Development of resistance to FAK inhibition in pancreatic cancer is linked to stromal depletion

OBJECTIVE

We investigated how pancreatic cancer developed resistance to focal adhesion kinase (FAK) inhibition over time.

DESIGN

Pancreatic ductal adenocarcinoma (PDAC) tumours from KPC mice (p48-CRE; LSL-KRas^G12D/wt; p53^flox/wt) treated with FAK inhibitor were analysed for the activation of a compensatory survival pathway in resistant tumours. We identified pathways involved in the regulation of signal transducer and activator of transcription 3 (STAT3) signalling on FAK inhibition by gene set enrichment analysis and verified these outcomes by RNA interference studies. We also tested combinatorial approaches targeting FAK and STAT3 in syngeneic transplantable mouse models of PDAC and KPC mice.

RESULTS

In KPC mice, the expression levels of phosphorylated STAT3 (pSTAT3) were increased in PDAC cells as they progressed on FAK inhibitor therapy. This progression corresponded to decreased collagen density, lowered numbers of SMA⁺ fibroblasts and downregulation of the transforming growth factor beta (TGF-β)/SMAD signalling pathway in FAK inhibitor-treated PDAC tumours. Furthermore, TGF-β production by fibroblasts in vitro drives repression of STAT3 signalling and enhanced responsiveness to FAK inhibitor therapy. Knockdown of SMAD3 in pancreatic cancer cells abolished the inhibitory effects of TGF-β on pSTAT3. We further found that tumour-intrinsic STAT3 regulates the durability of the antiproliferative activity of FAK inhibitor, and combinatorial targeting of FAK and Janus kinase/STAT3 act synergistically to suppress pancreatic cancer progression in mouse models.

CONCLUSION

Stromal depletion by FAK inhibitor therapy leads to eventual treatment resistance through the activation of STAT3 signalling. These data suggest that, similar to tumour-targeted therapies, resistance mechanisms to therapies targeting stromal desmoplasia may be critical to treatment durability.

IRAK4 mediates colitis-induced tumorigenesis and chemoresistance in colorectal cancer

Aberrant activation of the NF-κB transcription factors underlies chemoresistance in various cancer types, including colorectal cancer (CRC). Targeting the activating mechanisms, particularly with inhibitors to the upstream IκB kinase (IKK) complex, is a promising strategy to augment the effect of chemotherapy. However, clinical success has been limited, largely because of low specificity and toxicities of tested compounds. In solid cancers, the IKKs are driven predominantly by the Toll-like receptor (TLR)/IL-1 receptor family members, which signal through the IL-1 receptor-associated kinases (IRAKs), with isoform 4 (IRAK4) being the most critical. The pathogenic role and therapeutic value of IRAK4 in CRC have not been investigated. We found that IRAK4 inhibition significantly abrogates colitis-induced neoplasm in APCMin/+ mice, and bone marrow transplant experiments showed an essential role of IRAK4 in immune cells during neoplastic progression. Chemotherapy significantly enhances IRAK4 and NF-κB activity in CRC cells through upregulating TLR9 expression, which can in turn be suppressed by IRAK4 and IKK inhibitors, suggesting a feed-forward pathway that protects CRC cells from chemotherapy. Lastly, increased tumor phospho-IRAK4 staining or IRAK4 mRNA expression is associated with significantly worse survival in CRC patients. Our results support targeting IRAK4 to improve the effects of chemotherapy and outcomes in CRC.

Prevalence and characteristics of e-cigarette users among Malaysian current and ex-smokers

INTRODUCTION

Electronic cigarettes (ECs) are new devices that have been accepted widely by both smokers and non-smokers. However, the evidence on EC used in Malaysia is scarce. The objective of this study was to determine the prevalence of EC use and the socio-demographic and smoking characteristics associated with current EC use among Malaysian current and ex-smokers.

METHODS

This was a sub-analysis of data from a cross-sectional, national-population- based EC study conducted from May to June in 2016 in Malaysia. A detailed description of the sampling methods can be found in the National E-cigarette Survey (NECS) 2016 report. Briefly, data were obtained from 1396 individuals who had ever been smokers, i.e., 957 (68.6%) current smokers and 439 (31.4%) ex-smokers.

RESULTS

Current EC use was found predominantly among current smokers (8.0%) as compared with ex-smokers (4.3%). Among current smokers, the main reasons given for smoking ECs were wanting to try it (44.7%), followed by intention to quit tobacco smoking (15.8%) and to reduce tobacco smoking (10.5%). Using multiple logistic regression analysis, we found that among current smokers, current EC users were more likely to be younger, i.e., 18-44 years (aOR= 4.83, 95% CI= 1.97-11.86, p=0.001), urban residents (aOR= 1.89, 95% CI= 1.15-3.11, p=0.012), single/ divorced/ widowed (aOR= 2.11, 95% CI= 1.24-3.61, p=0.006) and students (aOR= 2.25, 95% CI= 1.01-5.01, p=0.048). Among exsmokers, only younger respondents (18-44 years old) was reported as being more likely to be current EC users (aOR= 3.81, 95% CI= 1.14-12.76, p=0.030).

CONCLUSION

This study showed that currently using and ever having used ECs were more prevalent among current smokers. The reasons given for initiating EC use among current smokers were mainly wanting to try it, followed by intention to quit and to reduce tobacco smoking. Current EC use appears to be common among current smokers who are younger, urban residents, single/divorced/widowed and students. Therefore, EC cessation intervention strategies and policies should target these high-prevalence groups.

Folate Receptor α-Targeted 89Zr-M9346A Immuno-PET for Image-Guided Intervention with Mirvetuximab Soravtansine in Triple-Negative Breast Cancer

Folate receptor α (FRα) is a well-studied tumor biomarker highly expressed in many epithelial tumors such as breast, ovarian, and lung cancers. Mirvetuximab soravtansine (IMGN853) is the antibody-drug conjugate of FRα-binding humanized monoclonal antibody M9346A and cytotoxic maytansinoid drug DM4. IMGN853 is currently being evaluated in multiple clinical trials, in which the immunohistochemical evaluation of an archival tumor or biopsy specimen is used for patient screening. However, limited tissue collection may lead to inaccurate diagnosis due to tumor heterogeneity. Herein, we developed a zirconium-89 (⁸⁹Zr)-radiolabeled M9346A (⁸⁹Zr-M9346A) as an immuno-positron emission tomography (immuno-PET) radiotracer to evaluate FRα expression in triple-negative breast cancer (TNBC) patients, providing a novel means to guide intervention with therapeutic IMGN853. In this study, we verified the binding specificity and immunoreactivity of ⁸⁹Zr-M9346A by in vitro studies in FRα^high cells (HeLa) and FRα^low cells (OVCAR-3). In vivo PET/computed tomography (PET/CT) imaging in HeLa xenografts and TNBC patient-derived xenograft (PDX) mouse models with various levels of FRα expression demonstrated its targeting specificity and sensitivity. Following PET imaging, the treatment efficiencies of IMGN853, pemetrexed, IMGN853 + pemetrexed, paclitaxel, and saline were assessed in FRα^high and FRα^low TNBC PDX models. The correlation between ⁸⁹Zr-M9346A tumor uptake and treatment response using IMGN853 in FRα^high TNBC PDX model suggested the potential of ⁸⁹Zr-M9346A PET as a noninvasive tool to prescreen patients based on the in vivo PET imaging for IMGN853-targeted treatment.

Ramucirumab and irinotecan in patients with previously treated gastroesophageal adenocarcinoma

TPS4150

Background: Ramucirumab is used for treatment of metastatic gastroesophageal adenocarcinoma after disease progression on first-line chemotherapy. Superior survival outcome is expected when combined with paclitaxel. However, many patients suffer from neuropathy after oxaliplatin-containing first-line chemotherapy and are unable to tolerate paclitaxel. Irinotecan has shown survival benefit as a single agent or in combination with other agents, but has not been used in combination with ramucirumab for treatment with gastroesophageal cancer. We hypothesize that this combination regimen of irinotecan plus ramucirumab administered as second-line treatment will be well-tolerated with improved outcomes similar to paclitaxel plus ramucirumab in patients with advanced gastroesophageal cancer. Circulating levels of angiogenic factors are correlatives of particular interest in this study. Methods: This is a multi-institutional, single-arm phase II clinical trial of ramucirumab and irinotecan. Primary objective of the study is to determine the progression-free survival in patients treated with this combination after disease progression on first-line chemotherapy. Secondary objectives are to determine other indices of efficacy including overall survival, time to progression, objective response rate, and clinical benefit rate; and to evaluate toxicity and tolerability. Patients with confirmed diagnosis of gastroesophageal adenocarcinoma with measurable disease are included. Patients are required of have disease progression during or within 4 months of first line chemotherapy. Key exclusion criteria include squamous histology; prior irinotecan or ramucirumab use; active brain metastases; or other contraindications to ramucirumab including recent history of gastrointestinal bleeding or perforation, thromboembolic event, and uncontrolled hypertension. Patients receive ramucirumab 8mg/kg with irinotecan 180mg/m2 IV every 14 days. We plan to enroll 40 patients which will provide 85% power at a 0.05 significance level to detect a median progression free survival time of 4 months compared to historic control of 2.5 months. 25% of patient accrual is complete as of February 2019. Clinical trial information: NCT03141034.

