[Risk Factors of Late-Onset Hemorrhagic Cystitis after Allogeneic Hematopoietic Stem Cell Transplantation].

To analyze the risk factors for late-onset hemorrhagic cystitis (LOHC) after allogeneic hematopoietic stem cell transplantation (allo-HSCT), the risk factors for the progression of LOHC to severe LOHC, and the effect of LOHC on survival. METHODS: The clinical data of 300 patients who underwent allo-HSCT at the First Affiliated Hospital of Chongqing Medical University from January 2015 to December 2021 were retrospectively analyzed. The relevant clinical parameters that may affect the occurance of LOHC after allo-HSCT were selected for univariate and multivariate analysis. Then, the differences in overall survival (OS) and progression-free survival (PFS) between different groups were analyzed. RESULTS: The results of multivariate analysis showed that the independent risk factors for LOHC after allo-HSCT were as follows: age≤45 years old (P =0.039), intensified conditioning regimen with fludarabine/cladribine and cytarabine (P =0.002), albumin≤30 g/L on d30 after transplantation (P =0.007), CMV-DNA positive (P =0.028), fungal infection before transplantation (P =0.026), and the occurrence of grade Ⅱ - Ⅳ aGVHD (P =0.006). In the transplant patients who have already developed LOHC, the occurance of LOHC within 32 days after transplantation (P =0.008) and albumin≤30 g/L on d30 after transplantation (P =0.032) were independent risk factors for the progression to severe LOHC. The OS rate of patients with severe LOHC was significantly lower than that of patients without LOHC (P =0.041). CONCLUSION: For the patients aged≤45 years old and with intensified conditioning regimen, it is necessary to be vigilant about the occurrence of LOHC; For the patients with earlier occurrence of LOHC, it is necessary to be vigilant that it develops into severe LOHC. Early prevention and treatment of LOHC are essential. Regular monitoring of CMV-DNA and albumin levels, highly effective antiviral and antifungal therapies, and prevention of aGVHD are effective measures to prevent the occurrence and development of LOHC.

Primary cutaneous anaplastic large cell lymphoma with over-expressed Ki-67 transitioning into systemic anaplastic large cell lymphoma: A case report.

BACKGROUND: Primary cutaneous anaplastic large cell lymphoma (PC-ALCL) differs from systemic anaplastic large cell lymphoma (sALCL) in cell biological behavior, clinical features, treatment, and outcome. PC-ALCL has been reported to rarely transition into sALCL, but the underlying mechanism is not clear. Here we report such a case with certain characteristics that shed light on this. CASE SUMMARY: Herein, we report a 43-year-old male with symptoms of a skin nodule and histologically confirmed PC-ALCL with high expression of Ki-67. After three months of observation, two skin nodules re-appeared with muscle layer involvement and was histologically confirmed as sALCL. Seventeen months after receiving six cycles of CHOP regimen, the patient had pain in the chest and back, cough, shortness of breath, and night sweats. This was confirmed as relapse of sALCL by immunohistochemistry and several organs, such as the lung were involved as shown by positron emission tomography/computed tomography. After four cycles of DICE plus chidamide regimens followed by auto-hematopoietic stem cell transplantation (ASCT), complete remission (CR) duration was achieved for twelve months while the patient was on maintenance with chidamide (20 mg) pills. CONCLUSION: This case had significantly high expression of Ki-67 when diagnosed as PC-ALCL initially and then transitioned into sALCL, which is rare. Auto-ASCT combined with demethylation drugs effectively maintained CR and prolonged progression free survival.

[Clinical Analysis of Matched Sibling Donor Allogeneic Hematopoietic Stem Cell Transplantation in the Treatment of Young Patients with Multiple Myeloma].

