Sharon B. Sams

Targeted inhibition of Src kinase with dasatinib blocks thyroid cancer growth and metastasis

Purpose: There are no effective therapies for patients with poorly differentiated papillary thyroid cancer (PTC) or anaplastic thyroid cancer (ATC), and metastasis to the bone represents a significantly worse prognosis. Src family kinases (SFKs) are overexpressed and activated in numerous tumor types and have emerged as a promising therapeutic target, especially in relation to metastasis. We recently showed that Src is overexpressed and activated in thyroid cancer. We therefore tested whether inhibition of Src with dasatinib (BMS-354825) blocks thyroid cancer growth and metastasis. Experimental Design: The effects of dasatinib on thyroid cancer growth, signaling, cell cycle, and apoptosis were evaluated in vitro. The therapeutic efficacy of dasatinib was further tested in vivo using an orthotopic and a novel experimental metastasis model. Expression and activation of SFKs in thyroid cancer cells was characterized, and selectivity of dasatinib was determined using an Src gatekeeper mutant. Results: Dasatinib treatment inhibited Src signaling, decreased growth, and induced cell-cycle arrest and apoptosis in a subset of thyroid cancer cells. Immunoblotting showed that c-Src and Lyn are expressed in thyroid cancer cells and that c-Src is the predominant SFK activated. Treatment with dasatinib blocked PTC tumor growth in an orthotopic model by more than 90% (P = 0.0014). Adjuvant and posttreatment approaches with dasatinib significantly inhibited metastasis (P = 0.016 and P = 0.004, respectively). Conclusion: These data provide the first evidence that Src is a central mediator of thyroid cancer growth and metastasis, indicating that Src inhibitors may have a higher therapeutic efficacy in thyroid cancer, as both antitumor and antimetastatic agents. Clin Cancer Res; 18(13); 3580–91. ©2012 AACR.

The Clinical Impact of Immediate On-Site Cytopathology Evaluation During Endoscopic Ultrasound-Guided Fine Needle Aspiration of Pancreatic Masses: A Prospective Multicenter Randomized Controlled Trial

Objectives:Observational data on the impact of on-site cytopathology evaluation (OCE) during endoscopic ultrasonography-guided fine needle aspiration (EUS–FNA) of pancreatic masses have reported conflicting results. We aimed to compare the diagnostic yield of malignancy and proportion of inadequate specimens between patients undergoing EUS–FNA of pancreatic masses with and without OCE.Methods:In this multicenter randomized controlled trial, consecutive patients with solid pancreatic mass underwent randomization for EUS–FNA with or without OCE. The number of FNA passes in the OCE+ arm was dictated by the on-site cytopathologist, whereas seven passes were performed in OCE− arm. EUS–FNA protocol was standardized, and slides were reviewed by cytopathologists using standardized criteria for cytologic characteristics and diagnosis.Results:A total of 241 patients (121 OCE+, 120 OCE−) were included. There was no difference between the two groups in diagnostic yield of malignancy (OCE+ 75.2% vs. OCE− 71.6%, P=0.45) and proportion of inadequate specimens (9.8 vs. 13.3%, P=0.31). Procedures in OCE+ group required fewer EUS–FNA passes (median, OCE+ 4 vs. OCE− 7, P<0.0001). There was no significant difference between the two groups with regard to overall procedure time, adverse events, number of repeat procedures, costs (based on baseline cost-minimization analysis), and accuracy (using predefined criteria for final diagnosis of malignancy). There was no difference between the two groups with respect to cytologic characteristics of cellularity, bloodiness, number of cells/slide, and contamination.Conclusions:Results of this study demonstrated no significant difference in the diagnostic yield of malignancy, proportion of inadequate specimens, and accuracy in patients with pancreatic mass undergoing EUS–FNA with or without OCE.

