Notch1 blockade by a novel, selective anti-Notch1 neutralizing antibody improves immunotherapy efficacy in melanoma by promoting an inflamed TME.

Background: Immune checkpoint inhibitors (ICI) have dramatically improved the life expectancy of patients with metastatic melanoma. However, about half of the patient population still present resistance to these treatments. We have previously shown Notch1 contributes to a non-inflamed TME in melanoma that reduces the response to ICI.

Targeting extracellular matrix remodeling sensitizes glioblastoma to ionizing radiation.

Background: The median survival of Glioblastoma multiforme (GBM) patients is 14+ months due to poor responses to surgery and chemoradiation. Means to counteract radiation resistance are therefore highly desirable. We demonstrate the membrane bound matrix metalloproteinase MT1-MMP promotes resistance of GBM to radiation, and that using a selective and brain permeable MT1-MMP inhibitor, -ND336, improved tumor control can be achieved in preclinical studies.

MT1-MMP-dependent ECM processing regulates laminB1 stability and mediates replication fork restart.

Radiotherapy remains a mainstay of treatment for a majority of cancer patients. We have previously shown that the membrane bound matrix metalloproteinase MT1-MMP confers radio- and chemotherapy resistance to breast cancer via processing of the ECM and activation of integrinβ1/FAK signaling. Here, we further discovered that the nuclear envelope protein laminB1 is a potential target of integrinβ1/FAK.

Wound Healing Assay for Melanoma Cell Migration.

Cell migration is a critical process involved in morphogenesis, inflammation, and cancer metastasis. Wound healing assay is a simple, non-expensive, and highly reproducible method to study cancer cell migration in vitro. It is based on the observation that cells growing in a monolayer migrate to re-establish cell contacts after the development of an artificial wound.

The biology of human hair greying.

Hair greying (canities) is one of the earliest, most visible ageing-associated phenomena, whose modulation by genetic, psychoemotional, oxidative, senescence-associated, metabolic and nutritional factors has long attracted skin biologists, dermatologists, and industry. Greying is of profound psychological and commercial relevance in increasingly ageing populations. In addition, the onset and perpetuation of defective melanin production in the human anagen hair follicle pigmentary unit (HFPU) provides a superb model for interrogating the molecular mechanisms of ageing in a complex human mini-organ, and greying-associated defects in bulge melanocyte stem cells (MSCs) represent an intriguing system of neural crest-derived stem cell senescence.

Targeting Extracellular Matrix Remodeling Restores BRAF Inhibitor Sensitivity in BRAFi-resistant Melanoma.

Purpose: The extracellular matrix (ECM) is an intriguing, yet understudied component of therapy resistance. Here, we investigated the role of ECM remodeling by the collagenase, MT1-MMP, in conferring resistance of v-Raf murine sarcoma viral oncogene homolog B1 (BRAF)-mutant melanoma to BRAF inhibitor (BRAFi) therapy.

Experimental Design: Publicly available RNA-sequencing data and reverse phase protein array were used to determine the relevance of MT1-MMP upregulation in BRAFi-resistant melanoma in patients, patient-derived xenografts, and cell line-derived tumors.

Hair(y) Matters in Melanoma Biology.

Melanocyte stem cells (MeSCs), one candidate for the cellular origin of melanoma, reside in the bulge region of the hair follicle (HF), an immune-privileged tissue niche with impaired tumor immunosurveillance. Surprisingly, however, primary melanoma is only very rarely associated with HFs. Here, we explore the hypothesis that this profoundly immunoinhibitory signaling environment deprives both MeSCs and melanocytes of the anagen hair matrix of proinflammatory signals required for full oncogenic transformation.

Blockade of CCR5 in melanoma: An alternative immune checkpoint modulator.

Melanoma is a deadly tumor, which in recent years has been successfully treated with immune checkpoint inhibitors as PD-1/PD-L1 and CTLA-4 inhibitors and targeted therapy as BRAF and MEK inhibitors. However, immunotherapy poses deleterious side effects and pursuit of new therapeutic targets is warranted. As knowledge of tumor immunology advances, such targets are being recognized.

