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There is a dire need for better visualization of cancer and analysis of specific targets in vivo. Molecular imaging with fluorescence is gaining more and more attention, as it allows detection of these targets and has advantages over radioactivity, such as no radiation dose, and lower costs. A key challenge in optical imaging however, is translation of the newly developed tracers from pre-clinical phase to clinical application. We describe the development and safety testing of clinical grade bevacizumab-800CW, an antibody-based targeted agent for non-invasive imaging of vascular endothelial growth factor A (VEGF-A).Development included implementing the manufacturing process and analytical methods according to current Good Manufacturing Practice (cGMP), formulation studies, extended characterization and stability testing. For safety pharmacology an extended single dose toxicity study in mice was performed.Bevacizumab-800CW was formulated in isotonic phosphate buffered sodium chloride solution at pH 7. The production was robust and showed a reproducible labeling efficiency, and no impurities. The binding affinity to VEGF-A remained intact. The optimized product meets all release specifications, is stable up to at least 3 months and its characteristics did not significantly differ from the unlabeled bevacizumab. Toxicity testing in mice showed no remarkable findings.In conclusion, sterile bevacizumab-800CW (6 mg = 6 ml) can be produced in stock according to current Good Manufacturing Practice. It is ready for first-in-human use. (C) 2016 Elsevier B.V. All rights reserved.

DMOT4039A, a humanized anti-mesothelin mAb conjugated to the antimitotic agent monomethyl auristatin E (MMAE), was given to patients with pancreatic and ovarian cancer every 3 weeks (0.2–2.8 mg/kg; q3w) or weekly (0.8–1.2 mg/kg). A 3+3 design was used for dose escalation followed by expansion at the recommended phase II dose (RP2D) to evaluate safety and pharmacokinetics. Antitumor response was evaluated per RECIST 1.1 and serum CA19-9 or CA125 declines. Tumor mesothelin expression was determined by IHC. Seventy-one patients (40 pancreatic cancer; 31 ovarian cancer) were treated with DMOT4039A. For the q3w schedule (n = 54), the MTD and RP2D was 2.4 mg/kg, with dose-limiting toxicities of grade 3 hyperglycemia and grade 3 hypophosphatemia at 2.8 mg/kg. For the weekly schedule (n = 17), the maximum assessed dose was 1.2 mg/kg, with further dose escalations deferred because of toxicities limiting scheduled retreatment in later cycles, and therefore the RP2D level for the weekly regimen was determined to be 1 mg/kg. Across both schedules, the most common toxicities were gastrointestinal and constitutional. Treatment-related serious adverse events occurred in 6 patients; 4 patients continued treatment following dose reductions. Drug exposure as measured by antibody-conjugated MMAE and total antibody was generally dose proportional over all dose levels on both schedules. A total of 6 patients had confirmed partial responses (4 ovarian; 2 pancreatic) with DMOT4039A at 2.4 to 2.8 mg/kg i.v. q3w. DMOT4039A administered at doses up to 2.4 mg/kg q3w and 1.0 mg/kg weekly has a tolerable safety profile and antitumor activity in both pancreatic and ovarian cancer. Mol Cancer Ther; 15(3); 439–47. ©2016 AACR.

AMG 110, a bispecific T cell engager (BITE) antibody construct, induces T cell-mediated cancer cell death by cross-linking epithelial cell adhesion molecule (EpCAM) on tumor cells with a cluster of differentiation 3 epsilon (CD3 epsilon) on T cells. We labeled AMG 110 with Zr-89 or near infrared fluorescent dye (IRDye) 800CW to study its tumor targeting and tissue distribution. Methods: Biodistribution and tumor uptake of Zr-89-AMG 110 was studied up to 6 d after intravenous administration to nude BALB/c mice bearing high EpCAM-expressing HT-29 colorectal cancer xenografts. Tumor uptake of Zr-89-AMG 110 was compared with uptake in head and neck squamous cell cancer FaDu (intermediate EpCAM) and promyelocytic leukemia HL60 (EpCAM-negative) xenografts. Intratumoral distribution in HT-29 tumors was studied using 800CW-AMG 110. Results: Tumor uptake of Zr-89-AMG 110 can be clearly visualized using small-animal PET imaging up to 72 h after injection. The highest tumor uptake of Zr-89-AMG 110 at the 40-mu g dose level was observed at 6 and 24 h (respectively, 5.35 +/- 0.22 and 5.30 +/- 0.20 percentage injected dose per gram; n = 3 and 4). Tumor uptake of Zr-89-AMG 110 was EpCAM-specific and correlated with EpCAM expression. 800CW-AMG 110 accumulated at the tumor cell surface in viable EpCAM-expressing tumor tissue. Conclusion: PET and fluorescent imaging provided real-time information about AMG 110 distribution and tumor uptake in vivo. Our data support using Zr-89 and IRDye 800CW to evaluate tumor and tissue uptake kinetics of bispecific T cell engager antibody constructs in preclinical and clinical settings.

Every year, cervical cancer affects similar to 500,000 women worldwide, and similar to 275,000 patients die of this disease. The addition of platin-based chemotherapy to primary radiotherapy has increased 5-year survival of advanced-stage cervical cancer patients, which is, however, still only 66%. One of the factors thought to contribute to treatment failure is the ability of tumor cells to repair chemoradiotherapy-induced DNA damage. Therefore, sensitization of tumor cells for chemoradiotherapy via inhibition of the DNA damage response (DDR) as a novel strategy to improve therapy effect, is currently studied pre-clinically as well as in the clinic. Almost invariably, cervical carcinogenesis involves infection with the human papillomavirus (HPV), which inactivates part of the DNA damage response. This HPV-mediated partial inactivation of the DDR presents therapeutic targeting of the residual DDR as an interesting approach to achieve chemoradio-sensitization for cervical cancer. How the DDR can be most efficiently targeted, however, remains unclear. The fact that cisplatin and radiotherapy activate multiple signaling axes within the DDR further complicates a rational choice of therapeutic targets within the DDR. In this review, we provide an overview of the current preclinical and clinical knowledge about targeting the DDR in cervical cancer. (C) 2015 Elsevier Ltd. All rights reserved.

BackgroundTo better predict response to immune checkpoint therapy and toxicity in healthy tissues, insight in the in vivo behavior of immune checkpoint targeting monoclonal antibodies is essential. Therefore, we aimed to study in vivo pharmacokinetics and whole-body distribution of zirconium-89 (89Zr) labeled programmed cell death protein-1 (PD-1) targeting pembrolizumab with positron-emission tomography (PET) in humanized mice.MethodsHumanized (huNOG) and non-humanized NOG mice were xenografted with human A375M melanoma cells. PET imaging was performed on day 7 post 89Zr-pembrolizumab (10 µg, 2.5 MBq) administration, followed by ex vivo biodistribution studies. Other huNOG mice bearing A375M tumors received a co-injection of excess (90 µg) unlabeled pembrolizumab or 89Zr-IgG4 control (10 µg, 2.5 MBq). Tumor and spleen tissue were studied with autoradiography and immunohistochemically including PD-1.ResultsPET imaging and biodistribution studies showed high 89Zr-pembrolizumab uptake in tissues containing human immune cells, including spleen, lymph nodes and bone marrow. Tumor uptake of 89Zr-pembrolizumab was lower than uptake in lymphoid tissues, but higher than uptake in other organs. High uptake in lymphoid tissues could be reduced by excess unlabeled pembrolizumab. Tracer activity in blood pool was increased by addition of unlabeled pembrolizumab, but tumor uptake was not affected. Autoradiography supported PET findings and immunohistochemical staining on spleen and lymph node tissue showed PD-1 positive cells, whereas tumor tissue was PD-1 negative.Conclusion89Zr-pembrolizumab whole-body biodistribution showed high PD-1-mediated uptake in lymphoid tissues, such as spleen, lymph nodes and bone marrow, and modest tumor uptake. Our data may enable evaluation of 89Zr-pembrolizumab whole-body distribution in patients.

