Laser transfer for circulating tumor cell isolation in liquid biopsy.

75Cancer research has found in the recent years a formidable ally in liquid biopsy, a noninvasive technique that allows the study of circulating tumor cells (CTCs) and biomolecules involved in the dynamics of cancer spread like cell-free nucleid acids or tumor-derived extracellular vesicles. However, single-cell isolation of CTCs with high viability for further genetic, phenotypic, and morphological characterization remains a challenge. We present a new approach for single CTC isolation in enriched blood samples using a liquid laser transfer (LLT) process, adapted from standard laser direct write techniques. In order to completely preserve the cells from direct laser irradiation, we used an ultraviolet laser to produce a blister-actuated laser-induced forward transfer process (BA-LIFT). Using a plasma-treated polyimide layer for blister generation, we completely shield the sample from the incident laser beam. The optical transparency of the polyimide allows direct cell targeting using a simplified optical setup, in which the laser irradiation module, standard imaging, and fluorescence imaging share a common optical path. Peripheral blood mononuclear cells (PBMCs) were identified by fluorescent markers, while target cancer cells remained unstained. As a proof of concept, we were able to isolate single MDA-MB-231 cancer cells using this negative selection process. Unstained target cells were isolated and culture while their DNA was sent for single-cell sequencing (SCS). Our approach appears to be an effective approach to isolate single CTCs, preserving cell characteristics in terms of cell viability and potential for further SCS.

Technical Challenges for CTC Implementation in Breast Cancer.

Breast cancer is the most common neoplasm in women worldwide. Tissue biopsy, currently the gold standard to obtain tumor molecular information, is invasive and might be affected by tumor heterogeneity rendering it incapable to portray the complete dynamic picture by the absence of specific genetic changes during the evolution of the disease. In contrast, liquid biopsy can provide unique opportunities for real-time monitoring of disease progression, treatment response and for studying tumor heterogeneity combining the information of DNA that tumors spread in the blood (circulating tumor DNA) with CTCs analysis. In this review, we analyze the technical and biological challenges for isolation and characterization of circulating tumor cells from breast cancer patients. Circulating tumor cell (CTC) enumeration value is included in numerous clinical studies due to the prognostic's role of these cells. Despite this, there are so many questions pending to answer. How to manage lymphocytes background, how to distinguish the CTCs subtypes or how to work with frozen samples, are some of the issues that will discuss in this review. Based on our experience, we try to address these issues and other technical limitations that should be solved to optimize the standardization of protocols, sample extraction procedures, circulating-tumor material isolation (CTCs vs. ctDNA) and the very diverse methodologies employed, aiming to consolidate the use of CTCs in the clinic. Furthermore, we think that new approaches focusing on isolation CTCs in other body fluids such as cerebrospinal or ascitic fluid are necessary to increase the opportunities of circulating tumor cells in the practice clinic as well as to study the promising role of CTC clusters and their prognostic value in metastatic breast cancer.

Activity of docetaxel, carboplatin, and doxorubicin in patient-derived triple-negative breast cancer xenografts.

Triple-negative breast cancer (TNBC) is highly responsive to neoadjuvant polychemotherapy regimens including anthracyclines, taxanes, and, more recently, carboplatin. However, there is inadequate information on the individual contribution of each of these agents to the global activity of the combinations, and the use of combinations of up to four of these drugs is associated with relevant toxicity. Identifying single-drug activity in the clinical neoadjuvant setting is challenging. We developed patient-derived xenografts (PDXs) from several chemotherapy-naïve TNBC samples to assess the antitumor activity of single drugs and combinations of drugs. PDXs were established from chemotherapy-naïve TNBC samples. Nine TNBC PDX models (all of which corresponded to a basal-like phenotype according to the PAM50 classifier) were treated with carboplatin, docetaxel, and doxorubicin and the combination of docetaxel and carboplatin. Only one of nine PDX models showed sensitivity to doxorubicin, while eight of nine PDX models showed sensitivity to docetaxel and carboplatin as single agents. The 3 PDX models derived from patients with gBRCA-1 or gPALB2 mutations were very sensitive to carboplatin single agent. All 6 PDX models from patients without hereditary germ-line mutations showed increased sensitivity to the combination of docetaxel and carboplatin. In the present study, docetaxel and carboplatin single agents were active drugs against basal-like TNBC, while doxorubicin monotherapy showed low activity. The combination of docetaxel and carboplatin was more effective than the drugs used as single agents, except in the PDX from patients with gBRCA1/PALB2 mutations.

Intratumoral nanoplexed poly I:C BO-112 in combination with systemic anti-PD-1 for patients with anti-PD-1-refractory tumors.

