bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 1746: Discovery and evaluation of a small molecule KIFC1 inhibitor for breast cancer treatment
Authors: Zhang Wei , Zhai Ling , Lu Wenyan , Wang Yimin , Gupta Vandana V. , Padmalayam Indira , Bostwick Robert J. , White Lucile , Larry Ross , Maddry Joseph , Ananthan Sam , Suto Mark , Xu Bo , Li Rongbao , Li Yonghe
Published: August 2015

Historically, drugs used in the treatment of certain cancers may cause damage to healthy cells while affecting cancer cells. Therefore, finding compounds that are specific toward cancer cells only is still a high priority in the search for new therapies. In contrast with normal cells, most cancer cells contain multiple centrosomes which are associated with genome instability and tumorigenesis. Cancer cells can avoid multipolar mitosis which can cause cell death by clustering the extra centrosomes into two spindle poles, thereby enabling bipolar division. Kinesin-like protein KIFC1 plays a critical role in centrosome clustering in cancer cells, but is not essential for normal cell survival. Therefore, targeting KIFC1 may give some insight into how a novel therapy can selectively target only cancer cells. Here, we report that KIFC1 up-regulation is a frequent event in human breast cancer and that KIFC1 is highly expressed in all 8 tested human breast cancer cell lines, but is absent in normal human mammary epithelial cells and weakly expressed in 2 human lung fibroblast lines. We also found that depletion of KIFC1 in breast cancer cells induced cell death. From a high throughput screen of 30,000 compounds, we identified a small molecule KIFC1 inhibitor, SRH06, which has an enzymatic IC50 value of 6.5 μM versus KIFC1 and binds directly to KIFC1 without interacting with the microtubule. Results from our computer modeling studies suggested that SRH06 binds to a novel allosteric site on KIFC1 that appears suitable for the development of selective KIFC1 inhibitors. Importantly, SRH06 prevented bipolar clustering of extra-centrosomes in breast cancer cells and significantly reduced colony formation and cell viability, but was less toxic to normal LL47 fibroblasts. Therefore, SRH06 provides a very valuable tool to study the biological function of KIFC1 and serves as a potential lead for the development of a novel therapeutic agent for the treatment of breast cancer.

Citation Format: Wei Zhang, Ling Zhai, Wenyan Lu, Yimin Wang, Vandana V. Gupta, Indira Padmalayam, Robert J. Bostwick, Lucile White, Ross Larry, Joseph Maddry, Sam Ananthan, Mark Suto, Bo Xu, Rongbao Li, Yonghe Li. Discovery and evaluation of a small molecule KIFC1 inhibitor for breast cancer treatment. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 1746. doi:10.1158/1538-7445.AM2015-1746
Abstract 1750: Preclinical efficacy of Hsp90 inhibition by using PF-04942847 in osteosarcoma
Authors: Baud'Huin Marc , Ory Benjamin , Verrecchia Franck , Heymann Dominique , Redini Francoise , Lamoureux Francois
Published: August 2015

This work was supported by foundation ARC and INSERM, France.

Introduction and Objective: Despite recent improvements in therapeutic management of osteosarcoma, ongoing challenges in improving the response to chemotherapy warrants the development of new strategies to improve overall patient survival. Among new therapeutic approaches, Heat shock protein (HSP) 90 is a molecular chaperone involved in the maturation and stability of various oncogenic proteins leading to tumor cells survival. In this study, we assessed the in vitro and in vivo antitumor properties of a novel synthetic HSP90 inhibitor, PF-04942847 both in vitro and in vivo in osteosarcoma.

Methods: The effects of the HSP90 inhibitor were evaluated in vitro on U2OS, SaOS2, MNNG/HOS, KHOS, MG63, G292, CAL72, SJSA1 and 143B cell growth and apoptosis. The signaling pathways were analyzed by western blotting. The consequence of HSP90 therapy in vivo was evaluated in athymic mice bearing MNNG/HOS xenografts. The effect of PF-04942847 on osteoclastogenesis was assessed in vitro on purified human CD14+ monocytes.

Results: In our panel of osteosarcoma cell lines, PF-04942847 inhibited cell growth in a dose-dependent manner (IC50 ± 50nM) and induced apoptosis with an increase of sub-G1 fraction and PARP cleavage. These biologic events were accompanied by decreased expression of Akt, Erk, MYC, c-MET, STAT-3, and modulation of HSP expression. When administered orally 3 times/week (25mg/kg) to mice bearing osteosarcoma tumors, PF-04942847 significantly inhibited tumor growth by 40% and prolonged survival compared to controls. Moreover, in contrast to 17-AAG, the novel PF-04942847 compound inhibits osteoclast differentiation in vitro.

Conclusions: Targeting HSP90 using PF-04942847 inhibited osteosarcoma tumor growth in vitro and in vivo and appears to inhibit osteoclastogenesis. All these data provides a strong rationale for clinical evaluation of PF-04942847 in osteosarcoma.

