Spontaneous spheroids from alveolar bone-derived mesenchymal stromal cells maintain pluripotency of stem cells by regulating hypoxia-inducible factors

BACKGROUND: Spontaneous spheroid culture is a novel three-dimensional (3D) culture strategy for the rapid and efficient selection of progenitor cells. The objectives of this study are to investigate the pluripotency and differentiation capability of spontaneous spheroids from alveolar bone-derived mesenchymal stromal cells (AB-MSCs); compare the advantages of spontaneous spheroids to those of mechanical spheroids; and explore the mechanisms of stemness enhancement during spheroid formation from two-dimensional (2D) cultured cells. METHODS: AB-MSCs were isolated from the alveolar bones of C57BL/6 J mice. Spontaneous spheroids formed in low-adherence specific culture plates. The stemness, proliferation, and multi-differentiation capacities of spheroids and monolayer cultures were investigated by reverse transcription quantitative polymerase chain reaction (RT-qPCR), immunofluorescence, alkaline phosphatase (ALP) activity, and oil-red O staining. The pluripotency difference between the spontaneous and mechanical spheroids was analyzed using RT-qPCR. Hypoxia-inducible factor (HIFs) inhibition experiments were performed to explore the mechanisms of stemness maintenance in AB-MSC spheroids. RESULTS: AB-MSCs successfully formed spontaneous spheroids after 24 h. AB-MSC spheroids were positive for MSC markers and pluripotency markers (Oct4, KLF4, Sox2, and cMyc). Spheroids showed higher Ki67 expression and lower Caspase3 expression at 24 h. Under the corresponding conditions, the spheroids were successfully differentiated into osteogenic and adipogenic lineages. AB-MSC spheroids can induce neural-like cells after neurogenic differentiation. Higher expression of osteogenic markers, adipogenic markers, and neurogenic markers (NF-M, NeuN, and GFAP) was found in spheroids than in the monolayer. Spontaneous spheroids exhibited higher stemness than mechanical spheroids did. HIF-1α and HIF-2α were remarkably upregulated in spheroids. After HIF-1/2α-specific inhibition, spheroid formation was significantly reduced. Moreover, the expression of the pluripotency genes was suppressed. CONCLUSIONS: Spontaneous spheroids from AB-MSCs enhance stemness and pluripotency. HIF-1/2α plays an important role in the stemness regulation of spheroids. AB-MSC spheroids exhibit excellent multi-differentiation capability, which may be a potent therapy for craniomaxillofacial tissue regeneration.

Research progress of pyruvate kinase type M2 in hepatocellular carcinoma / 中华肝脏病杂志

Primary hepatocellular carcinoma is one of the most common high-grade malignant tumors in the world. Its incidence ranks fifth among malignant tumors in China, and various therapeutic measures have poor curative effect. Pyruvate kinase type M2 is a key enzyme in the glycolytic pathway, and its abnormal expression in liver cancer is closely related to the proliferation, metastasis, diagnosis, treatment, prognosis, as well as drug and radiation resistance. Therefore, multi-pathway targeted regulation of pyruvate kinase type M2 use is expected to become a new direction for the treatment of primary liver cancer.

Effect of short hairpin RNA lentivirus-mediated silencing of pleomorphic adenoma gene like-2 on proliferation, migration and invasion of hepatocellular carcinoma cells / 解剖学报

Objective To investigate the effect of short hairpin RNA(shRNA)-mediated pleomorphic adenoma gene like-2 (PALAG2) silencing on the malignant behavior of hepatocellular carcinoma cells and its mechanism. Methods Real-time PCR and Western blotting were used to detect the expression level of PLAGL2 in liver cancer tissues and adjacent tissues. Hepatoma cells MHCC97-L were cultured in vitro, the lentiviral vector plasmid PLAGL2-shRNA and control NC-shRNA were constructed, transfected into MHCC97-L cells, and stable transfected strains were selected with puromycin. CCK-8 and Transwell chamber assay detected the proliferation activity and the number of migration and invasion of MHCC97-L cells after silencing PLAGL2. Western blotting was used to detect the expression of p-PI3K and p-Akt proteins. The PI3K/ Akt signaling pathway activator was used to treat MHCC97-L cells to detect cell proliferation, migration and invasion. Results The expression of PLAGL2 was significantly increased in liver cancer tissue (P < 0. 05). Transfection of 9 strains of MHCC97-L cells with PLAGL2-shRNA could significantly reduce the expression level of PLAGL2, and the ability of proliferation, migration, and invasion of MHCC97-L cells was also weakened (P<0. 05), and the expression levels of p-PI3K, and p-Akt were inhibited (P<0. 05), PI3K/ Akt activator could obviously reverse the above phenomenon. Conclusion shRNA lentiviral vector pathway can effectively silence the expression of PLAGL2 gene in hepatocarcinoma cells. Silencing of PLAGL2 can significantly inhibit the malignant behavior of proliferation, migration and invasion of hepatocarcinoma cells, and its mechanism may be related to the inhibition of PI3K / Akt signaling pathway activation.

