bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 1216: Effects of phenformin in LKB1/KRAS mutated non-small cell lung cancer patient derived xenograft
Authors: Moro Massimo , Roz Luca , Caserini Roberto , Pastorino Ugo , Sozzi Gabriella
Published: May 2015

Metformin is an oral antidiabetic drug of the biguanide class. Several epidemiological and case-control studies reported that diabetics using metformin may have lower cancer risk in comparison to those using other antidiabetic medications. Recent studies in experimental models suggest that another biguanide, phenformin, has higher anticancer activity compared with metformin. The aim of this study was to evaluate the effects of metformin and phenformin in Non-Small Cell Lung Cancer (NSCLC) models. In particular, the effects of these compounds in LKB1 or LKB1/KRAS mutated compared to wild type models have been investigated. NSCLC cell lines (A549, H460, H1299, LT73) have been treated with either metformin or phenformin to evaluate in vitro dose/response depending on the different mutational status of KRAS and LKB1 genes. The effects of the two biguanide have been investigated also in vivo models, exploiting the panel of Patient Derived Xenografts (PDXs) directly generated from NSCLC patients in our Institute. In vitro experiments indicated that cell lines with already impaired metabolism (LKB1 and/or KRAS mutated) were more sensitive to phenformin treatment. Interestingly, treatments of these cell lines with r phenformin resulted in a 50% decrease in the amount of CD133+ Tumor Initiating Cells (TIC). Moreover, high doses of phenformin (LD75) did not result in the increase of TIC previously observed after Cisplatin treatment. In vivo, early treatments (Tumor Volume = 50-100mm3) of an LKB1 mutated PDX model resulted in a significant reduction of tumor volume (300 ± 50 mm3 in phenformin treated vs 750 ± 100 mm3 in vehicle treated tumors) already after three weeks of treatment (100mg/Kg/day). Importantly, no regrowth was observed in responding tumors even after the end of treatments. No effects were observed in LKB1 wild type PDX treated with phenformin. Taken together, these preliminary data indicate a selective action of phenformin on LKB1 mutated lung adenocarcinoma models in vitro and in vivo. Interestingly, this compound seems to be more active in TIC than normal chemotherapeutic drugs (i.e. cisplatin). Effects of biguanide on TIC could be the cause of the lack of tumor regrowth after treatment, thus making these compounds potentially useful in counteracting disease recurrence and/or metastasis formation. Further investigations are needed to elucidate the different effects of metformin and phenformin in double mutated (LKB1 and KRAS) PDXs models.

Citation Format: Massimo Moro, Luca Roz, Roberto Caserini, Ugo Pastorino, Gabriella Sozzi. Effects of phenformin in LKB1/KRAS mutated non-small cell lung cancer patient derived xenograft. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 1216. doi:10.1158/1538-7445.AM2014-1216
Abstract 1225: Generation and characterization of a sorafenib-resistant hepatocellular carcinoma model from patient-derived tumor xenografts
Authors: Hu Gang , Fang Houshan , Tang Xuzhen , Ouyang Kedong , Yang Xueyan , Xie Fubo , Wang Ke , Zhang Yixin , Jiang Zhenzhou , Zhang Luyong , Zhou He , Tao Weikang
Published: May 2015

Hepatocellular carcinoma (HCC) is a common malignancy worldwide and sorafenib is a standard of care therapeutics for unresectable HCC. Although sorafenib, a multikinase inhibitor, can suppress both angiogenesis and cell proliferation, its efficacy is hampered by the emergency of drug resistance during the treatment. Thus, it is useful to understand the mechanism underlying sorafenib resistance in an animal model with resemblance of human HCC. Here, we report the generation and characterization of a sorafenib-resistant HCC xenograft model derived from patient tumors. A patient-derived xenograft (PDX) mouse model (LIX004) was treated with sorafenib. While sorafenib inhibited tumor growth at the initial stage of treatment, a few tumors regrew after prolonged sorafenib treatment. A cancer cell line (LIXC-004SR) was generated from a resistant tumor and the xenograft derived from this cell line maintained sorafenib resistance in vivo. On contrary, another cell line (LIXC-004NA) established from the treatment-naïve LIX004 PDX model remained sensitive to sorafenib. We compared the gene expression profiles between these two cell lines using both cDNA microarray and qPCR and found that a class of genes involved in angiogenesis were significantly upregulated in LIXC-004SR cells vs. LIXC-004NA cells, which include those encoding secreted angiogenesis stimulators such as MMP1, FGF-5 and VEGFA. Consistently, increased angiogenesis was detected in sorafenib-resistant LIXC-004SR tumor compared to sorafenib-sensitive LIXC-004NA tumor. Furthermore, the conditional medium from LIXC-004SR cell culture could stimulate HUVEC proliferation as well as MEK,ERK and Akt phosphorylation. These results suggest that sorafenib resistance may arise by bypassing the inhibition of angiogenesis via upgregulation of pro-agiogenesis genes. The generation and molecular characterization of sorafenib-resistant tumor models could shed light on the mechanism of sorafenib resistance which may aid in the development of strategies to overcome drug resistance.

