Efficacy and safety of high-dose intramuscular vitamin D2 injection in type 2 diabetes mellitus with distal symmetric polyneuropathy combined with vitamin D insufficiency: study protocol for a multicenter, randomized, double-blinded, and placebo-controlled trial.

Background: Distal symmetric polyneuropathy (DSPN) is the most common chronic complication of type 2 diabetes mellitus (T2DM). DSPN may lead to more serious complications, such as diabetic foot ulcer, amputation, and reduced life expectancy. Observational studies have suggested that vitamin D deficiency may be associated with the development of DSPN in T2DM. However, interventional studies have found that low-dose vitamin D supplementation does not significantly improve neuropathy in DSPN. This study aims to evaluate the efficacy and safety of intramuscular injection of high-dose vitamin D (HDVD) in T2DM with DSPN combined with vitamin D insufficiency. Methods and analysis: We will conduct a multicenter, randomized, double-blinded, and placebo-controlled trial in four large hospitals. All eligible participants will be randomly assigned to either the vitamin D2 supplement or placebo control group and injected intramuscularly monthly for 3 months. Additionally, anthropometric measurements and clinical data will be collected at baseline and 3 months. Adverse events will be collected at 1, 2, and 3 months. The primary outcome measure is the change in the mean Michigan Neuropathy Screening Instrument (MNSI) score at baseline and 3 months post-intervention. We will use the gold-standard liquid chromatography-tandem mass spectrometry method to distinguish between 25(OH)D2 and 25(OH)D3 levels. The MNSN score before the intervention will be used as a covariate to compare the changes between both groups before and after the intervention, and the analysis of covariance will be used to analyze the change in the MNSI score after HDVD supplementation. Discussion: Glycemic control alone does not prevent the progression of DSPN in T2DM. Some studies have suggested that vitamin D may improve DSPN; however, the exact dose, method, and duration of vitamin D supplementation are unknown. Additionally, neuropathy repair requires HDVD supplementation to sustain adequate vitamin D levels. This once-a-month intramuscular method avoids daily medication; therefore, compliance is high. This study will be the first randomized controlled trial in China to analyze the efficacy and safety of HDVD supplementation for patients with T2DM and DSPN and will provide new ideas for pharmacological research and clinical treatment of diabetic neuropathy. Clinical trial registration: https://www.chictr.org.cn/, identifier ChiCTR2200062266.

Case report: Plasma cell leukemia secondary to multiple myeloma successfully treated with anti-BCMA CAR-T cell therapy.

Chimeric antigen receptor (CAR)-T cell therapy provides an effective salvage treatment for relapsed/refractory multiple myeloma (RRMM) patients. End-stage RRMM with plasma cell leukemia (PCL) transformation is highly aggressive and resistant to conventional therapy. There is an urgent need for new therapeutics and CAR-T therapy may play an important role. We report a case of PCL secondary to RRMM successfully treated with CAR-T cell therapy targeting B-cell maturation antigen (BCMA). A woman was diagnosed as having MM 4 years ago and progressed to secondary PCL (sPCL) of five prior lines of treatment including proteasome inhibitors, an immunomodulatory agent, cytotoxic drugs, and an anti-CD38 monoclonal antibody. After receiving a BCMA CAR-T therapy, she achieved a stringent complete response that lasted 9 months. Then, the patient irregularly took venetoclax 10 mg per day due to a slightly higher λ FLC concentration, which did not meet the criteria for progression. She maintained a complete response for the following 7 months. In conclusion, BCMA CAR-T therapy may be a promising therapeutic approach in PCL patients. More studies are needed to evaluate the benefit of anti-BCMA CAR-T therapy in PCL patients. Clinical Trial Registration: www.chictr.org.cn, ChiCTR1900024388, Registered 9 July 2019.

The value of ultrasound-guided fine needle aspiration in the diagnosis of diffuse large B-cell lymphoma: A single center experiment.

