Control Disease Progression Research Articles

Abstract 1223: Somatic mutations in collagens impact patient outcomes in cancer

Abstract Stomach cancer remains among the most lethal diseases around the world demanding improved treatments. The tumor microenvironment (TME) is a critical driver of tumor progression and response to therapy and mediates many of the cancer hallmarks. Collagens are major components of the TME that controls disease progression and mediate therapeutic response. Collagens have been associated with stiffening of the tumor stroma, malignancy and therapeutic resistance. Collagenopathies are caused by loss of function collagen mutations that disrupt tissue formation and are dominant negative variants. We have found somatic tumor variants in collagens that are similar loss-of-function mutations as the germline variants observed in collagenopathies, providing guidance to interpret these cancer mutations. Indeed, the role of somatic mutations in collagens has not been addressed. Remarkably, we found multiple independent lines of evidence that collagen variants impact stomach adenocarcinoma tumors, consistent with a model that collagen variants disrupt the extracellular matrix (ECM) leading to improved therapeutic responses. 1) We find that loss-of-function collagen missense and nonsense mutations are associated with improved survival and disease-free progression times in gastric tumors in the TCGA dataset. 2) The same type of mutations observed in cancer are known to cause rare human diseases and therefore have the potential to impact cell function. 3) Independent of the patient outcome data, collagen variants were associated with significant changes in expression of tumor environment factors including ECM glycoproteins and EMT expression signatures. 4) Remapping RNA-seq reads reveals that single nucleotide variants of the collagens, matching the exome sequencing data are expressed. We will present computational and functional data supporting the hypothesis that somatic variants impact gastric tumors as well as analysis of the impact of collagens somatic mutations PanCancer. Somatic mutations in collagens represent a new paradigm for how cancer cells mediate the TME providing new biomarker and therapeutic opportunities to disrupt the ECM and improve outcomes for cancer patients. Citation Format: Alexander S. Brodsky, Jay Khurana, Dongfang Yang, Ece Gamsiz, Ian Wong, Murray Resnick. Somatic mutations in collagens impact patient outcomes in cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 1223.

Abstract 1025: Mechanism of antitumor effect of Sorafenib in anaplastic thyroid cancer cell lines

Abstract Introduction: Anaplastic thyroid cancer (ATC) is a rare refractory disease, found in 1-3% of thyroid cancer. Because of its highly malignant potential, patients often become lethal within 6 months, nevertheless for intensive multimodal therapies. Recent observations indicated the strong efficacy of multi-kinase inhibitor to control disease progression of ATC. Frequent BRAF mutation (40-60%) in tumors of ATC was reported in Japan, indicating BRAF gene alteration as possible molecular target. Moreover, the secretions of VEGF were often found in ATC cell lines, suggesting the important role of VEGF-mediated tumor neo-vascularization in the aggressive progression of ATC. We, thus, examined the antitumor effect of Sorafenib, a multi-kinase inhibitor demonstrating its effect by inhibiting both BRAF and VEGF signal. Materials & Methods: Human ATC cell lines having four different gene mutations were used (OCUT-4; BRAF mutation, OCUT-6, ACT-1; NRAS mutation, OCUT-2; BRAS and PI3KCA mutation). The effect of Sorafenib on cellular viability was evaluated by MTT assay. In order to investigate the mechanism of cellular damage by Sorafenib, cell cycle was evaluated by flowcytometry, and the signal transduction of RAF/MEK pathway was examined by Western blotting. The amount of VEGF secretion from cells was measured by ELISA. Expression of VEGF-receptor in cells was evaluated by Western blotting. Furthermore, the effects of Sorafenib on human vascular endothelial cells were investigated by recruiting HUVEC (Kurabo, Japan) stimulated with VEGF and conditioned medium of the cancer cells. Results: The effect of Sorafenib appears most strongly in OCUT-4 cell with BRAF mutation compared with other cell lines. However, the impairment of cellular viability was shown at relatively high concentration (>100 nM). OCUT-4 showed G1 phase arrest by Sorafenib exposure. The specific effect of BRAF inhibition was confirmed by the suppression of MEK and ERK phosphorylation in OCUT-4. The suppression was not observed in OCUT-6, a cell line with NRAS mutation. The paradoxical increase of MEK phosphorylation was found in this cell line, instead. Every cell line secreted different amount of VEGF, and the proliferation of HUVEC was stimulated by their conditioned mediums similarly as by VEGF. The stimulation of proliferation was suppressed both by anti-VEGF antibody and Sorafenib. Discussion: In the present study, we clearly demonstrated that Sorafenib inhibits growth of human vascular endothelium mediated by VEGF secretion from cancer cells, as well as direct cell cycle arrest on ATC cells. A high concentration of Sorafenib may be needed to show inhibition on the RAF/MEK pathway. Furthermore, the inhibition of the pathway was not effective when additional growth stimulatory pathway than RAF was activated as in case of OCUT-2, or RAS gene were mutated. However, in any case, cancer cell growth mediated by autocrine system was inhibited clearly by Sorafenib. Citation Format: SAE ISHIHARA. Mechanism of antitumor effect of Sorafenib in anaplastic thyroid cancer cell lines [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 1025.

