>1.2 million people in the United States have a personal history of melanoma skin cancer and are at increased risk for disease recurrence and second primary melanomas. Many of these individuals do not follow recommendations to conduct regular, thorough skin self-examinations that facilitate early disease detection and do not sufficiently engage in sun protection behaviors.
View Article and Find Full Text PDFOur research group demonstrated that riluzole, an inhibitor of glutamatergic signaling reduced melanoma cell proliferation in vitro and tumor progression in vivo. The underlying mechanisms of riluzole are largely unknown. Microarray analyses on two human melanoma cell lines revealed that riluzole stimulates expression of the cystine-glutamate amino acid antiporter, xCT (SLC7A11).
View Article and Find Full Text PDFStudies demonstrate that GRM, expressed by >60% of human melanomas, may be a therapeutic target. We performed a phase II trial of 100 mg PO bid of riluzole, an inhibitor of GRM1 signaling, in patients with advanced melanoma with the primary endpoint of response rate. Thirteen patients with GRM1-positive tumors were enrolled.
View Article and Find Full Text PDFExosomes are naturally occurring membrane-bound nanovesicles generated constitutively and released by various cell types, and often in higher quantities by tumor cells. Exosomes may facilitate communication between the primary tumor and its local microenvironment, supporting cell invasion and other early events in metastasis. A neuronal receptor, metabotropic glutamate receptor 1 (GRM1), when ectopically expressed in melanocytes, induces melanocytic transformation and spontaneous malignant melanoma development in a transgenic mouse model.
View Article and Find Full Text PDFBackground/objectives: Skin cancer incidence has been increasing in U.S. Hispanics over several decades and the postdiagnosis outcomes are worse for Hispanics than for non-Hispanic whites.
View Article and Find Full Text PDFJ Clin Oncol
April 2016
Purpose: The Sunbelt Melanoma Trial is a prospective randomized trial evaluating the role of high-dose interferon alfa-2b therapy (HDI) or completion lymph node dissection (CLND) for patients with melanoma staged by sentinel lymph node (SLN) biopsy.
Patients And Methods: Patients were eligible if they were age 18 to 70 years with primary cutaneous melanoma ≥ 1.0 mm Breslow thickness and underwent SLN biopsy.
Acral lentiginous melanoma (ALM) is a rare subtype of melanoma mainly arising on the palms, soles, and nail beds. ALM is the most common subtype of melanoma found in patients of Asian or African descent and tends to more advanced at presentation due to delays in diagnosis. Surgical treatment is difficult owing to the complexity and functional importance of the hands and feet and reconstruction after resection is usually needed.
View Article and Find Full Text PDFBackground: Occupational ultraviolet radiation (UVR) exposure is a risk factor for skin cancer, and Hispanic individuals are over-represented in a number of outdoor occupations (e.g., farming, landscaping).
View Article and Find Full Text PDFMany melanoma patients do not regularly perform thorough skin self-examinations. We examined the extent to which melanoma patients conduct thorough skin self-examination, how they perform skin self-examination, and their related knowledge and self-efficacy. A sample of 176 individuals (61.
View Article and Find Full Text PDFOur group has previously reported that the majority of human melanomas (>60%) express the metabotropic glutamate receptor 1 (GRM1) and that the glutamate release inhibitor riluzole, a drug currently used to treat amyotrophic lateral sclerosis, can induce apoptosis in GRM1-expressing melanoma cells. Our group previously reported that in vitro riluzole treatment reduces cell growth in three-dimensional (3D) soft agar colony assays by 80% in cells with wildtype phosphoinositide 3-kinase (PI3K) pathway activation. However, melanoma cell lines harboring constitutive activating mutations of the PI3K pathway (PTEN and NRAS mutations) showed only a 35% to 40% decrease in colony formation in soft agar in the presence of riluzole.
View Article and Find Full Text PDFWe report the case of an interdigitating dendritic cell sarcoma (IDCS) presenting in the skin. A 41-year old woman had a slowly enlarging mass on her right scapula that was excised multiple times under a presumptive diagnosis of a recurrent sebaceous cyst. However, the lesion was refractory to standard therapies.