OBJECTIVES: Flow cytometry (FC) is a critical diagnostic approach for guiding targeted chemotherapy and cellular immunotherapy for relapsed and refractory lymphoma patients. The aim of the study was to investigate the value of ultrasound-guided fine needle aspiration (FNA) to improve the quality of FC specimens in relapsed and refractory diffuse large B-cell lymphoma (R/R DLBCL). METHODS: Twenty patients with R/R DLBCL after standard treatment were included. The primary lesions of all cases were confirmed by pathology. FNA and core needle biopsy (CNB) were both used for ultrasound-guided puncture, the specimens obtained by FNA are directly examined by FC, and the specimens by CNB were subjected to FC after grinding. The accuracy of FC with the two methods were evaluated using histopathology as the gold standard. RESULTS: Of the 20 R/R DLBCL cases, 19 were diagnosed as DLBCL pathologically and one was diagnosed as inflammatory granuloma. Among the specimens obtained by CNB, 14 cases examined by FC after grinding showed abnormal mature B cells, five cases were missed, all cases are not misdiagnosed. Among the specimens obtained by FNA, 18 cases showed FC-confirmed abnormal mature B cells, one case was missed, all cases are not misdiagnosed. The sensitivity, specificity, and accuracy of FC with CNB and FNA were 73.68 % (14/19) vs 94.73 % (18/19), 100 % (1/1) vs 100 % (1/1), and 75 % (15/20) vs 97.14 % (19/20), respectively. The sensitivity of the two puncture methods of FC of DLBCL was statistically different (p < 0.001). CONCLUSION: Sampling with ultrasound-guided FNA is of great value to improve the quality of FC specimens. FNA can significantly improve the sensitivity and accuracy of FC diagnosis in R/R DLBCL.

CAR-T therapy as a consolidation in remission B-ALL patients with poor prognosis.

BACKGROUND: To date, almost all studies regarding chimeric antigen receptor (CAR)-T cell therapy for B-cell acute lymphoblastic leukemia (B-ALL) were performed in refractory/relapsed (r/r) or minimal residual disease-positive patients. CAR-T therapy in remission patients has not been reported. AIM: To observe the treatment outcome of CAR-T cells for remission B-ALL patients with poor prognosis. METHODS AND RESULTS: CAR-T treatment was applied to two B-ALL patients in remission status who had poor prognostic factors and refused transplantation, and one case was unable to accept standard chemotherapy owing to multiple complications. The procedure of CAR-T therapy in these two remission patients was the same as that in r/r B-ALL patients. Lentiviral vectors encoding second generation CARs composed of CD3ζ and 4-1BB were used to produce CAR-T cells. Lymphodepleting agents fludarabine and cyclophosphamide were administered prior to cell infusion. Grade I cytokine release syndrome occurred after each T-cell infusion and there was no neurotoxicity. CAR-T treatment followed by non-intensive maintenance chemotherapy and targeted drugs allowed both patients to obtain a long-term event-free survival of more than three and a half years without transplantation. CONCLUSIONS: CAR-T therapy could be used in high-risk B-ALL patients as a consolidation to avoid transplantation, the combination of CAR-T and following maintenance therapy may be better than CAR-T alone for durable remission.

Humanized CD19 CAR-T cells in relapsed/refractory B-ALL patients who relapsed after or failed murine CD19 CAR-T therapy.