A phase Ib trial of anti-VEGFR/PDGFR vorolanib combined with immune checkpoint inhibitors (CPIs) in solid tumors

TPS472

Background: Immune CPIs have become a standard treatment option for many advanced malignancies, including gastric (G)/GE junction (GEJ) and hepatocellular cancer (HCC), but resistance is inevitable. Data suggests angiogenesis plays a key role in tumor-mediated immune regulation. Vascular endothelial growth factor (VEGF) can inhibit intra-tumor T cell trafficking, while anti-VEGF therapy can improve T cell infiltration, potentially enhancing response to CPIs to overcome resistance. Vorolanib (V), a potent oral VEGFR/PDGFR inhibitor, has anti-angiogenic properties with a favorable toxicity profile. This phase 1b study is aimed to assess the safety and efficacy of V + CPIs, pembrolizumab (P) or nivolumab (N), in pts with advanced solid tumors. Methods: The primary objective is to determine the recommended phase 2 dose (RP2D) of V + CPIs. Secondary objectives include safety, toxicity and objective response rate (ORR) and survival outcomes. Correlatives include analysis of angiogenic factors and tumor infiltrating lymphocytes as response biomarkers in archived tumor tissue and peripheral blood. Key eligibility for dose escalation cohort includes pts with solid tumors who can receive standard P or N, and for dose expansion cohort includes pts with PD-L1+ G/GEJ cancer who progressed on one or two lines of chemo, refused or are not candidates for chemo; or HCC Child-Pugh A treated with or refused sorafenib, ECOG PS 0-1 and adequate organ function. Key exclusions include prior CPI, significant bleeding, thrombosis, autoimmune disease or condition requiring corticosteroid use. A 3+3 design will be utilized to determine maximum tolerated dose and RP2D. V starts at 300 mg PO daily, pts receive N 480 mg IV Q 28-day cycle or P 200 mg IV Q 21-day cycle (max 36 pts). Dose level advancement occurs when all pts complete cycle 1 of assessed level. 20 additional pts (10 HCC, 10 G/GEJ cancer) will be treated at RP2D. Response assessment by RECIST v1.1 occurs Q 3 cycles on P or Q 2 cycles on N. ORR of 20% or greater warrants further investigation. Enrollment is ongoing. Clinical trial information: NCT03511222.

Concurrent HER or PI3K Inhibition Potentiates the Antitumor Effect of the ERK Inhibitor Ulixertinib in Preclinical Pancreatic Cancer Models

Effective treatment for pancreatic ductal adenocarcinoma (PDAC) is an urgent, unmet medical need. Targeting KRAS, the oncogene that is present in >95% of PDAC, is a heavily pursued strategy, but remains unsuccessful in the clinic. Therefore, targeting key effector cascades of KRAS oncoprotein, particularly the mitogenic RAF-MEK-ERK pathway, represents the next best strategy. However, RAF or MEK inhibitors have failed to show clinical efficacy in PDAC. Several studies have shown that cancer cells treated with RAF or MEK inhibitors adopt multiple mechanisms to reactivate ERK signaling. Therefore, development of ERK-specific inhibitors carries the promise to effectively abrogate this pathway. Ulixertinib (or BVD-523) is a first-in-class ERK-specific inhibitor that has demonstrated promising antitumor activity in a phase I clinical trial for advanced solid tumors with NRAS and BRAF mutations, providing a strong rationale to test this inhibitor in PDAC. In this study, we show that ulixertinib effectively inhibits in vitro growth of multiple PDAC lines and potentiates the cytotoxic effect of gemcitabine. Moreover, we found that PDAC cells treated with ulixertinib upregulates the parallel PI3K-AKT pathway through activating the HER/ErbB family proteins. Concurrent inhibition of PI3K or HER proteins synergizes with ulixertinib in suppressing PDAC cell growth in vitro and in vivo Overall, our study provides the preclinical rationale for testing combinations of ulixertinib with chemotherapy or PI3K and HER inhibitors in PDAC patients. Mol Cancer Ther; 17(10); 2144-55. ©2018 AACR.

Abstract 2375: Concurrent HER or PI3K inhibition potentiates the anti-tumor effect of ERK inhibitor BVD-523 (ulixertinib) in preclinical pancreatic cancer models

To date, effective treatments for inoperable pancreatic ductal adenocarcinoma (PDAC) remain elusive. Targeting KRAS, the gene that is mutated in >95% of PDAC, is a heavily pursued strategy, but unsuccessful in the clinic. Therefore, targeting key effector cascades of KRAS oncoprotein, particularly the mitogenic RAF-MEK-ERK represents the next best strategy. However, RAF or MEK inhibitors have not shown promising clinical efficacy in PDAC. Several studies have shown that cancer cells treated with RAF or MEK inhibitors adopt multiple mechanisms to re-activate ERK signaling. Therefore, development of ERK-specific inhibitors carries the promise to effectively abrogate this pathway. BVD-523 (ulixertinib) is a first-in-class ERK-specific inhibitor that has demonstrated anti-tumor activity in clinical trials. In this study, we showed that BVD-523 effectively inhibits transformed growth of multiple PDAC lines and potentiates the cytotoxic effect of gemcitabine. Moreover, using reverse-phase protein array analysis, we identified potential mechanisms by which PDAC cells may adopt to tolerate ERK inhibition. On this basis, we proposed and tested two rational combinatorial approaches with BVD-523 that showed promising preclinical efficacy in vitro and in mouse xenografts. Overall, we provide the first evidence that PDAC cells may readily adapt to pharmacologic ERK inhibition, and provide combinatorial therapeutic strategies that could benefit patients.

Citation Format: Hongmei Jiang, Mai Xu, Lin Li, Maureen Highkin, Daoxiang Zhang, Qiong Li, Andrea Wang-Gillam, Kian-Huat Lim. Concurrent HER or PI3K inhibition potentiates the anti-tumor effect of ERK inhibitor BVD-523 (ulixertinib) in preclinical pancreatic cancer models [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 2375.

Tumor-Stroma IL1β-IRAK4 Feedforward Circuitry Drives Tumor Fibrosis, Chemoresistance, and Poor Prognosis in Pancreatic Cancer

Targeting the desmoplastic stroma of pancreatic ductal adenocarcinoma (PDAC) holds promise to augment the effect of chemotherapy, but success in the clinic has thus far been limited. Preclinical mouse models suggest that near-depletion of cancer-associated fibroblasts (CAF) carries a risk of accelerating PDAC progression, underscoring the need to concurrently target key signaling mechanisms that drive the malignant attributes of both CAF and PDAC cells. We previously reported that inhibition of IL1 receptor-associated kinase 4 (IRAK4) suppresses NFκB activity and promotes response to chemotherapy in PDAC cells. In this study, we report that CAF in PDAC tumors robustly express activated IRAK4 and NFκB. IRAK4 expression in CAF promoted NFκB activity, drove tumor fibrosis, and supported PDAC cell proliferation, survival, and chemoresistance. Cytokine array analysis of CAF and microarray analysis of PDAC cells identified IL1β as a key cytokine that activated IRAK4 in CAF. Targeting IRAK4 or IL1β rendered PDAC tumors less fibrotic and more sensitive to gemcitabine. In clinical specimens of human PDAC, high stromal IL1β expression associated strongly with poor overall survival. Together, our studies establish a tumor-stroma IL1β-IRAK4 feedforward signal that can be therapeutically disrupted to increase chemotherapeutic efficacy in PDAC.Significance: Targeting the IL1β-IRAK4 signaling pathway potentiates the effect of chemotherapy in pancreatic cancer. Cancer Res; 78(7); 1700-12. ©2018 AACR.

Phase I study of hepatic arterial infusion (HAI) therapy with floxuridine (FUDR) combined with systemic gemcitabine and oxaliplatin in patients with locally advanced intrahepatic cholangiocarcinoma (ICC)

417

Background: The standard of care for unresectable ICC is palliative systemic chemotherapy with cisplatin and gemcitabine. HAI therapy with FUDR in ICC resulted in high response rates [Kemeny 2011]. The use of HAI FUDR with systemic chemotherapy may improve outcomes. We conducted a phase 1 study of HAI FUDR with systemic gemcitabine and oxaliplatin. Methods: We enrolled patients in 3 cohorts: FUDR 0.16mg/kg/day x 14 days (Cohort 1), FUDR 0.12 mg/kg/day x 14 days with gemcitabine 1000mg/m2 on days 1, 8, 15 (Cohort 2), and FUDR 0.10 mg/kg/day x 14 days with gemcitabine 800mg/m2 days 1, 15 and oxaliplatin 85mg/m2 days 1, 15 (Cohort 3). The primary endpoint was the recommended phase 2 dose (RP2D) for Cohort 3. DLTs were assessed during cycle 1. Secondary objectives were response rate and survival. Results: We enrolled 24 patients, 6 male, age range 42-81 years (median 64). No DLTs were observed in Cohort 1 (FUDR). In Cohort 2 (FUDR + Gem), the addition of gemcitabine at 1000mg/m2 days 1, 8, 15 resulted in grade 3 LFT elevation in 2 patients; for subsequent patients, the gemcitabine dose was reduced to 800mg/m2, and no further DLT were noted. No DLT were observed in Cohort 3 (FUDR + GemOx). 10 patients experienced partial responses and conversion to resectable disease occurred in all cohorts. No other significant toxicities occurred. Conclusions: FUDR via HAI with systemic gemcitabine and oxaliplatin is well-tolerated in patients with unresectable cholangiocarcinoma, with a high rate of response and disease control, allowing for resection in some patients. Our RP2D is FUDR 0.10 mg/kg/day x 14 days, with gemcitabine 800mg/m2 days 1, 15 and oxaliplatin 85mg/m2 days 1, 15. Collaboration with MSKCC is ongoing. Clinical trial information: NCT01525069. [Table: see text]

