Maintenance Pembrolizumab Therapy in Patients with Metastatic HER2-negative Breast Cancer with Prior Response to Chemotherapy.

PURPOSE: Accumulating toxicities hinder indefinite chemotherapy for many patients with metastatic/recurrent HER2-negative breast cancer. We conducted a phase II trial of pembrolizumab monotherapy following induction chemotherapy to determine the efficacy of maintenance immunotherapy in patients with metastatic HER2-negative inflammatory breast cancer (IBC) and non-IBC triple-negative breast cancer (TNBC) and a biomarker study. PATIENTS AND METHODS: Patients with a complete response, partial response, or stable disease (SD) after at least three cycles of chemotherapy for HER2-negative breast cancer received pembrolizumab, regardless of programmed death-ligand 1 expression. Pembrolizumab (200 mg) was administered every 3 weeks until disease progression, intolerable toxicity, or 2 years of pembrolizumab exposure. The endpoints included the 4-month disease control rate (DCR), progression-free survival (PFS), overall survival, and response biomarkers in the blood. RESULTS: Of 43 treated patients, 11 had metastatic IBC and 32 non-IBC TNBC. The 4-month DCR was 58.1% [95% confidence interval (CI), 43.4-72.9]. For all patients, the median PFS was 4.8 months (95% CI, 3.0-7.1 months). The toxicity profile was similar to the previous pembrolizumab monotherapy study. Patients with high T-cell clonality at baseline had a longer PFS with pembrolizumab treatment than did those with low T-cell clonality (10.4 vs. 3.6 months, P = 0.04). Patients who achieved SD also demonstrated a significant increase in T-cell clonality during therapy compared with those who did not achieve SD (20% vs. 5.9% mean increase, respectively; P = 0.04). CONCLUSIONS: Pembrolizumab monotherapy achieved durable treatment responses. Patients with a high baseline T-cell clonality had prolonged disease control with pembrolizumab.

The Clinicopathologic Features and Molecular Signatures of Blastoid High-Grade B Cell Lymphoma, Not Otherwise Specified.

A small subset of high-grade B-cell lymphoma (HGBL) with blastoid morphology remains poorly understood. We assessed 55 cases of blastoid HGBL, not otherwise specified (NOS) and compared their clinicopathologic characteristics with those of 81 non-blastoid HGBL-NOS and 62 blastoid HGBL with MYC and BCL2, with or without BCL6 rearrangements (double/triple-hit lymphoma [D/THL]). Patients with blastoid HGBL-NOS showed similar clinicopathologic features to patients with blastoid D/THLs and non-blastoid HGBL-NOS, except more frequently with a history of low-grade B-cell lymphoma, bone marrow involvement, and BCL2 rearrangement (P < .05) compared to the latter. MYC rearrangement (MYC-R), detected in 40% of blastoid HGBL-NOS, was associated with aggressive clinicopathologic features and poorer overall survival, even worse than that of blastoid D/THL (P < .05). Transcriptome profiling revealed a distinct gene expression pattern with differentially expressed genes enriched in MYC and P53-targeted genes in MYC-R blastoid HGBL-NOS. Fifty-two percent of blastoid HGBL-NOS had a double hit-like signature, similar to non-blastoid HGBL-NOS (P = .73). The overall survival of the blastoid HGBL-NOS group was similar to that of the blastoid D/THL group but appeared poorer than that of its non-blastoid counterparts (P = .07). Taken together, blastoid HGBL-NOS is an aggressive B-cell lymphoma that shares overlapping clinicopathologic and genetic features with non-blastoid HGBL-NOS. MYC-R in patients with blastoid HGBL-NOS identifies a highly aggressive subgroup with distinct aggressive clinicopathologic features, unique molecular signatures, and a dismal clinical outcome.

Analytical performance of the FDA-cleared Parsortix® PC1 system.