Histological improvement in chronic hepatitis B patients treated with bicyclol: real world experience

BackgroundBicyclol, the most commonly-used liver hepatoprotective drug in China, is often selected to control disease progression in CHB patients who refuse anti-viral treatment. However, data on histological changes after bicyclol treatment in these patients are scarce. Therefore, this study has been conducted to find out whether bicyclol has good benefits of histological improvement in CHB patients who refuse anti-viral agents.MethodsThe demographic, clinical and pathological data were collected from CHB patients who received bicyclol from January 2010 to June 2016. Improvement in liver inflammation or fibrosis is defined as at least one-grade or one-stage decrease as measured by the Scheuer scoring system. Thirty patients treated with ETV for 48 weeks were chosen as a control group to compare the histological improvement between bicyclol and entecavir (ETV) after 48-week treatment.ResultsA total of 123 patients with CHB treated with bicyclol were included in this study. Paired liver biopsies were performed in 70 patients. Inter-biopsy interval was 17.44 ± 8.90 months (12–60 months). As shown by facts, 41.4% patients achieved liver inflammation improvement, while only 10.0% patients showed liver inflammation progression after bicyclol treatment. In regarding to liver fibrosis, as shown by facts, 28.6% patients achieved fibrosis improvement. More importantly, It was found that the proportions of patients with liver inflammation and fibrosis improvement were both not significantly lower than those in ETV group (53.3% vs 63.3 and 36.7% vs 43.4%). Most of patients (82.4%) with elevated baseline ALT became normal after bicyclol treatment. More importantly, as shown by the multi-variate analysis, the treatment course of bicyclol was an independent factor for liver inflammation improvement. With the HBeAg status adjusted, ALT and HBV-DNA quantity, the odds ratio (95% confidence interval) of patients with ≥48-week treatment was 5.756 (1.893,17.500) when compared with patients via < 48-week treatment.ConclusionBicyclol can improve liver inflammation and the ALT normalization rate of CHB patients, especially when the treatment course is prolonged. This has confirmed that bicyclol could control hepatitis activity, which might be a good choice for CHB patients who refuse anti-viral treatments.

Multilevel Analysis of Factors Associated with Treatment-Seeking Behaviors among Caregivers with Febrile Children in Malawi.

Early diagnosis and treatment of childhood fever, an important sign of potentially serious infections such as malaria, is essential for controlling disease progression, and ultimately, preventing deaths. This study examined individual- and community-level factors associated with treatment-seeking behaviors and promptness in these behaviors among caregivers of febrile under-five children in Malawi. The 2015-2016 Malawi Demographic Health Survey was used to analyze a nationally representative sample of 4,133 under-five children who had fever within 2 weeks before the survey. A multilevel logistic regression model was used to examine the association between individual- and community-level factors and treatment-seeking behaviors. Approximately 67.3% of the caregivers reported seeking treatment for their febrile child, whereas only 46.3% reported promptly seeking treatment. Children from communities with moderate and high percentages of educated caregivers were more likely to be taken for treatment (adjusted odds ratio [aOR] = 1.26, 95% CI = 1.01-1.58 and aOR = 1.31, 95% CI = 1.02-1.70, respectively) than those from communities with a low percentage of educated caregivers. Children from communities with moderate and high percentages of caregivers complaining about the distance to a health facility were less likely to be taken for treatment (aOR = 0.74, 95% CI = 0.58-0.96 and aOR = 0.67, 95% CI = 0.51-0.88, respectively). At the individual level, having a cough in the last 2 weeks, region, religion, and having better health behaviors in other health dimensions were associated with fever treatment-seeking behaviors among Malawian caregivers. Programs aimed at improving treatment-seeking behaviors should consider these factors and the regional variations observed in this study.

Actin Cytoskeleton Straddling the Immunological Synapse between Cytotoxic Lymphocytes and Cancer Cells.