Citation Format: Marc Baud'Huin, Benjamin Ory, Franck Verrecchia, Dominique Heymann, Francoise Redini, Francois Lamoureux. Preclinical efficacy of Hsp90 inhibition by using PF-04942847 in osteosarcoma. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 1750. doi:10.1158/1538-7445.AM2015-1750
Abstract 1751: Y15 and Pyridoxal 5′ Phosphate enhances the cytotoxic profile of Cisplatin and Paclitaxel in platinum resistant ovarian cancer cells
Authors: Reboe Monique P. , Waite Terry-ann , Levy Arkene S. , Dhandayuthapani Sivanesan , Rathinavelu Appu
Published: August 2015

Overexpression of the Tyrosine Kinase, Focal Adhesion Kinase (FAK) has been implicated in the development of resistance to front line agents, cisplatin and paclitaxel, in the treatment of ovarian cancer. Moreover vitamins such as Pyridoxal 5′ phosphate (PLP) has been shown to induce cytotoxicity in cancers. Therefore, the aim of this study was to assess the cytotoxic efficacy of FAK inhibition using 1,2,4,5-Benzenetetraamine tetrahydrochloride (Y15) and PLP combined with cisplatin and paclitaxel. Platinum resistant OVCAR-3 cells were treated with varying concentrations of Y15 (10μM, 15 μM, 30 μM, 100 μM), and PLP (0.25mM, 1mM, 2Mm). Cells were also treated with Y15 + PLP, Y15 + Cisplatin + Paclitaxel, PLP + cisplatin + paclitaxel and Cisplatin + paclitaxel for 24 hrs in triplicate and control cells with 2N HCl or media only. The cytotoxic profile of each treatment was assessed using the automated trypan blue assay and DNA fragmentation assay was performed to evaluate the mechanism of cell death. Dose dependent and statistically significant cytotoxicities were seen with Y15 and PLP compared to the controls with IC 50 values 80 μM (p <0.05) and 2 mM (p<0.05) respectively. The use of Y15 in combination with PLP showed enhanced cytotoxic efficacy in OVCAR-3 cell (p<0.0001). Similarly, Y15 significantly increased percentage cell death when combined with cisplatin + paclitaxel (62%, p<0.0001) in comparison to cisplatin + paclitaxel (35%). The use of PLP with cisplatin + paclitaxel also showed a greater cytotoxic profile of 55% (p<0.002). Cell death by apoptosis was not confirmed by DNA fragments in Y15 and PLP positive treatment groups.

Y15 and PLP significantly enhances the cytotoxic profile of cisplatin, paclitaxel in resistant OVCAR-3 cells suggesting that targeting FAK activity through the inhibition of Y397 site and the use of PLP augments resistance to paclitaxel and cisplatin. However further studies are needed to determine the mechanistic pathway of Y15 and Pyridoxal 5′Phosphate induce cytotoxicity.

Citation Format: Monique P. Reboe, Terry-ann Waite, Arkene S. Levy, Sivanesan Dhandayuthapani, Appu Rathinavelu. Y15 and Pyridoxal 5′ Phosphate enhances the cytotoxic profile of Cisplatin and Paclitaxel in platinum resistant ovarian cancer cells. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 1751. doi:10.1158/1538-7445.AM2015-1751
Abstract 1754: BPR2P001S0, a Coumarin derivative, induced cell cycle arrest in A549 through inhibiting PDPK1 activity
Authors: Lin Pi-Han , Jao Tzu-Ming , Hung Yu-Lin , Hsieh Hsing-Pang , Yang Ya-Chien , Chang Sui-Yuan
Published: August 2015

Lung cancer is one of the most common causes of cancer deaths in the world, and the emergence of resistant lung cancer cells can lead to treatment failure. The development of new drugs to treat lung cancer, especially those resistant lung cancer cells, is urgent. Previously we identified that coumarin could inhibit replication of human lung cancer A549 cells. The efficacy of 284 coumarin derivatives on human lung cancer A549 cells was examined, and BPR2P001S0 was the most potent compound. BPR2P001S0 exhibited growth inhibition and apoptotic activity on A549 cells with an IC50 of 10 nM. A similar level of inhibitory effects was also observed in cisplatin-resistant A549 cells (IC50 = 12.5 nM). The ability of colony formation and migration capability of A549 cells decreased significantly in the presence of BPR2P001S0. In cell cycle analysis, BPR2P001S0 induced cell cycle arrest at the G0/G1 phase through down-regulation of cyclin D1 and Cdk4 protein expression. The expression of cyclinD1/Cdk4 regulatory protein, Akt, was also decreased. Subsequently, we found that the expression level of Ser241 phosphorated PDPK1 protein, an Akt activator in Akt pathway, was also reduced. By molecular docking analysis, we found that the reduced PDPK1 phosphorylation is likely resulted from the allosteric effect of interactions between BPRHIV001 and PDPK1. In conclusion, our results suggest that the anti-tumor activity of BPR2P001S0 is likely resulting from its ability to interfere with PDPK1 autophosphorylation at Ser241, which leads to reduced Akt protein and subsequent cyclin D1 degradation.

Citation Format: Pi-Han Lin, Tzu-Ming Jao, Yu-Lin Hung, Hsing-Pang Hsieh, Ya-Chien Yang, Sui-Yuan Chang. BPR2P001S0, a Coumarin derivative, induced cell cycle arrest in A549 through inhibiting PDPK1 activity. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 1754. doi:10.1158/1538-7445.AM2015-1754
Abstract 176: MicroRNA-122 is a potential regulator of DNA methylation partly by affecting the global level profile of 5hmC
Authors: Tsou Ann-Ping , Wang Kuan-Hua , Huang Hsi-Yuan , Chen Li-Jung , Liu Tze-Tze
Published: August 2015

MicroRNA-122 is a liver specific microRNA. Previously, we demonstrated that Mir122a-/- mice developed steatohepatitis, fibrosis and HCC which recapitulates the multistep hepatocarcinogenesis found in human. In addition, we detected a global change of gene expression involving upregulation of 606 genes and downregulation of 280 genes. Among the genes highly differentially expressed in Mir122a-/- livers are several classic imprinted genes H19/Igf2, Meg3, Mirg, Gdf10 and Rian. Imprinting of both H19/Igf2 and Mirg loci is controlled by CTCF, which is a direct target of miR-122. These earlier findings imply that miR-122 may have a role in epigenetic regulation.

