(-)-Viriditoxin is a mycotoxin originally isolated from A. viridinutans that has antibacterial and antiproliferative activity. It is active against methicillin-sensitive and -resistant S. aureus (MSSA and MRSA, respectively), tetracycline-sensitive and -resistant Staphylococcus, vancomycin-sensitive and -resistant Enterococcus, and penicillin-sensitive and -resistant S. pneumoniae (MICs = 2-32 μg/ml). (-)-Viriditoxin is also active against fish pathogens, including S. iniae and S. parauberis (MICs = 0.16-0.21 μg/ml). It inhibits polymerization and the GTPase activity of E. coli FtsZ, a tubulin-like GTPase involved in bacterial cell division (IC50s = 8.2 and 7 μg/ml, respectively). (-)-Viriditoxin inhibits proliferation of human DU145, LNCaP, and PC3 prostate cancer cells (IC50s = 5.36, 0.63, and 7.6 μM, respectively) . It is also toxic to mice (LD50 = 2.8 mg/kg, i.p.).
Darinaparsin is a dimethylated arsenic linked to glutathione. It is cytotoxic to DU145, LNCaP, and PC3 prostate cancer cells (IC50s = 5-10 µM) and patient-derived primary prostate cancer cells (IC50s = 2.5-20 µM), as well as Jurkat T cell lymphoma and L540 Hodgkin lymphoma cells (IC50s = 2.7 and 1.3 µM, respectively). [1][2] It decreases the tumor-initiating subpopulation in DU145 and PC3 cells and halts the cell cycle in the G2 M phase. Darinaparsin decreases transcription of Gli-2, a transcription factor that mediates Sonic hedgehog signaling, when used at a concentration of 1.5 but not 3 µM. It decreases SHP1 phosphatase activity and increases ERK phosphorylation. [2] Darinaparsin reduces tumor growth in DU145 and PC3 prostate cancer mouse xenograft models when administered at a dose of 100 mg kg every other day.[1]
CAY10744 is a topoisomerase II-α poison.1 It inhibits topoisomerase II-α by 78.9% when used at a concentration of 20 μM. CAY10744 is selective for topoisomerase II-α over topoisomerase I providing 100 and 0% inhibition, respectively, at 100 μM. It inhibits proliferation of HCT15 colon, T47D breast, DU145 prostate, and HeLa cervical cancer cells (IC50s = 0.014, 0.00267, 0.072, and 2.46 μM, respectively). CAY10744 induces apoptosis in T47D cells when used at concentrations of 10 and 30 μM. CAY10744 (12 mg/kg per day) reduces tumor growth in an MDA-MB-231 orthotopic mouse model of breast cancer. |1. Kadayat, T.M., Park, S., Shrestha, A., et al. Discovery and biological evaluations of halogenated 2,4-diphenyl indeno[1,2-b]pyridinol derivatives as potent topoisomerase IIa-targeted chemotherapeutic agents for breast cancer. J. Med. Chem. 62, 8194-8234 (2019).
Nanangenine F is a drimane sesquiterpene fungal metabolite that has been found inA. nanangensis.1It is active againstB. subtilis(IC50= 78 μg ml) and cytotoxic to NS-1, DU145, and MCF-7 cancer and NFF non-cancerous cells (IC50s = 49, 95, 49, and 84 μg ml, respectively). 1.Lacey, H.J., Gilchrist, C.L.M., Crombie, A., et al.Nanangenines: Drimane sesquiterpenoids as the dominant metabolite cohort of a novel Australian fungus, Aspergillus nanangensisBeilstein J. Org. Chem.152631-2643(2019)