From a voluntary vaccination policy to mandatory vaccination against COVID-19 in cancer patients: an empirical and interdisciplinary study in bioethics.

BACKGROUND: At the start of 2021, oncologists lacked the necessary scientific knowledge to adapt their clinical practices optimally when faced with cancer patients refusing or reluctant to be vaccinated against COVID-19, despite the marked vulnerability of these patients to severe, and even fatal forms of this new viral infectious disease. Oncologists at Foch Hospital were confronted with this phenomenon, which was observed worldwide, in both the general population and the population of cancer patients. METHODS: Between April and November 2021, the Ethics and Oncology Departments of Foch Hospital decided to investigate this subject, through an empirical and interdisciplinary study in bioethics. Our scientific objective was to try to identify and resolve the principal bio-ethical issues, with a view to improving clinical practices in oncology during future major pandemics of this kind, from a highly specific bio-ethical standpoint (= quality of life/survival). We used a mainly qualitative methodological approach based on questionnaires and interviews. RESULTS: In April 2021, 29 cancer patients refused or were reluctant to be vaccinated (5.6%; 29/522). Seventeen of these patients said that making vaccination mandatory would have helped them to accept vaccination. In October 2021, only 10 cancer patients continued to maintain their refusal (1.9%; 10/522). One of the main reasons for the decrease in refusals was probably the introduction of the "pass sanitaire" (health pass) in July 2021, which rendered vaccination indispensable for many activities. However, even this was not sufficient to convince these 10 cancer patients. CONCLUSION: We identified a key bio-ethical issue, which we then tried to resolve: vaccination policy. We characterized a major tension between "the recommendation of anti-COVID-19 vaccination" (a new clinical practice) and "free will" (a moral value), and the duty to "protect each other" (a moral standard). Mandatory vaccination, at least in France, could resolve this tension, with positive effects on quality of life (i.e. happiness), or survival, in cancer patients initially refusing or reluctant to be vaccinated, but only if collective and individual scales are clearly distinguished.

[Clear cell sarcoma or gastrointestinal neuroectodermal tumor (GNET) of the tongue? Case report and review of the literature of an extremely rare tumor localization]. / Sarcome à cellules claires ou tumeur neuroectodermique gastro-intestinale de la langue ? Une observation avec revue de la littérature dans une localisation exceptionnelle.

Clear cells sarcomas (CCS) are exceptionally rare in the tongue, with, to our knowledge, only three previous reports in anglo-saxon literature. Through our case, we will discuss the differential diagnosis of clear cells tumors of the tongue and bring this tumour closer to the newly described entity of the gastrointestinal tract named "clear cells sarcoma-like gastrointestinal (SCCLGI)", recently renamed "gastrointestinal neuroectodermal tumour (GNET)". SCCLGI/GNET share morphological and molecular characteristics with SCC but had until then been observed only in the digestive tract. Our case could be a lingual localization of a SCCLGI/GNET. SCC and SCCLGI/GNET characteristic molecular profil involves EWSR1-ATF1 [t(12; 22) (q13; q12)] and EWSR1-CREB1 [t(2; 22) (q34; q12)] fusion genes, but it is not specific of these tumours.

p210BCR-ABL inhibits SDF-1 chemotactic response via alteration of CXCR4 signaling and down-regulation of CXCR4 expression.

It has been shown that p210(BCR-ABL) significantly impairs CXCR4 signaling. We report here that the migratory response to SDF-1 was profoundly altered in blast crisis, whereas chronic-phase CD34(+) cells migrated normally to this chemokine. This migratory defect was associated with a low CXCR4 membrane expression. In vitro STI-571 treatment of CD34(+) cells from patients in blast crisis markedly increased the CXCR4 transcript and CXCR4 membrane expression. Because p210(BCR-ABL) frequently increases with disease progression, we determined the effects of high and low p210(BCR-ABL) expression on CXCR4 protein in the granulocyte macrophage colony-stimulating factor-dependent human cell line MO7e. p210(BCR-ABL) expression distinctly alters CXCR4 protein through two different mechanisms depending on its expression level. At low expression, a signaling defect was detected with no modification of CXCR4 expression. However, higher p210(BCR-ABL) expression induced a marked down-regulation of CXCR4 that is related to its decreased transcription. The effect of p210(BCR-ABL) required its tyrosine kinase activity. Collectively, these data indicate that p210(BCR-ABL) could affect CXCR4 by more than one mechanism and suggest that down-regulation of CXCR4 may have important implications in chronic myelogenous leukemia pathogenesis.

[Physiopathology, diagnosis and treatment of breast cancer]. / Physiopathologie, diagnostic et thérapeutique du cancer du sein.

The organised screening of breast cancer, the identification of the type of lesion and the staging determine the treatment plan for this disease. The most common cancer to affect women in France and in Europe, it represents 1/3 of cancers in women and 1/4 of all cancers.

Reduced retention of radioprotective hematopoietic cells within the bone marrow microenvironment in CXCR4-/- chimeric mice.

The physiologic role of CXCR4 on hematopoietic stem/progenitor cells (HSPCs) is not fully understood. Here, we show that radioprotection of lethally irradiated mice by embryonic day 14.5 (E14.5) CXCR4-/- fetal liver (FL) cells was markedly impaired when compared with CXCR4+/+ counterparts, but this defect was rescued when hosts were engrafted with high cell numbers. This quantitative defect contrasted with a similar content in hematopoietic colony-forming cells (CFCs), splenic colony-forming units (CFUs-S), and Lin- Sca-1+ c-kit+ cells in E14.5 CXCR4-/- and CXCR4+/+ livers. In addition, the homing of HSPCs in the bone marrow was not altered as detected with a CFSE-staining assay. In contrast, a 30-fold increase in CFCs was seen in the circulation of mice stably reconstituted with CXCR4-/- FL cells and this increment was already observed before hematopoiesis had reached a steady-state level. Together, the data strongly suggest that impaired retention may, at least in short-term hematopoietic reconstitution, lead to a diminution in the number of available progenitors required for radioprotection.