Background: ER+ metastatic breast cancer (mBC) remains a clinical challenge as most patients (pts) eventually have disease progression on treatment (tx). Multiple molecular mechanisms of resistance to standard-of-care drugs have been reported including mutations in ESR1 (mESR1) or PIK3CA (mPIK3CA); understanding how these affect response to subsequent tx is important. Elacestrant (RAD1901), an investigational oral selective estrogen receptor degrader (SERD), has demonstrated preclinical efficacy in pt-derived xenograft models of ER+ BC, including models harboring mESR1 and mPIK3CA. Elacestrant was evaluated in 2 phase 1 clinical trials (NCT02650817, NCT02338349) in postmenopausal women with ER+/HER2- mBC, including pts that had received multiple prior endocrine tx (median=3) and targeted tx, including CDK4/6 inhibitors (38%). Circulating tumor DNA (ctDNA) collected in these 2 trials was used to characterize the molecular features of this heavily pretreated population and correlate them with elacestrant response. Methods: ctDNA samples were collected at baseline (BL), on-tx (OT) and end-of-tx (EOT). BL samples were analyzed using the Guardant360® assay (Guardant Health) to detect genomic alterations in 73 relevant genes. Changes in BL mESR1 allele frequency of 12 single nucleotide variants (SNVs) in the ligand binding domain of ESR1 were assessed in paired OT and EOT ctDNA samples using the OncoBEAM™ platform (Sysmex Inostics). Response was assessed using RECIST v1.1. Results: Among 73 pts enrolled in these 2 trials, 57 had BL samples. At least 1 alteration was detected in 93% (n=53) of pt samples, with alterations detected in 52 of the 73 genes in the Guardant360® panel. The most frequently detected BL alterations were in ESR1 (47%) and PIK3CA (44%), with alterations in both genes observed in 21% of pts. At BL, 25% (14/57) of pt samples had >1 mESR1; the most commonly detected mESR1 were Y537S (56%), D538G (56%), and Y537N (26%). Following elacestrant tx, there was a decrease in mESR1 allele frequency in 100% of samples (11/11 mESR1 SNVs decreased OT in 9/9 pts). In paired EOT samples from pts lacking mESR1 at BL analyzed to date (N=23), 1 new mESR1 was detected in 1 pt. Among response-evaluable (RE) pts with mESR1 at BL (n=16), there were 4 partial responses (PR; 25%); clinical benefit rate (CBR) at 24 weeks (ie, stable disease + PR) in clinical benefit evaluable (CBE) pts was 52% (11/21); and median progression-free survival (mPFS) in intention-to-treat (ITT) pts was 8.6 mo. Among RE pts with mPIK3CA at BL (n=16), there were 2 PRs (13%); CBR at 24 weeks in CBE pts was 24% (5/21); and mPFS (ITT pts) was 1.9 mo. Conclusions: Relevant genomic alterations, especially in ESR1 and PI3KCA, were detected at BL in a significant proportion of heavily pretreated postmenopausal women with ER+/HER2- mBC enrolled in elacestrant phase 1 trials. Clinical benefit, including PR, was observed in pts with genomic alterations, including mESR1 and PIK3CA. Elacestrant monotherapy vs. standard of care endocrine tx is currently being studied in the phase 3 “EMERALD” study in ER+/HER2- mBC pts, including pts with mESR1, who have received 1 or 2 prior lines of endocrine tx and prior CDK4/6i (NCT03778931). Citation Format: Teeru Bihani, JungAh Jung, Hitisha K Patel, Aditya Bardia, Peter Kabos, Virginia Kaklamani, Agnes Jager, Philippe Aftimos, Sharon Wilks, Elisabeth de Vries, Wael Harb, Donald Richards, Amy Weise, Robert Wesolowski, Catharina CW Menke-van der Houven van Oordt, Paul Conkling, Patrick Neven, Maureen G Conlan. Genomic alterations detected by circulating tumor DNA and correlation with response to treatment with elacestrant, an oral selective estrogen receptor degrader, in phase 1 trials in postmenopausal women with ER+/HER2- advanced/metastatic breast cancer [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr P5-01-05.

Background Metastatic melanoma patients can have durable responses to systemic therapy and even long-term survival. However, a large subgroup of patients does not benefit. Tumour metabolic alterations may well be involved in the efficacy of both targeted and immunotherapy. Knowledge on in vivo tumour glucose uptake and its heterogeneity in metastatic melanoma may aid in upfront patient selection for novel (concomitant) metabolically targeted therapies. The aim of this retrospective study was to provide insight into quantitative 18F-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) parameters and corresponding intra- and inter-patient heterogeneity in tumour 18F-FDG uptake among metastatic melanoma patients. Consecutive, newly diagnosed stage IV melanoma patients with a baseline 18F-FDG PET/CT scan performed between May 2014 and December 2015 and scheduled to start first-line systemic treatment were included. Volume of interests (VOIs) of all visible tumour lesions were delineated using a gradient-based contour method, and standardized uptake values (SUVs), metabolically active tumour volume (MATV) and total lesion glycolysis (TLG) were determined on a per-lesion and per-patient basis. Differences in quantitative PET parameters were explored between patient categories stratified by BRAFV600 and RAS mutational status, baseline serum lactate dehydrogenase (LDH) levels and tumour programmed death-ligand 1 (PD-L1) expression. Results In 64 patients, 1143 lesions ≥ 1 ml were delineated. Median number of lesions ≥ 1 ml was 6 (range 0–168), median maximum SUVpeak 9.5 (range 0–58), median total MATV 29 ml (range 0–2212) and median total TLG 209 (range 0–16,740). Per-patient analysis revealed considerable intra- and inter-patient heterogeneity. Maximum SUVs, MATV, number of lesions and TLG per patient did not differ when stratifying between BRAFV600 or RAS mutational status or PD-L1 expression status, but were higher in the patient group with elevated LDH levels (> 250 U/l) compared to the group with normal LDH levels (P

Glypican 3 (GPC3), a membrane-bound heparan sulfate proteoglycan, is overexpressed in approximately 70% to 80% of hepatocellular carcinomas, but is not expressed commonly in healthy tissues. This raised interest in GPC3 as a drug target and several GPC3-targeting drugs are in clinical development. We therefore predicted GPC3 protein overexpression across tumors and validated these predictions. Functional genomic mRNA profiling was applied to the expression profiles of 18,055 patient-derived tumor samples to predict GPC3 overexpression at the protein level in 60 tumor types and subtypes using healthy tissues as reference. For validation, predictions were compared with immunohistochemical (IHC) staining of a breast cancer tissue microarray and literature data reporting IHC GPC3 overexpression in various solid, hematologic, and pediatric tumors. The percentage of samples with predicted GPC3 overexpression was 77% for hepatocellular carcinomas (n = 364), 45% for squamous cell lung cancers (n = 405), and 19% for head and neck squamous cell cancers (n = 344). Breast cancer tissue microarray analysis showed GPC3 expression ranged from 12% to 17% in subgroups based on estrogen receptor and human epidermal growth factor receptor 2 status. In 28 of 34 tumor types for which functional genomic mRNA data could be compared with IHC there was a relative difference of ≤10%. This study provides a data-driven prioritization of tumor types and subtypes for future research with GPC3-targeting therapies.

Purpose: AMG 211, a bispecific T-cell engager (BiTE) antibody construct, targets carcinoembryonic antigen (CEA) and the CD3 epsilon subunit of the human T-cell receptor. AMG 211 was labeled with zirconium-89 (89Zr) or fluorescent dye to evaluate the tumor-targeting properties. Experimental Design: 89Zr-AMG211 was administered to mice bearing CEA-positive xenograft tumors of LS174T colorectal adenocarcinoma or BT474 breast cancer cells, as well as CEA-negative HL-60 promyelocytic leukemia xenografts. Biodistribution studies with 2- to 10-μg 89Zr-AMG211 supplemented with unlabeled AMG 211 up to 500-μg protein dose were performed. A BiTE that does not bind CEA, 89Zr-Mec14, served as a negative control. 89Zr-AMG211 integrity was determined in tumor lysates ex vivo. Intratumoral distribution was studied with IRDye800CW-AMG211. Moreover, 89Zr-AMG211 was manufactured according to Good Manufacturing Practice (GMP) guidelines for clinical trial NCT02760199. Results: 89Zr-AMG211 demonstrated dose-dependent tumor uptake at 6 hours. The highest tumor uptake was observed with a 2-μg dose, and the lowest tumor uptake was observed with a 500-μg dose. After 24 hours, higher uptake of 10-μg 89Zr-AMG211 occurred in CEA-positive xenografts, compared with CEA-negative xenografts. Although the blood half-life of 89Zr-AMG211 was approximately 1 hour, tumor retention persisted for at least 24 hours. 89Zr-Mec14 showed no tumor accumulation beyond background level. Ex vivo autoradiography revealed time-dependent disintegration of 89Zr-AMG211. 800CW-AMG211 was specifically localized in CEA-expressing viable tumor tissue. GMP-manufactured 89Zr-AMG211 fulfilled release specifications. Conclusions: 89Zr-AMG211 showed dose-dependent CEA-specific tumor targeting and localization in viable tumor tissue. Our data enabled its use to clinically evaluate AMG 211 in vivo behavior. Clin Cancer Res; 24(20); 4988–96. ©2018 AACR.