Introduction: The Parsortix® PC1 system, Food and Drug Administration (FDA) cleared for use in metastatic breast cancer (MBC) patients, is an epitope-independent microfluidic device for the capture and harvest of circulating tumor cells from whole blood based on cell size and deformability. This report details the analytical characterization of linearity, detection limit, precision, and reproducibility for this device. Methods: System performance was determined using K2-EDTA blood samples collected from self-declared healthy female volunteers (HVs) and MBC patients spiked with prelabeled cultured breast cancer cell lines (SKBR3, MCF7, or Hs578T). Samples were processed on Parsortix® PC1 systems and captured cells were harvested and enumerated. Results: The system captured and harvested live SKBR3, MCF7, and Hs578T cells and fixed SKBR3 cells linearly between 2 and ~100 cells, with average harvest rates of 69%, 73%, 79%, and 90%, respectively. To harvest ≥1 cell ≥95% of the time, the system required 3, 5 or 4 live SKBR3, MCF7 or Hs578T cells, respectively. Average harvest rates from precision studies using 5, 10, and ~50 live cells spiked into blood for each cell line ranged from 63.5% to 76.2%, with repeatability and reproducibility percent coefficient of variation (%CV) estimates ranging from 12.3% to 32.4% and 13.3% to 34.1%, respectively. Average harvest rates using ~20 fixed SKBR3 cells spiked into HV and MBC patient blood samples were 75.0% ± 16.1% (%CV = 22.3%) and 68.4% ± 14.3% (%CV = 21.1%), respectively. Conclusions: These evaluations demonstrate the Parsortix® PC1 system linearly and reproducibly harvests tumor cells from blood over a range of 1 to ~100 cells.

Phenotypic Plasticity in Circulating Tumor Cells Is Associated with Poor Response to Therapy in Metastatic Breast Cancer Patients.

Circulating tumor cells (CTCs) are indicators of metastatic spread and progression. In a longitudinal, single-center trial of patients with metastatic breast cancer starting a new line of treatment, a microcavity array was used to enrich CTCs from 184 patients at up to 9 timepoints at 3-month intervals. CTCs were analyzed in parallel samples from the same blood draw by imaging and by gene expression profiling to capture CTC phenotypic plasticity. Enumeration of CTCs by image analysis relying primarily on epithelial markers from samples obtained before therapy or at 3-month follow-up identified the patients at the highest risk of progression. CTC counts decreased with therapy, and progressors had higher CTC counts than non-progressors. CTC count was prognostic primarily at the start of therapy in univariate and multivariate analyses but had less prognostic utility at 6 months to 1 year later. In contrast, gene expression, including both epithelial and mesenchymal markers, identified high-risk patients after 6-9 months of treatment, and progressors had a shift towards mesenchymal CTC gene expression on therapy. Cross-sectional analysis showed higher CTC-related gene expression in progressors 6-15 months after baseline. Furthermore, patients with higher CTC counts and CTC gene expression experienced more progression events. Longitudinal time-dependent multivariate analysis indicated that CTC count, triple-negative status, and CTC expression of FGFR1 significantly correlated with inferior progression-free survival while CTC count and triple-negative status correlated with inferior overall survival. This highlights the utility of protein-agnostic CTC enrichment and multimodality analysis to capture the heterogeneity of CTCs.

Gene expression profiling of circulating tumor cells captured by MicroCavity Array is superior to enumeration in demonstrating therapy response in patients with newly diagnosed advanced and locally advanced non-small cell lung cancer.

Background: Circulating tumor cells (CTCs) are a promising non-invasive tool for monitoring therapy response. The only Food and Drug Administration (FDA)-approved test is limited to enumeration of epithelial CTC without further characterization and is not approved for the management of non-small cell lung cancer (NSCLC). Here we use a MicroCavity Array (MCA) system to capture CTC agnostic of epithelial markers for further molecular testing in NSCLC. Methods: CTCs were enumerated by fluorescent microscopy as longitudinal sampling throughout disease management from 213 NSCLC patients. CTC-enriched samples from a subset of 127 patients were interrogated for gene expression by reverse transcription polymerase chain reaction (RT-PCR) using a customized pre-selected panel of 20 genes. Results: At least 1 CTC was detected by enumeration in 53.8% of samples. Most patients had fewer than 5 CTCs (91%) and the highest observed count was 35 CTCs. Enumeration of single CTCs was not prognostic, although detection of CTC clusters at any time point was associated with increased risk of progression [hazard ratio (HR) 3.00, 95% confidence interval (CI): 1.1-8.2, P=0.0318]. In contrast, 124 (97.6%) patients with samples interrogated for gene expression had at least 1 gene detectable in at least 1 sample, and 101 (79.5%) had at least one elevated epithelial gene in at least one timepoint. High expression of BCL2, CD274 [programmed death-ligand 1 (PD-L1)], CDH1, EPCAM, FGFR1, FN1, KRT18, MET and MUC1 were associated with poor prognosis. Patients with CTCs positive for at least 3 epithelial genes at baseline all progressed within 10 months (HR 8.2, P<0.001, 95% CI: 3.2-21.1). BCL2, CD274 (PD-L1), EPCAM and MUC1 remained significant independent prognostic factors in multivariate, time-dependent analyses of progression and death. Conclusions: The selective profile of CTC genes and identification of CTC clusters better correlated with prognosis than enumeration of enriched CTC in NSCLC patients in this study.

