Expression of β-catenin and cyclin D1 in Merkel cell carcinomas of the head and neck

The biology and treatment of Merkel cell carcinoma: current understanding and research priorities

Merkel cell carcinoma (MCC) is a rare and aggressive skin cancer associated with advanced age and immunosuppression. Over the past decade, an association has been discovered between MCC and either integration of the Merkel cell polyomavirus, which likely drives tumorigenesis, or somatic mutations owing to ultraviolet-induced DNA damage. Both virus-positive and virus-negative MCCs are immunogenic, and inhibition of the programmed cell death protein 1 (PD-1)–programmed cell death 1 ligand 1 (PD-L1) immune checkpoint has proved to be highly effective in treating patients with metastatic MCC; however, not all patients have a durable response to immunotherapy. Despite these rapid advances in the understanding and management of patients with MCC, many basic, translational and clinical research questions remain unanswered. In March 2018, an International Workshop on Merkel Cell Carcinoma Research was held at the US National Cancer Institute, at which academic, government and industry experts met to identify the highest-priority research questions. Here, we review the biology and treatment of MCC and report the consensus-based recommendations agreed upon during the workshop.

Merkel cell carcinoma (MCC) is a rare and aggressive form of nonmelanoma skin cancer. The availability of immune checkpoint inhibition has improved the outcomes of a subset of patients with MCC, although many unmet needs continue to exist. In this Consensus Statement, the authors summarize developments in our understanding of MCC while also providing consensus recommendations for future research.

MicroRNA-216a suppresses the proliferation and migration of human breast cancer cells via the Wnt/β-catenin signaling pathway

The aim of the present study was to investigate the potential anticancer effects of microRNA-216a on the growth of human breast cancer and the possible underlying mechanisms. The results demonstrated that serum microRNA-216a was significantly decreased in patients with breast cancer compared with healthy controls. MicroRNA-216a overexpression led to a decrease in cell proliferation and migration, as well as increases in apoptosis, caspase-3/8 activities, Bax expression and p53 protein expression in MCF-7 cells. It was also revealed that microRNA-216a suppressed Wnt and β-catenin expression in MCF-7 cells. The anticancer effects of microRNA-216a were reversed by anti-microRNA-216a by promoting the Wnt/β-catenin signaling pathway. Inactivation of the Wnt pathway increased the anticancer effects of microRNA-216a in MCF-7 cells. Collectively, the results of the present study indicated that microRNA-216a suppressed the growth of human breast cancer cells by targeting the Wnt/β-catenin signaling pathway.

T cell therapies for human polyomavirus diseases

Rapid restoration of virus-specific T immunity via adoptive transfer of ex vivo generated T cells has been proven as a powerful therapy for patients with advanced cancers and refractory viral infections such as cytomegalovirus (CMV) and Epstein-Barr virus (EBV). BK virus (BKV), John Cunningham virus (JCV), and Merkel cell carcinoma virus (MCV) are the members of the rapidly growing human polyomavirus (hPyV) family that commonly infects most healthy humans. These viruses have a clearly established potential for causing severe end-organ damage or malignant transformation, especially in individuals with weakened immunity who are unable to mount or regain endogenous T-cell responses as a result of underlying leukemia or iatrogenic immunosuppression in autoimmunity, bone marrow and solid organ transplant settings. Here we will discuss recent advances in using T-cell-based immunotherapies to save patients suffering from PyV-associated diseases including hemorrhagic cystitis, BKV virus-associated nephropathy, and JC-associated progressive multifocal leukoencephalopathy (PML). We will also review progress in the understanding of Merkel cell carcinoma (MCC) as a virally driven tumor that is amenable to immune intervention and can be targeted with adoptively transferred T cells specific for viral oncoproteins.

Molecular characteristics and potential therapeutic targets in Merkel cell carcinoma

Merkel cell carcinoma (MCC) is an aggressive neuroendocrine skin tumour occurring preferentially in elderly and immunosuppressed individuals. Multiple studies have provided insight into the molecular alterations of MCC, leading to the design of several ongoing clinical trials testing chemotherapy, targeted therapy and immunotherapy in patients with recurrent or metastatic disease. The results of some of these studies are available, whereas others are eagerly awaited and will likely shed light on the understanding of MCC biology and potentially improve the clinical outcomes of patients with this rare disease.

Mutational analysis of merkel cell carcinoma

Merkel cell carcinoma (MCC) is an aggressive cutaneous neuroendocrine malignancy that is associated with a poor prognosis. The pathogenesis of MCC is not well understood, and despite a recent plethora of mutational analyses, we have yet to find a set of signature mutations implicated in the majority of cases. Mutations, including TP53, Retinoblastoma and PIK3CA, have been documented in subsets of patients. Other mechanisms are also likely at play, including infection with the Merkel cell polyomavirus in a subset of patients, dysregulated immune surveillance, epigenetic alterations, aberrant protein expression, posttranslational modifications and microRNAs. In this review, we summarize what is known about MCC genetic mutations and chromosomal abnormalities, and their clinical significance. We also examine aberrant protein function and microRNA expression, and discuss the therapeutic and prognostic implications of these findings. Multiple clinical trials designed to selectively target overexpressed oncogenes in MCC are currently underway, though most are still in early phases. As we accumulate more molecular data on MCC, we will be better able to understand its pathogenic mechanisms, develop libraries of targeted therapies, and define molecular prognostic signatures to enhance our clinicopathologic knowledge.

Correlation of β-catenin, but not PIN1 and cyclin D1, overexpression with disease-free and overall survival in patients with cancer of the parotid gland

BACKGROUND

Malignant tumors of the salivary glands comprise about 3% to 5% of all head and neck carcinomas. The purpose of our study was to find possible predictive and/or prognostic markers for parotid cancer.

METHODS

A total of 46 tissue samples of carcinomas of the parotid gland were immunohistochemically stained for ß-catenin, cyclin D1, and PIN1. The factors were analyzed regarding their prognostic value for disease-free and overall survival.

RESULTS

An overexpression of the cytoplasmatic ß-catenin was linked to a statistically significant worse outcome regarding disease-free (p = .0296) and overall survival (p = .0416). The 5-year overall survival was 83.9% in patients without and 0% in patients presenting with overexpression of cytoplasmatic ß-catenin. Additionally, Union Internationale Contre le Cancer (UICC) stage correlated with overall survival (p = .0306) and disease-free survival (DFS; p = .0473).

CONCLUSION

Multivariate analysis showed that overexpression of cytoplasmatic ß-catenin and the UICC stage are 2 independent prognostic markers for survival in patients with parotid cancer.