Cornelia Mauch

Merkel Cell Polyomavirus DNA in Persons without Merkel Cell Carcinoma

Merkel cell polyomavirus (MCPyV) DNA was detected in 88% of Merkel cell carcinomas in contrast to 16% of other skin tumors. MCPyV was also found in anogenital and oral samples (31%) and eyebrow hairs (50%) of HIV-positive men and in forehead swabs (62%) of healthy controls. MCPyV thus appears to be widespread.

Role of postoperative radiotherapy in the management of merkel cell carcinoma

Merkel cell carcinoma (MCC) is a rare, aggressive neuroendocrine tumor of the skin with a high potential of locoregional relapse after surgery alone. This report is an update of our experience in the treatment of MCC. From January 1990 to May 2000, 31 patients with MCC, 13 men and 18 women aged between 34 and 92 years, were treated at the University of Cologne, Germany. Primary tumor sites were in the head and neck region in 13 patients, limbs in 13, and trunk in 5. The tumors were stage I in 26 of 31 patients, stage II in 4 of 31 and stage III in 1 of 31. Treatment included surgery alone in 14 of 31 patients, adjuvant postoperative radiotherapy in 16 of 31 patients, 1 of them had incomplete surgery, and definitive radiotherapy in 1 of 31 patients (stage III). Median overall survival (OS) after first diagnosis was 32 months (95% confidence interval: 0-75 months) with a 3-year OS rate of 47% (95% CI: 25-69%). Six of 31 patients relapsed locally after a median of 4 months, 10 of 31 patients developed regional node metastases, and 7 of 31 patients distant metastases. Nine patients died as a direct result of MCC. Locoregional control and disease-free survival were significantly improved in the group with postoperative radiotherapy (p = 0.023). Uni- and multivariate analysis revealed that head and neck location of the tumor and the lack of postoperative radiotherapy are unfavorable prognostic factors. Postoperative radiotherapy to the primary tumor region and the regional lymphatics is effective in the prevention of locoregional recurrence. Prospective clinical trials should be performed to confirm these observations.

Mast cells play a protumorigenic role in primary cutaneous lymphoma

Primary cutaneous lymphomas (PCLs) are clonal T- or B-cell neoplasms, which originate in the skin. In recent years, mast cells were described as regulators of the tumor microenvironment in different human malignancies. Here, we investigated the role of mast cells in the tumor microenvironment of PCL. We found significantly increased numbers of mast cells in skin biopsies from patients with cutaneous T-cell lymphoma (CTCL) and cutaneous B-cell lymphoma (CBCL). Mast cell infiltration was particularly prominent in the periphery, at lymphoma rims. Interestingly, CTCL and CBCL patients with a progressive course showed higher mast cell counts than stable patients, and mast cell numbers in different stages of CTCL correlated positively with disease progression. In addition, mast cell numbers positively correlated with microvessel density. Incubating primary CTCL cells with mast cell supernatant, we observed enhanced proliferation and production of cytokines. In line with our in vitro experiments, in a mouse model of cutaneous lymphoma, tumor growth in mast cell-deficient transgenic mice was significantly decreased. Taken together, these experiments show that mast cells play a protumorigenic role in CTCL and CBCL. Our data provide a rationale for exploiting tumor-associated mast cells as a prognostic marker and therapeutic target in PCL.

Local Tumor Treatment in Combination with Systemic Ipilimumab Immunotherapy Prolongs Overall Survival in Patients with Advanced Malignant Melanoma.

Too few patients benefit from immune checkpoint inhibition alone. However, patients with melanoma receiving systemic anti-CTLA-4 plus localized treatments had significantly prolonged overall survival. In a multivariate analysis, adding local treatment was an independent factor for improved survival. Immune checkpoint inhibition with ipilimumab has revolutionized cancer immunotherapy and significantly improved outcomes of patients with advanced malignant melanoma. Local peripheral treatments (LPT), such as radiotherapy or electrochemotherapy, have been shown to modulate systemic immune responses, and preliminary data have raised the hypothesis that the combination of LPT with systemic immune checkpoint blockade might be beneficial. Clinical data from 127 consecutively treated melanoma patients at four cancer centers in Germany and Switzerland were analyzed. Patients received either ipilimumab (n = 82) or ipilimumab and additional LPT (n = 45) if indicated for local tumor control. The addition of LPT to ipilimumab significantly prolonged overall survival (OS; median OS 93 vs. 42 weeks, unadjusted HR, 0.46; P = 0.0028). Adverse immune-related events were not increased by the combination treatment, and LPT-induced local toxicities were in most cases mild. In a multivariable Cox regression analysis, we show that the effect of added LPT on OS remained statistically significant after adjusting for BRAF status, tumor stage, tumor burden, and central nervous system metastases (adjusted HR, 0.56; 95% confidence interval, 0.31–1.01, P = 0.05). Our data suggest that the addition of LPT to ipilimumab is safe and effective in patients with metastatic melanoma irrespective of clinical disease characteristics and known risk factors. Induction of antitumor immune responses is most likely the underlying mechanism and warrants prospective validation. Cancer Immunol Res; 4(9); 744–54. ©2016 AACR.