Citation Format: Gang Hu, Houshan Fang, Xuzhen Tang, Kedong Ouyang, Xueyan Yang, Fubo Xie, Ke Wang, Yixin Zhang, Zhenzhou Jiang, Luyong Zhang, He Zhou, Weikang Tao. Generation and characterization of a sorafenib-resistant hepatocellular carcinoma model from patient-derived tumor xenografts. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 1225. doi:10.1158/1538-7445.AM2014-1225
Abstract 1233: Inhibition of STAT-3 by piperlongumine induces anoikis, prevents tumor formation in pancreatic cancer in vitro and in vivo
Authors: Fofaria Neel Manoj , Srivastava Sanjay K.
Published: May 2015

Metastasis of pancreatic cancer is a major challenge leading to the failure of its therapy. Hence, novel strategies to prevent metastasis are of prime importance. Anoikis is an anchorage independent cell death. Resistance to anoikis is one of the key features of a metastatic cell. In the current study, we show induction of anoikis by piperlongumine, a component of black pepper, through inhibition of STAT-3. Treatment of various pancreatic cancer cell lines under low attachment conditions with piperlongumine reduced the anoikis resistance in a concentration-dependent manner. The decrease in anoikis resistance was associated with decrease in the expression of STAT-3 and its phosphorylation at Y705. Significant down-regulation of Bcl-2 and Mcl-1, which are under the transcriptional regulation of STAT-3, were also observed by piperlongumine treatment indicating the role of STAT-3 in anoikis. Concentration-dependent cleavage of poly (ADP-ribose) polymerase (PARP) was observed by piperlongumine treatment in these cells. IL-6 treatment not only increased the phophorylation of STAT-3 at Y05 but also abrogated the anoikis induced by piperlongumine in Panc-1 and HPAC cells. Silencing STAT-3 by shSTAT-3 sensitized BxPc-3 and Panc-1 cells to piperlongumine treatment. On the other hand, over-expression of STAT-3 in Panc-1 cells conferred resistance to anoikis induced by piperlongumine. STAT-3 -/- BxPc-3 cells were highly sensitive to anoikis upon piperlongumine treatment. Finally, our in vivo studies established that pancreatic cancer cells treated with piperlongumine in suspension condition lost their potential to form tumors in xenograft model. On the other hand, untreated cells in suspension conditions formed aggressive tumors. Moreover, cells treated with PL in suspension conditions completely failed to metastasize when injected intravenously in mice whereas the untreated cells extensively metastasized in lungs and liver. The presence of metastatic tumors was detected by bioluminescence imaging as well as immunohistochemistry. Taken together, our study suggests that the decrease in anoikis resistance induced by piperlongumine was mediated by STAT-3 inhibition which resulted in reduced tumorigenic as well as metastatic potential of pancreatic cancer cells. Notably, STAT-3 has been shown to be constitutively upregulated in pancreatic cancer rendering it resistant to chemotherapy and potential to metastasize. [Supported in part by R01 grant CA129038 (to S.K.S) awarded by the National Cancer Institute].

Citation Format: Neel Manoj Fofaria, Sanjay K. Srivastava. Inhibition of STAT-3 by piperlongumine induces anoikis, prevents tumor formation in pancreatic cancer in vitro and in vivo. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 1233. doi:10.1158/1538-7445.AM2014-1233
Abstract 1234: Tamoxifen synergizes cytotoxic activity of 4-(E)-{(4-hydroxyphenylimino)-methylbenzene, 1,2-diol} (HPIMBD), a novel resveratrol analogue against breast cancer cells
Authors: Ronghe Amruta Mukund , Chatterjee Anwesha , Abdalla Fatma , Bhat Hari K.
Published: May 2015

Tamoxifen is currently the first line of therapy against estrogen receptor (ER)-positive breast cancers. Prolonged treatment with tamoxifen has been associated with the development of resistant tumor phenotypes. Moreover, this treatment strategy is ineffective against ER-negative breast cancers. In this study, we have investigated the role of 4-(E)-{(4-hydroxyphenylimino)-methylbenzene, 1,2-diol} (HPIMBD), a novel analog of resveratrol, either alone or in combination with tamoxifen on the growth inhibition of breast cancer cells. Breast cancer cell lines MCF-7, T47D, MDA-MB-231 and MDA-MB-468 as well as non-neoplastic breast epithelial cell lines MCF-10A, MCF-10F and HMEC were treated with different doses of HPIMBD or a combination of tamoxifen (2µM) and HPIMBD (at its IC50 dose). Cell proliferation was determined by MTT assays. No effect on cell proliferation was observed upon treatment of non-neoplastic breast cells with HPIMBD. A dose dependent growth inhibition was demonstrated upon treatment of breast cancer cells with HPIMBD. IC50 values of HPIMBD were determined. Tamoxifen at a dose of 2µM showed no effect on the growth of breast cancer or non-neoplastic breast epithelial cell lines. However, a significant increase in inhibition of cellular proliferation of breast cancer cells was demonstrated when tamoxifen (2µM) was used in combination with HPIMBD at its IC50 dose. To investigate the mechanism of inhibition, autophagy markers, beclin-1 and LC3B were quantified by Western blot analyses. The combination treatment significantly increased the expression of autophagy marker beclin-1 and the cleavage of LC3BI to LC3BII. Cell cycle analysis showed an arrest in the S-phase by HPIMBD and G0/G1-phase by tamoxifen. Our studies suggest that a combination of tamoxifen and HPIMBD synergistically inhibit the proliferation of breast cancer cells. Autophagy and cell cycle arrest appear to be the primary mechanisms of inhibition by the combination treatment.