OBJECTIVE: To investigate the efficacy and safety of matched sibling donor allogeneic hematopoietic stem cell transplantation (allo-HSCT) in the treatment of young patients with multiple myeloma (MM). METHODS: The clinical data of 8 young patients (median age：46 years) with MM who underwent allo-HSCT from HLA-indentical sibling donors in the First Affiliated Hospital of Chongqing Medical University from June 2013 to September 2021 were collected, and their survival and prognosis were retrospectively analyzed. RESULTS: All the patients were successfully transplanted, and 7 patients could be evaluated the efficacy after transplantation. The median follow-up time was 35.2 (2.5-84.70) months. The complete response (CR) rate was 2/8 before transplantation and 6/7 after transplantation. Acute GVHD developed in 2 cases and extensive chronic GVHD developed in 1 case. Within 100 days, 1 case died of non-recurrent events, and 1-year and 2-year disease-free survival were 6 and 5 cases, respectively. At the end of follow-up, all the 5 patients who survived for more than 2 years survived, and the longest disease-free survival time has reached 84 months. CONCLUSION: With the development of new drugs, HLA-matched sibling donor allo-HSCT may be a curable treatment for young patients with MM.

[Clinical Study of Cytomegalovirus Infection after Allogeneic Hematopoietic Stem Cell Transplantation].

OBJECTIVE: To explore the risk factors of cytomegalovirus (CMV) and refractory CMV infection (RCI) after allogeneic hematopoietic stem cell transplantation (allo-HSCT) and their influences on survival. METHODS: A total of 246 patients who received allo-HSCT from 2015 to 2020 were divided into CMV group (n=67) and non-CMV group (n=179) according to whether they had CMV infection. Patients with CMV infection were further divided into RCI group (n=18) and non-RCI group (n=49) according to whether they had RCI. The risk factors of CMV infection and RCI were analyzed, and the diagnostic significance of Logistics regression model was verified by ROC curve. The differences of overall survival (OS) and progression-free survival (PFS) between groups and the risk factors affecting OS were analyzed. RESULTS: For patients with CMV infection, the median time of the first CMV infection was 48(7-183) days after allo-HSCT, and the median duration was 21 (7-158) days. Older age, EB viremia and gradeⅡ-Ⅳacute graft-versus-host disease (aGVHD) significantly increased the risk of CMV infection (P=0.032, <0.001 and 0.037, respectively). Risk factors for RCI were EB viremia and the peak value of CMV-DNA at diagnosis≥1×104 copies/ml (P=0.039 and 0.006, respectively). White blood cell (WBC)≥4×109/L at 14 days after transplantation was a protective factor for CMV infection and RCI (P=0.013 and 0.014, respectively). The OS rate in CMV group was significantly lower than that in non-CMV group (P=0.033), and also significantly lower in RCI group than that in non-RCI group (P=0.043). Hematopoietic reconstruction was a favorable factor for OS (P<0.001), whereas CMV-DNA≥1.0×104 copies/ml within 60 days after transplantation was a risk factor for OS (P=0.005). CONCLUSION: The late recovery of WBC and the combination of EB viremia after transplantation are common risk factors for CMV infection and RCI. CMV-DNA load of 1×104 copies/ml is an important threshold, higher than which is associated with higher RCI and lower OS risk.

HBsAg (-)/HBsAb (-)/HBeAg (-)/HBeAb (+)/HBcAb (+) predicts a high risk of hepatitis B reactivation in patients with B-cell lymphoma receiving rituximab based immunochemotherapy.

