bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 4491: Discovery of potent small molecular tubulin inhibitors for the treatment of cancer.
Authors: Cai Sui Xiong , Yu Zenghui , Chen Lei , Xu Qingbing , Wu Lizhen , Liu Lijun , Yin Feng , Wang Guoxiang , Jiang Yangzhen , Zhang Xiuyan , Kong Lingsheng , Bao Qingli , Tian Ye Edward
Published: August 2014

Microtubule is a well-established drug target for the treatment of cancer. Drugs acting at this target include paclitaxel and docetaxel that stabilize the microtubules and prevent cancer cells from going through mitosis. These drugs are very successful chemotherapy agents and widely used for the treatment of cancer. In this presentation, we report the discovery of several series of novel and potent small molecular tubulin inhibitors and the identification of IMP03138 as a preclinical candidate. IMP03138 has advantages over the most commonly used anti-cancer drug paclitaxel in several in vitro assays and in vivo efficacy studies. Importantly, IMP03138 is highly effective against multi-drug resistant cancer cells. IMP3138 is currently undergoing IND enabling studies.

Citation Format: Sui Xiong Cai, Zenghui Yu, Lei Chen, Qingbing Xu, Lizhen Wu, Lijun Liu, Feng Yin, Guoxiang Wang, Yangzhen Jiang, Xiuyan Zhang, Lingsheng Kong, Qingli Bao, Ye Edward Tian. Discovery of potent small molecular tubulin inhibitors for the treatment of cancer. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 4491. doi:10.1158/1538-7445.AM2013-4491
Abstract 4494: MPT0G066, a novel microtubule-destabilizing agent, induces cell apoptosis and potentiates antineoplastic effects of cisplatin in human ovarian cancer cells in vitro and in vivo.
Authors: Chen Chun-Han , Li Ya-Chi , Chang Li-Hsun , Liou Jing-Ping , Pan Shiow-Lin , Teng Che-Ming
Published: August 2014

Ovarian cancer is one of the leading causes of death in women with gynecological malignancy in the United States. About 70% of ovarian cancer cases are diagnosed at an advanced stage resulting in poor survival rate. In the present study, we provide the data showing that MPT0G066, a novel synthetic arylsulfonamide compound, inhibited cell growth and viability in human ovarian cancer cell lines as evidenced by sulphorodamine B (SRB) and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assays. Cell cycle distribution was also determined by flow cytometry, the data revealed that MPT0G066 induced cell cycle arrest at multipolyploidy (MP) phase (SKOV3 cells) or at G2/M phase (A2780 cells) in 24 hours and ultimately increased the cell population in sub-G1 phase in 48 hours. Moreover, in vitro tubulin polymerization assay, in situ labeling of β-tubulin and western blot analysis showed that MPT0G066, similar to colchicine and vincristine, promoted tubulin depolymerization and altered the expression of G2/M cell cycle regulatory proteins. Mechanistically, MPT0G066 induced JNK activation and altered Bcl-2 family proteins by increasing the expression of p-Bcl-2, Bax, Bim, Puma and decreasing the level of Bcl-2 and Mcl-1. Disruption of mitochondrial proteins triggered intrinsic apoptotic pathways through the cleavage of caspase-3, -7, -9, and poly (ADP-ribose) polymerase (PARP). Moreover, treatment with SP600125, a JNK inhibitor, abolished the effects of MPT0G066 on cell viability, Bcl-2 family proteins and apoptotic cell death. Finally, we used xenograft mouse model to demonstrate that MPT0G066 is able to suppress the growth of ovarian carcinoma A2780 cells and potentiated the antineoplastic effects of cisplatin in vivo. Immunohistochemistry data also confirmed MPT0G066-induced JNK activation in tumor sections. In summary, these results suggested that MPT0G066 could disrupt microtubule dynamics, and lead to cell cycle arrest at MP phase or G2/M phase. MPT0G066 induced JNK activation and altered Bcl-2 family proteins, which ultimately caused apoptosis through the intrinsic apoptotic pathways. These finding indicated that MPT0G066 is a potential anticancer agent worthy for further development and may foster novel treatment for patients with ovarian cancer.

Citation Format: Chun-Han Chen, Ya-Chi Li, Li-Hsun Chang, Jing-Ping Liou, Shiow-Lin Pan, Che-Ming Teng. MPT0G066, a novel microtubule-destabilizing agent, induces cell apoptosis and potentiates antineoplastic effects of cisplatin in human ovarian cancer cells in vitro and in vivo. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 4494. doi:10.1158/1538-7445.AM2013-4494
Abstract 4497: TW01001, a novel piperazinedione compound, induces mitotic arrest and autophagy in non-small cell lung cancer A549 cells.
Authors: Chen Mei-Chuan , Wang Hui-Po , Chen Chun-Han , Liu Yi-Nan , Pan Shiow-Ling , Teng Che-Ming
Published: August 2014