The immune system is a fundamental part of the tumor microenvironment. In particular, cytotoxic lymphocytes, such as cytolytic T cells and natural killer cells, control tumor growth and disease progression by interacting and eliminating tumor cells. The actin cytoskeleton of cytotoxic lymphocytes engaged in an immunological synapse has received considerable research attention. It has been recognized as a central mediator of the formation and maturation of the immunological synapse, and its signaling and cytolytic activities. In comparison, fewer studies have explored the organization and function of actin filaments on the target cancer cell side of the immunological synapse. However, there is growing evidence that the actin cytoskeleton of cancer cells also undergoes extensive remodeling upon cytotoxic lymphocyte attack, and that such remodeling can alter physical and functional interactions at the immunological synapse. In this article, we review the current knowledge of actin organization and functions at both sides of the immunological synapse between cytotoxic lymphocytes and cancer cells, with particular focus on synapse formation, signaling and cytolytic activity, and immune evasion.

7-Pyrrolidinethoxy-4'-Methoxyisoflavone Prevents Amyloid β-Induced Injury by Regulating Histamine H3 Receptor-Mediated cAMP/CREB and AKT/GSK3β Pathways.

In studies on the treatment of Alzheimer’s disease (AD), in which cognition is enhanced even modestly or selectively, it has been considered that the histamine H3 receptor (H3R) may be a potential target. In this study, we aimed at evaluating the ability of 7-pyrrolidinethoxy-4′-methoxyisoflavone (indicated as LC1405), a novel potential H3R antagonist identified from our H3R antagonist screening system, to ameliorate amyloid β (Aβ)-induced cognitive deficits, and to explore the underlying mechanisms that are related to H3R-modulated signaling. Our results demonstrated that LC1405 effectively reduced the progression of Aβ-associated disorders, such as improved learning and memory capabilities, preserved tissues from suffering neurodegeneration and ultrastructural abnormalities, and ameliorated cholinergic dysfunction in an APP/PS1 double transgenic mouse model of AD. In an in vitro model, LC1405 protected neuronal cells against copper-induced Aβ toxicity, as demonstrated by the improvement in cell viability and decrease in neuronal apoptotic ratio. In addition, treatment with LC1405 resulted in the up-regulation of acetylcholine (ACh) or histamine release and provided neuroprotection through cellular signaling cascades involving H3R-mediated cAMP/CREB and AKT/GSK3β pathways. Furthermore, the beneficial effects of LC1405 on Aβ-mediated toxicity and H3R-mediated cAMP/CREB and AKT/GSK3β axes were reversed after pharmacological activation of H3R. In conclusion, our results demonstrated that LC1405 blocked Aβ-induced toxicity through H3R-modulated signaling transduction both in vitro and in vivo. The results also suggested that LC1405 might have translational potential as a complementary therapy to control disease progression in AD patients who developed cognitive deficits with H3R-related ACh neurotransmission abnormality.

Abstract OT2-05-02: International retrospective cohort study of locoregional and systemic therapy in oligometastatic breast cancer (OLIGO-BC1)

Abstract Breast cancer (BC) is so-called “systemic disease”, because disseminated cancer cells in bone marrow and blood are detected even in early BC patients. Despite adjuvant therapy and postoperative radiation therapy, patients with triple negative BC and Luminal B-like BC often relapse early and systemic therapy is the only way to control disease progression. On the other hand, some BC patients relapse several years later. In such patients, oligometastases are occasionally diagnosed, because metastatic cancer cells are slowly growing and indolent. Oligometastatic BC is defined as low volume metastatic disease with limited number and size of metastatic lesions (up to five and not necessarily in the same organ). This definition is proposed in the Advanced Breast Cancer guidelines that are developed as a joint effort from European School of Oncology and European Society of Medical Oncology. Several retrospective studies demonstrated survival benefit of locoregional therapy in addition to systemic therapy. Locoregional therapy consisted of surgical resection, radiation therapy, ablation therapy, etc. However, it remains unclear about survival benefit of combined therapy in oligometastatic BC. To improve the standard of cancer treatment through the cooperate studies on more effective therapeutic strategies based on drugs, surgery and/or radiotherapy, Federation of Asian Clinical Oncology (FACO) was established in 2012 by Chinese Society of Clinical Oncology (CSCO), Korean Society of Medical Oncology (KSMO) and Japan Society of Clinical Oncology (JSCO). Thus, FACO conducted a retrospective cohort study on oligometastatic BC. The primary endpoint is to compare the estimated 5-year overall survival (OS) of oligometastatic BC patients treated with combined therapy and systemic therapy alone. To hypothesize that combined therapy has more advantage of OS in oligometastatic BC, the 5-year OS rates are expected to be 50% and 40%, respectively. The estimated sample size is calculated to be the number of 698 cases (349 cases in each group) needed to prove the superiority of survival with a two-sided type I error rate of 5% and a statistical power of 80%. Case registry opened in February 2018 and will close in January 2019. We planned to register 700 cases, i.e., 234 cases each from investigators of CSCO, KSMO and JSCO. Update information will be discussed. Citation Format: Imoto S, Futamura M, Toi M, Fujiwara Y, Ueno T, Im Y-H, Im S-A, Ahn SG, Lee JE, Park YH, Wang K, Kitagawa Y, Nishiyama M. International retrospective cohort study of locoregional and systemic therapy in oligometastatic breast cancer (OLIGO-BC1) [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr OT2-05-02.