A phase II trial of first-line FOLFIRINOX for patients with advanced gastroesophageal adenocarcinoma

89

Background: Standard first-line regimens for patients with metastatic gastroesophageal adenocarcinomas have an approximate 40% objective response rate (ORR). FOLFIRINOX has been used in first line therapy in other GI cancers (i.e pancreatic and CRC) with impressive efficacy signals. Methods: This is a phase II study of first line combination chemotherapy with fluorouracil (5-FU), irinotecan, and oxaliplatin in patients with advanced gastric, esophageal, or gastroesophageal junction adenocarcinoma (NCT01928290). Starting doses were 5-FU 400mg/m2 bolus followed by 2400 mg/m2 over 46 hours with leucovorin 400 mg/m2, irinotecan 180 mg/m2, and oxaliplatin 85 mg/m2. Trastuzumab was administered as 6 mg/kg loading dose then 4 mg/kg every 14 days if patients had HER2+ cancer. The primary endpoint was overall response rate (ORR). Secondary endpoints included progression free survival (PFS), overall survival (OS), time to progression (TTP), clinical benefit rate (CBR), and duration of response. Enrollment of 41 patients with HER2- disease was planned to reach one-sided = 0.10 and power 0.90 with goal of detecting true ORR60%. No enrollment goal was planned for HER2+. Results: From Nov 2013 to July 2017, 58 patients were enrolled, 25 out of 58 (43%) had HER2+ disease. Forty-nine patients were evaluable for response as they completed at least one restaging scan. ORR was 78% (38/49) in all patients, 67% (18/27) in HER2-, 91% (20/22) in HER2+. One patient (2%) had complete response, 37 (76%) had partial response, 7 (14%) had stable disease > 6 months; therefore, CBR was 92%. Median PFS is 11.9 months, median OS is 17.4 months and median follow up time 16.1 months. 41 (83.7%) had dose modification or delay during treatment. There were no unexpected toxicities. Conclusions: FOLFIRINOX with or without trastuzumab showed remarkable ORR and PFS in patients with advanced gastroesophageal adenocarcinoma in the first-line setting. This regimen may be a reasonable therapeutic option for patients with preserved performance status. Further investigation in larger population is warranted. Clinical trial information: NCT01928290.

Phase I study of defactinib combined with pembrolizumab and gemcitabine in patients with advanced cancer

380

Background: Focal adhesion kinase (FAK) is consistently hyperactivated in multiple tumor types including pancreatic ductal adenocarcinoma (PDAC). Our preclinical work showed that FAK and PD-1 inhibitors elicit significant tumor regression, and a maximal response is achieved by combining FAK and PD-1 inhibitors with gemcitabine, suggesting the need for a cytotoxic agent to bolster antigen presentation (Jiang H et al, Nature Medicine 2016). Defactinib is an orally available, well-tolerated, potent ATP-competitive FAK inhibitor. Methods: Eligible patients are being treated according to the dose escalation schema (Table 1). A 3+3 design is being used. The study has an expansion portion for PDAC patients at the recommended phase 2 dose (RP2D). The primary endpoint is to determine the RP2D. Secondary endpoints include safety, toxicity, objective response rate, progression-free survival and overall survival. The exploratory endpoints include developing a molecular and immune profile for treatment response. Results: The dose escalation cohort has been completed with a total of 17 patients with refractory solid tumors being enrolled. The common treatment-related adverse events included fatigue (35%), nausea (29%), myalgia (29%), vomiting (24%), anorexia (24%), pruritus (24%) and fever (18%). No DLTs were observed, therefore the Level 5 dose was deemed to be the RP2D. Among the 13 patients evaluable for treatment response, 7 (54%) have stable disease. No partial or complete responses were observed to date. The median time on treatment was 127 days for all evaluable patients, and 104 days in the 6 PDAC patients with the longest time on treatment being 290 days. Paired biopsies in PDAC patients showed decreased p-FAK and changes in T cells infiltration and proliferation with treatment. Conclusions: The combination regimen is well tolerated. Dose Level 5 is the RP2D dose. The expansion cohort (PDAC only) is ongoing. Efficacy and correlative data is forthcoming. Dose LevelDefactinib D1-21 (BID)Pembrolizumab Gemcitabine (D1 and 8) Level 1 200 mg 200 mg- Level 2 400 mg 200 mg- Level 3 400 mg 200 mg 500 mg/m2 Level 4 400 mg 200 mg 750 mg/m2 Level 5 400 mg 200 mg 1,000 mg/m2 Clinical trial information: NCT02546531.

Distinct clinical and magnetic resonance features of metastatic hepatocellular carcinoma treated with pembrolizumab: A case report of late response after pseudoprogression

There are few effective therapies for unresectable or metastatic hepatocellular carcinoma. Recent data have demonstrated efficacy of immune checkpoint blockade in this difficult to treat disease; however, clinical experience is limited. We report a case of hepatocellular carcinoma displaying pseudoprogression followed by a late response with novel magnetic resonance imaging features following treatment with the anti-programmed cell death protein 1 agent pembrolizumab. (Hepatology Communications 2018;2:148-151).

Pacritinib to inhibit JAK/STAT signaling in refractory metastatic colon and rectal cancer

Background

Treatment options for patients with refractory colorectal cancer are limited and typically provide a chance of only modest benefit. The goal of this study was to evaluate the benefit of inhibiting the JAK/STAT inflammatory pathway with single agent pacritinib in patients with metastatic refractory colorectal adenocarcinoma.

Methods

A single arm institutional trial was initiated and enrolled patients with metastatic colorectal cancer refractory to at least two standard lines of treatment. Pacritinib 400 mg daily was administered orally continuously in 28 day cycles.

Results

The trial was discontinued prior to reaching the planned accrual due to an FDA hold on pacritinib and a lack of treatment benefit. Eleven patients were enrolled and seven were evaluated for response. Median baseline C-reactive protein level was 12.1 (2.1-147) mg/L. One patient had stable disease at eight weeks by RECIST criteria and six progressed. There were no grade 4 or 5 adverse events while patients were on study. The grade 2 and lower AE events experienced were consistent with prior pacritinib trials.

Conclusions

In seven evaluable patients there were no objective responses. The trial was discontinued prior to completing planned accrual based on a low likelihood that the progression free survival goal of 4 months would be met.

Validity of self-reported weight and height: a cross-sectional study among Malaysian adolescents

Background

Self-reported weight and height are commonly used in lieu of direct measurements of weight and height in large epidemiological surveys due to inevitable constraints such as budget and human resource. However, the validity of self-reported weight and height, particularly among adolescents, needs to be verified as misreporting could lead to misclassification of body mass index and therefore overestimation or underestimation of the burden of BMI-related diseases. The objective of this study was to determine the validity of self-reported weight and height among Malaysian secondary school children.

Methods

Both self-reported and directly measured weight and height of a subgroup of 663 apparently healthy schoolchildren from the Malaysian Adolescent Health Risk Behaviour (MyAHRB) survey 2013/2014 were analysed. Respondents were required to report their current body weight and height via a self-administrative questionnaire before they were measured by investigators. The validity of self-reported against directly measured weight and height was examined using intraclass correlation coefficient (ICC), the Bland-Altman plot and weighted Kappa statistics.

Results

There was very good intraclass correlation between self-reported and directly measured weight [r = 0.96, 95% confidence interval (CI): 0.93, 0.97] and height (r = 0.94, 95% CI: 0.90, 0.96). In addition the Bland-Altman plots indicated that the mean difference between self-reported and direct measurement was relatively small. The mean difference (self-reported minus direct measurements) was, for boys: weight, −2.1 kg; height, −1.6 cm; BMI, −0.44 kg/m² and girls: weight, −1.2 kg; height, −0.9 cm; BMI, −0.3 kg/m². However, 95% limits of agreement were wide which indicated substantial discrepancies between self-reported and direct measurements method at the individual level. Nonetheless, the weighted Kappa statistics demonstrated a substantial agreement between BMI status categorised based on self-reported weight and height and the direct measurements (kappa = 0.76, 95% CI: 0.67, 0.84).

Conclusion

Our results show that the self-reported weight and height were consistent with direct measurements and therefore can be used in assessing the nutritional status of Malaysian school children from the age of 13 to 17 years old in epidemiological studies and for surveillance purposes when direct measurements are not feasible, but not for assessing nutritional status at the individual level.

Current biologics for treatment of biliary tract cancers

Biliary tract cancers (BTC) is a group of malignancies that arise from the epithelial cells of the biliary tree. These cancers are typically classified by anatomic site of origin: intrahepatic cholangiocarcinoma (IHCC) and extrahepatic cholangiocarcinoma (EHCC), and gallbladder cancer (GBC). To date, complete surgical resection remains the mainstay of treatment especially for earlier stage disease. Unfortunately, most patients present with advanced or metastatic disease, when systemic chemotherapy is the only treatment option. Due to the paucity of effective treatments, BTCs have a dismal prognosis. There is a tremendous need to better understand the disease biology, discover new therapies, and improve clinical outcomes for this challenging disease. Next-generation sequencing has produced a more accurate and detailed picture of the molecular signatures in BTCs. The three BTC histologic subtypes are, in fact, quite molecularly distinct. IHCC commonly contain FGFR2 fusions and IDH 1 and 2 mutations, whereas EHCC and GBC tend to carry mutations in EGFR, HER2, and MAPK pathway. In light of this emerging knowledge, clinical trials have become more biomarker-driven, which allows capturing of subsets of patients that are most likely to respond to certain therapies. Many new and promising targeted therapeutics are currently in the pipeline. Here we review the genetic landscape of BTCs while focusing on new molecular targets and targeted therapeutics currently being investigated in biomarker-driven clinical trials.

