Suchergebnisse

The use of monoclonal antibodies targeting PD-1/PD-L1 axis completely changed anticancer treatment strategies. However, despite the significant improvement in overall survival and progression-free survival of patients undergoing these immunotherapy treatments, the only clinically accepted biomarker with some prediction capabilities for the outcome of the treatment is PD-L1 expression in tumor biopsies. Nevertheless, even when having PD-L1-positive tumors, numerous patients do not respond to these treatments. Considering the high cost of these therapies and the risk of immune-related adverse events during therapy, it is necessary to identify additional biomarkers that would facilitate stratifying patients in potential responders and non-responders before the start of immunotherapies. Here, we review the utility of PD-L1 expression not only in tumor cells but in immune system cells and their influence on the antitumor activity of immune cell subsets. ; The Oncoimmunology group is funded by Asociación Española Contra el Cáncer, (AECC PROYE16001ESCO); Instituto de Salud Carlos III, Spain, (FIS grant PI17/02119); and a 'Precipita' Crowdfunding grant (FECYT), no grant number; Government of Navarre grant (BMED 050-2019); Independent Clinical Research Projects Call (Instituto de Salud Carlos III, Spain; TRANSPOCART); Proyectos estratégicos I+D, Departamento de Industria, Gobierno de Navarra (DESCARTHES).

Introduzione L'asse PD-1/PD-L1 esplica un ruolo chiave nel mantenimento dell'immunotolleranza, come meccanismo base della prevenzione dell'autoimmunità e della preservazione dell'integrità tissutale. L'iperespressione di PD-L1 è stata dimostrata in numerose neoplasie solide, come meccanismo di immunoevasione. Questo ha condotto allo sviluppo di anticorpi specifici anti PD-1/PD-L1, come strategia innovativa di immunoterapia antitumorale, con dati clinici molto promettenti in varie patologie neoplastiche non emopoietiche, a fronte di una scarsità nell'ambito delle neoplasie ematologiche. L'identificazione di marcatori specifici di risposta a queste terapie innovative con elevato potenziale, ma ad alto costo e non scevre da tossicità, risulta cruciale nella selezione dei pazienti che possano realmente beneficiarne. In quest'ottica l'indagine immunoistochimica su biopsie tumorali rappresenta la metodica più utilizzata su cui si è basata sia la determinazione dell'espressione di PD-L1 sia l'approvazione all'impiego clinico dei nuovi farmaci. Scopo dello studio Lo studio si propone di valutare l'espressione immunoistochimica di PD-L1 su campioni di biopsia osteo-midollare (BOM) in pazienti con neoplasie ematologiche mieloidi e linfoidi in diverse fasi di malattia e, data l'assenza di dati in letteratura riguardo all'utilizzo di fissativi diversi dalla formalina, di validare tale reazione in diverso fissativo (B5 e SUSA), oltre a fornire una proposta di score di positività. Inoltre, nella coorte di pazienti con mieloma multiplo è stata analizzata la possibile correlazione tra l'espressione di PD-L1, l'andamento di malattia e la risposta alle terapie standard. Materiali e Metodi Sono stati analizzati 227 campioni di BOM in diverso fissativo (B5; SUSA; occasionalmente Formalina) mediante indagine immunoistochimica al fine di valutare l'espressione di PD-L1, utilizzando due differenti anticorpi monoclonali anti PD-L1 (CD274): PD-L1 (E1L3N®) XP®Rabbit mAb (Cell Signaling technology) e PD-L1 clone 22C3 (monoclonal Mouse Anti-human PD-L1)(Dako). Come controllo positivo sono stati valutati: 2 casi di linfoma di Hodgkin rispettivamente su sezione di BOM e su sezione di linfonodo ed 1 caso di melanoma su preparati citologici di apposizione linfonodale. Come controlli negativi sono stati valutati: 2 casi di plasmocitosi reattiva (con espressione politipica delle catene leggere) rispettivamente in un paziente con AIDS ed in un paziente con polmonite da Legionella; 1 caso di BOM normale, eseguita nel sospetto di patologia linfoproliferativa. La valutazione è stata eseguita collegialmente da due operatori, attribuendo i seguenti score di positività sulla base della percentuale di cellule positive nell'ambito della popolazione neoplastica: 50%. E' stato inoltre fornito un giudizio sull'intensità di espressione (debole o intensa) e il tipo di positività intracellulare (focale, diffusa). I 227 campioni analizzati (c.a.), relativi a 139 pazienti, includono le seguenti neoplasie ematologiche in diverse fasi di malattia: Linfoma a Grandi Cellule Anaplastico CD30+ ALK+ (1 c.a.); Leucemia/Linfoma a cellule T dell'adulto (ATLL) (2 c.a.); Leucemia linfatica cronica B (2 c.a.); Linfoma Diffuso a Grandi Cellule B (11 c.a.); Linfoma Follicolare (5 c.a.); Linfoma Mantellare (1 c.a.); Linfoma Marginale (3 c.a.); Sindrome Mielodisplastica con eccesso di blasti tipo 2 (MDS-EB2) (2 c.a.); Leucemia Mieloide Acuta (47 c.a.) ; Leucemia Linfoblastica acuta B-Ph+ (21 c.a.); Leucemia Linfoblastica B-Ph- (3 c.a.); Leucemia Linfoblastica T (1 c.a.); Mieloma Multiplo (128 c.a.). Di questi ultimi è stata analizzata l'eventuale correlazione tra positività per PD-L1, andamento clinico e risposta a terapia.

