Some of the anti-neoplastic effects of anthracyclines in mice originate from the induction of innate and T cell-mediated anticancer immune responses. Here we demonstrate that anthracyclines stimulate ...the rapid production of type I interferons (IFNs) by malignant cells after activation of the endosomal pattern recognition receptor Toll-like receptor 3 (TLR3). By binding to IFN-α and IFN-β receptors (IFNARs) on neoplastic cells, type I IFNs trigger autocrine and paracrine circuitries that result in the release of chemokine (C-X-C motif) ligand 10 (CXCL10). Tumors lacking Tlr3 or Ifnar failed to respond to chemotherapy unless type I IFN or Cxcl10, respectively, was artificially supplied. Moreover, a type I IFN-related signature predicted clinical responses to anthracycline-based chemotherapy in several independent cohorts of patients with breast carcinoma characterized by poor prognosis. Our data suggest that anthracycline-mediated immune responses mimic those induced by viral pathogens. We surmise that such 'viral mimicry' constitutes a hallmark of successful chemotherapy.
No study has evaluated the predictive and prognostic role of CD8 and PD-L1 coexpression in non-small-cell lung cancer (NSCLC).
We analyzed RNA sequencing and/or immunohistochemistry staining in NSCLC ...patients from The Cancer Genome Atlas (n = 1016), and 34 metastatic NSCLC samples not treated by immunotherapy as prognostic cohorts. As predictive aspect of CD8 and PD-L1, we used 85 NSCLC patients treated with anti-PD-1. Two validation cohorts were used including 44 NSCLC patients treated with anti-PD-1 and an external cohort with different tumor types.
In prognostic cohorts, high CD8A expression was associated with longer OS (p = 0.02), while high CD274 mRNA was associated with poor prognosis (p = 0.05). In predictive cohort, high CD8 expression and CD8A mRNA were associated with longer progression-free survival (PFS) (p = 0.0002). There was no significant association between PD-L1 expression and PFS while high CD274 mRNA was associated with longer PFS (p = 0.009). A combination of CD8A and CD274 was highly predictive of outcome. These results were confirmed in the validation cohorts. This two-genes signature demonstrated similar results compared to gold standard signatures.
CD8 represents both a prognostic and predictive factor of outcomes, while PD-L1 share different prognostic and predictive roles.
In the era of immunotherapies there is an urgent need to implement the use of circulating biomarkers in clinical practice to facilitate personalized therapy and to predict treatment response. We ...conducted a prospective study to evaluate the usefulness of circulating exosomal-PD-L1 in melanoma patients' follow-up. We studied the dynamics of exosomal-PD-L1 from 100 melanoma patients by using an enzyme-linked immunosorbent assay. We found that PD-L1 was secreted through exosomes by melanoma cells. Exosomes carrying PD-L1 had immunosuppressive properties since they were as efficient as the cancer cell from which they derive at inhibiting T-cell activation. In plasma from melanoma patients, the level of PD-L1 (n= 30, median 64.26 pg/mL) was significantly higher in exosomes compared to soluble PD-L1 (n= 30, 0.1 pg/mL). Furthermore, exosomal-PD-L1 was detected in all patients whereas only 67% of tumour biopsies were PD-L1 positive. Although baseline exosomal-PD-L1 levels were not associated with clinic-pathologic characteristics, their variations after the cures (ΔExoPD-L1) correlated with the tumour response to treatment. A ΔExoPD-L1 cut-off of> 100 was defined, yielding an 83% sensitivity, a 70% specificity, a 91% positive predictive value and 54% negative predictive values for disease progression. The use of the cut-off allowed stratification in two groups of patients statistically different concerning overall survival and progression-free survival. PD-L1 levels in circulating exosomes seem to be a more reliable marker than PD-L1 expression in tumour biopsies. Monitoring of circulating exosomal-PD-L1 may be useful to predict the tumour response to treatment and clinical outcome.