Intratumoral therapies, especially Toll-like receptor agonists, can trigger both the innate and adaptive immune systems. BO-112 is a nanoplexed form of polyinosinic:polycytidylic acid (poly I:C) that induces local and systemic immunotherapeutic effects in mouse models. In a multicenter phase 1 clinical trial, repeated intratumoral administrations of BO-112 induced an increase in tumor cell necrosis and apoptosis, as well as augmented immune reactivity according to gene expression profiling. The first three cohorts receiving BO-112 as a monotherapy resulted in a recommended dose of 1 mg that could be safely repeated. Two grade 3 to 4 adverse reactions in the form of reversible thrombocytopenia were reported. In a fourth cohort of 28 patients with tumors that had primary resistance to anti-programmed cell death protein-1 (PD-1), the combination of intratumoral BO-112 with nivolumab or pembrolizumab was also well tolerated, and 3 patients (2 with melanoma and 1 with renal cell carcinoma) achieved partial responses, with 10 more patients having stable disease at 8 to 12 weeks. Thus, local BO-112 combined with a systemic anti-PD-1 agent might be a strategy to revert anti-PD-1 resistance.

Concordance of Genomic Variants in Matched Primary Breast Cancer, Metastatic Tumor, and Circulating Tumor DNA: The MIRROR Study.

PURPOSE: Genetic heterogeneity between primary tumors and their metastatic lesions has been documented in several breast cancer studies. However, the selection of therapy for patients with metastatic breast cancer and the search for biomarkers for targeted therapy are often based on findings from the primary tumor, mainly because of the difficulty of distant metastasis core biopsies. New methods for monitoring genomic changes in metastatic breast cancer are needed (ie, circulating tumor DNA [ctDNA] genomic analysis). The objectives of this study were to assess the concordance of genomic variants between primary and metastatic tumor tissues and the sensitivity of plasma ctDNA analysis to identify variants detected in tumor biopsies. PATIENTS AND METHODS: Next-generation sequencing technology was used to assess the genomic mutation profile of a panel of 54 cancer genes in matched samples of primary tumor, metastatic tumor, and plasma from 40 patients with metastatic breast cancer. RESULTS: Using Ion Torrent technology (ThermoFisher Scientific, Waltham, MA), we identified 110 variants that were common to the primary and metastatic tumors. ctDNA analysis had a sensitivity of 0.972 in detecting variants present in both primary and metastatic tissues. In addition, we identified 13 variants in metastatic tissue and ctDNA not present in primary tumor. CONCLUSION: We identified genomic variants present in metastatic biopsies and plasma ctDNA that were not present in the primary tumor. Deep sequencing of plasma ctDNA detected most DNA variants previously identified in matched primary and metastatic tissues. ctDNA might aid in therapy selection and in the search for biomarkers for drug development in metastatic breast cancer.

Pathological Response in a Triple-Negative Breast Cancer Cohort Treated with Neoadjuvant Carboplatin and Docetaxel According to Lehmann's Refined Classification.

Purpose: Triple-negative breast cancer (TNBC) requires the iden- tification of reliable predictors of response to neoadjuvant chemotherapy (NACT). For this purpose, we aimed to evaluate the performance of the TNBCtype-4 classifier in a cohort of patients with TNBC treated with neoadjuvant carboplatin and docetaxel (TCb).Methods: Patients with TNBC were accrued in a nonrandomized trial of neoadjuvant carboplatin AUC 6 and docetaxel 75 mg/m2 for six cycles. Response was evaluated in terms of pathologic complete response (pCR, ypT0/is ypN0) and residual cancer burden by Symmans and colleagues. Lehmann's subtyping was performed using the TNBCtype online tool from RNAseq data, and germline sequencing of a panel of seven DNA damage repair genes was conducted.Results: Ninety-four out of the 121 patients enrolled in the trial had RNAseq available. The overall pCR rate was 44.7%. Lehmann subtype distribution was 34.0% BL1, 20.2% BL2, 23.4% M, 14.9% LAR, and 7.4% were classified as ER+. Response to NACT with TCb was significantly associated with Lehmann subtype (P = 0.027), even in multivariate analysis including tumor size and nodal involvement, with BL1 patients achieving the highest pCR rate (65.6%), followed by BL2 (47.4%), M (36.4%), and LAR (21.4%). BL1 was associated with a significant younger age at diagnosis and higher ki67 values. Among our 10 germline mutation carriers, 30% were BL1, 40% were BL2, and 30% were M.Conclusions: TNBCtype-4 is associated with significantly different pCR rates for the different subtypes, with BL1 and LAR displaying the best and worse responses to NACT, respectively. Clin Cancer Res; 24(8); 1845-52. ©2018 AACR.