Recently, the active demethylation pathway involving 5-hydroxymethylcytosine (5hmC) and TET (tet methylcytosine dioxygenase) enzymes are found to regulate the genome epigenetically. 5hmC epigenetic mark was found to associate with human cancer development with frequent downregulation in cancers, including HCC.

We detected a progressive loss of 5hmC in liver, the tumor-adjacent tissues and liver tumors of Mir122a-/- mice similar to that of human HCC. Loss of 5hmC is accompanied with downregulation of DNA dioxygenase (Tet1 and Tet3), and upregulation of DNA deaminases (Apobec1 and Apobec3) as well as DNA glycosyalse (Smug1) in Mir122a-/- tumors.

A genome-wide profiling of 5hmC was performed to delineate the dynamic changes of DNA methylation. The 5hmC-containing genomic DNA fragments were collected and sequenced. Our preliminary results showed that Mir122a-/- livers appear to have significantly fewer 5hmC peaks and covered smaller portion of the genome than that of WT. Even fewer 5hmC peaks covering small portion of the genome were detected for the Mir122a-/- liver tumor samples. The number of identified 5hmC peaks follows the order of WT > Mir122a-/- (2-month) > tumor-adjacent liver tissue > tumor of Mir122a-/-, a trend that is in agreement with quantification of 5hmC by both IHC and DNA dot blotting.

The preliminary finding that aberrant DNA demethylation was initiated in young Mir122a-/- mice suggests that active demethylation is likely an early event of hepatocarcinogenesis.

Note: This abstract was not presented at the meeting.

Citation Format: Ann-Ping Tsou, Kuan-Hua Wang, Hsi-Yuan Huang, Li-Jung Chen, Tze-Tze Liu. MicroRNA-122 is a potential regulator of DNA methylation partly by affecting the global level profile of 5hmC. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 176. doi:10.1158/1538-7445.AM2015-176
Abstract 1762: Verbascoside promotes apoptosis by regulating HIPK2-p53 signaling in human colorectal cancer
Authors: Zhou Lihong , Feng Yuanyuan , Jin Yongjie , Liu Xuan , Sui Hua , Chai Ni , Chen Xingzhu , Liu Ningning , Wang Yan , Li Qi
Published: August 2015

Background: We investigated the role of the HIPK2-p53 signaling pathway in tumorigenesis and resistance to the drug Verbascoside (VB) in colorectal cancer (CRC), using in vivo and in vitro experiments.

Methods: Primary human CRC samples and normal intestinal tissues from patients were analyzed for HIPK2 expression by immunohistochemistry (IHC) and its expression was correlated against patients’ clinicopathological characteristics. Human CRC HCT-116 cells were implanted in BALB/c nude mice; mice with xenografted tumors were randomly administrated vehicle (control), 20, 40, or 80 mg/mL VB, or 1 mg/mL fluorouracil (5-FU). HIPK2, p53, Bax, and Bcl-2 expression in these tumors were determined by IHC. In vitro effects of VB on CRC cell proliferation and apoptosis were measured by CCK-8 assay and flow cytometry; HIPK2, p53, p-p53, Bax, and Bcl-2 were measured by western blot.

Results: IHC analysis for 100 human CRC tumor samples and 20 normal intestinal tissues, showed HIPK2 expression to inversely correlate with Dukes stage and depth of invasion in CRC (P <0.05). In vivo, the inhibition rates of 20, 40, and 80 mg/mL VB on CRC xenograft tumor weight were 42.79%, 53.90%, and 60.99%, respectively, and were accompanied by increased expression of HIPK2, p53, and Bax, and decreased Bcl-2 expression in treated tumors. In vitro, VB significantly inhibited proliferation of CRC cell lines HCT-116, HT-29, LoVo, and SW620, in a time- and dose-dependent manner. The apoptosis rates of 25, 50, and 100 μM VB on HCT-116 cells were 10.83 ± 1.28, 11.25 ± 1.54, and 20.19 ± 2.87%, and on HT-29 cells were 18.92 ± 6.12, 21.57 ± 4.05, and 25.14 ± 6.73%, respectively. In summary, VB treatment significantly enhanced the protein expression of pro-apoptotic HIPK2, p53, p-p53, Bax, and decreased anti-apoptotic Bcl-2 expression in CRC cells.

Conclusions: HIPK2 protein modulates the phosphorylation status of p53, and levels of Bax and Bcl-2 in CRC. We also found that VB effectively activated the HIPK2-p53 signaling pathway, resulting in increased CRC cells apoptosis.

Note: This abstract was not presented at the meeting.

Citation Format: Lihong Zhou, Yuanyuan Feng, Yongjie Jin, Xuan Liu, Hua Sui, Ni Chai, Xingzhu Chen, Ningning Liu, Yan Wang, Qi Li. Verbascoside promotes apoptosis by regulating HIPK2-p53 signaling in human colorectal cancer. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 1762. doi:10.1158/1538-7445.AM2015-1762
Abstract 1773: MHY-449 induces apoptotic cell death through ROS- and caspase-dependent pathways in AGS human gastric cancer cells
Authors: Choi Yung Hyun , Kang Yong Jung , Kim Seon Hee , Sung Bokyung , Kim Dong Hwan , Hwang Seong Yeon , Kim Minjung , Lim Hyun Sook , Yoon Jeong-Hyun , Moon Hyung Ryong , Chung Hae Young , Kim Nam Deuk
Published: August 2015

