细胞技术

Metastatic renal cell carcinoma (RCC) is incurable and there are few treatment options that assure even a short prolongation in survival. It is the most common malignancy of the adult kidney and accounts for approximately 12,000 deaths per year (1). Due to a lack of diagnostic markers for early dete ...

The DNA damage-dependent checkpoint of Saccharomyces cerevisiae is a paradigm for eukaryotic checkpoint pathways that regulate cell cycle progression in the presence of insults to the genetic material. In order to better understand this pathway, we undertook a biochemical study of t ...

The spindle checkpoint is assayed in Saccharomyces cerevisiae using several criteria. Sensitivity to benzimidazole drugs is assayed in cells grown in liquid medium and cells grown on solid medium on petri plates. Cell cycle delays are measured using cells synchronized by treatment with ...

In response to genotoxic insults, cells activate DNA damage checkpoint pathways that stimulate DNA repair, lead to a transient cell cycle arrest, and/or elicit programmed cell death (apoptosis) of affected cells. The Caenorhabditis elegans germ line was recently established as a model s ...

In the presence of DNA damage, cells delay the entry into mitosis, presumably to allow time for repair. Methods to detect the delay of mitosis in a multicellular model organism, Drosophila melanogaster, are described here. These include the collection of embryos and larvae, irradiation with x- ...

The checkpoint protein Chfr delays entry into mitosis in the presence of mitotic stress. We have analyzed the Chfr checkpoint pathway in the Xenopus cell-free system. We showed that Chfr is a ubiquitin ligase that targets polo-like kinase (Plk1) for degradation, leading to delayed activation ...

Owing to their importance in normal cell division, DNA damage checkpoint and repair genes are often required for the earliest stages of embryonic development. For example, conventional deletion of ATR (1), Chk1 (2), Mad2 (3), NBS (4), Rad50 (5), BRCA1 (6), BRCA2 (7), or Rad51 (8) leads to developmental arr ...

Germline mutations of the breast tumor suppressor gene BRCA1 predispose women to breast and ovarian cancers. However, loss-of-function mutations of mouse Brca1 results in recessive embryonic lethality, which obscures the functions of BRCA1 in breast cancer formation. Cre-loxP-m ...

Maintenance of genomic integrity is essential to avoid cellular transformation, neoplasia, or cell death. DNA synthesis, mitosis, and cytokinesis are important cellular processes required for cell division and the maintenance of cellular homeostasis; they are governed by many ex ...

The spindle checkpoint is an evolutionarily conserved regulatory mechanism that ensures correct segregation of chromosomes at mitosis and meiosis. The kinetochore plays an integral role in spindle checkpoint signaling by integrating chromosome attachment to the spindle wi ...

The G2 checkpoint prevents cells from entering mitosis when DNA is damaged, providing an opportunity for repair and stopping the proliferation of damaged cells. Because the G2 checkpoint helps to maintain genomic stability, it is an important focus in understanding the molecular causes ...

Mitogen-dependent progression through the first gap phase (G1) of the mammalian cell-division cycle is precisely regulated so that normal cell division is coordinated with cell growth, while the initiation of DNA synthesis (S phase) is precisely ordered to prevent inappropriate amp ...

Linkage analysis has aided in the identification of genes involved in many diseases, including several cancers. It relies on using family-based data to detect genetic loci that may harbor disease predisposing genes. Although linkage studies were first designed to find the genes respons ...

The management of patients with pancreatic cancer is a multidisciplinary approach that presents enormous challenges to the clinician. Overall 5-yr survival for all patients remains

Elucidation of basic mechanisms that regulate pancreatic organogenesis may help define molecular pathways involved in the development of exocrine pancreas cancer. The zebrafish has emerged as a powerful model for genetic dissection of the mechanisms underlying vertebrate or ...

The developmental plasticity of adult pancreas is evidenced by the ability to undergo conversion between different epithelial cell types. Specific examples of such conversions include acinar to ductal metaplasia, ductal to islet metaplasia, and generation of ductal structures ...

Conventional gene targeting has been very useful in the study of gene function and regulation in mice. However, the methodologies involved have several limitations. First, mutations that cause embryonic lethality largely preclude studies of gene function at a later stage in developme ...

Multiple experimental approaches have been employed to study exocrine pancreatic cancer, including the use of animals as surrogates for the human disease. Animals have the advantage that they can be manipulated to address specific hypotheses regarding mechanisms underlying this ...

SEREX (serological analysis of recombinant tumor cDNA expression libraries) is a technique designed to isolate tumor antigens that have elicited high-titer IgG responses in human hosts. This is an immunoscreening method for gene cloning, with two key features that distinguish it from e ...

Telomerase, which ensures the unlimited proliferation by adding TTAGGG repeat at the end of the chromosome, is strongly activated at a very high incidence in a variety of malignant neoplasms including pancreatic cancer. In addition to the acquisition of the immortality, telomerase plays ...