Inhibition of the receptor tyrosine kinase MerTK by small molecules has the potential to augment the immune response to tumors. Potent, selective inhibitors with high levels of target engagement are needed to fully evaluate the potential use of MerTK inhibitors as cancer therapeutics. We report the discovery and optimization of a series of pyrazinamide-based type 1.
View Article and Find Full Text PDFTAM receptor tyrosine kinases have emerged as promising therapeutic targets for cancer treatment due to their roles in both tumor intrinsic survival mechanisms and suppression of antitumor immunity within the tumor microenvironment. Inhibiting MerTK and Axl selectively is believed to hinder cancer cell survival, reverse the protumor myeloid phenotype, and suppress efferocytosis, thereby eliciting an antitumor immune response. In this study, we present the discovery of , a highly potent and selective dual MerTK/Axl inhibitor, achieved through a structure-based medicinal chemistry campaign.
View Article and Find Full Text PDFDespite increased overall survival rates, curative options for metastatic breast cancer remain limited. We have previously shown that metadherin (MTDH) is frequently overexpressed in poor prognosis breast cancer, where it promotes metastasis and therapy resistance through its interaction with staphylococcal nuclease domain-containing 1 (SND1). Through genetic and pharmacological targeting of the MTDH-SND1 interaction, we reveal a key role for this complex in suppressing antitumor T cell responses in breast cancer.
View Article and Find Full Text PDFMetastatic breast cancer is a leading health burden worldwide. Previous studies have shown that metadherin (MTDH) promotes breast cancer initiation, metastasis and therapy resistance; however, the therapeutic potential of targeting MTDH remains largely unexplored. Here, we used genetically modified mice and demonstrate that genetic ablation of Mtdh inhibits breast cancer development through disrupting the interaction with staphylococcal nuclease domain-containing 1 (SND1), which is required to sustain breast cancer progression in established tumors.
View Article and Find Full Text PDFTumour-initiating cells, or cancer stem cells (CSCs), possess stem-cell-like properties observed in normal adult tissue stem cells. Normal and cancerous stem cells may therefore share regulatory mechanisms for maintaining self-renewing capacity and resisting differentiation elicited by cell-intrinsic or microenvironmental cues. Here, we show that miR-199a promotes stem cell properties in mammary stem cells and breast CSCs by directly repressing nuclear receptor corepressor LCOR, which primes interferon (IFN) responses.
View Article and Find Full Text PDFDNA vaccines have demonstrated antitumor efficacy in multiple preclinical models, but low immunogenicity has been observed in several human clinical trials. This has led to many approaches seeking to improve the immunogenicity of DNA vaccines. We previously reported that a DNA vaccine encoding the cancer-testis antigen SSX2, modified to encode altered epitopes with increased MHC class I affinity, elicited a greater frequency of cytolytic, multifunctional CD8(+) T cells in non-tumor-bearing mice.
View Article and Find Full Text PDFThe Metadherin gene (MTDH) is prevalently amplified in breast cancer and associated with poor prognosis; however, its functional contribution to tumorigenesis is poorly understood. Using mouse models representing different subtypes of breast cancer, we demonstrated that MTDH plays a critical role in mammary tumorigenesis by regulating oncogene-induced expansion and activities of tumor-initiating cells (TICs), whereas it is largely dispensable for normal development. Mechanistically, MTDH supports the survival of mammary epithelial cells under oncogenic/stress conditions by interacting with and stabilizing Staphylococcal nuclease domain-containing 1 (SND1).
View Article and Find Full Text PDFPlasmid DNA serves as a simple and easily modifiable form of antigen delivery for vaccines. The USDA approval of DNA vaccines for several non-human diseases underscores the potential of this type of antigen delivery method as a cost-effective approach for the treatment or prevention of human diseases, including cancer. However, while DNA vaccines have demonstrated safety and immunological effect in early phase clinical trials, they have not consistently elicited robust anti-tumor responses.
View Article and Find Full Text PDFClin Cancer Res
September 2013
Tumor-derived factors can induce a premetastatic niche, yet little is known about how metastatic microenvironments are influenced by external insults, such as acute infections commonly seen in patients with cancer. New findings reveal increased metastasis to the lung after acute bacterial infection via the CXCR4/ubiquitin axis, suggesting new targets for antimetastasis therapeutics.
View Article and Find Full Text PDFTumor metastasis is driven not only by the accumulation of intrinsic alterations in malignant cells, but also by the interactions of cancer cells with various stromal cell components of the tumor microenvironment. In particular, inflammation and infiltration of the tumor tissue by host immune cells, such as tumor-associated macrophages, myeloid-derived suppressor cells, and regulatory T cells, have been shown to support tumor growth in addition to invasion and metastasis. Each step of tumor development, from initiation through metastatic spread, is promoted by communication between tumor and immune cells via the secretion of cytokines, growth factors, and proteases that remodel the tumor microenvironment.
