Faculty Bibliography

BACKGROUND:There is an increasing demand for facial skin rejuvenation. Specialized aesthetic skincare treatments may be one of the first steps to help prevent or treat facial signs of aging. This article discusses aesthetic skin care for facial skin rejuvenation, particularly data on two creams containing Macrocystis pyrifera ferment. METHODS:The authors convened a dermatology advisory board to discuss challenges and practices in using skincare for facial rejuvenation, combining their expert opinion and experience on facial rejuvenation with preclinical and clinical data on two creams containing Macrocystis pyrifera ferment and a review of the literature. RESULTS:Preclinical and clinical studies on Macrocystis pyrifera ferment and two creams containing the ferment exhibit anti-inflammatory, anti-aging, and healing properties. In preclinical studies, the ferment demonstrated collagen type I enhancing properties in ex vivo skin models, and skin cells treated with the ferment migrated faster than untreated cells in the in vitro study. In clinical studies measuring visible anti-inflammatory activity, the ferment alone and the ferment-containing products significantly decreased erythema, and in anti-aging studies, they improved visible skin aging parameters. Finally, in clinical studies on the stratum corneum, the two creams increased moisture levels and decreased transepidermal water loss (TEWL), reflecting healing by enhancing barrier strength and recovery. CONCLUSIONS:The Macrocystis pyrifera ferment and creams containing the ferment are effective skin care treatment products to decrease the visible effects of inflammation and signs of aging while promoting healing by enhancing barrier resilience and recovery.

Endothelin-1 (ET-1) is a vasoactive peptide that also plays a role in the tanning response of the skin. Animal and cell culture studies have also implicated ET-1 in melanoma progression, but no association studies have been performed to link ET-1 expression and melanoma in humans. Here, we present the first in-vivo study of ET-1 expression in pigmented lesions in humans: an ET-1 immunohistochemical screen of melanocytic nevi, melanoma in situ lesions, invasive melanomas, metastatic melanomas, and blue nevi was performed. Twenty-six percent of melanocytic nevi and 44% of melanoma in situ lesions demonstrate ET-1 expression in the perilesional microenvironment, whereas expression in nevus or melanoma cells was rare to absent. In striking contrast, 100% of moderately to highly pigmented invasive melanomas contained numerous ET-1-positive cells in the tumor microenvironment, with 79% containing ET-1-positive melanoma cells, confirmed by co-staining with melanoma tumor marker HMB45. Hypopigmented invasive melanomas had reduced ET-1 expression, suggesting a correlation between ET-1 expression and pigmented melanomas. ET-1-positive perilesional cells were CD68-positive, indicating macrophage origin. Sixty-two percent of highly pigmented metastatic melanomas demonstrated ET-1 expression in melanoma cells, in contrast to 28.2% of hypopigmented specimens. Eighty-nine percent of benign nevi, known as blue nevi, which have a dermal localization, were associated with numerous ET-1-positive macrophages in the perilesional microenvironment, but no ET-1 expression was detected in the melanocytes. We conclude that ET-1 expression in the microenvironment increases with advancing stages of melanocyte transformation, implicating a critical role for ET-1 in melanoma progression, and the importance of the tumor microenvironment in the melanoma phenotype.

Melanoma cell adhesion molecule (MCAM) is upregulated during melanoma progression, and associated with invasion and metastasis. Little is known about the factors that regulate MCAM expression in vivo. Mutations that upregulate MCAM have not been found, and AKT activating mutations are rare in melanomas. This suggests that an epigenetic factor may be responsible for upregulating MCAM and activating AKT in vivo. Although endothelin-1 and endothelin-3 (ET-1, ET-3) are physiologically relevant factors capable of upregulating MCAM in melanocytic cells, a mechanism of action has never been established. Here we show that pharmacologic inhibition of map kinase kinase (MEK) or phosphoinositol 3 kinase (PI3K) blocks MCAM upregulation by ET-3, implicating MEK and PI3K/Akt kinases in ET-3 regulation of MCAM. Despite the fact that there are cAMP response element binding protein (CREB) sites in the MCAM promoter, suppression of CREB expression by siRNA silencing does not block ET-3 mediated upregulation of MCAM. Rather, ET-3 stimulation of melanocytes promotes Akt phosphorylation at Ser 473, which is suppressed by PI3K inhibition or silencing of Akt, in turn blocking ET-3 upregulation of MCAM. We conclude therefore that ETs upregulate MCAM in an Akt and ERK/MEK-dependent, but CREB-independent manner, providing an understanding for possible pharmacologic intervention in progressing melanoma.

