Basiliximab for steroid-refractory acute graft-versus-host disease: A real-world analysis.

Steroid-refractory (SR) acute graft-versus-host disease (aGVHD) is one of the leading causes of early mortality after allogeneic hematopoietic stem cell transplantation (allo-HSCT). We investigated the efficacy, safety, prognostic factors, and optimal therapeutic protocol for SR-aGVHD patients treated with basiliximab in a real-world setting. Nine hundred and forty SR-aGVHD patients were recruited from 36 hospitals in China, and 3683 doses of basiliximab were administered. Basiliximab was used as monotherapy (n = 642) or in combination with other second-line treatments (n = 298). The cumulative incidence of overall response rate (ORR) at day 28 after basiliximab treatment was 79.4% (95% confidence interval [CI] 76.5%-82.3%). The probabilities of nonrelapse mortality and overall survival at 3 years after basiliximab treatment were 26.8% (95% CI 24.0%-29.6%) and 64.3% (95% CI 61.2%-67.4%), respectively. A 1:1 propensity score matching was performed to compare the efficacy and safety between the monotherapy and combined therapy groups. Combined therapy did not increase the ORR; conversely, it increased the infection rates compared with monotherapy. The multivariate analysis showed that combined therapy, grade III-IV aGVHD, and high-risk refined Minnesota aGVHD risk score before basiliximab treatment were independently associated with the therapeutic response. Hence, we created a prognostic scoring system that could predict the risk of having a decreased likelihood of response after basiliximab treatment. Machine learning was used to develop a protocol that maximized the efficacy of basiliximab while maintaining acceptable levels of infection risk. Thus, real-world data suggest that basiliximab is safe and effective for treating SR-aGVHD.

Roxadustat Improves Erythropoietin Antibody-Mediated Pure Red Cell Aplasia in a Patient with Hemodialysis.

Anemia is a common complication of chronic kidney disease (CKD). Recombinant human erythropoietin (rHu-EPO) is used extensively in patients with CKD. However, anti-erythropoietin (anti-EPO) antibody has been reported during rHu-EPO treatment, which causes pure red cell aplasia (PRCA). We presented a case of 75-year-old man, who underwent hemodialysis for 2 years. He developed PRCA during rHu-EPO treatment. The rHu-EPO was immediately discontinued, and the patient was given roxadustat treatment. After 6 months of roxadustat treatment, the anti-EPO antibody was disappeared, and hemoglobin recovered normal range. The results suggest that roxadustat can be used to treat patients with anti-EPO antibody-mediated PRCA without immunosuppressive therapy.

Long Non-Coding RNA RP11-789C1.1 Suppresses Epithelial to Mesenchymal Transition in Gastric Cancer Through the RP11-789C1.1/MiR-5003/E-Cadherin Axis.

BACKGROUND/AIMS: Gastric cancer (GC) is a common malignancy with a global incidence that ranks fourth among all tumor types. Epithelial-to-mesenchymal transition (EMT) is a tumor biological process with a role in GC cell metastasis. Long non-coding RNAs (lncRNAs) and microRNAs possess important regulatory functions at the cellular level and in diverse pathophysiological processes. This study was conducted to investigate whether lncRNA RP11-789C1.1 regulates EMT in GC by mediating the miR-5003/E-cadherin pathway. METHODS: RP11-789C1.1 and miR-5003 expression was detected in GC specimens and cell lines by quantitative real-time PCR. Western blotting and immunohistochemistry were performed to detect EMT markers in GC. Cell Counting Kit 8 assays were carried out to explore cell proliferation. Wound healing and Transwell assays were conducted to determine the migration and invasion of GC cells. To clarify the correlation between RP11-789C1.1, miR-5003, and E-cadherin, dual-luciferase reporter assays were applied. RESULTS: LncRNA RP11-789C1.1 was significantly down-regulated in GC patients and cell lines, along with the concomitant up-regulation of miR-5003. Silencing RP11-789C1.1 and over-expressing miR-5003 significantly promoted the tumor behavior of GC cells. Dual-luciferase reporter assays confirmed that miR-5003 was the target of both RP11-789C1.1 and E-cadherin. Furthermore, at both the mRNA and protein level, silencing RP11-789C1.1 remarkably reduced the expression of E-cadherin and promoted EMT, which were reversed by knocking down miR-5003. CONCLUSIONS: LncRNA RP11-789C1.1 inhibited EMT in GC through the RP11-789C1.1/miR-5003/E-cadherin axis, which could be a promising therapeutic target for GC.

