Melanoma Brain Metastases in the Era of Target Therapies: An Overview.

Malignant melanoma is the third most common type of tumor that causes brain metastases. Patients with cerebral involvement have a dismal prognosis and their treatment is an unmet medical need. Brain involvement is a multistep process involving several signaling pathways such as Janus kinase/signal Transducer and Activator of Transcription (JAK/STAT), Phosphoinositide 3-kinase/Protein Kinase B (PI3K/AKT), Vascular Endothelial Growth Factor and Phosphatase and Tensin Homolog (PTEN). Recently therapy that targets the MAPK signaling (BRAF/MEK inhibitors) and immunotherapy (anti-CTLA4 and anti-PD1 agents) have changed the therapeutic approaches to stage IV melanoma. In contrast, there are no solid data about patients with brain metastases, who are usually excluded from clinical trials. Retrospective data showed that BRAF-inhibitors, alone or in combination with MEK-inhibitors have interesting clinical activity in this setting. Prospective data about the combinations of BRAF/MEK inhibitors have been recently published, showing an improved overall response rate. Short intracranial disease control is still a challenge. Several attempts have been made in order to improve it with combinations between local and systemic therapies. Immunotherapy approaches seem to retain promising activity in the treatment of melanoma brain metastasis as showed by the results of clinical trials investigating the combination of anti-CTL4 (Ipilimumab) and anti-PD1(Nivolumab). Studies about the combination or the sequential approach of target therapy and immunotherapy are ongoing, with immature results. Several clinical trials are ongoing trying to explore new approaches in order to overcome tumor resistance. At this moment the correct therapeutic choices for melanoma with intracranial involvement is still a challenge and new strategies are needed.

BRAF-inhibitors can exert control of disease in BRAF T599I mutated melanoma: a case report.

BRAF signaling is involved in melanoma growth in more than half of metastatic patients. In the last few years, new drugs that block this pathway have significantly improved the outcomes of patients with metastatic melanoma. Ninety percent of BRAF mutations involve exon 15, and the most frequent, V600E, results from the amino acid change from valine (V) to glutamic acid (E). BRAF inhibitor treatments have shown a notable overall response rate and improvements in progression-free and overall survival. Rare BRAF mutations of codon 599 have been also described in a few patients with papillary thyroid cancer and melanoma. Nowadays, no evidence is available in the literature, describing the role of target therapies as treatment in patients with this specific codon mutation. We describe the case of a young woman with metastatic melanoma with a particular BRAF mutation, T599I, who has benefited from treatment with a BRAF inhibitor, vemurafenib.

Cytokine-Induced Killer Cells Kill Chemo-surviving Melanoma Cancer Stem Cells.

Purpose: The MHC-unrestricted activity of cytokine-induced killer (CIK) cells against chemo-surviving melanoma cancer stem cells (mCSC) was explored, as CSCs are considered responsible for chemoresistance and relapses.Experimental Design: Putative mCSCs were visualized by engineering patient-derived melanoma cells (MC) with a lentiviral vector encoding eGFP under expression control by stemness gene promoter oct4 Their stemness potential was confirmed in vivo by limiting dilution assays. We explored the sensitivity of eGFP+ mCSCs to chemotherapy (CHT), BRAF inhibitor (BRAFi) or CIK cells, as single agents or in sequence, in vitro First, we treated MCs in vitro with fotemustine or dabrafenib (BRAF-mutated cases); then, surviving MCs, enriched in mCSCs, were challenged with autologous CIK cells. CIK cell activity against chemoresistant mCSCs was confirmed in vivo in two distinct immunodeficient murine models.Results: We visualized eGFP+ mCSCs (14% ± 2.1%) in 11 MCs. The tumorigenic precursor rate in vivo was higher within eGFP+ MCs (1/42) compared with the eGFP- counterpart (1/4,870). In vitro mCSCs were relatively resistant to CHT and BRAFi, but killed by CIK cells (n = 11, 8/11 autologous), with specific lysis ranging from 95% [effector:tumor ratio (E:T), 40:1] to 20% (E:T 1:3). In vivo infusion of autologous CIK cells into mice bearing xenografts from three distinct melanomas demonstrated significant tumor responses involving CHT-spared eGFP+ mCSCs (P = 0.001). Sequential CHT-immunotherapy treatment retained antitumor activity (n = 12, P = 0.001) reducing mCSC rates (P = 0.01).Conclusions: These findings are the first demonstration that immunotherapy with CIK cells is active against autologous mCSCs surviving CHT or BRAFi. An experimental platform for mCSC study and rationale for CIK cells in melanoma clinical study is provided. Clin Cancer Res; 23(9); 2277-88. ©2016 AACR.

Clear cell sarcoma (malignant melanoma of soft parts) and sentinel lymph node biopsy.