Cancer immunotherapy has led to impressive antitumor effects. However, not all patients respond to immunotherapy, serious toxicity can occur and combination therapy may be warranted. Strategies for rational early treatment choices are urgently required. In the absence of ideal accompanying biomarkers it remains challenging to capture the dynamic, heterogeneous and complex tumor behavior. Tumor immune response involves next to tumor cells, numerous other cells and molecules in the tumor microenvironment. We review research to identify potential novel imaging biomarkers by non-invasive whole body molecular imaging with positron emission tomography and single-photon emission computed tomography for cancer immunotherapy. Firstly, imaging with radiolabeled immune checkpoint targeting molecules. Secondly, imaging of immune cells with ex vivo or in vivo radiolabeled tracers and thirdly, imaging extracellular matrix components, including adhesion molecules, growth factors and cytokines. These molecular imaging strategies – used alone, in combination or serially – could potentially contribute to patient selection upfront or early during immunotherapy.

Introduction: Although targeting human epidermal growth factor receptor 2 (HER2) is a meaningful treatment in HER2-positive breast cancer, ultimately resistance develops. Androgen receptor (AR) expression and immune cell infiltration are thought to be involved in trastuzumab response and may, therefore, be of interest as additional targets for therapy in HER2-positive breast cancer.Aim: To improve insights into the presence among AR expression, immune cell infiltration and HER2, we analysed HER2-positive breast tumours.Methods: Primary tumours of 221 patients treated with trastuzumab for metastatic disease were selected. HER2 status was centrally confirmed. AR, T-cells (CD3 and CD8), programmed cell death protein 1 (PD-1) and PD-1 ligand 1 immunohistochemical staining and M2 tumour-associated macrophages (TAMs; CD68 and CD163) immunofluorescence were performed. Tumour-infiltrating lymphocytes were evaluated by haematoxylin and eosin staining.Results: Sufficient tumour material was available for 150 patients. Oestrogen receptor was expressed in 51.3% of the tumours andARin 81.3% of the tumours. AR expression was inversely correlated with M2 TAM (Pearson's r = -0.361, P Conclusion: AR expression inversely correlates with immune cell infiltration in HER2-positive breast cancer. (C) 2018 Elsevier Ltd. All rights reserved.

Purpose: Around 15%-30% of patients receiving breast-conserving surgery (BCS) for invasive breast carcinoma or ductal carcinoma in situ (DCIS) need a reoperation due to tumor-positive margins at final histopathology. Currently available intraoperative surgical margin assessment modalities all have specific limitations. Therefore, we aimed to assess the feasibility and accuracy of micro-computed tomography (micro-CT) as a novel method for intraoperative margin assessment in BCS.Methods: Lumpectomy specimens from 30 consecutive patients diagnosed with invasive breast cancer or DCIS were imaged using a micro-CT. Margin status was assessed on micro-CT images by two investigators who were blinded to the final histopathological margin status. The micro-CT margin status was compared with the histopathological margin status.Results: The margin status could be assessed by micro-CT in 29 out of 30 patients. Of these, nine patients had a positive tumor margin and 20 a negative tumor margin at final histopathology. Margin status evaluation by micro-CT took always less than 15 min. The margin status in 25 patients was correctly predicted by micro-CT. There were four false-negative predictions. The accuracy, sensitivity, specificity, positive predictive value and negative predictive value of micro-CT in margin status prediction were 86%, 56%, 100%, 100% and 83%, respectively. With micro-CT, the positive margin rate could potentially have been reduced from 31% to 14%.Conclusions: Whole lumpectomy specimen micro-CT scanning is a promising technique for intraoperative margin assessment in BCS. lntraoperative quick feedback on the margin status could potentially lead to a reduction in the number of reoperations. (C) 2018 Elsevier Ltd, BASO similar to The Association for Cancer Surgery, and the European Society of Surgical Oncology. All rights reserved.

Mesothelin is a tumor differentiation antigen expressed by epithelial tumors, including pancreatic cancer. Currently, mesothelin is being targeted with an antibodydrug conjugate (ADC) consisting of a mesothelin-specific antibody coupled to a highly potent chemotherapeutic drug. Considering the toxicity of the ADC and reduced accessibility of pancreatic tumors, non-invasive imaging could provide necessary information. We therefore developed a zirconium-89 (Zr-89) labeled anti-mesothelin antibody (Zr-89-AMA) to study its biodistribution in human pancreatic tumor bearing mice. Biodistribution and dose-finding of Zr-89-AMA were studied 144 h after tracer injection in mice with subcutaneously xenografted HPAC. MicroPET imaging was performed 24, 72 and 144 h after tracer injection in mice bearing HPAC or Capan-2. Tumor uptake and organ distribution of Zr-89-AMA were compared with nonspecific 111In-IgG. Biodistribution analyses revealed a dose-dependent Zr-89-AMA tumor uptake. Tumor uptake of Zr-89-AMA was higher than 111In-IgG using the lowest tracer dose. MicroPET showed increased tumor uptake over 6 days, whereas activity in blood pool and other tissues decreased. Immunohistochemistry showed that mesothelin was expressed by the HPAC and CAPAN-2 tumors and fluorescence microscopy revealed that AMA-800CW was present in tumor cell cytoplasm. Zr-89-AMA tumor uptake is antigen-specific in mesothelin-expressing tumors. Zr-89-AMA PET provides non-invasive, real-time information about AMA distribution and tumor targeting.

It is increasingly acknowledged that breast cancer can be an immunogenic disease. Immunogenicity appears to differ between subtypes. For instance, in triple negative breast cancer (TNBC) and HER2-positive breast cancer tumor infiltrating lymphocytes (TILs) are prognostic and predictive for response to chemotherapy containing anthracyclines, but in other subtypes they are not. Preclinical evidence suggests important immune based mechanisms of conventional chemotherapeutics, in particular anthracyclines. Early clinical studies with monoclonal antibodies targeting programmed death protein 1, programmed death-ligand 1 and cytotoxic T-lymphocyte-associated antigen 4 have shown anti-tumor efficacy. Tumor vaccines designed to increase the body's own anti-tumor immunity have shown an increased anti-tumor immunity, however clinical efficacy has not yet been demonstrated. Novel strategies will likely follow. In light of the increased interest in immune modulation, this review focuses on predictive immune-based biomarkers, immune-mediated effects from conventional therapies, as well as recent results and ongoing studies concerning immunotherapies in breast cancer. (C) 2015 Elsevier Inc. All rights reserved.

// Hilde H. Nienhuis 1,* , Marlous Arjaans 1,* , Hetty Timmer-Bosscha 1 , Elisabeth G.E. de Vries 1 and Carolina P. Schroder 1 1 Department of Medical Oncology, University of Groningen and University Medical, Center Groningen, Groningen, The Netherlands * These authors have contributed equally to this work Correspondence to: Carolina P. Schroder, email: // Keywords : breast cancer, microenvironment, zoledronic acid, TGF-β, CAM model Received : February 16, 2015 Accepted : May 30, 2015 Published : June 10, 2015 Abstract Previous studies suggested that bisphosphonate zoledronic acid exerts an anti-tumor effect by interacting with the microenvironment. In this study, we aimed to elucidate the mechanism behind the anti-breast cancer effect of zoledronic acid. Here we showed that zoledronic acid did not influence in vitro human breast cancer cell survival, but did affect human stromal cell survival. Breast cancer cell death in co-culture with stromal cells was analyzed in vitro by fluorescent microscopy and flowcytometry analysis. In co-culture, the addition of stromal cells to breast cancer cells induced tumor cell death by zoledronic acid, which was abolished by transforming growth factor (TGF)-β. In the in vivo chicken chorioallantoic membrane model, zoledronic acid reduced the breast cancer cells fraction per tumor only in the presence of human stromal cells. Zoledronic acid decreased TGF-β excretion by stromal cells and co-cultures. Moreover, supernatant of zoledronic acid treated stromal cells reduced phospho-Smad2 protein levels in breast cancer cells. Thus, zoledronic acid exerts an anti-breast cancer effect via stromal cells, accompanied by decreased stromal TGF-β excretion and reduced TGF-β signaling in cancer cells.