The search for non-invasive systemic biomarkers of response to PD-L1/PD-1 blockade immunotherapy is currently a priority in oncoimmunology. In contrast to classical tumor biomarkers, the identification of clinically useful immunological biomarkers is certainly a challenge, as anti-cancer immune responses depend on the coordinated action of many cell types. Studies on the dynamics of systemic CD8 T-cell populations have provided indications that such biomarkers may have a place in clinical practice. However, the power of CD8 T-cell subsets to discriminate clinical responses in immunotherapy has so far proven to be limited. The systemic evaluation of CD8 T-cell regulators such as myeloid cells and CD4 T cells may provide the solution. Here we discuss the value of systemic quantification of CD4 T-cell subsets for patient selection in light of the results obtained by Prof. Kagamu′s and our team. Our studies have independently demonstrated that the evaluation of the pre-treatment status of systemic CD4 immunity is a critical factor for the clinical outcome of PD-L1/PD-1 blockade therapy with robust predictive capacities. ; This work was funded by the Spanish Association against Cancer (AECC, PROYE16001ESCO), Instituto de Salud Carlos III (ISCIII, FIS. PI17/02119), Biomedicine Project grant from the Department of Health of the Government of Navarre (BMED 050-2019), JSPS KAKENHI grant number 17H04184, and the Japan Agency for Medical Research and Development (grant nos. 19ae0101074h0001).

Peña-Asensio, J.; Calvo, H.; Torralba, M.; Miquel, J.; Sanz-de-Villalobos, E.; Larrubia, J.-R. Anti-PD-1/PD-L1 Based Combination Immunotherapy to Boost Antigen-Specific CD8+ T Cell Response in Hepatocellular Carcinoma. Cancers 2021, 13, 1922. ; Thirty to fifty percent of hepatocellular carcinomas (HCC) display an immune class genetic signature. In this type of tumor, HCC-specific CD8 T cells carry out a key role in HCC control. Those potential reactive HCC-specific CD8 T cells recognize either HCC immunogenic neoantigens or aberrantly expressed host's antigens, but they become progressively exhausted or deleted. These cells express the negative immunoregulatory checkpoint programmed cell death protein 1 (PD-1) which impairs T cell receptor signaling by blocking the CD28 positive co-stimulatory signal. The pool of CD8 cells sensitive to anti-PD-1/PD-L1 treatment is the PD-1dim memory-like precursor pool that gives rise to the effector subset involved in HCC control. Due to the epigenetic imprints that are transmitted to the next generation, the effect of PD-1 blockade is transient, and repeated treatments lead to tumor resistance. During long-lasting disease, besides the TCR signaling impairment, T cells develop other failures that should be also set-up to increase T cell reactivity. Therefore, several PD-1 blockade-based combinatory therapies are currently under investigation such as adding antiangiogenics, anti-TGFβ1, blockade of other negative immune checkpoints, or increasing HCC antigen presentation. The effect of these combinations on CD8+ T cells is discussed in this review. ; Instituto de Salud Carlos III ; European Regional Development Fund (ERDF) ; European Union ; Gilead Fellowship Programme

