Phytometabolites from coral jasmine flower extracts: Toxic effects on Spodoptera litura and enzyme inhibition in nontarget earthworm Eisenia fetida as an alternative approach

Green pesticides, derived from natural sources, have gained wider attention as an alternative to synthetic pesticides for managing polyphagous pests, such as Spodoptera litura. In this study, the methanolic flower extract of Nyctanthes arbor-tristis (Mx-Na-t) was subjected to chemical screening, and 3-hydroxy-1,2-dimethyl-4(1H)-pyridone (3H-dp) and tyrosol (Ty-ol) were identified as the major derivatives. The toxic effects of Mx-Na-t (500 ppm) were highest in third-instar S. litura larvae (96.4%), while those of 3H-dp and Ty-ol (5 ppm) were highest in second-instar larvae (76.5% and 81.4%, respectively). The growth and development of S. litura larvae and pupae were significantly reduced by all three treatments. Fecundity rates were also reduced by all treatments [from 1020 eggs (control) to 540 eggs by Mx-Na-t treatment, 741 eggs by 3H-dp treatment, and 721 eggs by Ty-ol treatment]. The extract and its active constituents decreased adult emergence and slowed total larval development in a dose-dependent manner. A decrease was noted in the major gut enzymes of young S. litura larvae exposed to Mx-Na-t, 3H-dp, and Ty-ol. Moreover, midgut tissues of fourth-instar larvae were severely damaged by Mx-Na-t (250 ppm), 3H-dp (2.5 ppm), and Ty-ol (2.5 ppm); the treatments induced structural damage to the epithelial cells and gut lumen. The earthworm Eisenia fetida was used to assess nontarget toxicity. Compared with cypermethrin, the phytochemicals exhibited minimal effects on the earthworm's detoxifying enzymes superoxide dismutase and catalase after 14 days of treatment. Moreover, in silico predictions using BeeTox and ProTox-II indicated little or no toxicity of 3H-dp and Ty-ol toward honey bees and other nontarget species.

Bioefficacy of Epaltes divaricata (L.) n-Hexane Extracts and Their Major Metabolites against the Lepidopteran Pests Spodoptera litura (fab.) and Dengue Mosquito Aedes aegypti (Linn.)

The present research investigated the chemical characterization and insecticidal activity of n-Hexane extracts of Epaltes divaricata (NH-EDx) along with their chief derivatives n-Hexadecanoic acid (n-HDa) and n-Octadecanoic acid (n-ODa) against the dengue vector Aedes aegypti and lepidopteran pest Spodoptera litura. Chemical screening of NH-EDx through GC-MS analysis delivered nine major derivatives, and the maximum peak area percentage was observed in n-Hexadecanoic acid (14.63%) followed by n-Octadecadienoic acid (6.73%). The larvicidal activity of NH-EDx (1000 ppm), n-HDa (5 ppm), and n-ODa (5 ppm) against the A. aegypti and S. litura larvae showed significant mortality rate in a dose-dependent way across all the instars. The larvicidal activity was profound in the A. aegypti as compared to the S. litura across all the larval instars. The sublethal dosages of NH-EDx (500 ppm), n-HDa (2.5 ppm), and n-ODa (2.5 ppm) also showed alterations in the larval/pupal durations and adult longevity in both the insect pests. The enzyme activity revealed that the α- and β-carboxylesterase levels were decreased significantly in both the insect pests, whereas the levels of GST and CYP450 uplifted in a dose-dependent manner of NH-EDx, n-HDa, and n-ODa. Correspondingly, midgut tissues such as the epithelial layer (EL), gut lumen (GL), peritrophic matrix (Pm), and brush border membrane (BBM) were significantly altered in their morphology across both A. aegypti and S. litura against the NH-EDx and their bioactive metabolites. NH-EDx and their bioactive metabolites n-HDa and n-ODa showed significant larvicidal, growth retardant, enzyme inhibition, and midgut toxicity effects against two crucial agriculturally and medically challenging insect pest of ecological importance.

Antitumor activity of NRC-AN-019 in a pre-clinical breast cancer model

Breast cancer is the second most frequently diagnosed tumor in women. Overexpression of human epidermal growth factor receptors (EGFRs) represents a biological subclass of breast cancer with distinct molecular alterations, clinical behavior and response to systemic therapy. In this study, we describe a novel compound (NRC-AN-019), which has better antitumor activity than Lapatinib. Here, we demonstrate that NRC-AN-019 is more effective in inhibiting angiogenic potential and proliferation of both MDAMB231 and HTB20/BT474 cells. FACS analysis shows that NRC-AN-019 treatment caused the accumulation of MDAMB231 and BT474 cells in the sub G0/1 phase in a dose-dependent manner and was accompanied by increased PARP cleavage, which is indicative of apoptosis. In addition, we observed inhibition of EGFR phosphorylation in both MDAMB231 and BT474 cells. From our animal studies using SCID mice implanted with BT474 cells, we observed dose-dependent inhibition of tumor growth in NRC-AN-019-treated animals compared to controls or Lapatinib-treated mice at comparable concentrations. The dose-dependent inhibition of EGFR phosphorylation was confirmed by immunohistochemical analysis of tumor sections. In vitro results demonstrate that NRC-AN-019 is superior to Lapatinib in EGFR-overexpressing cells and has strong anti-angiogenic, anti-proliferative and pro-apoptotic properties in an EGFR-overexpressing background (BT474). In vivo studies demonstrate that the antitumor activity of NRC-AN-019 is better over Lapatinib. These results suggest that NRC-AN-019 has greater therapeutic potential in the treatment of Her-2-positive breast cancer.