View Article and Find Full Text PDFIntroduction: The aim of this study was to assess the rate of tooth movement and discomfort experienced by orthodontic patients using a vibrational appliance (Tooth Masseuse).
Methods: In this randomised controlled trial (RCT), 66 consecutive patients were assigned to a control or experimental group. The experimental group was instructed to use a vibrational appliance for a minimum of 20 minutes per day.
State and federal actions to conserve northern spotted owl (Strix occidentalis caurina) habitat are largely initiated by establishing habitat occupancy. Northern spotted owl occupancy is typically assessed by eliciting their response to simulated conspecific vocalizations. However, proximity of barred owls (Strix varia)-a significant threat to northern spotted owls-can suppress northern spotted owl responsiveness to vocalization surveys and hence their probability of detection.
View Article and Find Full Text PDFCTLA-4 blockade has demonstrated antitumor efficacy in human clinical trials. The antitumor mechanism is presumably mediated in part by the expansion of tumor-specific T cells. Androgen deprivation, the cornerstone of treatment for patients with metastatic prostate cancer, has been shown to elicit prostate tissue apoptosis and lymphocytic inflammation.
View Article and Find Full Text PDFThe cancer-testis antigen synovial sarcoma X breakpoint-2 (SSX-2) is a potentially attractive target for tumor immunotherapy based upon its tissue-restricted expression to germline cells and its frequent expression in malignancies. The goal of this study was to evaluate genetic vaccine encoding SSX-2 to prioritize human leukocyte antigen (HLA)-A2-specific epitopes and determine if a DNA vaccine can elicit SSX-2-specific cytotoxic T lymphocytes (CTLs) capable of lysing prostate cancer cells. HLA-A2-restricted epitopes were identified based on their in vitro binding affinity for HLA-A2 and by the ability of a genetic vaccine to elicit peptide-specific CTL in A2/DR1 (HLA-A2.
View Article and Find Full Text PDFRecent U.S. Food and Drug Administration approval of the first immunotherapy for prostate cancer encourages efforts to improve immune targeting of this disease.
View Article and Find Full Text PDFBackground: We retrospectively explored changes in immunological parameters in men with biochemically recurrent prostate cancer treated with either 5 or 25 mg of lenalidomide in a randomized phase 2 trial, and determined whether those changes correlated with disease progression.
Methods: Cytokine levels were compared for each patient at baseline and after 6 months of treatment with lenalidomide. Regression models for correlated data were used to assess associations of cytokine levels with lenalidomide treatment effect.
The use of scat surveys to obtain DNA has been well documented in temperate areas, where DNA preservation may be more effective than in tropical forests. Samples obtained in the tropics are often exposed to high humidity, warm temperatures, frequent rain and intense sunlight, all of which can rapidly degrade DNA. Despite these potential problems, we demonstrate successful mtDNA amplification and sequencing for faeces of carnivores collected in tropical conditions and quantify how sample condition and environmental variables influence the success of PCR amplification and species identification.
View Article and Find Full Text PDFWe previously demonstrated that IgG responses to a panel of 126 prostate tissue-associated antigens are common in patients with prostate cancer. In the current report we questioned whether changes in IgG responses to this panel might be used as a measure of immune response, and potentially antigen spread, following prostate cancer-directed immune-active therapies. Sera were obtained from prostate cancer patients prior to and three months following treatment with androgen deprivation therapy (n = 34), a poxviral vaccine (n = 31), and a DNA vaccine (n = 21).
View Article and Find Full Text PDFMost protected areas are too small to sustain populations of wide-ranging mammals; thus, identification and conservation of high-quality habitat for those animals outside parks is often a high priority, particularly for regions where extensive land conversion is occurring. This is the case in the vicinity of Emas National Park, a small protected area in the Brazilian Cerrado. Over the last 40 years the native vegetation surrounding the park has been converted to agriculture, but the region still supports virtually all of the animals native to the area.
View Article and Find Full Text PDFClin Dev Immunol
February 2011
Cancer-testis antigens (CTAs) represent an expanding class of tumor-associated proteins defined on the basis of their tissue-restricted expression to testis or ovary germline cells and frequent ectopic expression in tumor tissue. The expression of CTA in MHC class I-deficient germline cells makes these proteins particularly attractive as immunotherapeutic targets because they serve as essentially tumor-specific antigens for MHC class I-restricted CD8+ T cells. Moreover, because CTAs are expressed in many types of cancer, any therapeutic developed to target these antigens might have efficacy for multiple cancer types.
View Article and Find Full Text PDFThe K homology (KH) domain is a conserved sequence present in a wide variety of RNA-binding proteins. The rough sheath2-interacting KH domain (RIK) protein of maize has been implicated in the maintenance of the repressed chromatin state of knox genes during leaf primordia initiation. The amino acid sequences of the publicly available plant RIK proteins contain a splicing factor 1 (SF1)-like KH domain core sequence motif that distinguishes them from all other SF1-like KH domain-containing proteins.
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