Is oestrogen an important player in melanoma progression?

Is Melanoma Progression Affected by Thyroid Diseases?

Clinical and epidemiological evidence indicate a relationship between thyroid diseases and melanoma. In particular, the hypothyroidism condition appears to promote melanoma spread, which suggests a protective role of thyroid hormones against disease progression. In addition, experimental data suggest that, in addition to thyroid hormones, other hormonal players of the hypothalamic–pituitary–thyroid (HPT) axis, namely the thyrotropin releasing hormone and the thyrotropin, are likely to affect melanoma cells behavior. This information warrants further clinical and experimental studies in order to build a precise pattern of action of the HPT hormones on melanoma cells. An improved knowledge of the involved molecular mechanism(s) could lead to a better and possibly personalized clinical management of these patients.

The Sex-Related Interplay between TME and Cancer: On the Critical Role of Estrogen, MicroRNAs and Autophagy

The interplay between cancer cells and the tumor microenvironment (TME) has a fundamental role in tumor progression and response to therapy. The plethora of components constituting the TME, such as stroma, fibroblasts, endothelial and immune cells, as well as macromolecules, e.g., hormones and cytokines, and epigenetic factors, such as microRNAs, can modulate the survival or death of cancer cells. Actually, the TME can stimulate the genetically regulated programs that the cell puts in place under stress: apoptosis or, of interest here, autophagy. However, the implication of autophagy in tumor growth appears still undefined. Autophagy mainly represents a cyto-protective mechanism that allows cell survival but, in certain circumstances, also leads to the blocking of cell cycle progression, possibly leading to cell death. Since significant sex/gender differences in the incidence, progression and response to cancer therapy have been widely described in the literature, in this review, we analyzed the roles played by key components of the TME, e.g., estrogen and microRNAs, on autophagy regulation from a sex/gender-based perspective. We focused our attention on four paradigmatic and different forms of cancers-colon cancer, melanoma, lymphoma, and lung cancer-concluding that sex-specific differences may exert a significant impact on TME/cancer interaction and, thus, tumor growth.

Gender Differences and Outcomes in Melanoma Patients

INTRODUCTION

Melanoma is one of the most common cancers in younger people. The incidence of cutaneous melanoma is increasing in patients of both sexes, with female patients generally living longer than their male counterparts. The aim of this retrospective study was to evaluate and confirm the sex-based difference in survival of melanoma patients and the relationship of this difference with pathological features.

METHODS

A total of 1023 patients who had been treated at the Department of Medical Oncology, Università Politecnica Marche (Ancona, Italy) and the INRCA-IRCCS Department of Dermatology (Ancona, Italy) between 1987 and 2014 were enrolled in the study.

RESULTS

In terms of stage of disease at onset, there was a significant difference in disease-free survival (DFS) and overall survival (OS) in favor of female patients in disease stage I (P  = 0.001 and P  = 0.01, respectively) and II (P  = 0.02 and P  = 0.009, respectively). Female patients also showed a significant improvement in 12-year DFS and 12-year OS adjusted for pathological features (Breslow thickness, ulceration, "absent" tumor-infiltrating lymphocyte (TIL) melanomas, "non-brisk" TIL pattern). Globally, female patients had an advantage over with male patients in both DFS and OS (P  < 0.001).

CONCLUSIONS

Our results show that women have a survival benefit over with men after adjustment for many variables that can reduce mortality risk in female melanoma patients. In a future investigation we wish to examine possible biological sex differences in tumor-host interactions.

Ethinylestradiol and Levonorgestrel as Active Agents in Normal Skin, and Pathological Conditions Induced by UVB Exposure: In Vitro and In Ovo Assessments

The link between melanoma development and the use of oral combined contraceptives is not fully elucidated, and the data concerning this issue are scarce and controversial. In the present study, we show that the components of oral contraceptives, ethinylestradiol (EE), levonorgestrel (LNG), and their combination (EE + LNG) ± UVB (ultraviolet B radiation) induced differential effects on healthy (human keratinocytes, fibroblasts, and primary epidermal melanocytes, and murine epidermis cells) and melanoma cells (human—A375 and murine—B164A5), as follows: (i) at low doses (1 µM), the hormones were devoid of significant toxicity on healthy cells, but in melanoma cells, they triggered cell death via apoptosis; (ii) higher doses (10 µM) were associated with cytotoxicity in all cells, the most affected being the melanoma cells; (iii) UVB irradiation proved to be toxic for all types of cells; (iv) UVB irradiation + hormonal stimulation led to a synergistic cytotoxicity in the case of human melanoma cells—A375 and improved viability rates of healthy and B164A5 cells. A weak irritant potential exerted by EE and EE + LNG (10 µM) was assessed by the means of a chick chorioallantoic membrane assay. Further studies are required to elucidate the hormones’ cell type-dependent antimelanoma effect and the role played by melanin in this context.

