Analysis of the contribution of macrophages to the overall tumor PD-L1 microenvironment using a screening multi-tumor tissue microarray and rapid multiplex fluorescence digital phenotyping approach

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Background: Programmed death ligand-1 (PD-L1) contributes to immune suppression in the tumor microenvironment (TME) by interacting with programmed cell death-1 (PD-1) on infiltrating T lymphocytes leading to tumor immune escape. Application of omics technologies has shed light on the relevance of the TME for response to immunotherapies and development of novel treatment options. Here we have applied a multi-plex immunofluorescence/multi-tumor tissue microarray (TMA) approach to examine the immunobiology of different TMEs with respect to the contribution by tumor cells and macrophages to overall PD-L1 expression. Methods: A TMA comprising 11 tumor types and a total of 144 different donors, each represented by two cores [1mm; 1 from invasive margin (IM) and 1 from tumor center (TC)], was stained using Ultivue’s Immuno8 FixVUE panel (CD3, CD4, CD8, FOXP3, CD68, PD-1, PD-L1, pan-CK/SOX10). Whole slide images from two rounds of imaging (x20 magnification; four markers in each round) were aligned using Ultivue's UltiStacker software based on the nuclear counterstains from the two imaging rounds, to provide precise marker colocalization data. Cell phenotype data for each core was generated using Visiopharm software. Results: Overall PD-L1 positivity was greatest for NSCLC, SCLC, TNBC and gastric cancer ranging from approximately 600-1000 PD-L1+ cells/mm2/core, compared with CRC, breast, pancreatic, liver, and gastric esophageal junction (GOJ) cancers (approx. 50-300 PD-L1+ cells/mm2/core). Contribution by macrophages to overall PD-L1 expression (dual CD68+/PD-L1+) varied by tumor type representing 25-35% for NSCLC (SCC and ADC) and gastric cancer, whereas a converse pattern was apparent for SCLC, TNBC, breast (ER+ and Her2+) and pancreatic cancers where PD-L1+ macrophages accounted for a large proportion (approx. 60-85%) of overall tumor PD-L1 expression. Interestingly, as a proportion of total macrophage infiltration, approximately 65% of CD68+ macrophages were PD-L1+ for SCLC and TNBC, compared with less than 10% for pancreatic and liver cancer. Spatial analysis revealed PD-L1+ macrophage infiltration to be generally higher for IM versus TC, and the distribution between tumor (CK+) and stroma (CK-) remained similar despite exclusion of CD3+/CD8+ cytotoxic T cells from CK+ tumor regions for pancreatic and liver cancer. Conclusions: Taken together, these data illustrate the benefits of combining multiplexed immunofluorescence staining, with digital analysis of cell phenotypes within well characterized tumor samples to better understand the relative immunobiology of different TMEs. Here we demonstrate that the relative contribution of macrophages to the overall PD-L1 microenvironment varies between tumor types, which may help guide options for successful immunotherapy strategies.

Abstract 2778: Comparative multiplex digital phenotyping of the tumor microenvironment across multiple tumor types using a well characterized multi-tumor tissue microarray

The tumor microenvironment (TME) represents a complex interaction of immune and host cells and can be described broadly as ‘inflamed', ‘immune excluded' and ‘desert'; categories that may serve as predictive parameters for response to different immunotherapies. Multiplexed fluorescence and associated digital imaging platforms are important tools for defining the spatial components of the TME and can accelerate development of novel immunotherapy strategies. To investigate the TME across multiple tumor types simultaneously we have utilized a multi-tumor tissue microarray (TMA) covering 11 different tumor types comprising a total of 144 cases, each in duplicate with cores (1mm) taken from invasive margin (IM) and tumor center (TC). The TMA was stained using the UltiMapper I/O Immuno8 panel, which includes markers for CD3, CD4, CD8, FOXP3, CD68, PD-1, PD-L1, and a pan-CK/SOX10 cocktail as a tumor indicator. Stained TMAs were scanned on a fluorescence whole slide scanner (20X magnification) and marker images aligned using the UltiStacker software using the nuclear counterstain images as references from two rounds of imaging, to provide accurate marker colocalization data. Digital image analysis was performed using Visiopharm software to generate cell phenotype data, including localization to tumor and stroma, for each of the 288 cores. Comparative analysis of all tumor types regardless of core location (IM and TC combined) revealed gastric cancer, CRC, TNBC and NSCLC to be most highly infiltrated with CD3+ T cells, and ER+ and Her2+ breast cancers least infiltrated. The contribution of cytotoxic T cells (CD3+ CD8+) to the TME was greater for gastric cancer (approx. 50%) compared with NSCLC (approx. 20%) and the proportion of cytotoxic T cells activated/exhausted as defined by expression of PD-1 ranged from approx. 25% (eg. TNBC, CRC) to 1% (eg. ER+ BC). Spatial localization analyses of cytotoxic T cells revealed pancreatic and hepatic cancers as the most ‘excluded' as evidenced by low CD3+/CD8+ T cell numbers in tumor (CK+) compared with stromal regions (CK-). Interestingly, cytotoxic T cells with an exhausted phenotype (CD3+ CD8+ PD-1+) were preferentially infiltrated within CK+ tumor areas compared with stroma (CK-) for inflamed tumors such as gastric, TNBC and CRC. These data highlight the benefits of combining a fast, multiplexed staining protocol, with a detailed digital analysis of immune phenotypes spatially within well characterized tumor samples to better understand the TME (eg. inflamed, excluded) and identify tumor types more likely to benefit from different immunotherapeutic strategies.

Citation Format: Marie Cumberbatch, Douglas Wood, Christopher Womack, Milan Bhagat, Mael Manesse, Alison Bigley, Lorcan Sherry. Comparative multiplex digital phenotyping of the tumor microenvironment across multiple tumor types using a well characterized multi-tumor tissue microarray [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 2778.

