Citations

Abstract Introduction: CD56+ lymphocytes (a defining marker of natural killer cells) have a predominantly cytotoxic phenotype and a hypothetical role in breast tumor immunosurveillance. Here we investigate whether CD56+ staining density varies in nonmalignant breast lobules according to confirmed breast cancer risk factors- age, and histologic features of fibrocystic change and lobular involution. Methods: Archived breast tissue samples were obtained from 94 women with benign breast disease (BBD). The sample set was selected as a nested case-control study (47 cases, 47 controls) from within a large BBD cohort; cases were those who developed breast cancer subsequent to their benign breast biopsy; controls were matched to cases on age at biopsy, year of biopsy, and length of breast cancer free follow-up at least as long as the time-to-cancer in the matched case. Up to 10 representative lobules in each sample were characterized by H&E for fibrocystic changes and the degree of epithelial proliferation (normal, nonproliferative, proliferative, atypia) and for degree of lobular involution (none, partial, complete). Consecutive sections were immunostained for CD56 and hematoxylin. Using digital image analysis, CD56 staining was quantified on a per lobule basis by pixel ratio (PR) (positive stain:total lobule). Statistical analysis was performed using linear mixed effects regression on the rank transformed density to account for correlations among multiple lobules from the same patient in assessing the association of density with lobule characteristics and using conditional logistic regression for association with case-control status. Results: Among 94 women (median age 52, range 35-73), 876 lobules were evaluated: 431 in BBD cases and 445 in BBD controls. Overall, 391 lobules (45%) were normal and the remaining 485 (55%) demonstrated fibrocystic changes. Among fibrocystic lobules, 247 (51%) had nonproliferative changes, 218 (45%) had epithelial proliferation, and 20 (4%) had atypical hyperplasia. Among normal lobules, 61 (16%) had no involution, 139 (36%) had partial involution, and 191 (49%) had complete involution. The vast majority of lobules (861/876, 98%) demonstrated presence of CD56+ cells, while only 15 of 876 lobules in 11 patients had zero CD56+ cells [7 cases (15%) versus 4 controls (8.5%) OR 1.75, p = 0.37]. The median CD56+ PR was 0.55% overall. Fibrocystic lobules as a group showed significantly lower median CD56+ PR compared to normal lobules (0.37% vs 0.85%, p < 0.0001). Among subcategories of fibrocystic lobules, the median CD56+ PR was lower in proliferative lobules (0.29%) compared to non-proliferative (0.42%), but this difference was not statistically significant (p = 0.55). Older women (age > 55) showed the highest CD56+ PR (median of 0.92%), as compared to 0.38% in women 45-55 (p=0.02), and 0.52% in women age <45 (p = 0.26). Among normal lobules, median CD56+ PR was similar between lobules with no involution (0.55%) and partial involution (0.52%) but was considerably higher among lobules with complete involution (1.3%, p = 0.09 and p = 0.05, respectively). In a multivariable model, CD56+ PR differences between fibrocystic and normal lobules remained significant (p = 0.0002) and also remained significant between age groups of > 55 and 45-55 (p = 0.02), while involution was non-significant. Median CD56+ PR was lower in cases (0.43%) compared to controls (0.72%), but this was not statistically significant (p=0.19) in our sample of 47 case-control pairs. Conclusions: Breast lobules with fibrocystic changes show less CD56+ cells, raising a question of possible immune suppression induced by early epithelial abnormalities. These findings encourage further investigation to improve understanding of the immune microenvironment in premalignant breast tissues. Citation Format: Rushin D. Brahmbhatt, Daniel Kerekes, Tanya L. Hoskin, Alvaro Pena, Daniel W. Visscher, Melody L. Stallings-Mann, Derek C. Radisky, Linda M. Murphy, Vernon Shane Pankratz, Keith L. Knutson, Marlene Frost, Amy C. Degnim. CD56+ immune cell infiltration is decreased in benign breast lobules with fibrocystic changes. [abstract]. In: Proceedings of the Thirteenth Annual AACR International Conference on Frontiers in Cancer Prevention Research; 2014 Sep 27-Oct 1; New Orleans, LA. Philadelphia (PA): AACR; Can Prev Res 2015;8(10 Suppl): Abstract nr B34.