Colorectal cancer (CRC) is a very heterogeneous disease. Efforts to characterize and search for biomarkers for these patients are currently ongoing in the hope of establishing a more targeted therapeutic approach. The role of PD-1 ligand (PD-L1) expression as a biomarker has not yet been fully elucidated. The Consensus Molecular Subtype classification has been delineated, but although already acknowledged in the most recent international guidelines, it has yet to be implemented in clinical practice. We investigate PD-L1 expression as a biomarker of prognosis in the early-stage setting and integrate it with the Consensus Molecular Subtype (CMS), in an effort to differentiate those patients with a worse prognosis who could potentially benefit from an early, more aggressive treatment. Our results suggest PD-L1 as an independent prognostic factor in early stage setting when assessed by immunohistochemistry. Additionally, PD-L1 expression appears to be a viable biomarker to differentiate patients in the CMS (CMS2/CMS3) who lack a clear prognosis. ; This research was partly funded by European Union Regional Development Fund (17-20, RefBioII, Trans-Pyrenean cooperation network program 2016-2018, INTERREG-POCTEFA)

Los tumores escapan eficazmente del ataque inmunitario al inhibir las actividades antitumorales de las células T. Esto se logra mediante al menos dos mecanismos principales. En primer lugar por el establecimiento de interacciones inhibitorias entre T y las células tumorales a través de la unión de "programed death"-1 (PD1) y su ligando (PDL1). En segundo lugar, al inducir la expansión de células mieloides inmunosupresoras potentes (MDSC). En esta tesis doctoral, he estudiado estas dos barreras inmunosupresoras clave para la terapia del cáncer. PDL1 es una de las moléculas inmunorreguladoras más importantes expresadas en la superficie celular de muchos tipos de células, incluidas las cancerosas. Además de unirse al receptor inhibidor PD1 en las células T, suprime las respuestas inmunes a través de vías de señalización intracelulares intrínsecas que mejoran la supervivencia de las células cancerosas, regulan las respuestas al estrés y confieren resistencia frente a estímulos proapoptóticos tales como los interferones. La administración sistémica de anticuerpos que bloquean las interacciones PDL1 / PD1 en pacientes con cáncer está demostrando un éxito clínico sin precedentes, pero aún queda mucho por conocer sobre sus mecanismos de acción. El primer objetivo de esta tesis fue identificar qué motivos en la secuencia dentro del dominio intracitoplásmatico, median la protección mediada por PDL1 frente a la apoptosis inducida por IFN. Se identificaron dos motivos implicados en el suministro de señales que inhiben las rutas de transducción de señales de IFN. Además, se descubrió que los cánceres humanos adquieren mutaciones somáticas dentro de estos motivos que potencian las actividades anti-interferón de PDL1, favoreciendo el crecimiento de células cancerosas in vitro. En general, los resultados presentados en esta tesis doctoral descubren un modo de acción de PDL1 en células cancerosas como primera línea de defensa contra la citotoxicidad de IFN. Las MDSC se diferencian de los precursores de la médula ósea y se expanden en los hospedadores con cáncer. Las MDSC se infiltran en tumores donde ejercen actividades procarcinógenicas. La identificación de vías moleculares específicas en las MDSC podría ayudar al desarrollo de nuevos tratamientos antineoplásicos. El segundo objetivo de esta sección de la tesis consistió en el estudio molecular en profundidad de MDSCs murinas generadas ex vivo que se asemejan a subconjuntos de infiltración de tumores de melanoma mediante proteómica cuantitativa de alto rendimiento. Se comparó el proteoma neoplásico de MDSC con los controles de MDSC no neoplásicos y las células dendríticas (DC) convencionales derivadas de médula ósea. Nuestros análisis dieron como resultado el mapa del interactoma más detallado del MDSC murinas hasta la fecha, y se descubrieron las redes que regulan el linaje celular y las vías inducidas por el cáncer. Proponemos algunas quinasas como dianas terapéuticas