Prognostic and monitoring value of circulating tumour cells in adrenocortical carcinoma: a preliminary monocentric study.

Adrenocortical carcinoma (ACC), a rare and aggressive neoplasia, presents poor prognosis when metastatic at diagnosis and limited therapies are available. Specific and sensitive markers for early diagnosis and a monitoring system of therapy and tumor evolution are urgently needed. The liquid biopsy represents a source of tumor material within a minimally invasive blood draw that allows the recovery of circulating tumor cells (CTCs). CTCs have been recently shown to be detectable in ACC. In the present paper, we evaluated the prognostic value of CTCs obtained by size-filtration in a small pilot cohort of 19 ACC patients. We found CTCs in 68% of pre-surgery and in 38% of post-surgery blood samples. In addition, CTC clusters (CTMs) and cancer associated macrophages (CAMLs) were detectable in some ACC patients. The median number of CTCs significantly decreased after the mass removal. Finally, stratifying patients in high and low pre-surgery CTC number groups, assuming the 75th percentile CTC value as cut-off, CTCs significantly predicted patients’ overall survival (log rank = 0.005), also in a multivariate analysis adjusted for age and tumor stage. In conclusion, though preliminary and performed in a small cohort of patients, our study suggests that CTC number may represent a promising marker for prognosis and disease monitoring in ACC

Application of a filtration- and isolation-by-size technique for the detection of circulating tumor cells in cutaneous melanoma

Analysis of circulating tumor cells (CTC) in the peripheral blood of cutaneous melanoma patients provides information on the metastatic process and potentially improves patient management. The isolation by size of epithelial tumor cells (ISET) is a direct method for CTC identification in which tumor cells are collected by filtration as a result of their large size. So far, ISET has been applied only to CTC detection from epithelial cancer patients, and the technique has never been applied to cutaneous melanoma patients. We herein investigated the presence of CTC by ISET in the peripheral blood of 140 subjects (87 with cutaneous melanomas, 10 subjects undergoing surgery for melanocytic nevi, 5 patients with non-melanoma skin tumors, and 38 healthy volunteers). The identification of the cells trapped in filters as CTC was supported by positivity for immunohistochemical markers and for tyrosinase mRNA by real-time RT-PCR. CTC were neither detected in the controls nor in the in situ melanoma group. In contrast, CTC were shown in 29% of patients with primary invasive melanoma and in 62.5% of metastatic melanoma patients (P<0.01). CTC detection correlated with the presence of mRNA tyrosinase in blood samples, assayed by real-time RT-PCR (P=0.001). CTC detection corroborated by suitable molecular characterization may assist in the identification and monitoring of more appropriate therapies in melanoma patients. © 2010 The Society for Investigative Dermatology

Circulating Cell-Free DNA in Dogs with Mammary Tumors: Short and Long Fragments and Integrity Index

Circulating cell-free DNA (cfDNA) has been considered an interesting diagnostic/prognostic plasma biomarker in tumor-bearing subjects. In cancer patients, cfDNA can hypothetically derive from tumor necrosis/apoptosis, lysed circulating cells, and some yet unrevealed mechanisms of active release. This study aimed to preliminarily analyze cfDNA in dogs with canine mammary tumors (CMTs). Forty-four neoplastic, 17 non-neoplastic disease-bearing, and 15 healthy dogs were recruited. Necrosis and apoptosis were also assessed as potential source of cfDNA on 78 CMTs diagnosed from the 44 dogs. The cfDNA fragments and integrity index significantly differentiated neoplastic versus non-neoplastic dogs (P<0.05), and allowed the distinction between benign and malignant lesions (P<0.05). Even if without statistical significance, the amount of cfDNA was also affected by tumor necrosis and correlated with tumor size and apoptotic markers expression. A significant (P<0.01) increase of Bcl-2 in malignant tumors was observed, and in metastatic CMTs the evasion of apoptosis was also suggested. This study, therefore, provides evidence that cfDNA could be a diagnostic marker in dogs carrying mammary nodules suggesting that its potential application in early diagnostic procedures should be further investigated

The evidence base for circulating tumour DNA blood-based biomarkers for the early detection of cancer: a systematic mapping review