Moringa isothiocyanate-1 inhibits LPS-induced inflammation in mouse myoblasts and skeletal muscle.

This study aims to investigate the anti-inflammatory effects of moringa isothiocyanate-1 (MIC-1) extracted from seeds of Moringa oleifera Lam. in lipopolysaccharide (LPS)-induced inflammation models. MIC-1 decreased nitric oxide production and reduced the expression of pro-inflammatory markers (TNF-α, Ifn-α, IL-1ß, IL-6) in C2C12 myoblasts. The daily oral treatment of MIC-1 (80 mg/kg) for three days significantly reduced the expression of pro-inflammatory markers in gastrocnemius muscle tissue of LPS-treated C57BL/6 male mice. Transcriptomic analysis provided further insights into the inhibitory effects of MIC-1 on the LPS-induced inflammation, which suggested that MIC-1 affects inflammation and immunity-related genes in myoblasts and skeletal muscle tissue. MIC-1 inhibited the nuclear accumulation of the nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) in the LPS-treated myoblasts. Our data support the hypothesis that the MIC-1's effects in the muscle cells are mediated through the inhibition of the NF-κB translocation in the nucleus, which, in turn, results in immunomodulating and anti-inflammatory responses at the gene expression levels.

EGFR is a master switch between immunosuppressive and immunoactive tumor microenvironment in inflammatory breast cancer.

Inflammatory breast cancer (IBC), the most aggressive breast cancer subtype, is driven by an immunosuppressive tumor microenvironment (TME). Current treatments for IBC have limited efficacy. In a clinical trial (NCT01036087), an anti-EGFR antibody combined with neoadjuvant chemotherapy produced the highest pathological complete response rate ever reported in patients with IBC having triple-negative receptor status. We determined the molecular and immunological mechanisms behind this superior clinical outcome. Using novel humanized IBC mouse models, we discovered that EGFR-targeted therapy remodels the IBC TME by increasing cytotoxic T cells and reducing immunosuppressive regulatory T cells and M2 macrophages. These changes were due to diminishing immunosuppressive chemokine expression regulated by transcription factor EGR1. We also showed that induction of an immunoactive IBC TME by an anti-EGFR antibody improved the antitumor efficacy of an anti-PD-L1 antibody. Our findings lay the foundation for clinical trials evaluating EGFR-targeted therapy combined with immune checkpoint inhibitors in patients with cancer.

A Multi-Center Clinical Study to Harvest and Characterize Circulating Tumor Cells from Patients with Metastatic Breast Cancer Using the Parsortix® PC1 System.

Circulating tumor cells (CTCs) captured from the blood of cancer patients may serve as a surrogate source of tumor material that can be obtained via a venipuncture (also known as a liquid biopsy) and used to better understand tumor characteristics. However, the only FDA-cleared CTC assay has been limited to the enumeration of surface marker-defined cells and not further characterization of the CTCs. In this study, we tested the ability of a semi-automated device capable of capturing and harvesting CTCs from peripheral blood based on cell size and deformability, agnostic of cell-surface markers (the Parsortix® PC1 System), to yield CTCs for evaluation by downstream techniques commonly available in clinical laboratories. The data generated from this study were used to support a De Novo request (DEN200062) for the classification of this device, which the FDA recently granted. As part of a multicenter clinical trial, peripheral blood samples from 216 patients with metastatic breast cancer (MBC) and 205 healthy volunteers were subjected to CTC enrichment. A board-certified pathologist enumerated the CTCs from each participant by cytologic evaluation of Wright-Giemsa-stained slides. As proof of principle, cells harvested from a concurrent parallel sample provided by each participant were evaluated using one of three additional evaluation techniques: molecular profiling by qRT-PCR, RNA sequencing, or cytogenetic analysis of HER2 amplification by FISH. The study demonstrated that the Parsortix® PC1 System can effectively capture and harvest CTCs from the peripheral blood of MBC patients and that the harvested cells can be evaluated using orthogonal methodologies such as gene expression and/or Fluorescence In Situ Hybridization (FISH).

