DOCK4 promotes loss of proliferation in glioblastoma progenitor cells through nuclear beta-catenin accumulation and subsequent miR-302-367 cluster expression.

Glioblastomas (GBM) are lethal primitive brain tumours characterized by a strong intra-tumour heterogeneity. We observed in GBM tissues the coexistence of functionally divergent micro-territories either enriched in more differentiated and non-mitotic cells or in mitotic undifferentiated OLIG2 positive cells while sharing similar genomic abnormalities. Understanding the formation of such functionally divergent micro-territories in glioblastomas (GBM) is essential to comprehend GBM biogenesis, plasticity and to develop therapies. Here we report an unexpected anti-proliferative role of beta-catenin in non-mitotic differentiated GBM cells. By cell type specific stimulation of miR-302, which directly represses cyclin D1 and stemness features, beta-catenin is capable to change its known proliferative function. Nuclear beta-catenin accumulation in non-mitotic cells is due to a feed forward mechanism between DOCK4 and beta-catenin, allowed by increased GSK3-beta activity. DOCK4 over expression suppresses selfrenewal and tumorigenicity of GBM stem-like cells. Accordingly in the frame of GBM median of survival, increased level of DOCK4 predicts improved patient survival.

The impact of sport on health status, psychological well-being and physical performance of adults with haemophilia.

BACKGROUND: There is increasing recognition that sport is important for individuals with haemophilia; however, there remains a paucity of data of the importance of this in adults, many of whom already have joint pathology related to childhood bleeds and treatment access. This multicentre, cross-sectional study presents the impact of sport on health-related quality of life (HRQoL), physical performance and clinical outcomes in adults with haemophilia. RESULTS: Fifty adults aged 35.12±14.7 with mild (n = 12), moderate (n = 10), or severe (n = 28) haemophilia A (70%) or B (30%) from four haemophilia centres across the United Kingdom participated in the study. A total of 64% were overweight/obese according to their BMI; median orthopaedic joint scores using the WFH Orthopaedic Joint Score (OJS) were 6 (range 0-48). On a VAS pain scale (range of 0-10), patients reported mean score of 5.66 ± 2.4. 36% of participants reported not doing any sport, mainly due to their physical condition. However, 64% of participants reported undertaking sporting activity including contact sports, mostly twice per week in average 4 h week(-1) . Participating in sport did not have a statistically significant impact on HRQoL; except in the domain 'sport and leisure' of the Haem-A-QoL. Patients doing more sport reported significantly better HRQoL than those doing less sport (P < 0.005). Those doing sport for more than 4 h week(-1) had a significantly better physical performance than patients doing less sport (assessed with Hep-Test-Q). Encouraging physical activity and sport in older patients with haemophilia may have a direct impact on their HRQoL; thus, education about sport activity should be incorporated into routine haemophilia care.

The miR 302-367 cluster drastically affects self-renewal and infiltration properties of glioma-initiating cells through CXCR4 repression and consequent disruption of the SHH-GLI-NANOG network.

Glioblastoma multiforme (GBM) is the most common form of primary brain tumor in adults, often characterized by poor survival. Glioma-initiating cells (GiCs) are defined by their extensive self-renewal, differentiation, and tumor initiation properties. GiCs are known to be involved in tumor growth and recurrence, and in resistance to conventional treatments. One strategy to efficiently target GiCs in GBM consists in suppressing their stemness and consequently their tumorigenic properties. In this study, we show that the miR-302-367 cluster is strongly induced during serum-mediated stemness suppression. Stable miR-302-367 cluster expression is sufficient to suppress the stemness signature, self-renewal, and cell infiltration within a host brain tissue, through inhibition of the CXCR4 pathway. Furthermore, inhibition of CXCR4 leads to the disruption of the sonic hedgehog (SHH)-GLI-NANOG network, which is involved in self-renewal and expression of the embryonic stem cell-like signature. In conclusion, we demonstrated that the miR-302-367 cluster is able to efficiently trigger a cascade of inhibitory events leading to the disruption of GiCs stem-like and tumorigenic properties.

ATF3 and p15PAF are novel gatekeepers of genomic integrity upon UV stress.

After genotoxic stress, normal cells trigger DNA repair or, if unable to repair, undergo apoptosis to eradicate the cells that bear the risk of becoming tumorigenic. Here we show that repression of the transcription factor, activating transcription factor 3 (ATF3), after ultraviolet (UV)-mediated genotoxic stress impairs the DNA repair process. We provide evidence that ATF3 directly regulates the proliferating cell nuclear antigen (PCNA)-associated factor KIAA0101/p15(PAF). We further show that the expressions of ATF3 and p15(PAF) is sufficient to trigger the DNA repair machinery, and that attenuation of their expression alters DNA repair mechanisms. We show that the expression of p15(PAF) compensates for a lack of ATF3 expression, thereby constituting a major effector of ATF3 in the DNA repair process. In addition, we provide evidence that p15(PAF) expression is required for the correct function of PCNA during DNA repair, as prevention of their interaction significantly alters DNA repair mechanisms. Finally, defective DNA repair, because of the downregulation of p15(PAF) expression, rendered the cells more sensitive to UV-induced cell death. Therefore, our results suggest ATF3 and p15(PAF) as novel gatekeepers of genomic integrity after UV exposure.

[Colon cancer. Study of 153 cases and comparison with a series of 140 historic cases]. / Le cancer du colon. Etude de 153 cas et comparaison avec une serie historique de 140 cas.

The authors study the epidemiological, diagnostic and therapeutic features of 153 consecutive cases of colon cancers collected between 1985 and 1998. They compare the results with those of a previous study performed in the same hospital service (140 cases between 1966 and 1984). It is a series of 79 men and 74 women (sex ratio = 1.07). The mean age was 56.6 +/- 14 years old with 13.7% of the patients who were less than 40 years old. The operability and the resectability were respectively 98.7% and 83.7% with a global operative mortality of 7.9%. According to the Dukes classification, they were 2 A stages, 73 B stages, 32 C stages and 45 D stages. Starting from 1993, 53% of the C stages an 48% of the B stages had an adjuvant chemotherapy. The comparison between our present results and those of our previous series does not show any modification in what regards the mean age, the cancer frequency in young people, the complicated forms proportion and time needed for the diagnosis by comparison to the beginning of symptomatology. The colic cancer prognostic improvement is attained through an earlier diagnosis, making it possible to reduce the developed forms and the complicated forms proportion, the consequence of which is the operative mortality decrease and the log-range survival increase.