Targeting cellular mitosis in tumor cells is an attractive treatment strategy. Here, we report TW01001, a novel compound from the sodium 3-((6-((Z)-((Z)-5-benzylidene-3,6-dioxopiperazin-2-ylidene)methyl)pyridin-3-yloxy)methyl)benzoate, as a new mitotic inhibitor which inhibit tubulin polymerization for non-small cell lung cancer treatment. We focus the detailed mechanism of action of TW01001 in a non-small cell lung carcinoma cell line A549 cells. Treatment of A549 cells with TW01001 caused the cells to accumulate at the G2/M phase of the cell cycle, with a concomitant induction of mitotic phase marker such as MPM2, cyclin B, and phospho-Histone H3. An increase levels of cyclin-dependent kinase 1 (CDK1) Thr161 phosphorylation and bcl-2 Ser70 phosphorylation was found in TW01001-treated cells, suggesting the drug induced CDK1 activity. We showed that the p53 accumulation was detected and was required for the TW01001-induced mitotic arrest. Moreover, TW01001 induced autophagy concentration- and time-dependently by the conversion of microtubule associated protein 1 light chain 3 (LC3-I) to LC3-II and p62/SQSTM1 degradation. After 48 h of TW01001 exposure, apoptotic cell death occurred by revealing caspase-3 activation and PARP cleavage. Notably, blockade of autophagy by either pharmacological inhibitor or siRNAs targeting Atg5 resulted in reduced cytotoxicity in response to TW01001, suggesting that TW01001-induced autophagy led to cell death. Taken together, these results indicated that the combination of autophagy inducers might be attractive for the management of cancer therapy and provides the framework for further development of TW01001 as a new therapeutic agent for lung cancer treatment.

Citation Format: Mei-Chuan Chen, Hui-Po Wang, Chun-Han Chen, Yi-Nan Liu, Shiow-Ling Pan, Che-Ming Teng. TW01001, a novel piperazinedione compound, induces mitotic arrest and autophagy in non-small cell lung cancer A549 cells. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 4497. doi:10.1158/1538-7445.AM2013-4497
Abstract 4498: CKD-516 displays vascular disrupting properties and enhances anti-tumor activity in combination with chemotherapy in a murine tumor model.
Authors: Min Young Joo , Moon Chang Hoon , Lee Seung Ju , Ryu Sang Ryun , Cho Wha Ja , Yoon Nal Ae , Park Sungchan , Cha HeeJeong
Published: August 2014

PURPOSE: CKD-516 is a benzophenone analog with a modification of the B ring, which is replaced by a carbonyl group. The aim of this study is to assess the antivascular effects and the inhibition of cell proliferation of CKD-516.

MATERIALS AND METHODS: To assess the effect of CKD-516 on vascularization, we analyzed the effect on endothelial cells (HUVECs). To determine the inhibition of cell proliferation of CKD-516, we used a lung carcinoma cell line (H460). The alteration of microtubule analyzed using immunoblot, RT-PCR and confocal image. To evaluate the anti-tumor effects of gemcitabine and/or CKD-516, H460 xenograft mice were treated with CKD-516 (2.5 mg/kg) or gemcitabine (40 mg/kg) or CKD-516 + gemcitabine, and tumor growth was compared with vehicle-treated control. For histologic analysis, liver, spleen and tumor tissues were taken at 12 and 24 hours after CKD-516 injection from H460 xenograft mice.

RESULTS: We determined that cytoskeletal changes of HUVECs treated with 10 nM CKD-516 were assessed by immunoblot and confocal imaging. CKD-516 disrupts tubulin assembly and results in microtubule dysfunction inducing cell cycle arrest (G2/M). CKD-516 markedly enhanced the depolymerization of microtubules which may be related to vascular disrupting properties of CKD-516. Interestingly, CKD-516 decreased amount of total tubulin protein in HUVECs. Especially, CKD-516 decreased mRNA expression α-tubulin (HUVECs only) and β-tubulin (HUVECs and H460) at early time point (4 h). Immunocytochemical analysis showed that CKD-516 changed the cellular microtubule network and inhibited the formation of polymerized microtubules. We also showed extensive central necrosis of tumor by 24 h after treated with CKD-516 (2.5 mg/kg, i.p.). In H460 xenograft, CKD-516 combined with gemcitabine significantly delayed tumor growth as compared to control and gemcitabine alone.

CONCLUSION: These results suggest that CKD-516 is a novel agent with vascular disrupting properties, and enhances anti-tumor activity in combination with chemotherapy.

Citation Format: Young Joo Min, Chang Hoon Moon, Seung Ju Lee, Sang Ryun Ryu, Wha Ja Cho, Nal Ae Yoon, Sungchan Park, HeeJeong Cha. CKD-516 displays vascular disrupting properties and enhances anti-tumor activity in combination with chemotherapy in a murine tumor model. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 4498. doi:10.1158/1538-7445.AM2013-4498
Abstract 4499: Total synthesis of tubulysins: A new chemical reaction leads to analogues with enhanced cytotoxicity.
Authors: Vlahov Iontcho , Qi Longwu , You Fei , Hahn Spencer , Santhapuram Hari K. , Wang Kevin , Kleindl Paul , Vaughn Jeremy , Vetzel Marilynn , Reddy Joseph , Leamon Christopher
Published: August 2014

Tubulysins are natural products isolated from myxobacterial species and are mitotic poisons which exceed the cell growth inhibition of any clinically relevant traditional chemotherapeutic. Structurally, tubulysins are linear tetrapeptides comprised of N-methyl pipecolic acid (Mep), isoleucine (Ile), the novel amino acid tubuvaline (Tuv), and the novel tyrosine analogue tubutyrosine (Tut). All isolated tubulysins possess an acid- and base-sensitive N-acyloxymethyl substituent not previously found in nature. This N,O-acetal of formaldehyde is attached as a side chain to the amide N-atom of the Tuv fragment. The isolation of natural tubulysins from culture extracts provides only limited quantities. Recently, we reported a large scale total synthesis of natural tubulysin B. Among the multiple synthetic and stereochemical challenges, the most striking were: a) the incorporation of the labile N,O-diacyl N,O-acetal and b) the regioselective hydrolysis of the C-terminal methyl ester (OMe) in the tripeptide Mep-Ile-Tuv-OMe.