Abstract 3878: Opposing CD68/CD163 tumour immune microenvironments revealed using a large multi-tumor tissue microarray (TMA) comprising cores from invasive margin (IM) and tumor center (TC)

Macrophages contribute to cancer-associated inflammation, and those with M2-like phenotype have been reported to be involved in tumor progression, immunosuppression, metastasis and angiogenesis. CD163 is considered a marker of M2-like macrophages/monocytes and high expression has been associated with poor prognosis in various tumor indications. To investigate the relative contribution of macrophage/monocyte cell populations to the tumor immune microenvironment across multiple tumor types concurrently, we have utilised a multi-tumor tissue microarray (TMA) comprising 30 different tumor indications, with approximately 12 cases per tumor type, each case represented by duplicate 1mm cores (1 from IM and 1 from TC). Serial sections of TMA slides (n=5) were stained by immunohistochemistry for CD68 and CD163, and cells/mm2/core delivered by digital image analysis of scanned images (CellProfilerTM). Comparative analysis of all tumor types regardless of core location (IM and TC combined) revealed lung, renal and cervical cancers to be the most highly infiltrated with CD68+ macrophages, while the greatest CD163 staining was observed for sarcoma and glioblastoma (GBM). Interestingly, a direct comparison of multiple tumor types simultaneously as performed here has revealed strongly opposing immune microenvironments in different tumor indications with respect to the balance of expression of CD68 and CD163. Higher frequencies of CD68+ macrophages relative to low CD163 expression was observed for prostate, endometrial, renal, cervical, thyroid, pancreatic, hepatic, small bowel and urothelial cancers. Conversely, a strong M2-like milieu exhibiting CD163+ cell frequencies exceeding CD68+ macrophages numbers was apparent for sarcoma, GBM, mesothelioma, bladder, cutaneous squamous cell carcinoma, gastrointestinal stromal tumor, head and neck squamous cell carcinoma, ER+ and Her2+ breast cancers. The remaining tumors, including cholangiocarcinoma, triple negative breast, lung, ovarian, gallbladder, colorectal, gastric, and esophageal cancers, all exhibited equivalent levels of infiltrating CD68+ and CD163+ cells. Analyses of IM versus TC revealed further complexities of the tumor immune microenvironment. For some disease settings, divergent CD163:CD68 ratios were observed for IM versus TC, whereas for other indications the ratio remained unchanged. In conclusion, concurrent analysis of multiple tumor indications for CD68 and CD163 has revealed immunosuppressive M2-like macrophage/monocyte tumor immune microenvironments that vary markedly between tumor types and within some tumors. These data may help to identify those patients that may benefit from therapies that target this immune pathway.

Citation Format: Marie Cumberbatch, Woo Ho Kim, Lorenzo Memeo, Lorenzo Colarossi, Christopher Womack, Milan Bhagat. Opposing CD68/CD163 tumour immune microenvironments revealed using a large multi-tumor tissue microarray (TMA) comprising cores from invasive margin (IM) and tumor center (TC) [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 3878.

Abstract 3194: Immune biomarkers in the tumor microenvironment associated with response in pre-treatment non-small cell lung cancer (NSCLC) samples with second line immunotherapy follow-up data

Surgical first line resection samples are frequently accessed to select patients for immune checkpoint inhibitor (ICI) therapy, often based on expression of PD-L1 measured by immunohistochemistry (IHC). However, while PD-L1 expression may enrich for response to ICIs, other immune parameters in the tumor microenvironment will likely contribute to outcome. To assist in the identification of biomarker(s) that might predict response to ICIs, we have analyzed a cohort of pre-treatment NSCLC cases for which second line immunotherapy clinical follow-up data are available. Formalin fixed paraffin embedded (FFPE) tumor samples were analysed (i) by single-plex IHC for CD3, CD8, CD68, CD163 and PD-L1, plus digital image analysis (CellProfilerTM), and (ii) profiled for multidimensional biomarkers using the targeted RNA sequencing and machine-learning platform ImmunoPrism® from Cofactor Genomics. Clinical follow-up data indicated objective response to ICI therapy for 4/18 patients, with average time from initial diagnosis to ICI treatment of 33.5 ± 29.6 months (mean ± SD). While CD68+ macrophage frequencies evaluated by IHC did not differ significantly between responder and non-responder populations, significant increases in T cell numbers (CD3: 2.3-fold; CD8: 2.7-fold; both p<0.05) were observed for the responder population. CD8 T cells were orthogonally measured using the ImmunoPrism assay, and the same significant differences for CD8 were observed. Although a trend towards decreased M2-like CD163+ macrophage/monocyte numbers was apparent by IHC for responders, this was not supported by the Cofactor analysis. When sections from the same FFPE block are analyzed across multiple commercially available platforms, there is high confidence for those signals which show concordance between platforms, such as the increase in CD8 T cell abundance observed for responders in this study. Moving beyond single-analyte biomarkers, a multidimensional biomarker combining immune escape genes and RNA-based immune cell measurements was generated using the ImmunoPrism platform with standard parameters. The resulting biomarker had the following performance characteristics: predictive accuracy, 89%; positive predictive value (PPV), 100%; negative predictive value (NPV), 88%; sensitivity, 50%; and specificity, 100%. A receiver-operating characteristic (ROC) curve was also generated for this putative biomarker, with an area under the curve (AUC) of 0.87. The promising results from this exploratory sample set warrant further investigation in a larger cohort. These data also demonstrate that clinical archives with well-curated demographic and outcome data, such as the FFPE samples analyzed here, provide excellent cohorts for biomarker screening and discovery studies. The application of new multianalyte approaches enables additional signals from the tumor microenvironment to be captured and included for predicting patient response.

Citation Format: Milan Bhagat, Woo Ho Kim, Lorenzo Memeo, Lorenzo Colarossi, Natalie LaFranzo, Steve Daniel, Christopher Womack, Marie Cumberbatch. Immune biomarkers in the tumor microenvironment associated with response in pre-treatment non-small cell lung cancer (NSCLC) samples with second line immunotherapy follow-up data [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 3194.

