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Background: Blood molecular profiling of circulating tumor cells (CTCs) can enable monitoring of patients with metastatic melanoma during checkpoint inhibitor immunotherapy (CII) and in combination with targeted therapies. We developed a microfluidics-based CTC platform to explore CTC profiling utility in CII-treated patients with melanoma using a melanoma messenger RNA (mRNA)/DNA biomarker panel., Methods: Blood samples (n = 213) were collected prospectively from 75 American Joint Committee on Cancer-staged III/IV melanoma patients during CII treatment and those enriched for CTCs. CTC profiling was performed using 5 known melanoma mRNA biomarkers and BRAF V600E DNA mutation. CTC biomarker status associations with clinical outcomes were assessed., Results: CTCs were detected in 88% of blood samples from patients with melanoma. CTC-derived biomarkers and clinical variables analyzed using classification and regression tree analysis revealed that a combination of lactate dehydrogenase, CTC-mRNA biomarkers, and tumor BRAF-mutation status was indicative of clinical outcomes for patients with stage IV melanoma (n = 52). The panel stratified low-risk and high-risk patients, whereby the latter had poor disease-free (P = 0.03) and overall survival (P = 0.02). Incorporation of a DNA biomarker with mRNA profiling increased overall CTC-detection capability by 57% compared to mRNA profiling only. RNA sequencing of isolated CTCs identified significant catenin beta 1 (CTNNB1) overexpression (P <0.01) compared to nondisease donor blood. CTC-CTNNB1 was associated with progressive disease/stable disease compared to complete-responder patient status (P = 0.02). Serial CTC profiling identified subclinical disease in patients who developed progressive disease during treatment/follow-up., Conclusions: CTC-derived mRNA/DNA biomarkers have utility for monitoring CII, targeted, and combinatorial therapies in metastatic melanoma patients., (© 2019 American Association for Clinical Chemistry.) more...

Purpose: Abnormal activation of the NF-κB pathway induces a more aggressive phenotype of cutaneous melanoma. Understanding the mechanisms involved in melanoma NF-κB activation may identify novel targets for this pathway. KPC1, an E3 ubiquitin ligase, is a regulator of the NF-κB pathway. The objective of this study was to investigate the mechanisms regulating KPC1 expression and its clinical impact in melanoma. Experimental Design: The clinical impact of KPC1 expression and its epigenetic regulation were assessed in large cohorts of clinically well-annotated melanoma tissues (tissue microarrays; n = 137, JWCI cohort; n = 40) and The Cancer Genome Atlas database (TCGA cohort, n = 370). Using melanoma cell lines, we investigated the functional interactions between KPC1 and NF-κB, and the epigenetic regulations of KPC1, including DNA methylation and miRNA expression. Results: We verified that KPC1 suppresses melanoma proliferation by processing NF-κB1 p105 into p50, thereby modulating NF-κB target gene expression. Concordantly, KPC1 expression was downregulated in American Joint Committee on Cancer stage IV melanoma compared with early stages (stage I/II P = 0.013, stage III P = 0.004), and low KPC1 expression was significantly associated with poor overall survival in stage IV melanoma ( n = 137; HR 1.810; P = 0.006). Furthermore, our data showed that high miR-155-5p expression, which is controlled by DNA methylation at its promoter region (TCGA; Pearson's r -0.455; P < 0.001), is significantly associated with KPC1 downregulation (JWCI; P = 0.028, TCGA; P = 0.003). Conclusions: This study revealed novel epigenetic regulation of KPC1 associated with NF-κB pathway activation, promoting metastatic melanoma progression. These findings suggest the potential utility of KPC1 and its epigenetic regulation as theranostic targets. Clin Cancer Res; 23(16); 4831-42. ©2017 AACR ., (©2017 American Association for Cancer Research.) more...

Circulating cell-free(cf) microRNAs (miRNAs) have been reported to exist in plasma. MicroRNA-210(miR-210) is known to play important roles in the tumor hypoxic state. We hypothesized that the expression levels of cf-miR-210 in plasma would predict early clinical recurrence in melanoma patients. A direct miRNA assay on plasma (RT-qPCR-DP) was developed to improve cf-miRNA assay logistics, eliminate RNA extraction, and reduce specimen amount required. RNA was extracted from formalin-fixed paraffin-embedded (FFPE) melanoma tissues (n = 108) and assessed by RT-qPCR. Plasma (10 μl; n = 264) was procured from AJCC Stage III/IV patients in phase III clinical trials. A RT-qPCR-DP was performed to detect cf-miR-210. MiR-210 was significantly higher in metastatic tumors compared to primary tumors. Cf-miR-210 was significantly higher in melanoma patients versus healthy donor controls. In serial bloods within individual patients, cf-miR-210 < 3 months prior to disease recurrence significantly increased compared to baseline levels (p = 0.012). ROC curve analysis demonstrated that patients with elevated cf-miR-210 were more likely to have disease recurrence. Moreover, cf-miR-210 increase significantly correlated with poorer prognosis (p < 0.001). Lactate dehydrogenase (LDH) level was also assessed within patients, and the AIC values for proportional hazards regression models of cf-miR-210(120.01) and LDH (122.91) demonstrated that cf-miR-210 is a better recurrence indicator. We concluded enhanced cf-miR-210 provides identification of early systemic melanoma recurrence. more...

Detection of circulating tumor cells (CTC) in peripheral blood has been investigated for its prognostic ability, and its potential to measure the effectiveness of treatment(s) in patients with melanoma. However, a highly sensitive and specific assay is required to detect CTC in patients' blood. We have developed a multimarker quantitative real-time reverse transcriptase polymerase chain reaction (RT-qPCR) assay for detecting CTC directly from peripheral blood specimens without the need of separating CTC from leukocytes (PBL). We selected and optimized four mRNA biomarkers (MART-1/Melan-A, MAGE-A3, PAX3, and GalNAc-T) for detection and prediction of clinical outcome in melanoma patients. Our protocol has both high sensitivity and specificity for CTC in blood specimens-detecting approximately one to five melanoma cells in 10(7) PBL. We have demonstrated the significance of this assay for serial bleed assessment of CTC in clinical trials and for daily clinical usage. more...

Objective: To investigate a cohort of melanoma patients with false negative (FN) sentinel node (SN) biopsies (SNBs) to identify the reasons for the FN result., Summary of Background Data: SNB is a highly efficient staging method in melanoma patients. However, with long-term follow-up FN SNB results of up to 25% have been reported., Methods: Seventy-four SNs from 33 patients found to have had an FN SNB were analyzed by reviewing the lymphoscintigraphy, surgical data, and histopathology, and by assessing nodal tissue using multimarker real-time quantitative reverse transcription (qRT) polymerase chain reaction, and antimony concentration measurements (as a marker of "true" SN status) using inductively coupled plasma mass spectroscopy., Results: Nine SNs (12%) from 9 patients (27%) had evidence of melanoma on histopathologic review. Twelve SNs (16%) from 10 patients (30%) were qRT(+). Four of these 12 SNs were positive on histopathology review and 8 were negative. Four patients (12%) were upstaged by qRT. Sixteen patients had their SNB histology, lymphoscintigraphy, and surgical data reviewed. Identifiable causes of the FN SNBs were not found after review of all modalities in 4 patients. SNs from all 4 patients had antimony levels indicative of an SN. Of the SNs evaluable by qRT, 1 was qRT(+) and 7 SNs from 2 patients were qRT(-)., Conclusions: An FN SN can occur because of deficiencies in nuclear medicine, surgery, or pathology. qRT can detect "occult" metastatic melanoma in SNs that have been identified as negative by histopathology. more...