bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract B04: The effects of saliva exosome-like extracellular vesicles from locally advanced OSCC patients on OSCC cell lines
Authors: Bispo Karina A. , Garcia Fabyane O.T. , Carvalho Tárcia A.C.B. , Mak Milena P. , Castro Gilberto de , Pasini Fatima S.
Published: May 2019

Microvesicles (MV) and exosomes (Ex) are extracellular vesicles (EV) differentiated by size and biogenesis pathway but sharing similar mechanisms of released and fusion with recipient cells. The EVs' tumor cellular derived are implicated in mediating interactions with the cellular environment and are rich sources of biomarkers for noninvasive diagnosis, prognosis, and tumor monitoring. In this work we analyzed the effects of EVs like-exosomes derived from cell-free saliva of locally advanced and unresectable oral squamous cell cancer (OSCC) patients at different stages of disease progression: treatment naive (G1), after treatment and disease free for at least 2 years (G3), and healthy volunteers (G0). EVs were isolated by ultracentrifugation and analyzed by transmission electron microscopy (MET) and Nanosight quantification. The EVs effects on proliferation and migration upon SCC-4 and SCC-25 cell lines were investigated by MTT and scratch-wound assays. EVs exosomes-like were detected in saliva of all groups analyzed without differences in quantity and size distribution. The motility of the SCC-4 cell line was significantly modulated by the vesicles of the different groups analyzed after 12 h of treatment (P<0.05 – ANOVA test). Both SCC-4 and SCC-25 showed similar sensitivity to cisplatin and the addition of EVs apparently decreased this sensitivity. Our preliminary data showed a possible effect of the EVs from OSCC saliva patients on the motility and sensitivity to cisplatin of the oral cell lines. Supported by Fundação de Amparo a Pesquisa (FAPESP 2013/253970).

Citation Format: Karina A. Bispo, Fabyane O.T. Garcia, Tárcia A.C.B. Carvalho, Milena P. Mak, Gilberto de Castro Jr, Fatima S. Pasini. The effects of saliva exosome-like extracellular vesicles from locally advanced OSCC patients on OSCC cell lines [abstract]. In: Proceedings of the AACR International Conference held in cooperation with the Latin American Cooperative Oncology Group (LACOG) on Translational Cancer Medicine; May 4-6, 2017; São Paulo, Brazil. Philadelphia (PA): AACR; Clin Cancer Res 2018;24(1_Suppl):Abstract nr B04.
Abstract B07: CTC and CTM detection in sarcoma patients
Authors: Braun Alexcia C. , Mello Celso A L , Corassa Marcelo P. , Vanessa Alves S. , Abdallah Emne A. , Ulisses Nicolau R. , Díaz Mônica T. M. , Flores Bianca T. C. P. , Fanelli Marcelo F. , Paterlini-Brechót Patrizia , Chinen Ludmilla T. D.
Published: May 2019

Background: Sarcomas represent 1% of all cancers in adults, 8% in adolescents and young people, and 10% in children. Even though it is a rare cancer, it contributes to a significant loss of years of life in comparison with other types of cancer (Amankwah et al., 2013). The presence of isolated circulating tumor cells (CTCs) or circulating tumor microemboli (CTM) in the blood of patients with sarcoma may be early markers of tumor invasion, because it is known that these cells circulate in the blood for months or years before the development of metastases (Paterlini-Brechot and Benali, 2007; Klain, 2009; Rhim et al., 2012).

Objective: To isolate and quantify CTCs and CTM from sarcoma patients, evaluating their presence and correlation with progression-free survival (PFS).

Methods: Blood (approximately 8 mL) was prospectively collected from patients with different types of high-degree sarcoma. Blood was collected before the beginning of chemotherapy. The samples were processed and filtered on ISET (Isolation by Size of Epithelial Tumor Cells, Rarecells, France) system for the isolation and quantification of CTCs and CTMs. Immunocytochemistry (ICC) was later performed with anti-CD45 antibody and counterstained with hematoxylin-eosyn for leucocytes population exclusion. The cutoff was estimated using the maximum of the standardized log-rank statistic proposed by Lausen and Schumacher (1992).

Results: We analyzed 11 high-degree sarcoma patients after metastasis diagnosis, before the beginning of treatment. The median age was 53 years (18-77) and 54.5% were male. The median CTCs number was 2.0 CTCs/mL (1.0-11.0) at baseline. By Kaplan-Meier test, we observed that patients with CTC number below the established cutoff (4.5 CTCs/mL) had better PFS compared to those above the cutoff (7.4 vs. 1.0 months, respectively; P= 0.006). Moreover, patients without CTM had also better PFS compared to those patients with the presence of CTM (7.6 vs. 2.7 months, respectively; P= 0.13).

Conclusion: This is the first study to demonstrate, besides the CTC and CTM presence in sarcoma patients, its real prognostic value, even in a limited sample. Our next step is to characterize these cells to better understand its capability to promote tumor progression.

Citation Format: Alexcia C. Braun, Celso A L Mello, Marcelo P. Corassa, Alves S. Vanessa, Emne A. Abdallah, Nicolau R. Ulisses, Mônica T. M. Díaz, Bianca T. C. P. Flores, Marcelo F. Fanelli, Patrizia Paterlini-Brechót, Ludmilla T. D. Chinen. CTC and CTM detection in sarcoma patients [abstract]. In: Proceedings of the AACR International Conference held in cooperation with the Latin American Cooperative Oncology Group (LACOG) on Translational Cancer Medicine; May 4-6, 2017; São Paulo, Brazil. Philadelphia (PA): AACR; Clin Cancer Res 2018;24(1_Suppl):Abstract nr B07.
Abstract B18: Metabolic signature characterization in prostate cancer mediated by Heme-oxygenase 1
Authors: Arciuch Valeria G. Antico , Anselmino Nicolas , Paez Alejandra , Cascardo Florencia , Cotignola Javier , Gueron Geraldine , Vazquez Elba
Published: May 2019

Prostate cancer (PCa) is the second leading cause of cancer-associated death in men, with bone metastases being the main cause of mortality. Energetic metabolism alterations have become a new hallmark of cancer, since variations in a single gene can orchestrate changes in metabolic pathways and confer an adaptive advantage. Heme-oxygenase 1 (HO-1) exerts an antitumoral role in PCa inhibiting cell proliferation, migration, tumor growth and angiogenesis. The aim of this work was to assess the role of HO-1 in the metabolic signature of PCa.