We previously reported on the anticancer effect of the diastereoisomeric compound MHY-449, a novel dihydrobenzofuro[4,5-b][1,8] naphthyridin-6-one derivative, in various human cancer cells such as HCT116 human colon cancer cells (Int J Oncol 41: 2057-64, 2012) and PC3 human prostate cancer cells (Int J Oncol 44: 905-11, 2014). In this study, we investigated whether MHY-449 has anticancer properties in AGS human gastric cancer cells, and if so, what the molecular mechanisms are. Treatment with MHY-449 inhibited cell growth and induced apoptotic cell death in a concentration-dependent manner. The induction of apoptosis was determined by morphological changes, Hoechst 33342 staining, DNA fragmentation, increase of late apoptosis and sub-G1 DNA which were detected by flow cytometry analysis. Western blot analysis showed that MHY-449 upregulated the levels of Fas, FasL, p53, p21WAF1/CIP1, p27KIP1 and the ratio of Bax/Bcl-2 and downregulated the levels of procaspase-8, -9 and -3 and the cleavage of poly(ADP-ribose) polymerase (PARP). The apoptotic cell death induced by MHY-449 was accompanied by the activation of caspase-8, -9 and -3, which was completely abrogated by the pan-caspase inhibitor, z-VAD-FMK. In addition, treatment with MHY-449 elevated the level of cellular ROS generation. These data were further confirmed by incubating the cells with N-acetyl-L-cysteine (NAC), which is a scavenger of ROS. Pretreatment with NAC protected against MHY-449-induced cytotoxicity. Similarly, pretreatment of NAC abolished MHY-449-induced downregulation of pro-caspase-8, -9 and -3 and PARP cleavage. Taken together, these findings suggest that MHY-449 induces apoptosis via caspase- and ROS-dependent pathways in AGS human gastric cancer cells.

Citation Format: Yung Hyun Choi, Yong Jung Kang, Seon Hee Kim, Bokyung Sung, Dong Hwan Kim, Seong Yeon Hwang, Minjung Kim, Hyun Sook Lim, Jeong-Hyun Yoon, Hyung Ryong Moon, Hae Young Chung, Nam Deuk Kim. MHY-449 induces apoptotic cell death through ROS- and caspase-dependent pathways in AGS human gastric cancer cells. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 1773. doi:10.1158/1538-7445.AM2015-1773
Abstract 1775: Inhibition of breast cancer cell proliferation by diarylthiourea analog, SL1-18
Authors: Fallatah Maryam , Louie Maggie C. , Liu Shengquan
Published: August 2015

Breast cancer is the most common malignancy that occurs in women in the US and has the second highest cancer-associated mortality rate. Depending on the expression of estrogen receptor α (ERα), breast cancer can be classified as ER positive or negative. Current drugs used to treat ER+ cancers include selective estrogen receptor modulators (SERMs) and selective estrogen receptor down-regulators (SERDs). Unfortunately, prolonged exposure to these drugs often leads to the development of acquired resistance. Consequently, there is a great need to develop alternative therapeutic options. Flexible heteroarotinoids (Flex-Hets) are compounds derived from retinoids that have been shown to display anti-cancer activity. These compounds tend to exhibit lower toxicity in comparison to their retinoid precursor. The objective of this study is to investigate the anti-cancer effects of SL1-18 — a novel heteroarotinoid — on ER+ breast cancer. Our data suggest that treatment of MCF-7 with SL1-18 inhibit cell growth with a GI50 of 5μM. In order to understand the mechanism of action, we evaluated the effects of SL1-18 on the expression of cell cycle regulators, and our results suggest that SL1-18 decreases the expression of cyclin A, cyclin B, cyclin D1 and cdk2. Furthermore, cell cycle analysis revealed that SL1-18 reduces the number of cells going through the S phase when compared to mock-treated controls. Taken together, these preliminary results suggest that the SL1-18 may be a potent inhibitor of breast cancer cell growth, but further research is necessary to determine its mechanism of action.

Citation Format: Maryam Fallatah, Maggie C. Louie, Shengquan Liu. Inhibition of breast cancer cell proliferation by diarylthiourea analog, SL1-18. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 1775. doi:10.1158/1538-7445.AM2015-1775
Abstract 1778: Selectively targeting the DNA-binding domain of the androgen receptor as a prospective therapy for prostate cancer
Authors: Dalal Kush , Roshan-Moniri Mani , Sharma Aishwariya , Li Huifang , Ban Fuqiang , Hassona Mohamed D. , Hsing Michael , Singh Kriti , LeBlanc Eric , Dehm Scott , Tomlinson Guns Emma , Cherkasov Artem , Rennie Paul S.
Published: August 2015

The androgen receptor (AR) is a hormone-activated transcription factor implicated in the development and progression of prostate cancer. The AR contains an N-terminal domain (NTD), followed by DNA binding (DBD) and ligand-binding (LBD) domains. Upon binding of androgens to the LBD, the AR moves into the nucleus where it interacts with target genes via the conserved AR-DBD. Prostate cancer treatment involves the use of small-molecules to block androgen production or to compete with androgens for binding to the AR-LBD. Drug-resistance occurs when LBD mutations render small-molecule treatment ineffective or when constitutively active AR splice variants, lacking the LBD, become overexpressed. We recently identified a surface pocket on the AR-DBD that may serve as an alternative drug-target site. The DBD-specific, small molecule compounds presented here block transcriptional activity of full-length and splice variant AR forms across multiple cell lines and show no cross-reactivity with related steroid nuclear receptors. The inhibition is lost when residues in the binding pocket are mutated or when the AR-DBD is replaced with a different DNA binding domain. Biophysical techniques were used to explore the interaction of these compounds with the purified, recombinant DBD protein. Gene expression analysis demonstrated the down-regulation of AR target genes following compound treatment, without any obvious expression signature associated with toxicity. The compounds affected DNA binding in vitro and also blocked interactions of the AR with chromatin inside the nucleus. Finally, the lead compound suppressed the growth of LNCaP tumor xenografts and was accompanied by down-regulation of AR target genes, such as PSA. These results suggest a mechanism whereby our developed inhibitory compounds interfere with DNA binding by the AR, potentially leading to effective treatment of advanced, castration-resistant prostate cancers.

