A bioinformatic analysis found low expression and clinical significance of ATF4 in breast cancer.

Background: Activating Transcription Factor 4 (ATF4) expression exhibits differential patterns across different types of tumors. Besides, the pathogenesis of breast cancer is complex, and the exact relationship between ATF4 and ATF4 remains uncertain. Methods: The analysis of ATF4 expression was conducted by utilizing The Cancer Genome Atlas (TCGA) pan-cancer data, while the gene expression profile of breast cancer was checked by the comprehensive database-Gene Expression Omnibus database. In order to gain a more comprehensive understanding of the specific cell types that exhibit ATF4 expression within the microenvironment of breast cancer, we conducted a single-cell analysis of ATF4 using two distinct datasets of human breast cancer (GSE114717 and GSE11088, respectively). The spatial distribution of ATF4 within a tissue was demonstrated based on datasets obtained from the Human Protein Atlas (HPA) and SpatialDB. The clinical prognostic significance of ATF4 was assessed by analyzing clinical survival data obtained from TCGA, GSE4830, and GSE25055 datasets. We used the R package clusterProfiler to carry out an enrichment analysis of ATF4. We assessed how ATF4 impacts the growth and movement of breast cancer cell lines. We manipulated ATF4 levels using plasmid transfection techniques. Results: The expression of ATF4 was found to be suboptimal and demonstrated a significant correlation with enhanced disease-specific survival (p = 0.012) and overall survival (p = 0.032) in breast cancer as well as other malignancies. We conducted an analysis to investigate the interaction between the infiltration level of immune cells and the expression of ATF4, using samples obtained from TCGA with known immune cell infiltration scores. Furthermore, a notable positive correlation exists between the elevated expression of ATF4 and immune-related genomes, specifically those associated with chemokine as well as immunity. Subsequent examination revealed a notable augmentation in the cytodifferentiation of T cells into regulatory T (Treg) cells within tissues exhibiting elevated levels of ATF4 expression. ATF4 exhibits notable upregulation in the MDA-MB-231 cell, thereby exerting a substantial impact on cell proliferation and migration upon its knockdown. Conversely, the overexpression of ATF4 in the MCF7 Luminal A breast cancer cell line can also modulate cellular function. Conclusions: Our study suggests that ATF4 helps T cells differentiate into Treg cells in breast cancer. ATF4 can represent a clinically useful biomarker to predict the overall survival rate, especially in patients with different subtypes of breast cancer. Provide certain guidance value for the development of targeted drugs or inhibitors targeting ATF4.

Ribosomal protein S3 mediates drug resistance of proteasome inhibitor: potential therapeutic application in multiple myeloma.

Multiple myeloma (MM) remains incurable due to drug resistance. Ribosomal protein S3 (RPS3) has been identified as a non-Rel subunit of NF-κB. However, the detailed biological roles of RPS3 remain unclear. Here, we report for the first time that RPS3 is necessary for MM survival and drug resistance. RPS3 was highly expressed in MM, and knockout of RPS3 in MM inhibited cell growth and induced cell apoptosis both in vitro and in vivo. Overexpression of RPS3 mediated the proteasome inhibitor resistance of MM and shortened the survival of MM tumor-bearing animals. Moreover, our present study found an interaction between RPS3 and the thyroid hormone receptor interactor 13 (TRIP13), an oncogene related to MM tumorigenesis and drug resistance. We demonstrated that the phosphorylation of RPS3 was mediated by TRIP13 via PKCδ, which played an important role in activating the canonical NF-κB signaling and inducing cell survival and drug resistance in MM. Notably, the inhibition of NF-κB signaling by the small-molecule inhibitor targeting TRIP13, DCZ0415, was capable of triggering synergistic cytotoxicity when combined with bortezomib in drug-resistant MM. This study identifies RPS3 as a novel biomarker and therapeutic target in MM.

A novel pterostilbene compound DCZ0825 induces macrophage M1 differentiation and Th1 polarization to exert anti-myeloma and immunomodulatory.