Herein, we present a convergent total synthesis of tubulysin analogues incorporating an alkoxymethyl side chain. Such molecular architecture allows for compounds that are more base and esterase inert, thus providing additional metabolic/catabolic stabilization. The key step in our synthetic strategy relies on use of a novel reagent for the efficient conversion of the N-acyloxymethyl substituent to novel side chain groups with concomitant facilitated hydrolysis of the C-terminal methyl ester. Following LiOH-based hydrolysis of the C-terminal ester, the Tut fragment is added resulting in novel tubulysin analogues.

This novel process opens the door to tubulysin analogs with improved potency for treating cancer.

Citation Format: Iontcho Vlahov, Longwu Qi, Fei You, Spencer Hahn, Hari K. Santhapuram, Kevin Wang, Paul Kleindl, Jeremy Vaughn, Marilynn Vetzel, Joseph Reddy, Christopher Leamon. Total synthesis of tubulysins: A new chemical reaction leads to analogues with enhanced cytotoxicity. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 4499. doi:10.1158/1538-7445.AM2013-4499
Abstract 450: Host-tumor immune response for breast cancer patients.
Authors: Imoto Shigeru , Nakatsugawa Noriko , Isaka Hirotsugu , Ito Hiroki , Imi Kentaro , Miyamoto Kaisuke , Nakatsura Tetsuya
Published: August 2014

We demonstrated immune suppression of regulatory T cells (Treg) and M2 macrophage in breast cancer (BC) patients at AACR 2011. In summary, to compare between 38 early and 12 advanced BC cases, CD163-positive tumor cells and CCR4-positive tumor cells were detected more frequently in advanced cases than in early cases. Treg cells in PBMC significantly increased in percentage of the population in 37 BC patients than in 21 healthy volunteers. To explore host-tumor immune response, several cytokines were examined in the same cases. Plasma from 32 early and 9 advanced BC cases was preoperatively obtained. Human IL-2, IL-4, IL-6, IL-10, TNF, INFγ, and IL-17A were measured using cytometric beads array system. Statistical significance was analyzed using Mann-Whitney U-test. Plasma IL-17A had significantly higher levels in early BC than in advanced BC (103 pg/ml v.s. 51 pg/ml at mean level). Th17 cells may have some potential to control tumor progression in BC. In conclusions, induction of host-tumor immune response due to chemotherapy and anti-HER2 therapy and release from immune suppression such as CCR4 monoclonal antibody are important issues to explore a new strategy for BC patients.

Citation Format: Shigeru Imoto, Noriko Nakatsugawa, Hirotsugu Isaka, Hiroki Ito, Kentaro Imi, Kaisuke Miyamoto, Tetsuya Nakatsura. Host-tumor immune response for breast cancer patients. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 450. doi:10.1158/1538-7445.AM2013-450
Abstract 4500: Tubulin binding agent BPR0L075 induces iitotic catastrophe in paclitaxel-resistant ovarian cancer cells that is independent of caspase-3 activation.
Authors: Liu Xinli , Sun Weimin , Wang Xiaolei , Wu Erxi
Published: August 2014

Paclitaxel resistance is a significant clinical problem. In the current study, we evaluated antiproliferative effects of a tubulin binding agent BPR0L075 in paclitaxel-resistant ovarian cancer cells. BPR0L075 displays potent and broad-spectrum cytotoxicity at low nanomolar concentrations (IC50 = 2-7 nM) against both parental ovarian cancer cells (OVCAR-3, SKOV-3, and A2780-1A9) and paclitaxel-resistant sublines (OVCAR-3-TR, SKOV-3-TR, 1A9-PTX10), regardless of the expression levels of the multidrug resistance transporter P-gp and class III β-tubulin or mutation of β-tubulin. BPR0L075 blocks cell cycle at the G2/M phase in paclitaxel-resistant cells while equal concentration of paclitaxel treatment was ineffective. BPR0L075 induced cell death in paclitaxel-resistant ovarian cancer cells (OVCAR-3-TR and SKOV-3-TR) is primarily due to mitotic catastrophe, evidenced by formation of giant, multinucleated cells and absence of PARP cleavage and DNA fragmentation. Immunoblot analysis shows that survivin protein expression was depleted in resistant cells. BPR0L075 induced cell death in the paclitaxel-resistant ovarian cancer cells proceed through caspase-3 independent mechanisms, supported by the absence of caspase-3 cleavage and ineffectiveness of caspase-3 inhibitor in protecting the resistant cells from BPR0L075 induced cell death. In conclusion, BPR0L075 displays potent cytotoxic effects in ovarian cancer cells with a potential to overcome paclitaxel resistance by bypassing efflux transporters and inducing mitotic catastrophe. BPR0L075 represents a promising antimitotic agent in controlling taxane-resistant ovarian cancer cells.

