Stem cell mobilization after coronary artery bypass grafting.

BACKGROUND: Recently, the role of stem cells as a potential therapeutic tool for ischemic heart disease has been evaluated by a number of experimental and clinical studies. Although preliminary clinical data appear to be promising, the precise pathophysiological role of stem cell mobilization during acute myocardial ischemia remains uncertain. The present study was aimed at assessing factors affecting stem cell mobilization after coronary artery bypass grafting used as a clinical model of controlled myocardial ischemia. METHODS: Eighteen patients (16 men, 2 women, mean age 66 +/- 8 years) with three-vessel coronary artery disease undergoing coronary artery bypass grafting were included in the study; 24 age- and sex-matched healthy subjects served as controls. On admission, 10 patients had stable angina and 8 had unstable angina. Clinical history and instrumental evidence of previous myocardial infarction were present in 11 patients. Venous peripheral blood was sampled at baseline and 6, 24, 48 and 72 hours after coronary surgery. Duration of cardiac arrest and extracorporeal circulation were recorded as well as the release of total creatine kinase (CK), CK-MB, troponin I and C-reactive protein. CD34+ stem cells were analyzed by flow cytometry according to published methods. RESULTS: In patients with ischemic heart disease the peripheral concentration of CD34+ cells was higher than that of control subjects (0.202 +/- 0.30 vs 0.068 +/- 0.059%, p = 0.03). However, patients with stable and unstable angina had similar concentration of CD34+ cells (0.171 +/- 0.33 vs 0.241 +/- 0.275%, p = 0.63) as well as patients with and without previous myocardial infarction (0.134 +/- 0.19 vs 0.245 +/- 0.352%, p = 0.4). Coronary artery bypass grafting caused a non-significant increase in concentration of CD34+ cells at 24 hours which was similar in patients with stable and unstable angina. Finally, no significant correlation was found between peripheral concentration of CD34+ cells and aortic clamping and extracorporeal circulation duration, peak release of total CK, CK-MB, troponin I and C-reactive protein. CONCLUSIONS: Peripheral concentration of CD34+ stem cells is higher in patients with ischemic heart disease than in healthy controls but it is similar in patients with stable and unstable coronary syndromes. Peripheral mobilization of CD34+ cells is not correlated with the duration and severity of ischemic insult induced by surgical cardiac arrest. These preliminary findings suggest that CD34+ cell mobilization may be modulated more by tonically active than phasic factors

Complex and multifaceted therapy-related myeloid neoplasm following laryngeal cancer treated with Cisplatin and radiotherapy

Therapy-related myeloid neoplasm, usually in the forms of myelodysplastic syndromes/acute myeloid leukemias (t-MDS/AML), are well-known secondary malignancies occurring in cancer patients who received chemo-radiotherapy regimens, especially those including alkylating agents and topoisomerase II inhibitors.1 The leukemogenic potential of other compounds, such as platinum drugs, is less clearly established,2 although a slightly increased risk of secondary AML has been reported after therapy for ovarian3 and testicular4 cancers. We describe the quite rare occurrence of a myelodysplastic/myeloproliferative neoplasm (MDS/MPN) with multiple accumulating genetic anomalies not usually found together as JAK2 V617F, IDH2 R172K and 7q- deletion, after exposure to radiotherapy and platinum based chemotherapeutic agents in a patient treated for laryngeal cancer