Angiogenesis is indispensable for the growth of solid tumors and angiogenic factors are also involved in the progression of hematological malignancies. Targeting the formation of blood vessels is therefore regarded as a promising strategy in cancer therapy. Interestingly, besides demonstration of some beneficial effects of novel anti-angiogenic compounds, recent data on the activity of already available drugs point to their potential application in anti-angiogenic therapy. Among these are the statins, the inhibitors of 3-hydroxy-3-methylglutaryl-coenzyme A reductase. Statins are very efficient in the treatment of hypercholesterolemia in cardiovascular disorders; however, their effects are pleiotropic and some are not directly related to the inhibition of cholesterol synthesis. Some reports particularly highlight the pro-angiogenic effects of statins, which are caused by low, nanomolar concentrations and are regarded as beneficial for the treatment of cardiovascular diseases. On the other hand, the anti-angiogenic activities, observed at micromolar concentrations of statins, may be of special significance for cancer therapy. Those effects are caused by the inhibition of both proliferation and migration and induction of apoptosis in endothelial cells. Moreover, the statin-mediated inhibition of vascular endothelial growth factor synthesis, the major angiogenic mediator, may contribute to the attenuation of angiogenesis. It has been suggested that the anti-cancer effect of statins can be potentially exploited for the cancer therapy. However, several clinical trials aimed at the inhibition of tumor growth by treatment with very high doses of statins did not provide conclusive data. Herein, the reasons for those outcomes are discussed and the rationale for further studies is presented.
Type 2 diabetes mellitus (T2DM) is a metabolic disease caused by insulin resistance that leads to changes in glucose metabolism. Importantly, both insulin resistance and hyperglycemia are present in T2DM patients as a hallmarks of metabolic syndrome. They negatively affect functions of many cells, for example endothelial cells. Endothelial progenitor cells (EPC) is a population of mononuclear cells that expresses endothelial and progenitor markers. EPC are also characterized by ability to form tubes on matrigel, outgrowth into mature endothelial cells, produce proangiogenic factors or take part in the blood vessels formation. Upon injury endothelial progenitor cells are mobilized from bone marrow, home to injured site and take part in vessels formation. It was shown however, that functions of EPC in T2DM patients are impaired. In this review we focused on the T2DM and its detrimental effects on EPC biology. taking also into account the beneficiary role of anti-diabetic drugs. Decreased number and impaired functions of EPC in T2DM patients might lead to increased frequency of cardiovascular incidents and development of micro- or macroangiopathies.
HO-1 (haem oxygenase-1) is a ubiquitously expressed inducible enzyme degrading haem to CO, biliverdin and Fe2+. Its activation reduces oxidative stress in cells and inhibits inflammation, both due to removal of haem and because of the biological activity of HO-1 products. CO may act similarly to NO, activating soluble guanylate cyclase and elevating cGMP production. It inhibits platelet aggregation, reduces leucocyte adhesion, decreases apoptosis and lowers the production of some pro-inflammatory cytokines. Biliverdin is converted into bilirubin by biliverdin reductase, and both compounds are potent antioxidants, free radical scavengers and inhibitors of the complement cascade. Iron ions can be potentially toxic, increasing the generation of hydroxyl radicals, but simultaneous induction of ferritin and activation of the Fe-ATPase iron transporter protects cells from oxidative stress. Importantly, basal and induced expression of HO-1 is very variable in the human population because of the highly polymorphic (GT)n fragment in the promoter, which may have clinical relevance. The recognized roles of HO-1 are far beyond cytoprotection. The enzyme is important in the regulation of cell proliferation, differentiation and apoptosis. Its activity improves neovascularization, attenuates inflammation and modulates the immune response, thereby influencing carcinogenesis, wound healing, transplant survival and the progression of cardiovascular diseases. Recent results indicate that HO-1 may also act through the regulation of microRNAs, which suggests a much broader involvement of HO-1 in the modulation of cell functions and offers a potential explanation for some well-known activities whose mechanism has hitherto been unclear.
Dystrofia mięśniowa Duchenne’a (DMD) to choroba genetyczna sprzężona z chromosomem X, dotykająca w przybliżeniu 1 na 5000 urodzonych chłopców. Jest spowodowana mutacjami w genie DMD kodującym dystrofinę, która odpowiada za stabilność mechaniczną mięśni podczas skurczu. Jej brak prowadzi do postępującego osłabienia mięśni i przedwczesnej śmierci chorych w wyniku niewydolności sercowo-oddechowej. W ostatnich latach opracowano wiele eksperymentalnych terapii, których celem jest przywrócenie funkcjonalnej dystrofiny lub przeciwdziałanie procesom przyczyniającym się do postępu choroby, takim jak zapalenie czy zwłóknienie. Pomimo tego DMD wciąż pozostaje chorobą nieuleczalną, a glikokortykoidy, wykazujące wiele działań niepożądanych, nadal stanowią „złoty standard” leczenia. Aktualne jest zatem opracowywanie innowacyjnych możliwości terapeutycznych, które przynajmniej złagodzą objawy DMD. Wśród nich na uwagę zasługuje celowanie w określone mikroRNA (miR), np. miR-378a, przywrócenie prawidłowej angiogenezy oraz wykorzystanie cytoprotekcyjnych czynników takich jak oksygenaza hemowa-1 (HO-1) czy siarkowodór (H2S). W niniejszej pracy omówiono zarówno patologię choroby jak i wspomniane, nowe możliwości terapeutyczne w DMD.
The article examines the practice of cell therapies, often named as stem cell therapies. For the general public this is recognized as promising treatment for many diseases, offering hope for many people to restore health to themselves or their loved ones. However, despite the enormous potential that this type of treatment holds, it has its limitations. The tension between hope, science, truth and deception can come to the fore especially when someone is fighting for their life. Moral and ethical issues play a key role in such cases, serving as guideposts obscured, however, by information noise.