ErbB3 Phosphorylation as Central Event in Adaptive Resistance to Targeted Therapy in Metastatic Melanoma: Early Detection in CTCs during Therapy and Insights into Regulation by Autocrine Neuregulin.

In recent years the introduction of target therapies with BRAF and MEK inhibitors (MAPKi) and of immunotherapy with anti-CTLA-4 and anti-PD-1 monoclonal antibodies have dramatically improved survival of metastatic melanoma patients. Despite these changes drug resistance remains a major hurdle. Several mechanisms are at the basis of drug resistance.

The membrane tethered matrix metalloproteinase MT1-MMP triggers an outside-in DNA damage response that impacts chemo- and radiotherapy responses of breast cancer.

Breast cancer is the second leading cause of death among women in the US. Targeted therapies exist, however resistance is common and patients resort to chemotherapy. Chemotherapy is also a main treatment for triple negative breast cancer (TNBC) patients; while radiation is delivered to patients with advanced disease to counteract metastasis.

Inhibiting Notch1 enhances immunotherapy efficacy in melanoma by preventing Notch1 dependent immune suppressive properties.

We have previously shown that Notch1 plays a critical role in modulating melanoma tumor cell growth and survival. Here we show that Notch1 also contributes to an immune-suppressive tumor microenvironment (TME). Notch1 inhibition reduces immune suppressive cells (i.

The natural compound fucoidan from New Zealand Undaria pinnatifida synergizes with the ERBB inhibitor lapatinib enhancing melanoma growth inhibition.

Melanoma remains one of the most aggressive and therapy-resistant cancers. Finding new treatments to improve patient outcomes is an ongoing effort. We previously demonstrated that melanoma relies on the activation of ERBB signaling, specifically of the ERBB3/ERBB2 cascade.

Cellular Prion Protein Mediates Pancreatic Cancer Cell Survival and Invasion through Association with and Enhanced Signaling of Notch1.

Up-regulation of human prion protein (PrP) in patients with pancreatic ductal adenocarcinoma (PDAC) is associated with a poor prognosis. However, the underlying molecular mechanism of PrP-mediated tumorigenesis is not completely understood. In this study, we found that PDAC cell lines can be divided into either PrP high expresser or PrP low expresser.

The thiirane-based selective MT1-MMP/MMP2 inhibitor ND-322 reduces melanoma tumor growth and delays metastatic dissemination.

MT1-MMP and MMP2 have been implicated as pro-tumorigenic and pro-metastatic factors in a wide variety of cancers including melanoma. We have previously demonstrated that MT1-MMP is highly expressed in melanoma where it promotes melanoma cell invasion and metastasis in part through the activation of its target MMP2. Given the accessibility of MMPs, as they are either secreted (e.

The membrane tethered matrix metalloproteinase MT1-MMP at the forefront of melanoma cell invasion and metastasis.

The Extracellular Matrix (ECM) plays an important role in normal physiological development and functioning of cells, tissues and organs [1]. Under normal physiological conditions degradation of the ECM is a finely regulated process, and altered homeostasis of ECM degradation (excessive or insufficient) is associated with many diseases [2-5] such as cancer, fibrosis, arthritis, nephritis, encephalomyelitis and chronic ulcers. The remodeling of the ECM is carried out by a family of enzymes known as matrix metalloproteinases (MMP).

Synchronized Targeting of Notch and ERBB Signaling Suppresses Melanoma Tumor Growth through Inhibition of Notch1 and ERBB3.

Despite significant advances in melanoma therapy, melanoma remains the deadliest form of skin cancer, with a 5-year survival rate of only 15%. Thus, novel treatments are required to address this disease. Notch and ERBB are evolutionarily conserved signaling cascades required for the maintenance of melanocyte precursors.

MT1-MMP dependent repression of the tumor suppressor SPRY4 contributes to MT1-MMP driven melanoma cell motility.

Metastatic melanoma is the deadliest of all skin cancers. Despite progress in diagnostics and treatment of melanoma, the prognosis for metastatic patients remains poor. We previously showed that Membrane-type 1 Matrix Metalloproteinase (MT1-MMP) is one of the drivers of melanoma metastasis.