Citation Format: Xinli Liu, Weimin Sun, Xiaolei Wang, Erxi Wu. Tubulin binding agent BPR0L075 induces iitotic catastrophe in paclitaxel-resistant ovarian cancer cells that is independent of caspase-3 activation. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 4500. doi:10.1158/1538-7445.AM2013-4500
Abstract 4504: Potential use of polyethyleneimine as a gene delivery vehicle for breast cancer.
Authors: Thomas T. J. , Venkiteswaran Sripriya , Thomas Thresia
Published: August 2014

Breast cancer is the second leading cause of cancer death in US women, after lung cancer. A major impediment in advancing gene therapy approaches to breast cancer is the resistance of cancer cell membrane to transport DNA/RNA. Viral vectors are efficient to deliver target genes; however, they are associated with the risk of immune response, random integration into the host genome or recombination with other wild type viruses. In contrast, non-viral vectors, that include lipoplex and polyplex forming carriers, are more advantageous as they are less expensive, easier to manufacture, and can carry large molecules of DNA. Polyethyleneimine (PEI) has emerged as a very effective gene transfection agent. PEI is water soluble, positively charged, and can envelope negatively charged DNA and protect it from lysosomal degradation. However, gene transfection efficacy of PEI for breast cancer cells remains poorly understood. In addition, information on the relationship between the polymer structure and its biological function, such as DNA condensation, toxicity and transfection efficacy is still limited. In this study, we evaluated the transfection efficiency of PEIs differing in molecular weight and branching. pGL3 control plasmid (5256 bp) containing a coding for the firefly luciferase gene driven by the SV40 promoter was used for this study. pGL3 complexed with different PEIs was tested for gene transfection study in breast cancer cells, using luciferase activity measurements with a luminometer. Cytotoxicity was measured by trypan blue exclusion assay. Static and dynamic laser light scattering was used to determine the ability of PEIs to condense plasmid DNA to nanoparticles and determine the size of the nanoparticles. Our results showed maximum transfection efficiency with 22 kDa linear PEI at N/P (nitrogen/phosphorus) ratio of 4.8 to 6. Linear and branched 25 kDa PEIs were less efficient than 22 kDa PEI. Low molecular weight (0.6 and 1.2 kDa) PEIs had negligible effect in transporting plasmid DNA, whereas 10 kDa PEI showed some activity. Cytotoxic effects of the PEIs were suppressed by DNA complexation. Both branched and linear PEIs condensed plasmid DNA to nanoparticles (hydrodynamic radius: ∼155 nm). Taken together, these results demonstrate structure-function relationships of PEIs in condensing and transporting plasmid DNA. Our results might be useful in selecting and improving the properties of PEI as a gene delivery vehicle for breast cancer.

Citation Format: T. J. Thomas, Sripriya Venkiteswaran, Thresia Thomas. Potential use of polyethyleneimine as a gene delivery vehicle for breast cancer. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 4504. doi:10.1158/1538-7445.AM2013-4504
Abstract 4511: An evaluation of the role of Mucin in nano drug delivery.
Authors: Allkholief Musaed , Campbell Robert
Published: August 2014

Introduction: Solid tumors comprise more than 85% of cancers that affect humans. The presence of the extracellular matrix, namely mucin, on the tumor cell is considered one of the barriers against effective treatment of solid tumors. In tumor cells, mucin is aberrantly overexpressed producing a mucin mesh which may impede the rate of entry of chemotherapy medications. The type O-glycosylation inhibitor, benzyl-α-GalNAc, significantly reduces mucin type O-glycosylation in mucin-producing tumor cells resulting in enhanced cytotoxic drug action. We next seek to determine the role of mucin in the delivery of nano-sized drug delivery systems.

Methods: The cell lines used in our studies were derived from tumor or normal tissues representing multiple different tissue environments. A fluorescence microplate reader was used to evaluate the MUC1 expression in the cell lines by using CD227 (anti-MUC1 antibody). We investigated the cellular uptake of the fluorescently labeled polystyrene microsphere beads in Capan-1 (a human pancreatic cancer cell line). The size of these beads was determined by particle size analysis. FACS analysis was used to determine cellular uptake following inhibition of mucin type O-glycosylation and compared to control. Finally, fluorescence microscopy was used to show the effect of inhibitor on the uptake of the beads into ZR-75-1 (a human breast cancer cell line) and Capan-1 cells.

Results: Different levels of mucin expression were observed among the various cell lines. By investigating the antibody association with the MUC1, Capan-1and ZR-75-1have shown the greatest cellular uptake following inhibition of glycosylation. The microspheres used in this study were 920 ±70 nm, 100 ±36 nm, and 52 ±8 nm in size. Cellular uptake studies of the microsphere beads into Capan-1 showed a significant increase in the uptake of the 920 nm beads in cells when compared to control cells. However, in case of the smaller beads, we did not observe a significant increase of the cellular uptake following inhibition of the mucin glycosylation. FACS analysis of the beads with Capan-1 cell line showed a red shift in the fluorescence peak of the 920 nm beads in cells treated with inhibitor compared to control. The smaller beads (52 nm and 100 nm), however, did not show any shift indicating that the uptake of the beads was hindered by the mucin mesh.

