Identification of TP53 mutations in circulating tumour DNA in high grade serous ovarian carcinoma using next generation sequencing technologies.

Plasma circulating tumour DNA (ctDNA) has been suggested to be a viable biomarker of response to treatment in patients with high grade serous ovarian carcinoma (HGSOC). TP53 mutations are present in more than 90% of HGSOCs but somatic variants are distributed across all exonic regions of the gene, requiring next generation sequencing (NGS) technologies for mutational analysis. In this study, we compared the suitability of the Accel (Swift) and Oncomine (ThermoFisher) panels for identification of TP53 mutations in ctDNA of HGSOC patients (N = 10).

Detection of clinical progression through plasma ctDNA in metastatic melanoma patients: a comparison to radiological progression.

Background: The validity of circulating tumour DNA (ctDNA) as an indicator of disease progression compared to medical imaging in patients with metastatic melanoma requires detailed evaluation.

Methods: Here, we carried out a retrospective ctDNA analysis of 108 plasma samples collected at the time of disease progression. We also analysed a validation cohort of 66 metastatic melanoma patients monitored prospectively after response to systemic therapy.

The Prognostic Impact of Circulating Tumour DNA in Melanoma Patients Treated with Systemic Therapies-Beyond Mutant Detection.

In this study, we evaluated the predictive value of circulating tumour DNA (ctDNA) to inform therapeutic outcomes in metastatic melanoma patients receiving systemic therapies. We analysed 142 plasma samples from metastatic melanoma patients prior to commencement of systemic therapy: 70 were treated with BRAF/MEK inhibitors and 72 with immunotherapies. Patient-specific droplet digital polymerase chain reaction assays were designed for ctDNA detection.

Circulating Tumor DNA Predicts Outcome from First-, but not Second-line Treatment and Identifies Melanoma Patients Who May Benefit from Combination Immunotherapy.

Purpose: We evaluated the predictive value of pretreatment ctDNA to inform therapeutic outcomes in patients with metastatic melanoma relative to type and line of treatment.

Experimental Design: Plasma circulating tumor DNA (ctDNA) was quantified in 125 samples collected from 110 patients prior to commencing treatment with immune checkpoint inhibitors (ICIs), as first- ( = 32) or second-line ( = 27) regimens, or prior to commencing first-line BRAF/MEK inhibitor therapy ( = 66). An external validation cohort included 128 patients commencing ICI therapies in the first- ( = 77) or second-line ( = 51) settings.

Role of Serum Vascular Endothelial Growth Factor (VEGF) as a Potential Biomarker of Response to Immune Checkpoint Inhibitor Therapy in Advanced Melanoma: Results of a Pilot Study.

The development of biomarkers predictive of response to immune checkpoint inhibitor (ICI) therapies in advanced melanoma is an area of great interest in oncology. Our study evaluated the potential role of serum vascular endothelial growth factor (VEGF) as a predictive biomarker of clinical benefit and response to treatment with ICIs. Pre-treatment peripheral blood samples were obtained from advanced melanoma patients undergoing ICI therapy as monotherapy or in combination at two tertiary care hospitals in Western Australia.

Interleukin-37 is highly expressed in regulatory T cells of melanoma patients and enhanced by melanoma cell secretome.

Immune suppression is one of the 10 hallmarks of cancer. Interleukin-37 (IL-37), a member of the IL-1 family, inhibits both innate and adaptive immunity, and has been shown to modulate immune responses in various disease conditions. Yet, IL-37 has rarely been investigated in cancer patients, and its biological role in cancer remains to be elucidated.

Immunomagnetic-Enriched Subpopulations of Melanoma Circulating Tumour Cells (CTCs) Exhibit Distinct Transcriptome Profiles.

Cutaneous melanoma circulating tumour cells (CTCs) are phenotypically and molecularly heterogeneous. We profiled the gene expression of CTC subpopulations immunomagnetic-captured by targeting either the melanoma-associated marker, MCSP, or the melanoma-initiating marker, ABCB5. Firstly, the expression of a subset of melanoma genes was investigated by RT-PCR in MCSP-enriched and ABCB5-enriched CTCs isolated from a total of 59 blood draws from 39 melanoma cases.

Prognostic Relevance of CCDC88C (Daple) Transcripts in the Peripheral Blood of Patients with Cutaneous Melanoma.

A loss of balance between G protein activation and deactivation has been implicated in the initiation of melanomas, and non-canonical Wnt signaling via the Wnt5A/Frizzled (FZD) pathway has been shown to be critical for the switch to an invasive phenotype. Daple [CCDC88C], a cytosolic guanine nucleotide exchange modulator (GEM) which enhances non-canonical Wnt5A/FZD signaling via activation of trimeric G protein, Gαi, has been shown to serve opposing roles-as an inducer of EMT and invasiveness and a potent tumor suppressor-via two isoforms, V1 (full-length) and V2 (short spliced isoform), respectively. Here we report that the relative abundance of these isoforms in the peripheral circulation, presumably largely from circulating tumor cells (CTCs), is a prognostic marker of cutaneous melanomas.

Locus-specific concordance of genomic alterations between tissue and plasma circulating tumor DNA in metastatic melanoma.

Circulating tumor DNA (ctDNA) may serve as a surrogate to tissue biopsy for noninvasive identification of mutations across multiple genetic loci and for disease monitoring in melanoma. In this study, we compared the mutation profiles of tumor biopsies and plasma ctDNA from metastatic melanoma patients using custom sequencing panels targeting 30 melanoma-associated genes. Somatic mutations were identified in 20 of 24 melanoma biopsies, and 16 of 20 (70%) matched-patient plasmas had detectable ctDNA.

Circulating tumor DNA to monitor treatment response and detect acquired resistance in patients with metastatic melanoma.

Repeat tumor biopsies to study genomic changes during therapy are difficult, invasive and data are confounded by tumoral heterogeneity. The analysis of circulating tumor DNA (ctDNA) can provide a non-invasive approach to assess prognosis and the genetic evolution of tumors in response to therapy. Mutation-specific droplet digital PCR was used to measure plasma concentrations of oncogenic BRAF and NRAS variants in 48 patients with advanced metastatic melanoma prior to treatment with targeted therapies (vemurafenib, dabrafenib or dabrafenib/trametinib combination) or immunotherapies (ipilimumab, nivolumab or pembrolizumab).

Circulating Melanoma Cell Subpopulations: Their Heterogeneity and Differential Responses to Treatment.

Metastatic melanoma is a highly heterogeneous tumor; thus, methods to analyze tumor-derived cells circulating in blood should address this diversity. Taking this into account, we analyzed, using multiparametric flow cytometry, the co-expression of the melanoma markers melanoma cell adhesion molecule and melanoma-associated chondroitin sulphate proteoglycan and the tumor-initiating markers ATP-binding cassette sub-family B member 5 (ABCB5), CD271, and receptor activator of NF-κβ (RANK) in individual circulating tumor cells (CTCs) from 40 late-stage (III-IV) and 16 early-stage (I-II) melanoma patients. CTCs were heterogeneous within and between patients, with limited co-expression between the five markers analyzed.

Detection of BRAF-V600E and V600K in melanoma circulating tumour cells by droplet digital PCR.

Objectives: Defining the BRAF mutation status in metastatic melanoma patients is critical to selecting patients for therapeutic treatment with targeted therapies. Circulating tumour cells (CTCs) can provide an alternative source of contemporaneous tumour genetic material. However methodologies to analyse the presence of rare mutations in a background of wild-type DNA requires a detailed assessment.