Immunotherapy in gastrointestinal cancers

Gastrointestinal (GI) cancers such as gastric, esophageal, pancreas, hepatobiliary, colorectal and anal cancers are a major cause of cancer related mortality worldwide. Traditional treatment options such as chemotherapy, surgery, radiation therapy, monoclonal antibodies and anti-angiogenic agents have been the backbone of treatment of GI cancers in various stages. Current cancer research is moving forward to incorporate immunotherapies in the treatment of GI cancers either as single agent or in combination with current available treatment modalities. This review summarizes the existing and ongoing immunotherapies in the treatment of GI cancers.

Molecular landscape and sub-classification of gastrointestinal cancers: a review of literature

The historical approach of diagnosing cancer types based entirely on anatomic origin and histologic features, and the "one-size-fit-all" therapeutic approach, are inadequate in modern cancer treatment. From decades of research we now know that cancer is a highly heterogeneous disease driven by complex genetic or epigenetic alterations. The advent of various high throughput molecular tools has now enabled us to view and sub-classify each cancer type based on their distinct molecular features, in addition to histologic classification, with the promise of individualized treatment strategies tailored towards each specific subtype to improve patient outcomes. In this review, we have made an effort to systematically review the most up-to-date, leading literature in molecular analysis and/or subtyping of major gastrointestinal cancers. These include esophageal squamous cell carcinoma (ESCC), gastric cancer (GC) adenocarcinoma, pancreatic ductal adenocarcinoma (PDAC), hepatocellular carcinoma (HCC), gallbladder cancer (GBC), and colorectal cancer (CRC). For each cancer type we summarized the global mutational landscape, subgroup classification based on genomics, epigenetics, gene expression and/or proteomic analysis, and their salient clinicopathological features. We have highlighted the actionable mutations or mutational pathways that could help guide targeted therapies in the future.

Phase I study combining MLN8237 with nab-paclitaxel in patients with advanced solid malignancies

2553

Background: MLN8237 is a potent Aurora A kinase inhibitor which synergizes with paclitaxel in preclinical studies for various solid malignancies. Methods: We conducted a two-part, phase 1 study combining MLN8237 with nab-paclitaxel in patient with advanced, refractory solid malignancies (NCT01677559). The part 1, dose-escalation phase utilizes a standard a 3+3 design for determination of maximum tolerated dose (MTD) and dose limiting toxicities (DLTs), starting from nab-Paclitaxel 100mg/m2/week 3 out of a 4-week cycle, and MLN8237 20mg BID D1-3/week (denoted nP/M 100/20). In the part 2, dose-expansion cohort, patients with advanced pancreatic ductal adenocarcinoma (PDAC) or high grade neuroendocrine tumor (pNET) who progressed on standard chemotherapy were enrolled. Results: Totally 33 patients (17 in part 1 and 16 in part 2) with a median age of 61 were enrolled. In part 1, the most frequent treatment-related toxicities (all Grade/Grade 3-4) were: nausea (65%/6%), neutropenia (61%/18%), fatigue (47%/6%), anorexia (47%/0%), oral mucositis (53%/6%) and anemia (35%/18%). Two of 3 patients experienced a DLT at dose nP/M 100/50 (Grade 4 neutropenia; febrile neutropenia). No treatment-related mortality occurred. MTD was set at nP/M 100/40 for part 2. At data cutoff, totally 20 patients from the entire study were evaluable for treatment response. One patient with small cell lung cancer achieved partial response and is in cycle 29. Nine other patients (9/20, 45%) with the following tumor histology achieved stable disease after two cycles: 1 small cell lung cancer, 1 lung neuroendocrine carcinoma, 1 lung squamous cell carcinoma, 1 PDAC and 5 high grade pNET (range: 3 and ongoing ~ 18 cycles). Conclusions: MLN8237 plus nab-paclitaxel has manageable side effect profile with very promising activity in tumors with high grade neuroendocrine features, warranting further testing. Exploratory studies on pharmacodynamic markers are ongoing. Clinical trial information: NCT01677559.

A clinically feasible multiplex proteomic immunoassay as a novel functional diagnostic for pancreatic ductal adenocarcinoma

To date, targeted therapy for pancreatic ductal adenocarcinoma (PDAC) remains largely unsuccessful in the clinic. Current genomics-based technologies are unable to reflect the quantitative, dynamic signaling changes in the tumor, and require larger tumor samples that are difficult to obtain in PDAC patients. Therefore, a highly sensitive functional tool that can reliably and comprehensively inform intra-tumoral signaling events is direly needed to guide treatment decision. We tested the utility of a highly sensitive proteomics-based functional diagnostic platform, Collaborative Enzyme Enhanced Reactive-immunoassay (CEERTM), on fine-needle aspiration (FNA) samples obtained from 102 patients with radiographically-evident pancreatic tumors. Two FNA passes were collected from each patient, hybridized to customized chips coated with an array of capture antibodies, and detected using two enzyme-conjugated antibodies which emit quantifiable signals. We demonstrate that this technique is highly sensitive in detecting total and phosphorylated forms of multiple signaling molecules in FNA specimens, with reasonable correlation of marker intensities between two different FNA passes. Notably, signals of several markers were significantly higher in PDAC compared to non-cancerous samples. In PDAC samples, we found high total c-Met signal to be associated with poor survival, and confirmed this finding using an independent PDAC tissue microarray.

Phase I study of defactinib combined with pembrolizumab and gemcitabine in advanced cancer

TPS505

Background: Focal adhesion kinase (FAK) is consistently hyperactivated in pancreatic ductal adenocarcinoma (PDAC), and FAK signaling is a key driver in forming its fibrotic and proinflammatory tumor microenvironment. Inhibition of FAK signaling leads to significant reduction of pancreatic tumor growth in animal models. Indeed, tumors treated with FAK inhibitors displayed markedly reduced tumor fibrosis and decreased immunosuppressive myeloid cells. Furthermore, our preclinical work has demonstrated that FAK- and PD-1 inhibitors elicit significant tumor regression, and the maximal response was achieved by combining FAK- and PD-1 inhibitors with gemcitabine, suggesting the need for a cytotoxic agent to bolster antigen presentation (Jiang H et al, Nature Medicine 2016). Defactinib is an orally available, potent ATP-competitive, FAK inhibitor with a recommended phase II dose (RP2D) of 400 mg twice daily. Methods: Eligible patients will be treated according to the dose escalation schema. A 3+3 design is used until the first occurrence of dose-limiting toxicity, and then switches to a continuous assessment design. The study has an expansion portion (group A and B) at the RP2D. Group A includes metastatic PDAC patients who are stable at least 4 months on front-line nab-paclitaxel/gemcitabine, and group B includes metastatic PDAC patients progressed on ≥ 1 chemotherapy line. Key eligibility criteria include patients with advanced solid tumors (dose escalation portion) or advanced PDAC (expansion cohort); age ≥18 years; ECOG score ≤1; normal organ function; and no history autoimmunity. The primary endpoint is to determine the RP2D. Secondary endpoints include objective response rate, progression-free survival and overall survival. The exploratory endpoints include developing a molecular and immune signature for treatment response. This trial is actively enrolling and funded by Precision Medicine Research Associate and Barnes Jewish Foundation. Clinical trial information: NCT02546531. [Table: see text]

Utility of a multidisciplinary tumor board in the management of pancreatic and upper gastrointestinal diseases: an observational study

BACKGROUND & OBJECTIVES

Multidisciplinary tumor boards (MDTBs) are frequently employed in cancer centers but their value has been debated. We reviewed the decision-making process and resource utilization of our MDTB to assess its utility in the management of pancreatic and upper gastrointestinal tract conditions.

METHODS

A prospectively-collected database was reviewed over a 12-month period. The primary outcome was change in management plan as a result of case discussion. Secondary outcomes included resources required to hold MDTB, survival, and adherence to treatment guidelines.

RESULTS

Four hundred seventy cases were reviewed. MDTB resulted in a change in the proposed plan of management in 101 of 402 evaluable cases (25.1%). New plans favored obtaining additional diagnostic workup. No recorded variables were associated with a change in plan. For newly-diagnosed cases of pancreatic ductal adenocarcinoma (n = 33), survival time was not impacted by MDTB (p = .154) and adherence to National Comprehensive Cancer Network guidelines was 100%. The estimated cost of physician time per case reviewed was $190.

CONCLUSIONS

Our MDTB influences treatment decisions in a sizeable number of cases with excellent adherence to national guidelines. However, this requires significant time expenditure and may not impact outcomes. Regular assessments of the effectiveness of MDTBs should be undertaken.