Patterns of hepatitis B virus reactivation (HBV-R) in HBsAg (-)/HBcAb (+) patients with B-cell non-Hodgkin lymphoma (NHL) receiving rituximab based immunochemotherapy have not been well described. The retrospective study included 222 HBsAg (-)/HBcAb (+) NHL patients as training cohort and 127 cases as validation cohort. The incidence of HBV-R in HBsAg (-)/HBcAb (+) B-cell NHL patients was 6.3% (14/222), of which that in HBsAg (-)/HBsAb (-)/HBeAg (-)/HBeAb (+)/HBcAb (+) population was 23.7% (9/38). Multivariate analysis showed that HBsAg (-)/HBsAb (-)/HBeAg (-)/HBeAb (+)/HBcAb (+) correlated with a high risk of HBV-R in B-cell lymphoma patients (training phase hazard ratio [HR], 10.123; 95% confidence interval [CI], 3.389-30.239; p < 0.001; validation phase HR, 18.619; 95% CI, 1.684-205.906; p = 0.017; combined HR, 12.264; 95% CI, 4.529-33.207; p < 0.001). In the training cohort, the mortality rate of HBsAg (-)/HBcAb (+) B-cell NHL caused by HBV-R was 14.3% (2/14) while that for HBV reactivated HBsAg (-)/HBsAb (-)/HBeAg (-)/HBeAb (+)/HBcAb (+) population was up to 44.4% (4/9). As a high incidence of HBV-R and high mortality after HBV-R was found in HBsAg (-)/HBsAb (-)/HBcAb (+)/HBeAg (-)/HBeAb (+) patients with B-cell NHL receiving rituximab based immunochemotherapy, prophylactic antiviral therapy is recommended for these patients.

Comparison of CEAC, BEAM and IEAC conditioning regimens followed by autologous stem cell transplantation in peripheral T-cell lymphoma patients.

Autologous stem cell transplantation (ASCT) is an important treatment for peripheral T-cell lymphoma (PTCL) patients both during front and salvage therapy. In order to explore the appropriate conditioning regiments and seek ways to improve the efficacy and safety of PTCL, we retrospectively compared the outcomes of 52 PTCL patients treated with CEAC (lomustine, etoposide, cytarabine and cyclophosphamide; n = 28), BEAM (carmustine, etoposide, cytarabine and melphalan; n = 14) and IEAC (idarubicin, etoposide, cytarabine and cyclophosphamide; n = 10) regimens followed by ASCT at our center between 2012 and 2021. Although the time of neutrophil engraftment in CEAC group was earlier than that in IEAC group (P = 0.042) and platelet infusion in BEAM group was significantly more than CEAC group (P = 0.042), there were no significant difference in platelet engraftment, hematopoietic engraftment and red blood cells infusion among the 3 groups. The transplantation related mortality rate (TRM) and the early overall response rate (ORR) was 3.8% and 85.7% respectively. The 5-year OS and PFS was 62.8% (95% CI: 54.8-70.8%) and 61.0% (95% CI: 53.1-68.9%) respectively. There was no significant difference in TRM, ORR and survival among the 3 groups. Univariate and multivariate analysis showed that high PIT score (the T cell lymphoma prognostic index, > 1) and failure to reach complete response (non-CR) at 3 months after ASCT were common risk factors for OS (P = 0.036 and 0.007) and PFS (P = 0.021 and 0.012). In conclusion, CEAC and IEAC regimen can be used as alternative conditioning regiments for ASCT in PTCL patients, and their efficacy and safety are comparable to BEAM regiment. Patients with high PIT score and non-CR early after ASCT had worse outcomes.

[Clinical Study of Haploid Allogeneic Hematopoietic Stem Cell Transplantation Combined with Post-transplant Cyclophosphamide in Severe Aplastic Anemia Patients].