Thioredoxin interacting protein (TXNIP) is a novel tumor suppressor in thyroid cancer

BackgroundThyroid cancer is the most common endocrine malignancy, and many patients with metastatic differentiated thyroid cancer (DTC), poorly differentiated thyroid cancer (PDTC), and anaplastic thyroid cancer (ATC) fail to respond to conventional therapies, resulting in morbidity and mortality. Additional therapeutic targets and treatment options are needed for these patients. We recently reported that peroxisome proliferator-activated receptor gamma (PPARγ) is highly expressed in ATC and confers an aggressive phenotype when overexpressed in DTC cells.MethodsMicroarray analysis was used to identify downstream targets of PPARγ in ATC cells. Western blot analysis and immunohistochemistry (IHC) were used to assess thioredoxin interacting protein (TXNIP) expression in thyroid cancer cell lines and primary tumor specimens. Retroviral transduction was used to generate ATC cell lines that overexpress TXNIP, and assays that assess glucose uptake, viable cell proliferation, and invasion were used to characterize the in vitro properties of these cells. An orthotopic thyroid cancer mouse model was used to assess the effect of TXNIP overexpression in ATC cell lines in vivo.ResultsUsing microarray analysis, we show that TXNIP is highly upregulated when PPARγ is depleted from ATC cells. Using Western blot analysis and IHC, we show that DTC and ATC cells exhibit differential TXNIP expression patterns. DTC cell lines and patient tumors have high TXNIP expression in contrast to low or absent expression in ATC cell lines and tumors. Overexpression of TXNIP decreases the growth of HTh74 cells compared to vector controls and inhibits glucose uptake in the ATC cell lines HTh74 and T238. Importantly, TXNIP overexpression in T238 cells results in attenuated tumor growth and decreased metastasis in an orthotopic thyroid cancer mouse model.ConclusionsOur findings indicate that TXNIP functions as a tumor suppressor in thyroid cells, and its downregulation is likely important in the transition from differentiated to advanced thyroid cancer. These studies underscore the potential of TXNIP as a novel therapeutic target and prognostic indicator in advanced thyroid cancer.

PD-1+Tim-3+ CD8+ T Lymphocytes Display Varied Degrees of Functional Exhaustion in Patients with Regionally Metastatic Differentiated Thyroid Cancer

Severson and colleagues show that exhaustion of PD-1+ T cells in tumor-involved lymph nodes from patients with metastatic differentiated thyroid cancer was not complete. While PD-1+CD8+ T cells were variably dysfunctional in their ability to produce cytokines, their proliferative capacity was maintained, and PD-1+CD4+ T cells remained functional. Regional metastatic differentiated thyroid cancer (mDTC) provides a unique model in which to study the tumor–immune interface. These lymph node metastases persist for years, generally without progression to distant metastases. Although the immune system likely impedes disease progression, it is unsuccessful in eliminating disease. Our previous studies revealed that programmed death-1 (PD-1)+ T cells were enriched in tumor-involved lymph nodes (TILN). Tumor-associated leukocytes and tumor cells were collected from grossly involved lymph nodes from 12 patients to further characterize the phenotype and functional potential of mDTC-associated PD-1+ T cells. PD-1+CD4+ and PD-1+CD8+ T cells were enriched in 8 of 12 TILN samples. PD-1+ T cells coexpressed Tim-3 and CD69 and failed to downregulate CD27. CD8+ T cells, but not CD4+ T cells, from these samples were variably deficient in their ability to produce effector cytokines when compared with control TILNs that lacked resident PD-1+ T cells. PD-1+CD8+ T cells were capable of exocytosis but lacked intracellular perforin. Surprisingly, T-cell proliferative capacity was largely maintained in all samples. Thus, although PD-1 expression by mDTC-associated CD8+ T cells was associated with dysfunction, exhaustion was not complete. Notably, molecular markers of exhaustion did not translate to dysfunction in all samples or in CD4+ T cells. Regulatory T cells (Treg), PD-L1, and galectin-9 were commonly found in mDTC and likely contributed to the initiation of T-cell exhaustion and disease progression. Therapies that release the effects of PD-1 and Tim-3 and reduce the suppressive effects of Tregs may encourage tumor elimination in patients with mDTC. Cancer Immunol Res; 3(6); 620–30. ©2015 AACR.