Disruption of Apicoplast Biogenesis by Chemical Stabilization of an Imported Protein Evades the Delayed-Death Phenotype in Malaria Parasites.

Malaria parasites (Plasmodium spp.) contain a nonphotosynthetic plastid organelle called the apicoplast, which houses essential metabolic pathways and is required throughout the parasite life cycle. The biogenesis pathways responsible for apicoplast growth, division, and inheritance are of key interest as potential drug targets. Unfortunately, several known apicoplast biogenesis inhibitors are of limited clinical utility because they cause a peculiar "delayed-death" phenotype in which parasites do not stop replicating until the second lytic cycle posttreatment. Identifying apicoplast biogenesis pathways that avoid the delayed-death phenomenon is a priority. Here, we generated parasites targeting a murine dihydrofolate reductase (mDHFR) domain, which can be conditionally stabilized with the compound WR99210, to the apicoplast. Surprisingly, chemical stabilization of this exogenous fusion protein disrupted parasite growth in an apicoplast-specific manner after a single lytic cycle. WR99210-treated parasites exhibited an apicoplast biogenesis defect beginning within the same lytic cycle as drug treatment, indicating that stabilized mDHFR perturbs a non-delayed-death biogenesis pathway. While the precise mechanism-of-action of the stabilized fusion is still unclear, we hypothesize that it inhibits apicoplast protein import by stalling within and blocking translocons in the apicoplast membranes.IMPORTANCE Malaria is a major cause of global childhood mortality. To sustain progress in disease control made in the last decade, new antimalarial therapies are needed to combat emerging drug resistance. Malaria parasites contain a relict chloroplast called the apicoplast, which harbors new targets for drug discovery. Unfortunately, some drugs targeting apicoplast pathways exhibit a delayed-death phenotype, which results in a slow onset-of-action that precludes their use as fast-acting, frontline therapies. Identification of druggable apicoplast biogenesis factors that will avoid the delayed-death phenotype is an important priority. Here, we find that chemical stabilization of an apicoplast-targeted mDHFR domain disrupts apicoplast biogenesis and inhibits parasite growth after a single lytic cycle, suggesting a non-delayed-death target. Our finding indicates that further interrogation of the mechanism-of-action of this exogenous fusion protein may reveal novel therapeutic avenues.

The role of microbiome in rheumatoid arthritis treatment

Rheumatoid arthritis (RA) is an autoimmune disorder with multifactorial etiology; both genetic and environmental factors are known to be involved in pathogenesis. Treatment with disease-modifying antirheumatic drugs (DMARDs) plays an essential role in controlling disease progression and symptoms. DMARDs have immunomodulatory properties and suppress immune response by interfering in various pro-inflammatory pathways. Recent evidence has shown that the gut microbiota directly and indirectly modulates the host immune system. RA has been associated with dysbiosis of the gut microbiota. Patients with RA treated with DMARDs show partial restoration of eubiotic gut microbiome. Hence, it is essential to understand the impact of DMARDs on the microbial composition and its consequent influences on the host immune system to identify novel therapies for RA. In this review, we discuss the importance of antirheumatic-drug-induced host microbiota modulations and possible probiotics that can generate eubiosis.

The Value of Imaging of the Parathyroid Glands in Secondary Hyperparathyroidism.

It is estimated that up to 90% of patients with chronic kidney disease develop secondary hyperparathyroidism (sHPT). Although the disease has multiple manifestations, the most important pathological feature, from the point of view of increased mortality, is represented by the ectopic arterial, myocardial and cardiac valvular calcifications. The calcifications are progressive and lead to high blood pressure, left ventricular hypertrophy, atrio-ventricular blocks, angina and myocardial infarction. Therefore the risk of cardio-vascular events is increased. Failure of drug therapy to control disease progression is an indication for parathyroidectomy. In sHPT all parathyroid glands are affected, hence the need to detect 4 glands intraoperatively, by bilateral cervical exploration. However, considering the possibility of ectopic localization of these glands as well as the possibility of some supernumerary glands, it is desirable to have an imagistic map as accurate as possible, thus avoiding the risk of postoperative recurrence. The available imaging investigations are represented by the ultrasound of the cervical region, the parathyroid scintigraphy and those of the second line - CT or MRI examination. If in primary hyperparathyroidism, where there is only one parathyroid adenoma (or two), the preoperative imaging results are satisfactory, in sHPT there are many cases in which the imaging does not reveal all four parathyroid glands.