Citation Format: Amruta Mukund Ronghe, Anwesha Chatterjee, Fatma Abdalla, Hari K. Bhat. Tamoxifen synergizes cytotoxic activity of 4-(E)-{(4-hydroxyphenylimino)-methylbenzene, 1,2-diol} (HPIMBD), a novel resveratrol analogue against breast cancer cells. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 1234. doi:10.1158/1538-7445.AM2014-1234
Abstract 1237: Mechanisms of Vernonia amygdalina-induced apoptosis of human breast adenocarcinoma (MCF-7) cells
Authors: Yedjou Clement G. , Tchounwou Paul
Published: May 2015

Breast cancer (BC) is the leading cause of death of women between 40 and 55 years of age and is the second overall cause of death of women. Fortunately, the mortality rate from BC has decreased in recent years due to an increased emphasis on early detection and more effective treatments. Despite early detection and conventional methods of treatment, about 7% of women diagnosed with BC still die every year. Therefore, novel therapeutic agents are needed to improve the clinical outcome of this disease. The development of new drugs from natural products is considered important. Previous studies from our laboratory show that a novel natural product, extracts of Vernonia amygdalina (VA) leaf exerts DNA-damaging anticancer activities against BC. Therefore, the central goal of this research was to determine the therapeutic mechanisms of VA leaf extracts in breast cancer cells. To achieve this goal, cell viability, live and death cells were determined by the means of the MTT assay, trypan blue test, and propidium iodine assay, respectively. Cell apoptosis was measured by flow cytometry analysis of phosphatidylserine externalization (Annexin V assay) and caspase 3 activity, and by DNA laddering assay. Data obtained from the MTT assay indicated that VA significantly reduced the viability of MCF-7 cells a dose-dependent response. On one hand, the Trypan blue dye exclusion test demonstrated the integrity of the membrane of untreated cells in culture. On the other hand, the trypan blue dye exclusion test demonstrated a loss of viability in VA-treated cells due to membrane damage. The result of the propidium iodine demonstrated a significant (p<0.05) increase of necrotic cell death in VA-treated cells, indicative of membrane rupture by VA. Flow cytometry data showed a strong dose-response relationship between VA exposure and Annexin-V positive MCF-7 cells. These results were confirmed by data of DNA laddering assay showing a clear evidence of nucleosomal DNA fragmentation in VA-treated cells. A statistically significant was recorded with regard to caspase 3 activity in MCF-7 cells. Taken together, our research demonstrated that VA represents an apoptosis-inducing agent and its apoptotic mechanisms involve phosphatidylserine externalization, activation of p53 tumor suppressor gene and caspase-3, and nucleosomal DNA fragmentation.

Citation Format: Clement G. Yedjou, Paul Tchounwou. Mechanisms of Vernonia amygdalina-induced apoptosis of human breast adenocarcinoma (MCF-7) cells. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 1237. doi:10.1158/1538-7445.AM2014-1237
Abstract 1240: Bioactive proanthocyanidins from grape seeds inhibit cigarette smoke condensate-enhanced invasion of human non-small cell lung cancer cells by targeting NADPH oxidase and epithelial-mesenchymal transition
Authors: Vaid Mudit , Katiyar Santosh K.
Published: May 2015

Lung cancer is the leading cause of cancer-related deaths in the United States, and the dismal 5-year survival rate of approximately 14% has shown no improvement over the past three decades. Cigarette smoke (CS) is the cause of ∼90% of lung cancer cases, and promotes drug resistance in lung cancer patients and is even known to limit effectiveness of treatment of cancers of other organs. It is therefore important to develop more effective strategies targeting CS-induced molecular abnormalities. Cigarette smoking increases oxidative stress particularly via activation of NADPH oxidase (NOX), a key source of superoxide anion production. Here we report the inhibitory effects of bioactive phytochemicals, grape seed proanthocyanidins (GSPs), on the migration potential of human non-small cell lung cancer (NSCLC) cells (A549, H460 and H1299) and assessed whether CS-induced NOX activation is their target. Using an in vitro invasion assay, we found that treatment of NSCLC cells with CS condensate (CSC) increased the migration of NSCLC cells in a dose-dependent manner, via enhancing NOX mediated-reactive oxygen species (ROS) accumulation. Treatment of NSCLC cells with GSPs inhibited the cell migration via reduction in ROS accumulation or oxidative stress and subsequent reduction of epithelial-to-mesenchymal transition. To examine the molecular targets of GSPs, we studied the effect of GSPs on CSC-induced alterations in the levels of key NOX components, namely, p22phox and p47phox, using A549 cells. We also determined the effect of GSPs on CSC-induced interaction between p22phox and p47phox proteins, a key event in NOX activation. Our results indicate that treatment of A549 cells with GSPs not only reverse CSC-induced expression levels of p22phox and p47phox, but also inhibit CSC-induced NOX activation by decreasing the binding of p22phox and p47phox proteins. This new insight into the anti-lung cancer cell migration activity of GSPs could serve as a basis for chemoprevention or therapy of advanced stage of lung cancer in human patients.