OBJECTIVE: To evaluate the clinical effect of haploid allogeneic hematopoietic stem cell transplantation(haplo-HSCT) in the treatment of severe aplastic anemia (SAA), and to explore the efficacy different between post-transplant cyclophosphamide (PT/Cy) and standard-dose ATG. METHODS: The clinical data of 38 patients with SAA in our hospital from January 2012 to December 2019 were collected and retrospectively analyzed. The efficacy was evaluated. The patients with haplo-HSCT were divided into low-dose ATG combined with PT/Cy group and standard-dose ATG group, and the blood cell hematopoietic reconstruction time, GVHD incidence, mortality and survival time of the patients in the two groups was compared. RESULTS: Among the 32 patients, hematopoietic reconstitution were detected in 9375%(30/32) recipients. The median time of neutrophil and platelet engraftment was 15(10-22) days and 13(7-30) days, respectively. The incidence of GVHD was 21.89%, the incidence of infection was 93.75%, and the 2-year overall survival rate was 84.38%. The hematopoietic reconstitution time, incidence of GVHD, mortality rate and survival time were no statistical differences between the patients in the two groups(all P>0.05). CONCLUSION: Haplo-HSCT is an effective method for the treatment of SAA，low-dose ATG combined with PT/Cy can lighten the economic burden on patients, it would be a feasible treatment plan for SAA with light side effect.

Illness uncertainty, self-perceived burden and quality of life in patients with chronic myeloid leukaemia: A cross-sectional study.

AIMS AND OBJECTIVES: To investigate the relationship between illness uncertainty, self-perceived burden and quality of life and explore the mediating role of self-perceived burden between illness uncertainty and quality of life in patients with chronic myeloid leukaemia. BACKGROUND: Patients with chronic myeloid leukaemia need long-term, potentially lifelong therapy to control the disease, which affects their quality of life. There is a need for exploring potentially changeable factors to develop interventions. Little is known about the effects of illness uncertainty and self-perceived burden on quality of life in this population. DESIGN: A cross-sectional study. METHODS: A convenience sample of 248 patients with chronic myeloid leukaemia was recruited from four university hospitals from February to August 2020. Participants were assessed with the Mishel Uncertainty in Illness Scale, Self-Perceived Burden Scale, and European Organization for Research and Treatment of Cancer Quality of Life Questionnaire. The STROBE checklist was used to report the results. RESULTS: Illness uncertainty and self-perceived burden were negatively associated with quality of life in patients with chronic myeloid leukaemia. Self-perceived burden partially mediated the relationship between illness uncertainty and quality of life. The indirect effect was -0.101, accounting for 22.9% of the total effect. CONCLUSION: The findings revealed the relationship between illness uncertainty, self-perceived burden and quality of life in patients with chronic myeloid leukaemia. Self-perceived burden exerted a mediating role between illness uncertainty and quality of life in this population. RELEVANCE TO CLINICAL PRACTICE: This study alerts healthcare providers to pay attention to patients' illness uncertainty and self-perceived burden, which can contribute to develop effective interventions to improve the quality of life among patients with chronic myeloid leukaemia in the clinical practice.

[Clinical Significance of Minimal Residual Disease Monitoring by Multi-parameter Flow Cytometry before Allogeneic Hematopoietic Stem Cell Transplantation for Prognosis of Acute Leukemia Patients].

OBJECTIVE: To investigate the clinical significance of minimal residual disease (MRD) monitoring by multiparameter flow cytometry (MFC) before allogeneic hematopoietic stem cell transplantation (allo-HSCT) in acute leukemia. METHODS: 81 cases of patients with AL treated with allo-HSCT in Department of Hematology, the First Affiliated Hospital of Chongqing Medical University form July 2015 to July 2018 was selected and retorspectively analyed. of which 79 patients were in CR and two patients were in non-CR. The CR group was further divided into two groups of MRD+ and MRD- based on the MRD level prior to HSCT. RESULTS: Among 81 patients, there were statistically significant differences in the three-year overall survival(OS) (CR 82.2%: NCR 0%), cumulative relapse incidence(RI) (CR 17.7%; NCR 100%) and leukemia-free survival rate(LFS) (CR 42.3%: NCR 0%) between CR and NCR group(P<0.05). Among 79 CR patients, MRD was negative in 30 patients while positive in 49 patients, there was significant differences in the three-year overall survival between MRD- and MRD+ group. The results of univariate analysis showed that the MRD+ group showed lower LFS compared with that of MRD- group （10.5% vs 36.2%）(P＜0.001，95%CI). CONCLUSION: MRD- patients shows longer LFS as compared with that of MRD+ patients, therefore, MRD monitoring by MFC before allo-HSCT is very important for the prognosis of the AL patients.

