Summary:
In the course of 55 years of its existence clinical chemotherapy succeeded in curing some types of
leukaemia, aggressive lymphomas and some patients with some solid tumours. Other patients
with solid tumours, due to treatment with cytostatics, hormones and immunomodulators, survive
longer and have a better quality of life. Further improvement of results of medical treatment of
solid tumours may be foreseen from new classical cytostatics, hormones and immunomodulators
and better use of known cytostatics. Liposomal forms of cytostatics are at least equally effective
and less toxic than original classical cytostatics.Pegylated forms of cytostatics are more suitable
for patients and and will be probably more effective than non-pegylated foms. Rational approaches to treatmet inhibiting angiogenesis and transduction of signals in tumour cells reduce the
proliferation of tumour cells and achieve remission of the neoplastic disease. Inhibition of cytoplasmic tyrosine kinases and tyrosine kinases of growth factor receptors reduces also the proliferation activity of tumour cells and some clinical studies provide evidence of their effectiveness in
the treatment of human tumours. Inhibitors of cycline dependent kinases stop the movement of
tumour cells across some stages of the cellular cycle and thus inhibit their proliferation. Inhibi-
tors of pharanesyl transferase prevent the activation of ras oncogenes, the formation of pharnesyl
isoprenoid and its incorporation into Rh0 proteins, interfere with actin regulation, adhesion and
proliferation of cells. These new drugs are less toxic than cytostatics and have a cytostatic as well
as cytocidal effect. Their effectiveness is manifested by stabilization or slight regression of the
tumour. To achieve an effect long-term treatment with an optimal dose is necessary which is not
necessarily identical with the maximum tolerated dose and after discontinuation of treatment
a relapse occurs. Combination of new inhibitors of cell division with classical cytostatics enhances the effectiveness of treatment. In the immunotherapy of tumours monoclonal antibodies are
most important which have their own antitumourous activity and increase the effectiveness of
cytostatics. Vaccines, similarly as gene therapy and modulators of resistance to cytostatics have so far limited indications. Rationally prepared molecules of new substances acting on new objectives of proliferation of tumour cells have a great chance to improve the results of treatment of
tumours.
Key words:
Chemotherapy - Inhibitors of angiogenesis -Inhibitors of pharnesyl transferase - Inhi-
bitors of tyrosine kinase - Immunotherapy - New cytostatics
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