Notch1 Autoactivation via Transcriptional Regulation of Furin, Which Sustains Notch1 Signaling by Processing Notch1-Activating Proteases ADAM10 and Membrane Type 1 Matrix Metalloproteinase.

Notch1 is an evolutionarily conserved transmembrane receptor involved in melanoma growth. Notch1 is first cleaved by furin in the Golgi apparatus to produce the biologically active heterodimer. Following ligand binding, Notch1 is cleaved at the cell membrane by proteases such as ADAM10 and -17 and membrane type 1 matrix metalloproteinase (MT1-MMP), the latter of which we recently identified as a novel protease involved in Notch1 processing.

Noncanonical activation of Notch1 protein by membrane type 1 matrix metalloproteinase (MT1-MMP) controls melanoma cell proliferation.

Notch1 is an evolutionarily conserved signaling molecule required for stem cell maintenance that is inappropriately reactivated in several cancers. We have previously shown that melanomas reactivate Notch1 and require its function for growth and survival. However, no Notch1-activating mutations have been observed in melanoma, suggesting the involvement of other activating mechanisms.

MT1-MMP modulates melanoma cell dissemination and metastasis through activation of MMP2 and RAC1.

Metastatic melanoma remains the deadliest of all skin cancers with a survival rate at five years of less than 15%. MT1-MMP is a membrane-associated matrix metalloproteinase that controls pericellular proteolysis and is an important, invasion-promoting, pro-tumorigenic MMP in cancer. We show that deregulation of MT1-MMP expression happens as early as the transition from nevus to primary melanoma and continues to increase during melanoma progression.

The apoptosis repressor with a CARD domain (ARC) gene is a direct hypoxia-inducible factor 1 target gene and promotes survival and proliferation of VHL-deficient renal cancer cells.

The induction of hypoxia-inducible factors (HIFs) is essential for the adaptation of tumor cells to a low-oxygen environment. We found that the expression of the apoptosis inhibitor ARC (apoptosis repressor with a CARD domain) was induced by hypoxia in a variety of cancer cell types, and its induction is primarily HIF1 dependent. Chromatin immunoprecipitation (ChIP) and reporter assays also indicate that the ARC gene is regulated by direct binding of HIF1 to a hypoxia response element (HRE) located at bp -190 upstream of the transcription start site.

Notch signaling in melanoma: interacting pathways and stromal influences that enhance Notch targeting.

The Notch signaling pathway is an evolutionarily conserved, intercellular signaling cascade. Notch was first described in the early 1900s when a mutant Drosophila showed notches on the wing margins. Studies of the role of Notch signaling have ever since flourished, and the pleiotropic nature of the Notch gene is now evident.

An ERBB3/ERBB2 oncogenic unit plays a key role in NRG1 signaling and melanoma cell growth and survival.

We recently identified neuregulin-1 (NRG1) as a novel target of Notch1 required in Notch-dependent melanoma growth. ERBB3 and ERBB4, tyrosine kinase receptors specifically activated by NRG1, have been shown to be either elevated in melanoma cell lines and tumors or to be mutated in 20% of melanomas, respectively. While these data support key roles of NRG1 and its receptors in the pathogenesis of melanoma, whether ERBB3 and ERBB4 display redundant or exclusive functions is not known.

VHL loss in renal cell carcinoma leads to up-regulation of CUB domain-containing protein 1 to stimulate PKC{delta}-driven migration.

A common genetic mutation found in clear cell renal cell carcinoma (CC-RCC) is the loss of the von Hippel-Lindau (VHL) gene, which results in stabilization of hypoxia-inducible factors (HIFs), and contributes to cancer progression and metastasis. CUB-domain-containing protein 1 (CDCP1) was shown to promote metastasis in scirrhous and lung adenocarcinomas as well as in prostate cancer. In this study, we established a molecular mechanism linking VHL loss to induction of the CDCP1 gene through the HIF-1/2 pathway in renal cancer.