Genomic analysis of 1,25-dihydroxyvitamin D3 action in mouse intestine reveals compartment and segment-specific gene regulatory effects.

1,25-dihydroxyvitamin D (VD) regulates intestinal calcium absorption in the small intestine (SI) and also reduces risk of colonic inflammation and cancer. However, the intestine compartment-specific target genes of VD signaling are unknown. Here, we examined VD action across three functional compartments of the intestine using RNA-seq to measure VD-induced changes in gene expression and Chromatin Immunoprecipitation with next generation sequencing to measure vitamin D receptor (VDR) genomic binding. We found that VD regulated the expression of 55 shared transcripts in the SI crypt, SI villi, and in the colon, including Cyp24a1, S100g, Trpv6, and Slc30a10. Other VD-regulated transcripts were unique to the SI crypt (162 up, 210 down), villi (199 up, 63 down), or colon (102 up, 28 down), but this did not correlate with mRNA levels of the VDR. Furthermore, bioinformatic analysis identified unique VD-regulated biological functions in each compartment. VDR-binding sites were found in 70% of upregulated genes from the colon and SI villi but were less common in upregulated genes from the SI crypt and among downregulated genes, suggesting some transcript-level VD effects are likely indirect. Consistent with this, we show that VD regulated the expression of other transcription factors and their downstream targets. Finally, we demonstrate that compartment-specific VD-mediated gene expression was associated with compartment-specific VDR-binding sites (<30% of targets) and enrichment of intestinal transcription factor-binding motifs within VDR-binding peaks. Taken together, our data reveal unique spatial patterns of VD action in the intestine and suggest novel mechanisms that could account for compartment-specific functions of this hormone.

Silver Nitrate-coated versus Standard Indwelling Pleural Catheter for Malignant Effusions: The SWIFT Randomized Trial.

Rationale: Tunneled, indwelling pleural catheters (IPCs) have been demonstrated to be an effective method of managing malignant pleural effusions. However, they allow pleurodesis and can therefore be removed in only a subset of patients. A novel, silver nitrate-coated IPC was developed with the intention of creating a rapid, effective chemical pleurodesis to allow more frequent and earlier catheter removal. This study represents the pivotal clinical trial evaluating that catheter versus the standard IPC. Objectives: To compare the efficacy of a novel silver nitrate-eluting indwelling pleural catheter (SNCIPC) with that of a standard, uncoated catheter. Methods: The SWIFT [A Pivotal Multi-Center, Randomized, Controlled, Single-Blinded Study Comparing the Silver Nitrate-Coated Indwelling Pleural Catheter (SNCIPC) to the Uncoated PleurX® Pleural Catheter for the Management of Symptomatic, Recurrent, Malignant Pleural Effusions] trial was a multicenter, parallel-group, randomized, controlled, patient-blind trial. Central randomization occurred according to a computer-generated schedule, stratified by site. Recruitment was from 17 secondary or tertiary care hospitals in the United States and 3 in the United Kingdom and included adult patients with malignant pleural effusion needing drainage, without evidence of lung entrapment or significant loculation. The intervention group underwent insertion of an SNCIPC with maximal fluid drainage, followed by a tapering drainage schedule. The control group received a standard, uncoated catheter. Follow-up was conducted until 90 days. The primary outcome measure was pleurodesis efficacy, measured by fluid drainage, at 30 days. Results: A total of 119 patients were randomized. Five withdrew before receiving treatment, leaving 114 (77 SNCIPC, 37 standard IPC) for analysis. The mean age was 66 years (standard deviation, 11). More patients in the SNCIPC group were inpatients (39% vs. 14%; P = 0.009). For the primary outcome, pleurodesis rates were 12 (32%) of 37 in the control group and 17 (22%) of 77 in the SNCIPC group (rate difference, -0.10; 95% confidence interval, -0.30 to 0.09). Median time to pleurodesis was 11 days (interquartile range, 9 to 23) in the control group and 4 days (interquartile range, 2 to 15) in the SNCIPC group. No significant difference in treatment-related adverse event rates was noted between groups. Conclusions: The SNCIPC did not improve pleurodesis efficacy compared with a standard IPC. This study does not support the wider use of the SNCIPC device. Clinical trial registered with www.clinicaltrials.gov (NCT02649894).

