Citations

176 Background: Multiple tumour tissue studies have demonstrated the prognostic utility of CNVs in mCRPC. However, accurate assessment of CNVs in plasma cfDNA remains challenging, and prognostic significance has not been well characterized. Using a large customized panel, we correlated plasma CNVs with clinical outcomes in a contemporary cohort of mCRPC patients. Methods: Deep targeted sequencing was performed using a 180-gene cfDNA panel (Predicine) in 56 patients commencing AR pathway inhibitors (enzalutamide or abiraterone; n = 34) or taxane chemotherapy (n = 22) at two Australian institutions. Kaplan-Meier estimates and Cox proportional-hazards models were used to correlate CNVs with progression-free survival (PFS) and overall survival (OS). Significant results were validated in an independent cohort (Mayo Clinic, n = 144). Results: Median follow-up was 19.4 months (mo; IQR 11.3-31.9). The most common CNVs in the Australian cohort are shown (Table). OS was significantly decreased in patients with PI3KCA gain (median 21.7 mo vs 6.6 mo, p < 0.0001), PTEN loss (24.8 mo vs 11.7 mo, p = 0.0019) and AR gain (21.7 mo vs 12.0 mo, p = 0.0083). Furthermore, all three alterations independently predicted for poor survival in multivariable analyses (MVA; Table). Findings in the independent cohort showed similar OS results in MVA: PIK3CA gain (HR 2.0, p = 0.07), PTEN loss (HR 1.7, p = 0.08) and AR gain (HR 1.7, p = 0.03). Conclusions: Sequencing of plasma cfDNA revealed that PTEN loss, and PIK3CA and AR gain are associated with inferior clinical outcomes in patients commencing contemporary systemic treatment. These data support therapeutic strategies co-targeting the PI3K and AR pathways in mCRPC.[Table: see text]

Abstract Background: Absolute lymphocyte count (ALC) recovery is an independent prognostic factor for survival for different hematological malignancies treated with autologous stem cell transplantation. Recently, we reported superior overall survival (OS) in patients with follicular lymphomas that presented with a higher ALC (ALC ≥ 1 x 109/L) at diagnosis. The role of ALC at diagnosis on survival in T cell lymphomas is not known. Methods: All patients evaluated at the Mayo Clinic for T cell lymphomas from October 1984 until April 2005 were analyzed in the study. The primary objective of the study was to assess the role of ALC at diagnosis and survival in T cell lymphomas. ALC at diagnosis was obtained from the standard complete blood cell count (CBC). Results: 223 patients with T cell lymphomas were included in the study. The histology included: peripheral T-cell lymphoma-unspecified (40%), anaplastic large cell (13%), angioimmunoblastic (10%), angiocentric (4%), intestinal T-cell (2%), and other (31%). The median follow-up was 18.6 months (range: 1 month – 229 months [19 years]). The sample population included 60% male and 40% females with a median age of 60 years (15–90 years). The median ALC at diagnosis was 1.2 x 109/L (range: 0.04–6.7 x 109/L). ALC as a continuous variable was identified as predictor for OS in the univariate analysis (HR= 0.690, 95%CI: 0.542–0.862, p < 0.0006). ALC ≥ 1 x 109/L was selected as the dichotomized value because it yielded the maximum difference in survival by c2 analysis looking at different cut-point from 0.6 to 1.7 x 109/L that were included between the 25% and 75% quartiles. Univariately, ALC ≥ 1 x 109/L was also identified as a predictor for OS (HR = 0.682, 95%CL= 0.578–0.804, p < 0.0001). Patients (N = 122) with an ALC ≥ 1 x 109/L experienced superior survival compared to patients (N = 101) with an ALC < 1 x 109/L [median OS: 76.3 vs 10.6 months, respectively; and 5 years OS estimates of 53% vs 23%, respectively, p < 0.0001]. When ALC ≥ 1 x 109/L was compared to the international prognostic index (IPI), ALC ≥ 1 x 109/L remained an independent predictor for survival in the multivariate analysis (HR = 0.779, 95%CL: 0.655–0.925, p < 0.004). Conclusion: This study demonstrates ALC as an independent predictor for OS in T cell lymphomas, suggesting that the host immune system affects survival in this group of patients.

In mouse models of biliary tract diseases, macrophages are recruited to the periductal milieu and promote injury and cholestasis. Although cell necrosis with release of biomolecules termed damage-associated molecular patterns (DAMPs) promotes recruitment and activation of macrophages, necrosis was not observed in these studies. Because extracellular vesicles (EVs) are important in cell-to-cell communication, we postulated that activated cholangiocytes may release EVs containing DAMPs as cargo. Both the human (NHC) and mouse cholangiocyte (603B) cell lines display constitutive activation with mRNA expression of chemokines. Proteomic analysis revealed that EVs from both cell lines contained the DAMP S100A11, a ligand for the receptor for advanced glycation end products (RAGE). Bone marrow-derived macrophages (BMDM) incubated with EVs derived from the mouse 603B cell line increased mRNA expression of proinflammatory cytokines. Genetic or pharmacologic inhibition of RAGE reduced BMDM expression of proinflammatory cytokines treated with EVs. RAGE signaling resulted in activation of the canonical NF-κB pathway, and consistently, proinflammatory cytokine expression was blunted by the IKKα/β inhibitor TPCA-1 in BMDM incubated with EVs. We also demonstrated that primary mouse cholangiocyte-derived organoids express chemokines indicating cholangiocyte activation, release EVs containing S100A11, and stimulate proinflammatory cytokine expression in BMDM by a RAGE-dependent pathway. In conclusion, these observations identify a non-cell death mechanism for cellular release of DAMPs by activated cholangiocytes, namely by releasing DAMPs as EV cargo. These data also suggest RAGE inhibitors may be salutary in macrophage-associated inflammatory diseases of the bile ducts.

