Diana Lenzner

PD-1 Is a Regulator of NY-ESO-1-Specific CD8+ T Cell Expansion in Melanoma Patients

The programmed death 1 (PD-1) receptor is a negative regulator of activated T cells and is up-regulated on exhausted virus-specific CD8+ T cells in chronically infected mice and humans. Programmed death ligand 1 (PD-L1) is expressed by multiple tumors, and its interaction with PD-1 resulted in tumor escape in experimental models. To investigate the role of PD-1 in impairing spontaneous tumor Ag-specific CD8+ T cells in melanoma patients, we have examined the effect of PD-1 expression on ex vivo detectable CD8+ T cells specific to the tumor Ag NY-ESO-1. In contrast to EBV, influenza, or Melan-A/MART-1-specific CD8+ T cells, NY-ESO-1-specific CD8+ T cells up-regulated PD-1 expression. PD-1 up-regulation on spontaneous NY-ESO-1-specific CD8+ T cells occurs along with T cell activation and is not directly associated with an inability to produce cytokines. Importantly, blockade of the PD-1/PD-L1 pathway in combination with prolonged Ag stimulation with PD-L1+ APCs or melanoma cells augmented the number of cytokine-producing, proliferating, and total NY-ESO-1-specific CD8+ T cells. Collectively, our findings support the role of PD-1 as a regulator of NY-ESO-1-specific CD8+ T cell expansion in the context of chronic Ag stimulation. They further support the use of PD-1/PD-L1 pathway blockade in cancer patients to partially restore NY-ESO-1-specific CD8+ T cell numbers and functions, increasing the likelihood of tumor regression.

Combined Analysis of Estrogen Receptor β-1 and Progesterone Receptor Expression Identifies Lung Cancer Patients with Poor Outcome

Purpose: Steroid hormones and growth factors affect lung cancer, and it is possible they act in concert to influence patient outcome. Experimental Design: Primary lung tumors and normal lung tissue were analyzed for expression and localization of estrogen receptor α and β-1 (ERα and ERβ), aromatase, progesterone receptor (PR), and epidermal growth factor receptor (EGFR). Results: Tumors expressed higher levels of ERβ compared to matched normal lung, whereas the reverse was true of PR. High cytoplasmic ERβ expression was identified as an independent negative prognostic predictor of overall survival (OS; HR = 1.67), and low total PR was identified as an independent negative predictor of time to progression (TTP; HR = 1.59). After adjusting for stage, age, sex, and smoking, combined high cytoplasmic ERβ and low total PR showed enhanced effects on OS (HR = 2.64) and on TTP (HR = 6.02). Further effects on OS were observed when EGFR expression was included (HR = 5.32). Patients with low cytoplasmic ERβ, low aromatase, low EGFR, and high total PR had shorter OS than patients with the opposite pattern (HR = 6.60). Contribution of these markers to survival showed no significant sex differences in a multivariable model. ERα was elevated in tumors but was not predictive of survival, and appears to represent a variant ERα protein that is only recognized by a C-terminal antibody. Conclusions: Hormonal and EGFR pathways together may contribute to lung cancer prognosis. Lung tumors with high ERβ-1/low PR may define patients with aggressive biology. A validation study is necessary to fully assess the predictive value of these markers. Clin Cancer Res; 17(1); 154–64. ©2010 AACR.

Estrogen Receptor β Functions through Nongenomic Mechanisms in Lung Cancer Cells

Recent studies have shown that estrogens promote the growth of lung cancer cells and may potentially be responsible for increased susceptibility to lung cancer in women. These observations raise the possibility of using antiestrogens in treating and preventing lung cancer. However, it is not clear how estrogen receptors (ERs) modulate the growth of non-small cell lung cancer (NSCLC) cells. Our Western blotting and real-time PCR analysis showed that NSCLC cells expressed ERbeta, but not ERalpha. In addition, ERbeta-specific ligands, but not ERalpha-specific ligands, promoted the growth of lung cancer cells. Furthermore, knockdown of ERbeta by short hairpin RNA constructs resulted in loss of estrogen-dependent growth of lung cancer cells. Interestingly, endogenous ERbeta failed to transcriptionally activate estrogen response element (ERE)-luciferase constructs in NSCLC cells, suggesting a lack of genomic function. Upon further investigation, ERbeta was found to be in the cytoplasm in all lung cancer cells and failed to translocate to the nucleus in the presence of estrogen, as observed by biochemical, ArrayScan, and confocal microscopy experiments. Nonetheless, estrogen caused rapid activation of cAMP, Akt, and MAPK signaling pathways in lung cancer cells. Immunohistochemical analysis of lung tumor biopsies showed strong ERbeta staining in the cytoplasm, whereas no staining was observed for ERalpha. In conclusion, our results suggest that that proliferative effects of estrogen in lung cancer cells is mediated primarily, if not exclusively, by the nongenomic action of ERbeta.

