Anesthesia Progress Blog - Part 9

Innovative Chemotherapy: Identification of New Chemotherapeutic AgentsIdentification of New Chemotherapeutic Agents
For the past 3 decades, the major strategies of preclinical testing of agents with potential anticancer activity in humans has depended on the use of mice bearing transplantable tumors (predominantly leukemias) of murine origin. This effort has utilized enormous resources of time, talent and money, and the results of screening several hundred thousand compounds have been disappointing. Relatively few useful drugs that have widespread utilization have been identified. The reasons for these results are complex, but include the failure of mouse leukemia models to correctly identify agents useful in treating human malignancies. In addition, even when such agents are identified, the type and varieties of human malignancies in which they may be utilized are not readily apparent. These experiences have led to a complete revamping of the screening process by the Developmental Therapeutics Program at the National Cancer Institute. A large number of human tumor cell lines have been grouped into disease-oriented panels and have been extensively characterized. comments
Read the rest of this entry »

Prospective Trial of Individualized Chemotherapy
While several thousand correlations have been performed between the results of in vitro testing and clinical response, relatively few properly conducted prospective clinical trials have been reported. Currently, we are more than halfivay through a prospective clinical trial based on selection of individualized therapy for patients with extensive stage SCLC.W This disease presents unusual problems as well as opportunities for such a trial. While “curative” surgical resections are seldom attempted in the USA, SCLC is often widely metastatic at diagnosis. The number of tumor cells in specimens obtained from route staging procedures are relatively small and contain many stromal cells. However, culture methods exist for the selective propagation of small numbers of tumor cells with quite acceptable success rates. Read the rest of this entry »

Innovative Chemotherapy: Investigation of the Multidrug Resistant PhenotypeInvestigation of the Multidrug Resistant Phenotype
Multidrug resistance is a common clinical problem in lung cancer. In SCLC, most tumors recurring after chemotherapy manifest this phenotype, while some demonstrate it prior to therapy. In contrast, most NSCLC and carcinoid tumors demonstrate de novo resistance. While there are many possible reasons for chemoresistance to multiple agents including those that the tumor cells have not been exposed to, one of the best studied mechanisms is over-expression of a 170,000 dalton membrane protein (F-glycoprotein) encoded by the MDRl gene. F-glycoprotein functions as an energy-dependent efflux pump, removing many (but not all) cytotoxic drugs from the cell before they can exert their cytotoxic effects. The MDRl gene is expressed as a 4.5 kb mRNA in some normal tissues, including colonic mucosa, renal proximal tubules, biliary ducts and adrenal cortex and medulla. Click Here
Read the rest of this entry »

We have focused on the semiautomatic MTT assay, a tetrazolium dye method. Large numbers of samples can be tested at many drug concentrations and the results obtained within a few days. The major disadvantage of such assays is that they are unable to discriminate between normal and tumor cells if applied to fresh tumor samples. We are attempting to adapt the assay for clinical use by combining it with short-term selective culture of tumor cells in defined media as well as differential adhesiveness. By these methods, a relatively pure tumor cell sample can be obtained within a few days. add comment
Read the rest of this entry »

Innovative Chemotherapy: In vitro Drug Sensitivity TestingIn vitro Drug Sensitivity Testing
Selection of individualized chemotherapy based on in vitro drug sensitivity testing (DST) has been a goal of clinicians for more than 3 decades. Despite intense interest and research, and the development of multiple assay methods, this goal has remained theoretic for the most part. In applying such procedures, the following points must be carefully considered: How do you test?; What do you test?; How do you interpret and apply the data?; and (most important of all), What is its clinical relevance? While a detailed discussion of these points is beyond the scope of this report, certain aspects will be considered, in particular those that impact on lung cancer. website
Read the rest of this entry »

The former results in higher take rates and rapid fatality. Of interest, the intracranial tumors selectively locate in meningeal and ventricular sites. Thus, it represents a useful model of meningeal carcinomatosis. While only a few tumors can be transplanted intraperito-neally, widespread dissemination may result, with frequent involvement of pleural and pericardial spaces. Thus, these inoculation routes may provide useful models for pleural and pericardial involvement. Other occasionally utilized sites include intrathoracic, intrasplenic and intravenous inoculations. The recently described technique of intrabron-chial inoculation offers a unique orthotopic model for studying the biology of peripheral airway tumors. other
Read the rest of this entry »

Innovative ChemotherapyXenografts and In vitro Drug Sensitivity Testing
Over 150,000 cases of lung cancer occur in the USA annually, nearly 90% of whom will die of their disease with a median life expectancy of less than 1 year. Obviously, we need both new drugs as well as new therapeutic concepts. While the latter ideas are discussed by other contributors to this issue, this report will focus on the use of animal and cell culture models for the selection of individualized chemotherapy as well as for the identification of new therapeutic agents. cialis professional
Read the rest of this entry »

Pages: Prev 1 2 3 4 5 6 7 8 9 10 ... 132 133 134 Next

About this blog

Blog invites submissions of review articles, reports on clinical techniques, case reports, conference summaries, and articles of opinion pertinent to the control of pain and anxiety in dentistry.