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INTRODUCTION The Louisiana Acadian region (population 1.2 million), home of the Cajuns, has among the highest US colorectal cancer (CRC) rates. Although Cajuns are a known genetic founder population, studies assessing for hereditary CRC have not been performed. METHODS A retrospective review of 2 hospital cancer registries was performed to identify young (

Supplemental digital content is available in the text., Objective Eighty percent of pancreatic ductal adenocarcinomas (PDAs) overexpress mucin 1 (MUC1), a transmembrane mucin glycoprotein. MUC1high PDA patients also express high levels of cyclooxygenase 2 (COX-2) and show poor prognosis. The cytoplasmic tail of MUC1 (MUC1-CT) partakes in oncogenic signaling, resulting in accelerated cancer progression. Our aim was to understand the regulation of Cox-2 expression by MUC1. Methods Levels of COX-2 and MUC1 were determined in MUC1−/−, MUC1low, and MUC1high PDA cells and tumors using reverse transcriptase–polymerase chain reaction, Western blot, and immunohistochemistry. Proliferative and invasive potential was assessed using MTT and Boyden chamber assays. Chromatin immunoprecipitation was performed to evaluate binding of MUC1-CT to the promoter of COX-2 gene. Results Significantly higher levels of COX-2 mRNA and protein were detected in MUC1high versus MUC1low/null cells, which were recapitulated in vivo. In addition, deletion of MUC1 gene and transient knockdown of MUC1 led to decreased COX-2 level. Also, MUC1-CT associated with the COX-2 promoter at ∼1000 base pairs upstream of the transcription start site, the same gene locus where nuclear factor κB p65 associates with the COX-2 promoter. Conclusions Data supports a novel regulation of COX-2 gene by MUC1 in PDA, the intervention of which may lead to a better therapeutic targeting in PDA patients.

Strongyloides stercoralis is a small intestinal nematode that is widespread in regions with poor sanitation. We present a 57-year-old man from Colombia who was undergoing corticosteroid therapy for a meningioma who presented after neurosurgery with abdominal pain and a profound gastrointestinal (GI) bleed. The patient underwent an esophagogastroduodenoscopy (EGD), an attempted embolization, and an exploratory laparotomy to remove the necrosed duodenum. His pathology examination revealed Strongyloides infection of the duodenum, and he died of profound blood loss. This rare diagnosis displays the importance of screening patients at a high risk of Strongyloides infection before starting glucocorticoid therapy.

We describe the advantages of a nulling coronagraph instrument behind a single aperture space telescope for detection and spectroscopy of Earth-like extrasolar planets in visible light. Our concept synthesizes a nulling interferometer by shearing the telescope pupil into multiple beams. They are recombined with a pseudo-achromatic pi-phase shift in one arm to produce a deep null on-axis, attenuating the starlight, while simultaneously transmitting the off-axis planet light. Our nulling configuration includes methods to mitigate stellar leakage, such as spatial filtering by a coherent array of single mode fibers, balancing amplitude and phase with a segmented deformable mirror, and post-starlight suppression wavefront sensing and control. With diffraction limited telescope optics and similar quality components in the optical train (λ/20), suppression of the starlight to 10-10 is readily achievable. We describe key features of the architecture and analysis, present the status of key experiments to demonstrate wide bandwidth null depth, and present the status of component technology development.

Direct detection of exo-planets from the ground will become a reality with the advent of a new class of extreme-adaptive optics instruments that will come on-line within the next few years. In particular, the Gemini Observatory will be developing the Gemini Planet Imager (GPI) that will be used to make direct observations of young exo-planets. One major technical challenge in reaching the requisite high contrast at small angles is the sensing and control of residual wave front errors after the starlight suppression system. This paper will discuss the nature of this problem, and our approach to the sensing and control task. We will describe a laboratory experiment whose purpose is to provide a means of validating our sensing techniques and control algorithms. The experimental demonstration of sensing and control will be described. Finally, we will comment on the applicability of this technique to other similar high-contrast instruments.

