Faculty Bibliography

BACKGROUND: Melanoma patients who develop brain metastases (B-Met) have limited survival and are excluded from most clinical trials. In the current study, the authors attempted to identify primary tumor characteristics and clinical features predictive of B-Met development and post-B-Met survival. METHODS: A prospectively accrued cohort of 900 melanoma patients was studied to identify clinicopathologic features of primary melanoma (eg, thickness, ulceration, mitotic index, and lymphovascular invasion) that are predictive of B-Met development and survival after a diagnosis of B-Met. Associations between clinical variables present at the time of B-Met diagnosis (eg, extracranial metastases, B-Met location, and the presence of neurological symptoms) and post-B-Met survival were also assessed. Univariate associations were analyzed using Kaplan-Meier survival analysis, and the effect of independent predictors was assessed using multivariate Cox proportional hazards regression analysis. RESULTS: Of the 900 melanoma patients studied, 89 (10%) developed B-Met. Ulceration and site of the primary tumor on the head and neck were found to be independent predictors of B-Met development on multivariate analysis (P = .001 and P = .003, respectively). Clinical variables found to be predictive of post-B-Met survival on multivariate analysis included the presence of neurological symptoms (P = .008) and extracranial metastases (P = .04). Ulceration was the only primary tumor characteristic that remained a significant predictor of post-B-Met survival on multivariate analysis (P = .04). CONCLUSIONS: Primary tumor ulceration was found to be the strongest predictor of B-Met development and remained an independent predictor of decreased post-B-Met survival in a multivariate analysis inclusive of primary tumor characteristics and clinical variables. The results of the current study suggest that patients with ulcerated primary tumors should be prospectively studied to determine whether heightened surveillance for B-Met can improve clinical outcome. Cancer 2011. (c) 2010 American Cancer Society

Superficial spreading melanoma (SSM) and nodular melanoma (NM) are believed to represent sequential phases of linear progression from radial to vertical growth. Several lines of clinical, pathological and epidemiologic evidence suggest, however, that SSM and NM might be the result of independent pathways of tumor development. We utilized an integrative genomic approach that combines single nucleotide polymorphism array (SNP 6.0, Affymetrix) with gene expression array (U133A 2.0, Affymetrix) to examine molecular differences between SSM and NM. Pathway analysis of the most differentially expressed genes between SSM and NM (N=114) revealed significant differences related to metabolic processes. We identified 8 genes (DIS3, FGFR1OP, G3BP2, GALNT7, MTAP, SEC23IP, USO1, ZNF668) in which NM/SSM-specific copy number alterations correlated with differential gene expression (P<0.05, Spearman's rank). SSM-specific genomic deletions in G3BP2, MTAP, and SEC23IP were independently verified in two external data sets. Forced overexpression of metabolism-related gene methylthioadenosine phosphorylase (MTAP) in SSM resulted in reduced cell growth. The differential expression of another metabolic related gene, aldehyde dehydrogenase 7A1 (ALDH7A1), was validated at the protein level using tissue microarrays of human melanoma. In addition, we show that the decreased ALDH7A1 expression in SSM may be the result of epigenetic modifications. Our data reveal recurrent genomic deletions in SSM not present in NM, which challenge the linear model of melanoma progression. Furthermore, our data suggest a role for altered regulation of metabolism-related genes as a possible cause of the different clinical behavior of SSM and NM

In this study, we investigated the mechanism(s) of altered expression of protooncogene SKP2 in metastatic melanoma and its clinical relevance in patients with metastatic melanoma. The genomic status of SKP2 was assessed in cell lines by sequencing, single nucleotide polymorphism array, and genomic PCR. Copy number status was then evaluated for concordance with SKP2 mRNA and protein expression. SKP2 protein was further evaluated by immunohistochemistry in 93 human metastatic tissues. No mutations were identified in SKP2. Increased copy number at the SKP2 locus was observed in 6/14 (43%) metastatic cell lines and in 9/22 (41%) human metastatic tissues which was associated with overexpression of SKP2 protein. Overexpression of SKP2 protein in human tissues was associated with worse survival in a multivariate model controlling for the site of metastasis. Copy number gain is a major contributing mechanism of SKP2 overexpression in metastatic melanoma. Results may have implications for the development of therapeutics that target SKP2