Long-term results of chemoimmunotherapy with low-dose fludarabine, cyclophosphamide and high-dose rituximab as initial treatment for patients with chronic lymphocytic leukemia.

To the editor: Chemoimmunotherapy with fludarabine (F), cyclophosphamide (C), and rituximab (R) is currently considered the gold standard first-line therapy for chronic lymphocytic leukemia (CLL).[1][1] In an attempt to reduce the neutropenia and maintain the high response rate of standard-dose FCR

Nuclear vitamin D receptor expression is associated with improved survival in non-small cell lung cancer.

Vitamin D has been shown to have anti-proliferative effects in a wide variety of cancers including lung cancer. The anticancer effects of vitamin D are mediated primarily by its active metabolite, 1,25-dihydroxyvitamin D (calcitriol), through vitamin D receptor (VDR) signaling. However, thus far there have been no studies evaluating the association between VDR expression and survival outcome in lung cancer. Using immunohistochemical analysis, we evaluated VDR expression, separately in the nucleus and cytoplasm, in lung cancer samples from 73 non-small cell lung carcinoma (NSCLC) patients with no prior therapy, and investigated the association between VDR expression and overall survival (OS). Cox proportional hazard models were used for our primary analyses. There were 44 deaths during a median follow-up of 51 months (range 13-93 months). High nuclear VDR expression was associated with improved OS after adjusting for age, gender, stage, smoking status, and histology (adjusted hazard ratio, 0.36; 95% confidence interval, 0.17-0.79). There was no association between cytoplasmic VDR expression and OS. Our results suggest that nuclear VDR status may be a prognostic marker in NSCLC. Future large studies to replicate our findings and to assess the impact of VDR gene polymorphisms on VDR expression are required as therapies targeting the vitamin D signaling pathway may be influenced by VDR status in the target lung cancer tissue.

Targeting of Both the c-Met and EGFR Pathways Results in Additive Inhibition of Lung Tumorigenesis in Transgenic Mice.

EGFR and c-Met are both overexpressed in lung cancer and initiate similar downstream signaling, which may be redundant. To determine how frequently ligands that initiate signaling of both pathways are found in lung cancer, we analyzed serum for hepatocyte growth factor (HGF), transforming growth factor-alpha, and amphiregulin (AREG) in lung cancer cases and tobacco-exposed controls. HGF and AREG were both significantly elevated in cases compared to controls, suggesting that both HGF/c-Met and AREG/EGFR pathways are frequently active. When both HGF and AREG are present in vitro, downstream signaling to MAPK and Akt in non-small cell lung cancer (NSCLC) cells can only be completely inhibited by targeting both pathways. To test if dual blockade of the pathways could better suppress lung tumorigenesis in an animal model than single blockade, mice transgenic for airway expression of human HGF were treated with inhibitors of both pathways alone and in combination after exposure to a tobacco carcinogen. Mean tumor number in the group using both the HGF neutralizing antibody L2G7 and the EGFR inhibitor gefitinib was significantly lower than with single agents. A higher tumor K-ras mutation rate was observed with L2G7 alone compared to controls, suggesting that agents targeting HGF may be less effective against mutated K-ras lung tumors. This was not observed with combination treatment. A small molecule c-Met inhibitor decreased formation of both K-ras wild-type and mutant tumors and showed additive anti-tumor effects when combined with gefitinib. Dual targeting of c-Met/EGFR may have clinical benefit for lung cancer.