Through RNA-Seq we found a set of metabolic genes deregulated under pharmacologic induction (hemin treatment) or genetic induction of HO-1 in PC3 cells. STAR and ATP5L2 were found upregulated, while HMGCS2, PRODH and ACOT12 were downregulated. These genes encode for steroid hormone metabolism, ATP synthesis, ketogenesis, proline and lipid metabolism. The analysis of the deregulated genes (2-fold) under HO-1 modulation by Gene Ontology revealed alterations in several metabolic pathways such as steroid, tyrosine and lipid metabolism, and ion transport. Bone is the only site of PCa progression, and bone cells are able to produce factors that increase the growth and survival of tumor cells favoring progression. However, the molecular nature of this interaction remains to be elucidated. Our preliminary results performed on cocultures of PC3 cells (treated or not with hemin) with Raw264.7 (pre-osteoclastic) or MC3T3 (preosteoblastic) cells demonstrate that HO-1 is able to direct the metabolic fate of bone precursor cells due to the deregulation of glycolytic genes. HO-1 induction in PC3 cells downregulated the expression of PKM2 and LDHA in cocultured Raw264.7 and MC3T3 cells (p< 0.05).

Based on our results, we propose HO-1 as a key regulator of the metabolic status of PCa cells and a powerful mediator capable of redefining the metabolic signature of bone precursor cells, thus favoring the establishment of a less aggressive phenotype.

Citation Format: Valeria G. Antico Arciuch, Nicolas Anselmino, Alejandra Paez, Florencia Cascardo, Javier Cotignola, Geraldine Gueron, Elba Vazquez. Metabolic signature characterization in prostate cancer mediated by Heme-oxygenase 1 [abstract]. In: Proceedings of the AACR International Conference held in cooperation with the Latin American Cooperative Oncology Group (LACOG) on Translational Cancer Medicine; May 4-6, 2017; São Paulo, Brazil. Philadelphia (PA): AACR; Clin Cancer Res 2018;24(1_Suppl):Abstract nr B18.
Abstract B32: Translational potential of a small-molecule silibinin in colorectal cancer: Targeting cancer stem cells and their inflammatory niche
Authors: Agarwal Rajesh , Agarwal Chapla
Published: May 2019

The inflammatory milieu of colon cancer stem cell (CSC) niche is also an important growth regulator for both CSC and progenitor cell population. Inflammatory signals, e.g., cytokines arising in CSC niche, due to inflammatory cells in microenvironment, also network with other regulatory pathways to influence the expansion of both cell types. With this background, we aimed to assess whether silibinin, a nontoxic, naturally occurring chemopreventive agent with established preclinical efficacy against growth and progression of colorectal cancer (CRC), has the potential to target colon CSC and associated inflammatory niche during CRC inhibition. Our results found that silibinin strongly decreases the percentage of colonosphere formation (a stem cell characteristic) of CRC cells, and that this effect on colon CSC is mediated via blocking IL-4/6 signaling in CRC cell lines. Silibinin also strongly decreased IL-4/6 induced activation of STAT-3 and NF-kB transcriptional activity, which is associated with decreased mRNA levels of various CSC regulatory molecules, and CSC-associated markers. In other studies, silibinin significantly reduced the booster signals of macrophages towards colon CSC, resulting in decreased colonosphere numbers under both normoxic and hypoxic conditions. Furthermore, we used a colitis-related AOM/DSS-induced colon tumorigenesis model to assess the role of inflammatory conditions on colon CSC generation and expansion, and their modulation by silibinin. Our data indicated the protective effect of oral silibinin feeding in this model in terms of an absence of large macroadenomas (>2-3 mm) in the colon. This effect was accompanied by minimal colonic inflammation (decrease in recruitment of inflammatory cells); tissue analysis indicated a decrease in the expression of proinflammatory cytokines, and associated transcription factors: STAT-3 and NF-kB in the colonic tissues from silibinin group. A decrease in transformed stem cell population (for CSC pool expansion) was also identified by dual staining for BMI-1 and CD44 in the colonic tissues. Together, these results highlight silibinin's potential to interfere with CSC pool expansion by targeting both colon CSC and their inflammatory niche, as well as associated signals involved with the survival and multiplication of colon CSC pool. These findings further support the translational potential and clinical usefulness of silibinin in CRC intervention and therapy. (Supported by R01 CA112304.)

