pp2b

Voclosporin (ISAtx-247) 是一种新型且可口服钙调磷酸酶(CN; PP2B)抑制剂和免疫抑制剂，可用于治疗狼疮性肾炎。

Fenvalerate (Evercide 2362) 是一种蛋白磷酸酶 2B (calcineurin) 抑制剂，是合成拟除虫菊酯杀虫剂，抑制 PP2B-Aα。高剂量 Fenvalerate 会损害认知和行为发育。Fenvalerate 通过 Fas FasL 信号通路诱导小鼠睾丸中的生殖细胞凋亡。

Okadaic acid 是一种强效的聚醚海洋毒素，在海洋软体动物的消化腺中积聚。Okadaic acid 是一种具有高效性和选择性的蛋白质磷酸酶 (PP) 抑制剂，抑制 PP1、PP2A 、PP3 、PP4 和 PP5 。Okadaic acid 激活人 HepaRG 细胞中的 Wnt β-catenin 信号传导。

Okadaic acid ammonium salt, a marine toxin, serves as an inhibitor of protein phosphatases (PP), displaying a higher affinity for PP2A (IC 50 =0.1-0.3 nM) alongside inhibitory effects on PP1 (IC 50 =15-50 nM), PP3 (IC 50 =3.7-4 nM), PP4 (IC 50 =0.1 nM), and PP5 (IC 50 =3.5 nM), but does not affect PP2C. By inhibiting PPs, this compound promotes protein phosphorylation and acts as a tumor promoter. Additionally, it is involved in inducing tau phosphorylation.

Cytostatin (sodium salt) is a natural antitumor inhibitor of cell adhesion to extracellular matrix, blocking adhesion of B16 melanoma cells to laminin and collagen type IV in vitro (IC50s = 1.3 and 1.4 μg/ml, respectively) and B16 cells metastatic activity in mice. It induces apoptosis of FS3 mouse fibrosarcoma cells (IC50 = 3.1 μg/ml). Cytostatin (sodium salt) potently and selectively inhibits protein phosphatase 2A (PP2A; IC50 = 29 nM against the catalytic subunit), while having no effect against PP1, PP2B, or PP5.

The cyanobacterium Nodularia spumigena often contaminates the drinking water of rural communities in developing countries and accumulates in mussels, flounder, and cod from the northern Baltic Sea. Nodularin is a hepatotoxic monocylic pentapeptide produced by the N. spumigena. It is a potent inhibitor of protein phosphatase types 1 (PP1) and 2A (PP2A), exhibiting IC50 values of 1.8 and 0.026 nM, respectively. PP2B is inhibited to a lesser extent with an IC50 of 1.8 μM. No apparent inhibitory effect is observed with PP2C, alkaline phosphatase, acid phosphatase, insulin receptor tyrosine kinase, protein kinase A, phosphorylase kinase, or protein kinase C.

Cytostatin is a natural antitumor inhibitor of cell adhesion to extracellular matrix, blocking adhesion of B16 melanoma cells to laminin and collagen type IV in vitro (IC50s = 1.3 and 1.4 μg ml, respectively) and B16 cells metastatic activity in mice. It induces apoptosis of FS3 mouse fibrosarcoma cells (IC50 = 3.1 μg ml). Cytostatin potently and selectively inhibits protein phosphatase 2A (PP2A; IC50 = 29 nM against the catalytic subunit), while having no effect against PP1, PP2B, or PP5.

Fostriecin (free base) is an inhibitor of the serine threonine protein phosphatases 2A (PP2A) and 4 (PP4) (IC50s = 3.2 and 3 nM, respectively). It less effectively inhibits topoisomerase II and PP1 (IC50s = 40 and 131 μM, respectively) and does not inhibit PP2B. Through its effects on protein phosphatases, fostriecin increases the level of histone H3 phosphorylation and may alter epigenetic regulation of cell proliferation. On a related note, fostriecin was first identified as an antitumor antibiotic.