MicroRNA-215 suppresses cell proliferation, migration and invasion of colon cancer by repressing Yin-Yang 1.

Colorectal cancer is one of the most common malignant tumors worldwide with rising incidence. MicroRNAs are small non-coding RNAs that implicate in multiple physiological or pathological processes. The aberrant expression of miRNA-215 (miR-215) has been illustrated in various types of cancers. However, the expression of miR-215 in human colon cancer and the biological roles of it remain largely unknown. We conducted this study to explore the expression and the function of miR-215 in human colon cancer. The results showed that miR-215 was remarkably downregulated in colon cancer tissues and cell lines. Overexpression of miR-215 by miR-215 mimic significantly inhibited colon cancer cell proliferation, migration and invasion while knockdown of miR-215 by miR-215 inhibitor exerted reverse effects. Furthermore, we newly identified Yin-Yang 1(YY1) as a direct target of miR-215 which could rescue the effects of miR-215 on colon cancer cells. In summary, our investigation revealed that miR-215 was downregulated in colon cancer and it suppressed colon cancer cell proliferation, migration and invasion by directly targeting YY1.

Role of Toll-like receptor 4 signaling in cutaneous chronic graft-versus-host disease.

Cutaneous damage is one of the characterized manifestations in chronic graft-versus-host disease (cGVHD). When local effective immunity in the skin is altered to a dysimmune reaction, cutaneous injuries occur. Toll-like receptor 4 signaling is regarded as a central mediator of inflammation and organ injury. In this study, we found that TLR4 mRNA in peripheral blood from patients with cutaneous cGVHD was markedly increased compared with that from non-GVHD patients and healthy controls. In addition, NF-κB expression, TLR4 downstream signaling, and TLR4-mediated cytokines, including IL-6 and ICAM-1, were upregulated. Moreover, ICAM-1 was widely distributed in skin biopsies from patients with cutaneous cGVHD. We also found that LPS induced TLR4-mediated NF-κB activation and IL-6 and ICAM-1 secretion in human fibroblasts in vitro. Thus, TLR4, NF-κB, IL-6, and ICAM-1 contribute to the inflammatory response that occurs in cutaneous cGVHD, indicating the TLR4 pathway may be a novel target for cutaneous cGVHD therapy.

Mesenchymal stromal cells treatment attenuates dry eye in patients with chronic graft-versus-host disease.

Cell therapy is a promising approach for the treatment of refractory ocular disease. This study investigated the efficacy of mesenchymal stromal cells (MSCs) for the treatment of dry eye associated with chronic graft-versus-host disease (cGVHD) and assessed the immunomodulatory effects of MSCs on regulatory CD8(+)CD28(-) T lymphocytes. A total of 22 patients with refractory dry eye secondary to cGVHD were enrolled. The symptoms of 12 out of 22 patients abated after MSCs transplantation by intravenous injection, improving in the dry eye scores, ocular surface disease index scores and the Schirmer test results. The clinical improvements were accompanied by increasing level of CD8(+)CD28(-) T cells, but not CD4(+)CD25(+) T cells, in the 12 patients who were treated effectively. They had significantly higher levels of Th1 cytokines (interleukin (IL)-2 and interferon-γ) and lower levels of Th2 cytokines (IL-10 and IL-4). In addition, CD8(+) T cells were prone to differentiation into CD8(+)CD28(-) T cells after co-culture with MSCs in vitro. In conclusion, transfusion of MSCs improved the clinical symptoms in patients (54.55%) with refractory dry eye secondary to cGVHD. MSCs appear to exert their effects by triggering the generation of CD8(+)CD28(-) T cells, which may regulate the balance between Th1 and Th2.