Objective
Chronically demyelinated multiple sclerosis (MS) lesions are frequently characterized by scarce undifferentiated oligodendrocyte progenitor cells (OPCs), suggesting the exhaustion of a ...local OPC pool followed by failure of recruitment and differentiation. Stimulating prompt OPC recruitment following demyelination could improve myelin repair by providing sufficient numbers of remyelinating cells during the repair‐permissive period. Understanding mechanisms that determine this process may have important therapeutic implications. We therefore investigated the role of the guidance molecule netrin‐1 in OPC recruitment and central nervous system (CNS) remyelination.
Methods
Netrin‐1 expression was analyzed immunohistochemically in different types of MS lesions and in the murine lysolecithin model of demyelination. The influence of netrin‐1 on CNS remyelination was examined using gain and loss of function experiments.
Results
We show that in MS lesions, astrocytes upregulate netrin‐1 expression early during demyelination and netrin‐1 receptors are expressed by OPCs. In contrast, in the efficiently repairing lysolecithin model of demyelination (astrocyte‐free), netrin‐1 expression is absent during early phases and detected concomitant with completion of OPC recruitment. In vitro migration assays demonstrated that netrin‐1 is a chemorepellent for migrating adult OPCs. In mouse lesions, antibody‐mediated disruption of netrin‐1 function at the peak phase of recruitment increased OPC numbers. Conversely, lentiviral‐mediated induction of netrin‐1 expression prior to OPC recruitment reduced the number of cells recruited and impaired remyelination.
Interpretation
Our findings support the conclusion that netrin‐1 expression within demyelinating MS plaques blocks OPC recruitment, which with repeated demyelinating episodes contributes to permanent remyelination failure. Ann Neurol 2014;76:252–268
T-cell infiltration is associated with good tumor prognosis in many cancers. To assess the capacity of neoadjuvant chemotherapy to affect T-cell infiltration in breast cancer, we evaluated CD3 and ...CD8 infiltrates, and the Foxp3 immunosuppressive T cells.
CD3+, CD8+, and Foxp3+ cell infiltrates were detected by immunohistochemistry in a series of 56 breast cancer patients before and after the end of neoadjuvant chemotherapy.
Poor prognostic factors (negative hormonal receptors, high tumor grade, and nodal involvement) were associated with a significantly higher number of CD3, CD8, and Foxp3 infiltrates before the beginning of chemotherapy. Chemotherapy resulted in a decrease in Foxp3 infiltrates, whereas the level of CD8 and CD3 infiltrates remained unchanged. Pathologic complete responses (pCR) had a drastic decrease of Foxp3+ cells, whereas these cells remained elevated in nonresponders. A cutoff criterion that combined high CD8 infiltration and no Foxp3 cell infiltration on surgical specimens is associated with pCR with a sensitivity of 75% and a specificity of 93%. The infiltrate of cytotoxic TiA1 and granzyme B-positive cells was dramatically enhanced after chemotherapy only in patients with pCR. By multivariate analysis, association of a high CD8 infiltration and no Foxp3 infiltration on final histologic specimens were independently associated with pCR.
These findings indicate that pCR to neoadjuvant chemotherapy is associated with an immunologic profile combining the absence of immunosuppressive Foxp3 cells and the presence of a high number of CD8 T cells and cytotoxic cells. These results argue for the induction of an antitumor immune response by chemotherapy.
There is little data concerning the implications of PIK3CA mutations outside of the known hotspots described in ER+/HER2- metastatic breast cancer (mBC). Similarly, PIK3R1 mutations could also lead ...to activation of PI3K pathway, but are poorly described. We determined the incidence and type of all somatic PIK3CA and PIK3R1 mutations by whole exome sequencing (WES) in a pan-cancer cohort of 1200 patients. Activation of the PI3K pathway was studied using phospho-AKT immunohistochemistry. Associations between PIK3CA/PIK3R1 mutations and response to chemotherapy were studied in mBC cases. We found 141 patients (11.8%) with a PIK3CA and/or PIK3R1 mutation across 20 different cancer types. The main cancer subtype was mBC (45.4%). Eighty-four mutations (62.2%) occurred in the three described hotspots; 51 mutations occurred outside of these hotspots. In total, 78.4% were considered activating or probably activating. Among PIK3R1 mutations, 20% were loss of function mutations, leading to a constitutional activation of the pathway. Phospho-AKT quantification in tumor samples was in favor of activation of the PI3K pathway in the majority of mutated tumors, regardless of mutation type. In ER+/HER2- mBC, first line chemotherapy efficacy was similar for PIK3CA-mutated and PIK3CA-WT tumors, whereas in triple negative mBC, chemotherapy appeared to be more effective in PIK3CA-WT tumors. In this large, real-life pan-cancer patient cohort, our results indicate that PIK3CA/PIK3R1 mutations are widely spread, and plead in favour of evaluating the efficacy of PI3K inhibitors outside of ER+/HER2- mBC and outside of hotspot mutations.