Association of immune microenvironment to response in treatment-naïve non-small cell lung cancer (NSCLC) samples with follow-up second-line immunotherapy data

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Background: Archival specimens collected months or years prior to starting immunotherapy are often used to identify patients for second line immune checkpoint inhibitor (ICI) treatment. PD-L1 expression and the immune microenvironment in these patients may have altered over time following multiple lines of failed standard of care (SOC) treatments. Methods: Formalin fixed paraffin embedded (FFPE) tumor samples, taken during resection performed as first line surgical treatment from a cohort of NSCLC patients (n = 18), were evaluated by Nanostring using the IO360 gene expression panel, and by immunohistochemistry (IHC) for CD3, CD8, PD-L1, CD68 and CD163. The resultant immune profiles were correlated with the clinical follow-up data for radiotherapy, SOC chemotherapy, and second line immunotherapy with the aim of understanding whether immune signatures predictive of response to ICI therapy may be identified in such samples. Results: Of the 18 cases, clinical follow-up data indicated objective response to ICI therapy for 4 patients, with the mean time from initial diagnosis to ICI treatment being 2.8 years (range: 0.4 to 8.5 years). Although pathologist PD-L1 IHC scores were not predictive of response, IHC image analysis data revealed significant increases in CD3 (2.3-fold) and CD8 (2.7-fold) T cell numbers in the responder population. In addition, although CD68+ macrophage frequencies did not differ significantly between responder and non-responder populations, reduced M2-like CD163+ macrophage/monocyte numbers were evident for responders. While the Tumor Inflammation Signature was not predictive of response, several gene expression signatures were significantly associated with response including increased abundance of CD8 T cells, cytotoxic cells, cytotoxicity, MHC class II antigen presentation and Melanoma-Associated Antigens (MAGE). Conclusions: Despite these patients having received various lines of radiotherapy and SOC chemotherapy prior to receiving immunotherapy, immune profiles associated with response to second line immunotherapy were detected in surgical first line resection samples.

Abstract S5-04: Low-fat dietary pattern and breast cancer overall survival in the women's health initiative dietary modification randomized controlled trial

Introduction: Among 48,835 postmenopausal women randomized in the Women's Health Initiative Dietary Modification (WHI DM) primary prevention trial, 1,767 women were diagnosed with breast cancer during the 8.3 years of dietary intervention. While differences were not statistically significant, there were fewer breast cancers diagnosed in the low fat dietary group women (HR 0.92 95% CI 0.84-1.01, P=0.09) with somewhat lower breast cancer mortality (HR 0.77 95% CI 0.48-1.22) than seen in control group women (JAMA 2006; 295:629). These findings were recently updated, and after 10.9 years (mean) post-diagnosis follow-up, breast cancer overall survival among these 1,767 women measured from diagnosis was greater in the dietary group (10 year survival, 82% vs 78%, 168 (2.24%) versus 319 (2.71%) deaths; HR 0.80 95% CI 0.66-0.97, P=0.02) (AACR Annual Meeting 2016, abstract CT0433, Clinical Trials Plenary Session). We now report low-fat dietary pattern influence on breast cancer overall survival in subgroups defined by breast cancer characteristics.

Methods: The WHI DM trial, conducted at 40 US clinical centers, from1993-1998 enrolled 48,835 postmenopausal women, aged 50-79, without prior breast cancer, with normal mammogram and dietary fat intake >32% of total energy. Participants were randomly assigned to a dietary intervention group (40%, n=19,541) with goals of fat intake reduction to 20% of energy and increased fruits, vegetables and grain intake, or a usual diet control group (60%, n=29,294). As previously reported, the dietary modification program reduced fat intake, increased fruit, vegetable and grain intake and was associated with modest weight loss (all P< 0.001). The current secondary analysis outcome is breast cancer overall survival in subgroups defined by breast cancer characteristics for cases diagnosed during the dietary intervention period. Because of possible selection prior to breast cancer diagnosis, these analyses do not compare randomized outcomes. Therefore, careful attention is paid to control of risk factors for breast cancer in the analysis.

Results: The examined subgroups included histology (ductal, lobular, other), estrogen receptor (ER) status (positive vs. negative by local laboratory), progesterone receptor (PR) status, HER2 status, triple negative (yes/no), stage (local, regional or distant), grade (well, moderately, poorly differentiated), tumor size (<1, 1- 2, >=2 cm), and nodal involvement (none, 1-3, 4+). None of the tests of interaction in subgroups were statistically significant. All subgroup hazard ratios (HR) were less than one except for ER negative cancers, triple negative cancers and those with 4+ positive lymph nodes. The results are suggestive of no influence of the low-fat dietary pattern on triple negative cancers (HR 1.64 95% CI 0.73-3.70 for triple negative vs. HR 0.73 95% CI 0.56-0.95 for other breast cancers, interaction P=0.06).

Conclusion: Compared to a usual diet control group, women randomized to a dietary intervention group providing a low-fat dietary pattern had a significantly increased overall survival following a breast cancer diagnosis with the possible exception of those developing triple negative cancers.

Citation Format: Chlebowski RT, Aragaki AK, Thomson CA, Anderson G, Manson JE, Simon MS, Rohan TE, Snetselar LG, Lane D, Barrington WE, Vitolins M, Womack C, Qi L, Hou L, Thomas F, Prentice RL. Low-fat dietary pattern and breast cancer overall survival in the women's health initiative dietary modification randomized controlled trial [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr S5-04.

