ABSTRACT
Objective: Hemoglobinopathies such as beta-thalassemia and sickle cell disease [SCD] are inherited disorders that are caused by mutations in beta-globin chain. Gamma-globin gene reactivation can ameliorate clinical manifestations of betathalassemia and SCD. Drugs that induce fetal hemoglobin [HbF] can be promising tools for treatment of beta-thalassemia and SCD patients. Recently, it has been shown that Simvastatin [SIM] and Romidepsin [ROM] induce HbF. SIM is a BCL11a inhibitor and ROM is a HDAC inhibitor and both of these drugs are Food and Drug Administration [FDA]-approved for hypercholesterolemia and cutaneous T-cell lymphoma respectively. Our aim was to evaluate the synergistic effects of these drugs in inducing HbF
Materials and Methods: In our experimental study, we isolated CD34+ cells from five cord blood samples that were cultured in erythroid differentiation medium containing ROM and Simvastatin. Then Gamma-globin, BCL11a and HDAC gene expression were evaluated on the 7th and 14th day of erythroid differentiation by real-time polymerase chain reaction [PCR] and immunocytochemistry
Results: Our results showed that combination of SIM and ROM significantly increased Gamma-globin gene expression and inhibit BCL11a and HDAC expression compared to results of using each of them alone. SIM and ROM lead to 3.09- fold increase in HbF production compared to the control group. Also, SIM inhibited BCL11a expression [0.065-fold] and ROM inhibited HDAC1 expression [0.47-fold] as two important inhibitors of HbF production after birth
Conclusion: We propose combination therapy of these drugs may be ameliorate clinical manifestation in beta-thalassemia and SCD with at least side effects and reduce the need for blood transfusion
ABSTRACT
Multiple myeloma [MM] is a plasma cell malignancy where plasma cells are increased in the bone marrow [BM] and usually do not enter peripheral blood, but produce harmful factors creating problems in these patients [e.g. malignant plasma cells over activate osteoclasts and inhibit osteoblasts with factors like RANKL and DKK]. These factors are a main cause of bone lesion in MM patients. Recently SOST gene which responsible to encodes the sclerostin protein was identify. This protein specifically inhibits Wnt signaling in osteoblasts [inhibition of osteoblast differentiation and proliferation] and decrease bone formation and can also cause bone lesion in MM patients. In this experimental study, human myeloma cell lines [U266 b1] were purchased from Pasteur Institute of Iran. Samples consisted of BM aspirates from the iliac crest of MM patients. BM with more than 70% plasma cell were selected for our study [6 patients] and one healthy donor. RNA extraction was done with Qiagen kit. was undertaken on mRNA of samples and cell lines. Also we purchased unrestricted somatic stem cells from Bonyakhte Company to evaluate the effect of soluble factors from myeloma cell lines on osteogenic differentiation medium. Our results showed that SOST is expressed significantly in primary myeloma cells derived from MM patients and myeloma cell lines. In other words, patients with more bone problems, express SOST in their plasma cells at a higher level. In addition, myeloma cells inhibit osteoblast differentiation in progenitor cells from umbilical cord blood stem cell [UCSC] in osteogenic inducing medium. There are many osteoblast maturation inhibitory factors such as DKK, Sfrp and Sclerostin that inhibit maturation of osteoblast in bone. Among osteoblast inhibitory agents [DKK, Sfrp, Sclerostin] sclerostin has the highest specificity and therefore will have less side effect versus non-specific inhibitory agents. Our results also show that based on SOST expression in MM, there is a potential to inhibit sclerostin with antibody or alternative methods and prevent bone lesion in MM patients with the least side effect