Discovery of 4-oxoquinolines, a new chemical class of anti-HIV-1 compounds

Antiretroviral therapy (ART) against HIV-1 infection offers the promise of controlling disease progression and prolonging the survival of HIV-1-infected patients. However, even the most potent ART regimens available today cannot cure HIV-1. Because patients will be exposed to ART for many years, physicians and researchers must anticipate the emergence of drug-resistant HIV-1, potential adverse effects of the current drugs, and need for future drug development. In this study, we screened a small-molecule compound library using cell-based anti-HIV-1 assays and discovered a series of novel anti-HIV-1 compounds, 4-oxoquinolines. These compounds exhibited potent anti-HIV-1 activity (EC50 < 0.1 μM) with high selectivity indexes (CC50/EC50 > 2500) and favorable pharmacokinetic profiles in mice. Surprisingly, our novel compounds have a chemical backbone similar to the clinically used integrase (IN) strand transfer inhibitor (INSTI) elvitegravir, although they lack the crucial 3-carboxylate moiety needed for the common INSTI diketo motif. Indeed, the new 4-oxoquinoline derivatives have no detectable INSTI activity. In addition, various drug-resistant HIV-1 strains did not display cross resistance to these compounds. Interestingly, time-of-addition experiments indicated that the 4-oxoquinoline derivative remains its anti-HIV-1 activity even after the viral integration stage. Furthermore, the compounds significantly suppressed p24 antigen production in HIV-1 latently infected cells exposed with tumor necrosis factor alpha. These findings suggest that our 4-oxoquinoline derivatives with no 3-carboxylate moiety may become novel lead compounds in the development of anti-HIV-1 drugs.

Exercise Training in Cancer Control and Treatment.

Exercise training is playing an increasing role in cancer care, as accumulating evidence demonstrates that exercise may prevent cancer, control disease progression, interact with anti-cancer therapies, and improve physical functioning and psychosocial outcomes. In this overview article, we present the current state of the field of exercise oncology, which currently comprises of nearly 700 unique exercise intervention trials with more than 50,000 cancer patients. First, we summarize the range of these interventions with regard to diagnoses, clinical setting, timing, and type of intervention. Next, we provide a detailed discussion of the 292 trials, which have delivered structured exercise programs, outlining the impact of exercise training on cancer-specific, physiological, and psychosocial outcomes in the light of the challenges and physiological limitations cancer patients may experience. In summary, the safety and feasibility of exercise training is firmly established across the cancer continuum, and a wide range of beneficial effects on psychosocial and physiological outcomes are well documented. Many of these beneficial effects are linked to the general health-promoting properties of exercise. However, it is becoming increasing evident that exercise training can have direct effects on cancer and its treatment. This calls for future exercise oncology initiatives, which aim to target cancer-specific outcomes, and which are integrated into the concurrent cancer trajectory. Here, the field must bridge extensive knowledge of integrative exercise physiology with clinical oncology and cancer biology to provide a basis of individualized targeted approaches, which may place exercise training as an integrated component of standard cancer care. © 2019 American Physiological Society. Compr Physiol 9:165-205, 2019.

Development of a Novel Anti-CD19 Chimeric Antigen Receptor: A Paradigm for an Affordable CAR T Cell Production at Academic Institutions

Genetically modifying autologous T cells to express an anti-CD19 chimeric antigen receptor (CAR) has shown impressive response rates for the treatment of CD19+ B cell malignancies in several clinical trials (CTs). Making this treatment available to our patients prompted us to develop a novel CART19 based on our own anti-CD19 antibody (A3B1), followed by CD8 hinge and transmembrane region, 4-1BB- and CD3z-signaling domains. We show that A3B1 CAR T cells are highly cytotoxic and specific against CD19+ cells in vitro, inducing secretion of pro-inflammatory cytokines and CAR T cell proliferation. In vivo, A3B1 CAR T cells are able to fully control disease progression in an NOD.Cg-PrkdcscidIl2rdtm1Wjl/SzJ (NSG) xenograph B-ALL mouse model. Based on the pre-clinical data, we conclude that our CART19 is clearly functional against CD19+ cells, to a level similar to other CAR19s currently being used in the clinic. Concurrently, we describe the implementation of our CAR T cell production system, using lentiviral vector and CliniMACS Prodigy, within a medium-sized academic institution. The results of the validation phase show our system is robust and reproducible, while maintaining a low cost that is affordable for academic institutions. Our model can serve as a paradigm for similar institutions, and it may help to make CAR T cell treatment available to all patients.

