Erica B. Friedman

Serum microRNAs as biomarkers for recurrence in melanoma

BackgroundIdentification of melanoma patients at high risk for recurrence and monitoring for recurrence are critical for informed management decisions. We hypothesized that serum microRNAs (miRNAs) could provide prognostic information at the time of diagnosis unaccounted for by the current staging system and could be useful in detecting recurrence after resection.MethodsWe screened 355 miRNAs in sera from 80 melanoma patients at primary diagnosis (discovery cohort) using a unique quantitative reverse transcription-PCR (qRT-PCR) panel. Cox proportional hazard models and Kaplan-Meier recurrence-free survival (RFS) curves were used to identify a miRNA signature with prognostic potential adjusting for stage. We then tested the miRNA signature in an independent cohort of 50 primary melanoma patients (validation cohort). Logistic regression analysis was performed to determine if the miRNA signature can determine risk of recurrence in both cohorts. Selected miRNAs were measured longitudinally in subsets of patients pre-/post-operatively and pre-/post-recurrence.ResultsA signature of 5 miRNAs successfully classified melanoma patients into high and low recurrence risk groups with significant separation of RFS in both discovery and validation cohorts (p = 0.0036, p = 0.0093, respectively). Significant separation of RFS was maintained when a logistic model containing the same signature set was used to predict recurrence risk in both discovery and validation cohorts (p < 0.0001, p = 0.033, respectively). Longitudinal expression of 4 miRNAs in a subset of patients was dynamic, suggesting miRNAs can be associated with tumor burden.ConclusionOur data demonstrate that serum miRNAs can improve accuracy in identifying primary melanoma patients with high recurrence risk and in monitoring melanoma tumor burden over time.

Immune response in melanoma: an in-depth analysis of the primary tumor and corresponding sentinel lymph node.

The sentinel lymph node is the initial site of metastasis. Downregulation of antitumor immunity has a role in nodal progression. Our objective was to investigate the relationship between immune modulation and sentinel lymph node positivity, correlating it with outcome in melanoma patients. Lymph node/primary tissues from melanoma patients prospectively accrued and followed at New York University Medical Center were evaluated for the presence of regulatory T cells (Foxp3+) and dendritic cells (conventional: CD11c+, mature: CD86+) using immunohistochemistry. Primary melanoma immune cell profiles from sentinel lymph node-positive/-negative patients were compared. Logistic regression models inclusive of standard-of-care/immunological primary tumor characteristics were constructed to predict the risk of sentinel lymph node positivity. Immunological responses in the positive sentinel lymph node were also compared with those in the negative non-sentinel node from the same nodal basin and matched negative sentinel lymph node. Decreased immune response was defined as increased regulatory T cells or decreased dendritic cells. Associations between the expression of these immune modulators, clinicopathological variables, and clinical outcome were evaluated using univariate/multivariate analyses. Primary tumor conventional dendritic cells and regression were protective against sentinel lymph node metastasis (odds ratio=0.714, 0.067; P=0.0099, 0.0816, respectively). Antitumor immunity was downregulated in the positive sentinel lymph node with an increase in regulatory T cells compared with the negative non-sentinel node from the same nodal basin (P=0.0005) and matched negative sentinel lymph node (P=0.0002). The positive sentinel lymph node also had decreased numbers of conventional dendritic cells compared with the negative sentinel lymph node (P<0.0001). Adding sentinel lymph node regulatory T cell expression improved the discriminative power of a recurrence risk assessment model using clinical stage. Primary tumor regression was associated with prolonged disease-free (P=0.025) and melanoma-specific (P=0.014) survival. Our results support an assessment of local immune profiles in both the primary tumor and sentinel lymph node to help guide therapeutic decisions.

Superficial spreading and nodular melanoma are distinct biological entities: a challenge to the linear progression model

The classification of melanoma subtypes into prognostically relevant and therapeutically insightful categories has been a challenge since the first description of melanoma in the 1800s. One limitation has been the assumption that the two most common histological subtypes of melanoma, superficial spreading and nodular, evolve according to a linear model of progression, as malignant melanocytes spread radially and then invade vertically. However, recent clinical, pathological, and molecular data indicate that these two histological subtypes might evolve as distinct entities. Here, we review the published data that support distinct molecular characterization of superficial spreading and nodular melanoma, the clinical significance of this distinction including prognostic relevance and the therapeutic implications.

