First-Generation Radiolabeled Cyclic Peptides for Molecular Imaging of Platelet-Derived Growth Factor Receptor α.

Occult nodal spread and metastatic disease require longstanding imaging and biochemical assessments for thyroid cancer, a disease that has a propensity for diffuse, small-volume disease. We have developed a Cu-labeled platelet-derived growth factor receptor α (PDGFRA) antibody for immuno-PET of PDGFRA in metastatic papillary thyroid cancer (PTC). The present work describes the discovery of small cyclic PDGFRA-targeting peptides, their binding features, and radiolabeling with positron emitter gallium-68 (Ga) for characterization in thyroid cancer models.

Lipid phosphate phosphatase-2 promotes tumor growth through increased c-Myc expression.

LPP2 is one of three enzymes in the lipid phosphate phosphatase family (LPP1-3) that dephosphorylate extracellular and intracellular bioactive lipid phosphates and pyrophosphates. LPP2 increases cell growth and LPP2 expression is elevated in a variety of malignancies, implying that LPP2 is a pro-tumorigenic factor. LPP2 expression in human breast tumors and normal breast tissue was measured by qPCR.

Human Cytomegalovirus Seropositivity and Viral DNA in Breast Tumors Are Associated with Poor Patient Prognosis.

Human cytomegalovirus (HCMV) infects 40-70% of adults in developed countries. Detection of HCMV DNA and/or proteins in breast tumors varies considerably, ranging from 0-100%. In this study, nested PCR to detect HCMV glycoprotein B (gB) DNA in breast tumors was shown to be sensitive and specific in contrast to the detection of DNA for immediate early genes.

Depletion of essential fatty acids in muscle is associated with shorter survival of cancer patients undergoing surgery-preliminary report.

Emerging studies are reporting associations between skeletal muscle abnormalities and survival in cancer patients. Cancer prognosis is associated with depletion of essential fatty acids in erythrocytes and plasma in humans. However the relationship between skeletal muscle membrane fatty acid composition and survival is unknown.

PDGFRα Enhanced Infection of Breast Cancer Cells with Human Cytomegalovirus but Infection of Fibroblasts Increased Prometastatic Inflammation Involving Lysophosphatidate Signaling.

Human cytomegalovirus (HCMV) infects 40-70% of adults in developed countries. HCMV proteins and DNA are detected in tumors and metastases, suggesting an association with increased invasion. We investigated HCMV infection in human breast cancer cell lines compared to fibroblasts, a component of tumors, and the role of platelet-derived growth factor receptor-α (PDGFRα).

Positron Emission Tomography Imaging of Autotaxin in Thyroid and Breast Cancer Models Using [F]PRIMATX.

Autotaxin (ATX) is a secreted enzyme responsible for producing lysophosphatidic acid (LPA). The ATX/LPA signaling axis is typically activated in wound healing and tissue repair processes. The ATX/LPA axis is highjacked and upregulated in the progression and persistence of several chronic inflammatory diseases, including cancer.

is Differentially Expressed Across Breast Cancer Subtypes with Low Expression Associated with Poor Overall Survival.

Purpose: Forkhead box Q1 () has been shown to contribute to the development and progression of cancers, including ovarian and breast cancer (BC). However, research exploring expression, copy number variation (CNV), and prognostic value across different BC subtypes is limited. Our purpose was to evaluate mRNA expression, CNV, and prognostic value across BC subtypes.

Gene expression profile of epithelial-mesenchymal transition mediators in papillary thyroid cancer.

Purpose: Platelet derived growth receptor alpha (PDGFRA) promotes the epithelial-mesenchymal transition (EMT) in thyroid follicular cells and is linked to lymphatic metastases in papillary thyroid cancer (PTC). We probed the regulatory network of genes linked to PDGFRA and EMT, comparing matched patient primary tumor and metastatic specimens, as well as engineered cell lines and ex vivo primary cultures with and without PDGFRA.

Methods: Freshly isolated thyroid tumors with or without metastases, with matching neighboring benign or normal tissue, was isolated for comparative transcriptional analysis using a TaqMan Low Density array (TLDA) assay with genes representing important markers of EMT, cellular adhesion, apoptosis, differentiation, senescence, and signal transduction pathways in thyroid cancer.

Tyrosine kinase inhibitor therapy and metabolic remodelling in papillary thyroid cancer.

Targeted therapy is increasingly used to manage metastatic papillary thyroid cancer. The focus of the present study was to examine glucose metabolism and tumor responses for thyroid cancer xenografts expressing the glycolytic pathway modulators platelet-derived growth factor receptor (PDGFR) and BRAFV600E. Radiolabelled glucose derivative [18F]FDG was used to analyze the effects of PDGFR blockade with imatinib, BRAF blockade with vemurafenib, as well as combined PDGFR and BRAF blockade in vitro and in vivo with PET.