The detection of tumour gene mutations by DNA or RNA sequencing is crucial for the prescription of effective targeted therapies. Recent developments showed promising results for tumoral mutational ...status prediction using new deep learning based methods on histopathological images. However, it is still unknown whether these methods can be useful aside from sequencing methods for efficient population diagnosis. In this retrospective study, we use a standard prediction pipeline based on a convolutional neural network for the detection of cancer driver genomic alterations in The Cancer Genome Atlas (TCGA) breast (BRCA, n = 719), lung (LUAD, n = 541) and colon (COAD, n = 459) cancer datasets. We propose 3 diagnostic strategies using deep learning methods as first-line diagnostic tools. Focusing on cancer driver genes such as KRAS, EGFR or TP53, we show that these methods help reduce DNA sequencing by up to 49.9% with a high sensitivity (95%). In a context of limited resources, these methods increase sensitivity up to 69.8% at a 30% capacity of DNA sequencing tests, up to 85.1% at a 50% capacity, and up to 91.8% at a 70% capacity. These methods can also be used to prioritize patients with a positive predictive value up to 90.6% in the 10% patient most at risk of being mutated. Limitations of this study include the lack of external validation on non-TCGA data, dependence on prevalence of mutations in datasets, and use of a standard DL method on a limited dataset. Future studies using state-of-the-art methods and larger datasets are needed for better evaluation and clinical implementation.
HER2-positive breast cancer has long proven to be a clinically distinct class of breast cancers for which several targeted therapies are now available. However, resistance to the treatment associated ...with specific gene expressions or mutations has been observed, revealing the underlying diversity of these cancers. Therefore, understanding the full extent of the HER2-positive disease heterogeneity still remains challenging. Here we carry out an in-depth genomic characterization of 64 HER2-positive breast tumour genomes that exhibit four subgroups, based on the expression data, with distinctive genomic features in terms of somatic mutations, copy-number changes or structural variations. The results suggest that, despite being clinically defined by a specific gene amplification, HER2-positive tumours melt into the whole luminal-basal breast cancer spectrum rather than standing apart. The results also lead to a refined ERBB2 amplicon of 106 kb and show that several cases of amplifications are compatible with a breakage-fusion-bridge mechanism.
Clinicians can use biomarkers to guide therapeutic decisions in estrogen receptor positive (ER+) breast cancer. One such biomarker is cellular proliferation as evaluated by Ki-67. This biomarker has ...been extensively studied and is easily assayed by histopathologists but it is not currently accepted as a standard. This review focuses on its prognostic and predictive value, and on methodological considerations for its measurement and the cut-points used for treatment decision. Data describing study design, patients’ characteristics, methods used and results were extracted from papers published between January 1990 and July 2010. In addition, the studies were assessed using the REMARK tool. Ki-67 is an independent prognostic factor for disease-free survival (HR 1.05–1.72) in multivariate analyses studies using samples from randomized clinical trials with secondary central analysis of the biomarker. The level of evidence (LOE) was judged to be I-B with the recently revised definition of Simon. However, standardization of the techniques and scoring methods are needed for the integration of this biomarker in everyday practice. Ki-67 was not found to be predictive for long-term follow-up after chemotherapy. Nevertheless, high KI-67 was found to be associated with immediate pathological complete response in the neoadjuvant setting, with an LOE of II-B. The REMARK score improved over time (with a range of 6–13/20 vs. 10–18/20, before and after 2005, respectively). KI-67 could be considered as a prognostic biomarker for therapeutic decision. It is assessed with a simple assay that could be standardized. However, international guidelines are needed for routine clinical use.
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