Prospects for the characterization of habitable planets

With thousands of exoplanets now identified, the characterization of habitable planets and the potential identification of inhabited ones is a major challenge for the coming decades. We review the current working definition of habitable planets, the upcoming observational prospects for their characterization and present an innovative approach to assess habitability and inhabitation. This integrated method couples for the first time the atmosphere and the interior modeling with the biological activity based on ecosystem modeling. We review here the first applications of the method to asses the likelihood and impact of methanogenesis for Enceladus, primitive Earth, and primitive Mars. Informed by these applications for solar system situations where habitability and inhabitation is questionned, we show how the method can be used to inform the design of future space observatories by considering habitability and inhabitation of Earth-like exoplanets around sun-like stars.Comment: 16 pages, 4 figure

Considering the role of adaptive evolution in models of the ocean and climate system

Numerical models have been highly successful in simulating global carbon and nutrient cycles in today's ocean, together with observed spatial and temporal patterns of chlorophyll and plankton biomass at the surface. With this success has come some confidence in projecting the century‐scale response to continuing anthropogenic warming. There is also increasing interest in using such models to understand the role of plankton ecosystems in past oceans. However, today's marine environment is the product of billions of years of continual evolution—a process that continues today. In this paper, we address the questions of whether an assumption of species invariance is sufficient, and if not, under what circumstances current model projections might break down. To do this, we first identify the key timescales and questions asked of models. We then review how current marine ecosystem models work and what alternative approaches are available to account for evolution. We argue that for timescales of climate change overlapping with evolutionary timescales, accounting for evolution may to lead to very different projected outcomes regarding the timescales of ecosystem response and associated global biogeochemical cycling. This is particularly the case for past extinction events but may also be true in the future, depending on the eventual degree of anthropogenic disruption. The discipline of building new numerical models that incorporate evolution is also hugely beneficial in itself, as it forces us to question what we know about adaptive evolution, irrespective of its quantitative role in any specific event or environmental changes

Algal plankton turn to hunting to survive and recover from end-Cretaceous impact darkness

The end-Cretaceous bolide impact triggered the devastation of marine ecosystems. However, the specific kill mechanism(s) are still debated, and how primary production subsequently recovered remains elusive. We used marine plankton microfossils and eco-evolutionary modeling to determine strategies for survival and recovery, finding that widespread phagotrophy (prey ingestion) was fundamental to plankton surviving the impact and also for the subsequent reestablishment of primary production. Ecological selectivity points to extreme post-impact light inhibition as the principal kill mechanism, with the marine food chain temporarily reset to a bacteria-dominated state. Subsequently, in a sunlit ocean inhabited by only rare survivor grazers but abundant small prey, it was mixotrophic nutrition (autotrophy and heterotrophy) and increasing cell sizes that enabled the eventual reestablishment of marine food webs some 2 million years later

Algal plankton turn to hunting to survive and recover from end-Cretaceous impact darkness

The end-Cretaceous bolide impact triggered the devastation of marine ecosystems. However, the specific kill mechanism(s) are still debated, and how primary production subsequently recovered remains elusive. We used marine plankton microfossils and eco-evolutionary modeling to determine strategies for survival and recovery, finding that widespread phagotrophy (prey ingestion) was fundamental to plankton surviving the impact and also for the subsequent reestablishment of primary production. Ecological selectivity points to extreme post-impact light inhibition as the principal kill mechanism, with the marine food chain temporarily reset to a bacteria-dominated state. Subsequently, in a sunlit ocean inhabited by only rare survivor grazers but abundant small prey, it was mixotrophic nutrition (autotrophy and heterotrophy) and increasing cell sizes that enabled the eventual reestablishment of marine food webs some 2 million years later

Abstract P3-14-03: PRESAGE : Prospective multicenter feasibility study of fertility preservation before neoadjuvant or adjuvant chemotherapy for breast cancer: Preliminary results