Conclusion: Our results suggest that inhibiting the mucin type O-glycosylation alters the uptake of relatively large microsphere beads. This might be helpful in developing a better therapeutic approach to treat cancer.

Citation Format: Musaed Allkholief, Robert Campbell. An evaluation of the role of Mucin in nano drug delivery. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 4511. doi:10.1158/1538-7445.AM2013-4511
Abstract 4512: Super-enhanced permeability and retention (SUPR) effect induced by photo-immunotherapy (PIT) can accommodate massive nano-sized reagents deep into tumors.
Authors: Kobayashi Hisataka , Sano Kohei , Nakajima Takahito , Choyke Peter L.
Published: August 2014

A major barrier to cancer treatment is the inability to deliver sufficient concentrations of drug to the interior of tumors without incurring systemic toxicities. Nanomaterials are appealing because they can carry a large drug payload, however, tumor delivery is limited by modest leakage and retention in most tumors. Photo-immunotherapy (PIT) is a newly developed therapy involving the injection of a conjugate composed of an armed monoclonal antibody (mAb) and a near infrared phthalocyanine dye, IR700 [Mitsunaga M. Nature Med 2011;17:1685]. When exposed to NIR light, the conjugate induces a highly-selective necrotic cell death only in mAb-IR700 bound cancer cells. This target-specific necrotic cell death occurs within 10 minutes of exposure to NIR light and results in rapid morphologic changes including cellular swelling, bleb formation, and rupture of vesicles indicating necrotic cell death. Meanwhile, immediately adjacent receptor-negative cells are unharmed. Because it damages cells immediately adjacent to the tumor vasculature, PIT results in marked increases in vascular permeability leading to 12- to 25-fold enhanced nano-particle delivery into cancer tissue, an effect termed “super-enhanced permeability and retention (SUPR)” to differentiate it from inherent enhanced permeability and retention (EPR). Of particular interest is that nano-sized reagents including macromolecules (dendrimers), particles (quantum dots, iron oxide nano-particles), and liposomes up to 300 nm in diameter rapidly enter and are retained within the tumor space following PIT. Therefore, although PIT might not be able to eliminate all cancer cells due to heterogeneity of tumor antigen expression, SUPR allows the delivery of extremely high concentrations of nano-sized anti-cancer reagents such as daunorubicin containing liposome (Daunoxome), resulted in significantly synergic therapeutic effects of PIT and nano-sized agents. In conclusion, target-selective PIT can induce a SUPR effect leading to the accumulation of relatively high concentrations of nano-sized reagents into the tumor bedthus improving effectiveness of PIT..

Citation Format: Hisataka Kobayashi, Kohei Sano, Takahito Nakajima, Peter L. Choyke. Super-enhanced permeability and retention (SUPR) effect induced by photo-immunotherapy (PIT) can accommodate massive nano-sized reagents deep into tumors. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 4512. doi:10.1158/1538-7445.AM2013-4512
Abstract 4514: Targeted liposomes to pancreatic cancer are effective in controlling the tumor load in mice.
Authors: Kondapalli Lavanya , Lambros Maria P. , Huang Ying
Published: August 2014

Pancreatic cancer is the fourth leading cause of cancer deaths. Targeted drug delivery to pancreas will increase the drug efficacy especially in inoperable tumors and reduce its toxicity. In this study we prepared targeted liposomes to SLC7A11 transporter which is upregulated in pancreatic cancers as our previous work has shown. The objective of our work was to evaluate the antitumor effect of targeted liposomes loaded with daunorubicin (DNR) in a mouse model of pancreatic cancer. Mice C57BL/6 were injected subcutaneously with 1x 106 PanO2 cells. When the tumors became palpable the mice were injected with different targeted or non targeted liposomal formulations of DNR. There were 5 groups: group A, saline; group B, free DNR; group C,DNR encapsulated in non-targeted liposomes; group D, DNR encapsulated in targeted liposomes; group E; DNR encapsulated in targeted liposomes with PEG. DNR dose was 5mg/kg once a week for the first two weeks. Another set of group of mice received a single dose. We measured the tumor size from the day of treatment until the animals were euthanized. On the day of autopsy, tumors were removed, sectioned and placed in a microscope to observe the DNR accumulation. Animals treated with targeted liposomes containing DNR had a significantly lower tumor load compared to those received DNR in nontargeted liposomes. The average body weight of animals that received free DNR shows a decrease which may be due to drug toxicity. Fluorescent images of tumor sections showed that the tumors treated with DNR in targeted liposomes had more fluorescence than tumors treated with free DNR or DNR encapsulated in nontargeted liposomes.The results indicate that DNR encapsulated in the targeted liposomes was more effective in reducing the tumor load compared to free DNR or DNR encapsulated in nontargeted liposomes.

