Tumor-Derived Microvesicles Induce Proangiogenic Phenotype in Endothelial Cells via Endocytosis

Background: Increasing evidence indicates that tumor endothelial cells (TEC) differ from normal endothelial cells (NEC). Our previous reports also showed that TEC were different from NEC. For example, TEC have chromosomal abnormality and proangiogenic properties such as high motility and proliferative activity. However, the mechanism by which TEC acquire a specific character remains unclear. To investigate this mechanism, we focused on tumor-derived microvesicles (TMV). Recent studies have shown that TMV contain numerous types of bioactive molecules and affect normal stromal cells in the tumor microenvironment. However, most of the functional mechanisms of TMV remain unclear. Methodology/Principal Findings: Here we showed that TMV isolated from tumor cells were taken up by NEC through endocytosis. In addition, we found that TMV promoted random motility and tube formation through the activation of the phosphoinositide 3-kinase/Akt pathway in NEC. Moreover, the effects induced by TMV were inhibited by the endocytosis inhibitor dynasore. Our results indicate that TMV could confer proangiogenic properties to NEC partly via endocytosis. Conclusion: We for the first time showed that endocytosis of TMV contributes to tumor angiogenesis. These findings offer new insights into cancer therapies and the crosstalk between tumor and endothelial cells mediated by TMV in the tumor microenvironment

The Harwel 80/500 keV dual beam facility

SIGLELD:9091.9F(AERE-M--3138) (microfiche). / BLDSC - British Library Document Supply CentreGBUnited Kingdo

COVID-19-related stress, exercise, and oral health-related quality of life among community-dwelling older adults who participated in the CHEER Iwamizawa project, Japan

This study examined the association between coronavirus disease 2019 (COVID-19)-related stress, exercise habits, and oral health-related quality of life (OHRQoL) in a sample of 215 community-dwelling older adults in Japan (57 men, 158 women; M-age = 74.2 years, SD = 6.0). Data were collected during wellness checkups in October 2020 and included participants' demographic characteristics, measures of instrumental activities of daily living and depressive tendencies, number of teeth, oral hypofunction, OHRQoL, COVID-19-related stress, and exercise habits. Four mutually exclusive groups were created, using the presence or absence of COVID-19-related stress and lack of exercise habits as risk factors for poor OHRQoL (no COVID-19-related stress and no lack of exercise, COVID-19-related stress only, lack of exercise habits only, and both COVID-19-related stress and lack of exercise habits). Poisson regression with robust standard errors provided the prevalence ratio for poor OHRQoL. The presence of both COVID-19-related stress and lack of exercise habits (adjusted prevalence ratio: 2.20, 95% CI: 1.31- 3.69) was associated with poor OHRQoL. The results indicate that COVID-19-related stress and exercise habits should be considered when designing oral health and public health initiatives

A multistate stem cell dynamics maintains homeostasis in mouse spermatogenesis.

In mouse testis, a heterogeneous population of undifferentiated spermatogonia (Aundiff) harbors spermatogenic stem cell (SSC) potential. Although GFRα1+ Aundiff maintains the self-renewing pool in homeostasis, the functional basis of heterogeneity and the implications for their dynamics remain unresolved. Here, through quantitative lineage tracing of SSC subpopulations, we show that an ensemble of heterogeneous states of SSCs supports homeostatic, persistent spermatogenesis. Such heterogeneity is maintained robustly through stochastic interconversion of SSCs between a renewal-biased Plvap+/GFRα1+ state and a differentiation-primed Sox3+/GFRα1+ state. In this framework, stem cell commitment occurs not directly but gradually through entry into licensed but uncommitted states. Further, Plvap+/GFRα1+ cells divide slowly, in synchrony with the seminiferous epithelial cycle, while Sox3+/GFRα1+ cells divide much faster. Such differential cell-cycle dynamics reduces mitotic load, and thereby the potential to acquire harmful de novo mutations of the self-renewing pool, while keeping the SSC density high over the testicular open niche.Royal Societ

Karyotypes of HMVECs exposed to hypoxia.

<p>Karyotypes of HMVECs after exposure to normoxia, hypoxia (1% O2), and hypoxia-reoxygenation were analyzed by Q band analysis. A karyotype of one cell in each condition is shown. (A) HMVECs in normoxia were essentially diploid. (B, C) HMVECs exposed to hypoxia and hypoxia-reoxygenation had complex abnormal karyotypes and were aneuploid. (D) The chromosome number of each condition was counted and shown.</p

Assessment of tumor tissue hypoxia and analysis of ploidy in TECs by FISH Hypoxic areas in supermetastatic tumor cryosections were detected using hypoxyprobe.

<p>To analyze the hypoxic area in TECs in in-vivo tumors, frozen sections of tumors were immunostained with anti-CD31 (red) and anti-pimonidazole (green) followed by FISH using a spectrum red-conjugated mouse chromosome-17 locus-specific probe (red spot). Representative CD31-positive ECs in tumor tissue. (A, D, G) The blood vessels in tumor tissue were pimonidazole-positive. (B, E, H) Nuclei are stained with DAPI (blue). Aneuploidy was also observed in ECs of tumor blood vessels exposed to hypoxia. (C, F, I) Pimonidazole-nagative ECs in tumor tissue did not exhibit aneuploidy. (J, K, L) ECs in normal tissue did not exhibit aneuploidy. (M, N, O) Scale bar, 20 μm.</p

Hypoxia induces aneuploidy in HMVECs.

<p>(A, B) After HMVECs were cultured in each condition for 7 days, FISH analysis using a chromosome-7 probe revealed that approximately 22.8% ECs in the hypoxic condition (1% O2) and 19.8% ECs in the hypoxia-reoxygenation condition were aneuploid, whereas 6.4% ECs in the normoxic condition were aneuploid. (C, D) FISH analysis using a chromosome-8 probe revealed that approximately 19.1% ECs in the hypoxic condition and 23.3% of ECs in the hypoxia-reoxygenation condition were aneuploid, whereas 8.5% ECs in the normoxic condition were aneuploid.</p

Association between cell cycle and EC aneuploidy in HMVECs exposed to hypoxia.

<p>(A) Cell number and the cell cycle in HMVECs exposed to hypoxia were analyzed by flow cytometry after staining fixed cells with propidium iodide. In each phase, cultured ECs proliferated for 7 days (normoxia, 2.5-fold; hypoxia (1% O₂), 1.6-fold; hypoxia-reoxygenation, 2.4-fold versus Day 0 cell numbers). (B) We analyzed the distribution of ECs throughout the cell cycle by flow cytometry. There was no significant difference in cell-cycle distribution between conditions of normoxia and hypoxia. The experiment was repeated three times, and representative data is shown.</p