The endothelin pathway plays a critical role in melanoma tumor progression by a variety of mechanisms that enhance tumor cell growth, invasion, and metastasis. Here, we investigate the effect of this pathway on CXC chemokine expression in human melanoma cells and melanocytes. As determined by ELISA, endothelin-1 (ET-1) induces CXCL1 and CXCL8 secretion in three human melanoma cell lines in a concentration-dependent fashion. These responses are mediated by the endothelin-B receptor and are sustained over a 40 h time course. ET-1 does not induce CXCL1 secretion in primary human melanocytes but ET-3, an endothelin isoform, induces a low level of CXCL1 secretion in certain cultures. Neither ET-1 nor ET-3 induces secretion of CXCL8 in primary human melanocytes; thus, this response may be specific for melanocytic cells that have undergone malignant transformation. We have previously demonstrated that ET-1 induces changes in the expression of adhesion molecules in melanoma cells such that invasion and metastasis are favored. This study demonstrates that ET-1 additionally induces secretion of CXC chemokines critical for melanoma metastasis and tumor progression

Melanoma cell adhesion molecule (MCAM) is a cell-surface adhesion molecule expressed on over 70% of metastatic melanoma cells but not expressed in normal melanocytes invivo. Protein levels of MCAM correlate with aggressive invasive behavior of melanoma cells in vitro and invivo. Here we demonstrate that endothelin-1 (ET-1) upregulates MCAM protein in primary human melanocytes. MCAM upregulation by ET-1 occurs irrespective of degree of melanocyte pigmentation and is dose-responsive. The drug BQ788 is an endothelin-B (ET(B)) receptor antagonist and inhibits upregulation of MCAM by ET-1. In addition, endothelin-3 (ET-3) and N-succinyl-[Glu9, Ala11, 15]-ET-1-1620, both selective ET(B) agonists, are potent upregulators of MCAM. These demonstrate a critical role for the ET(B) receptor in the upregulation of MCAM by ET-1 and related isoforms. MCAM mRNA abundance is also increased by ET-1 stimulation, thus the mechanism of MCAM protein upregulation may occur at the level of transcription. Our previous studies have demonstrated that ET-1 downregulates E-cadherin in melanocytes and melanoma cells. Since E-cadherin is a melanoma invasion suppressor, and MCAM is a melanoma invasion promoter, ET-1 may promote melanoma invasion and metastasis through the regulation of adhesion molecule expression

Endothelin-1 (ET-1), a peptide that is secreted by keratinocytes in the skin in response to ultraviolet irradiation, is a ligand for the endothelin-B (ET(B)) receptor. Blockade of this receptor inhibits melanoma cell growth and induces cell death in vivo and in vitro. Additionally, ET(B) is a melanoma progression marker. These findings suggest that the ET-1/ET(B) receptor pathway contributes to melanoma development or progression. Here, we demonstrate that activation of the ET-1/ET(B) pathway downregulates E-cadherin and associated catenin proteins in human melanocytes and melanoma cells. E-cadherin is an established suppressor of melanoma cell invasion in vitro and in vivo. Downregulation of E-cadherin by ET-1/ET(B) involves the downstream activation of caspase-8 but not of distal, executioner caspases, and does not lead to apoptosis. ET-1 also induces a transient association between caspase-8 and E-cadherin:beta-catenin complexes. Hence, activation of the ET-1/ET(B) pathway promotes molecular events known to promote melanoma invasion