Abstract Background: Breast cancer is the most frequent form of cancer for young women. For these patients, breast cancer is generally more aggressive and chemotherapy is more often needed. Chemotherapy is commonly associated with amenorrhea and a decrease of ovarian reserve depending on the patient's age, agents and dose. There are no guidelines to prevent subfertility for young women on cytotoxic treatments. Embryo, oocyte and ovarian tissue cryopreservation are the three options to preserve fertility. Embryo and oocyte cryopreservation require controlled ovarian stimulation (COS). The use of COS is associated with an increase of estradiol levels. It led to develop protocols using Tamoxifene or Letrozole combined with FSH to protect patients of the potential deleterious effects of the COS. We are currently conducting a study: PRESAGE, the first French prospective multicenter feasibility study of fertility preservation by COS combined with Tamoxifene and oocyte +/- embryo cryopreservation before neoadjuvant (NAC) or adjuvant (AC) chemotherapy for breast cancer. Material and method: Prospective multicenter study for patients of less than 40 years, with a breast cancer for whom a treatment of NAC or AC is indicated and who wish to preserve their fertility. The main objective: To evaluate the feasibility of a COS associating Tamoxifène with FSH followed by an oocyte more and less embryo cryopreservation. The secondary objectives: evaluation of the average deadline prior to the beginning of the chemotherapy, the impact of the type of COS (depending on the phase of the menstrual cycle, conventional-start or random-start COS protocol) on the number and the quality of oocytes harvested. Statistical analysis was performed using BiostaTGV software. Results: The 50 first patients were included between February 2014 and May 2016. Mean age of the patients was 31 years, half of it was nulliparous (25/50) and 20 % (10/50) were single. They presented mainly SBR II (23/50, 46 %) or III (25/50, 50 %) lesions, ER + (34/50, 68 %). 13 patients benefited from a NAC and 37 of an AC. In the NAC group, the time between the first oncologist's consultation and the fertility specialist's consultation was 3,5 +/- 3,9 days and the time between the first oncologist's consultation and the beginning of the chemotherapy was 24,5 +/- 6 days. The success rate of the COS procedure was 88 % (44/50) with no significant difference between the groups according to the type of COS (conventional-start vs. random-start p = 0.61) but there was a significant difference according to the type of chemotherapy (AC vs. NAC p= 0,03). In the 44 patients who had oocyte retrieval, the number of oocytes was 11,6 +/- 6,3 and an IVF was performed with 11,3% of patients (5/44) with 5,4 +/- 4,6 embryos obtained. We have found no impact of the type of chemotherapy or the type of COS on the number of oocytes or embryos preserved. Conclusion: with an 88% success rate, our study suggests that COS with Tamoxifene and FSH is feasible before adjuvant or neoadjuvant chemotherapy with less success in this context but without any impact on the number of oocytes collected. We hope that these preliminary results will be confirmed at the end of the study. Citation Format: Bordes V, Frick C, Leperlier F, Dezellus A, De Blay P, Maigne F, Sauterey B, Augereau P, Lefeuvre-Plesse C, Campone M, Mirallie S. PRESAGE : Prospective multicenter feasibility study of fertility preservation before neoadjuvant or adjuvant chemotherapy for breast cancer: Preliminary results [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P3-14-03.</jats:p

Characteristics, treatment patterns and survival of patients with high-risk early hormone receptor-positive breast cancer in French real-world settings: an exploratory study of the CANTO cohort

International audienceBackground: Patients with hormone receptor-positive, human epidermal growth factor receptor 2 (HER2)-negative breast cancer (HR+ BC) with unfavorable features have an increased risk of relapse and are currently candidate for additional treatment strategies. We evaluated the real-world clinicopathological characteristics, treatment patterns and survival outcomes of these patients within the CANcer TOxicities study (CANTO, NCT01993498). Patients and methods: This is a retrospective analysis of the prospective data collected within CANTO between 2012 and 2022. Patients with high-risk HR+ BC were defined either by the identification of at least four positive axillary lymph nodes (LNs) or one to three positive axillary LNs with a tumor size ≥5 cm or histologic grade 3 (cohort 1). The definition 1-3 positive LNs with Ki-67 ≥20% was also considered (cohort 2). The Kaplanu2013Meier method was used for survival analysis. Results: Patients with high-risk HR+ BC represented 15.0%-19.6% of HR+ BC (cohort 1 and 2, respectively) in the CANTO cohort. Of the 1266 patients in cohort 1, 617 patients (49.0%) had ≥4 LNs, 327 (26.0%) had tumor ≥5 cm and 727 (57.6%) had grade III tumors. 79.9% had a favorable Charlson comorbidity score and 88.1% stage II/IIIA. Patients with ≥10 LNs accounted for 11.8%. (Neo)adjuvant chemotherapy was administered in 94.2%. Endocrine therapy was prescribed in 97.3%, mostly with aromatase inhibitors and discontinued in 34.3%, mainly for adverse events. Patients enrolled at least 6 years before data extraction had a 5-year invasive disease-free survival and 5-year distant relapse-free survival of 79.9% [95% confidence interval (CI) 77.2% to 82.4%] and 83.5% (95% CI 80.9% to 85.7%), respectively. Conclusions: This real-world study confirms that patients with HR+ BC and unfavorable clinicopathological features are at risk of relapse early in their adjuvant treatment trajectory, despite (neo)adjuvant chemotherapy. It is imperative to implement innovative treatment approaches for high-risk patients, ideally adding them as early as possible to the adjuvant treatment

166P Metabolomic prediction of breast cancer treatment toxicities

International audienc

Use of tamoxifene-controlled ovarian hyperstimulation for fertility preservation before breast cancer treatment: A prospective cohort study with a 5-year follow-up

International audienc