Ensemble of nucleic acid absolute quantitation modules for copy number variation detection and RNA profiling.

Current gold standard for absolute quantitation of a specific DNA sequence is droplet digital PCR (ddPCR), which has been applied to copy number variation (CNV) detection. However, the number of quantitation modules in ddPCR is limited by fluorescence channels, which thus limits the CNV sensitivity due to sampling error following Poisson distribution. Here we develop a PCR-based molecular barcoding NGS approach, quantitative amplicon sequencing (QASeq), for accurate absolute quantitation scalable to over 200 quantitation modules. By attaching barcodes to individual target molecules with high efficiency, 2-plex QASeq exhibits higher and more consistent conversion yield than ddPCR in absolute molecule count quantitation. Multiplexed QASeq improves CNV sensitivity allowing confident distinguishment of 2.05 ploidy from normal 2.00 ploidy. We apply multiplexed QASeq to serial longitudinal plasma cfDNA samples from patients with metastatic ERBB2+ (HER2+ ) breast cancer seeking association with tumor progression. We further show an RNA QASeq panel for targeted expression profiling.

Identification of the JNK-Active Triple-Negative Breast Cancer Cluster Associated With an Immunosuppressive Tumor Microenvironment.

BACKGROUND: Although an immunosuppressive tumor microenvironment (TME) is key for tumor progression, the molecular characteristics associated with the immunosuppressive TME remain unknown in triple-negative breast cancer (TNBC). Our previous functional proteomic study of TNBC tumors identified that C-JUN N-terminal kinase (JNK) pathway-related molecules were enriched in a cluster associated with the inflammatory pathway. However, the role of the JNK pathway in the TNBC TME is still unclear. METHODS: Transcriptomic analysis was conducted using The Cancer Genome Atlas datasets. The effect of JNK-IN-8, a covalent pan-JNK inhibitor, on TNBC tumor growth, lung metastasis, and the TME was measured in TNBC syngeneic mouse models (n = 13 per group). Tumor (n = 43) or serum (n = 46) samples from TNBC patients were analyzed using multiplex immunohistochemistry or Luminex assay. All statistical tests were 2-sided. RESULTS: CIBERSORT analysis revealed that TNBC patients with high phosphorylated JNK level (n = 47) had more regulatory T cell (Treg) infiltration than those with a low phosphorylated JNK level (n = 47) (P = .02). Inhibition of JNK signaling statistically significantly reduced tumor growth (P < .001) and tumor-infiltrating Tregs (P = .02) while increasing the infiltration of CD8+ T cells in TNBC mouse models through the reduction of C-C motif ligand 2 (CCL2). Tumor-associated macrophages were the predominant cells secreting CCL2, and inhibition of JNK signaling reduced CCL2 secretion of human primary macrophages. Moreover, in patients with TNBC (n = 43), those with high levels of CCL2+ tumor-associated macrophages had more Treg and less CD8+ T cell infiltration (P = .04), and the serum CCL2 level was associated with poor overall survival (hazard ratio = 2.65, 95% confidence interval = 1.29 to 5.44, P = .008) in TNBC patients (n = 46). CONCLUSIONS: The JNK/C-JUN/CCL2 axis contributes to TNBC aggressiveness via forming an immunosuppressive TME and can offer novel therapeutic strategies for TNBC.

Nonphosphorylatable PEA15 mutant inhibits epithelial-mesenchymal transition in triple-negative breast cancer partly through the regulation of IL-8 expression.