Tumor-Infiltrating T Cells and the PD-1 Checkpoint Pathway in Advanced Differentiated and Anaplastic Thyroid Cancer

CONTEXT Five to 10% of patients with differentiated thyroid cancers (DTC) develop invasive and/or distant metastatic disease that is marginally improved with standard therapies. Prognosis is poor for patients with anaplastic thyroid cancer, with a median survival of 3-5 months. We suggest that a paradigm shift is necessary in the treatment of advanced cases. OBJECTIVE We hypothesized that a T-cell response is generated in advanced thyroid cancer and may be a viable therapeutic target. DESIGN Primary DTCs were analyzed by quantitative RT-PCR (n = 92) for expression of CD3, CD8, forkhead box (Fox)-P3, programmed death (PD)-1, PD-1 ligand-1, and PD-1 ligand-2 and biopsied for cellular analysis by flow cytometry (n = 11). Advanced pT4 cases (n = 22) and metastases (n = 5) were analyzed by immunohistochemistry. SETTING The study was conducted at the University of Colorado Hospital. PATIENTS Thyroid cancer patients undergoing thyroidectomy or completion surgery for advanced disease between 2002 and 2013 participated in the study. INTERVENTION There were no interventions. MAIN OUTCOME MEASURE Immune markers were analyzed for association with disease severity. RESULTS Immune markers were commonly expressed at the RNA level. PD-L1 was higher (P = .0443) in patients with nodal metastases. FoxP3(+) (P < .0001), PD-1(+)CD8(+) (P = .0058), and PD-1(+)CD4(+) (P = .0104) T cells were enriched in DTC biopsies. CD8(+) and FoxP3(+) T cells were detected by immunohistochemistry in all pT4 tumors and a subset of metastases. PD-1(+) lymphocytes were found in 50% of DTCs. PD-L1 was expressed by tumor and associated leukocytes in 13 of 22 cases, and expression was more diffuse in anaplastic thyroid cancer (P = .0373). BRAF(V600E) mutation was associated with higher frequencies of tumor-associated lymphocytes (P = .0095) but not PD-L1 expression. CONCLUSIONS PD-1 checkpoint blockades may have therapeutic efficacy in patients with aggressive forms of thyroid cancer.

Liquid-Based Papanicolaou Tests in Endometrial Carcinoma Diagnosis Performance, Error Root Cause Analysis, and Quality Improvement

Recent reports show that the sensitivity of endometrial carcinoma detection on liquid-based Papanicolaou (Pap) tests (88%) is considerably higher than that reported on conventional Pap smears (20%-30%), although few laboratories have corroborated these results. We performed a 5-year retrospective review of all liquid-based Pap tests (n = 69) in women who later were given a diagnosis of endometrial carcinoma, performed error root cause analysis, and developed quality improvement initiatives as a means of error reduction. The original and rescreened Pap test sensitivity rates for endometrial carcinoma were 31.9% and 59.3%, respectively. Root cause analysis showed that poor specimen quality and cognitive failures contributed to a false-negative error in 67% (18/27) and 59% (16/27), respectively, of all cases. System analysis showed that latent factors contributing to error included lack of redundant and educational systems. We conclude that system redesign of liquid-based Pap test screening processes has the potential to improve sensitivity in endometrial carcinoma diagnosis.

Increasing Number of Passes Beyond 4 Does Not Increase Sensitivity of Detection of Pancreatic Malignancy by Endoscopic Ultrasound–Guided Fine-Needle Aspiration

