Growth Regulation in Vitro and the Role of Serum

Author(s):  
R. F. Brooks
Keyword(s):  
Author(s):  
J. T. Gau ◽  
M. L. Grove ◽  
S. Strom ◽  
R. Orsini ◽  
K. C. Song ◽  
...  

Prostate cancer is the most common tumor in men in the U.S.A. The regulation of growth control in normal prostate cells and its contribution to tumor progression is a subject of intense investigation.Recently our group developed culture techniques that allowed us to study normal and neoplastic human prostate epithelial cells from human prostatectomy specimens. Since quantitative evaluation of intracellular compartments will be critical to defining the role of membrane trafficking in the growth regulation, we used TEM and QIAM to characterize normal and neoplastic prostate epithelial cells invivo, as well as in vitro. This work will serve as a baseline to subsequent studies using perturbants of cell trafficking and conditions ;hat promote or block cellular growth, to investigate the role of growth factors and stromal/epithelial nteraction in prostate growth regulation.Normal and neoplastic tissues were sampled for ultrastructural examination from grid mapped radical prostatectomy specimens that were processed for whole mounts. The SV40 immortalized "normal" prostate cell line (P69) was provided by Dr. Strom.


2003 ◽  
Vol 15 (1) ◽  
pp. 37 ◽  
Author(s):  
M. Pantaleon ◽  
H. Jericho ◽  
G. Rabnott ◽  
P. L. Kaye

Insulin-like growth factor II (IGF-II) and its receptor, the IGF-II/mannose-6-phosphate (IGF-II/M6P) receptor, are first expressed from the zygotic genome at the two-cell stage of mouse development. However, their role is not clearly defined. Insulin-like growth factor II is believed to mediate growth through the heterologous type 1 IGF and insulin receptors, whereas the IGF-II/M6P receptor is believed to act as a negative regulator of somatic growth by limiting the availability of excess levels of IGF-II. These studies demonstrate that IGF-II does have a role in growth regulation in the early embryo through the IGF-II/M6P receptor. Insulin-like growth factor II stimulated cleavage rate in two-cell embryos in vitro. Moreover, this receptor is required for the glycaemic response of two-cell embryos to IGF-II and for normal progression of early embryos to the blastocyst stage. Improved development of embryos in crowded culture supports the concept of an endogenous embryonic paracrine activity that enhances cell proliferation. These responses indicate that the IGF-II/M6P receptor is functional and likely to participate in such a regulatory circuit. The functional role of IGF-II and its receptor is discussed with reference to regulation of early development.


2021 ◽  
Vol 6 (1) ◽  
Author(s):  
Zhiyi Cheng ◽  
Guiyuan Liu ◽  
Chuanjiang Huang ◽  
Xiaojun Zhao

AbstractCancer cell autophagy has been associated with the progression of gastric cancer (GC), but involvement of long noncoding RNAs (lncRNAs) remains unclear. Initial bioinformatics analysis has identified abnormally highly expressed KLF5 in GC, as well as the predicted regulatory mechanism associating with lncRNA DANCR, miR-194, and AKT2. The expression of KLF5, DANCR, and AKT2 in GC tissue was upregulated, and the expression of miR-194 was downregulated. We knocked KLF5 down and manipulated the expression of DANCR, miR-194, and AKT2 to characterize their roles in GC cell viability, autophagy, and apoptosis. The mechanistic investigations revealed that KLF5 activated the transcription of DANCR in the promoter region and elevated its expression. DANCR acted as a miR-194 sponge to repress its expression in GC. MiR-194 targeted and inhibited AKT2 expression. Silencing KLF5 augmented GC cell autophagy, apoptosis and impeded its viability through the DANCR/miR-194/AKT2 axis. The tumor-inhibiting properties of KLF5 knockdown were substantiated in vivo. Together, our study uncovered the oncogenic role of KLF5-dependent lncRNA DANCR transcription in GC in vivo and in vitro, which implicates the miR-194/AKT2 axis in tumor growth regulation, and it may be a potential therapeutic target for human GC.


Author(s):  
Janet H. Woodward ◽  
D. E. Akin

Silicon (Si) is distributed throughout plant tissues, but its role in forages has not been clarified. Although Si has been suggested as an antiquality factor which limits the digestibility of structural carbohydrates, other research indicates that its presence in plants does not affect digestibility. We employed x-ray microanalysis to evaluate Si as an antiquality factor at specific sites of two cultivars of bermuda grass (Cynodon dactvlon (L.) Pers.). “Coastal” and “Tifton-78” were chosen for this study because previous work in our lab has shown that, although these two grasses are similar ultrastructurally, they differ in in vitro dry matter digestibility and in percent composition of Si.Two millimeter leaf sections of Tifton-7 8 (Tift-7 8) and Coastal (CBG) were incubated for 72 hr in 2.5% (w/v) cellulase in 0.05 M sodium acetate buffer, pH 5.0. For controls, sections were incubated in the sodium acetate buffer or were not treated.


Author(s):  
David B. Warheit ◽  
Lena Achinko ◽  
Mark A. Hartsky

There is a great need for the development of a rapid and reliable bioassay to evaluate the pulmonary toxicity of inhaled particles. A number of methods have been proposed, including lung clearance studies, bronchoalveolar lavage analysis, and in vitro cytotoxicity tests. These methods are often limited in scope inasmuch as they measure only one dimension of the pulmonary response to inhaled, instilled or incubated dusts. Accordingly, a comprehensive approach to lung toxicity studies has been developed.To validate the method, rats were exposed for 6 hours or 3 days to various concentrations of either aerosolized alpha quartz silica (Si) or carbonyl iron (CI) particles. Cells and fluids from groups of sham and dust-exposed animals were recovered by bronchoalveolar lavage (BAL). Alkaline phosphatase, LDH and protein values were measured in BAL fluids at several time points postexposure. Cells were counted and evaluated for viability, as well as differential and cytochemical analysis. In addition, pulmonary macrophages (PM) were cultured and studied for morphology, chemotaxis, and phagocytosis by scanning electron microscopy.


2012 ◽  
Vol 82 (3) ◽  
pp. 228-232 ◽  
Author(s):  
Mauro Serafini ◽  
Giuseppa Morabito

Dietary polyphenols have been shown to scavenge free radicals, modulating cellular redox transcription factors in different in vitro and ex vivo models. Dietary intervention studies have shown that consumption of plant foods modulates plasma Non-Enzymatic Antioxidant Capacity (NEAC), a biomarker of the endogenous antioxidant network, in human subjects. However, the identification of the molecules responsible for this effect are yet to be obtained and evidences of an antioxidant in vivo action of polyphenols are conflicting. There is a clear discrepancy between polyphenols (PP) concentration in body fluids and the extent of increase of plasma NEAC. The low degree of absorption and the extensive metabolism of PP within the body have raised questions about their contribution to the endogenous antioxidant network. This work will discuss the role of polyphenols from galenic preparation, food extracts, and selected dietary sources as modulators of plasma NEAC in humans.


Planta Medica ◽  
2012 ◽  
Vol 78 (11) ◽  
Author(s):  
HM Lee ◽  
TG Ahn ◽  
CW Kim ◽  
HJ An
Keyword(s):  

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