Objective: Previous melanoma studies evaluating prognostic factors of survival at recurrence have focused on primary tumor characteristics and clinical variables at first recurrence. We examined the prognostic relevance of recurrent tumor proliferation. Methods: 114 melanoma patients with available recurrent tissues who were prospectively enrolled at New York University Medical Center were studied. Standard of care prognostic variables (e.g. stage at initial diagnosis and lactate dehydrogenase level) and recurrent tissue expression of proliferative marker Ki-67 were evaluated for their association with overall survival. Results: High Ki-67 expression was observed in 57 (50%) of the 114 recurrent melanomas. On univariate analysis, the median overall survival of patients whose recurrent tumors overexpressed Ki-67 was significantly shorter than that of patients whose recurrent tumors had low Ki-67 expression (3.6 vs. 9.5 years, p = 0.03). On multivariate analysis, a high proliferative index of the recurrent melanoma remained an independent predictor of worse overall survival, controlling for stage at initial diagnosis, disease-free survival, and stage at first recurrence [HR = 2.09 (95% CI 1.24-3.54), p = 0.006]. Conclusions: Our results demonstrate the prognostic relevance of tumor proliferation in recurrent melanoma patients. Data also support restratification of risk assessment upon recurrence that considers tumor biology in addition to clinical variables evaluated as part of the standard of care

Background: Although the current median survival time of stage-IV melanoma patients is less than 12 months, there is a subset of patients who experience long-term survival. Due to poor response rates to standard cytotoxic agents in metastatic melanoma, patients are encouraged to participate in clinical trials, the overall impact of which has not been studied, however. The aim of our study was to identify the factors associated with long-term survival and to determine the impact of clinical trial enrollment on patient outcome. Methods: We studied stage-IV melanoma patients prospectively enrolled at New York University Medical Center from 2002-2008. Associations between clinicopathologic variables and overall post-stage-IV survival were examined. Kaplan-Meier survival analysis was used to identify univariate predictors of post-stage-IV survival and the independent effect of these variables was assessed in a multivariate Cox proportional hazards regression model. The associations between clinicopathologic variables and long-term survival status (>/=2 vs. <2 years) were examined by chi(2) analysis and the independent effect of these variables on the latter was assessed in a multivariate logistic regression model. Results: Site of metastasis, treatment (systemic vs. localized) and pretreatment lactate dehydrogenase (LDH) level independently correlated with post-stage-IV survival. Participation in clinical trials and normal LDH levels were associated with a long-term survival of >/=2 years. Conclusion: Our data suggest that enrollment in clinical trials independently correlates with prolonged survival after a diagnosis of stage IV melanoma.

[This corrects the article on p. e25264 in vol. 6.]

Several reports have demonstrated a role for aberrant NOTCH signaling in melanoma genesis and progression, prompting us to explore if targeting this pathway is a valid therapeutic approach against melanoma. We targeted NOTCH signaling using RO4929097, a novel inhibitor of gamma secretase, which is a key component of the enzymatic complex that cleaves and activates NOTCH. The effects of RO4929097 on the oncogenic and stem cell properties of a panel of melanoma cell lines were tested both in vitro and in vivo, using xenograft models. In human primary melanoma cell lines, RO4929097 decreased the levels of NOTCH transcriptional target HES1. This was accompanied by reduced proliferation and impaired ability to form colonies in soft agar and to organize in tridimensional spheres. Moreover, RO4929097 affected the growth of human primary melanoma xenograft in NOD/SCID/IL2gammaR-/- mice and inhibited subsequent tumor formation in a serial xenotransplantation model, suggesting that inhibition of NOTCH signaling suppresses the tumor initiating potential of melanoma cells. In addition, RO4929097 decreased tumor volume and blocked the invasive growth pattern of metastatic melanoma cell lines in vivo. Finally, increased gene expression of NOTCH signaling components correlated with shorter post recurrence survival in metastatic melanoma cases. Our data support NOTCH inhibition as a promising therapeutic strategy against melanoma