BACKGROUND: For CD19-positive relapsed/refractory B-cell acute lymphoblastic leukemia (r/r B-ALL) after treatment with murine CD19 (mCD19) CAR-T, the reinfusion of mCD19 CAR-T cells may be ineffective due to anti-mouse single-chain variable fragment (scFv) antibody caused by mCD19 CAR. To overcome this immunogenicity, we applied humanized CD19 (hCD19) CAR-T cells to treat r/r B-ALL patients with prior mCD19 CAR-T therapy. METHODS: Nineteen pediatric and adult patients were included, 16 relapsed after and 3 were primarily resistant to mCD19 CAR-T. All patients presented with more than 5% blasts in bone marrow and/or extramedullary disease, and still showed CD19 antigen expression. Humanized CD19-CARs were lentiviral vectors carrying a second generation CAR with 4-1-BB co-stimulatory and CD3ζ signaling domains. Patient-derived cells were collected for producing CAR-T cells, the median dose of infused hCD19 CAR-T cells was 2.4 × 105/kg (range, 1.0-18.0 × 105/kg). RESULTS: hCD19 CAR-T resulted in a complete remission (CR) rate of 68% (13/19). Among 13 remission patients, 11 underwent allogeneic hematopoietic cell transplantation (allo-HCT) (3 were second HCT) and 10 remained in CR; the event-free survival rates at 12-18 months were 91% in 11 patients received following allo-HCT and 69% in all CR patients. Six cases had no response to hCD19 CAR-T, 3 died of disease progression; another 3 received salvage second transplantation, of them, 2 relapsed again (one died). Cytokine release syndrome (CRS) occurred in 95% (18/19) of patients, most CRS events were grade 1 and grade 2 (n = 17), there was only one grade 4 CRS. Two cases experienced grade 1 neurotoxicity. CONCLUSIONS: Humanized CD19 CAR-T cell therapy could be a treatment option for CD19-positive B-ALL patients who relapsed after or resisted prior murine CD19 CAR-T, hCD19 CAR-T followed by allo-HCT provided a longer remission in CR patients. Nevertheless, the prognosis of non-responders to hCD19 CAR-T remained dismal. TRIAL REGISTRATION: Chinese Clinical Trial Registry/WHO International Clinical Trial Registry ( ChiCTR1900024456 , URL: www.chictr.org.cn ); registered on July 12, 2019.

Peripheral leukemia burden at time of apheresis negatively affects the clinical efficacy of CART19 in refractory or relapsed B-ALL.

Our previous clinical study achieved complete remission (CR) rates of >90% following chimeric antigen receptor T cells targeting CD19 (CART19) treatment of refractory/relapsed B cell acute lymphoblastic leukemia (r/r B-ALL); however, the influence of the leukemia burden in peripheral blood (PB) blasts remains unclear. Here, we retrospectively analyzed 143 patients treated with CART19 (including 36 patients with PB blasts) to evaluate the effect of peripheral leukemia burden at the time of apheresis. One hundred seventeen patients with high disease burdens achieved 91.5% CR or incomplete count recovery CR and 86.3% minimal residual disease-negative CR, and 26 patients with low disease burdens obtained 96.2% MRD- CR. Collectively, 9 of 36 (25%) patients with PB blasts and 2 of 107 (1.87%) patients without PB blasts did not respond to CART19 therapy. The leukemia burden in PB negatively influenced ex vivo cell characteristics, including the transduction efficiency of CD3+ T cells and their fold expansion, and in vivo cell dynamics, including peak CART19 proportion and absolute count, fold expansion, and persistence duration. Further studies showed that these patients had higher programmed death-1 expression in CART19 products. Our data imply that PB blasts negatively affected CART19 production and the clinical efficacy of CART19 therapy in patients with r/r B-ALL.

Combination of CD19 and CD22 CAR-T cell therapy in relapsed B-cell acute lymphoblastic leukemia after allogeneic transplantation.

The prognosis of relapsed acute lymphoblastic leukemia (ALL) after allogeneic transplantation is dismal when treated with conventional approaches. While single-target CD19 or CD22 chimeric antigen receptor (CAR) T-cell therapy has achieved high complete remission (CR) rates in refractory/relapsed B-ALL, it could not maintain a durable remission in most patients. To prolong relapse-free survival, we sequentially combined CD19 and CD22 CAR-T cells to treat post-transplant relapsed B-ALL patients with both CD19/CD22 antigen expression on lymphoblasts. Patient-derived donor cells were collected to produce CAR-T cells that were transfected by lentiviral vectors encoding second generation CARs composed of CD3ζ and 4-1BB. The second T-cell infusion was scheduled at least 1 month, and usually within 6 months after the first CAR-T treatment. Twenty-seven adult and pediatric patients, including 11 (41%) with extramedullary diseases (EMD), received the first CD19 CAR-T and 23 (85%) achieved CR. Subsequently, 21 out of 27 patients received the second CD22 CAR-T and were followed-up for a median of 19.7 (range, 5.6-27.3) months; 14 cases remained in CR, seven relapsed and two of them died from disease progression; Kaplan-Meier survival analysis showed overall survival and event-free survival rates of 88.5% and 67.5%, respectively, at both 12 months and 18 months. CAR-T associated graft-versus-host disease (GVHD) occurred in 23% of patients, with 8% new-onset acute GVHD and 15% persistent or worsened pre-existing cGVHD before CAR-T. This combination strategy of sequential CD19 and CD22 CAR-T therapy significantly improved the long-term survival in B-ALL patients who relapsed after transplantation.