Polymorphisms in apoptosis-related genes in cutaneous melanoma prognosis: sex disparity

Cutaneous melanoma (CM) cells are resistant to apoptosis, and steroid hormones are involved in this process through regulation of TP53, MDM2, BAX, and BCL2 expression. We analyzed herein sex differences in outcomes of CM patients associated with TP53 c.215G>C, MDM2 c.309T>G, BAX c.-248G>A, and BCL2 c.-717C>A polymorphisms. DNA from 121 men and 116 women patients was analyzed by polymerase chain reaction and enzymatic digestion assays. At 60 months of follow-up, shorter progression-free survival (PFS) was seen in males with MDM2 GG + BCL2 AA (20.0 vs. 62.6%, P = 0.0008) genotype. Men carriers of the genotype had poor PFS (HR 3.78, 95% CI 1.30-11.0) than others. For women, shorter PFS was associated with TP53 GC or CC (61.4 vs. 80.8%, P = 0.01) and TP53 GC or CC + MDM2 TG or GG (59.1 vs. 85.4%, P = 0.01) genotypes at the same time. Women carriers of the genotypes had poor PFS (HR 2.46, 95% CI 1.19-5.09; HR 9.49, 95% CI 1.14-78.50) than others, respectively. Our data present, for the first time, preliminary evidence that inherited abnormalities on TP53, MDM2 and BCL2 genes, enrolled in apoptosis pathways, have a pivotal role in differences of outcomes in women and men with CM.

Neuroendocrinology of the skin

The skin is considered the mirror of the soul and is affected by neurohormonal triggers, especially stress. Hair follicles, keratinocytes, mast cells, melanocytes, and sebocytes all express sex and stress hormones implicating them in a local "hypothalamic-pituitary-adrenal axis." In particular, the peptides corticotropin-releasing hormone (CRH) and neurotensin (NT) have synergistic action stimulating mast cells and are uniquely elevated in the serum of patients with skin diseases exacerbated by stress. Addressing the neurohormonal regulation of skin function could lead to new targets for effective treatment of inflammatory skin diseases.

Tamoxifen Resistance: Emerging Molecular Targets

17β-Estradiol (E2) plays a pivotal role in the development and progression of breast cancer. As a result, blockade of the E2 signal through either tamoxifen (TAM) or aromatase inhibitors is an important therapeutic strategy to treat or prevent estrogen receptor (ER) positive breast cancer. However, resistance to TAM is the major obstacle in endocrine therapy. This resistance occurs either de novo or is acquired after an initial beneficial response. The underlying mechanisms for TAM resistance are probably multifactorial and remain largely unknown. Considering that breast cancer is a very heterogeneous disease and patients respond differently to treatment, the molecular analysis of TAM’s biological activity could provide the necessary framework to understand the complex effects of this drug in target cells. Moreover, this could explain, at least in part, the development of resistance and indicate an optimal therapeutic option. This review highlights the implications of TAM in breast cancer as well as the role of receptors/signal pathways recently suggested to be involved in the development of TAM resistance. G protein—coupled estrogen receptor, Androgen Receptor and Hedgehog signaling pathways are emerging as novel therapeutic targets and prognostic indicators for breast cancer, based on their ability to mediate estrogenic signaling in ERα-positive or -negative breast cancer.

Estrogen Receptor β in Melanoma: From Molecular Insights to Potential Clinical Utility

Cutaneous melanoma is an aggressive tumor; its incidence has been reported to increase fast in the past decades. Melanoma is a heterogeneous tumor, with most patients harboring mutations in the BRAF or NRAS oncogenes, leading to the overactivation of the MAPK/ERK and PI3K/Akt pathways. The current therapeutic approaches are based on therapies targeting mutated BRAF and the downstream pathway, and on monoclonal antibodies against the immune checkpoint blockade. However, treatment resistance and side effects are common events of these therapeutic strategies. Increasing evidence supports that melanoma is a hormone-related cancer. Melanoma incidence is higher in males than in females, and females have a significant survival advantage over men. Estrogens exert their effects through estrogen receptors (ERα and ERβ) that affect cancer growth in an opposite way: ERα is associated with a proliferative action and ERβ with an anticancer effect. ERβ is the predominant ER in melanoma, and its expression decreases in melanoma progression, supporting its role as a tumor suppressor. Thus, ERβ is now considered as an effective molecular target for melanoma treatment. 17β-estradiol was reported to inhibit melanoma cells proliferation; however, clinical trials did not provide the expected survival benefits. In vitro studies demonstrate that ERβ ligands inhibit the proliferation of melanoma cells harboring the NRAS (but not the BRAF) mutation, suggesting that ERβ activation might impair melanoma development through the inhibition of the PI3K/Akt pathway. These data suggest that ERβ agonists might be considered as an effective treatment strategy, in combination with MAPK inhibitors, for NRAS mutant melanomas. In an era of personalized medicine, pretreatment evaluation of the expression of ER isoforms together with the concurrent oncogenic mutations should be considered before selecting the most appropriate therapeutic intervention. Natural compounds that specifically bind to ERβ have been identified. These phytoestrogens decrease the proliferation of melanoma cells. Importantly, these effects are unrelated to the oncogenic mutations of melanomas, suggesting that, in addition to their ERβ activating function, these compounds might impair melanoma development through additional mechanisms. A better identification of the role of ERβ in melanoma development will help increase the therapeutic options for this aggressive pathology.