Clinically Viable Gene Expression Assays with Potential for Predicting Benefit from MEK Inhibitors

Purpose: To develop a clinically viable gene expression assay to measure RAS/RAF/MEK/ERK (RAS-ERK) pathway output suitable for hypothesis testing in non-small cell lung cancer (NSCLC) clinical studies.Experimental Design: A published MEK functional activation signature (MEK signature) that measures RAS-ERK functional output was optimized for NSCLC in silico NanoString assays were developed for the NSCLC optimized MEK signature and the 147-gene RAS signature. First, platform transfer from Affymetrix to NanoString, and signature modulation following treatment with KRAS siRNA and MEK inhibitor, were investigated in cell lines. Second, the association of the signatures with KRAS mutation status, dynamic range, technical reproducibility, and spatial and temporal variation was investigated in NSCLC formalin-fixed paraffin-embedded tissue (FFPET) samples.Results: We observed a strong cross-platform correlation and modulation of signatures in vitro Technical and biological replicates showed consistent signature scores that were robust to variation in input total RNA; conservation of scores between primary and metastatic tumor was statistically significant. There were statistically significant associations between high MEK (P = 0.028) and RAS (P = 0.003) signature scores and KRAS mutation in 50 NSCLC samples. The signatures identify overlapping but distinct candidate patient populations from each other and from KRAS mutation testing.Conclusions: We developed a technically and biologically robust NanoString gene expression assay of MEK pathway output, compatible with the quantities of FFPET routinely available. The gene signatures identified a different patient population for MEK inhibitor treatment compared with KRAS mutation testing. The predictive power of the MEK signature should be studied further in clinical trials. Clin Cancer Res; 23(6); 1471-80. ©2016 AACRSee related commentary by Xue and Lito, p. 1365.

Changes in bone mineral density over time by body mass index in the health ABC study

Obesity appears protective against osteoporosis in cross-sectional studies. However, results from this longitudinal study found that obesity was associated with bone loss over time. Findings underscore the importance of looking at the longitudinal relationship, particularly given the increasing prevalence and duration of obesity among older adults.

INTRODUCTION

Cross-sectional studies have found a positive association between body mass index (BMI) and bone mineral density (BMD), but little is known about the longitudinal relationship in US older adults.

METHODS

We examined average annual rate of change in BMD by baseline BMI in the Health, Aging, and Body Composition Study. Repeated measurement of BMD was performed with dual-energy X-ray absorptiometry (DXA) at baseline and years 3, 5, 6, 8, and 10. Multivariate generalized estimating equations were used to predict mean BMD (femoral neck, total hip, and whole body) by baseline BMI (excluding underweight), adjusting for covariates.

RESULTS

In the sample (n = 2570), 43 % were overweight and 24 % were obese with a mean baseline femoral neck BMD of 0.743 g/cm(2), hip BMD of 0.888 g/cm(2), and whole-body BMD of 1.09 g/cm(2). Change in total hip or whole-body BMD over time did not vary by BMI groups. However, obese older adults lost 0.003 g/cm(2) of femoral neck BMD per year more compared with normal weight older adults (p < 0.001). Femoral neck BMD change over time did not differ between the overweight and normal weight BMI groups (p = 0.74). In year 10, adjusted femoral neck BMD ranged from 0.696 g/cm(2) among obese, 0.709 g/cm(2) among normal weight, and 0.719 g/cm(2) among overweight older adults.

CONCLUSIONS

Findings underscore the importance of looking at the longitudinal relationship between body composition and bone mineral density among older adults, indicating that high body mass may not be protective for bone loss over time.

Leptin, BMI, and a Metabolic Gene Expression Signature Associated with Clinical Outcome to VEGF Inhibition in Colorectal Cancer

VEGF (vascular endothelial growth factor) signaling inhibitors are widely used in different cancer types; however, patient selection remains a challenge. Analyses of samples from a phase III clinical trial in metastatic colorectal cancer testing chemotherapy versus chemotherapy with the small molecule VEGF receptors inhibitor cediranib identified circulating leptin levels, BMI, and a tumor metabolic and angiogenic gene expression signature associated with improved clinical outcome in patients treated with cediranib. Patients with a glycolytic and hypoxic/angiogenic profile were associated with increased benefit from cediranib, whereas patients with a high lipogenic, oxidative phosphorylation and serine biosynthesis signature did not gain benefit. These findings translated to pre-clinical tumor xenograft models where the same metabolic gene expression profiles were associated with in vivo sensitivity to cediranib as monotherapy. These findings suggest a link between patient physiology, tumor biology, and response to antiangiogenics, which may guide patient selection for VEGF therapy in the future.

First-in-Human Pharmacokinetic and Pharmacodynamic Study of the Dual m-TORC 1/2 Inhibitor AZD2014

PURPOSE

AZD2014 is a novel, oral, m-TORC 1/2 inhibitor that has shown in vitro and in vivo efficacy across a range of preclinical human cancer models.

EXPERIMENTAL DESIGN

A rolling six-dose escalation was performed to define an MTD (part A), and at MTD a further cohort of patients was treated to further characterize toxicities and perform pre- and posttreatment biopsies (part B). AZD2014 was administered orally twice a day continuously. Flow cytometry, ELISA, and immunohistochemistry were used to quantify pharmacodynamic biomarkers. Pharmacokinetic analysis was carried out by mass spectrometry.

RESULTS

A total of 56 patients were treated across a dose range of 25 to 100 mg. The MTD was 50 mg twice daily. The dose-limiting toxicities were fatigue and mucositis. At the MTD, the most common adverse events (AE) were fatigue (78%), nausea (51%), and mucositis (49%), but these were equal to or greater than grade 3 in only 5% of patients. Drug levels achieved at the MTD (AUC SS: 6686 ng·h/mL, Cmax ss 1,664 ng/mL) were consistent with activity in preclinical models. A reduction in p-S6 levels and Ki67 staining was observed in 8 of 8 and 5 of 9 evaluable paired biopsy samples. Partial responses were seen in a patient with pancreatic cancer and a patient with breast cancer, who were found to have a PDGFR and ERBB2 mutation, respectively.

CONCLUSIONS

The recommended phase II dose for further evaluation of AZD2014 is 50 mg twice daily, and at this dose it has been possible to demonstrate pharmacologically relevant plasma concentrations, target inhibition in tumor, and clinical responses.

The association between vitamin K status and knee osteoarthritis features in older adults: the Health, Aging and Body Composition Study

BACKGROUND

Vitamin K-dependent (VKD) proteins, including the mineralization inhibitor matrix-gla protein (MGP), are found in joint tissues including cartilage and bone. Previous studies suggest low vitamin K status is associated with higher osteoarthritis (OA) prevalence and incidence.