Hedgehog pathway blockade inhibits melanoma cell growth in vitro and in vivo.

Previous reports have demonstrated a role for hedgehog signaling in melanoma progression, prompting us to explore the therapeutic benefit of targeting this pathway in melanoma. We profiled a panel of human melanoma cell lines and control melanocytes for altered expression of hedgehog pathway members and determined the consequences of both genetic and pharmacological inhibition of the hedgehog pathway activator Smoothened (SMO) in melanoma, both in vitro and in vivo. We also examined the relationship between altered expression of hedgehog pathway mediators and survival in a well-characterized cohort of metastatic melanoma patients with prospectively collected follow up information. Studies revealed that over 40% of the melanoma cell lines examined harbored significantly elevated levels of the hedgehog pathway mediators SMO, GLI2, and PTCH1 compared to melanocytes (p < 0.05). SMO inhibition using siRNA and the small molecule inhibitor, NVP-LDE-225, suppressed melanoma growth in vitro, particularly in those cell lines with moderate SMO and GLI2 expression. NVP-LDE-225 also induced apoptosis in vitro and inhibited melanoma growth in a xenograft model. Gene expression data also revealed evidence of compensatory up-regulation of two other developmental pathways, Notch and WNT, in response to hedgehog pathway inhibition. Pharmacological and genetic SMO inhibition also downregulated genes involved in human embryonic stem cell pluripotency. Finally, increased SMO expression and decreased expression of the hedgehog pathway repressor GLI3 correlated with shorter post recurrence survival in metastatic melanoma patients. Our data demonstrate that hedgehog pathway inhibition might be a promising targeted therapy in appropriately selected metastatic melanoma patients.

Melanoma expression of matrix metalloproteinase-23 is associated with blunted tumor immunity and poor responses to immunotherapy

BackgroundMatrix metalloproteinase-23 (MMP-23) can block the voltage-gated potassium channel Kv1.3, whose function is important for sustained Ca2+ signaling during T cell activation. MMP-23 may also alter T cell activity and phenotype through cleavage of proteins affecting cytokine and chemokine signaling. We therefore tested the hypothesis that MMP-23 can negatively regulate the anti-tumor T cell response in human melanoma.MethodsWe characterized MMP-23 expression in primary melanoma patients who received adjuvant immunotherapy. We examined the association of MMP-23 with the anti-tumor immune response - as assessed by the prevalence of tumor-infiltrating lymphocytes and Foxp3+ regulatory T cells. Further, we examined the association between MMP-23 expression and response to immunotherapy. Considering also an in trans mechanism, we examined the association of melanoma MMP-23 and melanoma Kv1.3 expression.ResultsOur data revealed an inverse association between primary melanoma MMP-23 expression and the anti-tumor T cell response, as demonstrated by decreased tumor-infiltrating lymphocytes (TIL) (P = 0.05), in particular brisk TILs (P = 0.04), and a trend towards an increased proportion of immunosuppressive Foxp3+ regulatory T cells (P = 0.07). High melanoma MMP-23 expression is also associated with recurrence in patients treated with immune biologics (P = 0.037) but not in those treated with vaccines (P = 0.64). Further, high melanoma MMP-23 expression is associated with shorter periods of progression-free survival for patients receiving immune biologics (P = 0.025). On the other hand, there is no relationship between melanoma MMP-23 and melanoma Kv1.3 expression (P = 0.27).ConclusionsOur data support a role for MMP-23 as a potential immunosuppressive target in melanoma, as well as a possible biomarker for informing melanoma immunotherapies.