Introduction: Pancreatic Cancer (PC) is the fourth leading cause of cancer-related deaths in the United States. Over 80% of human pancreatic ductal adenocarcinomas (PDA) overexpress MUC1, a transmembrane mucin glycoprotein. MUC1high tumors are aggressive and patients with such tumors have poor prognosis. Interestingly, MUC1high PDA tumors overexpress cyclooxygenase-2 (COX-2), an inducible pro-inflammatory enzyme known to promote tumor progression and metastasis. Since the cytoplasmic domain of MUC1 (MUC1-C) is critically involved in the signal transduction cascade that promotes tumor progression and metastasis, we hypothesize that MUC1 induces its effect via regulating COX-2 expression and function. Thus, we aim to establish the relationship between MUC1 and COX-2 expression and determine the mechanism by which MUC1 regulates COX-2 expression. Cell lines: Human BxPC3 and mouse Panc02 PC cell lines that express low endogenous MUC1 were stably transfected with full length MUC1 (MUC1), empty vector (Neo), or full length MUC1 with all 7 tyrosine residues of MUC1 CT mutated to Phenylalanine (Y0). Other cell lines: human HPAFII and Capan-1 and mouse KCM cells that express high endogenous MUC1; and mouse KCKO cells that genetically lack Muc1. Method: We measured the level of COX-2 mRNA and protein by RT-PCR and Western blot respectively. MUC1 was transiently knocked down using a smart pool of MUC1 specific siRNA in MUC1high cells. Immunohistochemistry (IHC) was performed on tumor sections to determine the in situ expression of COX-2 and MUC1. Chromatin immunoprecipitation (ChIP) assay was conducted to evaluate binding of MUC1 CT to the promoter of COX-2 gene. Results: Significantly higher levels of COX-2 mRNA and protein were detected in PC cells expressing high MUC1 compared to cells with low MUC1. This was recapitulated in vivo with higher COX-2 expression in MUC1high versus MUC1low tumors. A subsequent decrease in COX-2 protein was observed upon MUC1 knock down in the MUC1high PC cells. Thus, a direct correlation exists between MUC1 and COX-2 expression in PC cells. Importantly, this correlation was lost in the Y0 cells in which COX-2 expression was significantly decreased even though there was high MUC1 expression. Data clearly suggests that signaling through the tyrosine residues of MUC1 CT is essential for MUC1 induced COX-2 gene expression. Further, in the MUC1high cells, MUC1 CT associates with the COX-2 promoter around 1000 bp upstream of the transcription start site. This association does not occur in the Y0 cells suggesting that an intact CT is necessary for this interaction. Interestingly, MUC1 CT interacts with the COX-2 promoter around the same gene locus where NF-kB associates with the COX-2 promoter. This raises the possibility that MUC1 CT associates with NF-kB via its tyrosine residues and the MUC1/NFkB complex acts as a transcriptional regulator of the COX-2 gene. Citation Format: Sritama Nath, Lopamudra Das Roy, Shanti Rao, Priyanka Grover, Pinku Mukherjee. MUC1 transcriptionally regulates COX-2 gene in pancreatic cancer cells. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 3119. doi:10.1158/1538-7445.AM2013-3119

Introduction: While much advancement has been made in breast cancer treatment, metastatic breast cancer remains an incurable disease. The glycoprotein MUC1 is over-expressed and underglycosylated in over 90% of human breast tumors and 100% of metastatic lesions, and thus was ranked the second most targetable tumor antigen (TA) by NCI. Vaccines against TAs have several benefits, including the chance to eliminate metastatic lesions that express the TA. To this end, we have proposed vaccinating with peptides from the MUC1 protein core, which is only visible to the immune system on the tumor-associated form of the protein. We have previously shown that vaccination does elicit a MUC1-specific immune response that can only be functional if the immunosuppressive tumor microenvironment is blocked to allow efficient tumor cell killing. We investigated the effectiveness of MUC1 vaccination in combination with drugs known to inhibit immunosuppression. Methods: Mice that are transgenic for human MUC1 were orthotopically injected with syngenic breast cancer cells expressing human MUC1. Mice were vaccinated after palpable tumor formation three times in 10 day intervals. Previous work has shown that blocking the cyclooxygenase pathway (COX) resulted in an inhibition of immunosuppression. Thus we treated daily with following drugs in combination with the MUC1-vaccine therapy: Indomethacine (COX1/2 inhibitor), Celecoxib (COX2 inhibitor), 1-methyl tryptophan (IDO inhibitor), and AH6809 (EP2 receptor antagonist). Tumor volume was monitored every day by caliper measurements. Immune activation was measured via an IFN-γ ELISPOT assay using T cells from tumor-draining lymph nodes as responders and dendritic cells pulsed with the vaccinating peptides as simulators. Results: MUC1 vaccine therapy alone causes a slight reduction in tumor burden, although not significant, but does induce IFN-γ production from T cells, indicating immune cell activation. Only the combinational therapy of Vaccine + Indomethacin results in a significant reduction in tumor size. All drugs cause significantly higher levels of IFN-γ production from T cells compared to vaccine alone but no reduction in tumor burden. The combinational treatments of Vaccine + Indomethacine and Vaccine + Celecoxib reduce intra-tumoral PGE2 levels compared to vaccine alone. In a repeat experiment, we found that vaccine alone and indomethacin alone caused a slight reduction in tumor burden, but tumor burden was only significantly reduced when the therapy was given in combination. Conclusion: In this model, MUC1 vaccine efficacy can be enhanced when given in combination with Indomethacin. Since Indomethacin but not Celecoxib reduced tumor burden when given in combination with the MUC1 vaccine, we suggest that Indomethacin enhanced vaccine efficacy via a COX-independent pathway. Future experiments will explore this mechanism. Citation Format: Jennifer M. Curry, Dahlia M. Besmer, Lopamudra Das Roy, Priyanka Grover, Sritama Nath, Shanti Rao, Pinku Mukherjee. Combinational treatment with MUC1 vaccine and Indomethacin reduces breast tumor burden via a COX-independent pathway. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 475. doi:10.1158/1538-7445.AM2013-475