Frequency of germline DNA genetic findings in an unselected prospective cohort of triple-negative breast cancer patients participating in a platinum-based neoadjuvant chemotherapy trial.

We describe the status and frequency of germline DNA genetic findings in an unselected prospective cohort of triple negative breast cancer patients participating in a platinum-based neoadjuvant chemotherapy trial. Study population includes 124 consecutive patients with stage II-III TNBC from a trial exploring the antitumor activity of neoadjuvant carboplatin/docetaxel chemotherapy enrolled between 2012 and March 2015, to determine the frequency of germline DNA genetic mutations. 17.1 % of the patients with germline DNA tested had deleterious mutations in any of the analyzed genes (12.38 % in BRCA1, 1.9 % in BRCA2 and BARD1 and 0.95 % in RAD51D). Attending the intrinsic subtype, all the BRCA1/2 carriers tested had basal-like subtype. Among wild-type (WT) patients, 70.11 % had basal subtype, 16.09 % HER2 enriched, 1.15 % Luminal B, and 4.60 % Normal-like. Mean age at diagnosis was significantly lower in mutation-carriers compared with no carriers (43.72 vs 53.10, p = 0.004). 3 BRCA1/2 carriers were detected between 51 and 60 years, and only one deleterious mutation (BARD1) over 60 years. A positive familiar history of breast and ovarian cancer was more frequent in patients with deleterious mutations (39.39 vs 17.94 %, p = 0.043). Our study confirms the prevalence of BRCA1/2 mutations in TNBC patients. TNBC should therefore be considered by itself as a criterion for BRCA1/2 genetic testing. Determination of other breast cancer predisposition genes implicated in homologous recombination should also be discussed in this population. However, no definitive conclusions can be reached due to the low prevalence and the uncertain clinical impact of most of the genes included.

Low DPP4 expression and activity in multiple sclerosis.

Multiple sclerosis (MS) is a prototypic Th1/Th17 chronic autoimmune disease of the central nervous system. Dipeptidyl peptidase 4 (DPP4 or CD26) is a multifunctional molecule involved in autoimmune diseases' pathophysiology. We sought to integrate disparate pieces of data and analyze the plasma levels of sDPP4, DPP activity and DPP4 surface expression on T-cells in 129 MS patients with different clinical forms and 53 healthy controls, across two independent cohorts. Herein, we provide new evidence that sDPP4 concentration and DPP activity are significantly lower in MS patients than controls (p < 0.0001 and p < 0.01, respectively). In contrast, the frequency of circulating CD8(+)DPP4(hi) T-cells (p = 0.02) was increased in MS patients. This is the first study that simultaneously analyzes DPP4 expression and function in a large cohort of MS patients. Our data indicate a putative role for DPP4 in MS pathophysiology and suggest that a deeper understanding of surface versus shed DPP4 biology is warranted.

SPIB, a novel immunohistochemical marker for human blastic plasmacytoid dendritic cell neoplasms: characterization of its expression in major hematolymphoid neoplasms.

SPIB is an Ets transcription factor that is expressed exclusively in mature B cells, T-cell progenitors, and plasmacytoid dendritic cells. In the present study, we developed a novel mAb against the SPIB protein and characterized its expression in major hematolymphoid neoplasms, including a series of 45 cases of blastic plasmacytoid dendritic cell (BPDC) neoplasms and their potential cutaneous mimics. We found that SPIB is expressed heterogeneously among B- and T-cell lymphoma types. Interestingly, SPIB is expressed in a large proportion of nongerminal center type DLBCLs. In cutaneous neoplasms, SPIB is overexpressed in all BPDC neoplasms, but none of its cutaneous mimics. SPIB remains overexpressed in all cases that lack 1 or 2 of the markers used for BPDC neoplasms (ie, CD4, CD56, TCL1, and CD123). We conclude that SPIB expression can be used as a tool for diagnosing BPDC neoplasms, but it needs to be tested in conjunction with the growing arsenal of markers for human plasmacytoid dendritic cells.

Perforin expression by CD4+ regulatory T cells increases at multiple sclerosis relapse: sex differences.

