The diversity of the naïve T cell repertoire drives the replenishment potential and capacity of memory T cells to respond to immune challenges. Attrition of the immune system is associated with an increased prevalence of pathologies in aged individuals, but whether stem cell memory T lymphocytes (T_SCM) contribute to such attrition is still unclear. Using single cells RNA sequencing and high-dimensional flow cytometry, we demonstrate that T_SCM heterogeneity results from differential engagement of Wnt signaling. In humans, aging is associated with the coupled loss of Wnt/β-catenin signature in CD4 T_SCM and systemic increase in the levels of Dickkopf-related protein 1, a natural inhibitor of the Wnt/β-catenin pathway. Functional assays support recent thymic emigrants as the precursors of CD4 T_SCM. Our data thus hint that reversing T_SCM defects by metabolic targeting of the Wnt/β-catenin pathway may be a viable approach to restore and preserve immune homeostasis in the context of immunological history.

Advance care planning is essential to enable informed medical decisions to be made and to reduce aggressiveness in end-of-life (EOL) care. This study aimed to explore whether a question prompt list (QPL) adapted to French language and culture could promote discussions, particularly on prognosis and EOL issues, among advanced cancer patients attending outpatient palliative care (PC) consultations. In this multicenter randomized study, patients assigned to the intervention arm received a QPL to help them prepare for the next consultation one month later. The main inclusion criteria were advanced cancer patients referred to the PC team with an estimated life expectancy of less than one year. The primary endpoint was the number of questions raised, globally and by topic. The secondary objectives were the impact of the QPL on psychological symptoms, quality of life, satisfaction with care, and coping styles at two months. Patients (n = 71) in the QPL arm asked more questions (mean 21.8 vs. 18.2, P = 0.03) than patients in the control arm (n = 71), particularly on PC (5.6 vs. 3.7, P = 0.012) and EOL issues (2.2 vs. 1, P = 0.018) but not on prognosis (4.3 vs. 3.6, not specified). At two months, there was no change in anxiety, depression, or quality of life in either arm; patient satisfaction with doctors' technical skills was scored higher (P = 0.024), and avoidance coping responses were less frequent (self-distraction, P = 0.015; behavioral disengagement, P = 0.025) in the QPL arm. Questions on PC and EOL issues in outpatient PC consultations were more frequent, and patient satisfaction was better when a QPL was made available before the consultation.

Langerhans cell histiocytosis (LCH) is a potentially fatal neoplasm characterized by the aberrant differentiation of mononuclear phagocytes, driven by mitogen-activated protein kinase (MAPK) pathway activation. LCH cells may trigger destructive pathology yet remain in a precarious state finely balanced between apoptosis and survival, supported by a unique inflammatory milieu. The interactions that maintain this state are not well known and may offer targets for intervention. Here, we used single-cell RNA-seq and protein analysis to dissect LCH lesions, assessing LCH cell heterogeneity and comparing LCH cells with normal mononuclear phagocytes within lesions. We found LCH discriminatory signatures pointing to senescence and escape from tumor immune surveillance. We also uncovered two major lineages of LCH with DC2- and DC3/monocyte-like phenotypes and validated them in multiple pathological tissue sites by high-content imaging. Receptor-ligand analyses and lineage tracing in vitro revealed Notch-dependent cooperativity between DC2 and DC3/monocyte lineages during expression of the pathognomonic LCH program. Our results present a convergent dual origin model of LCH with MAPK pathway activation occurring before fate commitment to DC2 and DC3/monocyte lineages and Notch-dependent cooperativity between lineages driving the development of LCH cells.

