Targeting ADAM-mediated ligand cleavage to inhibit HER3 and EGFR pathways in non-small cell lung cancer.

We describe here the existence of a heregulin-HER3 autocrine loop, and the contribution of heregulin-dependent, HER2-mediated HER3 activation to gefitinib insensitivity in non-small cell lung cancer (NSCLC). ADAM17 protein, a major ErbB ligand sheddase, is upregulated in NSCLC and is required not only for heregulin-dependent HER3 signaling, but also for EGFR ligand-dependent signaling in NSCLC cell lines. A selective ADAM inhibitor, INCB3619, prevents the processing and activation of multiple ErbB ligands, including heregulin. In addition, INCB3619 inhibits gefitinib-resistant HER3 signaling and enhances gefitinib inhibition of EGFR signaling in NSCLC. These results show that ADAM inhibition affects multiple ErbB pathways in NSCLC and thus offers an excellent opportunity for pharmacological intervention, either alone or in combination with other drugs.

Effect of pre-treatments and frying conditions on the formation of starch-lipid complex in potato starch chips during deep-frying process.

This study examined the influence of various pretreatment methods, frying durations, and temperatures, as well as the type of frying oil, on the formation and structure of starch-lipid complexes in fried potato chips. Potato starch was processed into dough, sliced, and subjected to deep frying following various pretreatments. Structural analysis showed that steaming as a pretreatment facilitated the generation of V-type starch-lipid complexes, whereas resistant starch type III (RS3) materialized in the desiccated samples instead of the anticipated complexes. The rate of starch-lipid complex formation initially surged but subsequently declined as treatment time increased. A reduction in treatment temperature from 190 °C to 170 °C was conducive to complex formation. Moreover, the maximum relative crystallinity (19.74 %) and ΔH value (7.76 J/g) were recorded for potato starch slices pretreated by steaming and frying in palm oil. Rapeseed oil, which is rich in unsaturated fatty acids (89.98 %), inhibits complex formation. The study concludes that pretreatment methods exert a substantial effect on the formation of starch-lipid complexes and that extended frying duration and elevated temperature may reduce this formation. Oils with longer-chain fatty acids and a lower degree of unsaturation were favorable for complex formation.

Variations in Mating and Reproduction in Oriental Fruit Moth Caused by Adult Physiological State in Laboratory Tests.

Grapholita molesta (Busck) is a pest of rosaceous fruit plants worldwide. Due to a combination of monandry and promiscuity in G. molesta, the age and mating history of both sexes significantly affected the mating and reproductive success. In this study, the interactions of different ages (3, 5, or 7 days) and mating history (unmated or mated) in each sex on the mating selection, reproductive system, and offspring production were investigated in the laboratory. The results showed that these differences mainly occurred in young females or males, associated with unmated or mated state. Especially, the 3-day-old unmated females were preferred by the 7-day-old males but discriminated against by the 3- or 5-day-old unmated males, whereas the 3-day-old mated males were preferred by the 3-day-old mated or 7-day-old females but discriminated against by the 3- or 5-day-old unmated females. The lengths of the ovarian ducts were affected by age in the unmated females, with the greatest length being found at 7 days old. The size of testes varied with age in the unmated males, being the largest at 3 days old. At 3 days old, the testes size of the unmated males was larger than that of the mated males. The pairing of 5-day-old unmated females × 3-day-old mated males maximized the successful matings. The least productive pairing was 7-day-old unmated females × 5-day-old mated males. The pairing of 5-day-old mated males × 3-day-old mated females had the lowest number of matings and the highest number of offspring. The pairing of 3-day-old mated females × 3-day-old mated males had a high rate of mating success and the most offspring. These results revealed the different roles between females and males because of physiological states in terms of the reproductive biology in G. molesta.

Discovery of a potent, selective, and orally active human epidermal growth factor receptor-2 sheddase inhibitor for the treatment of cancer.

The design, synthesis, evaluation, and identification of a novel class of (6S,7S)-N-hydroxy-6-carboxamide-5-azaspiro[2.5]octane-7-carboxamides as the first potent and selective inhibitors of human epidermal growth factor receptor-2 (HER-2) sheddase is described. Several compounds were identified that possess excellent pharmacodynamic and pharmacokinetic properties and were shown to decrease tumor size, cleaved HER-2 extracellular domain plasma levels, and potentiate the effects of the humanized anti-HER-2 monoclonal antibody (trastuzumab) in vivo in a HER-2 overexpressing cancer murine xenograft model.