Abstract Introduction: Estrogen receptor beta (ERβ), which is highly expressed in benign breast epithelium, is postulated to function as a tumor suppressor of breast cancer. Atypias of the breast increase the lifetime risk of breast cancer four-fold. However, little is known about ERβ expression in association with atypias or whether ERβ plays a role in mitigating breast cancer risk in high-risk individuals. We therefore undertook this study to examine the relationship of ERβ expression in atypias and adjacent normal lobules with the risk of subsequent breast cancer. Methods: We studied women in a well-characterized benign breast disease cohort with atypical ductal hyperplasia (ADH) or atypical lobular hyperplasia (ALH) diagnosed from 1967 to 1991. Nuclear and cytoplasmic ERβ expression was assessed via immunohistochemistry in both the atypical hyperplasia epithelium (atypia) and background normal lobules for percent (scores 0-4 for <1%, 1-25%, 26-50%, 51-75%, >75%, respectively) and intensity (scores 0-3 for negative, weak, intermediate, strong, respectively) using a highly specific ERβ monoclonal antibody (PPG5/10). For nuclear staining, an ERβ sum score (percent + intensity, range 0-7) was created and grouped as low (0-2), moderate (3-5) or high (6-7). Competing risks regression was used to assess the association of ERβ expression with future breast cancer risk while also accounting for the competing risk of death from other causes. Results: 171 women, median age 56, were studied (79 ADH and 92 ALH). Median follow-up was 15 years overall, and 36 women developed breast cancer at a median of 13 years after their atypia biopsy. ERβ expression was lower in the atypia versus normal lobules whether evaluated by nuclear percent stained, nuclear intensity or cytoplasmic intensity (all p < 0.001). For nuclear staining specifically, ERβ expression in the atypia was low in 44 (26%), moderate in 117 (68%) and high in only 10 (6%) based on the sum score. In contrast, ERβ was higher in the normal lobules with a majority showing high expression (n = 96, 56%), moderate expression in 74 (43%) and low expression in only 1 (0.6%). Lower ERβ nuclear expression in the atypia was associated with increased breast cancer risk, whether evaluated by percent staining, intensity or sum score; the same was true for ERβ nuclear expression in the background normal lobules. Low ERβ expression in the atypia (sum score 0-2) was associated with a 2-fold increased risk of subsequent breast cancer compared to atypia with moderate-high expression (sum score 3-7), HR 2.0, 95% CI: 1.02-3.8, p = 0.04. Lower ERβ expression in the normal lobules was also associated with an increased risk of future breast cancer: HR = 2.5 (95% CI: 1.3-5.1, p = 0.009) for low-moderate versus high expression. Conclusions: Increased ERβ expression in normal and atypical lobules was associated with a significantly decreased risk of breast cancer in our high-risk patient cohort. These data suggest that in women with atypical hyperplasia, ERβ expression is protective against the future development of breast cancer. ERβ may serve as a useful biomarker to further stratify breast cancer risk in women with benign breast disease. Citation Format: Tina J. Hieken, Jodi M. Carter, John R. Hawse, IV, Tanya L. Hoskin, Marlene Frost, Lynn C. Hartmann, Derek C. Radisky, Daniel W. Visscher, Vernon S. Pankratz, Amy C. Degnim. ERβ expression and breast cancer risk prediction for women with atypias. [abstract]. In: Proceedings of the Thirteenth Annual AACR International Conference on Frontiers in Cancer Prevention Research; 2014 Sep 27-Oct 1; New Orleans, LA. Philadelphia (PA): AACR; Can Prev Res 2015;8(10 Suppl): Abstract nr A03.