Analysis of the effect of adjuvant therapy on overall survival for resected gallbladder adenocarcinoma using the National Cancer Database

360

Background: The effect of adjuvant chemotherapy on survival after resection for gallbladder adenocarcinoma (GBC) is based on limited evidence. Since prospective trials are not generally practical for GBC, we sought to evaluate current best evidence to evaluate the role of adjuvant chemotherapy in multiple clinical scenarios by analyzing data from the U.S. National Cancer Database (NCDB). Methods: Patients who underwent resection for GBC diagnosed between 2004 and 2012 were identified in the NCDB. The effect of adjuvant therapy on overall survival (OS) was assessed using Kaplan-Meier analysis and Cox proportional hazards regression modeling. Results: 10,402 patients met inclusion criteria. Median follow-up was 14 months. Median survival was 16 months. One- and five-year OS were 57% and 23%, respectively. 3,509 patients (34%) received any modality of adjuvant therapy. Receipt of adjuvant therapy improved one-year OS (63% vs 55%, p < 0.01), but median OS was minimally changed (17 vs 15 months, NS). Adjuvant therapy was associated with improved one-year OS in T3 and T4N1 disease (Table 1). Only chemoradiation therapy was associated with improved one-year OS for T2 disease. Adjuvant chemotherapy was associated with worse one-year OS in T1N0 disease. Conclusions: Using data from the US NCDB, adjuvant therapy for resected gallbladder adenocarcinoma is associated with improved one-year overall survival with the exception of T1N0 disease. In the absence of prospective studies in this rare disease, retrospective data can provide insights into successful treatment strategies and guidelines for GBC. [Table: see text]

A phase I/II study combining tosedostat with capecitabine in patients with metastatic pancreatic ductal adenocarcinoma (PDAC)

410

Background: Recent advances in front-line therapy have improved survival in patients with advanced PDAC. A fluorouracil-based regimen is recommended for patients who progress on a gemcitabine-based therapy. Tosedostat is an oral aminopeptidase inhibitor that disrupts the cleavage of amino acids from peptides downstream of proteasomal degradation. It prevents the recycling of free amino acids, leads to intracellular depletion of amino acids, and triggers an amino acid deprivation response that subsequently results in apoptosis. Because PDAC cells frequently upregulate expression of these aminopeptidases, tosedostat offers therapeutic promise, particularly in combination with fluoropyrimidines. Methods: This is a single institution phase I/II trial to evaluate the safety and toxicity of tosedostat plus capecitabine in patients with metastatic PDAC progressed on a gemcitabine-based therapy. The phase I portion is being conducted in a dose de-escalation fashion, with two dose levels of tosedostat (120 mg or 60 mg) p.o. daily on days 1 to 21 with capecitabine 1000 mg/m2 p.o. BID on days 1 to 14 of a 21-day cycle. If more than one out of 6 patients in the tosedostat (120 mg) cohort experience a dose limiting toxicity (DLT), then 6 more will be enrolled to the tosedostat (60 mg) cohort. The primary objective of the phase I portion is to determine the optimal phase II dose. The primary objective of the phase II portion is to determine the progression-free survival at 3 months. Secondary objectives include the overall response rate, overall survival and CA 19-9 response. To avoid futility, interim analysis is planned after 10 evaluable patients enrolled. Results: Up to date, a total of 11 patients have been enrolled in the study, and 10 patients are evaluable. No DLT have been observed. Tosedostat at a dose of 120 mg with capecitabine is extremely well tolerated. Prolonged stable disease has been observed in 4 (40%) patients with a time on treatment of 10 months, 7.5 months, 5.5 months and 4 months, and 3 of the 4 patients remain on the trial. Conclusions: The combination of tosedostat and capecitabine is a well-tolerated regimen with impressive clinical activity in the subset of patients studied thus far. Clinical trial information: NCT02352831.

Steroid Responsive Mononeuritis Multiplex in the Cronkhite-Canada Syndrome

The Cronkhite-Canada syndrome (CCS) is a rare disorder of unknown origin characterized by generalized gastrointestinal polyposis, alopecia, hyperpigmentation, and onychodystrophy. We report a case of CCS with concomitant presentation of mononeuritis multiplex. The electrophysiological findings and steroid responsiveness suggests presence of an autoimmune mechanism.

Constitutive IRAK4 Activation Underlies Poor Prognosis and Chemoresistance in Pancreatic Ductal Adenocarcinoma

Purpose: Aberrant activation of the NF-κB transcription factors underlies the aggressive behavior and poor outcome of pancreatic ductal adenocarcinoma (PDAC). However, clinically effective and safe NF-κB inhibitors are not yet available. Because NF-κB transcription factors can be activated by the interleukin-1 receptor-associated kinases (IRAKs) downstream of the Toll-like receptors (TLRs), but has not been explored in PDAC, we sought to investigate the role of IRAKs in the pathobiology of PDAC.Experimental Design: We examined the phosphorylation status of IRAK4 (p-IRAK4), the master regulator of TLR signaling, in PDAC cell lines, in surgical samples and commercial tissue microarray. We then performed functional studies using small-molecule IRAK1/4 inhibitor, RNA-interference, and CRISPR/Cas9n techniques to delineate the role of IRAK4 in NF-κB activity, chemoresistance, cytokine production, and growth of PDAC cells in vitro and in vivoResults: p-IRAK4 staining was detectable in the majority of PDAC lines and about 60% of human PDAC samples. The presence of p-IRAK4 strongly correlated with phospho-NF-κB/p65 staining in PDAC samples and is predictive of postoperative relapse and poor overall survival. Inhibition of IRAK4 potently reduced NF-κB activity, anchorage-independent growth, chemoresistance, and secretion of proinflammatory cytokines from PDAC cells. Both pharmacologic suppression and genetic ablation of IRAK4 greatly abolished PDAC growth in mice and augmented the therapeutic effect of gemcitabine by promoting apoptosis, reducing tumor cell proliferation and tumor fibrosis.Conclusions: Our data established IRAK4 as a novel therapeutic target for PDAC treatment. Development of potent IRAK4 inhibitors is needed for clinical testing. Clin Cancer Res; 23(7); 1748-59. ©2016 AACR.

Abstract 181: Constitutive IRAK1/4 kinase activation contributes to NF-kB activity and chemoresistance in pancreatic cancer

Constitutive activation of the NF-κb transcription factor is a major molecular mechanism that contributes to the aggressive behavior and treatment resistance of pancreatic cancer. Understanding the molecular mechanisms that activate NF-κB will provide novel therapeutic opportunities to improve the dismal outcome of pancreatic cancer patients. In the present study, we showed that the Interleukin-1 Receptor-Associated Kinases 1 and 4 (IRAK1 and IRAK4) are constitutively activated in a majority of pancreatic cancer cell lines and patients samples, and are major drivers of NF-κB activity. Notably, we found that constitutive phosphorylation of IRAK4 is associated with poor patient prognosis. Suppression of IRAK1 and IRAK4 with small molecule inhibitor or RNA-interference in pancreatic cancer cells significantly reduces NF-κB activity, three-dimensional growth, invasiveness, production of inflammatory, and augment their sensitivity to chemotherapeutic agents in vitro. Notably, we showed that the NF-κB activity of pancreatic cancer cell with IRAK4 ablated using CRISPR technology can be restored with wild-type, but not kinase-dead IRAK4 mutant, supporting development of IRAK4 inhibitor as a novel therapeutic agent in pancreatic cancer. Silencing of IRAK1 or IRAK4, and more potently both, significantly abrogated the tumorigenic potential of human and murine pancreatic cancer cells as xenograft in mice. Lastly, we showed that IRAK1/4 inhibitor augments the therapeutic effect of gemcitabine in tumor-bearing mice by suppressing proliferation and increasing apoptosis of neoplastic cells, and reducing stromal fibrosis. Together, our data established IRAK4 kinase inhibitors as a promising novel class of targeted agent in pancreatic cancer.

Citation Format: Daoxiang Zhang, Lin Li, Hongmei Jiang, Jinsheng Yu, Brett Knolhoff, Richard Head, Albert C. Lockhart, David G. DeNardo, Andrea Wang-Gillam, Marianna B. Ruzinova, Kian-Huat Lim. Constitutive IRAK1/4 kinase activation contributes to NF-kB activity and chemoresistance in pancreatic cancer. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 181.

Targeting tumour-associated macrophages with CCR2 inhibition in combination with FOLFIRINOX in patients with borderline resectable and locally advanced pancreatic cancer: a single-centre, open-label, dose-finding, non-randomised, phase 1b trial

BACKGROUND

In pancreatic ductal adenocarcinoma, the CCL2-CCR2 chemokine axis is used to recruit tumour-associated macrophages for construction of an immunosuppressive tumour microenvironment. This pathway has prognostic implications in pancreatic cancer, and blockade of CCR2 restores anti-tumour immunity in preclinical models. We aimed to establish the safety, tolerability, and recommended phase 2 oral dose of the CCR2 inhibitor PF-04136309 in combination with FOLFIRINOX chemotherapy (oxaliplatin and irinotecan plus leucovorin and fluorouracil).