CD22 CAR T-cell therapy in refractory or relapsed B acute lymphoblastic leukemia.

Despite worldwide promising clinical outcome of CD19 CAR-T therapy, relapse after this therapy is associated with poor prognosis and has become an urgent problem to be solved. We conducted a CD22 CAR T-cell therapy in 34 relapsed or refractory (r/r) B-ALL pediatric and adult patients who failed from previous CD19 CAR T-cell therapy. Complete remission (CR) or CR with incomplete count recovery (CRi) was achieved in 24 of 30 patients (80%) that could be evaluated on day 30 after infusion, which accounted for 70.5% of all 34 enrolled patients. Most patients only experienced mild cytokine-release syndrome and neurotoxicity. Seven CR patients received no further treatment, and 3 of them remained in remission at 6, 6.6, and 14 months after infusion. Eleven CR patients were promptly bridged to transplantation, and 8 of them remained in remission at 4.6 to 13.3 months after transplantation, resulted in 1-year leukemia-free survival rate of 71.6% (95% CI, 44.2-99.0). CD22 antigen loss or mutation was not observed to be associated with relapsed patients. Our study demonstrated that our CD22 CAR T-cells was highly effective in inducing remission in r/r B-ALL patients, and also provided a precious window for subsequent transplantation to achieve durable remission.

Germline cytotoxic lymphocytes defective mutations in Chinese patients with lymphoma.

Certain patients with lymphoma may harbor mutations in perforin 1 (PRF1), unc-13 homolog D (UNC13D), syntaxin 11 (STX11), STXBP2 (syntaxin binding protein 2) or SH2 domain containing 1A (SH2D1A), which causes functional defects of cytotoxic lymphocytes. Data regarding the association between genetic defects and the development of lymphoma in Chinese patients are limited to date. In the present study, 90 patients with lymphoma were analyzed for UNC13D, PRF1, STXBP2, STX11, SH2D1A and X-linked inhibitor of apoptosis. Mutations were observed in 24 (26.67%) patients; 16 patients exhibited mutations in UNC13D, 7 exhibited PRF1 mutations, and 1 exhibited monoallelic mutation in STX11. UNC13D c.2588G>A/p.G863D mutation was detected in 9 patients (10.00%) and in 4/210 controls (1.90%). This mutation was predicted to be pathogenic and it predominantly existed in the Chinese population. These findings suggest that impaired cytotoxic machinery may represent a predisposing factor for the development of lymphoma. Furthermore, these data describe a distinct mutation spectrum in Chinese patients with lymphoma, whereby UNC13D is the most frequently mutated gene. In addition, these findings suggest UNC13D c.2588G>A mutation is a founder mutation in Chinese patients.

Genome-wide analysis of phylogeny, expression profile and sub-cellular localization of SKP1-Like genes in wild tomato.