Multiple myeloma (MM) is an incurable and recurrent malignancy characterized by abnormal plasma cell proliferation. There is an urgent need to develop effective drugs in MM. DCZ0825 is a small molecule compound derived from pterostilbene with direct anti-myeloma activity and indirect immune-killing effects though reversal of the immunosuppression. DCZ0825 inhibits the activity and proliferation of MM cells causing no significant toxicity to normal cells. Using flow cytometry, this study found that DCZ0825 induced caspase-dependent apoptosis in MM cells and arrested the cell cycle in the G2/M phase by down-regulating CyclinB1, CDK1 and CDC25. Moreover, DCZ0825 up-regulated IRF3 and IRF7 to increase IFN-γ, promoting M2 macrophages to transform into M1 macrophages, releasing the immunosuppression of CD4T cells and stimulated M1 macrophages and Th1 cells to secrete more INF-γ to form immune killing effect on MM cells. Treatment with DCZ0825 resulted in an increased proportion of positive regulatory cells such as CD4T, memory T cells, CD8T, and NK cells, with downregulation of the proportion of negative regulatory cells such as Treg cells and MDSCs. In conclusion, DCZ0825 is a novel compound with both antitumor and immunomodulatory activity.

Berberine derivative DCZ0358 induce oxidative damage by ROS-mediated JNK signaling in DLBCL cells.

The most common neoplasm among adult lymphomas is diffuse large B-cell lymphoma (DLBCL), typically characterized by pain-free and progressive lymph node enlargement. Due to high heterogeneity of DLBCL, 30-40 % of patients are resistant to R-CHOP standard chemoimmunotherapy. DCZ0358 is a new compound designed and synthesized from berberine by our group and the molecular mechanism by which it inhibited DLBCL growth has attracted our widespread attention. In this study, we employed the CCK8 assay to reveal that DCZ0358 inhibited proliferation in a dependent manner of time and dosage of DLBCL cells. Moreover, flowcytometry and western blot results showed that DCZ0358 downregulated the expression of CDK4, CDK6 and CyclinD1 to block cell cycle progression in G0/G1 phase. Furthermore, DCZ0358 enhanced mitochondrial membrane potential depolarization, promoted mitochondrial permeability transport pore openness, increased cytoplastic Ca2+ levels and decreased intracellular adenosine triphosphate production, which led to mitochondrial dysfunction. In particular, DCZ0358 treatment triggered cell apoptosis and elevated intracellular reactive oxygen species (ROS) levels, which subsequently mediated JNK pathway activation. Further research indicated the pre-treatment with ROS scavenger N-acetylcysteine (NAC) and JNK inhibitor SP600125 could partially attenuate apoptosis and DNA damage triggered by DCZ0358. Most importantly, DCZ0358 exhibited synergistic anti-tumor effects when combined with etoposide, a common clinical anti-DLBCL drug, both in vitro and certainly in vivo. Above results demonstrated anti-tumor molecular mechanism of DCZ0358 in DLBCL cells and highlighted the ROS/JNK/DNA damage pathway as a potential target in therapies, which have implications for the development of more effective clinical treatments for DLBCL.

The novel norcantharidin derivative DCZ5417 suppresses multiple myeloma progression by targeting the TRIP13-MAPK-YWHAE signaling pathway.