Citation Format: Lavanya Kondapalli, Maria P. Lambros, Ying Huang. Targeted liposomes to pancreatic cancer are effective in controlling the tumor load in mice. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 4514. doi:10.1158/1538-7445.AM2013-4514
Abstract 4516: Targeted delivery of resveratrol to improve therapeutic outcome in prostate cancer.
Authors: Singh Rajesh , Gupta Pranav , Singh Shailesh , Lillard James W.
Published: August 2014

Conventional chemotherapeutics offered to treat prostate cancer (PCa) are not selectively targeted and due to this fact they are toxic to the normal cells. Thus, it is imperative to identify new anti-cancer agents and/or methods to selectively target PCa cells without affecting normal cells. In this regard, resveratrol (trans-3, 5, 4’-trihydroxystilbene), a plant polyphenol, has shown very promising results. Despite the proven anti-tumor effects of resveratrol, clinical use of this compound is restricted due to its poor bioavailability. To surmount these problems, we developed nanoparticles, loaded with resveratrol, using a planetary-balled milling (PBM) technique and tagged them with folate for targeted delivery to PCa cells, which express high affinity folate receptors. Image Stream multispectral imaging was used to measure the response of resveratrol-loaded PBM nanoparticles, and free resveratrol on various PCa cell lines. Resveratrol-loaded folic acid-coated PBM nanoparticles selectively targeted PCa cells and induced apoptosis. Furthermore, our results indicate that targeted delivery of resveratrol using PBM nanoparticles was 70-85% more effective in killing PCa cells at concentrations lower than the IC50 of free resveratrol.

Citation Format: Rajesh Singh, Pranav Gupta, Shailesh Singh, James W. Lillard. Targeted delivery of resveratrol to improve therapeutic outcome in prostate cancer. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 4516. doi:10.1158/1538-7445.AM2013-4516
Abstract 4522: Nanoparticle chemosensitization.
Authors: Sethi Manish , Kowalczyk Sonya R. , Kapadia Chintan H. , Werner Michael E. , Sukumar Rohit , Wang Edina , Wang Andrew Z.
Published: August 2014

Systemic drug toxicity and multi-drug resistance are the two major obstacles in the treatment of cancer. While multi-drug resistance can be easily overcome by the use of chemosensitizers, the process of chemosensitization itself has been shown to be highly toxic to the normal cells. This is because chemosensitizers not only sensitize the tumor tissue but also the normal tissue to the effect of the drug leading to a substantial increase in the systemic toxicity of the drug. On the other hand, nanoparticles (NPs) can decrease systemic toxicity by virtue of their property of preferential accumulation at the site of tumor, making them an ideal candidate for the delivery of the chemosensitizers. We developed a novel method to overcome both of the major obstacles in cancer treatment by synthesizing NP formulations of two potent chemosensitizers, wortmannin (Wtmn) and olaparib. Wtmn is a highly effective PI3 kinase and DNA-PK inhibitor while olaparib is highly potent Poly ADP ribose polymerase (PARP) inhibitor.

NP Wtmn and NP olaparib were synthesized using a biodegradable core-shell NP platform. We studied the chemosensitization effects of NP Wtmn and NP olaparib in vitro using the lung cancer cell lines H23 and H460, and a multi-drug resistant lung cancer cell line H69AR followed by the drug treatment. We used different chemotherapeutic drugs such as etoposide, gemcitabine and docetaxel to demonstrate the effect of NP chemosensitizers. The biodistribution of the NPs was determined using the mouse xenograft model of H460. Normal tissue toxicity was evaluated by using NP chemosensitizers and compared with their small molecule counterparts. Finally, we evaluated NP Wtmn and NP olaparib as a chemosensitizers in vivo using murine xenograft models of H69AR and H460 and compared them to that of free chemosensitizers.

NP chemosensitizers, similar to their small molecule counterparts, are highly potent in vitro in all three cell lines. The biodistribution study showed that NP formulation leads to a higher tumor accumulation when compared to the free molecules. Toxicity study showed significantly less hepatic and hematologic toxicity with NP formulation than the free molecules. In vivo efficacy study demonstrated that NP Wtmn and NP olaparib are potent chemosensitizers and are more effective than their small molecule counterparts. Further, we demonstrated that NP Wtmn can overcome drug resistance in H69AR cell line. Our work demonstrates the proof of principle in utilizing nanomedicine for the improving chemosensitization.

Citation Format: Manish Sethi, Sonya R. Kowalczyk, Chintan H. Kapadia, Michael E. Werner, Rohit Sukumar, Edina Wang, Andrew Z. Wang. Nanoparticle chemosensitization. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 4522. doi:10.1158/1538-7445.AM2013-4522
Abstract 4524: Designer nanoparticles for selective targeting of multiple myeloma and overcoming CAM-DR.
Authors: Kiziltepe Tanyel , Ashley Jonathan , Stefanick Jared , Bilgicer Basar
Published: August 2014