BACKGROUND & AIMS It is not clear exactly how many passes are required to determine whether pancreatic masses are malignant using endoscopic ultrasound–guided fine‐needle aspiration (EUS‐FNA). We aimed to define the per‐pass diagnostic yield of EUS‐FNA for establishing the malignancy of a pancreatic mass, and identify factors associated with detection of malignancies. METHODS In a prospective study, 239 patients with solid pancreatic masses were randomly assigned to groups that underwent EUS‐FNA, with the number of passes determined by an on‐site cytopathology evaluation or set at 7 passes, at 3 tertiary referral centers. A final diagnosis of pancreatic malignancy was made based on findings from cytology, surgery, or a follow‐up evaluation at least 1 year after EUS‐FNA. The cumulative sensitivity of detection of malignancy by EUS‐FNA was calculated after each pass; in the primary analysis, lesions categorized as malignant or suspicious were considered as positive findings. RESULTS Pancreatic malignancies were found in 202 patients (84.5% of the study population). EUS‐FNA detected malignancies with 96% sensitivity (95% confidence interval [CI], 92%–98%); 4 passes of EUS‐FNA detected malignancies with 92% sensitivity (95% CI, 87%–95%). Tumor size greater than 2 cm was the only variable associated with positive results from cytology analysis (odds ratio, 7.8; 95% CI, 1.9–31.6). In masses larger than 2 cm, 4 passes of EUS‐FNA detected malignancies with 93% sensitivity (95% CI, 89%–96%) and in masses ≤2 cm, 6 passes was associated with 82% sensitivity (95% CI, 61%–93%). Sensitivity of detection did not increase with increasing number of passes. CONCLUSIONS In a prospective study, we found 4 passes of EUS‐FNA to be sufficient to detect malignant pancreatic masses; increasing the number of passes did not increase the sensitivity of detection. Tumor size greater than 2 cm was associated with malignancy, and a greater number of passes may be required to evaluate masses 2 cm or less. ClinicalTrials.gov number, NCT01386931.

Fibroblast Subtypes Regulate Responsiveness of Luminal Breast Cancer to Estrogen

Purpose: Antiendocrine therapy remains the most effective treatment for estrogen receptor–positive (ER+) breast cancer, but development of resistance is a major clinical complication. Effective targeting of mechanisms that control the loss of ER dependency in breast cancer remains elusive. We analyzed breast cancer–associated fibroblasts (CAF), the largest component of the tumor microenvironment, as a factor contributing to ER expression levels and antiendocrine resistance. Experimental Design: Tissues from patients with ER+ breast cancer were analyzed for the presence of CD146-positive (CD146pos) and CD146-negative (CD146neg) fibroblasts. ER-dependent proliferation and tamoxifen sensitivity were evaluated in ER+ tumor cells cocultured with CD146pos or CD146neg fibroblasts. RNA sequencing was used to develop a high-confidence gene signature that predicts for disease recurrence in tamoxifen-treated patients with ER+ breast cancer. Results: We demonstrate that ER+ breast cancers contain two CAF subtypes defined by CD146 expression. CD146neg CAFs suppress ER expression in ER+ breast cancer cells, decrease tumor cell sensitivity to estrogen, and increase tumor cell resistance to tamoxifen therapy. Conversely, the presence of CD146pos CAFs maintains ER expression in ER+ breast cancer cells and sustains estrogen-dependent proliferation and sensitivity to tamoxifen. Conditioned media from CD146pos CAFs with tamoxifen-resistant breast cancer cells are sufficient to restore tamoxifen sensitivity. Gene expression profiles of patient breast tumors with predominantly CD146neg CAFs correlate with inferior clinical response to tamoxifen and worse patient outcomes. Conclusions: Our data suggest that CAF composition contributes to treatment response and patient outcomes in ER+ breast cancer and should be considered a target for drug development. Clin Cancer Res; 23(7); 1710–21. ©2016 AACR.

Diagnosis of ectopic pancreas by endoscopic ultrasound with fine-needle aspiration