Citation Format: Kush Dalal, Mani Roshan-Moniri, Aishwariya Sharma, Huifang Li, Fuqiang Ban, Mohamed D. Hassona, Michael Hsing, Kriti Singh, Eric LeBlanc, Scott Dehm, Emma Tomlinson Guns, Artem Cherkasov, Paul S. Rennie. Selectively targeting the DNA-binding domain of the androgen receptor as a prospective therapy for prostate cancer. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 1778. doi:10.1158/1538-7445.AM2015-1778
Abstract 178: Targeting of multiple oncogenic miRNAs on NUMB gene to mediate head and neck carcinogenesis
Authors: Chou Chung-Shan , Chang Kuo-Wei , Lin Shu-Chun
Published: August 2015

Head and neck squamous cell carcinoma (HNSCC) is the 6th leading malignancy in the world. MicroRNAs (miRNAs) are small, non-coding RNAs, which are associated with the genesis and progression of cancers. NUMB is a multi-functional adaptor protein, which can activate E3 ubiquitin ligase and degrade target proteins to modulate pathogenesis. In silico modules predict that miR-31, miR-96, miR-182 and other miRNAs might target NUMB. This study investigates the concordant targeting of multiple oncogenic miRNAs to NUMB, and to verify the roles of NUMB in HNSCC. miR-31, miR-96 and miR-182 were found up-regulated in the vast majority of HNSCC tissues. On the contrary, NUMB expression was largely down-regulated in the tumors. A reverse correlation was noted between miR-31 expression and NUMB expression. Reporter assays using wild type and mutant constructs specified that these oncogenic miRNAs directly target the sequences in the 3′UTR of NUMB gene. However, miR-31 was unable to target a predicted site in the coding sequence of NUMB gene to mediate regulation. Exogenous expression of these miRNAs decreased NUMB expression and increased the migration of HNSCC cells. Knockdown of NUMB expression enhanced oncogenicity of HNSCC cells. However, the exogenous NUMB expression decreased the migration and anchorage-independent growth of HNSCC cells. The oncogenicity induced by these oncogenic miRNAs was attenuated by NUMB expression. This study provides in vitro and in vivo clues demonstrating that miR-31, miR-96 and miR-182 co-target NUMB gene in HNSCC. The coordinative abrogation of these miRNAs together with NUMB enhancement may be contributive to new therapeutic intervention against head and neck cancers.

Citation Format: Chung-Shan Chou, Kuo-Wei Chang, Shu-Chun Lin. Targeting of multiple oncogenic miRNAs on NUMB gene to mediate head and neck carcinogenesis. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 178. doi:10.1158/1538-7445.AM2015-178
Abstract 1782: Post-translational regulation of cyclins by Aspirin through 26S proteasome: Implications in chemoprevention
Authors: Dachineni Rakesh , Ai Guoqiang , Tummala Hemachand , Gunaje Jayarama B.
Published: August 2015

Recent studies have shown that, regular use aspirin for 5 years or more, decreases the occurrence of cancer of the colon, skin, breast, prostate and lung tissues. However, the mechanism of its anti-cancer effects are not completely understood. We hypothesized that Aspirin's chemo preventive action may involve proteins important in the regulation of cell cycle. Using multiple colon and skin cancer cells, we studied whether aspirin modulates the expression of cyclin B1. Cyclin B1 is a regulatory protein involved in mitosis and promotes the passage of cell cycle from G2 to M phase. Cyclin B1 along with Cyclin dependent Kinase 1(CDK1) regulates chromosomal condensation, nuclear envelope break down and spindle pole assembly in early mitosis. We demonstrate that, in HT-29 human colon and Sk-Mel 28 skin cancer cells, aspirin dose dependently decreased the levels of cyclin B1. This was further confirmed using immunofluorescence studies. To determine the involvement of proteases, we determined whether the lactacystin, a 26S proteasomal inhibitor, would reverse the inhibitory effect of aspirin on cyclin B1. We observed that pretreatment of cells with lactacystin completely reversed the decrease in levels of cyclin B1 in aspirin treated cells. Transfection of the DDK tagged cyclin B1 into HT-29 cells were carried out to establish whether the decrease observed occurs through a nuclear independent and post-translational mechanism. We observed that, aspirin significantly decreased the exogenously transfected DDK tagged cyclin B1 protein. Our results, for the first time show that anticancer effects of aspirin may occur through cyclin B1 degradation mediated by 26S proteasomes.

Citation Format: Rakesh Dachineni, Guoqiang Ai, Hemachand Tummala, Jayarama B. Gunaje. Post-translational regulation of cyclins by Aspirin through 26S proteasome: Implications in chemoprevention. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 1782. doi:10.1158/1538-7445.AM2015-1782
Abstract 1790: Caloric restriction can increase the efficacy of radiation in both hormone-sensitive and hormone-resistant prostate cancers by downregulating the IGF-1R pathway
Authors: Han Sunny Y. , Dan Tu D. , De Angelis Tiziana , Han John Y. , Sarich Mak , Carroll Peter , Knudsen Karen , Dicker Adam , Simone Nicole L.
Published: August 2015

Locally advanced prostate cancers (LAPC) are aggressive, have poor prognosis, and are associated with high recurrence rates and conversion to castrate resistance. The molecular underpinnings of LAPC are being investigated to identify novel therapeutics. Animal models have shown that caloric restriction (CR) can potentially prevent the initiation of prostate cancer. We propose that CR may be used as a novel therapeutic intervention to enhance outcomes of radiation treatment by altering the molecular profile of prostate tumors.