Screening prior to Breast Cancer Diagnosis: The More Things Change, the More They Stay the Same

Purpose. In November 2009, the U.S. Preventative Service Task Force (USPSTF) revised their breast cancer screening guidelines. We evaluated the pattern of screening subsequent to the altered guidelines in a cohort of women. Methods. Our database was queried for the following variables: age, race, method of diagnosis, mass palpability, screening frequency, histology, and stage. Statistical analyses were performed using Pearsons chi-square and Fishers exact tests. Results. 1112 women were diagnosed with breast cancer from January 2010 to 2012. The median age at diagnosis was 60 years. Most cancers were detected on mammography (61%). The majority of patients had invasive ductal carcinoma (59%), stage 0 (23%), and stage 1 (50%) cancers. The frequency of screening did not change significantly over time (P = 0.30). However, nonregular screeners had an increased risk of being diagnosed with later stage breast cancer (P < 0.001) and were more likely to present with a palpable mass compared to regular screeners (56% versus 21%; P < 0.001). Conclusions. In our study, screening behavior did not significantly change in the years following the USPSTF guidelines. These results suggest that women who are not screened annually are at increased risk of a delay in breast cancer diagnosis, which may impact treatment options and outcomes.

The breast cancer lifestyle intervention study.

112 Background: Maintaining a healthy weight after breast cancer diagnosis has been associated with improved survival outcomes. Lifestyle interventions are particularly important in overweight women who are at an increased risk of overall and breast-cancer specific death compared to non-overweight women. The purpose of this study is to examine the barriers and acceptance of a lifestyle intervention program among overweight women with newly diagnosed breast cancer. METHODS The Breast Cancer Database of NYU Langone Medical Center was queried for women who were newly diagnosed with breast cancer and who had a body mass index (BMI) ≥25kg/m2. Eligible patients participated in the Moving for Life (MFL) exercise program for 16 sessions. Questionnaires were administered at baseline and at the end of the intervention. Descriptive statistics were used to summarize patient characteristics and paired t-tests were used to see if there were any significant differences before and after the intervention. RESULTS A total of 40 women were eligible to participate in the MFL exercise program. A total of 20 women declined to participate due to location, transportation limitations, and conflicts in schedule. Of the 18 women who enrolled in the MFL program, 13 (72%) were regular attendees and completed the study. The median age was 61 years (range: 38-76) and the average baseline BMI was 31kg/m2(range: 25-42). After completing the MFL intervention, there was a significant decrease in weight and BMI (p=0.04). The average weight loss was 10lbs. Participants also reported a greater enjoyment of exercise (p=0.02), as well as a decrease in pain related to treatment (p=0.05). CONCLUSIONS Moving for Life is a unique exercise program for breast cancer patients and had a high rate of acceptance and completion in a cohort of overweight breast cancer patients. This study resulted in a statistically significant average weight loss of 10lbs, as well as a greater enjoyment of exercise and decrease in treatment-related pain which may impact long-term lifestyle changes. Longitudinal follow-up at 6- and 12-months will allow assessment of secondary endpoints, including exercise frequency and attitudes about exercise, allowing us to examine sustainability and changes in behaviors and attitudes over time.

Abstract 425: Targeting embryonic signaling pathways in melanoma

Proceedings: AACR 103rd Annual Meeting 2012‐‐ Mar 31‐Apr 4, 2012; Chicago, IL Melanoma incidence is quickly rising and the average survival for a patient with metastatic disease is less than one year. Novel targeted therapies, such as B-Raf mutant kinase inhibitors, have shown dramatic initial responses, but resistance to single agent therapy inevitably ensues. We hypothesize that melanoma stem-like cells may be important in melanoma progression and may play a role in chemoresistance to targeted therapy. We have profiled melanoma cell lines as well as metastatic melanoma tissue for activation of embryonic stem cell pathways via microarray and quantitative RT-PCR. We observed upregulation of the Hedgehog pathway in a subset of cell lines and in human melanoma tissue and found that Smoothened (SMO) expression was associated with significantly shorter recurrence-free survival in metastatic melanoma patients. We also found that small molecule inhibition or genetic silencing of Smoothened (SMO) decreased melanoma cell proliferation and migration in vitro and identified overexpression of GLI2 as a marker of resistance to SMO inhibition. These findings suggest that inhibitors of hedgehog pathway signaling, already in clinical trials in other tumor types, may be a novel strategy for advanced melanoma. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 425. doi:1538-7445.AM2012-425