unfolded

Thapsigargin is a natural product, an inhibitor of sarcoplasmic/endoplasmic reticulum Ca2+ ATPase (SERCA) and an endoplasmic reticulum stress inducer. Thapsigargin increases cytoplasmic calcium concentration by blocking the ability of cells to pump calcium into the sarcoplasmic and endoplasmic reticulum.

Guanidine hydrochloride (Aminoformamidine Hydrochloride) is a strong organic base existing primarily as guanidium ions at physiological pH. It is found in the urine as a normal product of protein metabolism. It is also used in laboratory research as a protein denaturant.

(-)-Epigallocatechin, the predominant flavonoid in green tea, possesses the unique ability to attach to unfolded native polypeptides, thereby inhibiting their transformation into amyloid fibrils.

Nemorosone is a polycyclic polyprenylated acylphloroglucinol (PPAP) originally isolated from C. rosea that has antiproliferative properties.1 Nemorosone inhibits growth of NB69, Kelly, SK-N-AS, and LAN-1 neuroblastoma cells (IC50s = 3.1-6.3 μM), including several drug-resistant clones, but not MRC-5 human embryonic fibroblasts (IC50 = >40 μM).2 It increases DNA fragmentation in LAN-1 cells in a dose-dependent manner, and decreases N-Myc protein levels and phosphorylation of ERK1/2 by MEK1/2. Nemorosone also inhibits growth of Capan-1, AsPC-1, and MIA-PaCa-2 pancreatic cancer cells (IC50s = 4.5-5.0 μM following a 72-hour treatment) but not human dermal and foreskin fibroblasts (IC50s = >35 μM).1 It induces apoptosis, abolishes the mitochondrial membrane potential, and increases cytosolic calcium concentration in pancreatic cancer cells in a dose-dependent manner. Nemorosone activates the caspase cascade in a dose-dependent manner and inhibits cell cycle progression, increasing the proportion of cells in the G0/G1 phase, in both neuroblastoma and pancreatic cancer cells.1,2 Nemorosone (50 mg/kg, i.p., per day) also reduces tumor growth in an MIA-PaCa-2 mouse xenograft model.3References1. Holtrup, F., Bauer, A., Fellenberg, K., et al. Microarray analysis of nemorosone-induced cytotoxic effects on pancreatic cancer cells reveals activation of the unfolded protein response (UPR). Br. J. Pharmacol. 162(5), 1045-1059 (2011).2. Díaz-Carballo, D., Malak, S., Bardenheuer, W., et al. Cytotoxic activity of nemorosone in neuroblastoma cells. J. Cell. Mol. Med. 12(6B), 2598-2608 (2008).3. Wold, R.J., Hilger, R.A., Hoheisel, J.D., et al. In vivo activity and pharmacokinetics of nemorosone on pancreatic cancer xenografts. PLoS One 8(9), e74555 (2013). Nemorosone is a polycyclic polyprenylated acylphloroglucinol (PPAP) originally isolated from C. rosea that has antiproliferative properties.1 Nemorosone inhibits growth of NB69, Kelly, SK-N-AS, and LAN-1 neuroblastoma cells (IC50s = 3.1-6.3 μM), including several drug-resistant clones, but not MRC-5 human embryonic fibroblasts (IC50 = >40 μM).2 It increases DNA fragmentation in LAN-1 cells in a dose-dependent manner, and decreases N-Myc protein levels and phosphorylation of ERK1/2 by MEK1/2. Nemorosone also inhibits growth of Capan-1, AsPC-1, and MIA-PaCa-2 pancreatic cancer cells (IC50s = 4.5-5.0 μM following a 72-hour treatment) but not human dermal and foreskin fibroblasts (IC50s = >35 μM).1 It induces apoptosis, abolishes the mitochondrial membrane potential, and increases cytosolic calcium concentration in pancreatic cancer cells in a dose-dependent manner. Nemorosone activates the caspase cascade in a dose-dependent manner and inhibits cell cycle progression, increasing the proportion of cells in the G0/G1 phase, in both neuroblastoma and pancreatic cancer cells.1,2 Nemorosone (50 mg/kg, i.p., per day) also reduces tumor growth in an MIA-PaCa-2 mouse xenograft model.3 References1. Holtrup, F., Bauer, A., Fellenberg, K., et al. Microarray analysis of nemorosone-induced cytotoxic effects on pancreatic cancer cells reveals activation of the unfolded protein response (UPR). Br. J. Pharmacol. 162(5), 1045-1059 (2011).2. Díaz-Carballo, D., Malak, S., Bardenheuer, W., et al. Cytotoxic activity of nemorosone in neuroblastoma cells. J. Cell. Mol. Med. 12(6B), 2598-2608 (2008).3. Wold, R.J., Hilger, R.A., Hoheisel, J.D., et al. In vivo activity and pharmacokinetics of nemorosone on pancreatic cancer xenografts. PLoS One 8(9), e74555 (2013).

Mycothiazole is an inhibitor of mitochondrial electron transport chain (ETC) complex I. It exhibits cytotoxicity in cancer cells Huh7 (IC50 of 55.8 μM), U87, and MCF7. In Huh7 cells, Mycothiazole induces apoptosis (apoptosis). Additionally, Mycothiazole extends the lifespan of C. elegans by modulating transcription factors ATFS-1 and HSF1, which are associated with the unfolded protein response (UPR) and heat shock response (HSR).