METHODS

We did this open-label, dose-finding, non-randomised, phase 1b study at one centre in the USA. We enrolled treatment-naive patients aged 18 years or older with borderline resectable or locally advanced biopsy-proven pancreatic ductal adenocarcinoma, an Eastern Cooperative Oncology Group performance status of 1 or less, measurable disease as defined by Response Evaluation Criteria in Solid Tumors version 1.1, and normal end-organ function. Patients were allocated to receive either FOLFIRINOX alone (oxaliplatin 85 mg/m(2), irinotecan 180 mg/m(2), leucovorin 400 mg/m(2), and bolus fluorouracil 400 mg/m(2), followed by 2400 mg/m(2) 46-h continuous infusion), administered every 2 weeks for a total of six treatment cycles, or in combination with oral PF-04136309, administered at a starting dose of 500 mg twice daily in a standard 3 + 3 dose de-escalation design. Both FOLFIRINOX and PF-04136309 were simultaneously initiated with a total treatment duration of 12 weeks. The primary endpoints were the safety, tolerability, and recommended phase 2 dose of PF-04136309 plus FOLFIRINOX, with an expansion phase planned at the recommended dose. We analysed the primary outcome by intention to treat. This trial is registered with ClinicalTrials.gov, number NCT01413022.

RESULTS

Between April 19, 2012, and Nov 12, 2014, we treated 47 patients with FOLFIRINOX alone (n=8) or with FOLFIRINOX plus PF-04136309 (n=39). One patient had a dose-limiting toxic effect in the dose de-escalation group receiving FOLFIRINOX plus PF-04136309 at 500 mg twice daily (n=6); this dose was established as the recommended phase 2 dose. We pooled patients in the expansion-phase group (n=33) with those in the dose de-escalation group that received PF-04136309 at the recommended phase 2 dose for assessment of treatment-related toxicity. Six (75%) of the eight patients receiving FOLFIRINOX alone were assessed for treatment toxicity, after exclusion of two (25%) patients due to insurance coverage issues. The median duration of follow-up for treatment toxicity was 72·0 days (IQR 49·5-89·0) in the FOLFIRINOX alone group and 77·0 days (70·0-90·5) in the FOLFIRINOX plus PF-04136309 group. No treatment-related deaths occurred. Two (5%) patients in the FOLFIRINOX plus PF-04136309 group stopped treatment earlier than planned due to treatment-related toxic effects. Grade 3 or higher adverse events reported in at least 10% of the patients receiving PF-04136309 included neutropenia (n=27), febrile neutropenia (n=7), lymphopenia (n=4), diarrhoea (n=6), and hypokalaemia (n=7). Grade 3 or higher adverse events reported in at least 10% of patients receiving FOLFIRINOX alone were neutropenia (n=6), febrile neutropenia (n=1), anaemia (n=2), lymphopenia (n=1), diarrhoea (n=2), hypoalbuminaemia (n=1), and hypokalaemia (n=3). Therapy was terminated because of treatment-related toxicity in one (17%) of the six patients receiving FOLFIRINOX alone. 16 (49%) of 33 patients receiving FOLFIRINOX plus PF-04136309 who had undergone repeat imaging achieved an objective tumour response, with local tumour control achieved in 32 (97%) patients. In the FOLFIRINOX alone group, none of the five patients with repeat imaging achieved an objective response, although four (80%) of those patients achieved stable disease.

INTERPRETATION

CCR2-targeted therapy with PF-04136309 in combination with FOLFIRINOX is safe and tolerable.

FUNDING

Washington University-Pfizer Biomedical Collaborative.

Prevalence of smoking and its associated factors with smoking among elderly smokers in Malaysia: findings from a nationwide population-based study

BACKGROUND

The determination of smoking prevalence and its associated factors among the elderly could provide evidence-based findings to guide the planning and implementation of policy in order to will help in reducing the morbidity and mortality of smoking-related diseases, thus increase their quality of life. This paper describes the rate of smoking and identifies the factor(s) associated with smoking among the elderly in Malaysia.

METHODS

A representative sample of 2674 respondents was obtained via a two-stage sampling method in proportion to population size. Face-to-face interviews were conducted using a set of standardized validated questionnaire. Data was weighted by taking into consideration the complex sampling design and non-response rate prior to data analysis. Univariable and multivariable logistic regression were used to determine the factor/s associated with smoking.

RESULTS

The prevalence of non-smokers, ex-smokers and current smokers among Malaysians aged 60 years and above were 36.3 % (95 % CI = 32.7-39.8), 24.4 % (95 % CI = 21.2-27.5) and 11.9 % (95 % CI = 9.5-14.3), respectively. Current smokers were significantly more prevalent in men (28.1 %) than in women (2.9 %), but the prevalence declined with advancing age, higher educational attainment, and among respondents with known diabetes, hypertension and hypercholesterolemia. Multivariable analysis revealed that males (aOR, 18.6, 95 % CI 10.9-31.9) and other Bumiputras (aOR 2.58, 95 % CI 1.29-5.15) were more likely to smoke. in addition, elderly with lower educational attainment (aOR, 1.70, 95 % CI 1.24-7.41) and those without/unknown hypertension also reported higher likelihood to be current smokers (aOR 1.98, 95 % CI 1.35-2.83). However, there were no significant associations between respondents with no/unknown diabetes or hypercholesterolemia with smoking.

CONCLUSIONS

In short, smoking is common among elderly men in Malaysia. Therefore, intervention programs should integrate the present findings to reduce the smoking rate and increase the smoking cessation rate among the elderly in Malaysia and subsequently to reduce the burden of smoking-related disease.

Impact of comorbidities using Adult Comorbidity Evaluation-27 (ACE-27) score on survival in stage II colon cancer: Age, TNM staging, and pathological high risk-disease

659

Background: Impact of comorbidities is identified in stage III colon cancer patients (CCPs) receiving adjuvant chemotherapy (Wildes et al, PMID 21113435) but is not well defined in predicting overall survival (OS) in stage II CCPs undergoing either adjuvant treatment or observation depending upon high-risk disease. The goal of this study was to identify impact of comorbidities on OS in this potentially curable disease using ACE-27 score, which uses 27 different patient comorbid conditions has been developed and validated by Piccirrillo et al at Barnes Jewish Hospital (BJH) (PMID: 24933715). Methods: We identified stage II CCPs treated at BJH, Siteman cancer center from January 1, 1996 to October 31st, 2013 from BJH oncology data cancer registry. The primary outcome was OS, defined as the time from date of surgery to death from any cause, censored at the time of last follow-up. Patient comorbidities at diagnosis were recorded using ACE-27 score, assigning a comorbidity score of none, mild, moderate and severe to the patients. Survival analysis was done using Cox proportional hazard modelling using STATA/SE 11.2 software. Pathological high risk features such as T4 lesions, < 12 LN, perineural, lymphovascular invasion, positive margins & perforation/obstruction were identified. Results: Out of 579 stage II CCPs, 48% male and 51% were females. High risk features were identified in 45% of patients. ACE-27 comorbidity score of none (n = 146), mild (n = 229), moderate (n = 132) and severe (n = 72) was calculated. 497 patients had T3N0M0 and 82 had T4N0M0 staging. Cox regression hazard model using histological prognostic factors, age at surgery, sex, race, prior cancer history and TNM staging showed that ACE-27 score of moderate and severe were independent predictors of OS with a hazard ratio of 1.6 (95% CI 1.0-2.4), P = 0.036 and 2.5 (95% CI 1.5-4.0), P = 0.00 respectively. Conclusions: Highest commodity burden using ACE-27 comorbidity score was associated with poor OS in stage II CCPs and was independent of other prognostic risk factors including high-risk features. Treatment related mortality will be calculated in patients with high risk disease.

A phase I/II study combining tosedostat with capecitabine in patients with metastatic pancreatic adenocarcinoma

TPS471

Background: Metastatic pancreatic ductal adenocarcinoma (PDAC) has a dismal prognosis. Recent advances with fluorouracil in combination with oxaliplatin and irinotecan (FOLFIRINOX) and nab-paclitaxel combined with gemcitabine (AG) have improved survival in patients with PDAC. A fluorouracil-based regimen is recommended for patients who progress after a gemcitabine-based regimen. Tosedostat is an oral aminopeptidase inhibitor shown to have anti-proliferative effects in malignancies. Aminopeptidase inhibitors disrupt the cleavage of amino acids from peptides downstream of proteasomal degradation, preventing the recycling of amino acids needed for new protein synthesis. This leads to intracellular depletion of amino acids, resulting in a cellular stress response known as the amino acid deprivation response, which leads to apoptosis. Because pancreatic cancer cells frequently upregulate expression of these aminopeptidases, aminopeptidases inhibitors hold therapeutic promise. Methods: This is a single institution phase I/II open-label trial to evaluate the safety and tolerability of tosedostat plus capecitabine in patients with metastatic PDAC that have progressed after a gemcitabine-based regimen. The phase I part will be conducted in a dose de-escalation fashion, with two planned dose levels of tosedostat (120mg or 60mg) p.o. daily on days 1 to 21 with capecitabine 1000 mg/m2 p.o. BID on days 1 to 14 of a 21-day cycle. If more than one patient in the tosedostat (120 mg) cohort experiences a dose limiting toxicity (DLT), then 6 more patient will be enrolled to the tosedostat (60 mg) cohort. A total of 36 patients will be enrolled in the phase II portion. Primary objective of the phase I portion is to determine the maximum tolerated dose and DLTs of tosedostat and capecitabine combination therapy. Primary objective of the phase II portion is to determine the progression-free survival at 3 months. Secondary objectives are to determine the overall response rate, time-to-progression, overall survival and CA 19-9 response. Exploratory objectives are to explore the predictive molecular biomarkers for treatment response and to explore the prognostic biomarkers. Clinical trial: NCT02352831. Clinical trial information: NCT02352831.

