DMH1 is a potent and selective inhibitor of BMP signaling. DMH1 is a direct inhibitor of ALK2 BMP type-I receptor ALK2 (activin receptor like kinase-2). DMH1 potently inhibits neoplastic phenotype in cancer cells.

Levistolide A is a naturally occurring compound isolated from Ligusticum chuanxiong Hort, which is used in traditional Chinese medicine to treat cancer. Levistolide has been studied in vitro against cell models for colon cancer and breast cancer. It was effective at inducing ER programmed apoptosis in colon cancer cells. In a cell model for breast cancer, levistolide was shown to enhance the apoptotic effects of adriamycin and vincristine. The effect of levistomide is correlated with cleavage of poly(ADP-ribose) polymerase PARP and up-regulation of caspase-3.

Schisandrin is a bioactive compound found in Schisandra chinensis. Schisandrin exhibits antioxidant properties and ameliorates ovariectomy-induced memory impairment in rats, and Aβ1-42-induced memory impairment in mice. Schisandrin has an anti-asthmatic effect on OVA-induced airway inflammation in a murine asthma model. The compound inhibits proliferation of breast cancer cell lines at concentrations of 20-100 uM.

U-104 is an inhibitor of CA IX that binds only to CA IX under hypoxic conditions in vivo. The binding results in significant inhibition of tumor growth and metastasis formation in both spontaneous and experimental models of metastasis. U-104 reduces the medium acidity by inhibiting the catalytic activity of the CA IX. It binds specifically only to hypoxic cells expressing CA IX.

Grindelic acid is a labdane-type diterpene that was reported as the main secondary metabolite from Grindelia chiloensis Cabr and G. pulchella Dunal var. pulchella (Asteraceae). Recent studies demonstrated potential pharmaceutical applications for grindelic acid and its synthetic derivatives. Grindelic acid is a NOX4 inhibitor (IC50 2 uM). Grindelic acid’s mechanism of action is unknown, but it inhibited neither ROS in a cell-free membrane-based NOX4 assay nor from the purified NOX4 dehydrogenase domain. Grindelic acid demonstrates in vitro antitumor activity against human breast, cervix, lung,colon cancer.

Arenobufagin, a representative natural bufadienolide compound, is the major active component extracted from toad venom. Arenobufagin is a part of Chinese medicine Chan'su. It possesses significant antineoplastic activity in vitro. Antineoplastic activity of arenobufagin was tested using cell lines from different cancers: breast cancer, hepatocellular carcinoma, prostatic cancer, etc. Arenobufagin acts by intercalating with DNA and disrupting the cell cycle. Also it was shown to inhibit PI3K/Akt/mTOR pathway (in hepatocellular carcinoma cells) and inhibit Na, K-ATPase.

Mertansine (Maytansine) is a 19–member ansa macrolide structure attached to a chlorinated benzenering. It was originally isolated from the shrub Maytenus ovatus. Mertansine (DM1) is a tubulin inhibitor, it inhibits the assembly of microtubules by binding to tubulin, with a linker structure can create an antibody-drug conjugate (ADC). Mertansine is a potent microtubule-targeted compound that induces mitotic arrest and kills tumor cells at sub-nanomolar concentrations. The antimitotic effect of maytansine has been attributed to its ability to inhibit microtubule assembly by binding to tubulin with a KD of ~ 1 umol/L, at or near the vinblastine-binding site. Experimental ADCs with the SPP-DM1 design include lorvotuzumab mertansine. DM1 can also be linked to an antibody using the SMCC (4-(3-mercapto-2,5-dioxo-1-pyrrolidinylmethyl)-cylohexanecarboxylic acid) linker, in which case the International Nonproprietary Name of the conjugate formed contains the word emtansine. DM1 and its attachment via these linkers result from ImmunoGen Inc research. Trastuzumab emtansine (T-DM1) is an anti-HER2/neu antibody-drug conjugate.

RKI 1447 is a potent and selective ROCK inhibitor. It displays anti-invasive and antitumor activities in breast cancer cells. RKI-1447 can inhibit the proliferation, migration and invasion abilities of ovarian cancer cells. RKI 1447 exhibits cytotoxic and cytostatic effects on VHL-deficient clear cell renal cell carcinoma (CC-RCC), making them candidate novel therapeutics for CC-RCC. RKI-1447 significantly inhibited mammary tumor growth in animal models.

BI-D1870 is a small molecule, which inhibits RSK1, RSK2, RSK3 and RSK4 in vitro with an IC(50) of 10-30 nM, but does not significantly inhibit ten other AGC kinase members and over 40 other protein kinases tested at 100-fold higher concentrations. BI-D1870 is cell permeant and prevents the RSK-mediated phorbol ester- and EGF (epidermal growth factor)-induced phosphorylation of glycogen synthase kinase-3beta and LKB1 in human embryonic kidney 293 cells and Rat-2 cells. BI-D1870 exhibited a dose-responsive antiproliferative effect on OSCC cells with relative sparing of normal human oral keratinocytes. The compound inhibited the downstream RSK target YB-1 and caused apoptosis. In addition, BI-D1870 also induced G2/M arrest by modulating the expression of p21 and other cell cycle regulators. BI-D1870 may be of useful in oral squamous cell carcinoma therapy. BI-D1870 has being shown to ameliorate experimental autoimmune encephalomyelitis in mice. BI-D1870 administration protected mice from EAE by reducing the infiltration of TH1 and TH17 cells into the CNS and decreasing mRNA levels of Ccr6 in TH17 cells. These results suggest that RSK inhibition is a promising strategy for the treatment of MS.

Astragaloside III is a naturally occurring triterpene saponin compound isolated from Radix Astragali, which has been demonstrated to have anti-gastric ulcer, immunomodulatory and antitumor effects.