Identification of p90 Ribosomal S6 Kinase 2 as a Novel Host Protein in HBx Augmenting HBV Replication by iTRAQ-Based Quantitative Comparative Proteomics.

PURPOSE: The aim of this study was to screen for novel host proteins that play a role in HBx augmenting Hepatitis B virus (HBV) replication. EXPERIMENTAL DESIGN: Three HepG2 cell lines stably harboring different functional domains of HBx (HBx, HBx-Cm6, and HBx-Cm16) were cultured. ITRAQ technology integrated with LC-MS/MS analysis was applied to identify the proteome differences among these three cell lines. RESULTS: In brief, a total of 70 different proteins were identified among HepG2-HBx, HepG2-HBx-Cm6, and HepG2-HBx-Cm16 by double repetition. Several differentially expressed proteins, including p90 ribosomal S6 kinase 2 (RSK2), were further validated. RSK2 was expressed at higher levels in HepG2-HBx and HepG2-HBx-Cm6 compared with HepG2-HBx-Cm16. Furthermore, levels of HBV replication intermediates were decreased after silencing RSK2 in HepG2.2.15. An HBx-minus HBV mutant genome led to decreased levels of HBV replication intermediates and these decreases were restored to levels similar to wild-type HBV by transient ectopic expression of HBx. After silencing RSK2 expression, the levels of HBV replication intermediates synthesized from the HBx-minus HBV mutant genome were not restored to levels that were observed with wild-type HBV by transient HBx expression. CONCLUSION AND CLINICAL RELEVANCE: Based on iTRAQ quantitative comparative proteomics, RSK2 was identified as a novel host protein that plays a role in HBx augmenting HBV replication.

Mutations in basal core promoter is associated with significant fibrosis in both HBeAg positive and negative treatment-naïve chronic hepatitis B.

AIM: Assessment of liver fibrosis is important for the decision of whether to administrate antiviral treatment in chronic Hepatitis B (CHB) patients. The objective was to investigate the relationship between clinical factors and fibrosis, identify predictors of significant fibrosis in Chinese CHB patients. METHODS: Two hundred and seventy-four treatment-naïve CHB patients (208 HBeAg-positive and 66 HBeAg-negative) who performed transient elastography were consecutively included. We assessed ALT, HBsAg, HBeAg, HBV-DNA, HBV genotype and precore (PC)/basal core promoter (BCP) variants and liver stiffness measurement (LSM) values. RESULTS: One hundred and nine patients (39.78%) had significant fibrosis (F≥2, include those with liver cirrhosis). On univariate analysis, significant fibrosis was associated with older age (P<0.001), high ALT levels (P=0.003), lower HBsAg levels (P<0.001), lower HBV DNA levels (P<0.001), HBeAg negative (P<0.001), presence of BCP (P<0.001) and combined BCP/PC mutations (P=0.001). Multivariate logistic regression analysis showed that the strongest independently associated predictors of significant fibrosis (F≥2) were the presence of HBV BCP mutations (P<0.001) and older age (P<0.001), followed by presence of lower HBsAg (P<0.001), higher ALT levels (P=0.006), PC mutations (P=0.011). The diagnostic accuracy of the combination (age, ALT, HBsAg, BCP/PC variants) model with an area under the receiver-operating characteristic curve of 0.819 (cut-off value was 0.349, P<0.001, 95% CI 0.731-0.914) in predicting significant fibrosis. CONCLUSIONS: We identified four independent risk factors (age, ALT, HBsAg, HBV BCP/PC variants) in predicting significant fibrosis. HBV BCP variants was the strongest predictor of significant fibrosis. The combination of these four variables may facilitate the assessment and management of fibrosis in HBV infected patients.

