Vaccenic acid (VA) (t11 octadecenoic acid) is a positional and geometric isomer of oleic acid (c9-octadecenoic acid), and is the predominant trans monoene in ruminant fats (50%–80% of total trans content). Dietary VA can be desaturated to cis-9,trans-11 conjugated linoleic acid (c9,t11-CLA) in ruminants, rodents, and humans. Hydrogenated plant oils are another source of VA in the diet, and it has been recently estimated that this source may contribute to about 13%–17% of total VA intake. In contrast to suggestions from the epidemiological studies, the majority of studies using cancer cell lines (Awad et al. 1995; Miller et al. 2003) or rodent tumors (Banni et al. 2001; Corl et al. 2003; Ip et al. 1999; Sauer et al. 2004) have demonstrated that VA reduces cell growth and (or) tumor metabolism. Animal and in vitro studies suggest that the anti-cancer properties of VA are due, in part, to the in vivo conversion of VA to c9,t11-CLA. However, several additional mechanisms for the anti-cancer effects of VA have been proposed, including changes in phosphatidylinositol hydrolysis, reduced proliferation, increased apoptosis, and inhibition of fatty acid uptake. In conclusion, although the epidemiological evidence of VA intake and cancer risk suggests a positive relationship, this is not supported by the few animal studies that have been performed. The majority of the studies suggest that any health benefit of VA may be conferred by in vivo mammalian conversion of VA to c9,t11-CLA. VA acts as a partial agonist to both peroxisome proliferator-activated receptors (PPAR)-α and PPAR-γ in vitro, with similar affinity compared to commonly known PPAR agonists. Hypolipidemic and antihypertrophic bioactivity of VA is potentially mediated via PPAR-/-dependent pathways.

FGF-401 is an inhibitor of human fibroblast growth factor receptor 4 (FGFR4), with potential antineoplastic activity. Upon administration, FGF401 binds to and inhibits the activity of FGFR4, which leads to an inhibition of tumor cell proliferation in FGFR4-overexpressing cells. FGFR4 is a receptor tyrosine kinase upregulated in certain tumor cells and involved in tumor cell proliferation, differentiation, angiogenesis, and survival. FGF-401 is an FGFR4 inhibitor in phase I/II clinical studies at Novartis for the treatment of positive FGFR4 and KLB expression solid tumors and hepatocellular carcinoma.

CX-5461 represents an innovative-targeted agent with numerous differentiating features when compared to current options for treatment of hematologic cancers. CX-5461 is a first-in-class small molecule inhibitor of RNA polymerase I (Pol I) that triggers the nucleolar stress surveillance pathways to activate p53, without causing direct DNA damage. Molecular studies demonstrate that CX-5461 inhibits the initiation stage of rRNA synthesis and induces both senescence and autophagy, but not apoptosis, through a p53-independent process in solid tumor cell lines. Currently, CX-5461 is in clinical trial for patients with advanced hematological malignancies.

PLX8394 is a potent and selective inhibitor of B-Raf V600E (IC50 14 nM for WT and 3.8 nM for V600E mutant). Unlike vermurafenib, sorafenib and dabrafenib, PLX8394 does not cause paradoxical MAPK pathway activation. PLX8394 is under investigation in phase I/II of clinical trial for the treatment patients with advanced unresectable solid tumors.

SN38 (7-ethyl-10-hydroxy camptothecin) is a prominent and efficacious anticancer agent. It is poorly soluble in both water and pharmaceutically approved solvents; therefore, the direct formulation of SN38 in solution form is limited. SN38 is formed via hydrolysis of irinotecan by carboxylesterases and metabolized via glucuronidation by UGT1A1. Currently, the water soluble prodrug of SN38, irinotecan (CPT-11), is formulated as a low pH solution and is approved for chemotherapy. SN38 causes the strongest inhibition of DNA topoisomerase I, followed by CPT and then CPT-11. CPT-11 dose dependently shifts the position of relaxed DNA in the direction of nicked DNA, but SN38 and CPT shows no effect on the position of relaxed DNA. SN38 dose-dependently and time-dependently inhibit DNA synthesis. Respective IC50 values of SN38, in DNA synthesis is 0.077 uM.

Elacridar is an oral bioenhancer that targets multiple drug resistance in tumors. Elacridar is a strong and relatively specific inhibitor of P-gp and BCRP, two main efflux transporters. Development of elacridar is assumed to have been discontinued.

JNJ-38877605 is an orally available, small molecule inhibitor of the proto-oncogene c-Met (hepatocyte growth factor receptor [HGFR]) with potential antineoplastic activity. c-Met inhibitor JNJ-38877605 selectively binds to c-Met, thereby inhibiting c-Met phosphorylation and disrupting c-Met signal transduction pathways. JNJ-38877605 was in Phase I clinical trials. Combined clinical and correlative preclinical studies suggest that renal toxicity of JNJ-38877605 is caused by the formation of species-specific insoluble metabolites. These observations preclude further clinical development of JNJ-38877605.

SB-203580 was originally prepared as inflammatory cytokine synthesis inhibitor that subsequently was found to be selective inhibitor of p38 MAP kinase. SB-203580 is a p38 MAPK inhibitor with IC50 of 0.3-0.5 uM in THP-1 cells, 10-fold less sensitive to SAPK3(106T) and SAPK4(106T) and blocks PKB phosphorylation with IC50 of 3-5 uM. SB203580 induces autophagy in human hepatocellular carcinoma (HCC) cells. Development of SB-203580 for cancer; postmenopausal osteoporosis; rheumatoid arthritis; septic shock has been discontinued.

Carnosol is an ortho-diphenolic diterpene with an abietane carbon skeleton with hydroxyl groups at positions C-11 and C-12 and a lactone moiety across the B ring. Carnosol is the product of oxidative degradation of carnosic acid. Carnosol is a naturally occurring phytopolyphenol found in rosemary that functions as an antioxidant, antimicrobial, and anticarcinogen. Carnosol has been shown to inhibit inductions of COX-2 by blocking PKC signaling. Carnosol is an inhibitor of AR and ER α. Several pre-clinical studies have suggested that carnosol selectively targets tumorigenic cell as opposed to non-tumorigenic cells and is safe and tolerable in animals. Carnosol has been shown to elicit chemopreventive effects by (1) blocking the bioactivation of carcinogens, (2) enhancing antioxidant and/or detoxification enzyme activities, (3) suppressing tumor-promoting inflammation, (4) inhibiting cell proliferation and inducing apoptosis selectively in cancer cells, and (5) blocking tumor angiogenesis and invasion.

SAR-405838 is an inhibitor of the interaction between the oncoprotein murine double minute 2 (MDM2) and p53. SAR-405838 was investigated in phase I clinical trials in patients with locally advanced/metastatic solid tumor with wild-type TP53 or with TP53 mutation prevalence below 40%. SAR-405838 had an acceptable safety profile with limited activity in patients with advanced solid tumors.