Introduction: Pancreatic ductal adenocarcinoma (PDA) has the worst prognosis of all cancers and is the fourth leading cause of cancer-related deaths in the United States. Cancer stem cells (CSCs), which are a small population of tumor cells that have the ability to self-renew and differentiate into the diverse cells that comprise the tumor, have been identified in pancreatic cancer patients as lineage-negative, CD133 (prominin-1)-expressing cells. In pancreatic cancer, MUC1 is a protein expressed with a high frequency and its expression correlates with high metastasis and poor prognosis. Recent reports from our lab have demonstrated the ability of MUC1 to drive epithelial-to-mesenchymal transition thus producing a cell with ‘stem-like’ properties. We therefore investigated the correlation between MUC1 expression and CSCs. Methods: Primary tumor tissues surgically resected from patients diagnosed with pancreatic adenocarcinoma (n=8) and human pancreatic cancer cell lines were assessed for CD133 and MUC1 expression by flow cytometry. Results: In pancreatic cancer patients, tumor MUC1 levels correlated with a higher percentage of CD133-expressing cells (R=0.76). Similarly, in MiaPaCa2, Capan-1, BxPC3 WT, BxPC3 MUC1, Su86.86 WT and Su86.86 MUC1 cells lines, MUC1 levels correlated with increased CD133 expression (R=0.83). The majority of CD133+ cells isolated from primary human pancreatic tumors (82.6 ± 12.7%) expressed MUC1. Similar results were obtained using cell lines, as 83.22 ± 30.9% of CD133-expressing cells were MUC1-positive. Conclusion: MUC1 is present on the majority of CSCs and its expression correlates with higher levels of cancer stem cells. This study demonstrates yet another oncogenic role of MUC1 in pancreatic cancer progression and suggests MUC1 as a novel marker for CSCs. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 2454. doi:10.1158/1538-7445.AM2011-2454

Introduction: Pancreatic cancer is the fourth leading cause of cancer-related death in United States. Most human pancreatic cancers overexpress MUC1, which is associated with high metastasis and poor prognosis of the disease. We have recently shown that MUC1 initiates the process of epithelial to mesenchymal transition (EMT) and promotes metastasis in pancreatic cancer cells via signaling through the seven tyrosines present in its cytoplasmic tail (CT) motif. When the 7 tyrosines were mutated to phenylalanine, EMT was completely abrogated. Since TGF-β has been extensively studied as a mediator of EMT and invasion in pancreatic cancer, we hypothesized that MUC1 may be inducing its effect through regulating TGF-β production and signaling. We also aimed at identifying the specific tyrosine residue(s) responsible for MUC1 induced EMT. Method: We made the following plasmids containing a) full length MUC1 (MUC1), b) all 7 tyrosine residues of MUC1 CT were mutated to Phenylalanine (Y0), c) Y6 (Tyrosine 6 present, the rest replaced by Phenylalanine), d) Y7 (Tyrosine 7 present, the rest replaced by Phenylalanine), e) Y2,5 (Tyrosine 2 and 5 present, the rest replaced by Phenylalanine), f) Y3,6,7 (Tyrosine3, 6 and 7 present, the rest replaced by Phenylalanine) and g) empty vector (Neo). These plasmids were stably expressed in human pancreatic cancer cell lines, BxPC3 and Su86.86 that express low levels of endogenous MUC1. We first assessed the levels of functional TGF-β secreted by BxPC3 Neo, MUC1 and Y0 cells as well as the levels of TGF-βI and II receptors. We then treated these cells with exogenous human recombinant TGF-β and assessed both, the process of EMT and the capacity to invade through growth-reduced matrigel. Results: We found that BxPC3.MUC1 cells produced strikingly larger amounts of TGF-β compared to BxPC3 Neo and Y0 cells. We also found that MUC1-expressing cells became more invasive in response to exogenous TGF-β while the Y0 cells did not respond to exogenous TGF-β although the receptor levels were similar in all three cell lines. However, none of the mutants of MUC1 CT could rescue the function of full length MUC1, in the context of induction of EMT. Conclusion: 1) We believe that TGF-β mediated EMT and TGF-β signal propagation requires the tyrosine residue of MUC1, which is evident from the data that mutating the tyrosine residues in MUC1CT abrogates TGF-β mediated EMT in these cells. 2) Induction of EMT by MUC1 is a complex process, which involves a particular combination of tyrosine residues of MUC1. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 2910. doi:10.1158/1538-7445.AM2011-2910