BIK drives an aggressive breast cancer phenotype through sublethal apoptosis and predicts poor prognosis of ER-positive breast cancer.

Apoptosis is fundamental to normal animal development and is the target for many anticancer therapies. Recent studies have explored the consequences of "failed apoptosis" where the apoptotic program is initiated but does not go to completion and does not cause cell death. Nevertheless, this failed apoptosis induces DNA double-strand breaks generating mutations that facilitate tumorigenesis.

Dexamethasone Attenuates X-Ray-Induced Activation of the Autotaxin-Lysophosphatidate-Inflammatory Cycle in Breast Tissue and Subsequent Breast Fibrosis.

We recently showed that radiation-induced DNA damage in breast adipose tissue increases autotaxin secretion, production of lysophosphatidate (LPA) and expression of LPA receptors. We also established that dexamethasone decreases autotaxin production and LPA signaling in non-irradiated adipose tissue. In the present study, we showed that dexamethasone attenuated the radiation-induced increases in autotaxin activity and the concentrations of inflammatory mediators in cultured human adipose tissue.

Lipid is heterogeneously distributed in muscle and associates with low radiodensity in cancer patients.

Background: Low muscle radiodensity is associated with mortality in a variety of cancer types. Biochemical and morphological correlates are unknown. We aimed to evaluate triglyceride (TG) content and location as a function of computed tomography (CT)-derived measures of skeletal muscle radiodensity in cancer patients.

Repeated Fractions of X-Radiation to the Breast Fat Pads of Mice Augment Activation of the Autotaxin-Lysophosphatidate-Inflammatory Cycle.

Breast cancer patients are usually treated with multiple fractions of radiotherapy (RT) to the whole breast after lumpectomy. We hypothesized that repeated fractions of RT would progressively activate the autotaxin-lysophosphatidate-inflammatory cycle. To test this, a normal breast fat pad and a fat pad containing a mouse 4T1 tumor were irradiated with X-rays using a small-animal "image-guided" RT platform.

Increasing the low lipid phosphate phosphatase 1 activity in breast cancer cells decreases transcription by AP-1 and expressions of matrix metalloproteinases and cyclin D1/D3.

Metastasis is the leading cause of mortality in breast cancer patients and lysophosphatidate (LPA) signaling promotes this process. LPA signaling is attenuated by lipid phosphate phosphatase-1 (LPP1) whose activity is decreased in cancers. Consequently, increasing LPP1 levels suppresses breast tumor growth and metastasis.

Active surveillance of low-risk papillary thyroid cancer: A meta-analysis.

Background: This study evaluates the safety and efficacy of active surveillance for low-risk papillary thyroid carcinoma.

Methods: MEDLINE, EMBASE, and PubMed were searched from inception for relevant studies of active surveillance for low-risk papillary thyroid carcinoma, defined as T1a or T1b, N0, M0 disease. Main outcomes of interest were growth of primary tumor, metastatic spread, thyroid cancer-related mortality, and disease recurrence after delayed thyroid surgery.

Immunohistochemical phenotyping of T cells, granulocytes, and phagocytes in the muscle of cancer patients: association with radiologically defined muscle mass and gene expression.

Background: Inflammation is a recognized contributor to muscle wasting. Research in injury and myopathy suggests that interactions between the skeletal muscle and immune cells confer a pro-inflammatory environment that influences muscle loss through several mechanisms; however, this has not been explored in the cancer setting. This study investigated the local immune environment of the muscle by identifying the phenotype of immune cell populations in the muscle and their relationship to muscle mass in cancer patients.

Clinical and biological characterization of skeletal muscle tissue biopsies of surgical cancer patients.

Background: Researchers increasingly use intraoperative muscle biopsy to investigate mechanisms of skeletal muscle atrophy in patients with cancer. Muscles have been assessed for morphological, cellular, and biochemical features. The aim of this study was to conduct a state-of-the-science review of this literature and, secondly, to evaluate clinical and biological variation in biopsies of rectus abdominis (RA) muscle from a cohort of patients with malignancies.

Loss of nuclear localization of thyroid transcription factor 1 and adverse outcomes in papillary thyroid cancer.

Function of the thyroid follicular cell depends on nuclear expression of thyroid transcription factor 1 (TTF1). Regulation of this key protein regulating iodide transport is not well known, but its loss is linked to the most lethal of thyroid malignancies. We examined TTF1 nuclear expression in the context of adverse pathological features, disease recurrence, and BRAF status in papillary thyroid carcinomas with (n = 182) and without (n = 303) nodal metastases.