Background/Aims: Tryptophan is the precursor of serotonin and niacin (vitamin B3). The latter is critical for normal cellular metabolism. Tryptophan and niacin can be deficient in patients with serotonin-producing neuroendocrine tumors (NETs). Niacin deficiency may lead to severe symptoms including pellagra. In patients with serotonin-producing NET, data on niacin status are scarce and niacin supplementation hardly receives attention. We aimed to assess the niacin status before and after supplementation in these patients. Methods: We identified serotonin-producing NET patients who had received oral niacin supplementation (mean dose 144 mg daily) for tryptophan deficiency and/or pellagra-associated symptoms. Presupplementation plasma tryptophan levels and niacin status based on the urinary niacin metabolite N1-methylnicotinamide (N1-MN) before (n = 42) and after the start of the supplementation (in 34 paired samples) were assessed. Reference values for urinary N1-MN levels were established in 133 healthy individuals. Results: The mean presupplementation plasma tryptophan level was 31.8 ± 9.7 µmol/l (reference value 40.0-70.0). Presupplementation urinary N1-MN levels were lower in patients (median 17.9 µmol/24 h, range 2.6-70.3) compared to healthy controls (median 43.7 µmol/24 h, range 9.5-169.3, p < 0.0001) and below normal in 45% of the patients. Niacin supplementation increased urinary N1-MN levels to high normal levels (median 55.5 µmol/24 h, range 7.4-489.0) in 86% of the niacin-deficient patients. Conclusion: In serotonin-producing NET patients, niacin deficiency is prevalent. Therefore, urinary N1-MN deserves to be included in their standard biochemical evaluation. Niacin supplementation normalizes the niacin status in most niacin-deficient serotonin-producing NET patients. A prospective study is warranted.

Transforming growth factor-beta (TGF-beta) signaling is involved in glioma development. The monoclonal antibody fresolimumab (GC1008) can neutralize all mammalian isoforms of TGF-beta, and tumor uptake can be visualized and quantified with Zr-89-fresolimumab PET in mice. The aim of this study was to investigate the fresolimumab uptake in recurrent high-grade gliomas using Zr-89-fresolimumab PET and to assess treatment outcome in patients with recurrent high-grade glioma treated with fresolimumab. Methods: Patients with recurrent glioma were eligible. After intravenous administration of 37 MBq (5 mg) of Zr-89-fresolimumab, PET scans were acquired on day 2 or day 4 after tracer injection. Thereafter, patients were treated with 5 mg of fresolimumab per kilogram intravenously every 3 wk. Zr-89-fresolimumab tumor uptake was quantified as maximum standardized uptake value (SUVmax). MR imaging for response evaluation was performed after 3 infusions or as clinically indicated. Results: Twelve patients with recurrent high-grade glioma were included: 10 glioblastomas, 1 anaplastic oligodendroglioma, and 1 anaplastic astrocytoma. All patients underwent Zr-89-fresolimumab PET 4 d after injection. In 4 patients, an additional PET scan was obtained on day 2 after injection. SUVmax on day 4 in tumor lesions was 4.6 (range, 1.5-13.9) versus a median SUVmean of 0.3 (range, 0.2-0.5) in normal brain tissue. All patients showed clinical or radiologic progression after 1-3 infusions of fresolimumab. Median progression-free survival was 61 d (range, 25-80 d), and median overall survival was 106 d (range, 37-417 d). Conclusion: Zr-89-fresolimumab penetrated recurrent high-grade gliomas very well but did not result in clinical benefit.

In this review the effect of internet-based support programs on psychosocial and physical symptoms resulting from cancer diagnosis and treatment is analyzed. Selection of studies was based on the following criteria: (non-)randomized controlled trials, performed in adult cancer patients, comparing quantitative psychosocial and/or physical outcomes of an internet-based support program with (a) comparison group(s). Literature search yielded 2032 studies of which 16 fulfilled the eligibility criteria. Three different internet-based support programs were identified: social support groups, online therapy for psychosocial/physical symptoms, and online systems integrating information, support, and coaching services. Outcomes improved by these programs in nine studies. Especially fatigue, social support, and distress improved, regardless of the program type. All online systems showed positive effects, mainly for social support and quality of life. This analysis indicates that internet-based support programs are effective in improving psychosocial and physical symptoms in cancer patients. (C) 2015 Elsevier Ireland Ltd. All rights reserved.

The membrane bound glycoprotein mesothelin (MSLN) is a highly specific tumor marker, which is currently exploited as target for drugs. There are only limited data available on MSLN expression by human tumors. Therefore we determined overexpression of MSLN across different tumor types with Functional Genomic mRNA (FGM) profiling of a large cancer database. Results were compared with data in articles reporting immunohistochemical (IHC) MSLN tumor expression. FGM profiling is a technique that allows prediction of biologically relevant overexpression of proteins from a robust data set of mRNA microarrays. This technique was used in a database comprising 19,746 tumors to identify for 41 tumor types the percentage of samples with an overexpression of MSLN compared to a normal background. A literature search was performed to compare the FGM profiling data with studies reporting IHC MSLN tumor expression. FGM profiling showed MSLN overexpression in gastrointestinal (12-36%) and gynecological tumors (20-66%), non-small cell lung cancer (21%) and synovial sarcomas (30%). The overexpression found in thyroid cancers (5%) and renal cell cancers (10%) was not yet reported with IHC analyses. We observed that MSLN amplification rate within esophageal cancer depends on the histotype (31% for adenocarcinomas versus 3% for squamous-cell carcinomas). Subset analysis in breast cancer showed MSLN amplification rates of 28% in triple-negative breast cancer (TNBC) and 33% in basal-like breast cancer. Further subtype analysis of TNBCs showed the highest amplification rate (42%) in the basal-like 1 subtype and the lowest amplification rate (9%) in the luminal androgen receptor subtype.

More than 50 monoclonal antibodies (mAbs), including several antibody-drug conjugates, are in advanced clinical development, forming an important part of the many molecularly targeted anticancer therapeutics currently in development. Drug development is a relatively slow and expensive process, limiting the number of drugs that can be brought into late-stage trials. Development decisions could benefit from quantitative biomarkers, enabling visualization of the tissue distribution of (potentially modified) therapeutic mAbs to confirm effective whole-body target expression, engagement, and modulation and to evaluate heterogeneity across lesions and patients. Such biomarkers may be realized with positron emission tomography imaging of radioactively labeled antibodies, a process called immunoPET. This approach could potentially increase the power and value of early trials by improving patient selection, optimizing dose and schedule, and rationalizing observed drug responses. In this review, we summarize the available literature and the status of clinical trials regarding the potential of immunoPET during early anticancer drug development. (C) 2015 by American Society of Clinical Oncology

Metastatic rectal cancer patients could benefit from novel therapeutic approaches. The signaling network formed by chemokines and their receptors can promote metastasis and resistance to current anticancer treatments. This study assessed the expression of chemokine receptor 4 (CXCR4) and its ligand CXCL12 immuhistochemically in stage IV rectal tumors. Paraffin-embedded primary tumor collected before and after local radiotherapy and systemic treatment with bevacizumab, oxaliplatin and capecitabine was analyzed. Receptor and ligand expression was assessed in the cytoplasm and nucleus of tumor, stromal and normal rectal crypt cells. Baseline expression of CXCR4 and CXCL12 was correlated with patients' pathologic response to treatment. At diagnosis (n=46), 89% of the rectal tumors expressed cytoplasmic CXCR4 and 81% CXCL12. Nuclear CXCR4 expression in tumor cells was present in 30% and nuclear CXCL12 expression in 35% of the tumors. After radiochemotherapy and administration of bevacizumab, nuclear CXCL12 expression was observed in 79% of residual tumors, as compared to 31% of the paired tumor samples expressing nuclear CXCL12 before treatment (P=0.001). There were no differences in CXCR4 or CXCL12 expression at baseline between the patients who had (n=9) and did not have (n=30) a pathologic complete response. Our results show that CXCR4 and CXCL12 are extensively expressed in primary rectal tumors of patients presenting with metastatic disease, while radiochemotherapy and bevacizumab further upregulate CXCL12 expression. These data indicate the importance of the CXCR4/CXCL12 axis in rectal tumor biology, and may suggest the CXCR4/CXCL12 receptor-ligand pair as a potential therapeutic target in metastatic rectal cancer.