Citation Format: Rajesh Agarwal, Chapla Agarwal. Translational potential of a small-molecule silibinin in colorectal cancer: Targeting cancer stem cells and their inflammatory niche [abstract]. In: Proceedings of the AACR International Conference held in cooperation with the Latin American Cooperative Oncology Group (LACOG) on Translational Cancer Medicine; May 4-6, 2017; São Paulo, Brazil. Philadelphia (PA): AACR; Clin Cancer Res 2018;24(1_Suppl):Abstract nr B32.
Abstract B38: Molecular mechanisms and therapeutic implications of argininosuccinate synthesis 1 regulation in targeted arginine- and glutamine-starvation cancer therapy
Authors: Kuo Macus Tien , Tsai Wen-Bin , Long Yan
Published: May 2019

Argininosuccinate synthetase 1 (ASS1) is the rate-limiting enzyme that catalyzes the biosynthesis of arginine (Arg). Many malignant human tumors are auxotrophic for Arg because ASS1 is silenced. We previously demonstrated that ASS1 is a sensor of Arg auxotrophic response and a chemosensitivity marker for Arg starvation therapy. Upregulation of ASS1 is the primary mechanism of resistance to Arg starvation therapy using Arg-depleting recombinant protein, pegylated arginine deiminase (ADI-PEG20). We will present in this conference that ASS1 is also a sensor for glutamine (Gln)-deprivation response, and that upregulation of ASS1 expression is associated with resistance to Gln-starvation treatments. Knockdown of ASS1 expression resulted in increased sensitivity to both Arg- and Gln-starvation, whereas increased ASS1 expression by ectopic transfection is associated with resistance to both Arg- and Gln-starvation. The addition of permeable fumarate, a metabolite that bridges the tricarboxylic acid and urea cycles, resulted in downregulation of ASS1 expression and increased sensitivity to both Arg- and Gln-deprivation treatments. Metabolically, ASS1 sits in the middle of several metabolic pathways linking Gln and ASS1 metabolism. This may explain how ASS1 can sense both Gln- and Arg-starvation from opposite directions. Mechanistically, the Gln-deprivation response, like the Arg-auxotrophic response, downregulates HIF-1α resulting in de-repression of ASS1. In the meantime, an activator, c-Myc, is upregulated; and the upregulated c-Myc transcriptionally turns on ASS1 expression. We further also demonstrate that Arg starvation-induced c-Myc activation is regulated by the signaling transduction pasthway involving Gas/Axl → PI3 kinase → Akt → GSK3beta → cMyc. Collectively, our results have revealed the molecular basis of auxotropic responses to Arg- and Gln-deprivation, and provided preclinical implications for improving the treatment efficacy of Arg- and Gln-starvation therapies which have been in several current clinical trials. (Supported by NCI grant R01 CA149260.)

Note: This abstract was not presented at the conference.

Citation Format: Macus Tien Kuo, Wen-Bin Tsai, Yan Long. Molecular mechanisms and therapeutic implications of argininosuccinate synthesis 1 regulation in targeted arginine- and glutamine-starvation cancer therapy [abstract]. In: Proceedings of the AACR International Conference held in cooperation with the Latin American Cooperative Oncology Group (LACOG) on Translational Cancer Medicine; May 4-6, 2017; São Paulo, Brazil. Philadelphia (PA): AACR; Clin Cancer Res 2018;24(1_Suppl):Abstract nr B38.
Abstract B42: Safer approaches to colorectal cancer chemoprevention
Authors: Rao Chinthalapally V. , Mohammed Altaf , Janakiram Naveena B.
Published: May 2019

Colorectal cancer (CRC) protective effects of NSAIDs and COX-2 inhibitors are well established; however, they are associated with gastrointestinal (GI) bleeding and enhanced cardiovascular risk. Mechanistic studies suggest that upregulation of 15-PGDH, sparing COX-1/2 and prostaglandin (PG)I2 synthase and/or selectively targeting mPGES-1 and 5-LOX, would reduce the cardiovascular side effects and may improve the chemopreventive efficacy. One unexplored area in colorectal cancer chemoprevention towards safer drug development is limited or no studies on targeting mPGES-1/5LOX. To design and develop selective inhibitors of dual mPGES-1/5-LOX, we used in silico small-molecular docking simulations approaches, and identified LFA-9 as a novel dual mPGES-1/5-LOX inhibitor among >35 analogs. Azoxymethane (AOM)-induced rat colonic tumors were utilized to assess pharmacodynamic inhibitory effects of LFA-9 on mPGES-1 and 5-LOX by Radio-HPLC. At low μM LFA-9 inhibited the mPGES-1 and 5-LOX activities by ~57% and ~68%, respectively. We tested five different doses (100-1,600 ppm) of LFA-9 by modified AIN-76A diet on male C57 mice and observed that <1,600 ppm dietary LFA-9 was found to be safer and free from the liver and GI toxicities. In AOM/DSS-induced colonic inflammation in F344 rat, 200 ppm and above LFA-9 completely abolishes the colonic inflammation and suppresses mPGES-1 and 5-LOX in dose-response manner. Potential CRC preventive efficacy of LFA-9 was assessed AOM-rat carcinogenesis (Aberrant Crypt Foci, (ACF) as surrogate marker in male F344 rats and intestinal tumor inhibition in APCMin/+ mice. In rats, colonic ACF were induced by AOM/DSS treatment, dietary LFA-9 (200, 400, and 600 ppm) showed dose-response (P<0.0001) inhibitory effects on ACFs formation. In APCMin/+ mice study, diet containing 0, 350, and 700 ppm LFA-9 for 14 weeks administration significantly (p<0.0001) reduced total intestinal tumor multiplicity and size dose-dependently in both male and female mice. At high dose both male and female mice showed > 80% suppression of colonic polyps with >2 mm size. Importantly, mice fed with 350-ppm LFA9 showed colon tumor inhibition of 60% (male) and 90% (female). It is noteworthy that both male and female mice fed with 700-ppm LFA-9 showed 91% inhibition of colon tumors. Overall, the above results show that LFA-9 is a novel dual mPGES-1/5-LOX inhibitor, a safer agent and potential for prevention of CRC in high-risk patients. (Grant support: NCI N01-CN 25001-26 and 1R01CA213987-01.)