BACKGROUND: Multiple myeloma (MM), an incurable disease owing to drug resistance, requires safe and effective therapies. Norcantharidin (NCTD), an active ingredient in traditional Chinese medicines, possesses activity against different cancers. However, its toxicity and narrow treatment window limit its clinical application. In this study, we synthesized a series of derivatives of NCTD to address this. Among these compounds, DCZ5417 demonstrated the greatest anti-MM effect and fewest side effects. Its anti-myeloma effects and  the mechanism were further tested. METHODS: Molecular docking, pull-down, surface plasmon resonance-binding, cellular thermal shift, and ATPase assays were used to study the targets of DCZ5417. Bioinformatic, genetic, and pharmacological approaches were used to elucidate the mechanisms associated with DCZ5417 activity. RESULTS: We confirmed a highly potent interaction between DCZ5417 and TRIP13. DCZ5417 inhibited the ATPase activity of TRIP13, and its anti-MM activity was found to depend on TRIP13. A mechanistic study verified that DCZ5417 suppressed cell proliferation by targeting TRIP13, disturbing the TRIP13/YWHAE complex and inhibiting the ERK/MAPK signaling axis. DCZ5417 also showed a combined lethal effect with traditional anti-MM drugs. Furthermore, the tumor growth-inhibitory effect of DCZ5417 was demonstrated using in vivo tumor xenograft models. CONCLUSIONS: DCZ5417 suppresses MM progression in vitro, in vivo, and in primary cells from drug-resistant patients, affecting cell proliferation by targeting TRIP13, destroying the TRIP13/YWHAE complex, and inhibiting ERK/MAPK signaling. These results imply a new and effective therapeutic strategy for MM treatment.

Dihydrocelastrol induces antitumor activity and enhances the sensitivity of bortezomib in resistant multiple myeloma by inhibiting STAT3-dependent PSMB5 regulation.

Multiple myeloma (MM) is characterized by excessive aggregation of B-cell-derived malignant plasma cells in the hematopoietic system of bone marrow. Previously, we synthesized an innovative molecule named dihydrocelastrol (DHCE) from celastrol, a triterpene purified from medicinal plant Tripterygium wilfordii. Herein, we explore the therapeutic properties and latent signal transduction mechanism of DHCE action in bortezomib (BTZ)-resistant (BTZ-R) MM cells. In this study, we first report that DHCE shows antitumor activities in vitro and in vivo and exerts stronger inhibitory effects than celastrol on BTZ-R cells. We find that DHCE inhibits BTZ-R cell viability by promoting apoptosis via extrinsic and intrinsic pathways and suppresses BTZ-R MM cell proliferation by inducing G0/G1 phase cell cycle arrest. In addition, inactivation of JAK2/STAT3 and PI3K/Akt pathways are involved in the DHCE-mediated antitumor effect. Simultaneously, DHCE acts synergistically with BTZ on BTZ-R cells. PSMB5, a molecular target of BTZ, is overexpressed in BTZ-R MM cells compared with BTZ-S MM cells and is demonstrated to be a target of STAT3. Moreover, DHCE downregulates PSMB5 overexpression in BTZ-R MM cells, which illustrates that DHCE overcomes BTZ resistance through increasing the sensitivity of BTZ in resistant MM via inhibiting STAT3-dependent PSMB5 regulation. Overall, our findings imply that DHCE may become a potential therapeutic option that warrants clinical evaluation for BTZ-R MM.

A novel alkaloid compound, DCZ0358, exerts significant antitumor activity in bortezomib-resistant multiple myeloma cells through inhibition of JAK2/STAT3 pathway.

Multiple myeloma (MM), the second most common haematological malignancy, is currently incurable because patients often develop multiple drug resistance and experience subsequent relapse of the disease. This study aims to identify a potential therapeutic agent that can counter bortezomib (BTZ) resistance in MM. DCZ0358, a novel alkaloid compound, is found to exert potent cytotoxic effects against BTZ-resistant MM cells in vivo and in vitro. The anti-myeloma activity of DCZ0358 is associated with inhibition of cell proliferation, promotion of cell apoptosis via caspase-mediated apoptotic pathways, and induction of G0/G1 phase arrest via downregulation of cyclin D1, CDK4, and CDK6. Further investigation of the molecular mechanism shows that DCZ0358 suppresses the JAK2/STAT3 signaling pathway. In conclusion, DCZ0358 can successfully counter BTZ resistance in MM cells. This study provides evidence that warrants future preclinical assessments of DCZ0358 as a therapeutic agent against BTZ resistance in MM.

Predictive Value Analysis of Serum Ig A, Ig G, and TNF-α in Recurrence of Multiple Myeloma.

