细胞技术

Gene targeting is the modification of specific DNA sequences in a living organism. Three requirements must be met in order for gene targeting to be successful (1). The process must be directed, so that it affects only the locus of choice. The targeting procedure requires specificity, such that a pred ...

The ability of a tumor suppressor gene to inhibit cell growth is critical for its tumor suppression. Such activity is carried out largely by inducing cell cycle arrest and apoptosis. For example, when the p53 tumor suppressor gene is activated by DNA damage (1), it inhibits the growth of tumor cells by in ...

Determination of cell cycle distribution is an important tool in cell biology. Flow cytometric analysis of cellular DNA can provide rapid quantitative information about DNA ploidy and cell cycle distribution. Presented here are three basic protocols for analysis of DNA by flow cytomet ...

The number of kinases, enzymes whose purpose is to phosphorylate other proteins on serine, threonine, or tyrosine residues, in mammalian cells is presently known to number in the several hundreds or even thousands (1,2). This particular posttranslational modification can dramatica ...

In a noncancerous mammalian cell, the growth-promoting effects of proto-oncogenes are counterbalanced by the growth-constraining effects of tumor suppressor genes (TSGs). The net result is a masterfully orchestrated display of cell proliferation in the absence of tumorigenes ...

About 80% of all human cancers are carcinomas, representing oncogenic transformation of epithelial cells. In-vitro models of epithelial cell transformation are therefore of great interest to elucidate the molecular mechanisms of human cancer. Malignant transformation is a mul ...

The underlying premise of structural biology is that the fundamental understanding of biological functions lies in the three-dimensional structures of proteins and other biopolymers. The two well-established experimental methods for determining the high-resolution str ...

In the early 1970s, Judah Folkman first proposed the hypothesis that tumor growth was dependent on the recruitment of blood vessels, a process called angiogenesis, and that angiogenesis was both an important stage in tumor development and a promising therapeutic target. Based on his observ ...

The transition from normal to cancerous tissue frequently takes years to occur. Epithelial tumors in particular can exist as premalignant lesions for prolonged periods of time, and even then only a low proportion of benign tumors undergo malignant transformation (1,2). Once tumors have f ...

The utilization of mice as a model for human cancer goes back to the generation of inbred laboratory strains in the early twentieth century. Some inbred mouse strains were genetically predisposed to certain types of cancer, providing an early indication that genetic manipulation of a species ...

As interest in cell death has recently increased, many new techniques have been developed to detect and quantitate apoptosis in cells. Multiparameter flow cytometric-based assays provide statistical information on measured parameters at the single-cell level, and are therefore ...

With 1600 eyes, a pair of antennae, 6 legs, and an open circulatory system, the fruit fly Drosophila melanogaster may seem an unlikely model for the host of pathologies resulting from human cancers. However, the results of a century of research in Drosophila only accents the fundamental similarit ...

Tumor progression can very broadly be def ined as the progression from a less advanced to a more advanced neoplasm, due to the acquisition of genetic or other cell biologic alterations (Fig. 1). Implicit in this definition is the hypothesis that these acquired cellular alterations endow neopla ...

The functions of many proteins are likely to be regulated by phosphorylation. Thus, antibodies that can recognize specifically phosphorylated sites on proteins have a wide variety of uses for studying the function and regulation of phosphoproteins. We have improved methods for gener ...

Detection of mutations is of central importance in the study of genetic and malignant diseases. Mutation detection helps us in understanding the protein structure, function, and expression. More than that, it is also important for presymptomatic/antenatal diagnosis, confirmati ...

The ubiquitin-dependent proteolysis pathway constitutes a major pathway in the cell for selective protein degradation. The covalent attachment of multiple ubiquitin molecules to lysine residues of a target protein serves to signal its recognition and rapid degradation by the 26S p ...

Studies of human cancer predisposition syndromes and mouse knockout models have revealed several connections between defects in DNA damage response and tumorigenesis. Several recently identified genes, including ATM (ataxia telangiectasia mutated), BRCA1, BRCA2, and Nbs1 ( ...

With recent advances in the Human Genome Project and progress in microarray and gene chip technology, an explosion of genomic information is becoming available. One of the major ways to understand this vast amount of data is by bestowing topological information to help us identify the functio ...

Several approaches, generally referred to as rapid amplification of cDNA ends, are currently used as a means of obtaining full-length cDNA clones by PCR. However, these protocols are not infallible and in specific instances they have proven unsuccessful, emphasizing a need for further ref ...

Gene expression pattern in cancer cells differ significantly from their normal counter parts, owing to mutations in oncogenes and tumor suppressor genes, their downstream targets, or owing to increased proliferation, and altered apoptotic potential. Various microarray based t ...