Acute basophilic leukemia presenting with maculopapular rashes and a gastric ulcer: A case report.

Acute basophilic leukemia (ABL) is a rare and poorly characterized form of leukemia. The case of a 65-year-old male who complained of dizziness, maculopapular skin lesions and melena is described in the current report. A gastroscopy was conducted and indicated a gastric antral ulcer. The diagnosis of ABL was determined due to characteristic cytomorphological features, the myeloid immunophenotype of the blast cells (identified to be positive for cluster of differentiation [CD]25 and CD123) in addition to the absence of the Philadelphia chromosome and a c-kit D816V mutation. The patient initially demonstrated clinical improvement as a result of chemotherapy, however, subsequently deteriorated. The gastric and skin manifestations of ABL may be associated with excessive histamine release from basophilic cells. Thus, the administration of H1- and H2-receptor antagonists, proton pump inhibitors and steroids is proposed in order to minimize these associated complications.

[Multivariate analysis of the efficacy of laparoscopic splenectomy in the treatment of immune thrombocytopenic purpura].

OBJECTIVE: To identify factors that can effectively predict the efficacy of laparoscopic splenectomy (LS) in the treatment of immune thrombocytopenic purpura (ITP). METHODS: From January 2007 to September 2012, 78 patients with ITP underwent laparoscopic splenectomy were retrospectively analyzed. According to the postoperative platelet (PLT) count and haemorrhagic manifestations, they were divided into effective group and ineffective group. Nine influencing factors were univariate analyzed and multivariate analyzed. RESULTS: In effective group (65 cases) and ineffective group (13 cases), average PLT count of 1 day before surgery was 47×10(9)/L vs. 21×10(9)/L, average operative time was (166 ± 46) minutes vs. (139 ± 29) minutes. Univariate analysis result: PLT count of 1 day before surgery (Z = -2.776, P = 0.005) and operative time (t = 2.723, P = 0.011) was statistically significant in 2 groups, the rest factors did not significantly influence the result. Multivariate analysis revealed that only PLT count of 1 day before surgery was statistically significant (OR = 0.964, 95%CI: 0.932-0.997, P = 0.031) in 2 groups, but operative time (P = 0.051) was not statistically significant. CONCLUSIONS: PLT count of 1 day before surgery is a predict factor in LS for ITP. Because of the limited sample number, further multi-center prospective study with large sample is warrant.

A rare cause of goiter: Langerhans cell histiocytosis of the thyroid.

Goiter is a very common clinical problem; however, Langerhans cell histiocytosis (LCH) with thyroid involvement that presents as a goiter is very rare. In this article, we report one case of thyroid LCH. An 18-year-old male patient presented with goiter, polyuria, polydipsia, and lymphadenectasis of the neck, and LCH was confirmed by a lymph node biopsy and pathological investigation. Without a thyroidectomy, the goiter shrank after nine cycles of chemotherapy. In addition, we summarize the reported thyroid LCH cases in the literature from the last 10 years. LCH usually involves other organs, such as the lungs, bones, skin, pituitary gland, and lymph nodes. Thyroid LCH is more common in adults than in children, and it may coexist with a thyroid carcinoma. Without any unique thyroid manifestations, either clinically or by imaging, it is difficult to distinguish thyroid LCH from other thyroid diseases. Pathology is the gold standard for the diagnosis of LCH. A fine needle aspiration biopsy (FNAB) may help to diagnosis LCH, although sometimes it leads to misdiagnosis. Chemotherapy is recommended for multi-system LCH. Younger patients with widespread disease or who are non-responsive to chemotherapy have poor outcomes.

[Role of amifostine against the effect of etoposide on non-Hodgkin lymphoma bone marrow derived mesenchymal stem cells: an in vitro experiment].