Citation Format: Chinthalapally V. Rao, Altaf Mohammed, Naveena B. Janakiram. Safer approaches to colorectal cancer chemoprevention [abstract]. In: Proceedings of the AACR International Conference held in cooperation with the Latin American Cooperative Oncology Group (LACOG) on Translational Cancer Medicine; May 4-6, 2017; São Paulo, Brazil. Philadelphia (PA): AACR; Clin Cancer Res 2018;24(1_Suppl):Abstract nr B42.
Abstract B43: Validation of a network-based strategy for the optimization of combinatorial target selection in breast cancer therapy
Authors: Tilli Tatiana Martins , Carels Nicolas , Tuszynski Jack Adam , Pasdar Manijeh
Published: May 2019

Network-based strategies provided by systems biology are attractive tools for cancer therapy. Modulation of cancer networks by anticancer drugs may alter the response of malignant cells and/or drive network reorganization into the inhibition of cancer progression. Previously, using systems biology approach and cancer signaling networks, we identified the top 5 highly expressed and connected proteins (HSP90AB1, CSNK2B, TK1, YWHAB, and VIM) in the invasive MDA-MB-231 breast cancer cell line. Here, we have knocked down the expression of these proteins, individually or together using siRNAs. The transfected cell lines were assessed for in vitro cell growth, colony formation, migration, and invasion relative to control transfected MDA-MB-231, the noninvasive MCF-7 breast carcinoma cell line, and the nontumoral mammary epithelial cell line MCF-10A. The knockdown of the top-5 upregulated connectivity hubs successfully inhibited the in vitro proliferation, colony formation, anchorage independence, migration, and invasion in MDA-MB-231 cells, with minimal effects in the control transfected MDA-MB-231 cells or MCF-7 and MCF-10A cells. The in vitro validation of bioinformatics predictions regarding optimized multitarget selection for therapy suggests that protein expression levels together with protein-protein interaction network analysis may provide an optimized combinatorial target selection for a highly effective antimetastatic precision therapy in triple-negative breast cancer. This approach increases the ability to identify not only druggable hubs as essential targets for cancer survival, but also interactions most susceptible to synergistic drug action. The data provided in this report constitute a preliminary step toward the personalized clinical application of our strategy to optimize the therapeutic use of anticancer drugs.

Citation Format: Tatiana Martins Tilli, Nicolas Carels, Jack Adam Tuszynski, Manijeh Pasdar. Validation of a network-based strategy for the optimization of combinatorial target selection in breast cancer therapy [abstract]. In: Proceedings of the AACR International Conference held in cooperation with the Latin American Cooperative Oncology Group (LACOG) on Translational Cancer Medicine; May 4-6, 2017; São Paulo, Brazil. Philadelphia (PA): AACR; Clin Cancer Res 2018;24(1_Suppl):Abstract nr B43.
Abstract B58: The effect of differential miRNA expression in glioblastoma multiforme molecular subtypes
Authors: Verzola Livia Ferreira Silva , Vidotto Thiago , Squire Jeremy Andrew
Published: May 2019

Glioblastoma multiforme (GBM) is characterized by a distinct profile of specific miRNAs that regulate pathways of therapeutic importance, such as cell proliferation, apoptosis, cell cycle regulation, migration, invasion, and angiogenesis. Recently, the molecular classification of gliomas was updated, and three methylation clusters with distinct prognostic values for GBM were characterized. The aim of this research is to evaluate the expression, the functional roles, and the target genes of the miRNAs that have potential value for diagnosis, prognosis, and treatment in patients within the newest molecular subgroup classification of GBM. First, we performed an in silico analysis 606 GBM samples from the Genome Data Commons (GDC) cohort. Based on the methylation subgroups of gliomas recently published (Cecarelli et al., 2016), we performed a comparison of the miRNA expression between LGm4, LGm5, and LGm6 subgroups through Nexus Expression 3.0 (Biodiscovery). The comparison between LGm4 x LGm6 indicated that eight miRNAs were upregulated, while 17 were downregulated. The LGm5 x LGm4 comparison showed two downregulated miRNAs, and the LGm5 x LGm6 comparison showed one upregulated miRNA. By comparing the differentially expressed miRNAs found in our analysis with two other in silico studies, we found an overlap of 54% of the differentially expressed miRNAs. We will now evaluate the expression levels of the upregulated miRNAs obtained through the in silico analysis of samples of the Hospital of Clinics - Faculty of Medicine of Ribeirão Preto (HCFMRP/USP) through a customized nCounter NanoString panel of 24 miRNA. We will also evaluate the plasma exosomal miRNAs from the same patients using the same 24 miRNA nCounter NanoString panel. By identifying the most significant miRNAs regulating cell proliferation and invasive behavior in this tumor, we will be able to use expression levels of the most informative miRNA to both guide the molecular diagnosis of GBM and facilitate future targeted therapeutics for this aggressive disease.

Citation Format: Livia Ferreira Silva Verzola, Thiago Vidotto, Jeremy Andrew Squire. The effect of differential miRNA expression in glioblastoma multiforme molecular subtypes [abstract]. In: Proceedings of the AACR International Conference held in cooperation with the Latin American Cooperative Oncology Group (LACOG) on Translational Cancer Medicine; May 4-6, 2017; São Paulo, Brazil. Philadelphia (PA): AACR; Clin Cancer Res 2018;24(1_Suppl):Abstract nr B58.
Abstract B69: Study of superoxide dismutase-2 protein in HPV-mediated cell transformation
Authors: Silva Gabriela Ávila Fernandes , Nunes Rafaella Almeida Lima , Boccardo Enrique , Villa Luisa Lina , Termini Lara
Published: May 2019

Oxidative stress reflects an imbalance in the maintenance of the intracellular redox state resulting in the accumulation of oxidant species that may contribute to tumorigenesis. The superoxide dismutase 2 protein (SOD2) contributes to cell homeostasis by catalyzing the dismutation of superoxide anion radicals in oxygen and hydrogen peroxide, preventing the direct inactivation of biomolecules. SOD2 protein can be induced by the activation of the NF-kB pathway in several cell types following treatment with interleukin 1β (IL-1β) and tumor necrosis factor alpha (TNFα), both proinflammatory cytokines. In addition, previous studies from the group have shown a direct correlation between increased levels of SOD2 protein and severity of uterine cervix lesions. The aim of this study is to elucidate the involvement of SOD2 in the pathogenesis associated with HPV and in the effect of proinflammatory cytokines.

