Background: Many tumors contain hypoxic microenvironments caused by inefficient tumor vascularization. Hypoxic tumors have been shown to resist conventional cancer therapies. Hypoxic cancer cells rely on glucose to meet their energetic and anabolic needs to fuel uncontrolled proliferation and metastasis.
View Article and Find Full Text PDFMetabolic dysfunction-associated steatotic liver disease (MASLD) has surpassed the hepatitis B virus and hepatitis C virus as the leading cause of chronic liver disease in most parts of the Western world. MASLD (formerly known as NAFLD) encompasses both simple steatosis and more aggressive metabolic dysfunction-associated steatohepatitis (MASH), which is accompanied by inflammation, fibrosis, and cirrhosis, and ultimately can lead to hepatocellular carcinoma (HCC). There are currently very few approved therapies for MASH.
View Article and Find Full Text PDFBackground: Many tumors contain hypoxic microenvironments caused by inefficient tumor vascularization. Hypoxic tumors have been shown to resist conventional cancer therapies. Hypoxic cancer cells rely on glucose to meet their energetic and anabolic needs to fuel uncontrolled proliferation and metastasis.
View Article and Find Full Text PDFThe MYC proto-oncogene (MYC) is one of the most frequently overexpressed genes in breast cancer that drives cancer stem cell-like traits, resulting in aggressive disease progression and poor prognosis. In this study, we identified zinc finger transcription factor 148 (ZNF148, also called Zfp148 and ZBP-89) as a direct target of MYC. ZNF148 suppressed cell proliferation and migration and was transcriptionally repressed by MYC in breast cancer.
View Article and Find Full Text PDFBranched-chain amino acids (BCAAs) are the three essential amino acids including leucine, isoleucine, and valine. BCAA metabolism has been linked with the development of a variety of tumors. However, the impact of dietary BCAA intake on breast tumor progression and metastasis remains to be fully explored.
View Article and Find Full Text PDFAlthough immunotherapy has revolutionized cancer treatment, many immunogenic tumors remain refractory to treatment. This can be largely attributed to an immunologically "cold" tumor microenvironment characterized by an accumulation of immunosuppressive myeloid cells and exclusion of activated T cells. Here, we demonstrate that genetic ablation or therapeutic inhibition of the myeloid-specific hematopoietic cell kinase (HCK) enables activity of antagonistic anti-programmed cell death protein 1 (anti-PD1), anti-CTLA4, or agonistic anti-CD40 immunotherapies in otherwise refractory tumors and augments response in treatment-susceptible tumors.
View Article and Find Full Text PDFHepatocellular carcinoma (HCC) is the fifth most common cancer worldwide. Serine-arginine rich splicing factor 3 (SRSF3) plays a critical role in hepatocyte function and its loss in mice promotes chronic liver damage and leads to HCC. Hepatocyte-specific SRSF3 knockout mice (SKO mice) also overexpress insulin-like growth factor 2 (IGF2).
View Article and Find Full Text PDFAccumulating evidence indicates that obesity with its associated metabolic dysregulation, including hyperinsulinemia and aberrant circadian rhythms, increases the risk for a variety of cancers including postmenopausal breast cancer. Caloric restriction can ameliorate the harmful metabolic effects of obesity and inhibit cancer progression but is difficult to implement and maintain outside of the clinic. In this study, we aim to test a time-restricted feeding (TRF) approach on mouse models of obesity-driven postmenopausal breast cancer.
View Article and Find Full Text PDFPurpose: To investigate how induced tumor heterogeneity influences immune responses to radiotherapy with different proportions of mixed immune-responsive and unresponsive tumor cells in a triple-negative breast cancer model. It is hypothesized that studying the immune environment of mixed tumors and responses to radiotherapy could nominate immune active therapies to enhance immune responses after radiotherapy.
Experimental Design: Evaluate efficacy and immune responses generated by radiotherapy in tumors with different proportions of immunologically responsive and unresponsive tumor cells.
Serine rich splicing factor 3 (SRSF3) plays a critical role in liver function and its loss promotes chronic liver damage and regeneration. As a consequence, genetic deletion of SRSF3 in hepatocytes caused progressive liver disease and ultimately led to hepatocellular carcinoma. Here we show that SRSF3 is decreased in human liver samples with non-alcoholic fatty liver disease (NAFLD), non-alcoholic steatohepatitis (NASH), or cirrhosis that was associated with alterations in RNA splicing of known SRSF3 target genes.
View Article and Find Full Text PDFMatrix metalloproteinases-2 and -9 (MMP-2/-9) are key tissue remodeling enzymes that have multiple overlapping activities critical for wound healing and tumor progression in vivo. To overcome issues of redundancy in studying their functions in vivo, we created MMP-2/-9 double knockout (DKO) mice in the C57BL/6 background to examine wound healing. We then bred the DKO mice into the polyomavirus middle T (PyVmT) model of breast cancer to analyze the role of these enzymes in tumorigenesis.
View Article and Find Full Text PDFBreast cancer remains the leading cause of cancer death in women owing to metastasis and the development of resistance to established therapies. Macrophages are the most abundant immune cells in the breast tumor microenvironment and can both inhibit and support cancer progression. Thus, gaining a better understanding of how macrophages support cancer could lead to the development of more effective therapies.