Objective: The study is aimed at analyzing the predictive value of serum Ig A, Ig G, and TNF-α in the recurrence of multiple myeloma (MM). Methods: 136 patients with MM treated in our hospital from January 2010 to January 2017 were followed up for 5 years. Finally, 100 patients who met the inclusion and exclusion criteria and had the complete follow-up visit were selected as the study subjects, with the recurrence of MM as endpoint event, and the observation was taken until the occurrence of endpoint event in patients or the termination of this study. They were divided into the recurrence group (RG) and the nonrecurrence group (NRG) according to whether the endpoint event occurred. The venous blood of patients was collected at the first diagnosis and subsequent visit (at the time of recurrence or termination of the study) to measure the Ig A and Ig G using a full automatic special protein analyzer and the TNF-α level by enzyme-linked immunosorbent assay. The data obtained in this study were analyzed by univariate analysis to choose the factors with difference in statistical significance to draw the ROC curve, and the areas under the curve (AUC) were recorded to analyze the potential mechanism of Ig A, Ig G, and TNF-α in predicting the recurrence of MM. Results: After follow-up visit, there were 62 patients with recurrence (62.0%) and 38 patients without recurrence (38.0%), with no obvious difference in gender, age, body weight, and immune classification between the two groups (P > 0.05). Compared with the NRG, the levels of soluble interleukin-2 receptor (sIL-2R) and ß 2-microglobulin (ß 2-MG) in the RG at the first diagnosis were distinctly higher (P < 0.001); the levels of Ig A, Ig G, and TNF-α in the RG at the first diagnosis were visibly higher (P < 0.05); and the levels of Ig A, Ig G, and TNF-α in the RG at the subsequent visit were clearly higher (P < 0.05). There was a correlation between Ig G, Ig A, and TNF-α and ß 2-MG at the first diagnosis and the subsequent visit (P < 0.05); there was a correlation between Ig G and TNF-α, and sIL-2R at the first diagnosis and the subsequent visit (P < 0.05); and there was a correlation between Ig A and sIL-2R at the subsequent visit (P < 0.05). The AUC of Ig G, Ig A, and TNF-α in predicting the MM at the first diagnosis were 0.772, 0.776, and 0.778, respectively. Conclusion: The serum Ig A, Ig G, and TNF-α had a predictive value in the recurrence of MM, and TNF-α was correlated with sIL-2R and ß 2-MG, with the highest AUC and the best predictive value.

Influence of demethylation on regulatory T and Th17 cells in myelodysplastic syndrome.

Myelodysplastic syndrome (MDS) represents a heterogeneous hematopoietic disorder in which mature blood cells are derived from an abnormal multipotent progenitor cell. The current therapy for MDS involves repeated cycles of DNA methyltransferase (DNMT) inhibitors, particularly the demethylation drug 5-azacytidine (5-azaC) which has been shown to increase the survival of patients with high-risk MDS. The mechanisms behind the therapeutic effects of 5-azaC are not yet clear. In this study the effect of 5-azaC on the development of regulatory T cells (Tregs) and T-helper 17 (Th17) cells was investigated. The numbers of CD4+ T-cell subsets in 30 patients with intermediate-2/high-risk MDS were serially assessed at diagnosis and following 5-azaC treatment. The number of FoxP3+ Tregs was significantly higher after 3 months of therapy. However, there was no statistical difference in the number of Th17 cells following treatment. In vitro, 5-azaC enhanced the overall proportion of Tregs, but not Th17, in CD4+ T cells from patients with MDS. Addition of 5-azaC reduced the proliferative capacity of Tregs, suggesting that the increase in Tregs was due to conversion of conventional CD25- cells, rather than proliferation of CD25+FoxP3+ cells. The FoxP3 expression in 5-azaC-treated T effectors was also increased. Interestingly, while Tbet and RORγT mRNA transcription had no obvious changes, due to the demethylation of the FoxP3 promoter, these findings are important in associating the induction of DNA hypomethylation and the clinical response to 5-azaC.

[Distribution of CD45RO⁺ T and CD45RA⁺ T Cells in Peripheral Blood of Patients with Peripheral T Cell Lymphoma].