Methods: Primary human keratinocytes transduced with HPV16 oncogenes and cervical cancer derived cell lines were treated with the proinflammatory cytokines TNFα, and IL-1beta. The expression of SOD2 protein involved in IL-1 β and TNFα signaling pathways was determined by Western blot and ELISA.

Results: Preliminary results suggest the presence of higher levels of SOD2 expression in uterine cervix-derived tumor cell lines when compared to normal primary keratinocytes. Treatment with IL-1β and TNFα induces SOD2 protein accumulation in in the HPV16 positive cervical-derived tumor line, SiHa. On the other hand, no SOD2 induction was observed in the HPV-negative cervical cancer derived cell line C33. Further replications and additional experiments are needed for conclusions.

Citation Format: Gabriela Ávila Fernandes Silva, Rafaella Almeida Lima Nunes, Enrique Boccardo, Luisa Lina Villa, Lara Termini. Study of superoxide dismutase-2 protein in HPV-mediated cell transformation [abstract]. In: Proceedings of the AACR International Conference held in cooperation with the Latin American Cooperative Oncology Group (LACOG) on Translational Cancer Medicine; May 4-6, 2017; São Paulo, Brazil. Philadelphia (PA): AACR; Clin Cancer Res 2018;24(1_Suppl):Abstract nr B69.
Abstract B77: Perillyl alcohol derivatives as anticancer agents
Authors: Chen Thomas C. , Schonthal Axel H. , Hofman Florence H.
Published: May 2019

The use of the monoterpene perillyl alcohol (POH) for intranasal delivery to brain tumors was first popularized in Brazil. As monotherapy, POH has been found to be nontoxic, and to have anticancer activity in a subset of patients with malignant gliomas. The presumed route of delivery is presumed to be a cranial nerve (olfactory, trigeminal) to brain delivery, bypassing the blood-brain barrier. POH, itself, as a monoterpene is a clear liquid that we have found to be lipophilic in its consistency. We have explored the possibility of taking drugs that are out of patent, but with antibrain tumor activity, chemically conjugating them to POH, and creating a new drug. The process of drug discovery consisted of preclinical determination of: 1) feasibility of chemical conjugation, 2) determination of increased BBB penetrance using a BBB permeability program, 3) determination of functional activity via MTT and colony formation assays, 4) determination of mechanism of action, 5) determination of pharmacokinetic and pharmacodynamics action, and 6) functional activity against intracranial tumors (gliomas, metastatic breast carcinoma, medulloblastomas) demonstrated using established in vivo syngeneic and immune-deficient rodent models. Once these six preclinical steps are validated, formal application for IND status can be prepared by: 1) GMP production of drug, 2) formal toxicity testing using large and small animal models under acute and chronic administration, and 3) clinical trial indication for Phase I/IIa. This method has been successfully employed using temozolomide (TMZ) to create TMZ-POH linked via a carbamate bond (TMZ-POH; NEO212). The same method has been performed for the phosphodiesterase type IV inhibitor rolipram (RP-POH, NEO214), valproic acid (VA-POH; NEO216), 3 bromopyruvate (3BP-POH; NEO218). In each case, we were surprised by the mechanistic differences observed from the native compound to the new drug after POH conjugation. For instance, NEO212 is a DNA-alkylating agent, but with 3x the BBB penetration, 10x the cytotoxic potency, and 3x the stability. This presentation will demonstrate our discovery process using our POH conjugates, and our current IND process for NEO212, which we hope to bring to the clinic in the next 6 months.

Citation Format: Thomas C. Chen, Axel H. Schonthal, Florence H. Hofman. Perillyl alcohol derivatives as anticancer agents [abstract]. In: Proceedings of the AACR International Conference held in cooperation with the Latin American Cooperative Oncology Group (LACOG) on Translational Cancer Medicine; May 4-6, 2017; São Paulo, Brazil. Philadelphia (PA): AACR; Clin Cancer Res 2018;24(1_Suppl):Abstract nr B77.
Abstract IA11: Epigenetic mechanisms in pathogenesis and targeted therapy for B-cell lymphomas
Authors: Melnick Ari
Published: May 2019

Recent genome sequencing studies have revealed that somatic mutation of genes that control the epigenome are the most common class of genetic lesion in DLBCLs and FLs. The epigenome is composed of hundreds of distinct chemical modifications of DNA, histones, RNA, and other molecules. Collectively, the epigenome functions as cellular “software”: instructions that encode and determine the phenotype of every type of normal and malignant cell. The fact that mutations in epigenetic modifiers are so common in DLBCL and FL points to the significance of the epigenome in these tumors. The four most common mutations in epigenetic modifiers in DLBCL and FL affect the following genes: KMT2D (also called MLL2), CREBBP, EP300, and EZH2. Eighty percent of lymphoma patients have at least one of these four mutations and often have more than one. Moreover, these mutations usually occur very early during lymphomagenesis and so represent important “founder” events. One fascinating insight that has recently emerged is that these genes play critical roles in germinal center B cells, which are the cells from which DLBCL and FL arise. This is interesting because in many ways germinal center B cells already manifest tumor-like phenotypes. Indeed, it appears that much of the effect of mutations in KMT2D, CREBBP, EP300, and EZH2 is to “lock” B cells into the germinal center mode, which essentially means that it maintains B cells in a highly proliferative, mutagenic state that is hidden from immune surveillance. Fortunately, novel small-molecule inhibitors have been developed that can correct the abnormal epigenomic programs caused by these mutations, and some of these drugs are already showing efficacy in clinical trials. In addition to suppressing lymphoma cells, this kind of treatment may enhance antilymphoma response by restoring immune surveillance. In my talk I will explain how these mechanisms work, and how we can design and implement novel therapeutic regimens that can suppress lymphoma cells with minimal toxicity to other tissues.