Clear cell sarcoma of the tendons and aponeuroses is an aggressive, rare soft tissue tumour that occurs predominantly in the extremities of young adults. Although it appears to be histogenetically related to melanoma, its clinical behaviour resembles soft tissue sarcoma. Prognosis is reported to be poor due to the great propensity of regional and distant metastases. The risk of metastases to regional lymph nodes is very high. We describe a case of clear cell sarcoma of the hand and evaluate the feasibility of the sentinel lymph node biopsy (SLNB) technique in this kind of tumour. Up to now, there are no reports that describe the use of SLNB in clear cell sarcoma. The SLNB technique was carried out with success and the sentinel lymphnode was easily identified. Histological examination of the lymphnode allowed identification of metastatic cells and thus provide for radical lymphadenectomy. We maintain that SLNB can be successfully used for this type of tumour although this result should be evaluated and confirmed by larger case studies.

Anti-tumor necrosis factor alpha monoclonal antibody (infliximab) for the treatment of Pyoderma gangrenosum associated with Crohn's disease.

Here we report a case of Pyoderma gangrenosum (PG) associated with Crohn's disease successfully treated with infliximab. The efficacy of this drug in many inflammatory diseases has already been reported, but its use in PG has only been seen in very few cases. Our study confirms that this therapy is a valid alternative solution for treating PG, which is often unresponsive to conventional therapies.

Effective activity of cytokine-induced killer cells against autologous metastatic melanoma including cells with stemness features.

PURPOSE: We investigate the unknown tumor-killing activity of cytokine-induced killer (CIK) cells against autologous metastatic melanoma and the elusive subset of putative cancer stem cells (mCSC). EXPERIMENTAL DESIGN: We developed a preclinical autologous model using same patient-generated CIK cells and tumor targets to consider the unique biology of each patient/tumor pairing. In primary tumor cell cultures, we visualized and immunophenotypically defined a putative mCSC subset using a novel gene transfer strategy that exploited their exclusive ability to activate the promoter of stemness gene Oct4. RESULTS: The CIK cells from 10 patients with metastatic melanoma were successfully expanded (median, 23-fold; range, 11-117). Primary tumor cell cultures established and characterized from the same patients were used as autologous targets. Patient-derived CIK cells efficiently killed autologous metastatic melanoma [up to 71% specific killing (n = 26)]. CIK cells were active in vivo against autologous melanoma, resulting in delayed tumor growth, increased necrotic areas, and lymphocyte infiltration at tumor sites. The metastatic melanoma cultures presented an average of 11.5% ± 2.5% putative mCSCs, which was assessed by Oct4 promoter activity and stemness marker expression (Oct4, ABCG2, ALDH, MITF). Expression was confirmed on mCSC target molecules recognized by CIK cells (MIC A/B; ULBPs). CIK tumor killing activity against mCSCs was intense (up to 71%, n = 4) and comparable with results reported against differentiated metastatic melanoma cells (P = 0.8). CONCLUSIONS: For the first time, the intense killing activity of CIK cells against autologous metastatic melanoma, including mCSCs, has been shown. These findings move clinical investigation of a new immunotherapy for metastatic melanoma, including mCSCs, closer.

In melanocytic lesions the fraction of BRAF V600E alleles is associated with sun exposure but unrelated to ERK phosphorylation.

BRAF(V600E) mutation has been frequently reported in different types of melanocytic lesions, but its role in melanomagenesis is poorly understood, having been associated with either the proliferative-induced MAPK pathway activation or the acquisition of oncogene-driven senescence. The presence of BRAF alterations has been related to sun exposure, although the molecular mechanisms underlying this event are only partly known. To elucidate the relationships among BRAF/NRAS alterations, MAPK pathway activation, and sun exposure, we examined 22 acquired nevi and 18 cutaneus melanomas from 38 patients. Microdissected tissues from each lesion were subjected to BRAF/NRAS mutation analysis by sequencing, allele-specific PCR and pyrosequencing assay. The same lesions were also examined for the expression of phosphorylated ERK1/2. Phototype and an accurate history of sun exposure were evaluated for each patient. BRAF(V600E) mutation was detected in 50% of the acquired nevi and in 70% of the cutaneus melanomas in the absence of NRAS alterations. The fraction of alleles carrying BRAF(V600E) substitution was variable but strongly associated with sun exposure. In contrast, no relationship was evidenced between the presence of this mutation and patients' phototype, phosphorylated ERK1/2 expression, or Clark's level. Our findings indicate that in melanocytic lesions, BRAF(V600E) mutation can affect a subset of the cells and is associated with the type and quantity of sun exposure. This mutation is independent of the nevo-melanoma progression and unrelated to ERK phosphorylation, suggesting that alternative mechanisms to the MAPK activation are also involved in this type of transformation.