前沿科技及其它

Chemotherapy induces injury to tumor cells, which subsequently die by a number of processes. One of those processes is apoptosis, and its measurement can be a useful tool to understanding the mechanisms of action of chemotherapy agents, drug resistance, and tumor biology. Cells undergoing a ...

Induction of tumor cell death by chemotherapeutic modalities often occurs in a cell cycle-dependent manner. It has also been observed that several regulatory proteins involved in tumor chemosensitivity and apoptosis are expressed periodically during the cell cycle progres sion. ...

The study of DNA damage at the chromosome level is an essential part of genetic toxicology because chromosomal mutation is an important event in carcinogenesis. The micronucleus assays have emerged as one of the preferred methods for assessing chromosome damage because they enable both c ...

Ceramide is a bioactive lipid involved in the induction of apoptosis and is the precursor to several sphingolipids, including sphingomyelin, the gangliosides, and sphingosine. Ceramide production is increased in response to stress and toxic agents. Because modulation of ceramide ...

The measurement of functional and phenotypic P-glycoprotein by flow cytometry is suitable for cells in suspension, and is particularly appropriate for blood and bone marrow cells. We describe a functional assay for P-glycoprotein using rhodamine 123, an assay for daunorubicin accum ...

Laser flow cytometry has been used for monitoring cellular retention of fluorescent drugs such as fluorescent anticancer antibiotics (e.g., doxorubicin) and fluorochromes used for the detection of cellular drug efflux and resistance (e.g., rhodamine 123, Hoechst 33342). Multi para ...

Drug resistance of tumor cells is recognized as the primary cause of failure of chemotherapeutic treatment of most human tumors. Although pharmacological factors-including inadequate drug concentration at the tumor site-can contribute to clinical resistance, cellular fact ...

Recurring chromosomal abnormalities are associated with distinct subtypes of leukemia or lymphoma that have unique morphologic, immunophenotypic, and clinical features, such as response to therapy (1–4). Thus, cytogenetic analysis of an individual’s malignant cells plays a ma ...

Genitourinary malignancies were diagnosed in over 250,000 U.S. men and women in the year 2000, and carcinomas of the prostate, kidney and urothelium accounted for over 20% of all adult malignancies (1). In the twenty-first century, oncologists and molecular biologists will be challenged to ex ...

Differential display is a reverse-transcription polymerase chain reaction (RT-PCR) technique that was introduced in 1992 by Liang and Pardee (1). In this technique, messenger RNA 3′ termini are amplified using an anchored oligo-dT primer and a series of arbitrary 13-mers; a single round of cD ...

Serial Analysis of Gene Expression (SAGE) is a sequence-based approach that enables the comprehensive and quantitative analysis of gene expression within any cell type or tissue (1). The method is based on three main principles. First is the generation of a single 10-bp ‘tag’ sequence that cont ...

Alterations leading to inactivation of tumor suppressor genes are often associated with reduced levels of tumor suppressor gene expression. Specific tumors or cell lines may exhibit deletion of one or both gene copies, promoter methylation, splice-site mutations, nonsense mutat ...

Cell division is tightly controlled by both positive and negative growth factors. Disruption of this balance leads to the onset of neoplasm (1). For example, a group of proteins, mostly encoded by oncogenes, act as positive factors to promote cell growth and proliferation. Tumor suppressor ge ...

The subject of the present chapter is the genetic suppressor element (GSE) methodology, a functional genomics platform for identifying and characterizing genes involved in different cellular phenotypes, and the applications of this methodology to the study of tumor suppressor ge ...

Apoptosis has become a subject that draws tremendous attention and research efforts in the cancer field, since it has a major impact on tumor initiation, progression, and metastasis. At various stages during the course of tumor development, cells are subjected to stressful conditions that ...

The technique of representational difference analysis (RDA) allows the selective amplification of DNA fragments that differ greatly in abundance between two samples. The method was originally developed by Lisitsyn and co-workers for detecting differences between complex ge ...

Loss of genetic material accumulates during tumor development as cancer cells select for the physical removal or functional inactivation of genes whose encoded proteins regulate normal cellular behavior. The hallmark indication for this type of gene, now termed a tumor suppressor ge ...

The involvement of tumor suppressor genes (TSG) in cancer initiation and progression is well documented in several tumor types such as colon (APC, p53) and breast (BrcA1, BrcA2) cancers. Loss of heterozygosity of distinct chromosomal regions, which are thought to harbor as yet unidentified ...

During the last part of the twentieth century, research on human cancer increasingly focused on the molecular basis of this disease. These studies have identified many facets of cellular transformation, including aberrant cell cycle regulation, inhibition of programmed cell death or ...

Wilms’ tumor of the kidney (WT) is the most common solid tumor of childhood, and it was first described in detail by Max Wilms’ in 1899. WT is a paradigm of childhood cancer, because it has served as a model from four distinct perspectives. First, it was one of three tumors used by Knudson in the early 1970s as a model for und ...