OBJECTIVE

To clarify what joint tissues vitamin K is relevant to in OA, we investigated the cross-sectional and longitudinal association between vitamin K status and knee OA structural features measured using magnetic resonance imaging (MRI).

METHODS

Plasma phylloquinone (PK, vitamin K1) and dephosphorylated-uncarboxylated MGP ((dp)ucMGP) were measured in 791 older community-dwelling adults who had bilateral knee MRIs (mean ± SD age = 74 ± 3 y; 67% female). The adjusted odds ratios (and 95% confidence intervals) [OR (95%CI)] for presence and progression of knee OA features according to vitamin K status were calculated using marginal models with generalized estimating equations (GEEs), adjusted for age, sex, body mass index (BMI), triglycerides and other pertinent confounders.

RESULTS

Longitudinally, participants with very low plasma PK (<0.2 nM) were more likely to have articular cartilage and meniscus damage progression after 3 years [OR (95% CIs): 1.7(1.0-3.0), 2.6(1.3-5.2) respectively] compared to sufficient PK (≥ 1.0 nM). Higher plasma (dp)ucMGP (reflective of lower vitamin K status) was associated with higher odds of meniscus damage, osteophytes, bone marrow lesions, and subarticular cysts cross-sectionally [ORs (95% CIs) comparing highest to lowest quartile: 1.6(1.1-2.3); 1.7(1.1-2.5); 1.9(1.3-2.8); 1.5(1.0-2.1), respectively].

CONCLUSION

Community-dwelling men and women with very low plasma PK were more likely to have progression of articular cartilage and meniscus damage. Plasma (dp)ucMGP was associated with presence of knee OA features but not progression. Future studies are needed to clarify mechanisms underlying vitamin Ks role in OA.

Abstract 3670: Toll-like receptor (TLR) 7 expression in the human tumor microenvironment

Following the success of imiquimod, agents targeting TLR7 are being progressed as potential immunotherapeutics. Stimulation of TLR7 initiates a plasmacytoid dendritic cell driven immune response which drives efficacy. In addition to a role in regulating immune cell responses, TLR7 has also been reported to play a role in regulating tumor cell function (1,2).

To investigate the expression of TLR7, by both tumor cells and by tumor infiltrating immune cells, we have used immunohistochemistry (IHC). Initially, a comprehensive validation of commercially available anti-TLR7 antibodies was conducted revealing one antibody (Epitomics, 3923-1) with specificity for TLR7 in western blots of cell lysates, and by immunocytochemistry of formalin fixed paraffin embedded (FFPE) cell pellets, of HEK293 cells stably transfected with TLR7, mock-transfected or non-transfected. 3923-1 was validated further for IHC across FFPE sections of human spleen, lymph node and tonsil demonstrating expected tissue and cellular localization. A comparison of staining for TLR7 in whole sections of FFPE tumors revealed non-specific tumor staining using antibodies that failed the validation process compared with the staining pattern observed for 3923-1.

Subsequently, five tissue microarrays (TMAs) comprising 18 different human tumor types (6-25 patients/tumor type, triplicate cores) and 14 normal tissues (5 donors/tissue type, duplicate cores) were stained by IHC for TLR7 expression using 3923-1. Pathologist scores for tumor cells revealed 5/18 tumor types negative for TLR7 (ovarian, glioma, thyroid, liver, renal) and 9/18 tumor types with a proportion of patients (4%-36%) exhibiting weak (1+) staining (breast, lung, colorectal, pancreatic, gastric, head & neck, melanoma, esophageal, endometrial). Furthermore, 11-17% of sarcoma, prostate and bladder tumors displayed moderate (2+) staining for TLR7, whereas corresponding normal tissue epithelium was largely negative for TLR7. Importantly, an increased density of immune infiltrates was observed in tumor tissues compared with normal tissues, and a greater proportion of the immune infiltrate in tumors was TLR7 positive. The conclusion drawn is that TLR7 may be less frequently expressed by tumor cells than reported previously and that tumors exhibit a marked TLR7 positive immune cell infiltrate. These data identify tumour types which might benefit from TLR7 therapy and may guide patient selection.

1. Grimm M et al. Eur J Cancer (2010):2849-57.

2. Cherfils-Vicini J et al. J Clin Invest (2010):1285-97.

Citation Format: Nicola Haughton, Foster Emily, Christopher Womack, Simon Barry, Setsuko Yamamoto, Masashi Murata, Marie Cumberbatch. Toll-like receptor (TLR) 7 expression in the human tumor microenvironment. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 3670. doi:10.1158/1538-7445.AM2014-3670

A phase I trial of vertical inhibition of IGF signalling using cixutumumab, an anti-IGF-1R antibody, and selumetinib, an MEK 1/2 inhibitor, in advanced solid tumours

BACKGROUND

We completed a phase I clinical trial to test the safety and toxicity of combined treatment with cixutumumab (anti-IGF-1R antibody) and selumetinib (MEK 1/2 inhibitor).

METHODS

Patients with advanced solid tumours, refractory to standard therapy received selumetinib hydrogen sulphate capsules orally twice daily, and cixutumumab intravenously on days 1 and 15 of each 28-day cycle. The study used a 3+3 design, with a dose-finding cohort followed by an expansion cohort at the maximally tolerated dose that included pharmacokinetic and pharmacodynamic correlative studies.

RESULTS

Thirty patients were enrolled, with 16 in the dose-finding cohort and 14 in the expansion cohort. Grade 3 or greater toxicities included nausea and vomiting, anaemia, CVA, hypertension, hyperglycaemia, and ophthalmic symptoms. The maximally tolerated combination dose was 50 mg twice daily of selumetinib and 12 mg kg(-1) every 2 weeks of cixutumumab. Two patients achieved a partial response (one unconfirmed), including a patient with BRAF wild-type thyroid carcinoma, and a patient with squamous cell carcinoma of the tongue, and six patients achieved time to progression of >6 months, including patients with thyroid carcinoma, colorectal carcinoma, and basal cell carcinoma. Comparison of pre- and on-treatment biopsies showed significant suppression of pERK and pS6 activity with treatment.

