Study of Chemical Compositions and Anticancer Effects of Paris polyphylla var. Chinensis Leaves.

Paris polyphylla var. chinensis (Franch.) Hara is a perennial herb belonging to the Trilliaceae family. Ultraperformance liquid chromatography quadrupole time-of-flight mass spectrometry (UPLC/Q-TOF MS) was used to detect the composition of different fractions of Paris polyphylla var. chinensis leaves. Meanwhile, the extracts of different fractions were evaluated for their cytotoxic activities against four selected human cancer cell lines and one human normal epithelial cell line based on the MTT assay method. Multivariate statistical analysis was performed to screen differential compounds and to analyze the distributions between different fractions. Finally, more than 60 compounds were obtained and identified from the different fractions of Paris polyphylla var. chinensis leaves, and the chloroform and n-butanol extracts showed significant cytotoxic effects on these four cancer cells. Several compounds were preliminarily identified from different fractions, including 36 steroidal saponins, 11 flavonoids, 10 ceramides, 8 lipids, 6 organic acids, and 8 other compounds. Various compounds were screened out as different chemical components of different fractions, which were considered as a potential substance basis for the cytotoxicity of Paris polyphylla var. chinensis leaves.

The association of 6 variants of 8q24 and the risk of glioma: A meta-analysis.

With the advances in sequencing technologies and genome-wide association studies (GWAS), several inherited variants that increase glioma risk have been identified. Ten studies including 8818 cases and 17,551 controls were collected to conduct a meta-analysis to evaluate the associations between 6 variants in 8q24 and glioma risk. Of the 6 variants located in 8q24, 2 have strong significant associations with the risk of glioma, including rs4295627 (P = .003, odds ratio [OR] = 1.21), rs55705857 (P = 2.31 × 10, OR = 3.54). In particular, both homozygous GG (P = 1.91 × 10, OR1 = 2.01) and heterozygous GT (P = 7.75 × 10, OR2 = 1.35) genotypes of rs4295627 were associated with glioma risk. Further studies are needed to explore the role of the 8q24 variants involved in the etiology of glioma.

[The distribution of ATPase during the pollen development of Allium cepa L].

The distribution of ATPase in pollen of Allium cepa L. was studied using Pb3 precipitation technique during pollen development. Only some ATPase precipitates were located in the nucleus of microspore mother cells (MMC) and a few in its cytoplasm. After meiosis of MMC,many ATPase precipitates appeared in the exine of pollen wall of microspore even it was in tetrad, suggesting that ATPase from tapetum is necessary during pollen wall construction. The intine of pollen wall of microspore was synthesized at its late stage and consisted of cellular material which was from microspore. There were also many ATPase precipitates in intine,and the ATPase came from microspore. Then ATPase precipitates in vegetative cell increased and that in generative cell decreased during the development of 2-cellular pollen,suggesting the differentiation of vigor between both cells. The physiological functions of ATPase in developing pollen of Allium cepa L. were analyzed.

Effects of RNAi-mediated Smad4 silencing on growth and apoptosis of human rhabdomyosarcoma cells.

Transforming growth factor-beta (TGF-beta) signals through membrane-bound heteromeric serine/threonine kinase receptors. Upon ligand binding, TGF-beta activates intracellular Smad proteins and regulates proliferation and apoptosis in various cell types. To demonstrate the effects of TGF-beta/Smad signal on growth and apoptosis of human embryonal rhabdomyosarcoma (RMS) cells, a strategy of RNAi-mediated 'gene silencing' of Smad4 was used to interrupt endogenous TGF-beta/Smad signaling in an RMS cell line, RD, and the regulation of exogenous TGF-beta1 to growth and apoptosis of the cells was also determined. Physiologically, TGF-beta/Smad signaling was essential for the normal growth of RD. The interruption of endogenous TGF-beta/Smad signaling by RNAi significantly suppressed the growth of RD cells and dramatically induced apoptosis of RD cells. Exogenous TGF-beta1 also inhibited the growth of RD cells, but had no effect on apoptosis. It also partially counteracted the growth inhibition and apoptosis induced by Smad4 silencing in RD cells. These findings provide a new insight into how TGF-beta/Smad signaling regulates the growth and apoptosis of cancer cells. Moreover, as a powerful tool, shRNA interference suppresses endogenous Smad4 gene expression and subsequently modulates cell growth and apoptosis, which may provide a novel basis for the development of rational intervention strategies in RMS therapy.

[ATPase distribution in fertile and sterile anther of a genic male sterile Chinese cabbage].

Lead precipitation technique was used to locate Adenosine Triphosphatase (ATPase) in the fertile and sterile anthers of a genic male sterile Chinese cabbage (Brassica campestris L. ssp. Chinensis Makino var. communis Tsen et Lee),which would help us to understand the relationship between ATPase and sterility of anthers of the cabbage. At megaspore mother cell (MMC) of fertile anther many ATPase reactive precipitates were located in nucleus but few of the precipitates in cytoplasm of the cell. Meantime, some ATPase reactive precipitates also specially appeared in mitochondria of the MMC. After meiosis of MMC, the precipitates in cytoplasm of early microspores increased evidently and then decreased step by step with development. The ATPase reactive precipitates in tapetal cell also increased ultimately in early microspore stage and then decreased with development of anther. When microspore formed a large vacuole, which is late stage of microspore, the ATPase reactive precipitates were located in its mitochondria. After microspores mitosis a few of the ATPase reactive precipitates appeared in pollen grains and tapetal cells. More ATPase reactive precipitates appear in MMC of sterile anther than in fertile anther but fewer of them in mitochondria. Although more ATPase granules appear in abnormal tetrad microspores which degenerate by cytoplasm shrinkage and plasmolysis. The relation between ATPase and male sterility of the cabbage was discussed.

Systematic analysis of the TGF-beta/Smad signalling pathway in the rhabdomyosarcoma cell line RD.

Transforming growth factor-beta (TGF-beta) is a multifunctional regulator of cell growth and differentiation, whose actions are highly cell type specific. To study the role of the TGF-beta1 autocrine loop in regulating growth and myogenic differentiation in the human rhabdomyosarcoma cell line, RD, an attempt was made to establish a framework for the expression of several components of TGF-beta1/Smad signalling pathway at the mRNA and protein levels by reverse transcription-polymerase chain reaction (RT-PCR) and Western blot analysis in RD cells compared with the normal myoblasts. Higher exogenous concentration of TGF-beta1 was necessary to reach a growth-inhibition effect, whereas TGF-beta1 downregulated the expression of myosin heavy-chain mRNA at lower concentrations than that was required for growth inhibition. Treatment with TGF-beta1 significantly decreased the number of sarcomeric actin and myosin-expressing cells. In this study, we have shown that RD cells displayed higher expression of TbetaRI, TbetaRII, Smad2 and Smad4 at both the mRNA and protein levels than myoblasts. Smad3 and Smad7 mRNA were expressed at higher level in RD cells than in myoblasts. The staining patterns of TbetaR and Smads suggest that they may transduce different TGF-beta1 signalling in RD cells than in myoblasts. TGF-beta1 signalling induced a rapid relocation of Smad2 to the nucleus; in contrast, Smad4 remained localized to the cytoplasm unless it was coexpressed with Smad2. These studies suggest that signalling from the cell surface to the nucleus through Smad proteins is a required component of TGF-beta1-induced cell response in RD cells. The RD cell line is a suitable model to study the TGF-beta autocrine loop involved in growth and differentiation of RMS.