View Article and Find Full Text PDFEvidence of cancer immunosurveillance and immunoediting processes has been primarily demonstrated in mouse models of chemically induced oncogenesis. Although these models are very tractable, they are characterized by high mutational loads that represent a minority of human cancers. In this study, we sought to determine whether cancer immunosurveillance and immunoediting could be demonstrated in a more clinically relevant oncogene-induced model of carcinogenesis, the MMTV-PyMT (PyMT) mammary carcinoma model.
View Article and Find Full Text PDFIncreasing evidence suggests that ionizing radiation therapy (RT) in combination with checkpoint immunotherapy is highly effective in treating a subset of cancers. To better understand the limited responses to this combination we analysed the genetic, microenvironmental, and immune factors in tumours derived from a transgenic breast cancer model. We identified two tumours with similar growth characteristics but different RT responses primarily due to an antitumour immune response.
View Article and Find Full Text PDFBackground: Menopause is associated with significant hormonal changes that result in increased total body fat and abdominal fat, amplifying the risk for metabolic syndrome and diseases such as diabetes, cardiovascular disease and cancer in postmenopausal women. Intermittent fasting regimens hold significant health benefit promise for obese humans, however, regimens that include extreme daytime calorie restriction or daytime fasting are generally associated with hunger and irritability, hampering long-term compliance and adoption in the clinical setting. Time-restricted feeding (TRF), a regimen allowing eating only during a specific period in the normal circadian feeding cycle, without calorie restriction, may increase compliance and provide a more clinically viable method for reducing the detrimental metabolic consequences associated with obesity.
View Article and Find Full Text PDFObesity is associated with an increased risk of developing breast cancer and is also associated with worse clinical prognosis. The mechanistic link between obesity and breast cancer progression remains unclear, and there has been no development of specific treatments to improve the outcome of obese cancer patients. Here we show that obesity-associated NLRC4 inflammasome activation/ interleukin (IL)-1 signalling promotes breast cancer progression.
View Article and Find Full Text PDFMacrophages infiltrate cancers and promote progression to invasion and metastasis. To directly examine tumor-associated macrophages (TAMs) and tumor cells interacting and co-migrating in a three-dimensional (3D) environment, we have developed a co-culture model that uses a PyVmT mouse mammary tumor-derived cell line and mouse bone marrow-derived macrophages (BMM). The Py8119 cell line was cloned from a spontaneous mammary tumor in a Tg(MMTV:LTR-PyVmT) C57Bl/6 mouse and these cells form 3-dimensional (3D) spheroids under conditions of low adhesion.
View Article and Find Full Text PDF1. Leukotriene B4 (LTB4) is a proinflammatory mediator important in the progression of a number of inflammatory diseases. Preclinical models can explore the role of LTB4 in pathophysiology using tool compounds, such as CP-105696, that modulate its activity.
View Article and Find Full Text PDFMyeloid-derived suppressor cells (MDSCs) are a heterogeneous population of immature cells that expand during benign and cancer-associated inflammation and are characterized by their ability to inhibit T cell immunity. Increased metabolism of l-Arginine (l-Arg), through the enzymes arginase 1 and NO synthase 2 (NOS2), is well documented as a major MDSC suppressive mechanism. Therefore, we hypothesized that restricting MDSC uptake of l-Arg is a critical control point to modulate their suppressor activity.
View Article and Find Full Text PDFBreast Cancer Res
October 2015
Introduction: The diversity of human breast cancer subtypes has led to the hypothesis that breast cancer is actually a number of different diseases arising from cells at various stages of differentiation. The elusive nature of the cell(s) of origin thus hampers approaches to eradicate the disease.
Methods: Clonal cell lines were isolated from primary transgenic polyomavirus middle T (PyVmT) luminal tumors.
Metastatic spread is the leading cause of cancer mortality. Breast cancer (BCa) metastatic recurrence can happen years after removal of the primary tumor. Here we show that Ubc13, an E2 enzyme that catalyzes K63-linked protein polyubiquitination, is largely dispensable for primary mammary tumor growth but is required for metastatic spread and lung colonization by BCa cells.
View Article and Find Full Text PDFBackground: High intensity-focused ultrasound (HIFU) is an alterative ablative technique currently being investigated for local treatment of breast cancer and fibroadenomas. Current HIFU therapies require concurrent magnetic resonance imaging monitoring. Biodegradable 500 nm perfluoropentane-filled iron-silica nanoshells have been synthesized as a sensitizing agent for HIFU therapies, which aid both mechanical and thermal ablation of tissues.
View Article and Find Full Text PDFActivatable cell-penetrating peptides (ACPP) provide a general strategy for molecular targeting by exploiting the extracellular protease activities associated with disease. Previous work used a matrix metalloproteinase (MMP-2 and 9)-cleavable sequence in the ACPP to target contrast agents for tumor imaging and fluorescence-guided surgery. To improve specificity and sensitivity for MMP-2, an integrin α(v)β(3)-binding domain, cyclic-RGD, was covalently linked to the ACPP.
View Article and Find Full Text PDFPrevious studies have suggested that TGF-β functions as a tumor promoter in metastatic, mesenchymal-like breast cancer cells and that TGF-β inhibitors can effectively abrogate tumor progression in several of these models. Here we report a novel observation with the use of genetic and pharmacological approaches, and murine mammary cell injection models in both syngeneic and immune compromised mice. We found that TGF-β receptor II (TβRII) knockdown in the MMTV-PyMT derived Py8119, a mesenchymal-like murine mammary tumor cell line, resulted in increased orthotopic tumor growth potential in a syngeneic background and a similar trend in an immune compromised background.
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