Background: The presence of circulating cell-free DNA from tumours in blood (ctDNA) is of major importance to those interested in early cancer detection, as well as to those wishing to monitor tumour progression or diagnose the presence of activating mutations to guide treatment. In 2014, the UK Early Cancer Detection Consortium undertook a systematic mapping review of the literature to identify blood-based biomarkers with potential for the development of a non-invasive blood test for cancer screening, and which identified this as a major area of interest. This review builds on the mapping review to expand the ctDNA dataset to examine the best options for the detection of multiple cancer types. Methods: The original mapping review was based on comprehensive searches of the electronic databases Medline, Embase, CINAHL, the Cochrane library, and Biosis to obtain relevant literature on blood-based biomarkers for cancer detection in humans (PROSPERO no. CRD42014010827). The abstracts for each paper were reviewed to determine whether validation data were reported, and then examined in full. Publications concentrating on monitoring of disease burden or mutations were excluded. Results: The search identified 94 ctDNA studies meeting the criteria for review. All but 5 studies examined one cancer type, with breast, colorectal and lung cancers representing 60% of studies. The size and design of the studies varied widely. Controls were included in 77% of publications. The largest study included 640 patients, but the median study size was 65 cases and 35 controls, and the bulk of studies (71%) included less than 100 patients. Studies either estimated cfDNA levels non-specifically or tested for cancer-specific mutations or methylation changes (the majority using PCR-based methods). Conclusion: We have systematically reviewed ctDNA blood biomarkers for the early detection of cancer. Pre-analytical, analytical, and post-analytical considerations were identified which need to be addressed before such biomarkers enter clinical practice. The value of small studies with no comparison between methods, or even the inclusion of controls is highly questionable, and larger validation studies will be required before such methods can be considered for early cancer detection

Updates on liquid biopsy: Current trends and future perspectives for clinical application in solid tumors

Despite advances in screening and therapeutics cancer continues to be one of the major causes of morbidity and mortality worldwide. The molecular profile of tumor is routinely assessed by surgical or bioptic samples, however, genotyping of tissue has inherent limitations: it represents a single snapshot in time and it is subjected to spatial selection bias owing to tumor heterogeneity. Liquid biopsy has emerged as a novel, non-invasive opportunity of detecting and monitoring cancer in several body fluids instead of tumor tissue. Circulating tumor cells (CTCs), circulating tumor DNA (ctDNA), RNA (mRNA and microRNA), microvesicles, including exosomes and tumor “educated platelets” were recently identified as a source of genomic information in cancer patients which could reflect all subclones present in primary and metastatic lesions allowing sequential monitoring of disease evolution. In this review, we summarize the currently available information concerning liquid biopsy in breast cancer, colon cancer, lung cancer and melanoma. These promising issues still need to be standardized and harmonized across laboratories, before fully adopting liquid biopsy approaches into clinical practice

Prostate-specific antigen mRNA and protein levels in laser microdissected cells of human prostate measured by real-time reverse transcriptase-quantitative polymerase chain reaction and immuno-quantitative polymerase chain reaction

Laser-assisted microdissection has mainly been used in cancer studies to excise pure cell populations from heterogeneous tissues. Cancer and normal cells selected by laser-assisted microdissection have frequently been used for mRNA expression studies usually by reverse transcriptase-quantitative polymerase chain reaction (qPCR). Recently, real time immuno-qPCR was developed as a new tool for highly sensitive measurements of proteins. Using reverse transcriptase-qPCR and immuno-qPCR, we measured the amounts of prostate-specific antigen mRNA and its corresponding protein in homogeneous and comparable cell populations, collected from normal and cancer prostates by laser-assisted microdissection. With these techniques, prostate-specific antigen mRNA and protein were quantified over a wide range of concentrations with a sensitivity sufficient to analyze single prostate cells (LNCaP). We did not find significant differences in prostate-specific antigen protein and mRNA between normal and cancer cells. The expression of prostate-specific antigen protein and mRNA was highly correlated in both normal and pathological cells. In microdissected peritubular stromas areas of prostate cancers, the concentration of prostate-specific antigen protein was about 100 times higher than in normal prostate, indicating an increased transit of secreted prostate-specific antigen. In the same samples, prostate-specific antigen mRNA was not detectable. Our data demonstrate, for the first time, the feasibility of simultaneous application of reverse transcriptase-qPCR and immuno-qPCR in studies of homogeneous cell populations, collected by laser-assisted microdissection. The approach is expected to become a very powerful tool for expression studies in human cancers at both mRNA and protein levels

BRAF and KIT somatic mutations are present in amelanotic melanoma

he genotypic profile of rare amelanotic melanomas (AMs) has been poorly investigated, thus preventing either an accurate identification as a distinctive melanoma subtype or therapy stratification. Here, we investigated the presence of the BRAF(V600E) mutation by real-time quantitative PCR and KIT mutations (exons 11 and 17) by sequencing analysis in 33 AMs. AMs included truly' amelanotic lesions (n=19), with no melanin pigmentation upon dermoscopic inspection and hypomelanotic lesions (n=14), by definition partially pigmented lesions showing a melanin pigmentation area of less than 25% of the total surface area. The frequency of the BRAF(V600E) mutation was 70.3% in the 33 cases, a percentage that increased to 89% when only the subgroup of thin melanomas (1 mm in thickness, n=9) was considered. KIT mutations were found in 12.1% of AMs, all of which developed in nonacral sites. The identification of a relatively high frequency of BRAF(V600E) and KIT mutations in AMs may have important consequences for implementation of the novel targeted therapies now available to treat this life-threatening disease. (C) 2013 Wolters Kluwer Health vertical bar Lippincott Williams & Wilkins