Phylogenetic analysis of Echinococcus granulosus genotypes based on the GenBank database / 中国血吸虫病防治杂志

Objective To analyze the sequences of the cytochrome C oxidase subunit I (Cox1) gene of various Echinococcus granulosus genotypes that are currently recorded in the GenBank database, so as to investigate the genetic variation and differentiation of the E. granulosus genotypes across the world. Methods The sequences of the Cox1 gene of various E. granulosus genotypes that are currently recorded in the GenBank database were collected, and the same sequences of the Cox1 gene identified from a region were excluded. The mutation sites among the Cox1 gene sequences were identified and a phylogenetic tree was created based on the Cox1 gene. Results Transversion mutation was the predominant type of mutation in the Cox1 gene of E. granulosus. The same Cox1 gene sequence was found in E. granulosus G1, G6 and G7 genotypes isolated from various geographical locations across the world, with the corresponding GenBank accession numbers of KY766891, MH300971 and MH301007, respectively. Phylogenetic analysis revealed that E. granulosus G10 genotype had a remarkable geographical aggregation. Conclusions E. granulosus G1, G6 and G7 genotypes have primitive Cox1 gene sequences. There is a geographical aggregation of the E. granulosus G10 genotype in the phylogenetic tree, which has a tendency towards reproductive isolation.

Present situation and progress of comprehensive treatments for hepatic alveolar echinococcosis / 中国血吸虫病防治杂志

Alveolar echinococcosis is a parasitic zoonosis that severely damages human health. Currently, radical surgical resection is the first choice for hepatic alveolar echinococcosis. For the advanced hepatic echinococcosis patients with refractory radical resection, the palliative surgery combined with chemotherapy, liver transplantation, drug therapy, and radiofrequency microwave ablation may provide comprehensive tools. This article reviews the current situation and progress of comprehensive treatments for hepatic alveolar echinococcosis.

Present situation and progress of comprehensive treatments for hepatic alveolar echinococcosis / 中国血吸虫病防治杂志

Alveolar echinococcosis is a parasitic zoonosis that severely damages human health. Currently, radical surgical resection is the first choice for hepatic alveolar echinococcosis. For the advanced hepatic echinococcosis patients with refractory radical resection, the palliative surgery combined with chemotherapy, liver transplantation, drug therapy, and radiofrequency microwave ablation may provide comprehensive tools. This article reviews the current situation and progress of comprehensive treatments for hepatic alveolar echinococcosis.

Clinical efficacy and mechanism of total glucosides from white paeony for radioactive liver damage / 中国中药杂志

To discuss the effects of total glucosides from white paeony on preventing and treating radioactive liver damage, and explore its possible mechanisms. Thirty-six patients with primary hepatic carcinoma from 105th Hospital of Chinese PLA were treated with 3-dimensional conformal radiotherapy and randomly divided into simple irradiation group, total glucosides from white paeony group, and control group. The levels of AST, ALT, HA, LN, PCⅢ, CIV and TGF-β1 in serum of various groups were determined by using ELISA method. As compared with the simple irradiation group and control group, total glucosides from white paeony could obviously decrease the levels of AST, ALT, HA, LN, PCⅢ, CIV and TGF-β1(P<0.05, P<0.01). The results showed that the total glucosides from white paeony could effectively prevent and treat radioactive liver damage, and its mechanism might be associated with decreasing the levels of TGF-β1, and inhibiting the synthesis of collagen synthesis.

Current development of the second generation of mTOR inhibitors as anticancer agents / 癌症

The mammalian target of rapamycin (mTOR), a serine/threonine protein kinase, acts as a "master switch" for cellular anabolic and catabolic processes, regulating the rate of cell growth and proliferation. Dysregulation of the mTOR signaling pathway occurs frequently in a variety of human tumors, and thus, mTOR has emerged as an important target for the design of anticancer agents. mTOR is found in two distinct multiprotein complexes within cells, mTORC1 and mTORC2. These two complexes consist of unique mTOR-interacting proteins and are regulated by different mechanisms. Enormous advances have been made in the development of drugs known as mTOR inhibitors. Rapamycin, the first defined inhibitor of mTOR, showed effectiveness as an anticancer agent in various preclinical models. Rapamycin analogues (rapalogs) with better pharmacologic properties have been developed. However, the clinical success of rapalogs has been limited to a few types of cancer. The discovery that mTORC2 directly phosphorylates Akt, an important survival kinase, adds new insight into the role of mTORC2 in cancer. This novel finding prompted efforts to develop the second generation of mTOR inhibitors that are able to target both mTORC1 and mTORC2. Here, we review the recent advances in the mTOR field and focus specifically on the current development of the second generation of mTOR inhibitors as anticancer agents.

Application of biomarkers in research of breast cancer / 上海第二医科大学学报

Breast cancer is by far the most common cancer for females.The recent researches focus on early diagnosis,optimal adjuvant therapy and curative effect surveillance.The paper summarizes the application of tissue and fluid tumor markers in the diagnosis,treatment,curative effect surveillance and prognostic prediction of breast cancer,which include widely-accepted estrogen receptors,HER2-neu and CA15-3,and novel ones such as Cyclin E,TIMP-1,RAR-?,hK10 and BRCA-1.