MicroRNA-188-5p targeting Forkhead Box L1 promotes colorectal cancer progression via activating Wnt/ß-catenin signaling.

Objective: MicroRNA-188-5p (miR-188) enhances oncologic progression in various human malignancies. This study aimed to explore its role in colorectal cancer (CRC). Materials and Methods: Human CRC tissues paired with normal tissues, and several CRC cell lines were utilized. Real-time quantitative PCR was applied to measure the expression of miR-188. Overexpression and knockdown were used to access the function of miR-188 and to investigate whether FOXL1/Wnt signaling mediates such function. The proliferation, migration and invasion of cancer cells were evaluated by CCK8, wound-healing and transwell assays, respectively. Whether FOXL1 acted as a direct target of miR-188 was verified by dual-luciferase reporter assays. Results: Levels of miR-188 were upregulated in CRC tissues than in paired-normal tissues, as well as in various CRC cell lines. High expression of miR-188 was strongly associated with advanced tumor stage, accompanied with significant tumor cell proliferation, invasion and migration. It was confirmed that FOXL1 played positive crosstalk between miR-188 regulation and downstream Wnt/ß-catenin signaling activation. Conclusions: All findings indicate that miR-188 promotes CRC cell proliferation and invasion through targeting FOXL1/Wnt signaling and could be served as a potential therapeutic target for human CRC in the future.

von Willebrand Factor as a Predictor for Transplant-Associated Thrombotic Microangiopathy.

CONCLUSION: von Willebrand factor is a useful predictor and prognostic measure for TA-TMA, which may help clinicians identify and manage this life-threatening disease earlier.

MicroRNA-188-5p targeting Forkhead Box L1 promotes colorectal cancer progression via activating Wnt/ß-catenin signaling.

MicroRNA-188-5p (miR-188) enhances oncologic progression in various human malignancies. This study aimed to explore its role in colorectal cancer (CRC). Human CRC tissues paired with normal tissues, and several CRC cell lines were utilized. Real-time quantitative PCR was applied to measure the expression of miR-188. Overexpression and knockdown were used to access the function of miR-188 and to investigate whether FOXL1/Wnt signaling mediates such function. The proliferation, migration and invasion of cancer cells were evaluated by CCK8, wound-healing and transwell assays, respectively. Whether FOXL1 acted as a direct target of miR-188 was verified by dual-luciferase reporter assays. Levels of miR-188 were upregulated in CRC tissues than in paired-normal tissues, as well as in various CRC cell lines. High expression of miR-188 was strongly associated with advanced tumor stage, accompanied with significant tumor cell proliferation, invasion and migration. It was confirmed that FOXL1 played positive crosstalk between miR-188 regulation and downstream Wnt/β-catenin signaling activation. All findings indicate that miR-188 promotes CRC cell proliferation and invasion through targeting FOXL1/Wnt signaling and could be served as a potential therapeutic target for human CRC in the future.

Extracellular vesicles derived from mesenchymal stem cells prevent skin fibrosis in the cGVHD mouse model by suppressing the activation of macrophages and B cells immune response.

OBJECTIVE: To illustrate the potential effects and mechanism of extracellular vesicles derived from mesenchymal stem cells (MSC-EVs) on fibrosis in sclerodermatous chronic graft-versus-host-disease (cGVHD) models after allogeneic hematopoietic stem cell transplantation. METHODS: We first observed the therapeutic effects of MSC-EVs on a minor histocompatibility haploidentical model of sclerodermatous cGVHD and the function of MSC-EVs on skin fibrosis and macrophage activation and the related pro-fibrosis protein. Additionally, we observed the effects of MSC-EVs on B cells, the T follicular helper cell (TFH) and germinal center B cell (GC B cells) interaction and the ratio of B cell activation factor (BAFF) to B cells in vivo. RESULTS: MSC-EVs treatment could alleviate the cGVHD scores and fibrosis of skin in sclerodermatous cGVHD mice, and this was associated with a reduction macrophage percentage in the skin and spleen, and a reduction in macrophage infiltration and TGF-ß and smad2 production in the skin. Additionally, MSC-EVs influence B cells immune response by blocking the TFH/GC B cells interaction and reducing the ratio of BAFF to B cells in vivo. CONCLUSION: MSC-EVs prevent the fibrosis of sclerodermatous cGVHD mouse model by suppressing the activation of macrophages and B cells immune response.