SKP1 is a core component of SCF complex, a major type of E3 ubiquitin ligase catalyzing the last step in ubiquitin-mediated protein degradation pathway. In present study, SKP1 gene family in Solanum pimpinellifolium (SSK), a wild species of tomato, was investigated. A total of 19 SSK genes were identified through homologous search. Their chromosomal locations, gene structures, phylogeny, expression profiles, sub-cellular localizations and protein-protein interaction patterns with putative F-box proteins were analyzed in detail. The high homology and similar expression patterns among clustered SSK genes in chromosome suggested that they may have evolved from duplication events and are functionally redundant. Sub-cellular localization indicated that most of the SSK proteins are distributed in both cytosol and nucleus, except for SSK8, which is detected in cytosol only. Tissue-specific expression patterns suggested that many SSK genes may be involved in tomato fruit development. Furthermore, several SSK genes were found to be responsive to heat stress and salicylic acid treatment. Based on phylogenetic analysis, expression profiles and protein interaction property, we proposed that tomato SSK1 and SSK2 might have similar function to ASK1 and ASK2 in Arabidopsis.

[Misdiagnosis of 3 cases lymphoma due to misjudgement of immunohistochemistry].

OBJECTIVE: To recognize the importance of analyzing the result of immunohistochemical staining correctly. METHOD: Review of the three misdiagnosed cases lymphoma and exploring the causes of misdiagnosis through reviewing their clinics, histopathology and immunohistochemistry. RESULTS: Case 1 of lymphocyte rich classical Hodgkin's lymphoma (LRCHL) was misdiagnosed as follicular lymphoma (FL) initially, the RS cells were overlooked morphologically and wrongly determined BCL-2 and CD20-positive cells as tumor cells immunohistochemically; also once misdiagnosed as nodular lymphocyte predominant Hodgkin's lymphoma (NLPHL) because the CD20-negative RS misjudged cells as the positives. Case 2 of AML tumor cells expressed TdT, CD7 and CD43 unspecifically, which misdiagnosed as T-cell lymphoblastic lymphoma (T-LBL). Case 3 of type B1 thymoma was misdiagnosed as T-LBL, because CK wasn't expressed satisfactorily resulting in neglecting neoplastic epithelial cells, and lymphocytes in the background were TdT and CD99-positive. CONCLUSION: The diagnosis of lymphoma should be based on morphology, immunohistochemistry, clinics, and genetics. Moreover, the correct judgment of immunohistochemical staining is essential to make right diagnosis.

[Predictable recurrence by regular monitoring minimal residual disease with flow cytometry in the patients with both AML and ALL: a single-center study of 163 cases].

OBJECTIVE: To study the predictable value of monitoring minimal residual disease (MRD) regularly by flow cytometry (FCM) in patients with acute leukemia (AL) in the first complete remission (CR(1)). METHODS: From April 2005 to July 2009, AL patients who had got CR(1) after chemotherapy were regularly monitored for MRD in bone marrow by FCM to relapse or to July 2010 in Beijing Daopei Hospital (not including those received stem cell transplantation). The special antibody combinations were employed for each patient according to aberrant expression of leukemia cells. MRD(+) was defined as the aberrant cells more than 0.01%. The probability of continuous CR (CCR) was calculated by Kaplan-Meier formula, and the statistical difference between two CCR probabilities was evaluated by log-rank test. RESULTS: A total of 163 AL patients in CR(1) were monitored to relapse or to July 2010. Among 89 AML patients referred to our hospital within 1 year after diagnosis, 30 cases were in MRD(+) and 59 cases MRD(-) till 12 months following chemotherapy, 3/30 patients in MRD(+) and 47/59 remained in CCR to July 2010. The probability of CCR at 24, 36 months was 13%, 13%in MRD(+) group, 94%, 78% in MRD(-) group respectively, the difference between them was statistically significant (P < 0.01). Among 35 ALL referred to our hospital within 5 months after diagnosis, 13 cases were MRD(+) and 22 cases MRD(-) till 5 months following chemotherapy, 0/13 patients in MRD(+) and 20/22 patients in MRD(-) remained in CCR to July 2010. The probability of CCR at 24, 36 months was 0% in MRD(+) group, 96%, 96% in MRD(-) group respectively, the difference between them was statistically significant (P < 0.01). Over the time point above, all patients with MRD(+) or their MRD from negative to positive relapsed finally, and most patients with MRD(-) remained CCR to July 2010. CONCLUSION: It had a clinical prognostic value to monitor MRD regularly by FCM in the patients with AL after CR(1).