Citation Format: Mudit Vaid, Santosh K. Katiyar. Bioactive proanthocyanidins from grape seeds inhibit cigarette smoke condensate-enhanced invasion of human non-small cell lung cancer cells by targeting NADPH oxidase and epithelial-mesenchymal transition. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 1240. doi:10.1158/1538-7445.AM2014-1240
Abstract 1242: Green tea polyphenols inhibit the growth and induce death of melanoma cells by initiating DNA damage and inhibition of class I histone deacetylases
Authors: Prasad Ram , Katiyar Santosh K.
Published: May 2015

Melanoma remains a leading cause of death from skin diseases due to its propensity to metastasis, and is increasing rapidly in children. Although, melanoma is less common than other types of skin cancers, however, it causes the majority (75%) of skin cancer-related deaths. The average survival of patients with advanced stage of melanoma is less than a year because no effective strategies are available for metastatic melanoma. Since melanoma is a highly malignant cancer, an approach that can inhibit its growth and progression may facilitate the development of an effective strategy for its treatment or prevention. As green tea polyphenols (GTPs) have been shown to have anti-skin carcinogenic effects, we have examined the chemotherapeutic effect of GTPs on the growth of different melanoma cell lines and the molecular mechanisms underlying these effects using an in vitro model. Treatment of melanoma cells (A375 and Hs294t) with GTPs (0, 20, 40 and 60 µg/ml) for 24 and 48 h significantly inhibited histone deacetylase (HDAC) activity, reduced the levels of class 1 HDAC proteins (HDAC 1, 2, 3 and 8) and enhanced histone acetyltransferase (HAT) activity in a dose-dependent manner. These effects of GTPs on melanoma cells were associated with DNA damage, which was evident by Comet assay, and significant reduction in the viability of melanoma cells and induction of cell death. Concomitant treatment of melanoma cells with a proteasome inhibitor, MG132, prevented GTPs-induced degradation of class I HDACs, suggesting that GTPs reduced the levels of HDAC proteins in melanoma cells through proteasomal degradation. Valproic acid, an inhibitor of HDACs, exhibited a similar pattern of reduced viability and induction of death of melanoma cells (A375 and Hs294t). Treatment of A375 and Hs294t cells with GTPs resulted in an alteration of cell cycle regulatory proteins of G0/G1 phase, and that is a decrease in the levels of cyclin D1, D2 and E, and cyclin dependent kinases, CDK2, CDK4 and CDK6 in a dose-dependent manner. Simultaneously, it was also observed that the levels of p21 and p53 proteins were also increased in the cells after the treatment with GTPs, which may have a role in G0/G1 phase arrest and DNA damage. Together, our study provides new insights into the role of class I HDACs in the chemotherapeutic effects of green tea polyphenols on melanoma cells.

Citation Format: Ram Prasad, Santosh K. Katiyar. Green tea polyphenols inhibit the growth and induce death of melanoma cells by initiating DNA damage and inhibition of class I histone deacetylases. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 1242. doi:10.1158/1538-7445.AM2014-1242
Abstract 1249: ERK1/2 targeting with magnolin as a chemopreventive agent
Authors: Lee Cheol-Jung , Lee Mee-Hyun , Lee Ji-Young , Song Ji Hong , Cho Yong-Yeon
Published: May 2015

Mitogen activated protein kinases (MAPKs) play a key role in cell proliferation, cell cycle progression and cell transformation, and activated Ras/ERKs/RSK2 signaling pathways have been widely identified in many solid tumors. In this study, we found that magnolin, a compound found in Magnolia species, directly targeted and inhibited ERK1 and ERK2 kinase activities with IC50 values of 87 nM and 16.5 nM by competing with ATP in an active pocket, respectively. Further, we demonstrated that magnolin inhibited EGF-induced p90RSKs phopshorylation at Thr359/Ser363, but not ERKs phosphorylation at Thr202/Tyr204, resulted in inhibition of cell proliferation by suppression of G1/S cell cycle transition. Additionally, p38 kinases, Jun N-terminal kinases, and Akts did not involved magnolin-mediated inhibitory signaling. Magnolin targeting on ERK1 and 2 activities suppressed the phosphorylation of RSK2 and downstream target proteins including ATF1 and c-Jun and AP-1, a dimer of Jun/Fos, and the transactivation activities of ATF1 and AP-1. Notably, ERKs inhibition by magnolin suppressed EGF-induced anchorage-independent cell transformation and colony growth of RasG12V- harboring A549 human lung cancer cells and NIH3T3 cells stably expressing RasG12V in soft agar. Taken together, these results demonstrated that magnolin might be a naturally occurring chemoprevention and therapeutic agent capable of inhibiting cell proliferation and transformation by targeting ERK1 and ERK2.

Citation Format: Cheol-Jung Lee, Mee-Hyun Lee, Ji-Young Lee, Ji Hong Song, Yong-Yeon Cho. ERK1/2 targeting with magnolin as a chemopreventive agent. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 1249. doi:10.1158/1538-7445.AM2014-1249
Abstract 125: A novel OSM inhibition of cancer metastasis and epithelial-mesenchymal transition in lung adenocarcinoma through STAT1-mediated suppression of Slug
Authors: Pan Chih-Ming , Wang Mong-Lien , Wu Cheng-Wen
Published: May 2015

We previously reported that mesenchymal stem cells (MSCs) secrete a multifunctional cytokine - Oncostatin M (OSM) which effectively inhibited the metastasis and growth of LAC cells, and induced the mesenchymal epithelial transition (MET) pathway, as evidenced by the reduction of several epithelial-mesenchymal transition related markers, including SLUG. However, the underlying mechanism of how OSM mediates the suppression of SLUG is still unknown.

