Search

Cyclooxygenase inhibitors (COX) are a complex group of pharmacological compounds characterized by significant efficacy in chemoprevention of epithelial origin tumors, especially colorectal ones. It was found that inducible isoform of COX - COX-2 plays an important role in cancer growth and dissemination, e.g., by increase of cellular proliferation, reduction of apoptosis, promotion of local invasiveness and angiogenesis. COX inhibitors decrease prostaglandins' synthesis, but COX-independent mechanisms of their preventive and therapeutical activity were also proven. The influence of COX inhibitors on growth of esophageal squamous cell carcinoma and its precursor lesions was not completely clear. Most studies based on human cancer cell lines revealed antiproliferative and proapoptotic ability of both nonselective (previously called non-steroidal antiinflammatory drugs--NSAIDs) and selective COX-2 inhibitors (coxibs). In in vivo studies performed on animals exposed to chemical carcinogens, the chemopreventive effect was achieved exclusively after administration of experimental selective COX-2 inhibitors, but in the only human trial, supplementation of selective COX-2 inhibitor--celecoxib turned out ineffective. However, many epidemiological data proved effect of prolonged administration of nonselective COX inhibitors, especially acetylsalicylic acid on decreased risk of esophageal squamous cell carcinoma. Few reports concerning application of selective COX-2 inhibitors in patients with invasive squamous cell carcinoma are insufficient for ultimate evaluation of this method of therapy.

Routine examinations during chemotherapy containing anthracyclines evaluate heart function before treatment and monitor cardiotoxic effects during and after therapy. A number of methods are useful in cardiac assessment, including electrocardiography, radiology techniques (RTG, CT, MRI,PET-CT, PET-MRI), echocardiography, radioisotope imaging techniques (scintigraphy, MUGA,PET), and ultra-structure evaluation in biopsy samples. Nevertheless, there is a continuous need for new methods to predict future damage at the initial stages of cardiac changes. In recent years the therapeutic usefulness of biochemical blood parameters in anthracycline-treated patients has been assessed. The levels of cardiac troponins (cTnI, cTnT), natriuretic peptides (ANP, BNP), and endothelin 1 have been included in the studies. Heart-type fatty acid binding protein (H-FABP) is another promising factor showing cardiomyocytic impairment. However, the clinical use of biochemical parameters in diagnosing anthracycline-related cardiotoxicity is still a controversial issue.