Extracellular vesicles from mesenchymal stem cells prevent contact hypersensitivity through the suppression of Tc1 and Th1 cells and expansion of regulatory T cells.

Extracellular vesicles (EVs) secreted by mesenchymal stem cells (MSC-EVs) are taken more seriously as immunomodulatory and anti-inflammatory agents. We studied the therapeutic effects of MSC-EVs on allergic contact dermatitis (ACD), a typical T cell-mediated disorder. A contact hypersensitivity (CHS) mouse model for ACD was established and treated by intravenous MSC-EVs injection. We found that human umbilical cord MSC-EVs could significantly prevent the pathology of CHS, including reduced ear swelling and leukocyte infiltration. Injection of MSC-EVs significantly inhibited CD8+IFN-γ+ cytotoxic T (Tc1) cells and CD4+IFN-γ+ type 1 helper T (Th1) cells, and reduced the level of pro-inflammatory Tumor Necrosis Factor-alpha (TNF-α) and interferon gamma (IFN-γ), and induced CD4+CD25+Foxp3+ regulatory T cells (Tregs) and the level of anti-inflammatory IL-10. In vitro, MSC-EVs also suppressed Tc1 and Th1 cells and induced Tregs and the related cytokines, further indicating the immune regulatory role of MSC-EVs. Interestingly, PKH26-labeled MSC-EVs were found to be directly internalized by CD3+ T cells, resulting in reduced signal transducer and activator of transcription 1 (STAT1) protein levels in vitro. In summary, MSC-EVs can prevent the onset of CHS by inhibiting Tc1 and Th1 immune responses and inducing the Tregs phenotype in vivo and in vitro. The mechanism by which MSC-EVs influence CD3+ T cells might partially involve targeting STAT1 in vitro. Therefore, MSC-EVs are ideal candidates for cell-free immunomodulatory therapy for T cell-mediated diseases such as ACD.

Correction to: A novel generation 1928zT2 CAR T cells induce remission in extramedullary relapse of acute lymphoblastic leukemia.

The original article [1] contains an error in authorship whereby author, Robert Weinkove's name is mistakenly inverted. The configuration noted in this Correction article should be considered instead along with author's updated affiliation.

Different genetic alteration of A20 in a Sézary syndrome case with Vα2-Jα22 T cell clone.

BACKGROUND: The comprehensive genetic alterations underlying the pathogenesis of Sézary syndrome (SS) remains largely unknown. Previous studies showed that alterations of tumor necrosis factor-α-induced protein 3 gene (TNFAIP3; A20) are frequent in SS. In this study, we characterized the mutation and polymorphisms of A20 in a case with SS and compared with the genetic feature of A20 in T-cell acute lymphoblastic leukemia (T-ALL). METHODS: Using a novel approach based on the combination of fine-tiling array comparative genomic hybridization ( and ligation-mediated polymerase chain reaction (LM-PCR) to identify SS clone, the polymorphisms in the A20 gene (promoter, exons 2-9 [coding region] and 3'UTR) were detected by PCR and sequencing. RESULTS: The malignant SS clone was identified as TCR Vα2-Jα22 rearrangement without deletion at the A20 loci (6q23-27 region) in the SS case. Six polymorphisms were identified, all of them are belonging to single nucleotide polymorphisms (SNPs) that are recorded in genebank: rs5029924, rs5029937, rs2230926, rs582757 and rs77191406, while rs2307859 was not identified in the SS sample, which is found in all T-ALL. The alteration pattern of A20 in this case seemed different from the T-ALL samples, in contrast, it is similar to the alteration of A20 in samples from rheumatoid arthritis or systemic lupus erythematosus with poor clinical outcome and cancer developing. CONCLUSIONS: The genetic alteration of A20 in the SS case was different from the T-ALL samples and similar to the cases with refractory autoimmune disease and related to tumorigenesis. The findings lead to discuss whether such SNPs of A20 may link the refractory autoimmune inflammation and the tumorigenesis.