Multiple sclerosis (MS) represents the leading cause of neurological deficit among young adults, affecting women more frequently than men. In MS, the extent of central nervous system lesions is determined by the net balance between self-reactive and regulatory T-cells at any given time, among other factors, as well as by the effect of inflammatory response. Here, we studied both CD4+ and CD8+ T(Reg) in parallel in blood and CSF during MS relapse. A recruitment of both regulatory CD4+ and CD8+ T cells (T(Reg)) within the cerebrospinal fluid (CSF) takes place during MS relapse. Not previously described, the presence of CD4+ T(Reg) in CSF was higher in women than in men, which could account for the sexual dimorphism in the incidence of MS. A direct correlation between plasma oestradiol (E2) and IL-2 levels was observed, in line with a putative circuit of E2 and perforin expression by CD4+ T(Reg) playing a role in MS. Also, serum IFN-alpha was higher in females, with direct correlation with serum E2 levels. This is the first study to analyze perforin expression by CD4+ T(Reg) in MS, which was greatly enhanced in CSF, what points out a relevant role of this molecule in the suppressive effects of the CD4+ T(Reg) in MS, and contributes to the understanding of MS pathophysiology.

[Intravenous immunoglobulin: immunomodulatory key of the immune system]. / Inmunoglobulinas intravenosas: llave inmunomoduladora del sistema inmunológico.

The mechanisms of action of intravenous immunoglobulins (IVIG) are complex and mostly reproduce those of the natural immunoglobulin G (IgG) in our organism. The therapeutic doses used range from substitutive (200-400mg/kg of body weight) in immunodeficiencies to high doses (1-2g/kg of body weight) in autoimmune or inflammatory diseases. The paradoxical pro- or anti-inflammatory effects of IVIG are based on the modulation of the expression of activating versus inhibitory Fc receptors, the type and stage of maturation of the target cell. This huge diversity of actions may explain the extensive and varied range of clinical applications of IVIG nowadays (immunodeficiencies, autoimmune diseases, degenerative diseases such as Alzheimer's, and cancer). On the other hand, biological therapies with monoclonal antibodies mostly consist of IgG molecules with unique antigen specificity, and currently represent a therapeutic field expanding in various pathologies including cancer and diseases of immunological basis. The effects of IgG are added to their specific effects on molecules target.

Exome sequencing identifies MAX mutations as a cause of hereditary pheochromocytoma.

Hereditary pheochromocytoma (PCC) is often caused by germline mutations in one of nine susceptibility genes described to date, but there are familial cases without mutations in these known genes. We sequenced the exomes of three unrelated individuals with hereditary PCC (cases) and identified mutations in MAX, the MYC associated factor X gene. Absence of MAX protein in the tumors and loss of heterozygosity caused by uniparental disomy supported the involvement of MAX alterations in the disease. A follow-up study of a selected series of 59 cases with PCC identified five additional MAX mutations and suggested an association with malignant outcome and preferential paternal transmission of MAX mutations. The involvement of the MYC-MAX-MXD1 network in the development and progression of neural crest cell tumors is further supported by the lack of functional MAX in rat PCC (PC12) cells and by the amplification of MYCN in neuroblastoma and suggests that loss of MAX function is correlated with metastatic potential.

Immunohistochemical analysis of HLDA9 Workshop antibodies against cell-surface molecules in reactive and neoplastic lymphoid tissues.

The study of human leukocyte antigens, predominantly by monoclonal antibody (mAb) techniques, has become a fundamental part of basic research and clinical investigation. In particular, mAbs have allowed a more precise phenotypic dissection of lymphocyte subsets and have increased our understanding of the mechanisms that regulate humoral immunity and tumour transformation. In the present study we have investigated the expression, in both reactive and neoplastic lymphoid tissues, of a panel of HLDA9 mAbs (TRAIL-R2 (CD262), CCR6 (CD196), HVEM (CD270), Galectin-3 and BAFF-R (CD268)) capable of recognizing their target molecules in paraffin-embedded tissue sections. A series of reactive lymphoid tissues and B and T cell lymphomas (151 cases) were studied, using whole sections and tissue microarrays (T.M.A.). The most interesting results were obtained from the Galectin-3 study. In human lymphomas our data are consistent with the results previously described that showed that Galectin-3 is expressed in anaplastic large cell lymphoma (ALCL). Moreover, we provide additional information of Galetin-3 expression in other lymphoma types. In T cell lymphomas, Galectin-3 was strongly expressed by a significant number of peripheral (PTCL 12/43) and cutaneous T cell lymphomas (CTCL 6/24) while in B cell lymphoma only a small proportion of follicular (FL 2/10) and diffuse large B cell lymphomas (DLBCL 3/10) were positives. Our study encourage further investigations into the potential role that TRAIL-R2, CD196, HVEM, Galectin-3 and BAFF-R proteins may play in lymphocyte development and differentiation, but also constitute an additional tool for the study of lymphoid subpopulations and lymphoproliferative disorders.