A decreased ratio between serum levels of the antagonistic angiopoietins 1 and 2 indicates tumour progression of malignant melanoma.

The growth of solid tumours like malignant melanoma depends on the ability of neoplastic cells to induce angiogenesis to ensure sufficient supply with nutrients and oxygen. The process of angiogenesis is tightly controlled by positive and negative regulators. Since many of these factors can be measured in the serum of patients, their use as tumour markers has been suggested. The angiopoietins 1 and 2 have been demonstrated to be secreted by various tumour cells. By binding to the Tie-2 receptor on endothelial cells, they regulate angiogenesis. Whereas angiopoietin-1 maintains quiescence of vessels, angiopoietin-2 increases angiogenesis by destabilising vessels and sensitising them to the effect of growth factors of the VEGF family. Since both angiopoietins compete for the same Tie-2 receptor and cause opposite effects concerning angiogenesis, the ratio between these two ligands is crucial. Therefore, we have measured serum levels of both angiopoietins in the serum of 148 melanoma patients at different stages of disease. Whereas angiopoietin-1 levels did not change during disease progression, angiopoietin-2 levels were significantly higher in advanced stage disease. Compared to the established tumour-marker S100B, angiopoietin-2 levels or the ratio between both angiopoietins did not show increased sensitivity for the early detection of advanced stages of malignant melanoma. In conclusion, the ratio between both angiopoietins is significantly altered in late stage melanoma patients, shifting the balance to favour angiogenesis.

Stromal Fibroblast–Specific Expression of ADAM-9 Modulates Proliferation and Apoptosis in Melanoma Cells In Vitro and In Vivo

ADAMs are members of the zinc metalloproteinase superfamily characterized by the presence of disintegrin and metalloprotease domains. In human melanoma, ADAM-9 is expressed in focalized areas of the tumor-stroma border in both melanoma and stromal cells. However, the role of ADAM-9 in melanoma progression remains elusive. To analyze the role of stromal-derived ADAM-9 for the growth and survival of melanoma cells, we have used in vitro coculture systems of melanoma cells and ADAM-9(-/-) fibroblasts. Coculture of melanoma cells in the presence of ADAM-9(-/-) fibroblasts led to increased melanoma cell proliferation and reduced apoptosis as compared with control cocultures. We identified TIMP-1 and sTNFRI as the two relevant factors expressed in increased amounts in culture supernatants from ADAM-9(-/-) fibroblasts. TIMP-1 was associated with induced melanoma cell proliferation, whereas soluble TNFR1 mediated the reduced cellular apoptosis in vitro. In vivo, injection of murine melanoma cells into the flank of ADAM-9(-/-) animals resulted in the development of significantly larger tumors than in wild-type animals as a result of increased proliferation and decreased apoptosis of melanoma cells. Taken together, stromal expression of ADAM-9 during melanoma development modulates the expression of TIMP-1 and sTNFR1, which in turn affect tumor cell proliferation and apoptosis.

Oncogene and therapeutic target analyses in atypical fibroxanthomas and pleomorphic dermal sarcomas.