In the continuing search for effective treatments for cancer, here we report the targeting and efficacy studies pursued with a designer multifunctional nanoparticle that combines traditional chemotherapy with cell targeting and anti-cellular-adhesion functionalities to selectively target multiple myeloma (MM) cells and overcome cell adhesion-mediated drug resistance (CAM-DR). Anti-cellular-adhesion evolves as a promising target in oncology. VLA-4-mediated adhesion to the bone marrow extracellular matrix and stromal cells confers MM cells with CAM-DR. In our design, we used micellar nanoparticles as dynamic self-assembling scaffolds to present VLA-4-antagonist peptides and doxorubicin conjugates simultaneously to selectively target MM cells and to overcome CAM-DR. Doxorubicin was conjugated to the nanoparticles through an pH-sensitive hydrazone bond to prevent premature release and thus non-specific toxicity. Peptides were conjugated via a multifaceted synthetic procedure for generating highly effective targeting. Each component of the nanoparticle was purified to >98% purity prior to particle formation, and by controlling the stoichiometries of each component during particle formation, we were able to precisely control the number of targeting functionalities per nanoparticle. The nanoparticles, which exhibited a size of ∼20nm, were efficiently internalized by MM cells with an optimal peptide valency of 20 per micelle, and induced cytotoxicity to MM cells. Mechanistic studies revealed that nanoparticles induced DNA double strand breaks as evidenced by H2AX phosphorylation, and triggered apoptosis, which was associated with PARP and caspase-8 cleavage. Importantly, multifunctional nanoparticles were more efficacious than doxorubicin in the presence of fibronectin (IC50=0.15±0.04 μM and 0.42±0.09 μM, respectively), and overcame CAM-DR induced by adherence of MM cells to fibronectin. Finally, in a MM xenograft model, nanoparticles preferentially homed to MM tumors, with a ∼10 fold more drug accumulation when compared to doxorubicin, and demonstrated dramatic tumor growth inhibition with much reduced overall systemic toxicity. Taken together, we demonstrate the disease-driven engineering of a nanoparticle-based drug delivery system, enabling the model of an integrative approach in the treatment of MM.

Citation Format: Tanyel Kiziltepe, Jonathan Ashley, Jared Stefanick, Basar Bilgicer. Designer nanoparticles for selective targeting of multiple myeloma and overcoming CAM-DR. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 4524. doi:10.1158/1538-7445.AM2013-4524
Abstract 4527: Sensitization of cancer cells to cisplatin by curcumin: mlecular mechanism and drug delivery.
Authors: Daurio Natalie , Tuttle Stephen , Sood Nimil , Hammer Daniel , Koumenis Constantinos
Published: August 2014

Curcumin, the major active component of the spice Turmeric, is known to sensitize cancer cells to treatment with cisplatin. However, the exact mechanism by which this occurs is unresolved. We hypothesize that sensitization is dependent on curcumin-mediated inhibition of thioredoxin reductase 1, a major antioxidant enzyme. We have shown that a knock down of TxnRd1 expression ameliorates sensitization by curcumin and that over-expression of TxnRd1 in cells with low endogenous levels enhances cisplatin sensitivity. The use of curcumin clinically has been limited by is its low bioavailability outside the GI tract. Therefore, we have also encapsulated curcumin into polymersome nanoparticles composed of poly(ethylene oxide)-block-polycaprolactone co-polymer to improve drug delivery. These vesicles have the unique advantage of being completely biodegradable and can be dual loaded with individual drugs in the membrane and aqueous core allowing for simultaneous delivery of curcumin and cisplatin. Preliminary studies have demonstrated that these polymersomes encapsulate both curcumin in the hydrophobic membrane and cisplatin in the aqueous core and can deliver them to tumor cells. Future studies will determine whether these bifunctional polymersomes demonstrate enhanced cytotoxicity to animal models of solid tumors.

Citation Format: Natalie Daurio, Stephen Tuttle, Nimil Sood, Daniel Hammer, Constantinos Koumenis. Sensitization of cancer cells to cisplatin by curcumin: mlecular mechanism and drug delivery. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 4527. doi:10.1158/1538-7445.AM2013-4527
Abstract 4530: Nanoparticle formulation of KU55933 as a potent radiosensitizer.
Authors: Lara Haydee , Foote Michael B. , Wang Edina C. , Sethi Manish , Casbas-Hernandez Patricia , Wang Andrew Z.
Published: August 2014

KU55933 is a potent and specific inhibitor of the Ataxia Telangiectasia Mutated (ATM) protein. Given ATM's critical role in DNA damage repair, specifically double-strand break repair, KU55933 holds high potential as a radiosensitizer. Indeed, previous preclinical studies have demonstrated the radiosentization effect of KU55933. However, clinical translation of KU55933 as a radiosensitizer has been prevented due to concerns of its potential toxicity. Systemic administration of KU55933 would sensitize normal cells as well as cancer cells to the effects of radiotherapy. Such sensitization would not improve the therapeutic index of radiotherapy. Therefore, the key challenge in the translation of KU55933 is to identify methods that can selectively deliver KU55933 to tumors while minimizing normal tissue dose. While traditional drug delivery methods cannot overcome this challenge, the development of nanoparticle (NP) drug delivery vehicles offers a unique opportunity. NPs are known to preferentially accumulate in tumors while provide low drug dose to nearby normal tissues. We hypothesize that NP delivery of KU55933 can not only improve the therapeutic efficacy of KU55933, but also lower its toxicity. In this study, we engineered a NP formulation of KU55933 using a biodegradable lipid-polymer NP. We then compared the radiosensitization effect of NP KU55933 to that of KU55933 in vitro using the non-small cell lung cancer (NSCLC) cell lines H23, A549 and H460. Clonogenic survival assays showed that NP KU55933 is a more potent radiosensitizer than KU55933. The differential radiosensitization effect of both KU55933 formulations was also evaluated in a xenograft mouse model of NSCLC. We validated our in vitro results by demonstrating that NP KU55933 is more effective than KU55933 as radiosensitizer in flank xenograft models of NSCLC. To compare the toxicity of NP KU55933 and KU55933, we determined the skin toxicity after radiotherapy with the two drug formulations. We found lower skin toxicity in mice treated with the NP KU55933 than that for KU55933. In conclusion, our studies demonstrate that NP formulation of KU55933 can enhance the radiosensitization effect and decreases the toxicity in vitro and in vivo. Our results suggest that NP KU55933 holds potential for clinical translation.