Hidradenocarcinoma is a rare aggressive form of cutaneous adnexal skin carcinoma originating from the sweat gland. Due to its low incidence, prognostic and treatment strategies are still being explored both for primary and advanced disease. This tumor most often presents as either solid or cystic appearing subcutaneous nodules, which may be associated with pruritus or ulceration. To date the mainstay of treatment for local disease has been surgical excision; however, the paucity of historical data available has shown that these tumors often behave aggressively with high rates of local recurrence, metastasis, and poor overall outcomes. There are few case reports describing the utility of radiation therapy in the treatment of hidradenocarcinoma. Herein, we present a case of metastatic apocrine hidradenocarcinoma in a 32-year-old Caucasian male. The patient initially underwent excisional biopsy which confirmed the diagnosis of poorly differentiated, highly infiltrative, apocrine hidradenocarcinoma. He received systemic chemotherapy for metastatic disease, followed by radiation therapy to areas of grossly palpable adenopathy. Prior to radiation therapy the patient had an enlarged hypermetabolic conglomerate of lymph nodes in the right axilla, and borderline enlarged low activity nodes within the left axilla. He received 3 cycles of chemotherapy followed by tamoxifen and radiation therapy (50.4 Gy in 28 fractions) to areas of progressive disease in the bilateral axilla, lower neck, and axillary skin. Following treatment, the patient had complete resolution of skin nodules and improvement of his pruritus. While the role of radiation therapy in the treatment of hidradenocarcinoma has not been well established, this case report demonstrated the potential benefit of external beam radiotherapy in the management of this rare disease.

Abstract Clinical trials have established the benefit of androgen deprivation therapy (ADT) combined with radiotherapy in prostate cancer. ADT sensitizes prostate cancer to radiotherapy-induced death at least in part through inhibition of DNA repair machinery, but for unknown reasons, adjuvant ADT provides further survival benefits. Here, we show that androgen receptor (AR) expression and activity are durably upregulated following radiotherapy in multiple human prostate cancer models in vitro and in vivo. Moreover, the degree of AR upregulation correlates with survival in vitro and time to tumor progression in animal models. We also provide evidence of AR pathway upregulation, measured by a rise in serum levels of AR-regulated hK2 protein, in nearly 20% of patients after radiotherapy. Furthermore, these men were three-fold more likely to experience subsequent biochemical failure. Collectively, these data demonstrate that radiotherapy can upregulate AR signaling after therapy to an extent that negatively affects disease progression and/or survival. Cancer Res; 75(22); 4688–96. ©2015 AACR.

Celiac disease (CD) is an inflammatory disorder triggered by ingested gluten, causing immune-mediated damage to the small-intestinal mucosa. Gluten proteins are strikingly similar in amino acid composition and sequence to proline-rich proteins (PRPs) in human saliva. On the basis of this feature and their shared destination in the gastrointestinal tract, we hypothesized that salivary PRPs may modulate gluten-mediated immune responses in CD. Parotid salivary secretions were collected from CD patients, refractory CD patients, non-CD patients with functional gastrointestinal complaints, and healthy controls. Structural similarities of PRPs with gluten were probed with anti-gliadin antibodies. Immune responses to PRPs were investigated toward CD patient-derived peripheral blood mononuclear cells and in a humanized transgenic HLA-DQ2/DQ8 mouse model for CD. Anti-gliadin antibodies weakly cross-reacted with the abundant salivary amylase but not with PRPs. Likewise, the R5 antibody, recognizing potential antigenic gluten epitopes, showed negligible reactivity to salivary proteins from all groups. Inflammatory responses in peripheral blood mononuclear cells were provoked by gliadins whereas responses to PRPs were similar to control levels, and PRPs did not compete with gliadins in immune stimulation. In vivo, PRP peptides were well tolerated and nonimmunogenic in the transgenic HLA-DQ2/DQ8 mouse model. Collectively, although structurally similar to dietary gluten, salivary PRPs were nonimmunogenic in CD patients and in a transgenic HLA-DQ2/DQ8 mouse model for CD. It is possible that salivary PRPs play a role in tolerance induction to gluten early in life. Deciphering the structural basis for the lack of immunogenicity of salivary PRPs may further our understanding of the toxicity of gluten.