Citation Format: Ari Melnick. Epigenetic mechanisms in pathogenesis and targeted therapy for B-cell lymphomas [abstract]. In: Proceedings of the AACR International Conference held in cooperation with the Latin American Cooperative Oncology Group (LACOG) on Translational Cancer Medicine; May 4-6, 2017; São Paulo, Brazil. Philadelphia (PA): AACR; Clin Cancer Res 2018;24(1_Suppl):Abstract nr IA11.
Abstract IA15: Overcoming drug resistance and tumor heterogeneity in gastrointestinal cancers
Authors: Corcoran Ryan B.
Published: May 2019

Personalized cancer medicine approaches, inhibiting kinases in tumors driven by defined genomic alterations, have demonstrated striking efficacy in many cancer types. However, the development of drug resistance is a major limitation to the efficacy of targeted therapies in oncology. Identifying and understanding the molecular mechanisms driving resistance may foster opportunities to develop therapeutic strategies to overcome resistance. For example, in the ~10% of colorectal cancer patients whose tumors harbor BRAF V600 mutations, we have found that feedback reactivation of MAPK signaling, often mediated by EGFR, underlies the relative insensitivity of these cancers to RAF inhibitors. The development of targeted therapy combination strategies to block feedback reactivation of MAPK signaling has led to marked improvements in response rates for these patients from ~5% to >30% over the past few years. However, in patients who respond to these targeted combinations, the rapid development of acquired resistance still limits clinical benefit. Acquired resistance in BRAF mutant colorectal cancer and in other molecularly defined tumor types can be marked by the development of extensive molecular heterogeneity due to the selection of sub-clonal tumor cell populations, capable of growing under drug pressures, which poses significant diagnostic and therapeutic challenges. We will present data demonstrating how a single-lesion biopsy at disease progression to diagnose the mechanism of acquired resistance can vastly underrepresent the molecular heterogeneity of resistant tumor clones in an individual patient, and may fail to detect the existence of distinct but important resistance mechanisms that can drive mixed or lesion-specific responses and treatment failure to subsequent targeted therapy. By contrast, liquid biopsy approaches analyzing circulating tumor DNA have the potential to detect the presence of simultaneous resistance mechanisms residing in separate metastases in a single patient and to monitor the effects of subsequent therapies on specific sub-clonal tumor cell populations. These findings highlight the critical role of tumor heterogeneity in driving therapeutic resistance and how convergent targeted therapy strategies blocking common signaling nodes capable of overcoming multiple resistance mechanisms may be needed.

Citation Format: Ryan B. Corcoran. Overcoming drug resistance and tumor heterogeneity in gastrointestinal cancers [abstract]. In: Proceedings of the AACR International Conference held in cooperation with the Latin American Cooperative Oncology Group (LACOG) on Translational Cancer Medicine; May 4-6, 2017; São Paulo, Brazil. Philadelphia (PA): AACR; Clin Cancer Res 2018;24(1_Suppl):Abstract nr IA15.
Abstract IA21: PARP trapping and Schlafen 11 to kill cancer cells
Authors: Pommier Yves G. , Murai Junko
Published: May 2019

Poly(ADP-ribose) polymerase inhibitors (PARPIs) kill cancer cells by trapping PARP1 and PARP2. Talazoparib, the most potent PARP inhibitor (PARPI), exhibits remarkable selectivity among the NCI-60 cancer cell lines beyond BRCA inactivation. Our genomic analyses reveal high correlation between response to talazoparib and Schlafen 11 (SLFN11) expression. Causality was established in four isogenic SLFN11-positive and -negative cell lines and extended to olaparib. Response to the talazoparib-temozolomide combination was also driven by SLFN11 and validated in 36 small-cell lung cancer cell lines, and in xenograft models. Resistance in SLFN11-deficient cells was caused neither by impaired drug penetration nor by activation of homologous recombination. Rather, SLFN11 induced irreversible and lethal replication inhibition, which was independent of ATR-mediated S-phase checkpoint. The resistance to PARPIs by SLFN11 inactivation was overcome by ATR inhibition, mechanistically because SLFN11-deficient cells solely rely on ATR activation for their survival under PARPI treatment. Our study reveals that SLFN11 inactivation, which is common (~45%) in cancer cells, is a novel and dominant resistance determinant to PARPIs.

Citation Format: Yves G. Pommier, Junko Murai. PARP trapping and Schlafen 11 to kill cancer cells [abstract]. In: Proceedings of the AACR International Conference held in cooperation with the Latin American Cooperative Oncology Group (LACOG) on Translational Cancer Medicine; May 4-6, 2017; São Paulo, Brazil. Philadelphia (PA): AACR; Clin Cancer Res 2018;24(1_Suppl):Abstract nr IA21.
Abstract A10: Withaferin-A, a natural compound inhibits AKT-induced metastatic colorectal cancer
Authors: Suman Suman , Das Trinath P. , Damodaran Chendil
Published: May 2019

The survival rate of metastatic colorectal carcinoma (CRC) is less than 5%. Use of 5-fluorouracil (5-FU), radiation, and surgery are the primary treatments; however, most metastatic cancers eventually cause death. Developing approaches to prevent progression to metastasis could therefore be part of an important therapeutic strategy, especially for high-risk patients, including those patients already diagnosed with high grade polyps or localized colon cancer. In our preclinical and clinical data, we hypothesized that accumulation of AKT (protein kinase-B) is a critical step in the aggressive phenotype of disease. The metastatic cascade of CRC involves the crucial process of the epithelial–mesenchymal transition (EMT), which endows cancer cells with migratory and invasive capabilities via acquisition of a mesenchymal phenotype. These characteristics also contribute to cellular resistance to chemotherapeutic drugs.