Citation Format: Haydee Lara, Michael B. Foote, Edina C. Wang, Manish Sethi, Patricia Casbas-Hernandez, Andrew Z. Wang. Nanoparticle formulation of KU55933 as a potent radiosensitizer. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 4530. doi:10.1158/1538-7445.AM2013-4530
Abstract 4535: Molecular-genetic imaging of prostate cancer.
Authors: Bhatnager Akrita , Gabrielson Kathleen , Fisher Paul B. , Pomper Martin G.
Published: August 2014

Cancer-specific promoters, such as the progression elevated gene-3 or the astrocyte elevated gene promoters, PEG-Prom and AEG-Prom, respectively, can be used as molecular genetic imaging instruments for tumor-selective imaging of cancer. We have previously shown this in experimental models of metastatic breast cancer and melanoma using bioluminescence imaging (BLI) and single photon emission computed tomography with computed tomography (SPECT/CT). Here we show that we can express PEG-Prom and AEG-Prom selectively in PC3-ML (human bone metastatic derived prostate cancer) cells and use these constructs for imaging prostate cancer in vivo. PC3-ML cells were transfected with firefly luciferase (FLuc) or the herpes simplex type I thymidine kinase (HSV1-tk), and validated for suitable transfection through bioluminescence and [125I]FIAU cell uptake assays, respectively. PC3-ML cells were administered through intra-cardiac injection to allow widespread metastases. A linear polyethyleneimine (l-PEI) nanoparticle was used for intravenous (IV) delivery of the promoter constructs to animals bearing metastases. PEG-Prom- and AEG-Prom-driven imaging reporter gene expression was monitored by small animal BLI and by SPECT/CT after IV administration of D-luciferin or [125I]FIAU, respectively. Both BLI and SPECT/CT imaging demonstrated tumor-specific PEG-Prom and AEG-Prom activity in the model of metastatic prostate cancer but not in control. Using the thoracic cavity and tibia as the regions of interest (ROI), quantification of the BLI data (n=6) at the 48 h time point after reporter gene delivery showed a range of 16- to 19-fold higher accumulation of FLuc in the metastasis group compared to control for PEG-Prom and AEG-Prom, respectively. BLI results were confirmed by histopathology, immunohistochemistry and western blot. Quantification of the SPECT/CT data (n=5) at the 56 h time point after reporter gene and 8 h after [125I]FIAU delivery showed a 3- to 11-fold higher accumulation of [125I]FIAU, depending on the tumor burden, in the group bearing metastases compared to control for AEG-Prom. Metastatic nodules detected by the SPECT/CT imaging were confirmed by pathology. The results demonstrate the potential of systemically delivered, PEG-Prom- and AEG-Prom-driven constructs for enabling the imaging of metastatic prostate cancer in vivo.

Citation Format: Akrita Bhatnager, Kathleen Gabrielson, Paul B. Fisher, Martin G. Pomper. Molecular-genetic imaging of prostate cancer. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 4535. doi:10.1158/1538-7445.AM2013-4535
Abstract 4539: Selection of non-phophorylated peptide inhibitors of BRCA1.
Authors: White E. Railey , Ma Zhong , Hacker David E. , Beckta Jason M. , Huie Melissa B. , Williams David C. , Valerie Kristoffer , Hartman Matthew C.
Published: August 2014

A growing body of literature suggests Breast Cancer-Associated Protein 1 (BRCA1) is important not only as a cause, but also as a target in the quest for cancer treatment. BRCA1 deficient cells treated with radiation as well as PARP inhibitors and other chemotherapeutics demonstrate a greater sensitivity than cells with wild type BRCA1. Inhibitors of BRCA1 would take advantage of this synthetic lethality and represent a significant advance in cancer treatment as well as an understanding of the biology of DNA repair. Despite significant study of BRCA1 protein and function, it is a large protein (208 KDa) that is still largely uncharacterized, but its N- and C-terminal domains have been described by significant structural data. The BRCT (BRCA1 C-Terminal) Domain is a phosphoprotein binding domain that is commonly mutated or lost in cancers and has a binding cleft seemingly very suitable for drug design. Small molecule screens have been conducted against this domain, but the resulting hits with moderate affinity have not been shown to induce BRCA1 deficient phenotypes. Phosphopeptides have also been studied as potential BRCA1 inhibitors, yet despite some having affinities in the mid-nanomolar range the presence of a phosphate is not without its pharmacologic challenges. We generated an mRNA display library with 1.3 x 10ˆ13 cyclized peptides covalently attached to the mRNA that encoded them. Eight rounds of selection exposing the library to a GST-BRCT fusion resulted in non-phosphorylated peptides that bind to a BRCT domain of BRCA1. The sequences resulting from the selection have common homologies and initial characterization has shown that these peptides may be the first viable non-phosphoserine containing inhibitors of BRCA1.

Citation Format: E. Railey White, Zhong Ma, David E. Hacker, Jason M. Beckta, Melissa B. Huie, David C. Williams, Kristoffer Valerie, Matthew C. Hartman. Selection of non-phophorylated peptide inhibitors of BRCA1. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 4539. doi:10.1158/1538-7445.AM2013-4539