Blastic plasmacytoid dendritic cell neoplasm: genomics mark epigenetic dysregulation as a primary therapeutic target.

Blastic plasmacytoid dendritic cell neoplasm (BPDCN) is a rare and aggressive hematologic malignancy for which there is still no effective therapy. In order to identify genetic alterations useful for a new treatment design, we used whole-exome sequencing to analyze 14 BPDCN patients and the patient-derived CAL-1 cell line. The functional enrichment analysis of mutational data reported the epigenetic regulatory program to be the most significantly undermined (P<0.0001). In particular, twenty-five epigenetic modifiers were found mutated (e.g. ASXL1, TET2, SUZ12, ARID1A, PHF2, CHD8); ASXL1 was the most frequently affected (28.6% of cases). To evaluate the impact of the identified epigenetic mutations at the gene-expression and Histone H3 lysine 27 trimethylation/acetylation levels, we performed additional RNA and pathology tissue-chromatin immunoprecipitation sequencing experiments. The patients displayed enrichment in gene signatures regulated by methylation and modifiable by decitabine administration, shared common H3K27-acetylated regions, and had a set of cell-cycle genes aberrantly up-regulated and marked by promoter acetylation. Collectively, the integration of sequencing data showed the potential of a therapy based on epigenetic agents. Through the adoption of a preclinical BPDCN mouse model, established by CAL-1 cell line xenografting, we demonstrated the efficacy of the combination of the epigenetic drugs 5’-azacytidine and decitabine in controlling disease progression in vivo.

S100 proteins as therapeutic targets.

The human genome codes for 21 S100 protein family members, which exhibit cell- and tissue-specific expression patterns. Despite sharing a high degree of sequence and structural similarity, the S100 proteins bind a diverse range of protein targets and contribute to a broad array of intracellular and extracellular functions. Consequently, the S100 proteins regulate multiple cellular processes such as proliferation, migration and/or invasion, and differentiation, and play important roles in a variety of cancers, autoimmune diseases, and chronic inflammatory disorders. This review focuses on the development of S100 neutralizing antibodies and small molecule inhibitors and their potential therapeutic use in controlling disease progression and severity.

Systemic Therapy for Combined Hepatocellular-Cholangiocarcinoma: A Single-Institution Experience.

Background: Combined hepatocellular-cholangiocarcinoma tumors (cHCC-CCA) are a heterogeneous group of rare malignancies that have no established optimal treatment. Patients and Methods: We identified patients with cHCC-CCA treated at a tertiary center and retrospectively examined their histology, interventions, and outcomes. We calculated disease control rate (DCR), disease progression, overall survival, and progression-free survival (PFS) between treatment subgroups. Results: A total of 123 patients were evaluable. Interventions included resection, locoregional therapy, transplant, chemotherapy, and targeted agents. Ultimately, 68 patients received systemic treatment-57 with gemcitabine plus either 5-fluoropyrimidine (5-FU) or a platinum combination. Disease progression was more common in the gemcitabine/5-FU group versus gemcitabine/platinum (P=.028), whereas DCR favored gemcitabine/platinum (78.4% vs 38.5%; P=.0143). Median PFS from time of initial diagnosis favored the gemcitabine/platinum group, but the difference did not reach statistical significance. Targeted agents had minimal to no effect on survival metrics. Conclusions: Gemcitabine/platinum seems to be a superior regimen for patients with cHCC-CCA who require systemic treatment. Further studies are needed to clarify the regimen's efficacy and applicability in patient subgroups.

Cancer biomarkers in biosensors fabrication for diagnostic purposes

Cancer is one of the leading causes of death worldwide and the number of deaths is increasing due to the limitations of the available diagnostic tests. Early diagnosis plays an important role in controlling disease progression and response to therapy. Hence, cancer biomarkers are widely exploited in oncology to detect the presence of tumors and to evaluate the subsequent treatment of patients. Biomarker-based biosensors have attracted attention due to their simplicity, rapidity, selectivity and sensitivity. The main obstacle that prevents the development of biosensors is the fact that cancer is a complex set of diseases and only a few biomarkers are exploited by oncologists to detect cancer. This talk will be focusing on the fabrication of biosensors for cancer biomarker detection and highlights various biomarker detection techniques. It will also discuss the limitations associated with some developed systems for immunoassay technology.