Emerging role of C5a/C5aR IL-17A axis in cGVHD.

Chronic graft-versus-host disease (cGVHD) manifests with features characteristic of autoimmune disease with organs attacked by pathogenic Th17 cells. However, the mechanism of Th17 cells generation in the setting of cGVHD is still unclear. Here we defined C5a/C5aR-IL-17Aaxis as a novel signaling that required in the pathologies of cGVHD. We firstly found a positive link between complement activation and the Th17 cells in patients with cGVHD. C5a, a critical component of complements, promoted the generation of Th17 cells in vitro and inhibition of the receptor for C5a (C5aR) reduced the Th17-bias response. Of note, C5aR blockade by PMX53 could suppress the generation of IL-17A-expressing Th17 cells and retard the onset and progression of cGVHD in vivo. Overall, our results provide new mechanistic insights that activation of C5a-C5aR signaling was required for IL-17A-induced immune responses in cGVHD and define novel molecular targets for developing effective therapeutics for cGVHD.

A potent immunomodulatory role of exosomes derived from mesenchymal stromal cells in preventing cGVHD.

BACKGROUND: Mesenchymal stromal cells (MSCs) are a promising therapy for preventing chronic Graft-Versus-Host Disease (cGVHD) due to their potent immunomodulatory properties. However, the safety concerns regarding the use of MSCs remain unsolved, and conflicting effects are observed due to the heterogeneity of MSCs. Recently, exosomes were shown to mediate the paracrine effects of MSCs, making it a potential candidate for cell-free therapies. The aim of this study is to investigate the efficacy and safety of MSCs-derived exosomes (MSCs-exo) in an established cGVHD mouse model. METHODS: Bone marrow (BM)-derived MSCs were cultured, and the supernatants of these cultures were collected to prepare exosomes using ultracentrifugation. Exosomes from human dermal fibroblasts (Fib-exo) were used as a negative control. The cGVHD model was established, and tail vein injections of MSCs-exo or Fib-exo were administered once per week for 6 weeks. The symptoms and signs of cGVHD were monitored, and histopathological changes were detected by hematoxylin and eosin and Masson staining. The effects of MSCs-exo on Th17, Th1, and Treg were evaluated by flow cytometry, qPCR, and Luminex. In addition, human peripheral blood mononuclear cells (PBMCs) were stimulated and treated with MSCs-exo in vitro. IL-17-expressing Th17 and IL-10-expressing Treg were evaluated by flow cytometry, qPCR, and ELISA. RESULTS: We found that MSCs-exo effectively prolonged the survival of cGVHD mice and diminished the clinical and pathological scores of cGVHD. Fibrosis in the skin, lung, and liver was significantly ameliorated by MSCs-exo application. In MSCs-exo treated mice, activation of CD4+ T cells and their infiltration into the lung were reduced. Of note, MSCs-exo exhibited potent immunomodulatory effects via the inhibition of IL-17-expressing pathogenic T cells and induction of IL-10-expressing regulatory cells during cGVHD. The expressions of Th17 cell-relevant transcription factors and pro-inflammatory cytokines was markedly reduced after MSCs-exo treatment. In vitro, MSCs-exo blocked Th17 differentiation and improved the Treg phenotype in PBMCs obtained from healthy donors and patients with active cGVHD, further indicating the regulatory effect of MSCs-exo on GVHD effector T cells. CONCLUSIONS: Our data suggested that MSCs-exo could improve the survival and ameliorate the pathologic damage of cGVHD by suppressing Th17 cells and inducing Treg. This finding provides a novel alternative approach for the treatment of cGVHD.

A novel generation 1928zT2 CAR T cells induce remission in extramedullary relapse of acute lymphoblastic leukemia.