OBJECTIVE: To investigate the clinical significance of memory T cells (CD45RO⁺ T) and the initial T cells (CD45RA⁺ T) distribution in peripheral blood of patients with peripheral T-cell lymphoma (PTCL). METHODS: A total of 27 patients diagnosed as PTCL in our hospital from February 2010 to February 2014 were collected in this study; whereas 30 healthy people were enrolled as control. The distribution of CD45RO⁺ T and CD45RA⁺ T cells were detected seperately in each group, and the results were analysed further. RESULTS: The expression of T cell antigens in lymphnodes of PTCL patients were diverse: the CD4⁺ T cells were the main immune phenotype, while the B cell-related antigen was not expressed. The CD4⁺/CD8⁺, CD4⁺ CD45RO⁺ T in the peripheral blood of PTCL patients were significantly lower than that in normal group (P < 0.05); while the CD4, CD45RA⁺ T, CD8⁺ CD45RA⁺ T and CD8⁺ CD45RO⁺ T were significantly higher than that in normal group (P < 0.05). The patients in stage I/II had higher CD4⁺/CD8⁺, CD4⁺ CD45RO⁺ T than those in stage III/IV (P < 0.05), whereas the CD4⁺ CD45RA⁺ T, CD8⁺ CD45RA⁺ T and CD8⁺ CD45RO⁺ T were significantly lower than those in the stage III/IV patients (P < 0.05). CONCLUSION: The distributions of CD45RA⁺ T and CD45RO⁺ T in PTCL patients are quite different, and the corresponding treatment might be adopted according to the different distribution of these cells, so as to improve the diagnosis and prognosis of PTCL.

Immunophenotypic characterization of CD45RO+ and CD45RA+ T cell subsets in peripheral blood of peripheral T cell lymphoma patients.

To study the distribution profile of CD45RO(+) and CD45RA(+) T cells in the peripheral blood of peripheral T cell lymphoma (PTCL) patients and its clinical significance. 27 patients with PTCL were enrolled in this study, together with 30 healthy individuals as the control group. Flow cytometry analysis was employed to examinate the differences in the distribution of CD45RO(+) and CD45RA(+) T cells in peripheral blood between two groups. In PTCL patient's lymphnode tissues, the T cell population displayed diverse antigenic expression, with CD4(+) T cells as the major subset. No B cell-related antigen was expressed. The percentage of CD4(+)/CD8(+) and CD4(+)CD45RO(+) T cells in patients' peripheral blood were significantly lower than that in the control samples, while the percentage of CD4(+)CD45RA(+), CD8(+)CD45RA(+), and CD8(+)CD45RO(+) T cells in patients' peripheral blood were significantly higher than that in the control samples. The percentage of CD4(+)/CD8(+), CD4(+)CD45RO(+) cells in stage I/II PTCL patients' peripheral blood were significantly higher than that in the samples from patients with stage III/IV PTCL. The percentage of CD4(+)CD45RA(+), CD8(+)CD45RA(+), and CD8(+)CD45RO(+) T cells were notably lower than that in the samples from III/IV period PTCL patients. Both CD45RO(+) and CD45RA(+) T cells play important roles in the process of PTCL. The immunophenotypic profile from this study will help to develop the differential diagnosis and treatment of PTCL patients in the future, and improve the accuracy rate of diagnosis and to ameliorate the prognosis.

Effects of lentivirus mediated STAT3 silencing on human chronic myeloid leukemia cells and leukemia mice.

