18 cells. Inhibition of aFGF-stimulated MM cell growth by PD173074 is highly correlated with the expression of FGFR3. PD173074 treatment completely abolishes NIH 3T3 transformation mediated by Y373C FGFR3 but not by Ras V12, demonstrating that PD173074 specifically targets FGFR3-mediated cell transformation and lacks nonspecific cytotoxic effect. Administration of PD173074 at 1 mg/kg/day or 2 mg/kg/day in mice can effectively block angiogenesis induced by either FGF or VEGF in a dose-dependent manner with no apparent toxicity. PD173074 inhibits in vivo growth of mutant FGFR3-transfected NIH 3T3 cells in nude mice. Inhibition of FGFR3 by PD173074 delays tumor growth and increases survival of mice in a KMS11 xenograft myeloma model. In the H-510 xenograft, oral administration of PD173074 blocks tumor growth similar to that seen with single-agent cisplatin administration, increasing median survival compared with control sham-treated animals. In H-69 xenografts, PD173074 induces complete responses lasting >6 months in 50% of mice. These effects are correlated with increased apoptosis in excised tumors, but not a consequence of disrupted tumor vasculature. PD173074 seems to be discontinued in the preclinical development stage, and no clinical data are available currently.

Pentosan polysulfate sodium (brand name ELMIRON) is a low molecular weight heparin-like compound. It has anticoagulant and fibrinolytic effects and is indicated for the relief of bladder pain or discomfort associated with interstitial cystitis. The mechanism of action of pentosan polysulfate sodium in interstitial cystitis is not known but was discovered, that it t binds Fibroblast growth factors (FGFs) as well as other heparin-binding growth factors.

Pentosan polysulfate sodium (brand name ELMIRON) is a low molecular weight heparin-like compound. It has anticoagulant and fibrinolytic effects and is indicated for the relief of bladder pain or discomfort associated with interstitial cystitis. The mechanism of action of pentosan polysulfate sodium in interstitial cystitis is not known but was discovered, that it t binds Fibroblast growth factors (FGFs) as well as other heparin-binding growth factors.