BACKGROUND: Sorafenib monotherapy in patients with metastatic melanoma was explored in this multi-institutional phase II study. In correlative studies the impact of sorafenib on cyclin D1 and Ki67 was assessed. METHODOLOGY/PRINCIPAL FINDINGS: Thirty-six patients treatment-naive advanced melanoma patients received sorafenib 400 mg p.o. twice daily continuously. Tumor BRAF(V600E) mutational status was determined by routine DNA sequencing and mutation-specific PCR (MSPCR). Immunohistochemistry (IHC) staining for cyclin D1 and Ki67 was performed on available pre- and post treatment tumor samples. The main toxicities included diarrhea, alopecia, rash, mucositis, nausea, hand-foot syndrome, and intestinal perforation. One patient had a RECIST partial response (PR) lasting 175 days. Three patients experienced stable disease (SD) with a mean duration of 37 weeks. Routine BRAF(V600E) sequencing yielded 27 wild-type (wt) and 6 mutant tumors, whereas MSPCR identified 12 wt and 18 mutant tumors. No correlation was seen between BRAF(V600E) mutational status and clinical activity. No significant changes in expression of cyclin D1 or Ki67 with sorafenib treatment were demonstrable in the 15 patients with pre-and post-treatment tumor samples. CONCLUSIONS/SIGNIFICANCE: Sorafenib monotherapy has limited activity in advanced melanoma patients. BRAF(V600E) mutational status of the tumor was not associated with clinical activity and no significant effect of sorafenib on cyclin D1 or Ki67 was seen, suggesting that sorafenib is not an effective BRAF inhibitor or that additional signaling pathways are equally important in the patients who benefit from sorafenib. TRIAL REGISTRATION: Clinical Trials.gov NCT00119249

The incidence of melanoma has increased 3-7% per year, and is now approaching 30 per 100,000 individuals. This rate is faster than any other cancer, and is predicted to double every 10-20 years [1]. Surgery can be curative in Stage I, II, or III disease, but 75% of patients with deep primary lesions will develop extensive recurrence or distant metastases (Stage IV disease). To date, no curative treatment exists for Stage IV melanoma and these patients have a median overall survival of only 7 months [2]. A subset of patients can be salvaged with surgical resection of metastatic sites, but no adjuvant therapy has further improved the outcome [3]. The only FDA approved adjuvant therapy for Stage IV melanoma is alpha-interferon. Several trials have demonstrated an increase in relapse-free survival; however, toxicity is high and overall survival remains controversial. Several reports have demonstrated a role for aberrant Notch signaling in melanoma genesis or progression, prompting us to explore if targeting this pathway is a valid therapeutic approach against melanoma. To investigate the potential benefits of Notch inhibition in melanoma, we are using RO4929097, a novel inhibitor of gamma secretase, a key component of the enzymatic complex that cleaves and activates Notch. RO4929097 is completing Phase I dose escalation in cancer patients and a CTEP-sponsored Phase II clinical trial in melanoma is currently under review. We have generated DNA microarray data for a series of 22 melanoma cell lines at both the gene expression and DNA copy number level. Preliminary gene expression analysis has indicated that melanoma cells over express crucial components of NOTCH-pathway, such as Hey1 Hey2 and NOXA. Furthermore, integration of gene expression and copy number data for NOTCH2 suggests that the increased DNA copy number play a role in the increase in gene expression. We have also tested the efficacy of RO4929047 in human melanoma cell lines. We have observed that treatment with RO4929097 for 24h causes a!