BACKGROUND: Anti-CD19 chimeric antigen receptor (CAR) T cells have shown promise in the treatment of B cell acute lymphocytic leukemia (B-ALL). However, its efficacy in B-ALL patients with extramedullary involvement is limited due to poor responses and neurotoxicity. Here, we utilized a third generation of CAR T cell vector, which contains the Toll/interleukin-1 receptor (ITR) domain of Toll-like receptor 2 (TLR2), to generate 1928zT2 T cells targeting CD19, and evaluated the efficacy of 1928zT2 T cells in relapse or refractory B-ALL patients with extramedullary involvement. METHODS: 1928zT2 T cells were generated by 19-28z-TLR2 lentiviral vector transfection into primary human T lymphocytes. The anti-leukemia effect of 1928zT2 T cells were determined by killing assays and in xenografts. Three patients diagnosed as relapse or refractory ALL with extramedullary involvement were infused with 1928zT2 T cells, and the clinical responses were evaluated by BM smear, B-ultrasonography, PET/CT, histology, flow cytometry, qPCR, ELISA, and luminex assay. RESULTS: 1928zT2 T cells exhibited enhanced effector function against CD19+ leukemic cells in vitro and in a xenograft model of human extramedullary leukemia. Notably, the 1928zT2 T cells eradicated extramedullary leukemia and induced complete remission in the three relapse and refractory ALL patients without serious adverse effects. 1928zT2 T cells expanded robustly in the circulation of these three patients and were detected in the cerebrospinal fluid of patient 3. These three patients experienced cytokine release syndrome (CRS) with grade 2 or 3, which remitted spontaneously or after tocilizumab treatment. None of the three patients suffered neurotoxicity or needed further intensive care. CONCLUSIONS: Our results demonstrate that 1928zT2 T cells with TLR2 incorporation augment anti-leukemic effects, particularly for eradicating extramedullary leukemia cells, and suggest that the infusion of 1928zT2 T cells is an encouraging treatment for relapsed/refractory ALL patients with extramedullary involvement. TRIAL REGISTRATION: ClinicalTrials.gov identifier NCT02822326 . Date of registration: July 4, 2016.

Attenuation of cGVHD by C5a/C5aR blockade is associated with increased frequency of Treg.

C5aR signaling plays an important role in the regulation of T cell activation and alloimmune responses in chronic graft-versus-host disease (cGVHD). However, direct evidence of this modulation and the efficacy of C5aR blockade in the treatment of cGVHD have not been demonstrated. We observed higher expression of C5aR on both monocytes and T cells of patients with cGVHD compared with healthy controls and non-GVHD patients after allogeneic hematopoietic stem cell transplantation. Our data also demonstrated a significant negative correlation between C5aR expression and regulatory T cells (Treg) frequency in cGVHD patients, indicating a potential role of C5aR in the generation and regulation of Treg. In addition, an in vitro experiment revealed C5aR deficiency promoted the development of Treg whereas C5a activation abolished the differentiation of Treg. Importantly, we found C5aR blockade by PMX53 attenuated the pathology of cGVHD and improved the survival of cGVHD mice. PMX53 had a direct regulatory effect on Treg commitment and increased TGF-ß1 expression. Thus, C5aR signaling may induce and intensify cGVHD by down-regulating Treg induction. The modulation of C5aR activation by PMX53 may provide a potential therapy for cGVHD.

Persistent donor derived Vδ4 T cell clones may improve survival for recurrent T cell acute lymphoblastic leukemia after HSCT and DLI.

The outcome for T-cell acute lymphoblastic leukemia (T-ALL) in relapse after hematopoietic stem cell transplantation (HSCT) is quite poor, while, both donor lymphocytes infusion (DLI) and adoptively infusion of γδ T cells in leukemia patients after HSCT have demonstrated good results in prolonging survival time of patients. Here, we reported a T-ALL case who experienced three relapses and received HSCT and DLI with an overall survival (OS) time lasting for more than seven years. Based on our previous identification of a leukemic and reactive clone in this patient, continual γδ T cell repertoire monitoring affirmed that the same Vδ5 leukemic clone existed in most samples from the patient, particularly including a sample taken at the time of the third T-ALL relapse, while it could not be detected in the donor sample. In addition, an identical Vδ4 monoclonal T cell that proliferated in the recipient for several years was confirmed to come from the donor graft, and its expression level significantly increased in third leukemia recurrence. These results indicate that clonally expanded Vδ4 T cells may represent a reconstituted γδ T cell repertoire after HSCT, which also hints to a relatively better outcome for this case. Based on this case study, we recommend DLI should be as a treatment strategy for patients who achieve CR or relapse from HSCT. Moreover, dynamically monitoring the TCR repertoire in patients who receive HSCT will benefit in supervising of malignant clone evolution and residue, identifying T cell clones mediate anti-infection, GvHD or GvL.

