Melatonin is an important immune modulator with antitumor functions, and increased CD4 þ CD25 þ regulatory T cells (Tregs) have been observed in tumor tissues of patients and animal models with gastric cancer. However, the relationship between melatonin and Tregs remains unclear. To explore this potential connection, we performed an in vivo study by inoculating the murine foregastric carcinoma (MFC) cell line in mice and then treated them with different doses of melatonin (0, 25, 50, and 100 mg/kg, i.p.) for 1 week. The results showed that melatonin could reduce the tumor tissue and decrease Tregs numbers and Forkhead box p3 (Foxp3) expression in the tumor tissue. An in vitro study was also performed to test the effects of purified Tregs on melatonin-mediated inhibition of MFC cells. The cell cultures were divided into three groups: 1) MFCþ Tregs; 2) MFC only; and 3) MFCþCD4 þ CD25 À T cells. After treatment with different concentrations of melatonin (0, 2, 4, 6, 8, and 10 mM) for 24 h, a dose-dependent apoptosis and cell cycle arrest at the G2/M phase was detected in melatonin-treated MFC at melatonin concentration higher than 4 mM. There were no significant differences in the rates of apoptosis and cell cycle distributions of MFC among the three groups. In conclusion, the antigastric cancer effect of melatonin is associated with downregulation of CD4 þ CD25 þ Tregs and its Foxp3 expression in the tumor tissue. Anat Rec, 294:781-788, 2011. V V C 2011 Wiley-Liss, Inc.

No abstract

No abstract

Peroxiredoxin (Prx) II belongs to a recently discovered family of peroxidases that play important roles in antioxidation and signal transduction. In this study, we aimed to study the localization and expression of Prx II in the mouse ovary, oviduct, and uterus, and preimplantation embryos. Immunohistochemical staining analysis showed that, in the ovary, Prx II was expressed in the oocyte cytoplasm of the primary follicle, the secondary follicle, and the premature follicle; Prx II was expressed in germinal vesicle-intact oocytes (GV oocytes) and metaphase II eggs (MII eggs), as well as at various stages in early embryos. Reverse transcription polymerase chain reaction (RT-PCR) results indicated that the Prx II mRNA was expressed at a high level in GV eggs, slightly lower levels in MII eggs, and had no detectable expression in four-cell embryos and early blastocysts. In the oviduct, Prx II was expressed in the epithelia, while in the uterus Prx II was mainly distributed in the endometrial stroma. Taken together, our results suggest that Prx II plays a key antioxidation role in the maturation of oocytes and development of early embryos, thus providing crucial experimental evidence for further exploring the function of Prx II in the development of oocytes and preimplantation embryos. Anat Rec,[293][294][295][296][297]

Zygotic genome activation (ZGA) is one of the most critical events at the beginning of mammalian preimplantation embryo development (PED). The mechanisms underlying mouse ZGA remain unclear although it has been widely studied. In the present study, we identified that tricho-rhinophalangeal syndrome 1 (TRPS1), an atypical GATA family member, is an important factor for ZGA in mouse PED. We found that the Trps1 mRNA level peaked at the one-cell stage while TRPS1 protein did so at the two/four-cell stage. Knockdown of Trps1 by the microinjection of Trps1 siRNA reduced the developmental rate of mouse preimplantation embryos by approximately 30%, and increased the expression of ZGA marker genes MuERV-L and Zscan4d via suppressing the expression of major histone markers H3K4me3 and H3K27me3. Furthermore, Trps1 knockdown decreased the expression of Sox2 but increased Oct4 expression. We conclude that TRPS1 may be indispensable for zygotic genome activation during mouse PED.