Objective Treatment of high-grade serous ovarian carcinomas relies on surgery and chemotherapy, potentially followed by bevacizumab and/or poly (ADP-ribose) polymerase inhibitors (PARPi). The modeled CA-125 ELIMination rate constant K (KELIM) is a pragmatic indicator of tumor primary chemosensitivity. Although it is well established that BRCA mutations are associated with platinum sensitivity, the relationship between BRCA status and KELIM score has yet to be elucidated. This study aimed to evaluate the interactions between BRCA and KELIM, and their respective prognostic values. Methods We retrospectively collected data from 743 patients with high-grade serous ovarian carcinomas included in a French nationwide registry (NCT03275298) treated with neoadjuvant platinum-based chemotherapy followed by surgery. We analyzed the interactions between BRCA and KELIM, and their impacts on progression-free survival and overall survival. Results BRCA-mutated (BRCAm) patients had higher standardized KELIM than BRCA-wild type (BRCAwt) tumors (median 1.16 vs 1.06, respectively; p=0.001). The prognostic value of the KELIM score was independent of BRCA in multivariate analyses. KELIM score and BRCA could be combined to define three prognostic groups: (1) an unfavorable prognostic group with both BRCAwt and unfavorable KELIM (median progression-free survival 12.0 months); (2) an intermediate prognostic group with either BRCAm and unfavorable KELIM, or BRCAwt and favorable KELIM (median progression-free survival of 16.0 and 18.8 months, respectively; HR 0.64 compared with the unfavorable group, p<0.001); and (3) a favorable prognostic group with both BRCAm and favorable KELIM (median progression-free survival 28.8 months; HR 0.37 compared with the unfavorable group, p<0.001). Conclusions The KELIM score provides complementary prognostic information with respect to BRCA, and discriminates different prognoses within BRCAm or BRCAwt patients. Patients with both BRCAwt/unfavorable KELIM have a poor prognosis, underscoring the urgent need for novel therapeutic strategies.

Objective Chemotherapy for high-grade serous ovarian cancers in platinum-sensitive relapse includes carboplatin/paclitaxel, carboplatin/gemcitabine, and carboplatin/pegylated liposomal doxorubicin. According to in vitro data, BRCA mutated patients are sensitive to replicative stress agents but BRCA status is not yet used for the choice of chemotherapy at relapse. Our aim was to assess these doublets according to BRCA status in first platinum-sensitive relapse. Methods The ESME ovarian cancer database comprises a multicenter retrospective cohort of patients with ovarian cancer treated in French cancer centers between January 2011 and December 2017. Patients with high-grade serous ovarian cancers at first platinum-sensitive relapse who received one of these doublets were included. The objective was to compare progression-free survival of each chemotherapy doublet according to BRCA status. Results Among the 10 263 patients in the database, 1539 patients had a first platinum-sensitive relapse: 825 BRCA wild type patients (53.6%) and 304 BRCA mutated patients (19.8%) (7 patients had a homologous recombination mutation and BRCA status was unkown for 403 patients). Median progression-free survival was longer in BRCA mutated patients than in BRCA wild type patients when receiving carboplatin/pegylated liposomal doxorubicin without maintenance treatment (15.8 vs 11.8 months; p<0.001). In contrast, we observed no difference in patients treated with carboplatin/paclitaxel (14.6 vs 14.3 months, respectively; p=0.70) or in those treated with carboplatin/gemcitabine (12.0 vs 9.8 months, respectively; p=0.18). In BRCA wild type patients without maintenance, better progression-free survival occurred with carboplatin/paclitaxel (median progression-free survival 14.3 months) than with carboplatin/gemcitabine and carboplatin/pegylated liposomal doxorubicin (9.8 and 11.8 months, respectively; p=0.017). In BRCA mutated patients without maintenance, there was no difference between the three doublets (median progression-free survival of 14.6, 12.0, and 15.8 months with carboplatin/paclitaxel, carboplatin/gemcitabine, and carboplatin/pegylated liposomal doxorubicin, respectively; p=0.40). Conclusion While treatment with carboplatin/paclitaxel, carboplatin/gemcitabine, and carboplatin/pegylated liposomal doxorubicin shows comparable efficacy in BRCA mutated patients, treatment with carboplatin/paclitaxel appears to be more effective than carboplatin/gemcitabine and carboplatin/pegylated liposomal doxorubicin in BRCA wild type patients with high-grade serous ovarian cancers at first platinum-sensitive relapse.