OBJECTIVE: To investigate the effects of lentivirus mediated STAT3 silencing on human chronic myeloid leukemia cells (K562) and the growth of chronic myeloid leukemia mice as well as to explore the potential mechanisms. METHODS: Unbtreated K562 cells (CON), blank lentivirus transfected K562 cells (NC) and K562 cells expressing STAT3 siRNA (STAT3 siRNA) were injected into SCID mice to establish the chronic myeloid leukemia model in mice. The growth, peripheral white blood cell count and spleen index in these mice were determined. RESULTS: In vitro experiment showed, when compared with control group, the interference efficiency of STAT3 expression was as high as 97.5% in K562 cells. Western blot assay revealed that the expression of c-Myc, Bcl-xL and Cyclin D1 reduced by 17.01%, 7.3% and 6.82%, respectively, showing significant difference when compared with control group (P < 0.01). These findings were consistent with those from fluorescence quantitative PCR. In vivo experiment showed the body weight of mice reduced progressively and the peripheral white blood cell count increased gradually in control group, accompanied by dragging hind limbs and progressive enlargement of the spleen. The body weight remained unchanged, peripheral white blood cell count reduced gradually and the spleen did not enlarge in mice treated with STAT3 siRNA expressing cells. CONCLUSION: Lentivirus mediated STAT3 silencing may inhibit the expression of its downstream genes (c-Myc, Bcl-xL and Cyclin D1) related to cell proliferation, apoptosis and cycle to suppress the malignant biological behaviors, and STAT3 silencing also inhibit the leukemogenic potency of K562 cells in mice.

Successful treatment of paraganglioma with sorafenib: a case report and brief review of the literature.

INTRODUCTION: To date, no effective systemic therapies have been made available for paraganglioma. However, multiple mutations in susceptibility genes have been identified that are potential targets for sorafenib, an oral multitargeted tyrosine-kinase inhibitor. CASE PRESENTATION: We report the case of a 69-year-old Chinese man with mediastinal paraganglioma that had metastasized to the bone. The paraganglioma responded to sorafenib, a novel multi-tyrosine kinase inhibitor that targets angiogenesis, the Raf-kinase pathway, the platelet-derived growth factor Ret, and c-Kit. The patient was diagnosed as having paraganglioma after biopsy of the mediastinal mass. We first treated the patient with radiotherapy. Then he tolerated an etoposide-and-cisplatin chemotherapy regimen. Subsequently, he received 6 months of maintenance treatment with sorafenib (400 mg twice daily). A dramatic reduction in tumor volume was observed. At present, the patient has achieved a partial response, and his clinical status remains unchanged. CONCLUSION: We suggest that sorafenib should be further investigated in the management of patients with paraganglioma.

The rs2233678 polymorphism in PIN1 promoter region reduced cancer risk: a meta-analysis.

BACKGROUND: Published evidence suggests that the rs2233678 (-842 G>C) polymorphism in the PIN1 (peptidyl-prolyl cis/trans somerase NIMA-interacting 1) promoter region may be associated with cancer risk; however, the conclusion is still inconclusive. METHODS: We conducted a meta-analysis to determine whether -842 G>C polymorphism was associated with cancer risk. Odds ratio (OR) and 95% confidence intervals (95% CI) were used to assess the strength of association. Genotype distribution data and adjusted ORs were collected to calculate the pooled ORs. Meta-regression was conducted to detect the source of heterogeneity. Publication bias was evaluated by Egger's test and Begg's test. RESULTS: A total of 11 eligible studies, including 9280 participants, were identified and analyzed. Overall, we found that carriers of the -842 C allele were associated with significantly decreased cancer risk (C vs. G, OR = 0.750, 95% CI: 0.639-0.880, P(heterogeneity )= 0.014, estimated by genotype distribution data; CC+GC vs. GG, OR = 0.668, 95% CI: 0.594-0.751, P(heterogeneity) = 0.638, estimated by adjusted ORs). No evidence of publication bias was observed. Meta-regression revealed that ethnicities (p = 0.021) and sample size (p = 0.02) but not sources of control (p = 0.069) were the source of heterogeneity. CONCLUSION: These results suggest that the PIN1 rs2233678 (-842 G>C) polymorphism significantly reduces cancer risk.

Ultrafast generation of thick poly(ether amine) (PEA) brush on a gold surface and its protein resistance.

We demonstrate an ultrafast, convenient and universal approach to fabricate a poly(ether amine) (PEA) brush on a gold surface, which exhibited excellent performance of protein resistance with long-term stability.

[Clonal kinetic proliferative change of TCR Vbeta subfamilies in peripheral blood of patients transplanted with allogeneic hematopoietic stem cells and its relation to GVHD].