It is unknown whether the current dose of fulvestrant, an estrogen receptor (ER) antagonist, is sufficient for maximal ER downregulation in patients with metastatic breast cancer. We performed a feasibility study to assess ER availability before and during fulvestrant. Sixteen patients with ER-positive metastatic breast cancer underwent positron emission tomography/computed tomography (PET/CT) at baseline (scan 1), day 28 (scan 2), and day 84 (scan 3) to monitor tumor [18F]fluoroestradiol (FES) uptake. Incomplete reduction in ER availability was predefined as Significance: Serial imaging of tumor estrogen uptake by FES-PET can give insight into the dose needed for ER antagonists to completely abolish ER. FES-PET showed significant residual ER availability in tumors during fulvestrant therapy in 38% of patients, which was associated with early progression. Cancer Discov; 5(1); 72–81. ©2014 AACR. This article is highlighted in the In This Issue feature, p. 1

Purpose There are indications that a history of allergy may offer some protection against cancer. We studied the relation of three objectively determined allergy markers with cancer mortality and hospitalization risk. Methods Associations between three allergy markers (number of peripheral blood eosinophil counts, skin test positivity, and serum total IgE) with mortality and hospitalization from any type and four common types of cancer (lung, colorectal, prostate, and breast cancer) were assessed in the Vlagtwedde–Vlaardingen cohort (1965–1990), with follow-up of mortality until 31 December 2008. Hospitalization data were available since 1 January 1995. Results There were no significant associations between objective allergy markers and cancer mortality or hospitalization. We found several associations in specific subgroups. A higher number of eosinophils was associated with a decreased risk of colorectal cancer mortality in ever smokers HR (95 % CI) = 0.61 (0.45–0.83) and in males 0.59 (0.42–0.83); however, no overall association was observed 0.84 (0.64–1.09). Skin test positivity was associated with a decreased risk of any cancer mortality only among females 0.59 (0.38–0.91) and showed no overall association 0.83 (0.67–1.04). Serum total IgE levels were associated with an increased risk of lung cancer mortality among females 4.64 (1.04–20.70), but with a decreased risk of cancer hospitalization in ever smokers 0.77 (0.61–0.97) and males 0.72 (0.55–0.93); however, no overall associations were observed [mortality 0.99 (0.79–1.25), and hospitalization 0.86 (0.71–1.04)]. Conclusions We found no associations between objective allergy markers and cancer in the total population. However, skin test positivity and a high number of eosinophils were associated with a reduced risk to die of cancer in specific subgroups. Hence, it seems important to study specific subgroups defined by gender and smoking habits in order to identify allergy markers of predictive value for cancer mortality. Electronic supplementary material The online version of this article (doi:10.1007/s10552-014-0489-9) contains supplementary material, which is available to authorized users.

The estrogen receptor (ER) is a target for endocrine therapy in breast cancer patients. Individual quantification of ER alpha and ER beta expression, rather than total ER levels, might enable better prediction of the response to treatment. We recently developed the tracer 2-F-18-fluoro-6-(6-hydroxynaphthalen-2-yl) pyridin-3-ol (F-18-FHNP) for assessment of ER beta levels with PET. In the current study, we investigated several pharmacokinetic analysis methods to quantify changes in ER beta availability with F-18-FHNP PET. Methods: Male nude rats were subcutaneously inoculated in the shoulder with ER alpha/ER beta-expressing SKOV3 human ovarian cancer cells. Two weeks after tumor inoculation, a dynamic F-18-FHNP PET scan with arterial blood sampling was acquired from rats treated with vehicle or various concentrations of estradiol (nonspecific ER agonist) or genistein (ER beta-selective agonist). Different pharmacokinetic models were applied to quantify ER beta availability in the tumor. Results: Irreversible-uptake compartmental models fitted the kinetics of F-18-FHNP uptake better than reversible models. The irreversible 3-tissue-compartment model, which included both the parent and the metabolite input function, gave results comparable to those of the irreversible 2-tissue-compartment model with only a parent input function, indicating that radioactive metabolites contributed little to the tumor uptake. Patlak graphical analysis gave metabolic rates (K-i, the irreversible uptake rate constant) comparable to compartment modeling. The K-i values correlated well with ER beta expression but not with ER alpha, confirming that K-i is a suitable parameter to quantify ER beta expression. SUVs at 60 min after tracer injection also correlated (r(2) - 0.47; P - 0.04) with ER beta expression. A reduction in F-18-FHNP tumor uptake and Ki values was observed in the presence of estradiol or genistein. Conclusion: F-18-FHNP PET enables assessment of ER beta availability in tumor-bearing rats. The most suitable parameter to quantify ER beta expression is the K-i. However, a simplified static imaging protocol for determining the SUVs can be applied to assess ER beta levels.

Context. Many breast cancer patients have unmet informational and psychosocial needs after treatment completion. A psychoeducational intervention may be well suited to support these patients.Objectives. The purpose of this multicenter randomized controlled trial was to examine the effectiveness of a web-based tailored psychoeducational program (ENCOURAGE) for breast cancer patients, which aims to empower patients to take control over prevailing problems.Methods. Female breast cancer patients from two hospitals in The Netherlands who recently completed (neo-)adjuvant chemotherapy were randomly assigned to standard care or 12-week access to the ENCOURAGE program providing fully automated information problem-solving strategies, resources, and services for reported problems. At six and 12 weeks, patients completed self-report questions on optimism and control over the future (primary outcome), feelings of being informed, and acceptance of the illness. At baseline and 12 weeks, distress and quality of life questionnaires were completed.Results. About 138 patients were included. Almost all patients (67 of 69) visited ENCOURAGE as requested. No differences between the control and intervention group were observed for primary and secondary outcomes. An unplanned subgroup analysis showed that in clinically distressed patients (N = 57 at baseline; 41%), use of the ENCOURAGE program increased optimism and control over the future at 12 weeks more than in patients in the control group (Cohen's d = 0.65).Conclusion. Although the effectiveness was not demonstrated, a subgroup of women treated for breast cancer can probably be supported by the program. The results of the present study are a starting point for further development and use of the program.

Background The European Society for Medical Oncology (ESMO) has developed the ESMO Magnitude of Clinical Benefit Scale (ESMO-MCBS), a tool to assess the magnitude of clinical benefit from new cancer therapies. Grading is guided by a dual rule comparing the relative benefit (RB) and the absolute benefit (AB) achieved by the therapy to prespecified threshold values. The ESMO-MCBS v1.0 dual rule evaluates the RB of an experimental treatment based on the lower limit of the 95%CI (LL95%CI) for the hazard ratio (HR) along with an AB threshold. This dual rule addresses two goals: inclusiveness: not unfairly penalising experimental treatments from trials designed with adequate power targeting clinically meaningful relative benefit; and discernment: penalising trials designed to detect a small inconsequential benefit. Methods Based on 50 000 simulations of plausible trial scenarios, the sensitivity and specificity of the LL95%CI rule and the ESMO-MCBS dual rule, the robustness of their characteristics for reasonable power and range of targeted and true HRs, are examined. The per cent acceptance of maximal preliminary grade is compared with other dual rules based on point estimate (PE) thresholds for RB. Results For particularly small or particularly large studies, the observed benefit needs to be relatively big for the ESMO-MCBS dual rule to be satisfied and the maximal grade awarded. Compared with approaches that evaluate RB using the PE thresholds, simulations demonstrate that the MCBS approach better exhibits the desired behaviour achieving the goals of both inclusiveness and discernment. Conclusions RB assessment using the LL95%CI for HR rather than a PE threshold has two advantages: it diminishes the probability of excluding big benefit positive studies from achieving due credit and, when combined with the AB assessment, it increases the probability of downgrading a trial with a statistically significant but clinically insignificant observed benefit., SCOPUS: ar.j, info:eu-repo/semantics/published

Purpose c-MET and its ligand hepatocyte growth factor are often dysregulated in human cancers. Dynamic changes in c-MET expression occur and might predict drug efficacy or emergence of resistance. Noninvasive visualization of c-MET dynamics could therefore potentially guide c-MET-directed therapies. We investigated the feasibility of 89Zr-labelled one-armed c-MET antibody onartuzumab PET for detecting relevant changes in c-MET levels induced by c-MET-mediated epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor erlotinib resistance or heat shock protein-90 (HSP90) inhibitor NVP-AUY-922 treatment in human non-small-cell lung cancer (NSCLC) xenografts. Methods In vitro membrane c-MET levels were determined by flow cytometry. HCC827ErlRes, an erlotinib-resistant clone with c-MET upregulation, was generated from the exon-19 EGFR-mutant human NSCLC cell line HCC827. Mice bearing HCC827 and HCC827ErlRes tumours in opposite flanks underwent 89Zr-onartuzumab PET scans. The HCC827-xenografted mice underwent 89Zr-onartuzumab PET scans before treatment and while receiving biweekly intraperitoneal injections of 100 mg/kg NVP-AUY-922 or vehicle. Ex vivo, tumour c-MET immunohistochemistry was correlated with the imaging results. Results In vitro, membrane c-MET was upregulated in HCC827ErlRes tumours by 213 ± 44% in relation to the level in HCC827 tumours, while c-MET was downregulated by 69 ± 9% in HCC827 tumours following treatment with NVP-AUY-922. In vivo, 89Zr-onartuzumab uptake was 26% higher (P