CONCLUSIONS

Our study of anti-IGF-1R antibody cixutumumab and MEK 1/2 inhibitor selumetinib showed that the combination is safe and well-tolerated at these doses, with preliminary evidence of clinical benefit and pharmacodynamic evidence of target inhibition.

FGFR2 amplification has prognostic significance in gastric cancer: results from a large international multicentre study

BACKGROUND

In preclinical gastric cancer (GC) models, FGFR2 amplification was associated with increased tumour cell proliferation and survival, and drugs targeting this pathway are now in clinical trials.

METHODS

FGFR2 FISH was performed on 961 GCs from the United Kingdom, China and Korea, and the relationship with clinicopathological data and overlap with HER2 amplification were analysed.

RESULTS

The prevalence of FGFR2 amplification was similar between the three cohorts (UK 7.4%, China 4.6% and Korea 4.2%), and intratumoral heterogeneity was observed in 24% of FGFR2 amplified cases. FGFR2 amplification was associated with lymph node metastases (P<0.0001). FGFR2 amplification and polysomy were associated with poor overall survival (OS) in the Korean (OS: 1.83 vs 6.17 years, P=0.0073) and UK (OS: 0.45 vs 1.9 years, P<0.0001) cohorts, and FGFR2 amplification was an independent marker of poor survival in the UK cohort (P=0.0002). Co-amplification of FGFR2 and HER2 was rare, and when high-level amplifications did co-occur these were detected in distinct areas of the tumour.

CONCLUSION

A similar incidence of FGFR2 amplification was found in Asian and UK GCs and was associated with lymphatic invasion and poor prognosis. This study also shows that HER2 and FGFR2 amplifications are mostly exclusive.

A matrix approach to guide IHC-based tissue biomarker development in oncology drug discovery

Immunohistochemistry (IHC) is a core platform for the analysis of tissue samples, and there is an increasing demand for reliable and quantitative IHC-based tissue biomarkers in oncology clinical research and development (R&D) environments. Biomarker assay and drug development proceed in parallel. Furthermore, biomarker assay requirements change with each phase of drug development. We have therefore developed a matrix tool to enable researchers to evaluate whether a particular IHC biomarker assay is fit for purpose. Experience gained from the development of 130 IHC biomarkers, supporting a large number of oncology drug projects, was used to formulate a practical approach to IHC assay development. The resultant matrix grid and accompanying work flow incorporates 16 core decision points that link antibody and assay specificity and sensitivity, and assay performance in preclinical and clinical samples, with stages of drug development. The matrix provides a means to ensure that relevant information on an IHC assay in development is recorded and communicated consistently and that minimum assay validation requirements are met.

Human biological sample biobanking to support tissue biomarkers in pharmaceutical research and development

Advances in the understanding of molecular pathology and thereby the mechanisms that could be amenable to therapeutic manipulation are the reason that pharmaceutical research and development is focused increasingly on measurement of molecular biomarkers in human biological samples. Obtaining direct or indirect access to sufficient samples that are fit for research purposes can be a major challenge. A biobanking infrastructure has a significant role in the acquisition, storage and usage of human biological samples and here we review some key requirements for establishing a biobank. These include ensuring; that appropriate governance mechanisms are in place, that samples available are appropriate and fit for the intended research purposes that the infrastructure is sustainable in the future and that use of the biobank assets meets the strategic aims of the host organisation. Finally we present a case study--the STRATUM project which has recently completed and through a collaborative approach involving six industry and public partners drawing on a network of experts, examined biobank policies, public attitudes to biobanking, donor consent, sample and data standards, technical requirements for a register and biobanking financial models, albeit from a UK perspective.

Concordance of ATM (ataxia telangiectasia mutated) immunohistochemistry between biopsy or metastatic tumor samples and primary tumors in gastric cancer patients

ATM (ataxia telangiectasia mutated) is one of several DNA repair proteins that are suggested to sensitize tumor cells to the poly(ADP-ribose) polymerase inhibitor olaparib when deficient. The aim of this study was to assess the spatiotemporal concordance of ATM immunohistochemistry (IHC) in gastric cancer in order to determine if measurements made at the level of various sample types and times could be inferred as having the potential to be relevant to treatment decisions made at the patient level. Two independent cohorts composed of 591 gastric cancer patients divided into a gastrectomy cohort (n = 450) and a metastasis cohort (n = 141) were used in this study. A total of 2,705 ATM IHC samples were examined, including 450 whole tissue, 3 sets of 450 tissue microarray (TMA), 301 biopsy, 222 metastatic tumor and 2 additional whole tissue samples of 50 cases from the gastrectomy cohort, and 141 pairs of primary and metastatic tumors from the metastasis cohort. The prevalence of ATM negativity was 13.1% in biopsies, 13.9, 15.1, and 16.0% in TMAs and 15.9% in whole tissue samples of the gastrectomy cohort, and 21.4% in primary tumor and 21.5% in metastatic tumor samples of the metastasis cohort. coefficients were 0.341 for biopsy, 0.572 as the average of 3 TMAs and 0.415 for the largely synchronous metastatic tumors of the gastrectomy cohort, and 0.153 for the largely asynchronous metastatic tumors of the metastasis cohort. Using whole tissue sections from tumor resections or primary tumor, respectively, as the reference standards, specificity and sensitivity were 91.6 and 41.0% for biopsy, 93.9 and 61.9% as the average of 3 TMAs, and 86.6 and 58.8% for metastatic tumors of the gastrectomy cohort and 81.7 and 33.3% for metastatic tumors of the metastasis cohort, respectively. Although we have demonstrated that the IHC assay for ATM was robust and reproducible in gastric tumor samples, we have also found that measurements were subject to significant discordance across multiple sample types from the same patient. Further work will be necessary to determine if classification may be made more consistent by multiple sampling. However, the lack of agreement between primary and asynchronous metastatic samples suggests that such sampling would need to be performed at the time of any treatment decision.