This study was purposed to investigate the dynamic change of clonal proliferation of T cell receptor V subfamilies in peripheral blood of patients received allo-hematopoietic stem cell transplantation (allo-HSCT) and to analyze the relationship between T cell clonal proliferative changes and GVHD. The peripheral blood mononuclear cell samples from 70 cases (17 GVHD patients) undergoing allo-PBCST patients were detected for CDR3 (complementarity determining region 3 repertoire analysis of T cell receptor Vbetagene) using reverse-transcriptase-polymerase chain reaction (RT-PCR). The products were further analyzed by genescan to identify T cell clonality. The results showed that the patients of HSCT generally passed through a transformation from monoclone to polyclone. At day 60 - 90 after HSCT, half of the cases were monoclonal and the remainders were polyclonal. After 120 days, most of patients without GVHD transferred into polyclones, however, patients with GVHD remained monoclonal after one year because of immunosuppressive agents and GVHD itself. The peripheral blood of GVHD patients mainly expressed monoclone/biclone at the time of target organ damage conspicuously, after medication intervention, partial monoclone or bioclone expressed TCR Vbeta subfamilies were diverted to polyclonal expression. It is concluded that the T cells present clonal proliferation and T cell receptors are prone to be used when patients are in earlier period of transplantation or with GVHD especially. The expression of TCR Vbeta subfamilies can return to normal polycloning along with the recovery of hematopoiesis and immunity in patients.

[Recipient lymphopenia state enhances the expansion and anti-leukemia effect of leukemia specific cytotoxic T lymphocytes].

OBJECTIVE: To determine the role of recipient lymphopenia state in the expansion and function of leukemia specific cytotoxic T lymphocytes (CTLs). METHODS: C57BL/6 mice were induced to lymphopenia with 6 Gy total body irradiation. Spleen T cells or leukemia specific T cells from EGFP+ transgenic C57BL/6-EGFP mice were adoptively transferred by intravenous injection. The mice were challenged subcutaneously with 1 x 10(6) FBL3 leukemic cells at day 2 after irradiation. The peripheral WBC count, percentage of EGFP+ cells, subsets of T cells and tumor sizes were monitored. RESULT: Both of the spleen T cell and leukemia specific CTL proliferated efficiently with the percentage of EGFP+ cells of 28. 81% and 42.24%, respectively, after infused into lymphopenic recipients. However, spleen T cells had no anti-leukemia effect regardless of its expansion. In contrast, leukemia specific CTLs showed a more rapid and extensive expansion under the condition of lymphopenia and a enhanced anti-leukemia immunity. CONCLUSION: Transfusion of leukemia specific CTLs under lymphopenia state could be a feasible strategy to expand leukemia specific CTLs and generate favorable anti-leukemia effect in vivo.

[Establishment of a mouse model for detecting multi-drug resistant minimal residual leukemia cells expressing green fluorescent protein].

This study aimed to investigate the pathophysiology and therapy of multi-drug resistant model of minimal residual leukemia in mice. The multi-drug resistant model of minimal residual leukemia was established by using P388/VCR-G cell line expressing enhanced green fluorescent protein (EGFP) and DBA mice. The results showed that P388/VCR-G were inoculated in the abdominal cavities of DBA mice, the incidence of leukemia was 100%. Any of these mice with leukemia could not obtain remission spontaneously. The model of leukemia was sensitive to cyclophosphamide (Cy) and the time of survival was related to the dose of Cy received. The logarithm of cells inoculated in mice correlated regressionally with the dose of Cy. So this model was ideal for research on minimal residual leukemia. The distribution of residual leukemia cells in complete remission was not uniform in different organs including liver, spleen, thymus and bone marrow. Minimal residual leukemia cells could be found by fluorescent microscopy in freezing tissue slice. It is concluded that the multi-drug resistant model of minimal residual leukemia expressing EGFP can be established by using P388/VCR-G cell line and DBA mice. The minimal residual leukemia cells can be observed by fluorescence microscopy in complete remission stage.