Effect of Recombinant Human Thrombopoietin (rhTPO) on Long-term Hematopoietic Recovery in Mice with Acute Radiation Sickness and Relative Mechanism / 中国实验血液学杂志

OBJECTIVE@#To investigate the effect and relative mechanism of Recombinant Human Thrombopoietin (rhTPO) on long-term hematopoietic recovery in mice with acute radiation sickness.@*METHODS@#Mice were intramuscularly injected with rhTPO (100 μg/kg) 2 hours after total body irradiation with 60Co γ-rays (6.5 Gy). Moreover, six months after irradiation, peripheral blood, hematopoietic stem cells (HSC) ratio, competitive transplantation survival rate and chimerization rate, senescence rate of c-kit+ HSC, and p16 and p38 mRNA expression of c-kit+ HSC were detected.@*RESULTS@#Six months after 6.5 Gy γ-ray irradiation, there were no differences in peripheral blood white blood cells, red blood cells, platelets, neutrophils and bone marrow nucleated cells in normal group, irradiated group and rhTPO group (P>0.05). The proportion of hematopoietic stem cells and multipotent progenitor cells in mice of irradiated group was significantly decreased after irradiation (P<0.05), but there was no significant changes in rhTPO group (P>0.05). The counts of CFU-MK and BFU-E in irradiated group were significantly lower than that in normal group, and rhTPO group was higher than that of the irradiated group(P<0.05). The 70 day survival rate of recipient mice in normal group and rhTPO group was 100%, and all mice died in irradiation group. The senescence positive rates of c-kit+ HSC in normal group, irradiation group and rhTPO group were 6.11%, 9.54% and 6.01%, respectively (P<0.01). Compared with the normal group, the p16 and p38 mRNA expression of c-kit+ HSC in the irradiated mice were significantly increased (P<0.01), and it was markedly decreased after rhTPO administration (P<0.01).@*CONCLUSION@#The hematopoietic function of mice is still decreased 6 months after 6.5 Gy γ-ray irradiation, suggesting that there may be long-term damage. High-dose administration of rhTPO in the treatment of acute radiation sickness can reduce the senescence of HSC through p38-p16 pathway and improve the long-term damage of hematopoietic function in mice with acute radiation sickness.

Thrombopoietin is associated with a prognosis of gastric adenocarcinoma

SUMMARY OBJECTIVE Thrombopoietin (THPO) is well-known as a megakaryocyte growth and development factor (MGDF) involved in megakaryocyte proliferation and maturation. To explore the biological effects of THPO in gastric adenocarcinoma, we conducted this study. Methods: By accessing the TCGA database, the expression level of THPO was determined in tumor tissues. The association between THPO expression and clinical features, or prognostic significance was described by Cox regression analysis and Kaplan-Meier. The SiRNA method was used to decline the THPO expression; then cell viability, invasion, and migration were detected to verify the effects of the knockdown of THPO. qPCR and western blotting were implemented to examine the expression level of THPO. Results: The expression of THPO was increased in tumor tissue and cells, its high-regulation was associated with a poor prognosis in patients with gastric adenocarcinoma. Cell viability, invasion, and migration were suppressed in AGS with the down-regulation of THPO. Furthermore, on the basis of si-THPO transfection, E-cadherin was promoted while N-cadherin and Vimentin were attenuated. CONCLUSION Our results revealed that THPO may be a potent marker of gastric adenocarcinoma, providing a novel potential screening method for gastric adenocarcinoma.

RESUMO OBJETIVO Trombopoetina (THPO) é um conhecido fator de desenvolvimento e crescimento megacariócito (MGDF) envolvido na proliferação e maturação de megacariócitos. Realizamos este estudo para explorar os efeitos biológicos do THPO no adenocarcinoma gástrico. Metodologia: O nível de expressão do THPO em tecidos tumorais foi determinado acessando a banco de dados TCGA. A associação entre a expressão de THPO e características clínicas ou relevância no prognóstico foi descrita através da análise de Kaplan-Meier e regressão de Cox. O método SiRNA foi utilizado para reduzir a expressão da THPO e, em seguida, a viabilidade, invasão, e migração celular foram detectadas para verificar os efeitos da redução do THPO. qPCR e western blotting foram utilizados para examinar o nível de expressão do THPO. Resultados: A expressão do THPO estava aumentada em tecido e células tumorais, esse aumento estava associado com um prognóstico negativo para pacientes com adenocarcinoma gástrico. A invasão e migração celular foram suprimidos em AGS com a redução do THPO. Além disso, com base na transfecção de si-THPO, a E-caderina foi promovida, enquanto a N-caderina e Vimentina foram atenuadas. Conclusão nossos resultados demonstram que o thpo pode ser um potente marcador de adenocarcinoma gástrico, com potencial para ser um novo tipo de triagem para adenocarcinoma gástrico.

Thrombocytosis in childhood.

Thrombocytosis is a frequent finding in hemograms obtained from hospitalized and ambulatory children due to the widespread use of automated blood cell counters. Pediatricians are commonly puzzled in cases of thrombocytosis to determine the underlying cause and the need for therapy. The purpose of this review is to assist the general pediatrician into dealing with this common hematological finding in every day clinical practice. Fortunately, primary thrombocytosis or essential thrombocythemia, a clonal disease, is exceedingly rare in childhood, but may be associated with thromboembolic and hemorrhagic complications. On the other hand, secondary or reactive thrombocytosis is very common and is due to a variety of conditions, such as acute and chronic infections, iron deficiency, bleeding, hemolytic anemias, collagen vascular diseases, malignancies, drugs and splenectomy. Treatment of reactive thrombocytosis should be directed to the underlying problem alone. Administration of platelet aggregation inhibitors such as aspirin is unwarranted. Consultation is necessary only for the rare child with extreme thrombocytosis who has clinical and/or laboratory criteria consistent with essential thrombocythemia, or in whom a hemorrhagic or thrombotic complication has developed.