Berta L Sánchez-Laorden

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The melanogenic actions of the melanocortins are mediated by the melanocortin-1 receptor (MC1R). MC1R is a member of the G-protein-coupled receptors (GPCR) superfamily expressed in cutaneous and hair follicle melanocytes. Activation of MC1R by adrenocorticotrophin or alpha-melanocyte stimulating hormone is positively coupled to the cAMP signaling pathway(More)
UNLABELLED We generated cell lines resistant to BRAF inhibitors and show that the EGF receptor (EGFR)-SRC family kinase (SFK)-STAT3 signaling pathway was upregulated in these cells. In addition to driving proliferation of resistant cells, this pathway also stimulated invasion and metastasis. EGFR inhibitors cooperated with BRAF inhibitors to block the(More)
Progressive kidney fibrosis contributes greatly to end-stage renal failure, and no specific treatment is available to preserve organ function. During renal fibrosis, myofibroblasts accumulate in the interstitium of the kidney, leading to massive deposition of extracellular matrix and organ dysfunction. The origin of myofibroblasts is manifold, but the(More)
We show that in melanoma cells oncogenic BRAF, acting through MEK and the transcription factor BRN2, downregulates the cGMP-specific phosphodiesterase PDE5A. Although PDE5A downregulation causes a small decrease in proliferation, its major impact is to stimulate a dramatic increase in melanoma cell invasion. This is because PDE5A downregulation leads to an(More)
Melanoma is a highly metastatic and lethal form of skin cancer. The protein kinase BRAF is mutated in about 40% of melanomas, and BRAF inhibitors improve progression-free and overall survival in these patients. However, after a relatively short period of disease control, most patients develop resistance because of reactivation of the RAF-ERK (extracellular(More)
The melanocortin 1 receptor (MC1R), a G(S)-protein-coupled receptor (GPCR), is a key regulator of proliferation and differentiation of epidermal melanocytes, and a determinant of human skin phototype and cancer risk. Homodimerization has been demonstrated for several GPCRs, but little information is available for MC1R. SDS-PAGE analysis of melanoma cells(More)
BRAF and MEK inhibitors are effective in BRAF mutant melanoma, but most patients eventually relapse with acquired resistance, and others present intrinsic resistance to these drugs. Resistance is often mediated by pathway reactivation through receptor tyrosine kinase (RTK)/SRC-family kinase (SFK) signaling or mutant NRAS, which drive paradoxical(More)
Ornithine decarboxylase (ODC) and the antizyme inhibitors (AZIN1 and AZIN2), regulatory proteins of polyamine levels, are antizyme-binding proteins. Although it is widely recognized that ODC is mainly a cytosolic enzyme, less is known about the subcellular distribution of AZIN1 and AZIN2. We found that these proteins, which share a high degree of homology(More)
The melanocortin 1 receptor (MC1R), a Gs protein-coupled receptor (GPCR) expressed in melanocytes, is a major determinant of skin pigmentation and phototype. MC1R activation stimulates melanogenesis and increases the ratio of black, strongly photoprotective eumelanins to reddish, poorly photoprotective pheomelanins. Several MC1R alleles are associated with(More)
Cutaneous melanoma is epidemiologically linked to ultraviolet radiation (UVR), but the molecular mechanisms by which UVR drives melanomagenesis remain unclear. The most common somatic mutation in melanoma is a V600E substitution in BRAF, which is an early event. To investigate how UVR accelerates oncogenic BRAF-driven melanomagenesis, we used a BRAF(V600E)(More)