To assess the effect of CR with radiation in vivo, eighty 6 week old male nude mice were injected with LNCaP (hormone sensitive) or PC3 (hormone refractory) tumor cells. Once tumors were palpable, mice were randomized to be treated with one of 4 conditions: ad libitum (AL) diet, 8Gy of radiation (RT), 30% reduction in caloric intake (CR), or CR+RT. CR was associated with significant reduction in tumors. After PC3 tumor injection, compared with AL, the mice had a 22% reduction in tumor size with radiation, 77% with CR (p<0.01 by Student's t-test) and an 80% reduction with CR+RT (p<0.01). After LNCaP tumor injection, compared with ad libitum, the mice had a 49% reduction in tumor size with CR and a 55% reduction with CR+RT (p<0.01). Tissue evaluation of mice treated with CR or CR+RT from both the LNCaP and PC3 models revealed decreased proliferation via Ki-67 and increased apoptosis with cleaved caspase-3 levels. In addition, significant downregulation of multiple members of the IGF-1R pathway was seen, including downregulation of IGF-1R, IRS-1, PI3K and pAKT. Serum evaluation revealed decreased IGF-1:IGF-BP3 in serum.

For the first time, we have shown that the efficacy of radiation can be increased by decreasing calories by 30% in both hormone-sensitive and hormone-refractory prostate cancer models. Future clinical trials for both hormone-sensitive and hormone-resistant prostate cancers should consider the innovative use of CR to augment standard cancer therapy as it has the potential to change the biology of tumors and enhance the opportunity for clinical benefit.

Citation Format: Sunny Y. Han, Tu D. Dan, Tiziana De Angelis, John Y. Han, Mak Sarich, Peter Carroll, Karen Knudsen, Adam Dicker, Nicole L. Simone. Caloric restriction can increase the efficacy of radiation in both hormone-sensitive and hormone-resistant prostate cancers by downregulating the IGF-1R pathway. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 1790. doi:10.1158/1538-7445.AM2015-1790
Abstract 1801: Biological validation of a novel high-throughput irradiator for predictive radiation sensitivity bioassays
Authors: Bailey Alison , Fowler Tyler , Nickel Kwangok P. , Bednarz Bryan , Kimple Randall J.
Published: August 2015

Purpose: To improve our ability to study radiation response and screen for radiosensitizing compounds, we have developed a high-throughput variable dose rate microirradiator. We sought to use several assays of radiation induced cellular damage to validate the ability of this system to be used for high-throughput assays.

Methods: Immortalized human tonsillar epithelial cells were cultured in 96-well microtiter plates and irradiated in groups of eight wells to absorbed doses of 0, 1, 2, 4, and 8 Gy. Chloromethyl-H2DCFDA, a fluorescent reactive oxygen species (ROS) marker, was used to measure relative changes in ROS. Single cell gel electrophoresis (aka Comet assay, neutral) was used to detect physical DNA double-strand breaks. High-throughput immunofluorescent microscopy was used to detect γH2AX foci, a early marker of DNA double-strand breaks.

Results: Over the range of radiation doses tested, we confirmed increasing ROS generation as measured by CM-H2DCFDA fluorescence (R2 = 0.969). Over 1,450 comets were analyzed over a range of radiation doses and the Olive Tail Moment (OTM) calculated. A linear increase in OTM with radiation dose was seen (R2 = 0.991). A linear increase in γH2AX foci was seen with increasing radiation dose as measured by cell average γH2AX fluorescence (R2 = 0.999) Conclusions: We have developed a robust platform for high-throughput assays of radiation sensitivity allowing rapid assessment of effects over a range of radiation doses. This system provides a powerful tool for increasing the efficacy of genetic and pharmacologic modifiers of radiation response.

Citation Format: Alison Bailey, Tyler Fowler, Kwangok P. Nickel, Bryan Bednarz, Randall J. Kimple. Biological validation of a novel high-throughput irradiator for predictive radiation sensitivity bioassays. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 1801. doi:10.1158/1538-7445.AM2015-1801
Abstract 1808: Enhancing the Stupp regimen in glioblastoma cancer cells with a T-type calcium channels inhibitor
Authors: Dziegielewski Jaroslaw , Dziegielewska Barbara , Gray Lloyd S.
Published: August 2015

Glioblastoma multiforme (GBM) is the most common and lethal primary brain tumor. Although introduction of the Stupp regimen combining radiation (IR) with concomitant and adjuvant temozolomide (TMZ) led to increased patient survival, the cure rate of GBM is disappointing. We postulated that sensitization of cancer cells to therapy can be achieved by targeting intracellular pathways and processes. Recently, T-type Ca2+ channels have been proposed as a molecular target for GBM sensitization to chemo- and radiotherapy (Keir et al., 2013; Sheehan et al., 2013). In the present studies, we investigated the effects of T-type channel inhibition on GBM cells’ responses to the Stupp regimen. GBM cells differing in their resistance to TMZ and IR were treated with theT-type channel antagonist, mibefradil, either concomitantly with TMZ or sequentially (Interlaced TherapyTM). Cell viability and clonogenic survival were determined, demonstrating significant enhancement of the Stupp regimen's anticancer effects with co-treatment with T-type channels inhibitors. Importantly for DNA-targeted therapies, we observed a decrease in cells’ ability to repair DNA damage in the presence of mibefradil. The molecular mechanism of this decrease was investigated by assessing expression levels, localization and phosphorylation status of ATM, DNA-PK, γH2AX, Chk1/2, Kap1, p53, Rad51. These mechanistic studies demonstrated that inhibiting T-type Ca2+ channels in GBM affects DNA damage signaling and repair through reduction of repair protein activation and changes their cellular localization. The observed effects are specific for T-type channels inhibition, since L-type channels inhibitors had no effect. Our study provide a rational molecular mechanism for sensitization of GBM to the Stupp regimen by T-type Ca2+ channel inhibition, which will facilitate current and future clinical trials and potentially lead to new treatment options for this deadly brain tumor.

