[Immunotherapy for malignant melanoma]. / Immuntherapie beim malignen Melanom.

Although cutaneous melanoma accounts for only about 4% of all skin cancers (including nonmelanocytic skin cancer), it is responsible for 80% of all deaths caused by skin cancer. The introduction of immune checkpoint inhibitors led to a significant improvement in long-term survival of patients in an advanced stage regardless of BRAF mutation status. In addition to targeted therapy for patients with BRAF-mutated melanoma, immunotherapies are the therapies of choice in advanced stages and, since 2018, also in the adjuvant setting. The effectiveness of combination therapies and sequences of targeted and immunotherapies are currently being tested.

Altered endosomal-lysosomal biogenesis in melanoma.

Cutaneous melanoma is the deadliest form of skin neoplasm and its high mortality rates could be averted by early accurate detection. While the detection of melanoma is currently reliant upon melanin visualisation, research into melanosome biogenesis, as a key driver of pathogenesis, has not yielded technology that can reliably distinguish between atypical benign, amelanotic and melanotic lesions. The endosomal-lysosomal system has important regulatory roles in cancer cell biology, including a specific functional role in melanosome biogenesis. Herein, the involvement of the endosomal-lysosomal system in melanoma was examined by pooled secondary analysis of existing gene expression datasets. A set of differentially expressed endosomal-lysosomal genes was identified in melanoma, which were interconnected by biological function. To illustrate the protein expression of the dysregulated genes, immunohistochemistry was performed on samples from patients with cutaneous melanoma to reveal candidate markers. This study demonstrated the dysregulation of Syntenin-1, Sortilin and Rab25 may provide a differentiating feature between cutaneous melanoma and squamous cell carcinoma, while IGF2R may indicate malignant propensity in these skin cancers.

Multiple Molecular Pathways in Melanomagenesis: Characterization of Therapeutic Targets.

Molecular mechanisms involved in pathogenesis of malignant melanoma have been widely studied and novel therapeutic treatments developed in recent past years. Molecular targets for therapy have mostly been recognized in the RAS-RAF-MEK-ERK and PI3K-AKT signaling pathways; small-molecule inhibitors were drawn to specifically target key kinases. Unfortunately, these targeted drugs may display intrinsic or acquired resistance and various evidences suggest that inhibition of a single effector of the signal transduction cascades involved in melanoma pathogenesis may be ineffective in blocking the tumor growth. In this sense, a wider comprehension of the multiple molecular alterations accounting for either response or resistance to treatments with targeted inhibitors may be helpful in assessing, which is the most effective combination of such therapies. In the present review, we summarize the known molecular mechanisms underlying either intrinsic and acquired drug resistance either alternative roads to melanoma pathogenesis, which may become targets for innovative anticancer approaches.