Withaferin-A (WA) is a potent herbal molecule from withania sominefera herbal plant, inhibited CRC growth by down regulating AKT signaling. Furthermore, over expression of AKT significantly increased cell proliferation, aggressiveness and angiogenesis of colon tumors in xenograft models. However, WA overcomes AKT mediated growth in both cell culture and animal models by transcriptionally down regulating Epithelial Mesenchymal Transition (EMT) related transcription factors and genes such as Snail, Slug and β-catenin. We also found AKT expression is steadily increased in CRC patients in a stage specific manner, suggesting accumulation of AKT could be a critical step for CRC metastasis. We found that WA binds to AKT with a predicted affinity of -10.6 kcal/mol and inhibited its activation. We have identified several novel WA–derived analogs which may be more potent than the parental compound with high AKT binding affinity. We have identified a potent analog which inhibited AKT kinase activity and induced growth arrest (~30 times potent) more significantly than WA. Currently, we are testing the invivo efficacy of the potent analog of WA, which could be a used as a novel agent for chemoprevention and/or chemotherapy of colon cancer.

Citation Format: Suman Suman, Trinath P. Das, Chendil Damodaran. Withaferin-A, a natural compound inhibits AKT-induced metastatic colorectal cancer. [abstract]. In: Proceedings of the Twelfth Annual AACR International Conference on Frontiers in Cancer Prevention Research; 2013 Oct 27-30; National Harbor, MD. Philadelphia (PA): AACR; Can Prev Res 2013;6(11 Suppl): Abstract nr A10.
Abstract A31: Omega-3 fatty acids may regulate levels of pAkt through a mechanism independent of PI3K
Authors: Zhu Lingji , Marsacarinas Windel Emman T. , Principe Daniel R. , Grippo Paul J.
Published: May 2019

The effects of dietary factors on pancreatic cancer have been proposed to augment etiology of disease, yet the mechanisms involved are poorly understood. Our previous work demonstrated that omega-6 fatty acid rich diets have been associated with increased severity of pancreatic neoplasia, but conversely, omega-3 fatty acid rich diets have chemoprotective effects against Kras-induced pancreatic neoplasia. Also, our more recent data indicates that docosahexaenoic acid (DHA, omega-3 fatty acid) and linoleic acid (LA, omega-6 fatty acid) have opposing effects on protein kinase B (Akt)-mediated mitogenic signaling in Human Pancreatic Duct Epithelial cells in vitro. Furthermore, published studies suggest that one mechanism of action may be through cyclooxygenase (COX)-2 derived prostaglandin E2 (PGE2) secretion leading to cell proliferation. In our current work, we demonstrate that DHA treated HPDE cells do not generate a change in phosphorylated Akt (pAkt) levels and proliferation between cells with or without COX-2 inhibition. As a major maker of proliferation, Akt is often activated by phosphatidylinositol 3 kinase (PI3K), which facilitates conversion of phosphatidylinositol bisphosphate (PIP2) to phosphatidylinositol trisphosphate (PIP3), and PIP3 phosphorylates Akt. Yet the effects of DHA are not directly at the level of PI3K, as HPDE cells treated with a PI3K inhibitor (LY294002), a significantly further reduction in DHA-induced decrease of pAkt. Therefore, it is likely that DHA may not mediate pAkt through PI3K, and we propose that due to its high lipid solubility, DHA may interact with membrane-tethered targets including PIP2.

Citation Format: Lingji Zhu, Windel Emman T. Marsacarinas, Daniel R. Principe, Paul J. Grippo. Omega-3 fatty acids may regulate levels of pAkt through a mechanism independent of PI3K. [abstract]. In: Proceedings of the Twelfth Annual AACR International Conference on Frontiers in Cancer Prevention Research; 2013 Oct 27-30; National Harbor, MD. Philadelphia (PA): AACR; Can Prev Res 2013;6(11 Suppl): Abstract nr A31.
Abstract A33: The novel ways to inhibit atrophy of thymus and reconstructing the immune function in preventing the advance of tumor
Authors: Xu Jie , Xu Ze , Tovanich Sitthipol , Wu Bin
Published: May 2019

Objective: The objective of this research was to search the new ways to reconstruct the immune function.

Methods: 200 Kunming mice, 5 to 6 weeks old, divided into 8 Groups: control group bearing tumors (Group B, n=9);observation group for combined transplantation of fetal liver, spleen and thymus cells(Group CI, n=15); observation group(Group CII, n=15; carry on combined transplantation to this group once a week for successive 5 weeks and then execute the mice);treatment group with transplantation of fetal liver cells (Group F);treatment group with transplantation of fetal spleen cells (Group G); treatment group with transplantation of fetal thymus cells (Group H); treatment group with combined transplantation of fetal liver and spleen cells (Group I);treatment group with combined transplantation of fetal liver and thymus cells (Group K), nF=nG=nH=nI=nJ=nK= 12. First, prepare mice of ascitic type after the anabiosis of the root of Ehrlich ascites tumor; when the ascites are formed, draw out the ascites of the cancer cells and collect them to inoculate the experimental mice under the skin of the right hollow viscera to make the subcutaneous solid tumor model bearing Ehrlich Ascites tumor. When the model is prepared, carry out correspondent cell transplantation once a week for each group. After prepared of the suspension of fetal liver, spleen and thymus, they were transplanted into above animal models to record the tumor growth, disappear, survival time, the immune function and the tissue pathology change and compared each experimental group number.

Results: The results showed that in three experimental groups the rate which the tumors were completely disappeared is 40% in the early stages and the rate which the tumors were completely disappeared in the later stage is 46.67%. After the tumors completely disappeared, the animals can survive for a long time. The partial disappeared rate is 26.67% in the early group and is 13.33% in the long-term group. In the partial group the average survival time is above one month which the immune function increase and immune organ enlarge. The immune organ histology slides showed that the organ cells proliferation increased.