[The clinical and laboratory features of 9 cases with gammadeltaT cell lymphoma or leukemia].

OBJECTIVE: To analyze the clinical and laboratory features of 9 cases of gammadeltaT cell lymphoma or leukemia. METHODS: From 2007 to 2011, 9 patients with gammadeltaT-cell lymphoma/leukemia were diagnosed in our hospital. The immunophenotype of the abnormal cells were detected by flow cytometry, clonal gene rearrangement of IgH, TCRgamma, TCRdelta by PCR, chromosome karyotype analysis by G banding, acute leukemia gene and the DNA of type 1 - 8 human herpes virus by multiple nested PCR, The gammadeltaT cells were determined by T cell with TCR gammadelta chain, the malignant gammadelta T cells by the abnormal expression of T cell antigens and the precursor malignant gammadelta T cells by the expression of CD34, TDT, CD99, CD1 a or acute leukemia genes. RESULTS: In the 9 patients with gammadeltaT cell lymphoma leukemia, significant malignant gammadeltaT cells infiltration of bone marrow were found in 8 with blast morphology. 5 were diagnosed as T-ALL/LBL (gammadeltaT type) and 4 HSgammadelta TCL. The clonal gene rearrangement of TCRgamma and/or TCRB were detected in 6/6 patients. Patients either did not achieve complete remission(CR) after induction therapy or relapsed quickly after CR. Only 4/5 patients remained continuous CR(CCR) at 2, 2, 3,12 months respectively, after allogeneic hematopoietic stem cell transplantation (allo-HSCT), the fifth T-ALL (gammadeltaT) relapsed 1 month after allo-HSCT. CONCLUSIONS: The incidence of gammadelta T cell lymphoma or leukemia may be higher than reported, part of them were T-ALL/LBL with poor prognoses. FCM and clonal gene rearrangement of TCRgamma and/or TCRdelta are helpful to diagnosis. Allo-HSCT may be the only curative approach.

[Evaluation of polymorphic post-allotransplant lymphoproliferative disorder by flow cytometry.].

OBJECTIVE: To study the role of flow cytometry (FCM) in detection of polymorphic post-transplant lymphoproliferative disorders (PTLD). METHODS AND RESULTS: Two patients presented with fever and multiple lymphadenopathy on day 46 and day 50 respectively after successful allogeneic hematopoietic stem cell transplantation (allo-HSCT). The symptoms couldn't be controlled by antibiotics. The polymorphic PTLD was diagnosed based on the elevation of bone marrow EB virus DNA and detection of subsets of light chain restricted B cells and/or plasma cells in peripheral blood (PB) samples. The lymphocyte immunophenotypes from PB and/or bone marrow (BM) samples were serially tested by FCM after lowering the dose of immunosupressive agents and treating with antivirus drugs, anti-CD20 antibodies, and cytotoxic T cell infusion. B cells were undetable in two patient, but monoclonal plasma cells appeared or maintained. One patient died after two weeks. Another patient was still on treatment. B cells and plasms cells couldn't be detected in her PB, but there were monoclonal plasma cells in her BM. FCM have a prominent advantage in detect polymorphic PTLD, since it can effectively recognize different cell groups in blood and identify monoclonal subsets. Besides, the immunophenotype of plasma cells in polymorphic PTLD might be different from that in typical plasma cell myeloma. CONCLUSION: Polymorphic PTLD can be detected and followed up by FCM. BM is more suitable than PB for monitoing the disease. Besides lymph node biopsy, B cell abnormaliity could be detected in PB in allo-HSCT patients.

Natural killer/T cell lymphoma initiating with pleural effusion: the significance of MICM combined techniques for the diagnosis.