The human epidermal growth factor receptor 3 (HER3) is an interesting target for antitumor therapy. For optimal HER3 signaling inhibition, a biparatopic Nanobody construct (MSB0010853) was developed that binds 2 different HER3 epitopes. In addition, MSB0010853 contains a third HER3 epitope that binds albumin to extend its circulation time. MSB0010853 is cross-reactive with HER3 and albumin of mouse origin. We aimed to gain insight into MSB0010853 biodistribution and tumor uptake by radiolabeling the Nanobody construct with Zr-89. Methods: MSB0010853 was radiolabeled with Zr-89. Dose-and time-dependent tumor uptake was studied in nude BALB/c mice bearing a subcutaneous HER3 overexpressing H441 non-small cell lung cancer xenograft. Dose-dependent biodistribution of Zr-89-MSB0010853 was assessed ex vivo at 24 h after intravenous injection. Protein doses of 5, 10, 25, 100, and 1,000 mgwere used. Time-dependent biodistribution of MSB0010853 was analyzed ex vivo at 3, 6, 24, and 96 h after intravenous administration of 25 mg of Zr-89-MSB0010853. PET imaging and biodistribution were performed 24 h after administration of 25 mu g of Zr-89-MSB0010853 to mice bearing human H441, FaDu (high HER3 expression), or Calu-1 (no HER3 expression) tumor xenografts. Results: Radiolabeling of MSB0010853 with Zr-89 was performed with a radiochemical purity of greater than 95%. Ex vivo biodistribution showed protein dose-and time-dependent distribution of Zr-89-MSB0010853 in all organs. Uptake of Zr-89-MSB0010853 in H441 tumors was only time-dependent. Tumor could be visualized up to at least 96 h after injection. The highest mean SUV of 0.6 +/- 0.2 was observed at 24 h after injection of 25 mu g of Zr-89-MSB0010853. Zr-89-MSB0010853 tumor uptake correlated with HER3 expression and was highest in H441 (6.2 +/- 1.1 percentage injected dose per gram [% ID/g]) and lowest in Calu-1 (2.3 +/- 0.3 % ID/g) xenografts. Conclusion: Zr-89-MSB0010853 organ distribution and tumor uptake in mice are time-dependent, and tumor uptake correlates with HER3 expression. In contrast to tumor uptake except for kidney uptake, organ distribution of Zr-89-MSB0010853 is protein dose-dependent for the tested doses. Zr-89-MSB0010853 PET imaging gives insight into the in vivo behavior of MSB0010853.

In-vivo fluorescently labelled drug (bevacizumab) breast cancer specimen where obtained from patients. We propose a new structured method to determine the optimal classification threshold in targeted fluorescence intra-operative imaging.

11519 Background: Despite RAS selection, one third of patients with metastatic RAS wild-type colorectal cancer (mCRC) do not benefit from anti-EGFR inhibitors. Therefore, an additional or more accurate predictive biomarker is needed to identify patients with primary resistant mCRC. Methods: In the IMPACT-CRC trial (NCT02117466) patients with chemotherapy refractory mCRC received 500 mg/m2 cetuximab every 2 weeks. Before the first dose and just before the second dose, patients underwent a 18F-FDG PET/CT (FDG PET). PET scans were quantitatively assessed by manual tumor delineation of ≤ 5 lesions, 2 per organ. Outcome is reported in total lesion glycolysis (TLG), defined as metabolic tumor volume times mean standard uptake value of the tumor. An optimal threshold to assess metabolic response was defined as decrease in TLG ≥15%. Quantitative data were correlated with CT evaluation after 8 weeks of treatment according to RECIST v1.1. Results: Out of 35 patients, 1 was excluded due to an infusion reaction. Median age was 64 years, 74% was male, 4 patients had a BRAF mutated tumor and 9 patients had right-sided primary tumors. 62% of patients had stable disease or partial response on CT after 8 weeks. At the time of this analysis, 88% of patients had progressive disease and 71% had died. Of the patients with right-sided tumors 11% had treatment benefit, compared to 80% in the left-sided group (p = 0.001). None of the 9 metabolic non-responders had treatment benefit, whereas 83% of the metabolic responders had treatment benefit according to RECIST v1.1. After adjustment for age, WHO score, BRAF mutation, sex and primary tumor site, FDG PET response remained correlated with PFS and OS (p = 0.002 and p = 0.014). Conclusions: Early evaluation of metabolic response after 1 dose of cetuximab is highly and independently predictive for treatment benefit with a 100% negative predictive value. Implementation of early FDG-PET evaluation in daily clinical practice can prevent unnecessary toxicity, costs of ineffective treatment and allows timely treatment adjustment for patients with mCRC undergoing anti-EGFR treatment. Clinical trial information: NCT02117466.

A workshop at the National Cancer Institute on May 2, 2016, considered the current state of imaging in assessment of immunotherapy. Immunotherapy has shown some remarkable and prolonged responses in the treatment of tumors. However, responses are variable and frequently delayed, complicating the evaluation of new immunotherapy agents and customizing treatment for individual patients. Early anatomic imaging may show that a tumor has increased in size, but this could represent pseudoprogression. On the basis of imaging, clinicians must decide if they should stop, pause, or continue treatment. Other imaging technologies and approaches are being developed to improve the measurement of response in patients receiving immunotherapy. Imaging methods that are being evaluated include radiomic methods using CT, MRI, and F-18-FDG PET, as well as new radiolabeled small molecules, antibodies, and antibody fragments to image the tumor microenvironment, immune status, and changes over the course of therapy. Current studies of immunotherapy can take advantage of these available imaging options to explore and validate their use. Collection of CT, PET, and MR images along with outcomes from trials is critical to develop improved methods of assessment.

Tumours respond differently to immunotherapies compared with chemotherapeutic drugs, raising questions about the assessment of changes in tumour burden—a mainstay of evaluation of cancer therapeutics that provides key information about objective response and disease progression. A consensus guideline—iRECIST—was developed by the RECIST working group for the use of modified Response Evaluation Criteria in Solid Tumours (RECIST version 1.1) in cancer immunotherapy trials, to ensure consistent design and data collection, facilitate the ongoing collection of trial data, and ultimate validation of the guideline. This guideline describes a standard approach to solid tumour measurements and definitions for objective change in tumour size for use in trials in which an immunotherapy is used. Additionally, it defines the minimum datapoints required from future trials and those currently in development to facilitate the compilation of a data warehouse to use to later validate iRECIST. An unprecedented number of trials have been done, initiated, or are planned to test new immune modulators for cancer therapy using a variety of modified response criteria. This guideline will allow consistent conduct, interpretation, and analysis of trials of immunotherapies.

In theranostics, radiolabeled compounds are used to determine a treatment strategy by combining therapeutics and diagnostics in the same agent. Monoclonal antibodies (mAbs) and antibody-related therapeutics represent a rapidly expanding group of cancer medicines. Theranostic approaches using these drugs in oncology are particularly interesting because antibodies are designed against specific targets on the tumor cell membrane and immune cells as well as targets in the tumor microenvironment. In addition, these drugs are relatively easy to radiolabel. Noninvasive molecular imaging techniques, such as SPECT and PET, provide information on the whole-body distribution of radiolabeled mAbs and antibody-related therapeutics. Molecular antibody imaging can potentially elucidate drug target expression, tracer uptake in the tumor, tumor saturation, and heterogeneity for these parameters within the tumor. These data can support drug development and may aid in patient stratification and monitoring of the treatment response. Selecting a radionuclide for theranostic purposes generally starts by matching the serum half-life of the mAb or antibody-related therapeutic and the physical half-life of the radionuclide. Furthermore, PET imaging allows better quantification than the SPECT technique. This information has increased interest in theranostics using PET radionuclides with a relatively long physical half-life, such as Zr-89. In this review, we provide an overview of ongoing research on mAbs and antibody-related theranostics in preclinical and clinical oncologic settings. We identified 24 antibodies or antibody-related therapeutics labeled with PET radionuclides for theranostic purposes in patients. For this approach to become integrated in standard care, further standardization with respect to the procedures involved is required.

Sentinel lymph node biopsy (SLNB) is the standard of care for axillary staging in clinically node-negative (cN0) breast cancer patients without neoadjuvant chemotherapy (NAC). The application of SLNB in patients receiving NAC has also been explored. Evidence supports its use after NAC in pretreatment cN0 patients. Nonetheless, its routine use in all the pretreatment node-positive patients who become cN0 after NAC is unjustified due to the unacceptably high false-negative rate, which can be improved in a subset of patients. Axillary surgery omission in selected patients with a low risk of ALN metastasis has gained more and more research interest because the SLNs are tumor-free in more than 70% of all patients. To avoid drawbacks of conventional mapping methods, novel techniques for SLN detection have been developed and shown to be highly accurate in patients with early breast cancer. This article reviews the progress in SLNB in patients with breast cancer.

