The human proto-oncogene STAT3 encodes transcriptional factor that is essential for embryo- genesis, proliferation and differentiation of many cell types, in addition to organ regeneration and involu- tion. It also regulates innate and adaptive immune mechanisms, including B cell maturation. Augmented STAT3 activation has been found in both irreversibly committed B cell lineage precursors and plasmacy- tes. Abnormal STAT3-mediated signal transduction has been observed in a large number of neoplasms, in which it induces anti-apoptotic and cell cycle progression mediating genes transcription.

Non-proteinaceous inhibitors of the cyclin-dependent kinases

The cell cycle is regulated by the activity of cyclin dependent kinases (CDKs) associated with cyclins. Their activity is opposed by various CDK inhibitory proteins. Disregulation of the cell cycle occurs in various pathological conditions - the most important of them being cancer. Therefore, there is a continuous effort to search for chemical CDK inhibitors, which may be used as antiproliferative drugs. Various compounds have been already isolated and synthesized (e.g. olomoucin, roscovitine, flavopiridol and indirrubin). All known CDK inhibitors compete with ATP in the binding with CDKs.

The Editorial Board
Andrzej Łukaszyk - przewodniczący, Zofia Bielańska-Osuchowska, Szczepan Biliński, Mieczysław Chorąży, Aleksander Koj, Włodzimierz Korochoda, Leszek Kuźnicki, Aleksandra Stojałowska, Lech Wojtczak

Editorial address:
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