Natural killer (NK)/T-cell lymphomas represent a rare type of lymphoma derived from either activated NK cells or cytotoxic T cells. They are most commonly extranodal and tend to present as destructive lesions within the midline facial structures. Other than the nasal cavity and Para nasal sinuses, several other extra nodal sites of involvement have been reported, including the pharynx, gastrointestinal tract, and testis. Occasionally, pleural effusion has also been observed. Here, a case of lymphoma of NK/T-cell type presented as pleural effusion was reported. The patient was previously misdiagnosed as B cell non-Hodgkin's lymphoma by pathological and immunohistochemistry (IH) analysis for pleural membrane biopsy specimen. After the analysis of the pleural fluid cells by a combination of morphologic, immunophenotypic, cytogenetic and molecular (MICM) methods in Beijing Dao-Pei hospital, some lymphoblasts were found morphologically, which expressed cytoplasmic CD3 (cCD3) and CD56 by flow cytometry analysis and had a clonal T-cell receptor gamma (TCR-gamma) gene rearrangement by molecular analysis, so that the diagnosis was finally corrected as NK/T-cell lymphoma and an allogeneic stem cell transplantation was successfully performed. In conclusion, this unusual case highlights the significance of MICM combined techniques for the diagnosis of lymphoma, as well as an unusual presentation of a rare disease and the successful treatment.

[Analysis of variant translocation der ins (17; 15) in patient with APL by G-banding technique and interphase fluorescence in situ hybridization].

To investigate the biological characteristics of the variant translocation der ins (17;15) in a patient with acute promyelocytic leukemia (APL), the conventional G-banding technique, interphase fluorescence in situ hybridization (int-FISH), RT-PCR, gene scanning, gene sequence and flow cytometry were performed. The results indicated that the variant translocation der ins (17, 15) observed by G banding technique was a rare type, the int-FISH assay by using dual-color pml/raralpha fusion probes confirmed the cytogenetic findings. The detection results of other molecular methods demonstrated the existence of the whole pml/raralpha fusion gene, while this case had insertion variant translocation. This patient got complete remission by using combined chemotherapy, and survives with continuous complete remission during following up for 1 year. In conclusion, the variant translocation der ins (17; 15) is rare type in APL, its incidence is lower, several signal types in detection of int-FISH were observed and the combination chemotherapy for this patient showed more obvious efficacy.

[Phenol butyrate inhibits cell cycle of leukemia cell lines through up-regulation of p21WAF1/CIP1 gene].

OBJECTIVE: To elucidate effects of histone deacetylase inhibitors on cell cycle of leukemia cell lines and investigate its molecular mechanisms. METHODS: Kasumi-1, U937 and NB4 cell lines were exposed to a histone deacetylase inhibitor, phenyl butyrate (PB), for 24, 48 and 72 hrs. Cells were harvested for cell cycle analysis by flow cytometry. Gene expression of p21WAF1/CIP1, a cyclin-dependent kinase inhibitor, was determined by semi-quantitative reverse transcriptase polymerase chain reaction (semi-quantitative RT-PCR). Promoter activity of p21WAF1/CIP1 was determined by luciferase-reporter assay in 293T cell line. RESULTS: PB inhibited cell cycle of Kasumi-1, U937 and NB4 cell lines, showing G(0)/G(1) phase arrest and S-phase fraction reduction with a dose and time dependent manner. After Kasumi-1, U937 or NB4 cells exposed to 3 mmol/L PB for 72 hrs, G(0)/G(1)-phase fraction was increased by 42.03%, 44.36% and 26.82%, and S-phase fraction was decreased by 31.86%, 38.9% and 26.77%, respectively. After Kasumi-1, U937 and NB4 cell lines exposed to PB, the expression of p21WAF1/CIP1 gene was increased by (2.06 +/- 0.27), (2.78 +/- 0.40) and (1.78 +/- 0.20) times at its maximum, respectively. PB could stimulate p21WAF1/CIP1 promoter activity (by luciferase-reporter assay) and the effect was dose dependent. The promoter activity was increased by 5.74 times after the cells exposed to 3 mmol/L PB for 48 hrs. PB stimulating p21WAF1/CIP1 promoter activity was mainly mediated by a 101 base pairs fragment upstream of transcription start site. CONCLUSION: PB could inhibit cell cycle of leukemia cell lines. The effects were mainly through up-regulation of p21WAF1/CIP1 expression.