BACKGROUND: Triple-negative breast cancer (TNBC) is an aggressive breast cancer subtype that lacks targeted therapies. Patients with TNBC have a very poor prognosis because the disease often metastasizes. New treatment approaches addressing drivers of metastasis and tumor growth are crucial to improving patient outcomes. Developing targeted gene therapy is thus a high priority for TNBC patients. PEA15 (phosphoprotein enriched in astrocytes, 15 kDa) is known to bind to ERK, preventing ERK from being translocated to the nucleus and hence blocking its activity. The biological function of PEA15 is tightly regulated by its phosphorylation at Ser104 and Ser116. However, the function and impact of phosphorylation status of PEA15 in the regulation of TNBC metastasis and in epithelial-to-mesenchymal transition (EMT) are not well understood. METHODS: We established stable cell lines overexpressing nonphosphorylatable (PEA15-AA) and phospho-mimetic (PEA15-DD) mutants. To dissect specific cellular mechanisms regulated by PEA15 phosphorylation status, we performed RT-PCR immune and metastasis arrays. In vivo mouse models were used to determine the effects of PEA15 phosphorylation on tumor growth and metastasis. RESULTS: We found that the nonphosphorylatable mutant PEA15-AA prevented formation of mammospheres and expression of EMT markers in vitro and decreased tumor growth and lung metastasis in in vivo experiments when compared to control, PEA15-WT and phosphomimetic PEA15-DD. However, phosphomimetic mutant PEA15-DD promoted migration, mesenchymal marker expression, tumorigenesis, and lung metastasis in the mouse model. PEA15-AA-mediated inhibition of breast cancer cell migratory capacity and tumorigenesis was the partial result of decreased expression of interleukin-8 (IL-8). Further, we identified that expression of IL-8 was possibly mediated through one of the ERK downstream molecules, Ets-1. CONCLUSIONS: Our results show that PEA15 phosphorylation status serves as an important regulator for PEA15's dual role as an oncogene or tumor suppressor and support the potential of PEA15-AA as a therapeutic strategy for treatment of TNBC.

Prostate cancer cells survive anti-androgen and mitochondrial metabolic inhibitors by modulating glycolysis and mitochondrial metabolic activities.

BACKGROUND: Most cancer cells are more glycolytic even under aerobic conditions compared with their normal counterparts. Recent evidence of tumor cell metabolism, however, shows that some tumors also increase mitochondrial oxidative phosphorylation (ox-phos) at some disease states during progression and/or development of drug resistance. Our data show that anti-androgen enzalutamide (ENZA) resistant prostate cancer (PCa) cells use more mitochondrial metabolism leading to higher ox-phos as compared to the ENZA-sensitive cells and can become vulnerable to mitochondrial metabolism targeted therapies. METHODS: Seahorse assay, mass spectrometry and high resolution fluorescence confocal microscopy coupled with image analysis has been used to compare mitochondrial metabolism in ENZA-treated and -untreated anti-androgen-sensitive LNCaP and -resistant C4-2, CWR22ν1, and PCa2b cells. Ex vivo fluorescence microscopy and image analysis has been standardized to monitor mitochondrial electron transport (ETS) activity that likely increases ox-phos in circulating tumor cells (CTCs) isolated fom patients undergoing AR-targeted therapies. RESULTS: Our data show that PCa cells that are resistant to anti-androgen ENZA switch from glycolysis to ox-phos leading to an increased ETS activity. ENZA pretreated cells are more vulnerable to ETS component complex I inhibitor IACS-010759 (IACS) and mitochondrial glutaminase inhibitor CB-839 that reduces glutamate supply to tricarboxylic acid cycle. CTCs isolated from 6 of 20 patient blood samples showed relatively higher ETS activity than the rest of the patients. All six patients have developed ENZA resistance within less than 6 months of the sample collection. CONCLUSION: The enhanced growth inhibitory effects of mitochondrial metabolic inhibitors IACS and CB-839 in ENZA pretreated PCa cells provides a rationale for designing a drug combination trial. Patients can be selected for such trials by monitoring the mitochondrial ETS activities in their CTCs to maximize success.

Enumeration and molecular characterization of circulating tumor cells enriched by microcavity array from stage III non-small cell lung cancer patients.