Phase II Study of Docetaxel and Gefitinib as Second-Line Therapy in Gemcitabine Pretreated Patients with Advanced Pancreatic Cancer

Background: There is no standard second-line therapy for advanced pancreatic cancer (APC). We evaluated the epidermal growth factor receptor (EGFR) inhibitor gefitinib and docetaxel in a phase II study following gemcitabine failure. Methods: EGFR overexpression was not required. The initial docetaxel dose was 75 mg/m2 on day 1 every 21 days. Due to febrile neutropenia in 8 of the first 18 patients, the dose was reduced to 60 mg/m2. Gefitinib, 250 mg/day orally, was given continuously. Results: Forty-one patients received treatment and were evaluable. Febrile neutropenia was seen in 11 patients (27%), with most events occurring at the docetaxel dose of 75 mg/m2 (8 of 18 patients). Common treatment-related grade 3/4 toxicities were: fatigue (7%), nausea (7%), diarrhea (5%) and vomiting (2%). There was 1 partial response and stable disease in 19 patients. Time to progression was 1.8 months and median survival was 4.5 months (95% CI 2.9–5.7). Conclusion: The tolerability and feasibility of second-line therapy for APC was demonstrated. The combination of gefitinib and docetaxel showed evidence of limited efficacy.

Deletion of the RNA-Editing Enzyme ADAR1 Causes Regression of Established Chronic Myelogenous Leukemia in Mice

Patients with chronic myelogenous leukemia (CML) respond well to tyrosine kinase inhibitors (TKIs) of the Bcr‐Abl oncoprotein. However, intolerance and resistance to these agents remains a challenge, and TKIs are unable to eradicate rare leukemia‐initiating cells. Leukemia treatment would benefit from a better understanding of molecular signals that are necessary for the survival of leukemia‐initiating cells but dispensable for normal hematopoietic stem cells. Leukemia‐initiating cells in CML can arise from myeloid progenitor cells, a population that we have reported in normal hematopoiesis to depend on the RNA‐editing enzyme adenosine deaminase acting on RNA‐1 (ADAR1). We now report that Bcr‐Abl transformed leukemic cells were ADAR1‐dependent in a conditional ADAR1 knockout mouse model. ADAR1 deletion reversed leukocytosis and splenomegaly, and preferentially depleted primitive Lin‐Sca+Kit+ (LSK) leukemic cells but not LSK cells lacking the leukemic oncoprotein. ADAR1 deletion ultimately normalized the peripheral white blood count, eliminating leukemic cells as assessed by PCR. These results uncover a novel requirement for ADAR1 in myeloid leukemic cells and indicate that ADAR1 may comprise a new molecular target for CML‐directed therapeutics.

PROGNOSTIC FACTORS IN PATIENTS WITH HIGH-RISK LOCALLY ADVANCED SALIVARY GLAND CANCERS TREATED WITH SURGERY AND POSTOPERATIVE RADIOTHERAPY

This study was designed to identify the factors associated with the outcome after standard treatment with surgery and postoperative radiotherapy (RT) for locally advanced salivary gland cancers.

Longitudinal evaluation of cancer-associated biomarkers before and after weight loss in RENEW study participants: Implications for cancer risk reduction

INTRODUCTION Obesity is a major risk factor for the development of endometrial cancer (EC). An improved understanding of biologic mechanisms associated with weight loss, including alteration in inflammation, hormonal balance, and cancer antigens expression may lead to the development of effective cancer prevention strategies. The goal of this study was to explore longitudinal biomarker changes in obese women who underwent weight loss intervention, testing the hypothesis biomarker levels can be altered through intentional weight loss. METHODS Serum samples from 89 participants with Class II and Class III obesity and 43 non morbidly obese comparisons were obtained in Re-Energize with Nutrition, Exercise and Weight Loss (RENEW) study as previously reported. Twenty-one bead-based xMAP immunoassays were utilized, including cancer-associated antigens, cytokines, chemokines, and hormones. One-way repeated measures ANOVA was used to examine the association between changes in biomarker expression levels over time (baseline, 6 months and 12 months). Linear mixed effects models were used to examine longitudinal relationships between biomarker expression levels. RESULTS Mean levels of VEGF, soluble E-selectin, GH, adiponectin, IL-6, IL-7, CA-125, and IGFBP-1 significantly differed between time periods. In adjusted mixed linear models, decreasing BMI was significantly associated with lower levels of soluble E-selectin and IL-6 and increases in GH, adiponectin, and IGFBP-1. CONCLUSIONS This is one of the first efforts to explore changes in cancer-associated biomarkers in a cohort of weight loss research participants at high risk for EC development. Our findings demonstrate that changes in the expression of markers can be achieved with weight loss intervention.