Citation Format: Jaroslaw Dziegielewski, Barbara Dziegielewska, Lloyd S. Gray. Enhancing the Stupp regimen in glioblastoma cancer cells with a T-type calcium channels inhibitor. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 1808. doi:10.1158/1538-7445.AM2015-1808
Abstract 1810: Three-dimensional microtissues as phenotypic screening model to identify radiation modifiers for breast cancer
Authors: Anastasov Natasa , Höfig Ines , Radulovic Vanja , Richter Sabine , Lichtenberg Jan , Kelm Jens M. , Thirion Christian , Atkinson Michael J.
Published: August 2015

Among breast cancer patients, radiation therapy resistance is a common problem in treatment. Overcoming the mechanisms responsible for this phenotype is an ongoing challenge. Options include repurposing established chemotherapeutics and the discovery of new radiosensitizing compounds. Three-dimensional (3D) microtissue models offer a physiological environment for efficient preclinical drug testing. We have adopted the 3D microtissue technology (Insphero, AG) to generate highly reproducible mammary cancer microtissues in a 96 well format. Two breast cancer cell lines (T47D and MDA-MB-361) were shown to be able to form 3D spheroids and grow in a reproducible manner over time. Validation of the phenotypic screen using breast cancer 3D microtissues was performed by HER2_shRNA knockdown, exposure to ionizing radiation and a panel of selected chemotherapeutic compounds. HER2_shRNA knockdown and irradiation decelerated growth, as proven by measuring the area of the cell spheroids after treatment. Of ten analyzed chemotherapeutics, vinblastine was the most effective compound, with docetaxel and doxorubicine being less effective in combination with radiation. To investigate the response in a model closer to the in vivo situation we investigated the response of heterotypic 3D microtissues containing both fibroblasts and breast cancer cells. Drug treatment of these heterotypic 3D cultures confirmed treatment with radiation plus vinblastine to be additive in causing breast cancer growth inhibition. Additionally a histological method to embed 3D microtissues in paraffin was established. The expression of the proliferation marker Ki67 and the apoptosis marker active Caspase 3 was evaluated in MDA-MB-361 cells after irradiation and concurrent vinblastine treatment. Such combined treatment caused prominent 3D microtissue damage - defined as extensive staining of active Caspase 3 and less Ki67. This suggests that combining vinblastine and radiation may be an effective radiation sensitizing strategy.

Citation Format: Natasa Anastasov, Ines Höfig, Vanja Radulovic, Sabine Richter, Jan Lichtenberg, Jens M. Kelm, Christian Thirion, Michael J. Atkinson. Three-dimensional microtissues as phenotypic screening model to identify radiation modifiers for breast cancer. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 1810. doi:10.1158/1538-7445.AM2015-1810
Abstract 1811: Correlations of COX2 expressions in circulating tumor cells (CTCs) and response to radiotherapy in head and neck squamous cell carcinoma (HNSCC)
Authors: Wang Feng , Xie Xiaoqi , Wang Zhen , Li Ping
Published: August 2015

Head and neck squamous cell carcinoma (HNSCC) frequently involves metastasis at diagnosis. Circulating tumor cells (CTCs), captured as “liquid biopsy”, can provide real-time clinical information on prognosis, therapy choice and drug response and resistance. Cyclooxygenase 2 (COX-2), a key enzyme involved in prostaglandin production, participates in inflammatory and neoplastic processes. It is expressed by various tumours and contributes to carcinogenesis. Previous study showed that expression of COX2 in HNSCC tumor tissue samples is associated with clinical response to radiotherapy. The aim of study is to investigate whether expression of COX2 in CTCs could be used as a predict factor to clinical response to radiotherapy.An multiplex RNA in situ hybridization (RNA-ISH) method, named CanPatrol CTC enrichment technique, was used to isolate and categorize CTCs as epithelial, biophenotypic epithelial/mesenchyma, and mesenchymal phenotypes. A total of 51 pateints with HNSCC were enrolled into this study and assessed for CTC levels. Of these 51 pateints, 13 patients were evaluated for COX2 expression in CTCs before and after radiotherapy. The COX2 expression in one CTC or more was defined as positive presence. Primary end point was the overall objective response rate. At baseline, CTCs, ranging from 1 to 15, were identified from 36(70.59%) patients, and the median and mean values were 2 and 3(±3 SD) respectively. No significant correlations were observed between CTCs amounts and clinicopathological parameters. Thirteen (25.49%) patients had ≥2 CTCs both at the beginning and the end of treatment. COX2 expressions was identified in 6(46.15%) patients, which associated with ascending mesenchymal rate afterwards, and indicate a trend of less response to radiotherapy. Compared to 46.15% (6/13) of COX2-positive patients, disease control characterized as decreased CTCs/ mesenchymal CTCs after systemic radiotherapy was obtained in 53.85% (7/13) of COX2-negative (p< 0.05). In summary, COX2-positive CTCs is a promising predictive factor for response to radiotherapy.