Conclusion: Reconstitution of immune system organ completely and partially can help the host to fight the tumor and to improve the treatment effects.

Citation Format: Jie Xu, Ze Xu, Sitthipol Tovanich, Bin Wu. The novel ways to inhibit atrophy of thymus and reconstructing the immune function in preventing the advance of tumor. [abstract]. In: Proceedings of the Twelfth Annual AACR International Conference on Frontiers in Cancer Prevention Research; 2013 Oct 27-30; National Harbor, MD. Philadelphia (PA): AACR; Can Prev Res 2013;6(11 Suppl): Abstract nr A33.
Abstract A48: Sedentary behavior is associated with colorectal adenoma recurrence in men
Authors: Sardo Christine L. , Ashbeck Erin L. , Hibler Elizabeth A. , Roe Denise , Harris Robin B. , Cisneroz Martin , Lance Peter , Martinez Maria Elena , Thomson Cynthia A. , Thompson Patricia A. , Jacobs Elizabeth T.
Published: May 2019

The association between physical activity and colorectal adenoma is equivocal. This study was designed to assess the relationship between various physical activity types and colorectal adenoma recurrence in a pooled sample of participants from the Wheat Bran Fiber and Ursodeoxycholic Acid phase III clinical trials with available data from the baseline Arizona Activity Frequency Questionnaire and a follow-up colonoscopy (n=1,730). Logistic regression modeling was used to estimate the relationship between sedentary, recreational, and household activity on colorectal adenoma recurrence overall and stratified by gender. No statistically significant associations were found between any activity type and colorectal adenoma recurrence overall however, males with the highest sedentary time demonstrated a statistically significant 45% higher odds of adenoma recurrence. Compared to the lowest quartile of sedentary time, the ORs (95% CIs) for the second, third, and fourth quartiles among men were 1.31 (0.93, 1.84), 1.47 (1.04, 2.09) and 1.45 (1.02, 2.06) respectively (P trend=0.03). In males, those with low recreational activity and high sedentary time was also associated with greater risk for recurrent adenoma, with an OR (95% CI) of 1.41(1.00-2.00) for high sedentary time/low recreational activity compared to the reference group (low sedentary time/low recreational activity). Our results suggests that sedentary time is associated with a higher risk of colorectal adenoma recurrence among men, supporting a role for sedentary lifestyle in the early stages of carcinogenesis. Efforts to intervene on sedentary time should be evaluated as a method for reducing recurrent adenomas.

Citation Format: Christine L. Sardo, Erin L. Ashbeck, Elizabeth A. Hibler, Denise Roe, Robin B. Harris, Martin Cisneroz, Peter Lance, Maria Elena Martinez, Cynthia A. Thomson, Patricia A. Thompson, Elizabeth T. Jacobs. Sedentary behavior is associated with colorectal adenoma recurrence in men. [abstract]. In: Proceedings of the Twelfth Annual AACR International Conference on Frontiers in Cancer Prevention Research; 2013 Oct 27-30; National Harbor, MD. Philadelphia (PA): AACR; Can Prev Res 2013;6(11 Suppl): Abstract nr A48.
Abstract A58: Serum transforming growth factor-β1 and risk of pancreatic cancer in three prospective cohort studies
Authors: Jacobs Eric J. , Newton Christina C. , Silverman Debra , Nogueira Leticia , Albanes Demetrius , Månnistö Satu , Stolzenberg-Solomon Rachael Z.
Published: May 2019

Background: Clinically evident chronic pancreatitis is an established, strong risk factor for pancreatic cancer. A small Japanese cohort study reported that pre-diagnostic serum transforming growth factor-β1 (TGF-β1) concentration, a potential marker of subclinical pancreatic inflammation, was associated with higher risk of pancreatic cancer.

Methods: Serum TGF-β1 concentrations were measured in pre-diagnostic samples drawn from 729 pancreatic cancer cases and 907 matched controls from a cohort of Finnish male smokers (the Alpha-Tocopherol, Beta-Carotene (ATBC) Cancer Prevention Study) and two cohorts of U.S. men and women, the Cancer Prevention Study-II (CPS-II) and the Prostate, Lung, Colorectal and Ovarian (PLCO) Cancer Screening Trial. Multivariable-adjusted odds ratios (ORs) were estimated using conditional logistic regression.

Results: Overall, high serum TGF-β1 concentration was associated with a marginally statistically significant increase in risk of pancreatic cancer (OR = 1.36, 95% confidence interval (CI), 0.98-1.88 for highest vs. lowest quintile). This association differed significantly by follow-up time (p = 0.02). Serum TGF-β1 concentration was not associated with risk during the first 10 years of follow-up, but was associated with risk during follow-up after 10 years (OR = 2.13, 95% CI 1.23-3.68 for highest vs. lowest quintile).

Conclusions: These results suggest that high serum TGF-β1 may be associated with increased risk of pancreatic cancer after a latency period of several years. Further research examining the magnitude and timing of associations between serum TGF-β1 and other potential markers of pancreatic inflammation may be useful in clarifying the role of inflammation in pancreatic carcinogenesis.

Citation Format: Eric J. Jacobs, Christina C. Newton, Debra Silverman, Leticia Nogueira, Demetrius Albanes, Satu Månnistö, Rachael Z. Stolzenberg-Solomon. Serum transforming growth factor-β1 and risk of pancreatic cancer in three prospective cohort studies. [abstract]. In: Proceedings of the Twelfth Annual AACR International Conference on Frontiers in Cancer Prevention Research; 2013 Oct 27-30; National Harbor, MD. Philadelphia (PA): AACR; Can Prev Res 2013;6(11 Suppl): Abstract nr A58.