ILC2-modulated T cell-to-MDSC balance is associated with bladder cancer recurrence.

Non-muscle-invasive bladder cancer (NMIBC) is a highly recurrent tumor despite intravesical immunotherapy instillation with the bacillus Calmette-Guérin (BCG) vaccine. In a prospective longitudinal study, we took advantage of BCG instillations, which increase local immune infiltration, to characterize immune cell populations in the urine of patients with NMIBC as a surrogate for the bladder tumor microenvironment. We observed an infiltration of neutrophils, T cells, monocytic myeloid-derived suppressor cells (M-MDSCs), and group 2 innate lymphoid cells (ILC2). Notably, patients with a T cell-to-MDSC ratio of less than 1 showed dramatically lower recurrence-free survival than did patients with a ratio of greater than 1. Analysis of early and later time points indicated that this patient dichotomy existed prior to BCG treatment. ILC2 frequency was associated with detectable IL-13 in the urine and correlated with the level of recruited M-MDSCs, which highly expressed IL-13 receptor α1. In vitro, ILC2 were increased and potently expressed IL-13 in the presence of BCG or tumor cells. IL-13 induced the preferential recruitment and suppressive function of monocytes. Thus, the T cell-to-MDSC balance, associated with a skewing toward type 2 immunity, may predict bladder tumor recurrence and influence the mortality of patients with muscle-invasive cancer. Moreover, these results underline the ILC2/IL-13 axis as a targetable pathway to curtail the M-MDSC compartment and improve bladder cancer treatment

Implication of CD4+CD8+ double positive T cells in uroiogical cancers

Le système immunitaire joue un rôle central dans le contrôle de la croissance tumorale. En effet, une importante infiltration immunitaire du milieu tumoral est généralement associée à un pronostic favorable. Toutefois, il a été démontré qu'en fonction du microenvironnement tumoral, les cellules immunitaires peuvent avoir une activité anti-tumorale ou pro-tumorale. Dans cette étude, nous nous sommes intéressés à une catégorie de cellules immunitaires, les lymphocytes T. Il existe deux types majeurs de lymphocytes T en fonction de l'expression des corécepteurs CD8 et CD4 à leur surface. Les cellules T CD8+ sont associées à un pronostic favorable du cancer. En effet, elles sont capables de tue directement les cellules tumorales. Les lymphocytes T CD4+ sont des cellules auxiliaires (helper) qui peuvent se différentier en sous- populations T CD4+ Th1 ou Th2. Les cellules Th1 sont favorables dans un contexte oncologique, car elles favorisent le développement d'une réponse dite cellulaire, c'est-à-dire le recrutement et l'activation de lymphocytes T CD8+ cytotoxiques au sein de la tumeur. A l'inverse, les cellules Th- contribuent à la génération d'une réponse dite humorale (production d'anticorps par les lymphocytes B) et inhibent la réponse Th1, raison pour laquelle elles sont plus souvent associées à un mauvais pronostic. Une autre catégorie de cellules T a récemment été mise en évidence, les lymphocytes T CD4+CD8+ double positifs (DP). Ces cellules peuvent être subdivisées en fonction de l'intensité d'expression du CD4 et du CD8, mais aussi selon l'expression de la sous-unité ou du CD8. Jusqu à aujourd'hui, les lymphocytes T DP ont peu été étudiés, bien qu'ils soient déjà décrits dans les cancers avec des données contradictoires sur leur rôle, ce qui suggère une certaine hétérogénéité de leurs fonctions. Dans cette étude, nous avons quantifié les lymphocytes T DP dans le sang de 114 patients atteints d'un cancer urologique (vessie n=54, prostate n=31, rein n=29 et avons caractérisé leur phénotype et leur fonction. Les données ont été comparées à celles de 24 donneurs sains. L'analyse a été faite à l'aide de la cytométrie de flux 10 couleurs. Par rapport aux donneurs sains, le pourcentage des cellules T DP est plus élevé chez les patients, ce qui a pu être attribué à l'augmentation de la fréquence des deux sous-populations de cellules T DP : les CD4highCD8low et CD4+CD8high. Il est à noter que la plupart des cellules T CD4highCD8low DP présentent un phénotype CD8, alors que les cellules CD4+CD8high expriment à la fois les sous-unités CD84 et CD85. D'un point de vue fonctionnel, l'analyse a été effectuée grâce à la génération ex vivo de clones de lymphocytes T DP à partir d'échantillons de sang de donneurs sains et de patients. Nous avons mis en évidence que le phénotype des lymphocytes T DP des patients était biaisé vers un phénotype de cellule mémoire effectrice, avec une production de cytokines Th2 augmentée. En outre, différentes expériences in vitro ont montré que les lymphocytes T DP CD8 et CD8, du fait de leur forte capacité de sécrétion de cytokines de type Th2, sont capables de polariser des cellules T CD4 naïves (Th0) rs un profil Th2, tout en limitant l'induction de cellules Th1. En conclusion, dans un contexte oncologique, nos résultats mettent en évidence un mécanisme immuno-régulateu précédemment non reconnu impliquant les cellules DP T CD4+CD8+, qui dans les cancers urologiques voient leurs taux mais aussi leurs capacités immunorégulatrices augmentés. -- The immune system plays a central role in cancer development, showing both anti-tumor and pro-tumor activities depending on the immune cell subsets and the disease context. While CD8 T cells are associated with a favorable outcome in most cancers, only T helper type 1 (Th1) CD4 T cells play a protective role, in contrast to Th2 CD4 T cells. Double positive (DP) CD4+CD8+ T cells remain understudied, although they were already described in human cancers, with conflicting data regarding their role. Here, we quantified and phenotypically/functionally characterized DP T cells in blood from urological cancer patients. We analyzed blood leukocytes of 24 healthy donors (HD) and 114 patients with urological cancers, including bladder (n = 54), prostate (n = 31), and kidney (n = 29) cancer patients using 10-color flow cytometry. As compared to HD, levels of circulating DP T cells were elevated in all urological cancer patients, which could be attributed to increased frequencies of both CD4highCD8low and CD4+CD8high DP T-cell subsets. Of note, most CD4highCD8low DP T cells show a CD8αα phenotype, whereas CD4+CD8high cells express both CD8α and CD8β subunits. Functional properties were investigated using ex-vivo generated DP T-cell clones. DP T cells from patients were skewed toward an effector memory phenotype, along with enhanced Th2 cytokine production. Interestingly, both CD8αα and CD8αβ DP T cells were able to trigger Th2 polarization of naïve CD4 T cells, while restraining Th1 induction. Thus, these data highlight a previously unrecognized immunoregulatory mechanism involving DP CD4+CD8+ T cells in urological cancers