To dissect the downstream effectors of OSM-dependent suppression of SLUG, we individually knocked down STAT1 (STAT1-KD) and STAT3 (STAT3-KD), the two well-known downstream transcription factors activated by OSM, in A549 and CL1-5 cells using lentiviral expressed short hairpin RNAs (shRNA). We demonstrated that knockdown of STAT1, but not STAT3, reversed the OSM suppressed SLUG level and resulted in a higher SLUG mRNA and protein in comparison to scrambled shRNA control. Consistently, knockdown of STAT1 in LAC cells rescued the OSM-mediated inhibition of cell migration, invasion, and proliferation, indicating that STAT1 is the effector of OSM-dependent induction of MET and suppression of cell motility.

Moreover, we constructed SLUG promoter-driven luciferase expression reporters and test the effect of OSM and STAT1 on SLUG promoter activity. We observed that STAT1-KD cells had increased SLUG promoter activity than control cells, while OSM treatment augments this difference. A mutation in the putative STAT1 binding sequence (gamma activated sequence) mapped at -599 bp upstream of STAT1 transcriptional start site diminished the SLUG promoter activity in STAT1-KD cells. We also showed STAT1 binding to SLUG promoter region after OSM treatment by using a chromatin immunoprecipitation assay. These data indicated that the OSM-dependent inhibition of SLUG and elevation of MET signaling is mediated, at least in part, by a STAT1-dependent pathway through a transcriptional control. Our findings revealed a novel paracrine effect of OSM and the underlying mechanism on cancer metastasis and MET in LAC.

Citation Format: Chih-Ming Pan, Mong-Lien Wang, Cheng-Wen Wu. A novel OSM inhibition of cancer metastasis and epithelial-mesenchymal transition in lung adenocarcinoma through STAT1-mediated suppression of Slug. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 125. doi:10.1158/1538-7445.AM2014-125
Abstract 1250: Inhibition of pancreatic carcinogenesis by t-CUPM, a dual inhibitor of c-Raf and soluble epoxide hydrolase
Authors: Liao Jie , Zhang Wanying , Hwng Sung Hee , Li Haonan , Wecksler Aaron T. , Ma Ke , Hammock Bruce D. , Yang Guang-Yu
Published: May 2015

Mutant Kras activated Raf-MAPK/ERK pathway and chronic pancreatitis are the most common pathogenic events involved in human pancreatic carcinogenesis. The soluble epoxide hydrolase (sEH), a pro-inflammatory enzyme, generally inactivates anti-inflammatory epoxyeicosatrienoic acids (EETs). Herein, we have synthesized a novel compound of trans-4-{4-[3-(4-chloro-3-trifluoromethyl-phenyl)-ureido]-cyclohexyloxy}-pyridine-2-carboxylic acid methylamide (t-CUPM) via modifying the central phenyl ring of sorafenib and confirmed its dual inhibition of sEH and c-Raf by recombinant kinase activity assay. Pharmacokinetic analysis revealed that oral dosing of t-CUPM resulted in the higher blood levels than that of sorafenib throughout the complete time course (48 h). The effect of t-CUPM on the development of pancreatitis and pancreatic intraepithelial neoplasia (mPanIN) was determined in the LSL-KrasG12D/Pdx1-Cre mice. The results showed that t-CUPM significantly reduced the severity of chronic pancreatitis, as measured for the extents of acini loss, inflammatory cell infiltration and stromal fibrosis. The progression of low-grade mPanIN I to high grade mPanIN II/III was significantly suppressed by t-CUPM treatment. Inhibition of mutant Kras-transmitted phosphorylations of MEK/ERK was demonstrated in pancreatic tissues and in vitro pancreatic cancer cells by Western blot assay. qPCR analysis revealed that t-CUPM treatment resulted in significantly decreasing the levels of inflammatory cytokines including TNF-α, MCP-1, as well as VCAM-1, and the levels of Shh and GLI1 (Hedgehog pathway). Analysis of eicosanoid profile revealed a significant increase of the EET/DHET ratio that further confirmed sEH inhibition by t-CUPM. These results indicate that simultaneous inhibition of sEH and c-Raf by t-CUPM is important in preventing chronic pancreatitis and carcinogenesis. (supported by NIH R01CA172431)

Note: This abstract was not presented at the meeting.

Citation Format: Jie Liao, Wanying Zhang, Sung Hee Hwng, Haonan Li, Aaron T. Wecksler, Ke Ma, Bruce D. Hammock, Guang-Yu Yang. Inhibition of pancreatic carcinogenesis by t-CUPM, a dual inhibitor of c-Raf and soluble epoxide hydrolase. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 1250. doi:10.1158/1538-7445.AM2014-1250
Abstract 1253: Dual PI3K/mTOR inhibitor NVP-BEZ235 in combination with AKT inhibitor MK2206 in esophageal carcinoma cells
Authors: Yu Hao , Shi Ni , Pan Zui , Chen Tong
Published: May 2015