Randomized phase III trial of topotecan following carboplatin and paclitaxel in first-line treatment of advanced ovarian cancer: a gynecologic cancer intergroup trial of the AGO-OVAR and GINECO.

BACKGROUND: The combination of carboplatin and paclitaxel is the standard of care for the treatment of ovarian cancer, yet rates of recurrence and death remain high. We performed a prospective randomized phase III study to examine whether sequential administration of topotecan can improve the efficacy of carboplatin and paclitaxel in first-line treatment of advanced epithelial ovarian cancer. METHODS: A total of 1308 patients with previously untreated ovarian cancer (International Federation of Gynecology and Obstetrics stages IIB-IV) were randomly assigned to receive six cycles of paclitaxel and carboplatin followed by either four cycles of topotecan (TC-Top; 658 patients) or surveillance (TC; 650 patients) on a 3-week per cycle schedule. The primary endpoint was overall survival, and secondary endpoints were progression-free survival, response rate, toxicity, and quality of life. Time-to-event data were analyzed using the Kaplan-Meier method, and a stratified log-rank test was used to compare distributions between treatment groups. Hazard ratios (HRs) with 95% confidence intervals (CIs) were estimated using a Cox proportional hazards model. Categorical data were compared using a stratified Cochran-Mantel-Haenszel test. All statistical tests were two-sided. RESULTS: Median progression-free survival was 18.2 months in the TC-Top arm versus 18.5 months in the TC arm (stratum-adjusted HR = 0.97 [95% CI = 0.85 to 1.10]; P = .688). Median overall survival was 43.1 months for the TC-Top arm versus 44.5 months for the TC arm (stratum-adjusted HR = 1.01 [95% CI = 0.86 to 1.18]; P = .885). At 3 years, overall survival in both arms was 57% (58.5% in the TC arm and 55.7% in the TC-Top arm). Compared with patients in the TC arm, patients in the TC-Top arm had more grade 3-4 hematologic toxic effects (requiring more supportive care) and more grade 3-4 infections (5.1% versus 2.7%; P = .034) but did not have a statistically significant increase in febrile neutropenia (3.3% versus 3.1%; P = .80). Among patients who had measurable disease (TC, n = 147; TC-Top, n = 145), overall (i.e., complete or partial) response was 69.0% (95% CI = 61.4% to 76.5%) in the TC-Top arm and 76.2% (95% CI = 69.3% to 83.1%) in the TC arm (P = .166). CONCLUSIONS: The sequential addition of topotecan to carboplatin-paclitaxel did not result in superior overall response or progression-free or overall survival. Therefore, this regimen is not recommended as standard of care treatment for ovarian cancer.

In vivo echographic evidence of tumoral vascularization and microenvironment interactions in metastatic orthotopic human neuroblastoma xenografts.

Human neuroblastoma (NB) is the second most frequent solid tumor of childhood and represents a highly heterogeneous disease at clinical and biologic levels. Little progress has been made to improve the poor prognosis of patients with high-stage NB. Tumor progression and metastatic dissemination still represent major obstacles to the successful treatment of advanced stage disease. In order to develop and evaluate new, targeted, therapeutic strategies, fully defined and biologically relevant in vivo models of NB are strongly needed. We have developed an orthotopic model of metastatic human NB in the nude mouse, using 2 well-characterized NB cell lines. Tumor growth, vascular properties and metastatic patterns were investigated using a sensitive and newly developed in vivo echographic technology in addition to immunohistochemistry and PCR analyses. Results show that implantation of low numbers of NB cells directly into the adrenal gland of nude mice resulted in rapid and homogeneous tumor growth without tumor morbidity. Nude mice were shown to rapidly develop highly vascularized adrenal tumors that selectively metastasized to the liver and bone marrow. In addition, the newly formed mouse vessels in orthotopic but not in heterotopic tumors, were found to express the highly angiogenic alphavbeta3 integrin marker, indicating the development of a truly malignant neovasculature in orthotopic conditions only. This observation confirms the impact of the regional microenvironment on tumor biology and suggests the existence of cross-talk with the tumor cells. In conclusion, such model faithfully reproduces the growth, vascular and metastatic patterns as observed in patients. It therefore represents a powerful and biologically relevant tool to improve our understanding of the biology of NB and to develop and assess new antiangiogenic and metastasis-targeted therapies.

Intracellular localization and constitutive endocytosis of CXCR4 in human CD34+ hematopoietic progenitor cells.

CXCR4, the stromal cell-derived factor-1 receptor, plays an important role in the migration of hematopoietic progenitor/stem cells. The surface and cytoplasmic expression of CXCR4 on human hematopoietic CD34(+) cells was investigated. We show that its surface expression is low, whereas a large part of CXCR4 protein is sequestered intracellularly. Using confocal microscopy, we demonstrated that CXCR4 is colocalized with EEA-1, Rab5, Rab4, and Rab11, which are localized in early and recycling endosomes. No significant colocalization of CXCR4 with lysosomal markers CD63 and Lamp-1 was detected. Using antibody feeding experiments, we report a role for CXCR4 constitutive endocytosis in subcellular localization in stably transduced UT7-CXCR4-GFP and CD34(+) cells. Agonist-independent endocytosis of CXCR4 occurs through clathrin-coated vesicles. These data implicate a constitutive endocytosis in the regulation of CXCR4 membrane expression and suggest that constitutive endocytosis may be involved in the regulation of trafficking the human hematopoietic progenitor/stem cells to and in the bone marrow microenvironment.