BACKGROUND: Various methods of liquid biopsy through the sampling of blood in cancer patients allow access to minuscule amounts of tumor that can easily be sampled repeatedly throughout therapy. Circulating tumor cells (CTCs) represent shed tumor cells that can be characterized by imaging or molecular techniques using an amenable enrichment platform. Here we validate the Hitachi Chemical Micro Cavity Array (MCA) for the enrichment of CTCs from the blood of patients diagnosed with stage III non-small cell lung cancer (NSCLC). MCA is a semi-automated filtration system that enriches CTCs on the basis of size and membrane deformability rather than a biased selection of surface antigens. METHODS: CTCs were enriched from the peripheral blood of 38 patients diagnosed with stage III NSCLC at the start of chemoradiation. Two tubes of EDTA blood were collected from each patient and processed through MCA in parallel. In the first tube, CTCs were identified as pan-cytokeratin (CK)+ CD45- nucleated cells and enumerated. The second tube was depleted of leukocytes using CD45 antibody-coated magnetic microbeads before enrichment by MCA, followed by quantitative reverse transcription polymerase chain reaction (qRT-PCR) to interrogate CTC-enriched lysates for expression of 16 target mRNAs from a panel of epithelial, mesenchymal, stem-like, and cancer signaling-related genes. CTC-enriched lysates from similarly prepared peripheral blood samples from 18 healthy donors were used to define positive gene expression. RESULTS: CTCs were identified by imaging in 30 of 38 patient samples (79%). At least 1 target gene was positively expressed in 23 of 25 (92%) patient samples that was subjected to molecular characterization. A CTC count of ≥7 was associated with poor progression-free survival (PFS) [hazard ratio (HR) 4.24, 95% confidence interval (CI), 1.73-10.40, P=0.020] and poor overall survival (HR 8.17, 95% CI, 2.87-23.26, P<0.001). Expression of BCL2 by MCA-enriched CTCs was associated with poor PFS (HR 3.11, 95% CI, 1.18-8.22, P=0.022). Individually, CTC count and expression of BCL2 each remained statistically significant predictors of disease progression and overall survival in multivariate analysis. CONCLUSIONS: This is the first demonstration that lysates of MCA-enriched CTCs are amenable to molecular characterization. CTCs enriched by MCA are an independent prognostic marker in NSCLC.

Antigen-agnostic microfluidics-based circulating tumor cell enrichment and downstream molecular characterization.

Circulating tumor cells (CTC) isolated from the peripheral blood of cancer patients by a minimally invasive procedure provide surrogate markers of the tumor that can be repeatedly sampled. However, the selection and enumeration of CTCs by traditional methods based on surface proteins like EPCAM may not detect CTCs with a mesenchymal phenotype. Here, we employed an antibody-agnostic platform, the Parsortix® PR1 system, which enriches CTCs based on cell size and membrane deformability. We evaluated the linearity, sensitivity, and specificity of the Parsortix PR1 system in tandem with 3 downstream molecular characterization techniques using healthy donor blood spiked with cultured cell lines. Signal amplification of mRNA using a QuantiGene 25-gene assay was able to quantitate multiple epithelial genes, including CDH1, EGFR, ERBB2, KRT18, and MUC1, from high numbers of spiked cells and was able to detect KRT18 when only 50 MCF-7 or SUM190 cells were spiked into healthy donor blood. However, target amplification of mRNA by quantitative polymerase chain reaction (qPCR) showed better sensitivity; qPCR without pre-amplification was able to detect CTC-related genes in Parsortix PR1-enriched cells when as few as 5 SKBR3 cells were spiked into blood. Finally, the HTG EdgeSeq nuclease protection assay was able to profile mRNA expression of over 2,560 cancer-related genes from Parsortix PR1 enriched cells, showing enrichment in cancer signaling pathways and ERBB2, KRT19, and KRT7. Overall, the Parsortix PR1 platform may be amenable to transition into routine clinical workflows.

Use of CAR-Transduced Natural Killer Cells in CD19-Positive Lymphoid Tumors.