Background Until now, almost nothing is known about the tumorigenesis of atypical fibroxanthoma (AFX) and pleomorphic dermal sarcoma (PDS). Our hypothesis is that AFX is the non-infiltrating precursor lesion of PDS. Materials and Methods We performed the world-wide most comprehensive immunohistochemical and mutational analysis in well-defined AFX (n=5) and PDS (n=5). Results In NGS-based mutation analyses of selected regions by a 17 hotspot gene panel of 102 amplicons we could detect TP53 mutations in all PDS as well as in the only analyzed AFX and PDS of the same patient. Besides, we detected mutations in the CDKN2A, HRAS, KNSTRN and PIK3CA genes. Performing immunohistochemistry for CTNNB1, KIT, CDK4, c-MYC, CTLA-4, CCND1, EGFR, EPCAM, ERBB2, IMP3, INI-1, MKI67, MDM2, MET, p40, TP53, PD-L1 and SOX2 overexpression of TP53, CCND1 and CDK4 was seen in AFX as well as in PDS. IMP3 was upregulated in 2 AFX (weak staining) and 4 PDS (strong staining). FISH analyses for the genes FGFR1, FGFR2 and FGFR3 revealed negative results in all tumors. Conclusions UV-induced TP53 mutations as well as CCND1/CDK4 changes seem to play essential roles in tumorigenesis of PDS. Furthermore, we found some more interesting mutated genes in other oncogene pathways (activating mutations of HRAS and PIK3CA). All AFX and PDS investigated immunohistochemically presented with similar oncogene expression profiles (TP53, CCND1, CDK4 overexpression) and the single case with an AFX and PDS showed complete identical TP53 and PIK3CA mutation profiles in both tumors. This reinforces our hypothesis that AFX is the non-infiltrating precursor lesion of PDS.

Enhanced FHL2 and TGF-β1 Expression Is Associated With Invasive Growth and Poor Survival in Malignant Melanomas

OBJECTIVESnThis study examines the expression and the role of four-and-a-half LIM domains protein 2 (FHL2) and transforming growth factor β1 (TGF-β1) in human malignant melanoma. It is determined whether both proteins influence melanoma survival time.nnnMETHODSnWe analyzed the immunohistochemical staining intensities of FHL2 and TGF-β1 in normal skin and in 50 malignant melanomas with different mutation status (BRAF-V600E, NRAS codon 61 mutation, and wild type). Survival data were available for 45 cases.nnnRESULTSnIn melanocytes of nonneoplastic human skin, FHL2 expression was absent. In contrast, 38 (76%) of 50 melanomas showed strong cytoplasmic and partly nuclear FHL2 expression. At the invasion front, cytoplasmic TGF-β1 staining was observed in 32 (64%) of 50 melanomas, and a correlation of FHL2 and TGF-β1 staining intensities was detectable. In follow-up analyses, enhanced FHL2 and TGF-β1 staining intensities in the tumor invasion front were associated with poor survival.nnnCONCLUSIONSnEnhanced FHL2 and TGF-β1 expression is correlated with poor survival in human malignant melanoma. Protumorigenic effects of autocrine TGF-β1 secretion might be exerted by induction of FHL2 expression in melanoma cells. Since melanomas treated with targeted therapies often do not show sufficient response rates, inhibition of FHL2 and/or TGF-β1 might be a promising therapeutic approach.

Copy number variations in atypical fibroxanthomas and pleomorphic dermal sarcomas

Atypical fibroxanthomas (AFX) and pleomorphic dermal sarcomas (PDS) are frequent cutaneous sarcomas typically arising on sun-exposed skin in elderly patients. In contrast to AFX, which generally do not recur after complete excision, PDS locally recur in up to 50% and metastasize in up to 20%. We recently detected characteristic UV-induced TP53 mutations as potential driver mutation in almost all PDS investigated as well as activating PIK3CA and RAS gene mutations in around one third of our tumors representing targets for personalized treatments in patients with unresectable or metastasized PDS. In the present study, we identified amplifications and deletions in a small part of the PDS (6 of 27 cases) but not in AFX suggesting that copy number variations (CNV) might not be an initial event in tumor development but rather important during tumor progression. In addition to BRAF, KNSTRN, IDH1 and PDGFRA amplification, CNV analyses revealed deletions in the CDKN2A, KIT and PDGFRA genes. In cases where an appropriate FISH assay was established, the CNV results could be verified by FISH analysis. Amplification of BRAF, KIT or PDGFRA and/or losses of CDKN2A might represent bad prognostic markers, although larger studies are needed to clarify their association with prognosis or progression in PDS.

The impact of sequencing on diagnosis and treatment of malignant melanoma

ABSTRACT Melanoma is one of the clinically most important cancer types considering its high mortality rate and that it is commonly diagnosed in relatively young people. With the advent of targeted therapies and, more recently, immune checkpoint inhibitors, more treatment options are available resulting in higher patient survival rates. However, the successful application of these targeted therapies critically depends on the reliable detection of molecular aberrations. Today, massively parallel sequencing techniques enable us to analyze large sets of genes in a relatively short time. It has allowed increased knowledge of acquired somatic mutations in melanoma and has helped to identify new targets for personalized therapy, and potentially may help to predict response to immune therapies. Described here are the development of sequencing techniques, how their improvement has changed diagnosis, prognosis and management of malignant melanoma and the future perspectives of melanoma diagnostics in the routine clinical setting.