específicas de MDSC. Las actividades de estas quinasas regulan diferencialmente la diferenciación y las actividades de las MDSC, y se pueden inhibir específicamente en las MDSC mientras que las DC inmunogénicas no se ven afectadas en gran medida. Finalmente, discuto la potencial combinación de terapias dirigidas a ambas barreras; inhibición de las interacciones PD1-PDL1 y el bloqueo de las actividades de las MDSC como un enfoque óptimo para las terapias contra el cáncer. ; Tumors effectively escape from the immune attack by inhibiting anti-tumor activities of T cells. This is achieved by at least two mechanisms, although there are several others of importance. First, the establishment of inhibitory interactions between T and tumor cells through programmed death-1 (PD-1) binding to its ligand (PD-L1), among others. Second, by inducing the expansion of potent immunosuppressive myeloid-derived suppressor cells (MDSCs). In this Ph.D. thesis, I have studied these two key immunosuppressive barriers for cancer therapy. PD-L1 is one of the most important immunoregulatory molecules expressed on the cell surface of many cell types including cancer cells. Apart from binding to the inhibitory receptor PD-1 on T cells, it suppresses immune responses by the delivery of intrinsic intracellular signaling pathways that enhance cancer cell survival, regulates stress responses and in this thesis we discover that it confers resistance towards pro-apoptotic stimuli such as interferons. The systemic administration of antibodies that block PD-L1/PD-1 interactions to cancer patients is demonstrating unprecedented clinical success, but much is yet to be known on the mechanisms of action. The first aim of this thesis was to firsltly identify sequence motifs within the intracytoplasmic domain of PD-L1 mediating protection from IFN-β-induced apoptosis. Two motifs implicated in the delivery of signals that inhibit IFN-β signal transduction pathways were identified. Moreover, it was found that human cancers acquire somatic mutations within these motifs that enhance the anti-interferon activities of PD-L1, favoring cancer cell growth in vitro. Overall, the results presented in this Ph.D. thesis uncovers a mode of action of PD-L1 in cancer cells as the first line of defense against IFN cytotoxicity. Myeloid derived suppressor cells (MDSCs) differentiate from bone marrow precursors and expand in cancer-bearing hosts. MDSCs infiltrate tumors where they exert pro-carcinogenic activities. Identification of specific molecular pathways in MDSCs could help the development of novel anti- neoplastic treatments. The second aim of this thesis consisted in the in-depth molecular study of ex vivo generated murine MDSCs that resemble melanoma tumor-infiltrating subsets by high-throughput quantitative proteomics. The neoplastic MDSC proteome was compared to those of non-neoplastic MDSC controls (derived ex vivo from 293T conditionant medium), and conventional bone-marrow derived dendritic cells (DCs). Our analyses resulted in the most detailed interactome map of the murine MDSC to date, and uncovered the networks regulating cell lineage and cancer-induced pathways. We propose some kinases as MDSC-specific therapeutic targets. The activities of these kinases differentially regulate MDSC differentiation and activities and can be specifically inhibited in MDSCs while keeping immunogenic DCs largely unaffected. Finally, I discuss the potential combination of therapies targeting both barriers; inhibition of PD-1-PD-L1 interactions and blockade of MDSC activities as an optimal approach for anti-cancer therapies. ; This project was funded by a crowdfunding project by FECYT (PRECIPITA, Spain), a FIS grant (PI14/00579) from the Instituto de Salud Carlos III, a grant from the Government of Navarre (BMED 033-2014, Spain) and a grant from Fundación Caixa (Spain) to GK. The author thanks SARAY foundation (Navarra, Spain) and Sandra Ibarra´s Foundation for their financial support. MG is funded by a PhD fellowship granted by the Government of Navarre. ; Programa de Doctorado en Ciencias de la Salud (RD 99/2011) ; Osasun Zientzietako Doktoretza Programa (ED 99/2011)