Arsenic induced complete remission in a refractory T-ALL patient with a distinct T-cell clonal evolution without molecular complete remission: A case report.

Currently, arsenic trioxide therapy is widely used for the treatment of acute promyelocytic leukemia (APL), relapsed and refractory adult T-cell leukemia/lymphoma and myelodysplastic syndrome. Regarding the broad antitumor activity of arsenic, certain studies have been undertaken to test its efficacy in treating acute T-cell lymphoblastic leukemia (T-ALL) cell lines and patients; however, to the best of our knowledge, no reports document that arsenic is able to induce the remission of T-ALL patients. The present study reports the case of young male patient diagnosed with T-ALL, with no significant response to common chemotherapy regimens, who finally achieved complete remission without minimal residual disease (as detected by flow cytometry) due to arsenic treatment. This result is encouraging, and the present study has shown that malignant TCRαß+ cell clones can be detected at the molecular level using reverse transcription-polymerase chain reaction (PCR) combined with the GeneScan technique. The result is mainly based on the T-cell receptor (TCR) Vß1 clone (a 190-base pair PCR product that with the same complementarity determining region 3 length can be detected for all samples collected during various statuses) and on undetectable TCR Vγ subfamily members, at the time of disease diagnosis. It is important to analyze the dynamically changing TCR pool in leukemia patients during therapy. Although the molecular mechanism through which arsenic contributes to malignant clone elimination remains unclear in the case presented, the use of arsenic is expected to be effective for clinically treating refractory and relapsed T-ALL patients.

[Effectiveness of CLAT Protocol for Treating Patients with Refractory Acute Myeloid Leukemia].

OBJECTIVE: To explore the clinical efficacy and toxicity of CLAT protocol (cladribine, cytarabine and topotecan) for treating patients with refractory acute myeloid leukemia (R-AML). METHODS: A total of 18 patients with R-AML (median age 37 years, range 18 to 58 years; male n = 16, female n = 2) were treated with CLAT protocol, which consisted of cladribine 5 mg/m(2)/d, i.v. on days 1-5, cytarabine 1.5 g/m(2)/d, i.v. on days 1-5, topotecan 1.25 mg/m(2)/d, i.v. on days 1-5 and G-CSF 300 µg/d subcutaneous injection on day 6 until neutrophile granulocyte recovery. RESULTS: Out of 18 patients 2 died of severe infection before the assessment. Among 16 evaluated patients, 10 (55.6%) achieved complete remission (CR), and 2 (11.1%) achieved partial remission (PR), the overall response rate was 66.7%, the rest 4 patients did not respond (NR). The median overall survival time and DFS for the CR patients was 9.5 months (95%CI: 6.7-16.64) and 9.5 months (95%CI: 6.1-16.7) respectively. The 1 year OS and DFS rates were 45% and 46.9%, respectively. All patients developed grade 4 of granulocytopenia and thrombocytopenia, the median duration was 13 (range 2 to 21) days and 12 days (range 2 to 21), respectively, all patients developed infection, 2 patients died of severe infection. The most common non-hematological side effects included nausea, vomiting, diarrhoea, rash, aminotransferase or bilirubin elevation and were grade 1 to 2. CONCLUSION: The CLAT protocol seems to have promising for the treatment of refractory AML patients, and patients well tolerated. This CLAT protocol offers an alternative treatment for R-AML patients who received severe intensive treatment, especially with anthracycline-containing chemotherapy.