Abstract Background: Whether associations between circulating metabolites and prostate cancer are causal is unknown. We report on the largest study of metabolites and prostate cancer (2,291 cases and 2,661 controls) and appraise causality for a subset of the prostate cancer–metabolite associations using two-sample Mendelian randomization (MR). Methods: The case–control portion of the study was conducted in nine UK centers with men ages 50–69 years who underwent prostate-specific antigen screening for prostate cancer within the Prostate Testing for Cancer and Treatment (ProtecT) trial. Two data sources were used to appraise causality: a genome-wide association study (GWAS) of metabolites in 24,925 participants and a GWAS of prostate cancer in 44,825 cases and 27,904 controls within the Association Group to Investigate Cancer Associated Alterations in the Genome (PRACTICAL) consortium. Results: Thirty-five metabolites were strongly associated with prostate cancer (P &lt; 0.0014, multiple-testing threshold). These fell into four classes: (i) lipids and lipoprotein subclass characteristics (total cholesterol and ratios, cholesterol esters and ratios, free cholesterol and ratios, phospholipids and ratios, and triglyceride ratios); (ii) fatty acids and ratios; (iii) amino acids; (iv) and fluid balance. Fourteen top metabolites were proxied by genetic variables, but MR indicated these were not causal. Conclusions: We identified 35 circulating metabolites associated with prostate cancer presence, but found no evidence of causality for those 14 testable with MR. Thus, the 14 MR-tested metabolites are unlikely to be mechanistically important in prostate cancer risk. Impact: The metabolome provides a promising set of biomarkers that may aid prostate cancer classification.

475 Background: The vascular disrupting agent (VDA) BNC105P shows synergy with everolimus in preclinical models. The DisrupTOR-1 trial included a phase I component exploring this combination and a randomized phase II component comparing everolimus with BNC105P (Arm A) to everolimus monotherapy (Arm B) (Pal et al. ESMO 2014). Methods: Pts with clear cell mRCC and 1-2 prior therapies (including ≥1 VEGF-TKI) were randomized in the phase II study component. In Arm A, patients received a 7 day lead-in dose of everolimus followed by dosing with BNC105P. Patients in Arm A had optional blood collections prior to administration of BNC105P and 3 hours after receiving BNC105P. A fluorescence-based assay was used to characterize a broad panel of analytes at each time point. Biomarkers were assessed in both a static and dynamic fashion. For the former, biomarkers were stratified by median value, and progression-free survival (PFS) was compared in resulting subgroups using the Kaplan-Meier method. For the latter, change in biomarker level before and after BNC105P infusion was stratified by median difference, and PFS was compared in resulting subgroups using the Kaplan-Meier method. Results: 139 pts were randomized with 69 and 67 evaluable pts in Arms A and B, respectively. Dynamic biomarkers were assessed in a total of 44 patients who received everolimus with BNC105P. Increases in matrix metalloproteinase-9 (MMP-9) and stem cell factor (SCF) were associated with improved PFS (p=0.0421 and p=0.0291, respectively). Decreases in sex hormone binding globulin (SHBG) and serum amyloid protein (SAP) were associated with improved PFS (p=0.0184 and p=0.0063). With respect to static biomarkers, elevated baseline ferritin and lower baseline IL-8 were associated with improved PFS (p=0.0291 and p=0.0149, respectively). Conclusions: Several static and dynamic biomarkers in the DisrupTOR-1 trial were associated with PFS. A prospective biomarker-driven study examining everolimus with BNC105P selected by baseline IL-8 and ferritin is in development. Clinical trial information: NCT01034631.

Abstract Purpose: BNC105P inhibits tubulin polymerization, and preclinical studies suggest possible synergy with everolimus. In this phase I/II study, efficacy and safety of the combination were explored in patients with metastatic renal cell carcinoma (mRCC). Experimental Design: A phase I study in patients with clear cell mRCC and any prior number of therapies was conducted using a classical 3 + 3 design to evaluate standard doses of everolimus with increasing doses of BNC105P. At the recommended phase II dose (RP2D), patients with clear cell mRCC and one to two prior therapies (including ≥ 1 VEGF-TKI) were randomized to BNC105P with everolimus (arm A) or everolimus alone (arm B). The primary endpoint of the study was 6-month progression-free survival (6MPFS). Secondary endpoints included response rate, PFS, overall survival, and exploratory biomarker analyses. Results: In the phase I study (N = 15), a dose of BNC105P at 16 mg/m2 with everolimus at 10 mg daily was identified as the RP2D. In the phase II study, 139 patients were randomized, with 69 and 67 evaluable patients in arms A and B, respectively. 6MPFS was similar in the treatment arms (arm A: 33.82% vs. arm B: 30.30%, P = 0.66) and no difference in median PFS was observed (arm A: 4.7 mos vs. arm B: 4.1 mos; P = 0.49). Changes in matrix metalloproteinase-9, stem cell factor, sex hormone-binding globulin, and serum amyloid A protein were associated with clinical outcome with BNC105P. Conclusions: Although the primary endpoint was not met in an unselected population, correlative studies suggest several biomarkers that warrant further prospective evaluation. Clin Cancer Res; 21(15); 3420–7. ©2015 AACR.