Respiratory Complications after Cystectomy with Urinary Diversion: Avoidable Complications or Ineluctable Destiny?

Background: Cystectomy with urinary diversion (CUD) is a highly morbid surgery. Despite implementing an enhanced recovery after surgery (ERAS®) protocol, postoperative respiratory complications (PRC) within 30 days after surgery remain frequent. This study aims to identify patients at higher risk of developing PRC after CUD. Methods: We conducted a retrospective analysis of 242 patients who underwent CUD at Lausanne University Hospital from 2012 to 2022, adhering to ERAS® guidelines. Data on postoperative complications, including pneumonia, respiratory failure, pulmonary embolism, lobar atelectasis, and pleural effusion, were analyzed. Chi-square and Mann-Whitney U tests compared patients with and without PRC. A multivariable Cox model identified independent prognostic factors. Results: PRC occurred in 41 patients (17%). Those with PRC experienced longer hospital stays and higher 30-day mortality rates. Poor ERAS® compliance was a significant risk factor. Multivariable analysis showed pneumonia was associated with postoperative ileus, while pulmonary embolism correlated with infectious and cardiovascular complications. Conclusions: PRC result in extended hospitalization and decreased survival. Rigorous adherence to ERAS® protocols, including early mobilization, respiratory physiotherapy, and avoiding nasogastric tubes, is essential for preventing PRC

Tumour-derived PGD2 and NKp30-B7H6 engagement drives an immunosuppressive ILC2-MDSC axis