OBJECTIVE: To study the protective role of amifostine (WR-2721) in the mesenchymal stem cells (MSC) derived from non-Hodgkin lymphoma (NHL) bone marrow treated with etoposide (VP-16). METHODS: MSC were obtained from non-Hodgkin lymphoma bone marrow, cultured in expanded medium, and then divided into 4 groups: Group A, without treatment by either WR-2721 or VP-16 and used as control group, Group B, treated with WR-2721, Group C, treated with WR-2721 + VP-16, and Group D, treated with VP-16 alone. Inverted microscopy was used to observe the growth of the MSC. Flow cytometry was used to observe the apoptosis and immunophenotypes of the MSC. Mononuclear growth and apoptosis of the MSC Mononuclear bone marrow cells were obtained from 5 healthy volunteers and added into the MSC of the 4 groups, 4 weeks later methylcellulose progenitor assay and then inverted microscopy were used to measure the numbers of colony so as to detect the hematopoiesis. MSC of different groups were put into osteocyte-inducing and adipocyte-inducing media respectively, and 2 weeks later Von Kossa staining and oil-red O staining were used to identify the differentiation into bone and fat. RESULTS: The NHL derived MSC of the 4 groups all showed a typical fibroblast-like morphology and were all positive in CD29, CD44, and CD105, while negative in CD11b, CD31, CD34, CD45, and HLA-DR. The apoptotic rate of Group D was 31.2% +/- 4.3%, significantly higher than those of the other 3 groups (all P < 0.05), and the apoptotic rate of Group C was significantly higher than those of Groups A and B (both P < 0.05), however, still significantly lower than that of Group D (P < 0.05). The ability to support hematopoiesis of Group B was not significantly different from that of Group A, and Groups C and D showed a lower ability to support hematopoiesis in comparison with Groups A and B, However, the ability of Group C was still significantly higher than that of Group D (P < 0.05). Under suitable conditions, all the MSC differentiated into osteocytes or adipocytes. CONCLUSION: Amifostine alone has no effects on proliferation, apoptosis, immunophenotype or ability of hematopoiesis support of the MSC in vitro; however, it can protect NHL patient-derived MSC from injury by VP-16 in vitro.

[Indoleamine 2, 3-dioxygenase activity in acute myeloid leukemia cells contributing to tumor immune escape].

This study was aimed to investigate the mechanism of indoleamine 2, 3-dioxygenase (IDO) activity in acute myeloid leukemia cells contributing to tumor immune escape. Myeloid leukemia cells were isolated from bone marrow of 23 patients with acute myeloid leukemia (AML) and IDO expression was detected by immunochemistry and RT-PCR methods. Then mixed lymphocyte reaction (MLR) of one way was carried out, leukemia cells were used as stimulating cells and T-lymphocytes were used as reactive cells in culture with or without 1-MT. T-lymphocyte proliferation rate was determined by MTT assay and IDO activity in supernatant of MLR was detected by high-performance liquid chromatography (HPLC). The results showed that IDO expression was found in 17 out of 23 cases of acute myeloid leukemia cells; IDO enzyme activity in leukemia cells inhibited T-lymphocyte proliferation in MLR cultures. It is concluded that IDO activity expressing in leukemia cells can suppress T-lymphocyte proliferation responses, which may be contributing to tumor immune escape.

[Biological characteristics and ability of supporting hematopoiesis of bone marrow mesenchymal stem cells pre- and post-cryop-reservation].

This study was aimed to observe the biological characteristics of cryopreserved bone marrow mesenchymal stem cell (MSC) and to examine their abilities to support in vitro hematopoiesis. Bone marrow MSC were cryopreserved in -196 degrees C liquid nitrogen for 4 weeks (short term) and 9-15 months (medium term) with IMDM containing 10% DMSO, 40% fetal calf serum as cryoprotectant. The viability, proliferation, immunophenotype, in vitro differentiation and ability of supporting hematopoiesis of thawed MSC were investigated and compared with these of pre-cryopreserved MSC. The results showed that the cell viability were (93 +/- 2.51)% and (90 +/- 3.75)% for MSC cryopreserved as long as 4 weeks or 9-15 months respectively. However, there were no changes detected, as compared with pre-cryopreserved MSC in immunophenotype, abilities of proliferation and supporting colony forming of CFU-GM, CFU-E and CFU-GEMM. It is concluded that bone marrow-derived MSC can be stored in liquid nitrogen for short-term (4 weeks) or medium-term (9-15 months) without changes of abilities of proliferation, differentiation and hematopoiesis support.

