Inhibition of RhoA/ROCK signalling pathway activity improves neural damage and cognitive deficits in the fluorosis model.

Excessive fluoride intake poses health risks to humans and animals. Many studies have indicated that fluoride exposure can damage the cytoskeleton and synapses, which has negative effects on the intellectual development of humans and animals. Our previous study suggested that the RhoA/ROCK signalling pathway is activated by NaF exposure in HT-22 cells and plays a vital role in cytoskeletal assembly and synaptogenesis. However, the mechanism underlying RhoA/ROCK-mediated cytoskeletal injury induced by fluoride remains unclear. In this study, Neuro-2A cells and ICR mice were used to investigate the effects of RhoA/ROCK activation inhibition on NaF-induced synaptic dysfunction and cognitive impairment. We detected the expression of GAP, RhoA, ROCK1/2, and (p)-MLC in vivo and in vitro model. The results showed that NaF exposure activated the RhoA/ROCK/MLC signalling pathway. We measured the effects of RhoA/ROCK inhibition on synaptic injury and intellectual impairment induced by NaF exposure. In vitro, Y-27632 suppressed activated RhoA/ROCK, attenuated morphological and ultrastructural damage, and decreased the survival rate and synapse-functional protein expression caused by NaF. In vivo, the results showed that the RhoA/ROCK/MLC pathway was inhibited by fasudil and improved pathological damage in the hippocampus, cognitive impairment, and decreased expression of neurofunctional proteins induced by NaF. Overall, these results suggest that fasudil and Y-27632 can reverse neurotoxicity caused by fluoride exposure. Furthermore, inhibition of RhoA/ROCK may be a future treatment for CNS injury, and more detailed studies on other neurodegenerative disease models are required to confirm its effectiveness.

Knockout of BRCC3 aggravates acute GVHD in allogeneic hematopoietic stem cell transplant recipient mice / 中华放射医学与防护杂志

Objective:To investigate the effect and underlying mechanism of BRCC3 knockout on acute GVHD(aGVHD) of mice.Methods:A total of 12 recipient C57BL/6J mice were divided into two groups, including 6 wild type(WT) and BRCC3 -/-(KO). The recipients were exposed to 4.5 Gy + 4.5 Gy 60Co γ-rays in total body irradiation (TBI) at 30 min intervals. At 6 h post-irradiation, 1×10 7bone marrow cells and 8×10 6 splenocytes from BALB/c mice were infused into C57BL/6J mouse via tail vein to develop aGVHD mouse model. BRCC3 was specifically knocked out in aGVHD mouse model. The organ damage was examined through histopathology. The levels of serum cytokines were measured by enzyme-linked immuno sorbent assay (ELISA) and cytometric bead array (CBA), respectively. Spleen, liver and small intestine lymphocytes were isolated at 9 d post-transplantation, and the infiltration and activation of T cells in the target organs were assayed using flow cytometry. Results:The absence of BRCC3 in recipient mice significantly shortened survival ( P<0.05) with increased liver injury of aGVHD mice. In BRCC3 -/-recipient mice, the proportions of CD8+ T cells and CD8+ CD25+ T cells were significantly higher than those in the spleen( t=6.53, 5.52, P<0.05), and the proportions of CD8+ T cells and CD8+ CD25+ T cells were significantly increased in the liver ( t=3.74, 3.19, P<0.05). Similarly, the proportions of CD8+ T cells, CD8+ CD25+ T cells and CD8+ CD69+ T cells were significantly elevated in the small intestine ( t=3.52, 4.06, 3.29, P<0.05). Conclusions:BRCC3 deletion increased the proliferation and activation of donor CD8+ T cells and aggravated aGVHD, which might provide a new prevention and treatment target for aGVHD.

Case Report: Combination Therapy With PD-1 Blockade for Acute Myeloid Leukemia After Allogeneic Hematopoietic Stem Cell Transplantation Resulted in Fatal GVHD.