Treatment of human epidermal growth factor receptor 2 (HER2)-driven breast cancer with tyrosine kinase inhibitor lapatinib can induce a compensatory HER3 increase, which may attenuate antitumor efficacy. Therefore, we explored in vivo HER3 tumor status assessment after lapatinib treatment with zirconium-89 ((89)Zr)-labeled anti-HER3 antibody mAb3481 positron emission tomography (PET). Lapatinib effects on HER3 cell surface expression and mAb3481 internalization were evaluated in human breast (BT474, SKBR3) and gastric (N87) cancer cell lines using flow cytometry. Next, in vivo effects of daily lapatinib treatment on(89)Zr-mAb3481 BT474 and N87 xenograft tumor uptake were studied. PET-scans (BT474 only) were made after daily lapatinib treatment for 9 days, starting 3 days prior to (89)Zr-mAb3481 administration. Subsequently, ex vivo (89)Zr-mAb3481 organ distribution analysis was performed and HER3 tumor levels were measured with Western blot and immunohistochemistry. In vitro, lapatinib increased membranous HER3 in BT474, SKBR3 and N87 cells, and consequently mAb3481 internalization 1.7-fold (BT474), 1.4-fold (SKBR3) and 1.4-fold (N87). (89)Zr-mAb3481 BT474 tumor uptake was remarkably high at SUVmean 5.6±0.6 (51.8±7.7%ID/g) using a 10 μg (89)Zr-mAb3481 protein dose in vehicle-treated mice. However, compared to vehicle, lapatinib did not affect (89)Zr-mAb3481 ex vivo uptake in BT474 and N87 tumors, while HER3 tumor expression remained unchanged. In conclusion, lapatinib increased in vitro HER3 tumor cell expression, but not when these cells were xenografted. (89)Zr-mAb3481 PET accurately reflected HER3 tumor status. (89)Zr-mAb3481 PET showed high, HER3-specific tumor uptake, and such an approach might sensitively assess HER3 tumor heterogeneity and treatment response in patients.

Human cells have evolved elaborate mechanisms for responding to DNA damage to maintain genome stability and prevent carcinogenesis. For instance, the cell cycle can be arrested at different stages to allow time for DNA repair. The APC/C(C) (dh1) ubiquitin ligase mainly regulates mitotic exit but is also implicated in the DNA damage-induced G2 arrest. However, it is currently unknown whether APC/C(C) (dh1) also contributes to DNA repair. Here, we show that Cdh1 depletion causes increased levels of genomic instability and enhanced sensitivity to DNA-damaging agents. Using an integrated proteomics and bioinformatics approach, we identify CtIP, a DNA-end resection factor, as a novel APC/C(C) (dh1) target. CtIP interacts with Cdh1 through a conserved KEN box, mutation of which impedes ubiquitylation and downregulation of CtIP both during G1 and after DNA damage in G2. Finally, we find that abrogating the CtIP-Cdh1 interaction results in delayed CtIP clearance from DNA damage foci, increased DNA-end resection, and reduced homologous recombination efficiency. Combined, our results highlight the impact of APC/C(C) (dh1) on the maintenance of genome integrity and show that this is, at least partially, achieved by controlling CtIP stability in a cell cycle- and DNA damage-dependent manner.

Purpose: HSP90 chaperones have key client proteins that are involved in all hallmarks of breast cancer growth and progression. The primary aim of this clinical trial was to evaluate the feasibility of using 89Zr-trastuzumab PET (for HER2-positive breast cancer) or 89Zr-bevacizumab PET [for estrogen receptor (ER)–positive breast cancer] to determine in vivo degradation of client proteins caused by the novel HSP90 inhibitor NVP-AUY922. Experimental Design: Of note, 70 mg/m2 NVP-AUY922 was administered intravenously in a weekly schedule to patients with advanced HER2 or ER-positive breast cancer. Biomarker analysis consisted of serial PET imaging with 2[18F]fluoro-2-deoxy-D-glucose (FDG), 89Zr-trastuzumab, or 89Zr-bevacizumab. Response evaluation was performed according to RECIST1.0. FDG, 89Zr-trastuzumab, and 89Zr-bevacizumab distributions were scored visually and quantitatively by calculating the maximum standardized uptake values (SUVmax). In blood samples, serial HSP70 levels, extracellular form of HER2 (HER2-ECD), and pharmacokinetic and pharmacodynamic parameters were measured. Results: Sixteen patients (ten HER2-positive and six ER-positive tumors) were included. One partial response was observed; seven patients showed stable disease. SUVmax change in individual tumor lesions on baseline versus 3 weeks 89Zr-trastuzumab PET was heterogeneous and related to size change on CT after 8 weeks treatment (r2 = 0.69; P = 0.006). Tumor response on 89Zr-bevacizumab PET and FDG-PET was not correlated with CT response. Conclusions: NVP-AUY922 showed proof-of-concept clinical response in HER2-amplified metastatic breast cancer. Early change on 89Zr-trastuzumab PET was positively associated with change in size of individual lesions assessed by CT. Clin Cancer Res; 20(15); 3945–54. ©2014 AACR.

Everolimus increases progression-free survival in patients with advanced neuroendocrine tumors (NETs). Currently, no biomarkers are available for early selection of patients who will benefit from everolimus. Everolimus can reduce vascular endothelial growth factor A (VEGF-A) production by tumor cells. Therefore, we aimed to investigate the effect of everolimus on tumor uptake of the radioactive-labeled VEGF-A antibody bevacizumab with PET in NET patients. Methods: Patients with advanced progressive well-differentiated NETs underwent Zr-89-bevacizumab PET scans before and at 2 and 12 wk during everolimus treatment. Zr-89-bevacizumab uptake was quantified by the maximum standardized uptake value (SUVmax). Tumor response and the percentage change in the sum of target lesion diameters were determined according to Response Evaluation Criteria in Solid Tumors 1.1 on CT (3 monthly). Results: In 4 of the 14 patients entered, no tumor lesions were visualized with Zr-89-bevacizumab PET. In the remaining patients, 19% of tumor lesions 1 cm or greater known by CT were visualized. Tumor SUVmax decreased during everolimus treatment, with a median of -7% at 2 wk (P = 0.09) and a median of -35% at 12 wk (P

Purpose Progressive disease (PD) per Response Evaluation Criteria in Solid Tumours (RECIST) 1.1 is defined as growth of measurable target lesions, presence of new lesions or unequivocal progression of non-target disease. In this manuscript we explored whether a more refined categorisation of tumour response and/or these components of progression, varying over time, can improve prediction of overall survival (OS) in the RECIST database. Methods Data were randomly selected from 13 randomised clinical trials (3758 patients with breast, lung or colorectal cancer). A maximum of five target lesions contributed to the sum of longest diameters. At each measurement time we determined: best target response as best % improvement from baseline; tumour growth of target lesions as worst % change and worst rate of increase (mm/week) from nadir; presence of new lesions and occurrence of non-target PD. OS was analysed by tumour type using Cox regression, adjusting for baseline sum and including these parameters as time-dependent covariates. Results 36% of patients had new lesions, 28% non-target PD and 49% experienced target lesion growth (median strongest growth 1.5 mm/week). Regardless of tumour type, presence of new lesions (hazard ratio (HR) ranging 1.5–2.3) and non-target PD (HR 1.5–2.0) were strongly associated with worse OS. The explanatory value of tumour growth for OS was low compared to the other components. Conclusion Modelling target lesion tumour growth did not show a marked improvement in OS prediction over and above the other components. These analyses enable a better understanding of the role of each component in PD evaluation. Work is ongoing to incorporate this information into an updated version of RECIST with enhanced prediction of subsequent survival.

The human epidermal growth factor receptor (HER) family members are targeted by a growing numbers of small molecules and monoclonal antibodies. Resistance against the epidermal growth factor receptor (EGFR) and HER2-targeting agents is a clinically relevant problem forcing research on optimizing targeting of the HER family. In view of its overexpression in tumors, and compensatory role in HER signaling, HER3 has gained much interest as a potential additional target within the HER family. It is the only member of the HER family lacking intrinsic tyrosine kinase activity and therefore its role in cancer has long been underestimated. Drugs that block HER3 or interfere with HER3 dimer signaling, including fully human anti-HER3 antibodies, bispecific antibodies and tyrosine kinase inhibitors (TKIs), are currently becoming available. Several compounds have already entered clinical trial. In the meantime potential biomarkers are tested such as tumor analysis of HER3 expression, functional assays for downstream effector molecules and molecular imaging techniques. This review describes the biology and relevance of HER3 in cancer, agents targeting HER3 and potential biomarkers for effect of HER3-targeting.