ABSTRACT Although the role of ERα in regulating bone metabolism has been extensively studied, ERβ has been largely dismissed as a relevant modulator of bone mass. Previous studies examining ERβ utilized a germline knockout mouse expressing transcript variants of ERβ and displaying systemic hormonal changes that confounded interpretation of the skeletal phenotype. Thus, we used a conditional ERβ mouse model to achieve deletion of ERβ specifically in early osteoprogenitor cells using the Prx1-Cre driver. We observed marked increases in the trabecular bone volume fraction (of 58% [p < 0.003] and 93% [p < 0.0003] in 6- and 12-week-old female ERβPrx1–CKO mice, respectively) but no changes in cortical bone. Serum estradiol and IGF-I levels were unaltered in ERβPrx1–CKO mice. Bone formation and resorption indices by histomorphometry and serum assays were unchanged in these mice, suggesting that alterations in bone turnover may have occurred early in development. However, the ratio of colony-forming unit-osteoblasts (CFU-OBs) to CFU-fibroblasts (CFU-Fs) was increased in bone marrow cultures from ERβPrx1–CKO compared with control mice, indicating increased differentiation of osteoblast precursor cells into osteoblasts in ERβPrx1–CKO mice. Detailed quantitative polymerase chain reaction analyses of 128 genes in 16 prespecified pathways revealed significant downregulation of 11 pathways in ERβPrx1–CKO mice. Thus, deletion of ERβ specifically in osteoblast lineage cells, in the absence of all splice variants, increases trabecular bone mass and modulates multiple pathways related to bone metabolism. These findings suggest that pharmacological inhibition of ERβ in bone may provide a novel approach to treat osteoporosis. © 2015 American Society for Bone and Mineral Research.

Abstract Pancreatic ductal adenocarcinoma (PDAC) offers an optimal model for discovering “druggable” molecular pathways that participate in inflammation-associated cancer development. Chronic pancreatitis, a common prolonged inflammatory disease, behaves as a well-known premalignant condition that contributes to PDAC development. Although the mechanisms underlying the pancreatitis-to-cancer transition remain to be fully elucidated, emerging evidence supports the hypothesis that the actions of proinflammatory mediators on cells harboring Kras mutations promote neoplastic transformation. Recent elegant studies demonstrated that the IL17 pathway mediates this phenomenon and can be targeted with antibodies, but the downstream mechanisms by which IL17 functions during this transition are currently unclear. In this study, we demonstrate that IL17 induces the expression of REG3β, a well-known mediator of pancreatitis, during acinar-to-ductal metaplasia and in early pancreatic intraepithelial neoplasia (PanIN) lesions. Furthermore, we found that REG3β promotes cell growth and decreases sensitivity to cell death through activation of the gp130-JAK2-STAT3-dependent pathway. Genetic inactivation of REG3β in the context of oncogenic Kras-driven PDAC resulted in reduced PanIN formation, an effect that could be rescued by administration of exogenous REG3β. Taken together, our findings provide mechanistic insight into the pathways underlying inflammation-associated pancreatic cancer, revealing a dual and contextual pathophysiologic role for REG3β during pancreatitis and PDAC initiation. Cancer Res; 75(22); 4852–62. ©2015 AACR.

ABSTRACTEpithelial‐mesenchymal transition (EMT) is a process whereby epithelial cells assume mesenchymal characteristics to facilitate cancer metastasis. However, EMT also contributes to the initiation and development of primary tumors. Prior studies that explored the hypothesis that EMT gene variants contribute to epithelial ovarian carcinoma (EOC) risk have been based on small sample sizes and none have sought replication in an independent population. We screened 15,816 single‐nucleotide polymorphisms (SNPs) in 296 genes in a discovery phase using data from a genome‐wide association study of EOC among women of European ancestry (1,947 cases and 2,009 controls) and identified 793 variants in 278 EMT‐related genes that were nominally (P < 0.05) associated with invasive EOC. These SNPs were then genotyped in a larger study of 14,525 invasive‐cancer patients and 23,447 controls. A P‐value <0.05 and a false discovery rate (FDR) <0.2 were considered statistically significant. In the larger dataset, GPC6/GPC5 rs17702471 was associated with the endometrioid subtype among Caucasians (odds ratio (OR) = 1.16, 95% CI = 1.07–1.25, P = 0.0003, FDR = 0.19), whereas F8 rs7053448 (OR = 1.69, 95% CI = 1.27–2.24, P = 0.0003, FDR = 0.12), F8 rs7058826 (OR = 1.69, 95% CI = 1.27–2.24, P = 0.0003, FDR = 0.12), and CAPN13 rs1983383 (OR = 0.79, 95% CI = 0.69–0.90, P = 0.0005, FDR = 0.12) were associated with combined invasive EOC among Asians. In silico functional analyses revealed that GPC6/GPC5 rs17702471 coincided with DNA regulatory elements. These results suggest that EMT gene variants do not appear to play a significant role in the susceptibility to EOC.