Acute myeloid leukemia (AML) is a genetically heterogeneous clonal disease defined by the proliferation and accumulation of immature hematopoietic cells in the bone marrow and blood. This study aimed to evaluate the CD47 and CD274 (PD-L1) expression in Iraqi AML patients and its role in the disease and evasion of malignant cells from immune system. The study was conducted on 85 patients diagnosed with leukemia, 25 of them were excluded as they had taken chemotherapy for less than a week and because the proportion of tumor cells was less than 20%. Virtually, it was conducted on 60 patients with AML and 20 healthy individuals as a control group. The expression of CD47 and CD274 (PD-L1) was evaluated using flow cytometry in the peripheral blood of AML samples only. Also MMP-2 level in serum was evaluated via ELISA in both AML and control samples. The expression of CD47 and CD274 in AML patients was found to be high. Analysis of CD274 (PDL1) expression in blast populations showed a significant increase in the proportion of CD274 (PD-L1) positive blast cells in isolated peripheral blood samples (66.3050 ± 1.94522). Also, the CD47 expression on blast cells in AML was recorded as significantly high (64.9333±2.05873). For MMP-2 (ng/ml) level in serum, the mean level non-significantly increased in AML as compared to the control group (102.677±8.719; 92.191±5.161) respectively.

The expression of PD-L1 protein was quanti ed in 56 samples of urothelial bladder cancer (BC). PD-L1 expression was detected in all BC samples, while in non-muscle-invasive bladder cancer (NMIBC) the median value is 1,5 times higher than in muscle-invasive bladder cancer (MIBC) (p = 0,001). High PD-L1 expression level (≥30%) was observed in 20% of MIBC samples and among NMIBC tumors - in 68% of cases, that is 3,4 times more often (p = 0,0004). The last fact justi es the prospect of starting therapy with immune checkpoint inhibitors already at the onset of the disease - at NMIBC.

Yi Qing,1,* Qing Li,1,* Tao Ren,1 Wei Xia,1 Yu Peng,1 Gao-Lei Liu,2 Hao Luo,1 Yu-Xin Yang,1 Xiao-Yan Dai,1 Shu-Feng Zhou,3 Dong Wang1 1Cancer Center, 2Urological Surgery, Daping Hospital and Research Institute of Surgery, Third Military Medical University, Chongqing, People's Republic of China; 3Department of pharmaceutical Sciences, College of Pharmacy, University of South Florida, Tampa, FL, USA *These authors contributed equally to this work Introduction: Gastric cancer is a fatal malignancy with a rising incidence rate. Effective methods for early diagnosis, monitoring metastasis, and prognosis are currently unavailable for gastric cancer. In this study, we examined the association of programmed death ligand-1 (PD-L1) and apurinic/apyrimidinic endonuclease 1 (APE1) expression with the prognosis of gastric cancer. Methods: The expressions of PD-L1 and APE1 were detected by immunohistochemistry in 107 cases of human gastric carcinoma. The correlation of PD-L1 and APE1 expression with the clinicopathologic features of gastric carcinoma was analyzed by SPSS version 19.0. Results: The positive expression rates of PD-L1 and APE1 in gastric cancer tissues were 50.5% (54/107) and 86.9% (93/107), respectively. PD-L1 and APE1 positive expressions were significantly associated with depth of invasion, lymph node metastasis, pathological type, overall survival, and higher T stage. Furthermore, the expression of PD-L1 in highly differentiated gastric cancers was higher than that in poorly differentiated cancers (P=0.008). Moreover, the expression of APE1 and PD-L1 in gastric cancers was positively correlated (r=0.336, P<0.01). Multivariate analysis showed that the depth of invasion was a significant prognostic factor (risk ratio 19.91; P=0.000), but there was no significant relationship with PD-L1, APE1, prognosis, and other characteristics. Conclusion: The deregulation of PD-L1 and APE1 might contribute to the development and the poor prognosis of gastric cancer. Our findings suggest that high expression of PD-L1 and APE1 is a risk factor of gastric cancer and a new biomarker to predict the prognosis of gastric cancer. Furthermore, our findings suggest that targeting the PD-L1 and APE1 signaling pathways may be a new strategy for cancer immune therapy and targeted therapy for gastric cancer, especially in patients with deep invasion and lymph node metastasis. Keywords: gastric carcinoma, immunohistochemistry, prognostic, potential targets