Group 2 innate lymphoid cells (ILC2s) are involved in human diseases, such as allergy, atopic dermatitis and nasal polyposis, but their function in human cancer remains unclear. Here we show that, in acute promyelocytic leukaemia (APL), ILC2s are increased and hyper-activated through the interaction of CRTH2 and NKp30 with elevated tumour-derived PGD2 and B7H6, respectively. ILC2s, in turn, activate monocytic myeloid-derived suppressor cells (M-MDSCs) via IL-13 secretion. Upon treating APL with all-trans retinoic acid and achieving complete remission, the levels of PGD2, NKp30, ILC2s, IL-13 and M-MDSCs are restored. Similarly, disruption of this tumour immunosuppressive axis by specifically blocking PGD2, IL-13 and NKp30 partially restores ILC2 and M-MDSC levels and results in increased survival. Thus, using APL as a model, we uncover a tolerogenic pathway that may represent a relevant immunosuppressive, therapeutic targetable, mechanism operating in various human tumour types, as supported by our observations in prostate cancer.Group 2 innate lymphoid cells (ILC2s) modulate inflammatory and allergic responses, but their function in cancer immunity is still unclear. Here the authors show that, in acute promyelocytic leukaemia, tumour-activated ILC2s secrete IL-13 to induce myeloid-derived suppressor cells and support tumour growth

Intravesical Ty21a Treatment of Non-muscle-invasive Bladder Cancer Shows a Good Safety Profile.

Standard-of-care immunotherapy for non-muscle-invasive bladder cancer (NMIBC) with intravesical Bacillus Calmettte-Guérin (BCG) is associated with adverse events (AEs), disease recurrence/progression, and supply shortages. Preclinical data have shown that intravesical instillation of Ty21a/Vivotif, the oral vaccine against typhoid fever, may be an effective and safer alternative to BCG. We assessed the safety of intravesical Ty21a in NMIBC. For ethical reasons, patients with low- or intermediate-risk NMIBC not requiring BCG immunotherapy were enrolled. To determine the maximum tolerated dose, escalating doses of Ty21a/Vivotif were intravesically instilled in three patients once a week for 4 wk in phase 1a. In phase 1b, ten patients received the selected dose (1 × 10 <sup>8</sup> CFU) once a week for 6 wk, as for standard BCG therapy. At this dose, all patients completed their treatment. Most patients experienced minor systemic AEs, while half reported mild local bladder AEs. AEs only occurred after one or two instillations for 40% of the patients. Ty21a bacteria were only recovered in three out of 72 urinary samples at 1 wk after instillation. Intravesical Ty21a might be well tolerated with no cumulative side effects, no fever >39 °C, and lower risk of bacterial persistence than with BCG. Ty21a treatment thus warrants clinical trials to explore its safety and antitumor efficacy in high-risk NMIBC. This trial is registered on ClinicalTrials.gov as NCT03421236. We examined the safety of a new intra-bladder immunotherapy for non-muscle-invasive bladder cancer as an alternative to the standard BCG treatment. Our data show that the Ty21a vaccine might be well tolerated. Further studies are needed to determine the safety and antitumor efficacy of this treatment

Tumour-derived PGD2 and NKp30-B7H6 engagement drives an immunosuppressive ILC2-MDSC axis

Group 2 innate lymphoid cells (ILC2s) are involved in human diseases, such as allergy, atopic dermatitis and nasal polyposis, but their function in human cancer remains unclear. Here we show that, in acute promyelocytic leukaemia (APL), ILC2s are increased and hyper-activated through the interaction of CRTH2 and NKp30 with elevated tumour-derived PGD2 and B7H6, respectively. ILC2s, in turn, activate monocytic myeloid-derived suppressor cells (M-MDSCs) via IL-13 secretion. Upon treating APL with all-trans retinoic acid and achieving complete remission, the levels of PGD2, NKp30, ILC2s, IL-13 and M-MDSCs are restored. Similarly, disruption of this tumour immunosuppressive axis by specifically blocking PGD2, IL-13 and NKp30 partially restores ILC2 and M-MDSC levels and results in increased survival. Thus, using APL as a model, we uncover a tolerogenic pathway that may represent a relevant immunosuppressive, therapeutic targetable, mechanism operating in various human tumour types, as supported by our observations in prostate cancer