Background: Azacitidine is commonly used in the treatment of relapsed acute myeloid leukemia (AML) and myelodysplastic syndrome (MDS) after allogeneic hematopoietic stem cell transplantation (allo-HSCT), but the effectiveness of this monotherapy is still very low. A possible mechanism of resistance to hypomethylating agents (HMAs) is the upregulation of the expression of inhibitory checkpoint receptors and their ligands, making the combination of HMAs and immune checkpoint blockade therapy a rational approach. Although the safety of anti-programmed cell death protein (PD)-1 antibodies for patients with post-allo-HSCT remains a complicated issue, the preliminary clinical result of combining azacitidine with anti-PD-1 antibodies is encouraging; however, the safety and efficacy of this approach need further investigation. Case Presentation: We reported a case of treated secondary (ts)-AML in a patient who received tislelizumab (an anti-PD-1 antibody) in combination with azacitidine. The patient relapsed after allo-HSCT and was previously exposed to HMAs-based therapy. The patient received tislelizumab for compassionate use. After the combination treatment, the patient achieved complete remission with incomplete hematologic recovery, negative minimal residual disease (MRD) by flow cytometry (FCM), and negative Wilms' tumor protein 1 (WT1). However, the patient successively developed serious immune-related adverse events (irAEs) and graft vs. host disease (GVHD) and eventually died from complications of GVHD. Conclusion: To our knowledge, this is the first case to report the combined use of tislelizumab and azacitidine to treat relapsed AML posttransplantation. This report highlights the safety concerns of using an anti-PD-1 antibody in combination with azacitidine after allo-HSCT, especially the risk of GVHD, and provides a basis for future studies.

Donor-Derived CD123-Targeted CAR T Cell Serves as a RIC Regimen for Haploidentical Transplantation in a Patient With FUS-ERG+ AML.

Background: Allogeneic hematopoietic stem cell transplantation (allo-HSCT) following chemotherapy is part of standard treatment protocol for patients with acute myeloid leukemia (AML). FUS-ERG+ AML is rare but has an extremely poor prognosis even with allo-HSCT in remission, possibly due to its a leukemia stem cell (LSC)-driven disease resulting in chemotherapy resistance and a novel therapy is urgently required. It has been reported that FUS-ERG-positive AML expresses CD123, a marker of LSC, in some cases. CD123-targeted CAR T cell (CART123) is promising immunotherapy, but how to improve the complete remission (CR) rate and rescue potential hematopoietic toxicity still need to explore. Case Presentation: We used donor-derived CART123 as part of conditioning regimen for haploidentical HSCT (haplo-HSCT) in a patient with FUS-ERG+ AML who relapsed after allogeneic transplantation within 3 months, resists to multi-agent chemotherapy and donor lymphocyte infusion (DLI) and remained non-remission, aiming to reduce these chemotherapy-resistant blasts and rescue potential hematopoietic toxicity. The blasts in BM were reduced within 2 weeks and coincided with CAR copies expansion after CART123 infusion. The patient achieved full donor chimerism, CR with incomplete blood count recovery, and myeloid implantation. Conclusion: Our results hints that CART123 reduces the chemotherapy-resistant AML blasts for FUS-ERG+ AML without affecting the full donor chimerism and myeloid implantation.

