Unrelated donor umbilical cord blood transplant versus unrelated hematopoietic stem cell transplant in patients with acute leukemia: A meta-analysis and systematic review

Effect of Hematopoietic Stem Cell Transplantation Regimen on Tacrolimus Pharmacokinetics

Objectives

Treatment with tacrolimus requires strict control of the whole-blood concentration in patients undergoing allogeneic hematopoietic stem cell transplantation (HSCT). In patients undergoing cord blood transplantation (CBT), there is a negative correlation between volume of distribution of tacrolimus and hemoglobin levels, which reflect the red blood cell (RBC) count. In this study, we evaluated the influence of the conditioning regimen (myeloablative and reduced-intensity conditioning) or donor source (cord blood, bone marrow, and peripheral blood stem cells) on the pharmacokinetics of tacrolimus in patients undergoing HSCT, including those undergoing CBT. We also examined applicability of dosing strategy of tacrolimus considering the RBC count.

Methods

We retrospectively analyzed clinical data-including whole-blood tacrolimus concentrations-from patients with HSCT. The observation period spanned from first continuous intravenous infusions until switch to oral medication, transfer to another hospital, relapse, or death. Population pharmacokinetic analysis was performed on whole-blood tacrolimus concentrations obtained from therapeutic drug monitoring during the observation period. Patient characteristics and laboratory data were evaluated as covariates.

Results

We enrolled 91 patients undergoing HSCT (CBT: n = 56; bone marrow transplantation: n = 22; and peripheral blood stem cell transplantation: n = 13); 58 and 33 patients received myeloablative conditioning and reduced-intensity conditioning, respectively. Whole-blood tacrolimus concentrations were accurately captured (n = 1,658 measurements) using a one-compartment and additive error model. The conditioning regimen and donor source did not have an impact on the pharmacokinetics of tacrolimus. Therefore, these factors were not considered when forming the dosing strategy. Nevertheless, a negative correlation between volume of distribution and hemoglobin level was confirmed, indicating that monitoring the RBC count is useful in assessing the dosing strategy.

Conclusions

A tacrolimus dosing strategy that considers the variability in hemoglobin levels applies to all patients undergoing HSCT.

Intrabone infusion for allogeneic umbilical cord blood transplantation in children

Umbilical cord blood transplantation (UCBT) has been used to treat malignant and non-malignant diseases. UCBT offers the advantages of easy procurement and acceptable partial HLA mismatches, but also shows delayed hematopoietic and immunological recoveries. We postulated that an intrabone (IB) infusion of cord blood could provide a faster short- and long-term engraftment in a pediatric population with malignant and non-malignant hematologic diseases. We conducted this phase I-II single arm, exploratory clinical trial (NCT01711788) from 2012 to 2016 in a single center. Fifteen patients aged from 1.9 to 16.4 years received an IB UCBT. Median time to neutrophils and platelet recoveries were 18 days (range: 13-36 days) and 42 days (range: 26-107 days), respectively. Rate of severe acute GVH grade was low, with only one patient with grade III aGVH. Relapse occurred in 5 patients (38.5%) and TRM occurred in 1 patient. This leads to 6 years EFS and OS of 66.7% and 80% respectively. In conclusion, IB UCBT is safe and well-tolerated in children and hematological recovery compared similarly to the results obtained with IV UCBT.

Effects of signaling pathway inhibitors on hematopoietic stem cells

While there are numerous small molecule inhibitory drugs available for a wide range of signalling pathways, at present, they are generally not used in combination in clinical settings. Previous reports have reported that the effects of glycogen synthase kinase (GSK)3β, p38MAPK, mTOR and histone deacetylase signaling combined together to suppress the stem-like nature of hematopoietic stem cells (HSCs), driving these cells to differentiate, cease proliferating and thereby impairing normal hematopoietic functionality. The present study aimed to determine the effect of HDACs, mTOR, GSK-3β and p38MAPK inhibitor combinations on the efficient expansion of HSCs using flow cytometry. Moreover, it specifically aimed to determine how inhibitors of the GSK3β signaling pathway, in combination with inhibitors of P38MAPK and mTOR signaling or histone deacetylase (HDAC) inhibitors, could affect HSC expansion, with the goal of identifying novel combination strategies useful for the expansion of HSCs. The results indicated that p38MAPK and/or GSK3β inhibitors increased Lin⁻ cell and Lin⁻Sca-1⁺c-kit⁺ (LSK) cell numbers in vitro. Taken together, these results suggested that a combination of p38MAPK and GSK3β signaling may regulate HSC differentiation in vitro. These findings further indicated that the suppression of p38MAPK and/or GSK3β signalling may modulate HSC differentiation and self-renewal to enhance HSC expansion.

Umbilical cord blood stem cells transplantation as an adjunctive treatment strategy for liver cirrhosis in Chinese population: a meta-analysis of effectiveness and safety

Objective

The aim of the study was to evaluate the efficacy and safety of umbilical cord blood stem cells (USCs) transplantation combined with routine supportive therapy (RST) for liver cirrhosis (LC).

Materials and methods

Clinical trials involved in this research were searched from Web of Science, PubMed, EMBASE, Cochrane Library, Wanfang and CNKI database. Treatment effects, quality of life (QoL), adverse events and other outcome measures were extracted and evaluated.

Results

A total of 10 trials including 616 LC patients were involved in this study. Based on our analysis, the liver function of LC patients was significantly improved after USCs transplantation and RST combined therapy, indicated by decreased total bilirubin, alanine aminotransferase, aspartate aminotransferase levels and prothrombin time and increased serum albumin level and prothrombin activity. Compared to those treated by RST alone, patients treated by combined therapy showed more satisfied treatment effects, improved QoL reflected by improved appetite (odds ratio [OR]=5.43, 95% CI=2.84 to 10.38, P<0.00001) and relieved fatigue (OR=4.33, 95% CI=0.87 to 21.60, P=0.07), ascetic fluid (OR=4.56, 95% CI=2.69 to 7.74, P<0.00001), abdominal distension (OR=4.01, 95% CI=1.34 to 12.02, P=0.01) and edema (OR=2.69, 95% CI=0.23 to 31.72, P=0.43). No serious adverse events occurred during USCs therapy.

Conclusion

USCs transplantation is a safe and effective adjuvant therapy for RST-treated LC, possibly through improving patients’ liver function.