[Mechanism of G2/M blockage triggered by activated-Chk1 in regulation of drug-resistance in K562/A02 cell line].

The study was purposed to investigate the effect of phosphorylated-chk1 on cell cycle and apoptosis of human erythroleukemic cell line K562 and K562/A02, and to explore the mechanism of chk1 in regulation of drug-resistance of leukemia cells. After treatment with adrimycin for six hours, the cell cycle distribution was detected by flow cytometry; the Chk1mRNA expression was detected by RT-PCR and the Chk1 phosphorylation level was detected by Western blot. Under the condition of down-regulation of Chk1mRNA expression in cells transfected with Chk1 short hairpin RNA, the cell apoptosis rates were detected by flow-cytometry following adrimycin. The results indicated that the proportion of K562/A02 cell line in G2/M phase was (54.12 +/- 0.57)% at 6 hours after drug treatment, significantly higher than that of K562 cell line (36.99 +/- 1.28)%. No evident difference of the Chk1mRNA expression was observed between K562 and K562/A02 cell lines, while elevated Chk1 phosphorylation following DNA damage induced by adriamycin was observed in the K562/A02 cell line (0.79 +/- 0.56), significantly higher than that in K562 cell line (0.27 +/- 1.47). The cell apoptosis rate of the Chk1 shRNA group in K562/A02 cell line was 3.84-fold of blank vector group, but that in K562 cell line was 1.30-fold of blank vector group. It is concluded that the increased chk1 activity that delay the progress of cell cycle are associated with cellular resistance to adrimycin in the K562/A02 cell line.

[Isolation and identification of chronic myelogenous leukemia bone marrow mesenchymal stem cells and their functional characteristics].

OBJECTIVE: To isolate and culture bone marrow mesenchymal stem cells (MSCs) from chronic myelogenous leukemia (CML) patients and examine their functional characteristics. METHODS: Bone marrow was extracted from the anterior superior iliac spines of 21 patients with CML. MSCs were isolated and cultured. Single colony derived MSCs were harvested by limiting dilution. The cell cycle and immunophenotype of the expanded clonal MSCs were detected by fluorescence-activated cell sorter (FACS). Different agents were used to induce the MSCs to differentiate into osteocyte, adipocyte and neural cells. Von Kossa staining, oil-red staining, and Western blotting was used to examine the ability of differentiation. PCR was used to detect the expression of BCR/ABL gene. The ultrastructure of the CML derived MSCs was observed with electron microscopy. Sixteen BALB/c nude mice were randomly divided into 2 equal groups to be inoculated with HL60 cancer cells and CML derived MSCs to observe the tumorigenicity. MSCs were cultured in soft agar for 2 weeks to observe the clone growth. RESULTS: Fibroblast-like, positive in CD29, CD44, and CD105, and negative in CD116, CD34, CD48, and HLA-DR, the CML derived MSCs could differentiate into osteocyte, adipocyte and neural cells. CML derived MSCs showed normal karyotype and ultrastructure, they did not express BCR/ABL gene. After 2 weeks' culture no clone was formed from the MSCs. Four weeks after tumors were shown in 6 of the 8 mice inoculated with HL60 cells, and no tumor was seen in the mice inoculated with MSCs. CONCLUSION: Able to differentiate into different types of cell and without tumorigenicity, MSCs from the bone marrow of CML patients have the potentiality in clinical application.