Granulocyte colony-stimulating factor-primed bone marrow: an excellent stem-cell source for transplantation in acute myelocytic leukemia and chronic myelocytic leukemia / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Steady-state bone marrow (SS-BM) and granulocyte colony-stimulating growth factor-primed BM/peripheral blood stem-cell (G-BM/G-PBSC) are the main stem-cell sources used in allogeneic hematopoietic stem-cell transplantation. Here, we evaluated the treatment effects of SS-BM and G-BM/G-PBSC in human leucocyte antigen (HLA)-identical sibling transplantation.</p><p><b>METHODS</b>A total of 226 patients (acute myelogenous leukemia-complete remission 1, chronic myelogenous leukemia-chronic phase 1) received SS-BM, G-BM, or G-PBSC from an HLA-identical sibling. Clinical outcomes (graft-versus-host disease [GVHD], overall survival, transplant-related mortality [TRM], and leukemia-free survival [LFS]) were analyzed.</p><p><b>RESULTS</b>When compared to SS-BM, G-BM gave faster recovery time to neutrophil or platelet (P < 0.05). Incidence of grade III-IV acute GVHD and extensive chronic GVHD (cGVHD) was lower than seen with SS-BM (P < 0.05) and similar to G-PBSC. Although the incidence of cGVHD in the G-BM group was similar to SS-BM, both were lower than G-PBSC (P < 0.05). G-BM and G-PBSC exhibited similar survival, LFS, and TRM, but were significantly different from SS-BM (P < 0.05). There were no significant differences in leukemia relapse rates among the groups (P > 0.05).</p><p><b>CONCLUSIONS</b>G-CSF-primed bone marrow shared the advantages of G-PBSC and SS-BM. We conclude that G-BM is an excellent stem-cell source that may be preferable to G-PBSC or SS-BM in patients receiving HLA-identical sibling hematopoietic stem-cell transplantation.</p>

Therapeutic effect of CY-fTBI and BMM conditioning regimen in the process of allo-HSCT treating Ⅲ,Ⅳ non-Hodgkin lymphoma: 15 years analysis of single-center / 中华血液学杂志

<p><b>OBJECTIVE</b>To investigate the efficacy of allogeneic hematopoietic stem cell transplantation（allo-HSCT）in the treatment of patients with Ⅲ,Ⅳ non-Hodgkin lymphoma（NHL）, and compared the efficacy between Cy- fractionated to talbody irradiation（fTBI）based conditioning regimen and Maryland, horse flange and mitoxantrone（BMM）.</p><p><b>METHODS</b>The clinical data of 47 patients with Ⅲ, Ⅳ NHL after allo- HSCT from November 1998 to May 2014 were collected and retrospectively analyzed. To observe the hematopoietic reconstruction recovery after transplantation, cumulative incidence of acute graft- versus- host- disease （aGVHD） and chronic graft- versus- host- disease （cGVHD）, transplantation related mortality （TRM）, recurrence rate （RR）, disease- free survival （DFS）, overall survival（OS）. Compare the efficacy of fTBI and BMM conditioning regimen at the same time.</p><p><b>RESULTS</b>Neutrophils achieving 0.5×10⁹/L and platelets achieving 50×10⁹/L on day 17 （range, 10- 72） post transplantation. Acute GVHD occurred in 53.19%, among them, grade Ⅰ-Ⅱ occurred in 42.55%, grade Ⅲ-Ⅳ occurred in 10.65%, and cGVHD occurred in 21.28%. 21 patients were alive with a median follow up of 9.7 months（0.2-149.1 months）. Overall survival（OS）was 73.5%, 49.3%, 40.1% respectively in the first, third and fifth year in Cy-fTBI group; in BMM group it was 67.8%, 32.9% and 31.4% respectively, and disease-free survival（DFS）was 65.3%, 45.6%, 30.2% respectively in the first, third and fifth year. In Cy-fTBI group, the recurrence rate（RR）and transplantation related mortality（TRM）in the first year were 18.9%, 23.0% respectively, the third year were 19.5%, 38.3% and the fifth year were 35.2%, 39.2%. In BMM group, RR and TRM in the first year were 27.4%, 24.5% respectively, the third year were 38.9%, 46.4% and the fifth year were 39.2%, 48.2%. However, there was no significant difference in the indicator of OS, DFS, RR, TRM in the two groups.</p><p><b>CONCLUSION</b>Allo-HSCT could make some Ⅲ,Ⅳ NHL patients achieve long-term disease- free survival, but the TRM was still high relatively. Moreover, compared with the program of BMM conditioning regimen, Cy-fTBI might reduce the TRM and RR, meanwhile, increase the DFS and OS. However, due to the small number cases of two groups, there was no statistical significant difference.</p>