Efficacy and feasibility of combining FOLFIRINOX and stereotactic radiotherapy for patients with LAPC (LAPC-1 Trial)

Introduction: Patients with locally advanced pancreatic cancer (LAPC) rarely undergo resection with curative intent and controlling disease progression should be the goal of the treatment. We conducted a multicenter phase II trial (ClinicalTrials.gov Identifier: NCT02292745) to investigate the efficacy and feasibility of combining FOLFIRINOX and Stereotactic Radiotherapy (SBRT) for patients with LAPC (LAPC-1 trial). Methods: All eligible patients with biopsy-proven LAPC were included between January 2015 and June 2017. These patients underwent a staging laparoscopy to exclude occult metastasis and were treated with FOLFIRINOX (8 cycles) followed by SBRT (5 fractions/8 Gy) if there was no tumor progression on imaging. Primary outcome was overall survival (OS). Secondary outcomes were progression free survival (PFS), treatment-related toxicity, and resection rates. Results: In total, 53 patients were included in the study. The preliminary survival data showed a median OS of 18 months (95% CI 16-19) and median PFS of 12 months (95% CI 11-13). Thirty (60%) events of a grade 3 or 4 adverse event occurred during FOLFIRINOX. Thirty-nine (74%) patients had no tumor progression after the chemotherapy andreceived the full dose of SBRT. One (3%) patient had a grade 5 adverse event three months after SBRT, while no grade 3 or 4 adverse event occurred after SBRT. Seven (14%) patients underwent a resection, all being a radical resection. Conclusion: FOLFIRINOX combined with SBRT in patients with inoperable LAPC is feasible and effecitve. Forteen percent of the patients became operable and 6% had a complete response.

Abstract A50: Trivalent CAR T cells mitigate CD19-negative relapse and improve tumor control in primary pre-B cell acute lymphoblastic leukemia (B-ALL)

Abstract B-acute lymphoblastic leukemia (B-ALL) is the most common malignancy in children, and limited treatment options exist for patients with relapsed or refractory disease. Cellular immunotherapy, specifically chimeric antigen receptor (CAR) T cells targeting CD19 have demonstrated remarkable efficacy in treating B-ALL. However, recent reports show that up to 40% of patients who relapse after CD19 CAR T cell therapy have CD19-negative disease, justifying a need to expand CAR T cell therapy for B-ALL to include additional tumor-associated antigens (TAAs). Here, we hypothesize that targeting three distinct leukemia antigens CD19, CD20, and CD22 will improve B-ALL therapy outcomes and control disease progression during CD19-negative relapse. We designed two trivalent CAR T cell products with exodomains derived from single chain variable fragments (ScFv) targeting CD19 (FMC63 ScFv), CD20 (Rituximab ScFv), and CD22 (m971 ScFv) fused to the intracellular signaling domains of the co-stimulatory molecule 4-1BB and the T-cell receptor zeta chain (2nd generation). Using viral 2A intervening sequences for near equal expression, the first T cell product expresses the three CARs individually on the surface of a single T cell (TriCAR). The second T cell product expresses a traditional single CAR targeting CD19 and a second bi-specific CAR targeting CD20 and CD22 through a tandem arrangement (SideCAR). Donor T cells were successfully engineered to express the CARs using a retroviral system and the surface expression of these CAR molecules was confirmed by flow cytometry. Using a target expression validated panel of patient derived B-ALL cells (US7 CD19/CD20/CD22 +++/++/++, LAX-56 +++/+/+, TXL-2 +++/++/+++), we observed that TriCAR and SideCAR T cells killed ALL cells more robustly than CD19 CAR T cells at low effector to target ratios (E:T) in a 51Cr release cytotoxicity assay. TriCAR and SideCAR T cells secreted similar levels of IFN-gamma; when compared to CD19 CAR T cells demonstrating a safety profile very similar to the CD19 CAR T cells, but with enhanced killing. Further, we tested the efficacy of TriCAR and SideCAR T cells against primary CD19-negative relapsed bone marrow samples and CRISPR CD19 knockouts of the three primary ALL samples. Using these models of CD19 escape we demonstrated that trivalent CAR T cells effectively mitigated CD19 negative relapse, producing IFN-gamma; and killing CD19-negative primary ALL, while CD19 CAR T cells remained ineffective. In conclusion, trivalent CAR T cells are effective at targeting primary ALL cells of varying antigen profiles and mitigating CD19 negative relapse. This strategy has potential for use as a front-line therapy for primary ALL as well as a salvage therapy for patients with CD19-negative disease relapse. Citation Format: Kristen Fousek, Junji Watanabe, Xingyue An, Ann George, Heba Samaha, Shoba Navai, Tiara T. Byrd, Jonathan Kirzner, Hye Na Kim, Albert Jang, Sujith Joseph, Matthew Baker, Meenakshi Hegde, Navin Varadarajan, Nora Heisterkamp, Hisham Abdel-Azim, Nabil Ahmed. Trivalent CAR T cells mitigate CD19-negative relapse and improve tumor control in primary pre-B cell acute lymphoblastic leukemia (B-ALL) [abstract]. In: Proceedings of the AACR Special Conference on Tumor Immunology and Immunotherapy; 2017 Oct 1-4; Boston, MA. Philadelphia (PA): AACR; Cancer Immunol Res 2018;6(9 Suppl):Abstract nr A50.