BACKGROUND: Anti-CD19 chimeric antigen receptor (CAR) T-cell therapy has shown remarkable clinical efficacy in B-cell cancers. However, CAR T cells can induce substantial toxic effects, and the manufacture of the cells is complex. Natural killer (NK) cells that have been modified to express an anti-CD19 CAR have the potential to overcome these limitations. METHODS: In this phase 1 and 2 trial, we administered HLA-mismatched anti-CD19 CAR-NK cells derived from cord blood to 11 patients with relapsed or refractory CD19-positive cancers (non-Hodgkin's lymphoma or chronic lymphocytic leukemia [CLL]). NK cells were transduced with a retroviral vector expressing genes that encode anti-CD19 CAR, interleukin-15, and inducible caspase 9 as a safety switch. The cells were expanded ex vivo and administered in a single infusion at one of three doses (1×105, 1×106, or 1×107 CAR-NK cells per kilogram of body weight) after lymphodepleting chemotherapy. RESULTS: The administration of CAR-NK cells was not associated with the development of cytokine release syndrome, neurotoxicity, or graft-versus-host disease, and there was no increase in the levels of inflammatory cytokines, including interleukin-6, over baseline. The maximum tolerated dose was not reached. Of the 11 patients who were treated, 8 (73%) had a response; of these patients, 7 (4 with lymphoma and 3 with CLL) had a complete remission, and 1 had remission of the Richter's transformation component but had persistent CLL. Responses were rapid and seen within 30 days after infusion at all dose levels. The infused CAR-NK cells expanded and persisted at low levels for at least 12 months. CONCLUSIONS: Among 11 patients with relapsed or refractory CD19-positive cancers, a majority had a response to treatment with CAR-NK cells without the development of major toxic effects. (Funded by the M.D. Anderson Cancer Center CLL and Lymphoma Moonshot and the National Institutes of Health; ClinicalTrials.gov number, NCT03056339.).

Circulating Tumor Cells: State-of-the-art Update on Technologies and Clinical Applications.

PURPOSE OF REVIEW: Circulating tumor cells represent rare events in the peripheral blood of patients with cancer that can provide insight into tumor biology. CTC enumeration, isolation, and analysis represent liquid biopsy approaches whose role in the management of patients with cancer continues to evolve in the era of precision medicine. This review presents an overview of technologies central to studying CTCs. RECENT FINDINGS: Technologies for CTC isolation can be divided into two categories: label-dependent and label-independent. Label-dependent techniques utilize biological properties such as cell surface proteins, while label-independent techniques utilize distinctive physical properties such as cell size, density, and plasticity. Advances in microfluidics designs as well as hybrid combinations of label-dependent and label-independent techniques have resulted in unprecedented improvements in CTC isolation, permitting not only the detection and enumeration of these rare events but also providing the means for studying them and exploring them as a new dimension of cancer biomarkers. With advances in tools for isolating and studying CTCs in hand, questions regarding the clinical utility of CTC enumeration in peripheral blood, detection of CTC-associated biomarkers, and analysis of dynamic changes in CTCs during the course of cancer therapy represent exciting new opportunities for cancer research.

Elevated serum levels of sialyl Lewis X (sLeX) and inflammatory mediators in patients with breast cancer.

PURPOSE: The carbohydrate sialyl LewisX (sLeX) mediates cell adhesion, is critical in the normal function of immune cells, and is frequently over-expressed on cancer cells. We assessed the association, differential levels, and prognostic value of sLeX and inflammatory cytokines/chemokines in breast cancer sera. METHODS: We retrospectively measured sLeX and a panel of cytokines/chemokines in the sera of 26 non-invasive ductal carcinoma in situ (DCIS), 154 invasive non-metastatic breast cancer (non-MBC), 63 metastatic breast cancer (MBC) patients, and 43 healthy controls. Differences in sLeX and inflammatory cytokines among and between patient groups and healthy controls were assessed with nonparametric tests and we performed survival analysis for the prognostic potential of sLeX using a cut-off of 8 U/mL as previously defined. RESULTS: Median serum sLeX was significantly higher than controls for invasive breast cancer patients (MBC and non-MBC) but not DCIS. In univariate analysis, we confirmed patients with serum sLeX > 8 U/mL have a significantly shorter progression-free survival (PFS) (P = 0.0074) and overall survival (OS (P = 0.0003). Similarly, patients with high serum MCP-1 and IP-10 had shorter OS (P = 0.001 and P < 0.001, respectively) and PFS (P = 0.010 and P < 0.001, respectively). sLeX, MCP-1 and IP-10 remained significant in multivariate survival analysis. CONCLUSION: Elevated serum sLeX was associated with invasive cancer but not DCIS. High serum sLeX levels were associated with inflammatory mediators and may play a role in facilitating local invasion of breast tumor. Furthermore, serum MCP-1, IP-10 and sLeX may have prognostic value in breast cancer.