View Article and Find Full Text PDFApproximately 50% of patients having metastatic melanoma develop brain metastases during the course of their illness. Evidence exists that melanoma cells have increased aptitude for the repair of sublethal DNA damage caused by ionizing radiation therapy. To address the radio-resistance of melanoma, many groups adopted radiotherapy schedules that deliver larger daily fractions of radiation, but due to the risk of neurotoxicity, these large fractions cannot be delivered to the whole brain for patients with brain metastases.
View Article and Find Full Text PDFFibroblast growth factor (FGF2) regulates endothelial and melanoma cell migration. The binding of FGF2 to its receptor requires N-sulfated heparan sulfate (HS) glycosamine. We have previously reported that Epac1, an exchange protein activated by cAMP, increases N-sulfation of HS in melanoma.
View Article and Find Full Text PDFIn the present study, we investigated the role of the transcription factor RUNX2 in melanomagenesis. We demonstrated that the expression of transcriptionally active RUNX2 was increased in melanoma cell lines as compared with human melanocytes. Using a melanoma tissue microarray, we showed that RUNX2 levels were higher in melanoma cells as compared with nevic melanocytes.
View Article and Find Full Text PDFStore-operated Ca(2+) entry (SOCE) is a major mechanism of Ca(2) (+) import from extracellular to intracellular space, involving detection of Ca(2+) store depletion in endoplasmic reticulum (ER) by stromal interaction molecule (STIM) proteins, which then translocate to plasma membrane and activate Orai Ca(2+) channels there. We found that STIM1 and Orai1 isoforms were abundantly expressed in human melanoma tissues and multiple melanoma/melanocyte cell lines. We confirmed that these cell lines exhibited SOCE, which was inhibited by knockdown of STIM1 or Orai1, or by a pharmacological SOCE inhibitor.
View Article and Find Full Text PDFGlutamate-triggered signal transduction is thought to contribute widely to cancer pathogenesis. In melanoma, overexpression of the metabotropic glutamate receptor (GRM)-1 occurs frequently and its ectopic expression in melanocytes is sufficient for neoplastic transformation. Clinical evaluation of the GRM1 signaling inhibitor riluzole in patients with advanced melanoma has demonstrated tumor regressions that are associated with a suppression of the mitogen-activated protein kinase (MAPK) and phosphoinositide 3-kinase/protein kinase B (PI3K/AKT) pathways.
View Article and Find Full Text PDFTNBC is an aggressive breast cancer subtype that does not express hormone receptors (estrogen and progesterone receptors, ER and PR) or amplified human epidermal growth factor receptor type 2 (HER2), and there currently exist no targeted therapies effective against it. Consequently, finding new molecular targets in triple negative breast cancer (TNBC) is critical to improving patient outcomes. Previously, we have detected the expression of metabotropic glutamate receptor-1 (gene: GRM1; protein: mGluR1) in TNBC and observed that targeting glutamatergic signaling inhibits TNBC growth both in vitro and in vivo.
View Article and Find Full Text PDFGain of function of the neuronal receptor, metabotropic glutamate receptor 1 (Grm1), was sufficient to induce melanocytic transformation in vitro and spontaneous melanoma development in vivo when ectopically expressed in melanocytes. The human form of this receptor, GRM1, has been shown to be ectopically expressed in a subset of human melanomas but not benign nevi or normal melanocytes, suggesting that misregulation of GRM1 is involved in the pathogenesis of certain human melanomas. Sustained stimulation of Grm1 by the ligand, glutamate, is required for the maintenance of transformed phenotypes in vitro and tumorigenicity in vivo.
View Article and Find Full Text PDFObjective: To examine the association between linguistic acculturation (assessed using the Language Use and Linguistic Preference subscales from the Bidimensional Acculturation Scale for Hispanics) and skin cancer-related behaviors among US Hispanic adults to determine whether, compared with Hispanics denoted as Spanish-acculturated, English-acculturated Hispanics would report less frequent shade seeking and use of sun protective clothing and higher rates of sunscreen use, sunbathing, and indoor tanning.
Design: Online survey study conducted in September 2011.
Setting: Five southern and western US states.
Background: Little skin cancer prevention research has focused on the US Hispanic population.
Objective: This study examined the prevalence and correlates of skin cancer surveillance behaviors among Hispanic adults.
Methods: A population-based sample of 788 Hispanic adults residing in 5 southern and western states completed an online survey in English or Spanish in September 2011.
Background: Skin cancer prevention interventions that target the growing number of U.S. Hispanics are lacking.
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