Citation Format: Feng Wang, Xiaoqi Xie, Zhen Wang, Ping Li. Correlations of COX2 expressions in circulating tumor cells (CTCs) and response to radiotherapy in head and neck squamous cell carcinoma (HNSCC). [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 1811. doi:10.1158/1538-7445.AM2015-1811
Abstract 1814: Effective auger electron radioimmunotherapy using modified anti-HER2 antibody with nuclear localizing signal
Authors: Li Huizi , Hasegawa Sumitaka , Kamada Tadashi , Saga Tsuneo
Published: August 2015

Objective: Radioimmunotherapy has an advantage in treating tumors scattered in the body. Auger electrons have high cell killing effect because of its high LET, and the short range can prevent damages to normal tissue. However, to achieve higher therapeutic effect, it is desirable to deliver Auger electrons into nucleus and locate close to DNA. The use of nuclear localizing signal (NLS) has been proposed to transport Auger electron emitters into nucleus. To evaluate the cytotoxicity of nuclear localized Auger electron emitter, we performed in-vitro assay using 111In-labeled anti-HER2 antibody attached with NLS peptides to human breast cancer cell lines overexpressing HER2.

Material and methods: Trastuzumab, a monoclonal antibody to HER2, was conjugated with CHX-A”-DTPA (DTPA) and derivatized with sulfosuccinimdyl-4-(N-maleimidomethyl) cyclohexane-1carboxylate (sulfo-SMCC) for reaction with synthetic 13-mer NLS peptides (CGYGPKKKRKVGG). 111In was labeled with either trastuzumab-DTPA or NLS-trastuzumab-DTPA, NLS-trastuzumab-DTPA-S carried approximately 4 NLS peptides per antibody and NLS-trastuzumab-DTPA-L carried 10. The radiochemical labeling of 111In-NLS-trastuzumab and 111In-trastuzumab was determined by HPLC. Human mammary epithelial cells HMEpC and two types of human breast cancer cells with low and high HER2 expression, MCF-7 and SKBR3, respectively, were employed for in-vitro study. Nuclear accumulation of 111In was measured in SKBR3 cells by subcellular fraction. Cell viability was evaluated with dye-based cell viability assays in all cell lines. DNA damages were examined with γ-H2AX immunohistochemistry in SKBR3 cells.

Results: Nuclear uptake of 111In was 1.3-1.5-fold higher in SKBR3 cells treated with 111In-NLS-trastuzumab than 111In-trastuzumab and increased depending on the number of NLS peptides. Cell viability was significantly reduced with 111In-NLS-trastuzumab comparing 111In-trastuzumab in SKBR3 cells. Both of 111In-NLS-trastuzumab had little or no cytotoxicity on MCF-7 cells and HMEpC cells. SKBR3 cells treated with 111In-NLS-trastuzumab-L showed more γ-H2AX foci than 111In-trastuzumab.

Conclusions: The cytotoxicity of 111In-NLS-trastuzumab was higher than that of 111In-trastuzumab by inducing more DNA damages in HER2-overexpressing human breast cancer cells. These data demonstrate that delivery of 111In into cell nucleus by anti-HER2 antibody harboring NLS is an effective strategy for targeted cell killing of the human cancer cells overexpressing HER2.

Citation Format: Huizi Li, Sumitaka Hasegawa, Tadashi Kamada, Tsuneo Saga. Effective auger electron radioimmunotherapy using modified anti-HER2 antibody with nuclear localizing signal. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 1814. doi:10.1158/1538-7445.AM2015-1814
Abstract 1816: Impact of 5FU and radiation on replication of interferon-expressing adenovirus
Authors: Sell Jordan
Published: August 2015

Pancreatic Cancer is a disease for which there are very limited efficacious treatments, resulting in a 5-year survival rate for affected patients around only 6%. A recombinant oncolytic adenovirus (OAd-IFN) developed by our group to target pancreatic cancer utilizes enhanced oncolysis with an overexpression of the adenoviral death protein, enhanced infectivity with a genetically modified fiber, conditional replication targeted to pancreatic cancer using the Cox-2 promoter, and an expression of human interferonαto enhance the therapeutic effects of chemotherapy and radiation through the antitumor effects of the cytokine. Our previous work analyzing the therapeutic abilities of IFN expressing vectors in human pancreatic cancer xenografts in immonudeficient nude mice and in syngeneic hamster pancreatic cancer nodules in immunocompetent Syrian hamsters, showed a more evident antitumor effect of OAd-IFN in the latter models. This suggests the success of OAd-IFN as an immune system stimulator, making it a promising candidate for combination therapy approaches. The goal of this study is to investigate the possibility for use of OAd-IFN as a therapy for pancreatic cancer in conjunction with 5FU and radiation. Specifically, the adenoviral replicative ability was measured within pancreatic cancer Mia-Paca 2 cells under various conditions of 5FU and radiation exposure. Replication was analyzed by a correlation to the increase in amount of viral DNA extracted from treated cells at two time points post infection. In two preliminary trials, cells were infected with the virus two days prior to receiving 5FU and radiation, and another group of cells was treated with 5FU before viral infection. Based on the initial data collected, radiation seemed to have no effect on viral replication. 5FU treatment prior to viral infection resulted in an increase in replication at low dose, and a decrease in replication with high dose, however, this effect was only seen at the first time point 3 days after infection. Similarly, 5FU treatment post infection showed a minor dose dependent inhibition of viral replication at high doses, with little to no effect observed in the low dose. Combining viral infection with 5FU appears to have an impact on the replication of OAd-IFN in vitro; however, further trials need to be done to explore the effect of various timing among viral infection and therapy treatments as well as different therapy concentrations and viral titers to further analyze the potential combination therapies.

Citation Format: Jordan Sell. Impact of 5FU and radiation on replication of interferon-expressing adenovirus. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 1816. doi:10.1158/1538-7445.AM2015-1816