Selective inhibition of ADAM metalloproteases blocks HER-2 extracellular domain (ECD) cleavage and potentiates the anti-tumor effects of trastuzumab.

The HER-2 receptor tyrosine kinase is an important regulator of cell proliferation and survival, and it is a clinically validated target of therapeutic intervention for HER-2 positive breast cancer patients. Its extracellular domain (ECD) is frequently cleaved by protease(s) in HER-2 overexpressing breast cancer patients, rendering the remaining membrane-bound portion (p95) a constitutively activated kinase. The presence of both serum ECD and cellular p95 protein has been linked to poor clinical outcome as well as reduced effectiveness of some therapeutic treatments. We have identified a series of potent, selective small molecule inhibitors of ADAM proteases, exemplified here by INCB003619, and demonstrate that these inhibitors effectively block HER-2 cleavage in HER-2 overexpressing human breast cancer cell lines. Intriguingly, when used in combination, INCB003619 dramatically enhances the antiproliferative activity of suboptimal doses of the anti-HER-2 antibody, trastuzumab, in HER-2 overexpressing/shedding breast cancer cell lines, accompanied by reduced ERK and AKT phosphorylation. Furthermore, INCB003619, in combination with trastuzumab, augments the pro-apoptotic and antiproliferative effects of the chemotherapeutic agent paclitaxel. Consistent with these in vitro data, INCB003619 reduces serum ECD levels and enhances the antitumor effect of trastuzumab in a xenograft tumor model derived from the HER-2 overexpressing BT-474 breast cancer cell line. Collectively, these findings suggest that blocking HER-2 cleavage with selective ADAM inhibitors may represent a novel therapeutic approach for treating HER-2 overexpressing breast cancer patients.

Efficacy and safety of FdUMP[10] in treatment of HT-29 human colon cancer xenografts.

Thymidylate synthase (TS) is the molecular target of fluoropyrimidine (FP) chemotherapy, and novel anticancer drugs effective against TS-overexpressing tumors are required to treat patients with FP-refractory solid tumors. We have evaluated the inhibition of cell proliferation in vitro and antitumor activity in vivo of FdUMP[10], an oligodeoxynucleotide 10mer in which 5-fluorouracil (5-FU) is the only nucleobase. FdUMP[10] is a pro-drug of FdUMP, the TS inhibitory metabolite of FPs. FdUMP[10] was 338-fold more potent than 5-FU at inhibiting cell proliferation in the NCI 60 cell line screen. The antitumor activity of FdUMP[10] was compared to 5-FU using H-T29 xenografts in female CD-1 athymic (nu+/nu+) mice. Treatment with FdUMP[10] as a single agent (40 mg/kg/daily x 5, i.v.) delayed tumor growth and resulted in a smaller mean tumor size (T/C value = 51%, p<0.001 compared with the control group). Treatment with 5-FU (25 mg/kg/daily x 5, i.p.) had similar results as single agent FdUMP[10] (T/C value = 65%, p=0.238 compared with the FdUMP[10] treated group. Simultaneous treatment of tumor-bearing mice with both drugs (FdUMP[10] plus 5-FU) further delayed tumor growth (T/C value = 36%; p=0.003 relative to 5-FU). The results from the combined treatment group were not, however, statistically significant relative to the group receiving single agent FdUMP[10] treatment (p=0.059). Histological examination revealed systemic damage was limited to the colonic epithelium in all treatment groups and was least extensive with single agent FdUMP[10] compared to the other treatment groups. The data support the concept that FdUMP[10] is a useful prototype of a novel type of FP that is likely to be more efficacious than FPs in clinical use.

Discovery of potent competitive inhibitors of indoleamine 2,3-dioxygenase with in vivo pharmacodynamic activity and efficacy in a mouse melanoma model.

A hydroxyamidine chemotype has been discovered as a key pharmacophore in novel inhibitors of indoleamine 2,3-dioxygenase (IDO). Optimization led to the identification of 5l, which is a potent (HeLa IC(50) = 19 nM) competitive inhibitor of IDO. Testing of 5l in mice demonstrated pharmacodynamic inhibition of IDO, as measured by decreased kynurenine levels (>50%) in plasma and dose dependent efficacy in mice bearing GM-CSF-secreting B16 melanoma tumors.