The long-term goal of our research is to investigate the molecular carcinogenesis of esophageal squamous cell carcinoma and to develop strategies for esophageal cancer prevention. Previous studies in our laboratory demonstrated an association between activation of PI3K/AKT/mTOR pathways and the development of N-nitrosomethylbenzylamine (NMBA)-induced tumors in the rat esophagus. The objective of current study is to evaluate the effects of NVP-BEZ235, a dual PI3K/mTOR inhibitor, and MK2206, an AKT inhibitor, alone or in combination in esophageal cancer cell lines, KYSE-70, -150, -270 and -410. The cancer cell lines were treated with different doses of NVP-BEZ235 (1, 10, 50, 100, 1000 nMol/L) and MK2206 (0.5, 1, 3, 10, 20 uMol/L), or NVP-BEZ235 100 nMol/L plus MK2206 3 uMol/L. Western blot was performed to assess the activation of PI3K/AKT/mTOR pathways. Cell proliferation, apoptosis and cell cycle were analyzed by WST1 and flow cytometry. We found that the combination of NVP-BEZ235 and MK2206 significantly reduced the phosphorylation of p-AKTT308, p-AKTS473, p-mTORS2448, p-S6S235/236 and p-4EBP1T37/46, when compared to NVP-BEZ235 (1000 nMol/L) and MK2206 (20 uMol/L) alone (p<0.05). The cell proliferation rate was reduced by NVP-BEZ235 1000 nMol/L, MK2206 20 uMol/L, or NVP-BEZ235 plus MK2206 to 20% (p<0.01), 24% (p<0.01) and 17% (p<0.01), respectively. The NVP-BEZ235 1000 nMol/L and MK2206 10 uMol/L induced apoptosis in esophageal cancer cells to 30% and 20% (p<0.01), respectively. NVP-BEZ235 plus MK2206 induced apoptosis in esophageal cancer cells to 45% (p<0.01). The combination treatment increased the proportion of cells at G0/G1 phase compared to cells treated with NVP-BEZ235 or MK2206 alone. Our results indicate that co-targeting the PI3K/mTOR and AKT signaling pathways produces synergistic activity against esophageal carcinoma cell growth. This in-vitro study provides evidence to test the efficacy of NVP-BEZ235 in combination with MK2206 in inhibition of esophageal tumor development in vivo. (Supported by NIH/NCI R01 CA131073-01A1).

Citation Format: Hao Yu, Ni Shi, Zui Pan, Tong Chen. Dual PI3K/mTOR inhibitor NVP-BEZ235 in combination with AKT inhibitor MK2206 in esophageal carcinoma cells. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 1253. doi:10.1158/1538-7445.AM2014-1253
Abstract 1254: Novel acetal and halogen oridonin analogues potently induce apoptosis in prostate cancer cell lines via induction of p53/p73 and PUMA expression
Authors: Ke Yu , Liu Zhongbo , Liu Hong-Min , Zi Xiaolin
Published: May 2015

Isodon rubescens (a Chinese herb named “Donglingcao”) has been used as a folk, botanical medicine for treatment of inflammatory diseases and cancer for many years. Oridonin, a complex ent-kaurane diterpenoid that was isolated from this herb, has been demonstrated as a promising anti-cancer agent. However, the anti-cancer potency of oridonin and its in vivo stability remains unsatisfactory for its clinical development. Therefore, we have designed and synthesized a series of acetal and halogen oridonin analogues at the 20 position of the chemical skeleton. All these analogues have demonstrated improved potency over oridonin against the growth of bladder, breast, colon, lung and prostate cancer cell lines with low micromolar to submicromolar IC50 values. In particular, compound 10 potently induces apoptosis in both androgen-sensitive and castration-resistant prostate cancer cell lines, including LAPC4, LNCaP, 22Rv1, PC3 and DU145. Compound 10 increased the expression of YAP1 and its phosphorylation, as well as expression of p73 and p53, which further led to upregulation of p73/p53 target gene PUMA. The apoptotic effect of compound 10 is at least in part dependent on the existence of p53 and PUMA. These results demonstrated the potential of compound 10 as a novel apoptosis inducer for treatment of prostate cancer. The evaluation of the in vivo anti-tumor efficacy of compound 10 is in progress.

Note: This abstract was not presented at the meeting.

Citation Format: Yu Ke, Zhongbo Liu, Hong-Min Liu, Xiaolin Zi. Novel acetal and halogen oridonin analogues potently induce apoptosis in prostate cancer cell lines via induction of p53/p73 and PUMA expression. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 1254. doi:10.1158/1538-7445.AM2014-1254
Abstract 1257: From chemoprevention strategy to identification of potential therapeutic targets and biomarkers for breast cancer
Authors: Ouhtit Allal , Shanmuganathan Somya , Gupta Ishita , Al-Riyami Hamad , Raj Madhwa
Published: May 2015

Over the years, several phyto-compounds have been extensively used in Complementary Alternative Medicine (CAM) studies, individually and often at higher doses to kill cancer cells. Based on the combination and synergism theory, we had previously demonstrated that a combination of Resveratrol and Indole-3-Carbinol synergized and killed a maximum number of Breast Cancer cells. In the present study, we have tested various combinations of 10 well known phytochemicals, used at bioavailable levels, for their effect on cell growth and proliferation of the MDA-MB-231; breast cancer (BC) cell line and MCF-10A; normal breast epithelium as control cell line. The results revealed a super combination of 7 phyto-compounds (7SC), that synergized and induced 100% clearance of the BC cells but did not affect the normal breast epithelial cells. Next, in order to understand the underlying molecular mechanisms of this ‘synergism’ effect, microarray analysis will be conducted on the mRNA collected from the 7SC treated and control cells at 12 and 24 hour time points. Ongoing in vivo experiments aim to evaluate the efficacy of the 7SC phyto-compound treatment in preventing tumor growth using xenograft mouse BC model, and further validate the functional relevance of these genes in BC cell growth and survival. The data supports our hypothesis that the 7SC could be used in CAM as a dietary supplement approach against BC, and further identify genes that have the potential to serve as biomarkers and gene candidate to guide the design of appropriate anti-BC therapeutic strategies.