Abstract 5635: Analysis of monocarboxylate transporter 4 as a biomarker shows prognostic significance as an indicator of radiotherapy in squamous cell carcinoma of the head and neck

BACKGROUND: Hypoxia is known to contribute significantly to tumor progression and resistance to radiotherapy, decreasing local tumor control and lowering the rates of disease free and overall survival. Research to target hypoxia in the clinic has produced varying results; hence the discovery of hypoxia markers has become more significant. Monocarboxylate Transporter 4 (MCT4) is a hypoxia-regulated transporter of lactate out of the cell, preventing its intra-cellular accumulation, enabling sustained high glycolytic rates and maintenance of intra-cellular pH.

AIM: To evaluate MCT4 immunohistochemically as a potential biomarker for prognosis of patients with head and neck squamous cell carcinoma (SCC) of tonsil or tongue undergoing radiotherapy, and to determine the impact of MCT4 expression on radiotherapy resistance.

METHODS: 155 histologically confirmed SCC pre-treatment diagnostic biopsies, originating from the tonsil or posterior third of the tongue, were collected retrospectively from a diagnostic archive. The biopsies were analyzed immunohistochemically to evaluate MCT4 membrane expression. MCT4 expression was assessed in a double blind study using a semi-quantitative scoring system. Scores were analyzed for possible correlations with clinicopathological data relating to outcome 5 years post diagnosis, where all patients had received radiotherapy to the primary site. siRNA against MCT4 was used in SCC cell lines to evaluate radiosensitivity of wild-type and MCT4-knockdown cells by colony forming assays.

RESULTS: A univariate analysis to assess high MCT4 expression (top 25% of scores) vs low MCT4 expression (lower 75%) showed that MCT4 is a significant adverse prognostic factor in the series of biopsies. High MCT4 expression correlates with poor loco-regional control (p = 0.017), reduced cancer-specific survival (p = 0.02) and reduced overall survival (p = 0.055). In a multivariate analysis high MCT4 expression retained prognostic significance for poor loco-regional control (p = 0.007). This was confirmed by clonogenic assay in FaDu and PE/CA-PJ-34 cell lines, MCT4-knockdown cells showed a marked increase in radiosensitivity compared to wild-type cells.

CONCLUSIONS: MCT4 is a significant biomarker for prognosis and treatment outcome following radiotherapy in SCC of tonsil and tongue. The increase in significance from overall survival to loco-regional control is consistent with a hypoxia-regulated marker of radiotherapy resistance. The functional role of MCT4 as a lactate transporter in hypoxia may be of key underlying biological importance to this finding, maintaining intracellular pH in an hypoxic microenvironment. This suggests that drug inhibition of MCT4 may potentially sensitize tumor cells to radiation treatment.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 5635.

Quantitative multiplexed quantum dot immunohistochemistry

Quantum dots are photostable fluorescent semiconductor nanocrystals possessing wide excitation and bright narrow, symmetrical, emission spectra. These characteristics have engendered considerable interest in their application in multiplex immunohistochemistry for biomarker quantification and co-localisation in clinical samples. Robust quantitation allows biomarker validation, and there is growing need for multiplex staining due to limited quantity of clinical samples. Most reported multiplexed quantum dot staining used sequential methods that are laborious and impractical in a high-throughput setting. Problems associated with sequential multiplex staining have been investigated and a method developed using QDs conjugated to biotinylated primary antibodies, enabling simultaneous multiplex staining with three antibodies. CD34, Cytokeratin 18 and cleaved Caspase 3 were triplexed in tonsillar tissue using an 8h protocol, each localised to separate cellular compartments. This demonstrates utility of the method for biomarker measurement enabling rapid measurement of multiple co-localised biomarkers on single paraffin tissue sections, of importance for clinical trial studies.

Src inhibitors in early breast cancer: a methodology, feasibility and variability study

Early clinical trials of anticancer agents may be enriched by robust biomarkers of activity. Surrogate measures used in trials of cytotoxic agents, such as tumor size regression, may not be informative when investigating targeted agents that act principally to inhibit invasion or proliferation. This study aimed to determine the validity of invasion-related biomarkers of activity for AZD0530, a potent Src inhibitor currently in clinical development. Focal adhesion kinase (FAK) and paxillin are downstream phosphorylation substrates of Src and mediate tumor cell adhesion and invasiveness. These were therefore selected as biologically relevant markers of Src inhibition. Early breast cancer was chosen as a model as multiple samples can be collected during standard treatment and there is an intervening period in which experimental intervention can be applied. Tumor tissue was collected from diagnostic core biopsies and subsequent surgical tumor excision samples in 29 women with early breast cancer attending a single center. Protein levels were assessed quantitatively by Luminex and qualitatively by immunohistochemistry. AZD0530 inhibited tumor growth in a manner independent of dose and inhibited phosphorylation of FAK and paxillin in a dose-dependent manner in a Calu-6 xenograft model. In the clinical study, agreement of within-visit and also of between-visit measurements was high and the estimated number of patients required to detect a drug effect would be low enough to allow use of these markers as endpoints in future dose selection studies.

Providing Human Tissue for Research: 1996–2006

This article details the authors' experience establishing infrastructure for tissue collection, storage and distribution for biomedical research, firstly within a public healthcare service and latter in the pharmaceutical industry. Access to human tissue in the context of public-private collaboration in research and development is essential to the provision of high-quality medicines and healthcare and is now supported by a new legal framework in England and Wales. Through collaborations there are opportunities for mutual benefit for patients and professionals alike. Attention to the wishes of tissue donors through informed consent at the outset ensured confidence and continued activity when so-called 'organ retention scandals' emerged midway through this period. The overwhelming majority of potential donors support the use of their tissues in biomedical research irrespective of where the research is carried out.

Effects of a maximal exercise test on neurocognitive function

OBJECTIVE

To examine the effects of a maximal exercise test on cognitive function in recreational athletes.

