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DUSP4 is considered as an oncogenic gene. However, the effect of DUSP4 on the carcinogenesis of clear cell Renal cell carcinoma (CCRCC) is still unclear. In this study, DUSP4 mRNA levels were significantly increased in CCRCC tissues and cell lines. Furthermore, DUSP4 overexpression promotes the proliferation, migration, and tumorigenicity of CCRCC cells while DUSP4 silencing showed the opposite effects. Importantly, both autophagic activity (LC3 conversion rate and LC3 puncta formation) and total death level promoted by DUSP4 silencing were reversed by treatment with 3-MA in CCRCC cells. Moreover, the proliferation and migration of CCRCC cells inhibited by DUSP4 silencing were also recovered by suppression of autophagy with 3-MA. In conclusion, DUSP4 serves as an oncogenic gene in CCRCC carcinogenesis due to its inhibitory effect on autophagic death, indicating the potential value of DUSP4 in the diagnosis and treatment of CCRCC., (© The Author(s) 2021. Published by Oxford University Press on behalf of Japan Society for Bioscience, Biotechnology, and Agrochemistry.)

M-CSF regulates the production, survival, and function of monocytes and macrophages. The MAPKs ERK1/2 are key elements for signal integration downstream of the M-CSFR, and their sustained activation is essential for macrophage differentiation. In this study, we sought to isolate genes whose induction by M-CSF is dependent on persistent MAPK activation, thereby being possibly involved in the commitment of myeloid progenitors to macrophage differentiation. Following SSH between cDNA libraries from FD-Fms cells stimulated by M-CSF for 8 h in the presence or the absence of the MEK inhibitor U0126, we isolated DUSP5. DUSP5 expression is induced by M-CSF in various myeloid cells and acts as a specific negative-feedback regulator of ERK1/2. In FD-Fms cells that proliferate and differentiate toward macrophages in response to M-CSF, overexpression of DUSP5 increased M-CSF-dependent proliferation and strongly decreased differentiation. Similarly, overexpression of DUSP5 in the multipotent EGER-Fms cells not only significantly increased M-CSF-induced proliferation and prevented macrophage differentiation but also favored granulocytic differentiation. Altogether, experiments demonstrated that DUSP5 is implicated in M-CSF signaling and suggested that it may influence myeloid cell fate.

Meiotic maturation in oocytes is a prolonged process that is unique because of cell cycle arrests at prophase of meiosis I (MI) and at metaphase of meiosis II (MII). Fluctuations in cyclin-dependent kinase 1 (CDK1/CDC2A) activity govern meiotic progression, yet little is known about how these fluctuations are achieved. CDC14 is a highly conserved dual-specificity phosphatase that counteracts the function of proteins phosphorylated by CDK. Mammals contain two CDC14 homologs, CDC14A and CDC14B. We report that CDC14B localizes with the meiotic spindle in mouse oocytes, and (unlike somatic cells) it does not localize in the nucleolus. Oocytes that overexpress CDC14B are significantly delayed in resuming meiosis and fail to progress to MII, whereas oocytes depleted of CDC14B spontaneously resume meiosis under conditions that normally inhibit meiotic resumption. Depletion of FZR1 (CDH1), a regulatory subunit of the anaphase-promoting complex/cyclosome that targets cyclin B1 (CCNB1) for ubiquitin-mediated proteolysis, partially restores normal timing of meiotic resumption in oocytes with excess CDC14B. These studies also reveal that experimentally altering CDC14B levels generates eggs with abnormal spindles and with chromosome alignment perturbations. Our data indicate that CDC14B is a negative regulator of meiotic resumption and may regulate MI in mouse oocytes.