Abstract 5369: AN019 in combination with ionizing radiation retards intracranial tumor growth and inhibits angiogenic induction in vitro and in vivo

Successful treatment of malignant glioma is hampered by the development of resistance to alkylating agents such as Temozolomide (TMZ). The addition of radiation to a TMZ treatment regime has shown promising results with reported survivability of up to 5 years. One of the side effects of Temozolomide is the increased activation of angiogenic factors which may work contrary to the desired result. In this report we demonstrate the development of a novel compound AN019, showing specific VEGF suppression accompanied with anti-angiogenic and anti-proliferative properties in gliomas. We used U87, a glioma cell line, and EGFRvIII over-expressing glioma xenograft 4910 cells for this study. Deduced IC50 values indicated that AN019 had greater anti-proliferative effect than Temozolomide (U87: AN019=103µM, TMZ=768µM; 4910: AN019=169µM, TMZ=582µM). Matrigel invasion assay indicated that AN019 retarded the invasive potential of both U87 and 4910 glioma cells over TMZ treated cells which was enhanced after radiation treatment. In-vitro angiogenic and migration assays showed an almost complete inhibition of angiogenic induction and migration in U87 and 4910 cells after AN019 treatment when compared to TMZ. Cell cycle analysis revealed that 100µg/ml concentration of AN019 was sufficient to achieve >70% apoptosis in both U87 and 4910 cells, whereas 150µg/ml of TMZ was required to achieve the same response. Western blot and ELISA for the expression of VEGF levels indicated that lower concentrations of AN019 (U87=86±3µg/ml and 12±1µg/ml with radiation; 4910=100±1µg/ml and 6µg/ml with radiation) were required for 50% inhibition of VEGF expression. TMZ treatment required a higher concentration to achieve similar 50% inhibition of VEGF expression (U87=80±10µg/ml and 12±3µg/ml with radiation; 4910=100±3µg/ml and 27±3µg/ml with radiation). Animal studies showed that oral doses of AN019 (20mg/kg) regressed tumors in all animals and 70% of the animals showed complete absence of intracranial tumors, whereas TMZ (100mg/kg) treated animals also showed regression of tumors with a 30% cure rate. Overall, our results demonstrate that AN019 has anti-angiogenic, anti-proliferative and anti-tumorogenic properties which may have clinical implications.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 5369.

Abstract 3631: AN019, a potent anticancer agent, suppresses tumors, ErbB-2, and angiogenesis in pancreatic cancer cells

Epidermal growth factor receptor (EGFR), a member of the HER family of receptor tyrosine kinases, has been identified as a therapeutic target for pancreatic cancer. Excessive ErbB-2 signaling is associated with the development of a wide variety of solid malignancies. In this study, we used the pancreatic cancer cell lines MIA PaCa-2 and PANC-1 to demonstrate the suppressive, anti-angiogenic, and anti-proliferative effects of a novel compound known as AN019. Here, we show that AN019 inhibits the invasiveness of pancreatic cancer cells in a dose-dependent manner and is superior to treatment with Gemcitabine alone. Angiogenic assays demonstrated that AN019 treatment retarded the invasive potential of pancreatic cancer cells and provided greater angiogenic inhibition than Gemcitabine. In addition, western blot analysis demonstrated that AN019 inhibits expression of ErbB-2 in a dose-dependent manner in MIA PaCa-2 and PANC-1 cells. In contrast, Gemcitabine lacked a similar dose response. Finally, the proliferation assay showed that while AN019 retarded proliferation in a dose-dependent manner, Gemcitabine did not. Our in vivo studies showed that expression of ErbB-2 and VEGF decreased in a dose-dependent manner in AN019-treated animals with subcutaneously implanted MIA PaCa-2 tumors. A treatment combination of AN019 and Gemcitabine had an effect similar to that of treatment with AN019 alone, thereby indicating no specific contribution from Gemcitabine. Our results demonstrate AN019 is superior to Gemcitabine, and AN019 is a specific suppressor of ErBB-2 in vitro and in vivo. In addition, AN019 has anti-proliferative and anti-angiogenic properties. Taken together, these results clearly indicate the potential therapeutic use of AN019 as an anti-cancer agent.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 3631.

Abstract 3635: Novel chemotherapeutic agent AN019 for lapatinib-resistant breast cancer

Breast cancer is the most frequently diagnosed cancer in women. Overexpression of human epidermal growth factor receptors (EGFRs) represents a biological subclass of breast cancer with distinct molecular alterations, clinical behavior, and response to systemic therapy. In this study, we introduce a novel compound (AN019) that has greater anti-tumor activity than Lapatinib. We demonstrate that AN019 is more effective at inhibiting the angiogenic potential and proliferation of both MDAMB231 and HTB20/BT474 cells. FACS analysis shows that AN019 treatment also caused the accumulation of MDAMB231 and HTB20/BT474 cells in the sub-G0/1 phase in a dose-dependent manner; this effect was accompanied by increased PARP cleavage indicative of apoptosis. Strong inhibition of EGFR phosphorylation was also observed in both MDAMB231 and HTB20/BT474 cells. HTB20/BT474 cells did not respond well to Lapatinib treatment when compared to AN019 treatment. From our animal studies using SCID mice implanted with HTB20/BT474 cells, we observed a dose-dependent inhibition of tumor growth when compared to controls or Lapatinib-treated mice at comparable concentrations. A dose-dependent inhibition of EGFR phosphorylation was also observed from immunohistochemical analysis of tumor sections. Our results show that AN019 is superior to Lapatinib in EGFR-overexpressing cells and has strong anti-angiogenic, anti-proliferative and pro-apoptotic properties. In vivo studies demonstrate the increased anti-tumor activity of AN019 over Lapatinib. These results suggest the therapeutic potential of AN019 as anti-angiogenic and anti-proliferative agent in Lapatinib-resistant and EGFR-overexpressing cells.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 3635.