Abstract A81: Early TLR-mediated killing of leukemia in bone marrow is correlated with durable protection against B cell precursor acute lymphoblastic leukemia

Abstract The ability of Toll-like receptor (TLR)-induced innate immune responses to activate adaptive immune responses offers considerable therapeutic potential for cancer treatment, most likely as part of combination therapies. The potent immunostimulatory capacity of TLR agonists provides means to generate antigen-specific antitumor T cell responses from antigen-nonspecific innate immune stimulation. B cell precursor (BCP) acute lymphoblastic leukemia (ALL) exhibits the very low mutational burden common to other pediatric cancers. Despite this limited neo-antigenicity, we previously reported the ability of CpG oligodioxynucleotides (ODN), a ligand for TLR9, to mediate anti-leukemia activities that establish long-term protection against ALL outgrowth in a transplantable syngeneic model using cell lines. CpG ODN also reduced the burden of primary human ALL in mouse xenografts, primarily via induction of NK cell-mediated cytotoxicity. However, our recent demonstration that endosomal TLR agonists generated distinct effects on pre-leukemic BCP cells, coupled with the divergent effects of TLR ligands on the immunogenicity of primary human ALL cells suggest that there are significant variables that contribute to the overall outcome of TLR stimulation in the context of BCP cell malignancy. In this study, we compared the ligands for TLR3 (polyI:C), TLR7/8(R848) and TLR9 (CpG ODN) for their ability to elicit control of primary ALL cells and correlated protection with early innate immune activation to identify the necessary component of a long-term protective anti-leukemic response. We adoptively transferred syngeneic primary ALL cells to wild-type mice then administered TLR ligands starting at day 7 for 3 doses every 4 days. 21 days after leukemia challenge, we evaluated the disease burden in the peripheral blood, spleen, and bone marrow of recipients. While a significantly lower disease burden was observed in all three anatomical compartments of mice treated with polyI:C, CpG ODN- and R848-treated mice failed to control the early outgrowth of transferred cells in the spleen and bone marrow, respectively. While R848-treated mice had a slightly delayed disease progression with median survival (MS) of 40 days compared to that of 28 days of PBS-treated control group, CpG ODN treatment conferred a significant survival advantage where over 57% of treated mice achieved a prolonged disease-free status. Despite successfully inducing systemic anti-ALL responses, poly I:C treatment failed to confer durable protection, achieving only a modest increase in disease-free survival in treated mice (MS=42 days). Moreover, CpG ODN-induced long-term survival in the absence of effective early immune-mediated control of ALL in spleen implies that bone marrow is not only an important homing niche supporting the survival and proliferation of leukemia blasts prior to migration into the circulation, but a critical target site for controlling disease progression. Furthermore, to investigate the early innate immune responses associated with the differential overall effects induced by TLR agonists, we evaluated the activation status of innate immune system using RAG-knockout mice. A single administration of CpG ODN, but not polyI:C nor R848, was sufficient to rapidly induce anti-ALL immune responses involving activated natural killer and antigen-presenting cells in the bone marrow of the mice bearing ALL in 4 days. This suggests that CpG ODN has superior capacity to initiate innate immune-mediated anti-ALL immune responses and activate subsequent antigen-specific T cell responses. TLR-mediate innate immune responses induced early in life are distinct from that induced in adult life. Given the peak incidence of pediatric ALL between 3-5 years of age, we are currently examining the influence of age on the TLR-induced anti-ALL immune responses to further evaluate the therapeutic benefits of TLR ligands. Our results demonstrate the differential magnitude of tissue-specific innate immune-mediated control of leukemia outgrowth induced by TLR stimulations correlating with durable disease-free survival. These findings provide mechanistic explanation for TLR-mediated protective immune responses and highlight the potential target site necessary for effective elimination of leukemia cells. Citation Format: Sumin Jo, Peter van den Elzen, Gregor S.D Reid. Early TLR-mediated killing of leukemia in bone marrow is correlated with durable protection against B cell precursor acute lymphoblastic leukemia [abstract]. In: Proceedings of the AACR Special Conference on Tumor Immunology and Immunotherapy; 2017 Oct 1-4; Boston, MA. Philadelphia (PA): AACR; Cancer Immunol Res 2018;6(9 Suppl):Abstract nr A81.