Note: This abstract was not presented at the meeting.

Citation Format: Allal Ouhtit, Somya Shanmuganathan, Ishita Gupta, Hamad Al-Riyami, Madhwa Raj. From chemoprevention strategy to identification of potential therapeutic targets and biomarkers for breast cancer. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 1257. doi:10.1158/1538-7445.AM2014-1257
Abstract 1258: Knockdown or inhibition of Aldo-keto reductase 1B10 inhibits pancreatic carcinogenesis via modulating Kras-E-cadherin pathway
Authors: Zhang Wanying , Li Haonan , Ma Ke , Liao Jie , Yang Guang-Yu
Published: May 2015

Aldo-keto reductase 1B10 (AKR1B10) is an essential enzyme in the metabolism of carbonyls, retinal and farnesal/geranylgeranial for maintaining cellular homeostasis of retinal-retinoid acid, detoxifying the active carbonyls, and recycling key intermediate products of cholesterol synthesis. All of these biologic processes are crucial contributing to carcinogenesis, particularly the reduction of farnesal/geranylgeranial involves in protein prenylation and for mutant K-ras activity. Mutant K-ras is a most common oncogene in pancreatic cancer, and over expression of AKR1B10 has been identified in pancreatic cancer. To determine the role of AKR1B10 in pancreatic carcinogenesis, silencing of AKR1B10 was achieved in CD18 human pancreatic carcinoma cell line using shRNA knockdown approach. Silencing of AKR1B10 resulted in a significant inhibition of anchor-dependent growth (shRNA AKR1B10 knockdown cells compared to vector-control cells 67 ± 9.5 colonies/HPF vs 170 ± 3.7 colonies/HPF, P < 0.01), invasion index (0.27 vs. 1.00, p<0.05), and cell migration (at 16 hours 9.2 ± 1.2% vs 14.0 ± 1.8%, at 24 hours 21.0 ± 1.1% vs 30.5 ± 3.5%, and at 48 hours 51.9 ± 5.7% vs 88.9 ± 3.0%, P < 0.01). Oleanolic acid (OA), a naturally occurring triterpenoid compound, showed a potent inhibition of AKR1B10 activity and a dose-dependent inhibition of cell growth with IC50 at 30µM. K-ras pull-down and Western blot analysis revealed a significant down-regulation of active form K-ras and phosphorylated C-Raf, and ErK,as well as an up-regulation of E-cadherin by either AKR1B10 knockdown or inhibition. A significant reduction of in vivo tumor growth was observed in nude mice implanted the CD18 pancreatic carcinoma cells with shRNA AKR1B10 knockdown (tumor weight: 0.25 ± 0.06g vs. 0.52 ± 0.07g, P = 0.01), and with AKR1B10 inhibitor OA (tumor weight: 0.35 ± 0.05g vs. 0.52 ± 0.07g, P = 0.05). Our findings indicate AKR1B10 is a unique enzyme involved in pancreatic carcinogenesis possibly via modulation of protein prenylation (KRAS)-E-Cadherin pathway. (supported by NIH R01CA164041)

Note: This abstract was not presented at the meeting.

Citation Format: Wanying Zhang, Haonan Li, Ke Ma, Jie Liao, Guang-Yu Yang. Knockdown or inhibition of Aldo-keto reductase 1B10 inhibits pancreatic carcinogenesis via modulating Kras-E-cadherin pathway. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 1258. doi:10.1158/1538-7445.AM2014-1258
Abstract 1259: Gut microbiota and mucosal inflammation and colorectal neoplasia
Authors: Keku Temitope O. , Bonakdar Romin , Perez Felix Araujo , McCoy Amber N. , Edmundson Patrick , Smith Kevin
Published: May 2015

Colorectal cancer (CRC) is a leading cause of cancer death in the United States. Chronic inflammation has been linked to colorectal neoplasia. More recent studies also implicate imbalances in the gut microbiota (bacteria) CRC. We sought to understand the relationship between the gut microbiota, mucosal inflammation and colorectal adenomas, CRC precursors. We hypothesized that the gut microbiota promotes inflammation via activation of mucosal immune cells to elevate adenoma risk. We examined the relationship between adherent gut bacteria, mucosal immune cells, namely T cells (CD4+ and CD8+), macrophages (CD11b+) and natural killer cells (CD57+) and adenomas in a case control study.

Methods: Participants were consenting screening colonoscopy patients at UNC Hospitals without history or diagnosis of inflammatory bowel disease. Subjects were defined as cases (n=42) or controls (n=35) based on the presence or absence of adenomas. High throughput deep sequencing method was used to assess the microbiota in normal colonic mucosa of cases and controls. Immune cells were assessed by immunohistochemistry and automated image analysis using Aperio software. Differences in microbiota abundance or mucosal immune cell numbers between cases and controls were evaluated by t-tests. Diversity was measured by Shannon diversity. Correlation between bacteria and immune cells was performed using Spearman's correlation.

Results: Cases had higher WHR than controls (p=0.0001). No difference was observed for age, sex, BMI among cases and controls. The abundance of several bacteria taxa differed significantly between cases and controls. We observed a positive relationship between mucosal immune cell density and adenomas. In particular, CD 4+ density and CD4/CD8 ratio were higher in cases than controls (CD4; 1.44 case, 0.69 control p = 0.001; CD4/CD8 1.66 case, 0.56 control, p= 0.002). There were no statistically significant differences in CD 57+, CD11b or CD 8+ cell density between cases and controls. The correlation patterns between the gut microbiota and immune cells differed markedly for cases and controls. There was a positive correlation between Proteobacteria and CD4 or CD4/CD8+ cells among cases but not controls.