Efficacy of 177Lu Peptide Receptor Radionuclide Therapy for the Treatment of Neuroendocrine Tumors: A Meta-analysis.

Objective: The purpose of this study was to assess the efficacy of Lu-labeled peptide receptor radionuclide therapy (PRRT) induction treatments for patients with unresectable metastatic neuroendocrine tumors.

Methods: MEDLINE, EMBASE, and Ovid were systematically searched with keywords "lutetium," "Lu-177," "PRRT," "neuroendocrine," and "prognosis." Studies evaluating treatment with Lu-labeled PRRT were assessed for disease response and/or disease control rate by Response Evaluation Criteria in Solid Tumors (RECIST) 1.

Dexamethasone decreases the autotaxin-lysophosphatidate-inflammatory axis in adipose tissue: implications for the metabolic syndrome and breast cancer.

Lysophosphatidate (LPA) signaling through 6 receptors is regulated by the balance of LPA production by autotaxin (ATX) vs. LPA degradation by lipid phosphate phosphatases (LPPs). LPA promotes an inflammatory cycle by increasing the synthesis of cyclooxygenase-2 and multiple inflammatory cytokines that stimulate further ATX production.

Low-Activity Radioactive Iodine Therapy for Thyroid Carcinomas Exhibiting Nodal Metastases and Extrathyroidal Extension May Lead to Early Disease Recurrence.

Background: The application of radioactive iodine in differentiated thyroid carcinomas has become more selective in an attempt to decrease morbidity. While ablative success has been documented, it is less clear how changes in radioactive iodine treatment strategies will influence long-term recurrence rates for patients with larger tumors and adverse pathological features, including extrathyroidal extension and nodal metastases.

Methods: Patients diagnosed between 1995 and 2008 with differentiated thyroid carcinoma treated with thyroidectomy followed by radioactive iodine treatment were eligible.

Coming of Age for Autotaxin and Lysophosphatidate Signaling: Clinical Applications for Preventing, Detecting and Targeting Tumor-Promoting Inflammation.

A quarter-century after the discovery of autotaxin in cell culture, the autotaxin-lysophosphatidate (LPA)-lipid phosphate phosphatase axis is now a promising clinical target for treating chronic inflammatory conditions, mitigating fibrosis progression, and improving the efficacy of existing cancer chemotherapies and radiotherapy. Nearly half of the literature on this axis has been published during the last five years. In cancer biology, LPA signaling is increasingly being recognized as a central mediator of the progression of chronic inflammation in the establishment of a tumor microenvironment which promotes cancer growth, immune evasion, metastasis, and treatment resistance.

Autocrine activation of platelet-derived growth factor receptor α in metastatic papillary thyroid cancer.

Metastatic dissemination of papillary thyroid cancer has been reported to be strongly associated with expression of platelet-derived growth factor (PDGFR) α and altered TTF1 function. However, the status of PDGF ligands in papillary thyroid cancer and the potential role of these ligands in metastatic disease are obscure. We assessed the prevalence of PDGF ligands in benign and malignant thyroid tumors to determine if ligand upregulation is associated with α-isoform (PDGF-AA or PDGF-BB) or the β-isoform (PDGF-BB or PDGF-DD) of PDGFR in individual tumors.

Molecular imaging of platelet-derived growth factor receptor-alpha (PDGFRα) in papillary thyroid cancer using immuno-PET.

Introduction: Receptor tyrosine kinase (RTK) platelet-derived growth factor receptor-alpha (PDGFRα) was recently identified as a molecular switch for dedifferentiation in thyroid cancer that predicts resistance to therapy as well as recurrence of disease in papillary thyroid cancer. Here we describe the radiolabeling and functional characterization of an imaging probe based on a PDGFRα-specific monoclonal antibody (mAb) for immuno-PET imaging of PDGFRα in papillary thyroid cancer.

Methods: Antibody D13C6 (Cell Signaling) was decorated with chelator NOTA using bioconjugation reaction with 2-(p-NCS-Bz)-NOTA.

Normal human adipose tissue functions and differentiation in patients with biallelic inactivating mutations.

Lipin-1 is a Mg-dependent phosphatidic acid phosphatase (PAP) that in mice is necessary for normal glycerolipid biosynthesis, controlling adipocyte metabolism, and adipogenic differentiation. Mice carrying inactivating mutations in the gene display the characteristic features of human familial lipodystrophy. Very little is known about the roles of lipin-1 in human adipocyte physiology.