During in vitro cultivation of preimplantation embryos, the balance between ROS production and clearance is disturbed and may lead to incompetent embryos, which might be a main reason of IVF-ET failure. Icariin (ICA) is reported to be active in clearing ROS. The present study aimed to investigate whether ICA could reverse H2O2 pretreatment-induced mouse preimplantation embryo development arrest and, furthermore, to study the underlying mechanisms by detecting ROS levels, mitochondrial membrane potential (ΔΨm), and zygotic gene expression. The results showed that, after pretreating mouse 1-cell embryos with 40 μM or 60 μM H2O2 for 30 min, the developmental rate of each stage embryos decreased obviously. And by adding 40 μM ICA, the developmental arrest of 60 μM H2O2 pretreated preimplantation embryos was significantly reversed. Immunostaining results showed that, comparing with the control group, ROS levels of H2O2 pretreated 1-cell embryos were elevated and ΔΨm levels decreased. By adding ICA, the ROS levels of H2O2 pretreated 1-cell embryos were decreased and ΔΨm levels were elevated. Furthermore, RT-qPCR results showed that the addition of ICA reversed the H2O2-induced downregulation of eIF-1A mRNA expression levels. These results indicate that ICA, when used in appropriate concentration, could decrease ROS levels, increase ΔΨm levels, and modulate the expression of zygotic gene activation (ZGA) marker gene eIF-1A, and thus promote the development of H2O2-pretreated mouse preimplantation embryos.

Phosphorylated Ser473-Akt (p-Ser473-Akt) is extensively studied as a correlate for the activity of Akt, which plays an important role in mouse oogenesis and preimplantation embryogenesis. However, little progress has been made about its effect on the mouse zygotic genome activation (ZGA) of 2-cell stage in mouse preimplantation embryos. In this study, we confirmed its localization in the pronuclei of 1-cell embryos and found that p-Ser473-Akt acquired prominent nucleus localization in 2-cell embryos physiologically. Akt specific inhibitors API-2 and MK2206 could inhibit the development of mouse preimplantation embryos in vitro, and induce 2-cell arrest at certain concentrations. 2-cell embryos exposed to 2.0 lmol/L API-2 or 30 lmol/L MK2206 displayed attenuated immunofluorescence intensity of p-Ser473-Akt in the nucleus. Simultaneously, qRT-PCR results revealed that 2.0 lmol/L API-2 treatment significantly downregulated the mRNA pattern of MuERV-L and eIF-1A, two marker genes of ZGA, suggesting a defect in ZGA compared with that of control group. Collectively, our work demonstrated the nuclear localization of p-Ser473-Akt during major ZGA, and Akt specific inhibitors API-2 and MK2206 which led to 2-cell arrest inhibited p-Ser473-Akt from translocating into the nucleus of 2-cell embryos with defective ZGA as well, implying p-Ser473-Akt may be a potential player in the major ZGA of 2-cell mouse embryos.

Objective To explore the clinical and pathologic features of ovarian juvenile granulosa cell tumors (JGCTs). Methods Clinical data, histopathologic observations, immunohistochemical results, FOXL2 mutation status, and follow-up information of 7 JGCT cases were studied. Results The patients most commonly presented with abdominal distension and pain (5 cases), followed by precocious puberty (1 case) and a pelvic mass (1 case). Six patients had stage I disease, and 1 had stage IV disease. The microscopic examinations typically showed lobular growth punctuated by variably sized and shaped follicles. Rare features included a reticular-cystic appearance mimicking a yolk sac tumor (2 cases), a lobular appearance similar to a sclerosing stromal tumor (1 case), strands and cords (1 case), pseudopapillary appearance (2 cases), spindle cell appearance (1 case), microcystic appearance (1 case), hobnail cells (1 case), and rhabdomyoid cells (1 case). No FOXL2 mutation was encountered. After a median follow-up of 53 months, only 1 patient with a strongly diffuse TP53-positive tumor died of the disease, and 2 successfully had babies. Conclusions JGCT is a rare neoplasm with a wide morphologic spectrum and is easily confused with other tumors. Familiarity with the characteristics, rare atypical appearances, and immunohistochemical results may aid in obtaining a correct diagnosis.