Conclusions: our results suggest that the gut bacteria and immune cells are interacting differently depending on adenoma status. These findings suggest activation of mucosal immune cells by bacteria may promote local inflammation and contribute to the etiology of colorectal cancer.

Citation Format: Temitope O. Keku, Romin Bonakdar, Felix Araujo Perez, Amber N. McCoy, Patrick Edmundson, Kevin Smith. Gut microbiota and mucosal inflammation and colorectal neoplasia. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 1259. doi:10.1158/1538-7445.AM2014-1259
Abstract 126: The KISS1 metastasis suppressor appears to integrate glycolysis, mitochondrial biogenesis and metastasis via regulation of a PGC1α pathway
Authors: Liu Wen , Beck Benjamin , Vaidya Kedar S. , Nash Kevin T. , Ballinger Scott W. , Welch Danny R.
Published: May 2015

Considering the enormous energy requirements and stresses of the metastatic cascade, an interrelationship with aerobic glycolysis seems intuitive, but has not been definitively established. The purpose of these studies was to determine whether there is a relationship between KISS1 metastasis suppression and metabolism. Wild-type KISS1 expressed in human melanoma cells were metastasis suppressed and took up less glucose and produced less lactate, corresponding to higher pH[Ex]. Metabolism and metastasis changes did not occur when KISS1 was missing the secretion signal peptide (ΔSS). Changes in glucose transport and key glycolytic enzymes did not consistently correlate with metabolic changes; however, V-ATPase, which promotes extracellular acidification, invasion and metastasis, appears to be involved in KISS1-mediated metabolic changes. Also corresponding with the shift from glycolysis to oxidative phosphorylation, KISS1-expressing cells have 30-50% more mitochondrial mass accompanied increased higher expression of PPARγ co-activator 1α (PGC1α), a master regulator of mitochondrial biogenesis. PGC1α-mediated downstream pathways (i.e. fatty acid synthesis and β-oxidation) are differentially regulated by KISS1, apparently reliant upon direct KISS1 interaction with Nuclear Respiratory Factor 1 (NRF1), a major transcription factor involved in mitochondrial biogenesis. KISS1 does not affect PGC1α mRNA expression but stabilizes the protein through interaction with the ubiquitin-like protein, UBQLN1. To test whether a KISS1- PGC1α axis is critical for metastasis suppressor function, shRNA to KISS1 or PGC1α was introduced into KISS1-expressing cells. Metabolic changes and suppression of invasion and migration were reversed. Importantly, knock-down of PGC1α abolished KISS1-mediated metastasis suppression in vivo, strongly suggesting that PGC1α is an essential downstream mediator of KISS1 as a metastasis suppressor. Taken together, these data define a novel signaling pathway controlling metabolism and metastasis. Moreover, these data appear to directly connect changes in aerobic glycolysis, mitochondrial metabolism, and cancer metastasis.

Citation Format: Wen Liu, Benjamin Beck, Kedar S. Vaidya, Kevin T. Nash, Scott W. Ballinger, Danny R. Welch. The KISS1 metastasis suppressor appears to integrate glycolysis, mitochondrial biogenesis and metastasis via regulation of a PGC1α pathway. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 126. doi:10.1158/1538-7445.AM2014-126
Abstract 1268: High coffee consumption and different brewing methods in relation to postmenopausal endometrial cancer risk in the norwegian women and cancer study: A population-based prospective study
Authors: Gavrilyuk Oxana , Braaten Tonje , Skeie Guri , Weiderpass Elisabete , Dumeaux Vanessa , Lund Eiliv
Published: May 2015

Background

Coffee and its compounds have been proposed to inhibit endometrial carcinogenesis. Studies in the Norwegian population can be especially interesting due to the high coffee consumption and increasing incidence of endometrial cancer in the country.

Methods

A total of 97 926 postmenopausal Norwegian women from the population-based prospective Norwegian Women and Cancer (NOWAC) Study, were included in the present analysis. We evaluated the general association between total coffee consumption and endometrial cancer risk as well as the possible impact of brewing method. Multivariate Cox regression analysis was used to estimate risks, and heterogeneity tests were performed to compare brewing methods.

Results

During an average of 10.9 years of follow-up, 462 incident endometrial cancer cases were identified. After multivariate adjustment, significant risk reduction was found among participants who drank ≥8 cups/day of coffee with a hazard ratio of 0.52 (95% confidence interval, CI 0.34-0.79). However, we did not observe a significant dose-response relationship. No significant heterogeneity in risk was found when comparing filtered and boiled coffee brewing methods. A reduction in endometrial cancer risk was observed in subgroup analyses among participants who drank ≥8 cups/day and had a body mass index ≥25 kg/m2, and in current smokers.

Conclusions

These data suggest that in this population with high coffee consumption, endometrial cancer risk decreases in women consuming ≥8 cups/day, independent of brewing method.

Citation Format: Oxana Gavrilyuk, Tonje Braaten, Guri Skeie, Elisabete Weiderpass, Vanessa Dumeaux, Eiliv Lund. High coffee consumption and different brewing methods in relation to postmenopausal endometrial cancer risk in the norwegian women and cancer study: A population-based prospective study. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 1268. doi:10.1158/1538-7445.AM2014-1268