Prospective phase I study of nab-paclitaxel plus gemcitabine with concurrent MR-guided IMRT in patients with locally advanced or borderline resectable pancreatic cancer

TPS480

Background: Radiotherapy (RT) for locally advanced and borderline resectable pancreatic cancer (LABPC) is controversial as potential local control benefits are often obscured by high rates of distant progression. However, local failure remains a significant cause of morbidity among patients without distant progression after initial chemotherapy, although toxicity concerns may limit delivery of optimal systemic therapy concurrent with RT. Given known systemic efficacy and radiosensitization effects of nab-paclitaxel (A) with gemcitabine (G), we initiated a phase I study of nab-paclitaxel with gemcitabine (AG) and concurrent intensity modulated radiation therapy with magnetic resonance guidance (MR-IMRT) for LABPC. Methods: A planned 24 patients with LABPC will be enrolled to a phase I dose escalation trial using the Time-to-Event Continual Reassessment Method (TITE-CRM) design. Following one lead-in cycle of GA, MR-IMRT is administered daily with concurrent weekly GA for a total of 25 fractions in 5 weeks. The initial dose levels for RT and AG, respectively, are: 40 Gy MR-IMRT, 75 mg/m2 A and 600mg/m2 G. The maximum possible dose level is 60 Gy MR-IMRT, 100mg/m2 A and 1000mg/m2 G. To reduce toxicity risk, MR-IMRT volumes include the primary tumor only, with cine-MR used for intra-fraction tumor tracking in place of fiducial markers. The primary endpoint is determination of the maximum tolerated dose level, with secondary endpoints including rate of conversion to resectable disease, progression- free survival, overall survival, and patient reported quality of life. Clinical trial information: NCT02283372.

Utility of a multidisciplinary tumor board in the management of pancreatic diseases

319

Background: Multidisciplinary Tumor Boards (MTBs) are a requirement for comprehensive cancer centers and are routinely used to coordinate multidisciplinary care in oncology. Despite their widespread use, the impact of MTBs is not well characterized. We studied the outcomes of all patients presented at our pancreas MTB, with the goal of evaluating our current practices and resource utilization. Methods: Data were prospectively collected for all patients presented at a weekly pancreas-specific MTB over the 12-month period at a single-institution NCI-designated cancer center. The conference is attended by surgical, medical, and radiation oncologists, interventional gastroenterologists, pathologists, and radiologists (diagnostic and interventional). Retrospective chart review was performed at the end of the 12-month period under an IRB-approved protocol. Results: A total of 470 patient presentations were made over a 12-month period. Average age at time of presentation was 61.5 years (range 17 – 89) with 51% males. 61.7% of cases were presented by surgical oncologists and 26% by medical oncologists. 174 cases were the result of new diagnoses or referrals. 78 patients were presented more than once (average of 2.3 times). Pancreatic adenocarcinoma was the most common diagnosis (37%), followed by uncharacterized pancreatic mass (16%), and pancreatic cyst (7%). The treatment plan proposed by the presenting clinician was known or could be evaluated prior to conference in 402 cases. Presentation of a case at MTB changed the plan of management 25% (n = 100) of the time, including MTB recommendation against a planned resection in 46 cases. When the initial plan changed as a result of MTB discussion, the most common new plan was to obtain further diagnostic testing such as biopsy and/or endoscopy (n = 24). Conclusions: MTBs are required and resource-intensive but offer the opportunity to discuss a wide array of pathologies and influence management decisions in a sizable proportion of cases. Additional investigations evaluating adherence rates to MTB decisions and to published guidelines (i.e. National Comprehensive Cancer Network) will further enhance the assessment and utility of MTBs.

Eosinophilic gastroenteritis: Clinical profiles and treatment outcomes, a retrospective study of 18 adult patients in a Singapore Tertiary Hospital

BACKGROUND

Eosinophilic gastroenteritis (EG) can mimic symptoms of common gastrointestinal (GI) disorders but responds well to appropriate treatment. Accurate diagnosis is central to effective management. Data on EG in Southeast Asia is lacking. We aim to describe the clinical profiles and treatment outcomes of adult patients with EG in a Singapore Tertiary Hospital.

MATERIALS AND METHODS

This retrospective study involved archival search of patients with GI biopsies that showed eosinophilic infiltration from January 2004 to December 2012. Patients' clinical data from computerised hospital records and clinical notes was reviewed. Diagnostic criteria for EG included presence of GI symptoms with more than 30 eosinophils/high power field on GI biopsies. Patients with secondary causes for eosinophilia were excluded.

RESULTS

Eighteen patients with EG were identified (mean age 52 years; male/female: 11/7). Fifteen patients (83%) had peripheral blood eosinophilia. Seven patients (39%) had atopic conditions. Most common symptoms were diarrhoea and abdominal pain. Small intestine was the most common site involved. Endoscopic finding was non-specific. Ten patients were treated with corticosteroids (nine prednisolone, one budesonide): eight patients (89%) responded clinically to prednisolone but four patients (50%) relapsed following tapering-off of prednisolone and required maintenance dose. One patient each responded to diet elimination and montelukast respectively. Half of the remaining six patients who were treated with proton-pump inhibitors, antispasmodic or antidiarrheal agents still remained symptomatic.

CONCLUSION

Prednisolone is an effective treatment though relapses are common. Small intestine is most commonly involved. EG should be considered in the evaluation of unexplained chronic recurrent GI symptoms.

Advanced pancreatic adenocarcinoma: a review of current treatment strategies and developing therapies

Pancreatic adenocarcinoma is one of the deadliest solid malignancies. A large proportion of patients are diagnosed with locally advanced or metastatic disease at the time of presentation and, unfortunately, this severely limits the number of patients who can undergo surgical resection, which offers the only chance for cure. Recent therapeutic advances for patients with advanced pancreatic cancer have extended overall survival, but prognosis still remains grim. Given that traditional chemotherapy is ineffective in curing advanced pancreatic adenocarcinoma, current research is taking a multidirectional approach in the hopes of developing more effective treatments. This article reviews the major clinical trial data that is the basis for the current chemotherapy regimens used as first- and second-line treatments for advanced pancreatic adenocarcinoma. We also review the current ongoing clinical trials, which include the use of agents targeting the oncogenic network signaling of K-Ras, agents targeting the extracellular matrix, and immune therapies.

FOLFIRINOX as first-line therapy in patients with metastatic gastroesophageal cancers (GEC)

177

Background: Adenocarcinomas of the distal esophagus, gastroesophageal junction and stomach (GEC) remain challenging cancers to treat. Unfortunately, 80-90% of newly diagnosed patients (pts) present with advanced disease where the overall median survival (mOS) is less than 1 year. Discouragingly, various common first-line metastatic regimens have similar overall response rates (ORR) (30-40%; and 47% for HER2+ with trastuzumab). Given results within other GI tumors, FOLFIRINOX was administered to pts with newly diagnosed advanced GEC. Methods: A pooled analysis from two independent ongoing clinical trials was conducted from: 1) the University of Chicago UC (NCT01643499) where pts received modified ‘mFOLFIRINOX’ with irinotecan dosing based on UGT1A1*28 genotyping; and 2) Washington University (WU) (NCT01928290) where pts received standard ‘sFOLFIRINOX’ as previously described, and HER2+ pts also received trastuzumab (sFOLFIRINOX-T). Both studies administered therapy every 14 days. Trastuzumab was administered as 6 mg/kg loading dose then 4 mg/kg every 14 days. mFOLFIRINOX used UGT1A1 genotype *1/*1, *1/*28, and *28/*28 to assign initial irinotecan doses of 180, 135, and 90 mg/m2, respectively. The mFOLFIRINOX 5-FU dose was 2400 mg/m2 over 46 hours (no bolus) with leucovorin 400 mg/m2, and oxaliplatin 85 mg/m2. Outcomes included ORR, tolerability/safety, mPFS, and mOS for both trials. Results: In the pooled analysis, 18 pts with GEC were enrolled to date (11 at WU and 7 at UC), and 16 evaluable for response. ORR was 62.5% (10/16), (HER2- 58% (7/12), HER2+ 75% (3/4)). One HER2+ pt experienced a CR. mPFS was 8 months (range 1.5-18 months), however 10/16 pts have not progressed on first-line therapy to date. There were no unexpected toxicities for any of the regimens. Conclusions: ORR and PFS with first-line FOLFIRINOX were encouraging for metastatic GEC. sFOLFIRINOX was well tolerated in these patients, and sFOLFIRINOX-T was safely administered.mFOLFIRINOX consisting of genotype-directed irinotecan dose reductions and no 5FU bolus may limit toxicity yet retain similar benefit to sFOLFIRINOX. Continued investigation of this regimen is warranted given these encouraging preliminary results. Clinical trial information: 01928290.