DESIGN

A repeated-measures design was used to compare baseline with post-cognitive function and fatigue symptoms after a maximal exercise test.

SETTING

Division 1 American Midwestern University, (Michigan State University, Michigan, USA).

PARTICIPANTS

102 male and female recreational athletes.

INTERVENTION

Participants in the experimental group (n = 54) were asked to perform a maximal treadmill exercise test to maximal oxygen uptake (VO2 max). Participants in the control group were asked to rest for 15 min.

MAIN OUTCOME MEASUREMENTS

All participants were administered a neuropsychological test battery called Immediate Post-Concussion Assessment and Cognitive Testing (ImPACT) before and after exercise to measure neurocognitive function and fatigue symptoms.

RESULTS

Results revealed a significant group (control, experimental) x time (baseline, post-test 1, post-test 2) interaction for verbal memory composite scores (p = 0.025). Specifically, verbal memory composite scores decreased in the experimental group from baseline to post-test 1 (p = 0.00). These values returned to baseline 3 days after the VO2 max test (p = 0.00). Further analysis on verbal memory composite scores demonstrated significant differences on immediate recall memory (p = 0.00) and delayed recall memory (p = 0.00). No significant differences were observed for visual memory (p = 0.54), motor processing speed (p = 0.68) and reaction time (p = 0.44) composite scores between the experimental and control groups.

CONCLUSION

The results of this study suggest that a maximal exercise test attenuated a limiting effect on cognitive function. When utilising a neuropsychological test battery to evaluate a patient who has sustained a head injury, the test should not be administered immediately after a practice or a game session.

Supply and use of human tissue for research purposes: survey of BATB affiliated tissue banks

This paper describes a survey undertaken to identify the extent of supply and use of human tissue in research by BATB affiliated tissue banks. Approximately one third of tissue banks registered with the BATB are currently supplying samples that are found to be unsuitable for clinical use, for research. These banks all obtain consent for research and all supply tissue for in-house research. Some tissue is transferred to other public and commercial institutions. A harmonised network approach is proposed as the way forward to meet the increasing demand for human tissue in research.

Cadaveric tissue retrieval service for research: one-year review and options for the future

The Tissue Acquisition Unit at Peterborough has an established service for collecting cadaveric human tissue for research. A one-year, on-going, in-house review was undertaken to evaluate the cost- and time-effectiveness of the service. The review identified referrals that failed to result in post mortem tissue retrieval. Only 28.6% of potential donors referred to the Unit led to successful tissue retrieval and the main reason for failure was post mortem time delay in some cases related to distance of location of the body from the Unit. The evolving novel role of the Pathology Liaison Nurses in the Unit is expected to increase the proportion of tissue acquisition from the local population and provide a more efficient service for donors and their families and researchers who use human tissue.

Challenges in the Testing of Non-Heart-Beating Cadavers for Viral Markers: Implications for the Safety of Tissue Donors

Natural changes that occur in blood and tissue after death may result in false positive results in antigen and antibody detection tests performed to identify markers of viral infection in potential tissue donors. Such tissue, which might otherwise be acceptable for therapeutic purposes, would not meet current standards for safe tissue banking. This is especially important in the context of insufficiency in the tissue supply. In this study, a series of blood samples collected during routine post-mortem examination was assayed using a range of commercially available kits for the detection of HBsAg, anti-HCV and anti-HIV 1 + 2 antibody/antigen. Results of tests on 104 samples collected from 97 individuals indicate that some kits result in a higher number of initial reactive samples than others. Approximately 40% of samples were reactive in one or more HBsAg assay, less than 10% in at least one anti-HIV kit and only 1 sample at low level on an anti-HCV kit. Liver or lymph node samples from individuals whose serum sample gave reactive results in antigen/antibody assays were tested for viral nucleic acid in the corresponding nucleic acid amplification test. Only one individual's sample was confirmed to test positive for HBsAg in a confirmatory neutralisation test and by nucleic acid amplification technology, and a second individual whose serum was scored reactive for anti-HCV, but negative for HBsAg, had a liver sample which was HBV DNA positive and HCV RNA negative. The results of the study indicate that antibody/antigen assays are not as specific as NAT using state of the art DNA extraction techniques. Both types of assay complement each other and used together will help assure the safety of tissues for transplantation.

The research potential of tissue from a cadaveric donor

The purpose of this case report is to illustrate the research potential of the tissue obtained from a single donor referred to the Peterborough Hospitals NHS Trust (PHNHST) Research Tissue Bank. Tissue retrieval was done 19 hours after death and 453 tissue units processed on site were despatched to 20 mainly commercial client research organisations.

Appendicular fractures: a significant problem among institutionalized adults with developmental disabilities

A high incidence of nontraumatic fracture in adults with developmental disabilities living in a state-run facility was described. Risk factors for fracture, including bone mineral density (BMD), were investigated to determine whether people at highest risk for fracture could be prospectively identified. There was a 7.3% incidence of fracture among 391 adults. Risk factors were examined for 23 residents with fracture and 23 age-, race-, and gender-matched controls. There was a trend for antiepileptic medication usage to be associated with fractures. Estimated BMD by heel ultrasound did not predict fracture; however, values were much lower than those for the general population. Fractures and low BMD are significant problems among institutionalized adults with severe developmental disabilities. Further studies to identify therapies to prevent fractures are warranted.

How much tissue is present in archival paraffin blocks and slides?

In order to inform the debate about tissue blocks and slides introduced by the Retained Organs Commission, a study is undertaken to determine the percentage weight of tissue present in the surgical archive in the cellular pathology department of a district general hospital. When original, unprocessed tissue weight is expressed as a percentage, based on the weight of 100 archival paraffin blocks, values range from 0.2% to 41.5%. When the corresponding archival slides are also included, the values fall as low as 0.1% (i.e. up to 99.9% of the stored archival material for a piece of processed tissue could be non-human material). The results are used to make a case for including archival histological material as part of the patient's clinical record, although it is accepted that this study was performed only on surgical tissue.