Anticalins are a novel class of biopharmaceuticals, displaying highly desirable attributes as imaging agents. The anticalin PRS-110 was rationally engineered to target the oncogene MET with high affinity and specificity. The aim of this study was to visualize MET expression and analyze biodistribution of Zr-89-labeled PRS-110 in human tumor-bearing mice. Methods: Zr-89-PRS-110 was generated. For biodistribution studies (96 h after injection of tracer) 10 mu g of Zr-89-PRS-110 (with 0-490 mu g of unlabeled PRS-110) were injected into BALB/c mice bearing high MET-expressing H441 non-small cell lung cancer xenografts. Further characterization with PET imaging was performed at 6, 24, 48, and 96 h after injection of 50 mu g of Zr-89-PRS-110 into mice bearing H441, primary glioblastoma U87-MG (intermediate MET), or ovarian cancer A2780 (low MET) xenografts. Drug distribution was also analyzed ex vivo using fluorescently labeled PRS-110. Results: Biodistribution analyses showed a dose-dependent tumor uptake of Zr-89-PRS-110, with the highest fractional tumor uptake at 10 mu g of Zr-89-PRS-110, with no unlabeled PRS-110. Small-animal PET imaging supported by biodistribution data revealed specific tumor uptake of Zr-89-PRS-110 in the METexpressing H441 and U87-MG tumors whereas the MET-negative A2780 tumor model showed a lower uptake similar to a non-MET binder anticalin control. Tumor uptake increased up to 24 h after tracer injection and remained high, whereas uptake in other organs decreased over time. Ex vivo fluorescence revealed intracellular presence of PRS-110. Conclusion: Zr-89-PRS-110 specifically accumulates in MET-expressing tumors in a receptor density-dependent manner. PET imaging provides real-time noninvasive information about PRS-110 distribution and tumor accumulation in preclinical models.

The costs of cancer care grow exponentially. It has been argued that there is a linear relation between costs and outcome: the more a country spends on cancer care, the better the outcome. We try to dispel this myth, by showing that the relation is not linear at all and by describing other factors in the cancer care delivery process that have an impact on outcome. We show that there is a correlation between health care expenditure and life expectancy at birth, but that there is no correlation between number of deaths per 100,000 and cost per person spent on cancer in general, neither in lung, breast, colorectal and prostate cancer. Furthermore, a decrease in survival can be related to accessibility, affordability or equity issues, but also to factors such as life style. In the real world the process of cancer delivery is complex and dynamic, with many (potential) innovations. When efficacy is proven and an innovation is considered clinically relevant, the innovation has to be incorporated in evidence based clinical guidelines. However, implementation in such a guideline is still no guarantee for optimal adoption and diffusion of an innovation. Cancer care delivery also goes beyond matters related to health-systems and cancer costs, new technologies, reimbursement agencies, hospitals, and health-care professionals by increasingly involving shared decision making. An optimal process of cancer care delivery consists of the use of new and existing diagnostic tests and treatment strategies of high quality and is effective, safe, patient centred, efficient and timely. Such health system is highly recommended and all stakeholders in society will benefit.

The humanized monoclonal antibody with high affinity for the human epidermal growth factor receptor (HER) 3, RG7116, is a glycoengineered, IgG1 class antibody. By labeling RG7116 with zirconium-89 (Zr-89) we aimed to visualize in vivo HER 3 expression and study the biodistribution of this antibody in human tumor-bearing mice. Biodistribution of 89Zr-RG7116 was studied in subcutaneously xenografted FaDu tumor cells (HER 3-positive). Dose-dependency of Zr-89-RG7116 organ distribution and specific tumor uptake was assessed by administering doses ranging from 0.05 to 10 mg/kg RG7116 to SCID/Beige mice. Biodistribution was analyzed at 24 and 144 h after injection. MicroPET imaging was performed at 1, 3, and 6 days after injection of 1.0 mg/kg Zr-89-RG7116 in the FaDu, H441, QG-56 and Calu-1 xenografts with varying HER 3 expression. The excised tumors were analyzed for HER 3 expression. Biodistribution analyses showed a dose-and time-dependent Zr-89-RG7116 tumor uptake in FaDu tumors. The highest tumor uptake of Zr-89-RG7116 was observed in the 0.05 mg/kg dose group with 27.5% ID/g at 144 h after tracer injection. MicroPET imaging revealed specific tumor uptake of Zr-89-RG7116 in FaDu and H441 models with an increase in tumor uptake over time. Biodistribution data was consistent with the microPET findings in FaDu, H441, QG56 and Calu-1 xenografts, which correlated with HER 3 expression levels. In conclusion, Zr-89-RG7116 specifically accumulates in HER 3 expressing tumors. PET imaging with this tracer provides realtime non-invasive information about RG7116 distribution, tumor targeting and tumor HER 3 expression levels.

Purpose: With the increasing use of novel targeted agents and the development of high imaging techniques, response evaluation criteria in solid tumour (RECIST) 1.1 developed primarily for cytotoxic agents and anatomic imaging, has demonstrated limitations. A survey was conducted of RECIST users to identify concerns and their suggestions for future RECIST criteria.Methods: 140 key partners of the RECIST collaboration were asked to complete a questionnaire. The 49 questions concerned (a) satisfaction and concerns with RECIST 1.1; (b) use of modified RECIST criteria and (c) suggestions for the next RECIST Version.Results: Sixty-five replies were received. 52.3% responders were satisfied with RECIST 1.1, while 10.8% indicated dissatisfaction. Areas of potential weakness included: (a) lack of incorporation of potential early indicators of response such as functional imaging, (b) lack of validation in rarer tumour types and (c) lack of validation for novel (targeted) agents. Suggestions were multiple, with highest numbers on two points: developing sub-criteria for certain disease types and including advanced imaging techniques for the evaluation.Conclusions: Constructive suggestions were received for optimising the next version. Ongoing data collection will make it possible to investigate the possible utilisation of fluorodeoxyglucose-positron emission tomography (FDG-PET) imaging in tumour assessment, to verify whether RECIST is/can still be applicable in novel targeted therapy and to consider the need for criteria for specific disease types. (C) 2013 Elsevier Ltd. All rights reserved.

The biogenic amines dopamine and serotonin are neurotransmitters and hormones, which are mainly produced in the central nervous system and in the gastro-intestinal tract. They execute local and systemic functions such as intestinal motility and tissue repair. Dopamine and serotonin are primarily stored in and transported by platelets. This review focuses on the recently recognized role of dopamine and serotonin in the regulation of tumor behavior by affecting angiogenesis and tumor cell proliferation. Preclinical studies demonstrate that dopamine inhibits tumor growth via activation of dopamine receptor D2 on endothelial and tumor cells. Serotonin stimulates tumor growth via activation of serotonin receptor 2B on endothelial cells and serotonin receptors on tumor cells. Drugs that stimulate dopamine receptor D2 or inhibit serotonin receptors are available and therefore clinical intervention studies for cancer patients are within reach. (C) 2014 Elsevier Ltd. All rights reserved.

Type 2 diabetes mellitus (T2DM) is associated with a higher risk of cancer and cancer-related mortality. Increased blood glucose and insulin levels in T2DM patients may be, at least in part, responsible for this effect. Indeed, lowering glucose and/or insulin levels pharmacologically appears to reduce cancer risk and progression, as has been demonstrated for the biguanide metformin in observational studies. Studies investigating the influence of sulfonylurea derivatives (SUs) on cancer risk have provided conflicting results, partly due to comparisons with metformin. Furthermore, little attention has been paid to within-class differences in systemic and off-target effects of the SUs. The aim of this systematic review is to discuss the available preclinical and clinical evidence on how the different SUs influence cancer development and risk. Databases including PubMed, Cochrane, Database of Abstracts on Reviews and Effectiveness, and trial registries were systematically searched for available clinical and preclinical evidence on within-class differences of SUs and cancer risk. The overall preclinical and clinical evidence suggest that the influence of SUs on cancer risk in T2DM patients differs between the various SUs. Potential mechanisms include differing affinities for the sulfonylurea receptors and thus differential systemic insulin exposure and off-target anti-cancer effects mediated for example through potassium transporters and drug export pumps. Preclinical evidence supports potential anti-cancer effects of SUs, which are of interest for further studies and potentially repurposing of SUs. At this time, the evidence on differences in cancer risk between SUs is not strong enough to guide clinical decision making.