AIM To study the clinical, endoscopic, sonographic, and cytologic features of ectopic pancreas (EP). METHODS This was a retrospective study performed at an academic referral center including two hospitals. Institutional review board approval was obtained. Patients referred to the University Hospital or Denver Health Medical Center Gastrointestinal Endoscopy Lab for gastroduodenal subepithelial lesions (SEL) with a final diagnosis of EP between January 2009 and December 2013 were identified. Patients in this group were selected for the study if they underwent endoscopic ultrasound (EUS) with fine-needle aspiration (FNA) or deep biopsy. A review of the medical record was performed specifically to review the following information: presenting symptoms, endoscopic and EUS findings, computed tomography or magnetic resonance imaging findings, pathology results, procedure-related adverse events, and subsequent treatments after EUS-FNA. EUS with FNA or deep submucosal biopsy was performed in all patients on an outpatient basais by one of two physicians (Attwell A, Fukami N). Review of all subsequent clinic notes and operative reports was performed in order to determine follow-up and final diagnoses. RESULTS Between July 2009 and December 2013, 10 patients [3 males, 7 females, median age 52 (26-64) years] underwent EUS for a gastroduodenal SEL and were diagnosed with EP. One patient was symptomatic. Six (60%) lesions were in the antrum, 3 (30%) in the body, and 1 (10%) in the duodenum. A mucosal dimple was noted in 6 (60%). Mean lesion size was 17 (8-25) mm. Gastrointestinal wall involvement: muscularis mucosae, 10%; submucosa, 70%; muscularis propria, 60%; and serosa, 10%. Nine (90%) lesions were hypoechoic and 5 (50%) were homogenous. A duct was seen in 5 (50%). FNA was attempted in 9 (90%) and successful in 8 (80%) patients after 4 (2-6) passes. Cytology showed acini or ducts in 7 of 8 (88%). Superficial biopsies in 7 patients (70%) showed normal gastric mucosa. Deep endoscopic biopsies were taken in 2 patients and diagnostic in one. One patient (10%) developed pancreatitis after EUS-FNA. Two patients (20%) underwent surgery to relieve symptoms or confirm the diagnosis. The main limitation of the study was the fact that it was retrospective and performed at a single medical center. CONCLUSION EUS features of EP include antral location, mucosal dimple, location in layers 3-4, and lesional duct, and FNA or biopsy is accurate and effective.

Interobserver agreement among cytopathologists in the evaluation of pancreatic endoscopic ultrasound- guided fine needle aspiration cytology specimens *

Background and aims: Endoscopic ultrasound with fine needle aspiration (EUS-FNA) has become the standard of care in the evaluation of solid pancreatic lesions. Limited data exist on interobserver agreement (IOA) among cytopathologists in assessing solid pancreatic EUS-FNA specimens. This study aimed to evaluate IOA among cytopathologists in assessing EUS-FNA cytology specimens of solid pancreatic lesions using a novel standardized scoring system and to assess individual clinical and cytologic predictors of IOA. Methods: Consecutive patients who underwent EUS-FNA of solid pancreatic lesions at a tertiary care referral center were included. EUS-FNA slides were evaluated by four blinded cytopathologists using a standardized scoring system that assessed final cytologic diagnosis and quantitative (number of nucleated/diagnostic cells) and qualitative (bloodiness, inflammation/necrosis, contamination, artifact) cytologic parameters. Final clinical diagnosis was based on final cytology, surgical pathology, or 1-year clinical follow-up. IOA was calculated using multi-rater kappa (κ) statistics. Bivariate analyses were performed comparing cases with and without uniform agreement among the cytopathologists followed by logistic regression with backward elimination to model likelihood of uniform agreement. Results: Ninety-nine patients were included (49 % males, mean age 64 years, mean lesion size 26 mm). IOA for final diagnosis was moderate (κ = 0.45, 95 % confidence interval (CI) 0.4 – 0.49) with minimal improvement when combining suspicious and malignant diagnoses (κ = 0.54, 95 %CI 0.49 – 0.6). The weighted kappa value for overall diagnosis was 0.65 (95 %CI 0.54 – 0.76). IOA was slight to fair (κ = 0.04 – 0.32) for individual cytologic parameters. A final clinical diagnosis of malignancy was the most significant predictor of agreement [OR 3.99 (CI 1.52 – 10.49)]. Conclusions: Interobserver agreement among cytopathologists for pancreatic EUS-FNA specimens is moderate-substantial for the final cytologic diagnosis. The final clinical diagnosis of malignancy was the strongest predictor of agreement. These results have significant implications for patient management and need to be validated in future trials.