Phase II trial of levocetirizine with capecitabine and bevacizumab to overcome the resistance of antiangiogenic therapies in refractory metastatic colorectal cancer

763

Background: Despite clinical success of VEGF blockade in mCRC, resistance to anti-angiogenic drugs invariably develops. IL-8 and other cytokines have been implicated in resistance development to anti-angiogenic therapy. Levocetirizine is a third generation antihistamine with anti-inflammatory and IL-8 suppression properties. We conducted a phase II trial combining levocetirizine with capecitabine and bevacizumab to potentially overcome anti-angiogenic therapy resistance in patients with refractory mCRC. Methods: This was a single-center open-label prospective trial in refractory mCRC patients. Treatment consisted of oral capecitabine 850mg/m2 – 7 days on and 7 days off, IV bevacizumab 5 mg/kg every 14 days and oral levocetirizine 5 mg daily in 14 day cycles. The primary end point was PFS and secondary endpoints included ORR and tolerability. An exploratory endpoint included correlation of PFS with cytokine (IL-8 & IL-6) levels. A sample size of 36 evaluable patients could identify a median PFS of 3.4 months at a 0.05 significance level. To document cytokine changes related to levocetirizine treatment, patients were randomized to Arm A where levocetirizine was started 7 days after starting chemotherapy or to Arm B where levocetirizine was started 7 days prior to chemotherapy. For PFS determination both arms were combined for analysis. Cytokine levels were measured at baseline and with each cycle of chemotherapy (up to three cycles). Results: 43 patients were enrolled in the trial to have 36 evaluable patients. Arm A enrolled 20 patients and Arm B enrolled 23 patients. Of the patients evaluable for best response, 19 had SD and 12 had PD. Median PFS of all patients on the study was 3.4 months (ranging 0.9 to 10.6 months). Conclusions: Median PFS in the trial was comparable to and possibly better than other regimens used in the refractory setting (e.g., median PFS of 1.9 months for regorafenib). Cytokine analysis is in progress and these results and correlations with patient outcomes will be presented to assess the impact of cytokine blockade on mCRC treatment. Clinical trial information: NCT01722162.

Phase IB study of FOLFIRINOX plus PF-04136309 in patients with borderline resectable and locally advanced pancreatic adenocarcinoma (PC)

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Background: PF-04136309 (a novel CCR2 inhibitor) has shown anti-tumor activity in the preclinical setting in PC by depleting inflammatory monocytes and tumor associated macrophages (TAM) that contribute to an immunosuppressive tumor microenvironment. We hypothesized that combining PF-04136309 with FOLFIRINOX may improve clinical outcomes in PC. Methods: This is a phase Ib study with a dose de-escalation schema given the minimal toxicity of PF-04136309. The study includes Arm A (FOLFIRINOX only), Arm B (FOLFIRINOX plus PF-04136309) and an expansion cohort at the rapid phase II dose (RP2D). FOLFIRINOX (oxaliplatin 85 mg/m2, irinotecan 180 mg/m2, LV 400 mg/m2, 5FU bolus 400 mg/m2 and 2,400 mg/m2over 46 hours) was administered every two weeks. PF-04136309 at 500 mg twice daily via oral route was the starting dose level for Arm B. Treatment response was assessed after 6 cycles of treatment. Bone marrow biopsy and EUS/FNA at baseline and post 2 cycles were performed to assess the impact of treatment on the prevalence and function of inflammatory monocytes in the blood, bone marrow and tumor. Results: A total of 41 patients have been enrolled in the study to date (6 in Arm A, 8 in Arm B and 27 in the expansion cohort). The mean age of patients was 61.1 (range 45-75 yrs), male/female: 21/20, Caucasian/others: 32/9, borderline/locally advanced: 7/34. PF-04136309 at the starting dose did not result in additional toxicities when combined with FOLFIRINOX and it is the RP2D. Out of 35 patients treated with FOLFIRINOX plus PF-04136309, 6 are still in treatment, 6 are non-evaluable (withdrew consent or had poor tolerance). Of the 23 evaluable patients, 21 (91.3%) completed all 6 cycles; 12 (52.2%) had PR by RECIST and 11 (47.8%) had SD. Curative resections were achieved in 4 out of 5 with borderline resectable and 2 with locally advanced PC. Moreover, blockade of TAM mobilization was demonstrated by FACS and qPCR analysis of baseline and post-treatment FNA biopsies. Conclusions: Combing PF-04136309 with FOLFIRINOX is safe and tolerable. The regimen resulted in impressive treatment response and it further validated CCR2 inhibition in PC. Survival data and more correlative science will be forthcoming. Clinical trial information: 01413022.

Prevalence, awareness, treatment and control of diabetes mellitus among the elderly: The 2011 National Health and Morbidity Survey, Malaysia

Diabetes mellitus is an important cardiovascular risk factor. The objective of this study was to provide population-based estimates on the prevalence, awareness, treatment and control rate of diabetes among the older persons in Malaysia. Analysis of secondary data from a cross-sectional national population-based survey was done, which was conducted in 2011 throughout Malaysia. A total of 2764 respondents (15.5%) were older persons. The overall prevalence of diabetes among older persons was 34.4% in which 65.2% were aware of their diabetes status. Out of those who were aware, 87.5% had been treated. Only 21.8% of those treated had their diabetes controlled. The results of multiple logistic regression showed that the factors associated with higher awareness rates were women, Indians and higher income groups; factors associated with higher treatment rates were urban residents and those who were married and widow/widower/ divorcee. There was a high overall prevalence, awareness and treatment rate of diabetes among older persons in Malaysia but with suboptimal control rate.

Duplication of the vermiform appendix in an adult patient

Duplication of the appendix is extremely rare. A 69-year-old woman was admitted with a 2-day history of right lower quadrant abdominal pain. Physical examination was consistent with acute appendicitis. Ultrasonography and colonoscopy gave a clinical impression of an inflammatory appendiceal mucocoele. Operative findings were an enlarged and inflamed appendix with distal cystic changes. Laparoscopic wedge resection of the caecum was performed. A tubular structure with a true lumen was found in the appendix. Haematoxylin and eosin staining and trichrome staining showed both structures had a true mucosa and a muscular layer. The duplication in this case does not belong to any of the previously described types of duplication.

The prevalence of physical activity and its associated factors among Malaysian adults: findings from the National Health and Morbidity Survey 2011

OBJECTIVES

Despite the health-enhancing benefits of physical activity, a large segment of the Malaysian population does not engage in regular physical activity at the recommended level. This study aimed to determine physical activity patterns and the associated sociodemographic correlates of physical activity.

STUDY DESIGN

Data on physical activity were obtained from the National Health and Morbidity Survey (NHMS) 2011, a nationally representative, population-based cross-sectional study. A two-stage stratified sampling method was used to select a representative sample of Malaysian adults aged 16 years and above.

METHODS

A total of 19,145 adults aged 16 years and above were recruited, and face-to-face interviews were conducted using the International Physical Activity Questionnaire (IPAQ), short version. The correlates for physical activity were identified using multivariate analysis.

RESULTS

In this study, 64.3% (95%CI: 63.1-65.5) of Malaysian adults aged 16 and above were physically active, but overall physical activity levels decreased with advancing age. Men, rural residents, 'other' ethnic groups, and married women were more likely to demonstrate higher levels of physical activity.

CONCLUSION

Approximately 65% of Malaysian adults were physically active. However, it is recommended that health promotions for active lifestyles should be targeted to the least active segments, which constitute more than a quarter of the Malaysian population.

Abstract 4543: High-throughput combination screening identifies novel drug-drug pairings for a Bruton's tyrosine kinase inhibitor against the ABC subtype of diffuse large B-cell lymphomas

The vast majority of cancer treatments currently administered to patients consist of combinations of more than one drug via routine infusions that adhere to specific dosing schedules. It is thought that this multi-arm and time dependent approach will kill not only the tumor cells within the primary site, but also any metastatic lesions, and importantly, any circulating tumor cells (CTCs) which may still exist in the blood. Combination therapies have also been developed as a means to reduce general cytotoxic side effects and prevent resistance and recurrence. Our labs have recently developed a high throughput screening platform to test compounds in pair-wise combinations to rapidly and systematically identify additive, synergistic and antagonistic drug combinations. This HTS capability can easily generate hundreds of dose response matrices in a single study and can increase significantly when applied to multiple cell lines. We are using this combination screening platform with in vitro models from both established cell lines and primary patient material, and we expect it will serve as a very valuable tool and a starting point when designing clinical trials after these combinations show promise within in vivo models. In a proof of concept study, we tested combinations of compounds that effectively kill 2 established lines of the ABC sub-type of diffuse large B-cell lymphoma (DLBCL); TMD8 and HBL1. We will present the infrastructure and methods that we have developed to implement the combination screens, visualize data from the combination dose response comparisons and numerically compare combinations in terms of their response matrices. We will also describe how this approach allows us to investigate putative polypharmacological effects that play a role in compound combination responses. Finally, we will show the results of a combination screen with TMD8 and HBL1 cells, including the identification of a novel drug-drug combination for the BTK inhibitor ibrutinib (PCI-32765) which is of both basic and translational interest for the treatment of DLBCL.

Citation Format: Lesley A. Mathews, Rajarshi Guha, Paul Shinn, Ryan M. Young, Kian-Huat Lim, Jonathan Keller, Dongbo Liu, Adam Yasgar, Crystal McKnight, Matthew B. Boxer, Damien Y. Duveau, Jian-kang Jiang, Sam Michael, Bryan T. Mott, Paresma R. Patel, William Leister, David J. Maloney, Christopher A. LeClair, Ganesha Rai, Ajit Jadhav, Brian D. Peyser, Christopher P. Austin, Scott Martin, Anton Simeonov, Marc Ferrer, Louis Staudt, Craig J. Thomas. High-throughput combination screening identifies novel drug-drug pairings for a Bruton's tyrosine kinase inhibitor against the ABC subtype of diffuse large B-cell lymphomas. [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 4543. doi:10.1158/1538-7445.AM2013-4543