Tumor-associated microglia/macrophages enhance the invasion of glioma stem-like cells via TGF-ß1 signaling pathway.

The invasion of malignant glioma cells into the surrounding normal brain tissues is crucial for causing the poor outcome of this tumor type. Recent studies suggest that glioma stem-like cells (GSLCs) mediate tumor invasion. However, it is not clear whether microenvironment factors, such as tumor-associated microglia/macrophages (TAM/Ms), also play important roles in promoting GSLC invasion. In this study, we found that in primary human gliomas and orthotopical transplanted syngeneic glioma, the number of TAM/Ms at the invasive front was correlated with the presence of CD133(+) GSLCs, and these TAM/Ms produced high levels of TGF-ß1. CD133(+) GSLCs isolated from murine transplanted gliomas exhibited higher invasive potential after being cocultured with TAM/Ms, and the invasiveness was inhibited by neutralization of TGF-ß1. We also found that human glioma-derived CD133(+) GSLCs became more invasive upon treatment with TGF-ß1. In addition, compared with CD133(-) committed tumor cells, CD133(+) GSLCs expressed higher levels of type II TGF-ß receptor (TGFBR2) mRNA and protein, and downregulation of TGFBR2 with short hairpin RNA inhibited the invasiveness of GSLCs. Mechanism studies revealed that TGF-ß1 released by TAM/Ms promoted the expression of MMP-9 by GSLCs, and TGFBR2 knockdown reduced the invasiveness of these cells in vivo. These results demonstrate that TAM/Ms enhance the invasiveness of CD133(+) GSLCs via the release of TGF-ß1, which increases the production of MMP-9 by GSLCs. Therefore, the TGF-ß1 signaling pathway is a potential therapeutic target for limiting the invasiveness of GSLCs.

[Signal Patterns of Dual Color Dual Fusion Fluorescence in Situ Hybridization for Detection of Genetic Abnormality in Adult Patients with ALL and Their Clinical Application].

OBJECTIVE: To study the signal patterns of dual color dual fusion fluorescence in situ hybridization (DCDF-FISH) for detection of genetic abnormality in adult acute lymphoblastic leukemia (ALL) patients and their diagnostic value and clinical application. METHODS: The clinical data of 68 ALL patients confirmed in our hospital were analyzed retrospectively; The bone marrow samples were detected by DCDF-FISH, flow cytometry, conventional cytogenetics (CCG), reverse transcriptase polymerase chain reaction (RT-PCR), and the correlation of these results was compared. And the reaction of patients to treatment was dynamically observed by DCDF-FISH. RESULTS: Sixteen signal patterns were found in DCDF-FISH, including 14 kinds of atypical signal patterns (signal patterns of 1R2G, 2R3G, 2R4G and 3R3G as abnormal signal patterns without BCR/ABL fusion gene. Signal patterns of 1R1G1F, 1R1G3F, 1R1G4F, 1R2G1F, 1R2G2F, 1R2G3F, 1RnG2F (n ≥ 3), 2R2G1F, 1G4F, 1R4F corresponded to t (9;22) karyotype). Ph(+) ALL patients accounted for 17. All cases with Ph chromosome or BCR/ABL positive were B-ALL or My(+)-B-ALL. The Ph chromosome was detected in 12 cases (positive rate was 18%) by CCG. The positive rate was 25% (17/68) by DCDF-FISH and RT-PCR. The DCDF-FISH fluorescence pattern change before and after chemotherapy of the patients showed that the quantity and form of the signal pattern was changed after chemotherapy, and the common characteristics was the Ph chromosome in patients. CONCLUSION: The DCDF-FISH is a sensitive and reliable method for the detection of BCR/ABL rearrangement. Analyzing the dynamical change of DCDF-FISH signal patterns has been comfirmed to have a important guiding significance in the diagnosis, and anlysis of response to therapy, drug resistance and the prognosis of ALL patients.

POU5F1 enhances the invasiveness of cancer stem-like cells in lung adenocarcinoma by upregulation of MMP-2 expression.

Lung cancer is the leading cause of cancer-related human deaths. Exploration of the mechanisms underlying the metastasis of cancer stem-like cells (CSLCs) will open new avenues in lung cancer diagnosis and therapy. Here, we demonstrated that CSLCs-derived from lung adenocarcinoma (LAC) cells displayed highly invasive and migratory capabilities via expressing high levels of POU5F1 and MMP-2. We found that POU5F1 directly regulated MMP-2 transcription via interaction with the promoter of MMP-2. POU5F1 knockdown in LACSLCs reduced MMP-2 protein abundance, leading to inhibition of the cell invasion, migration and tumorigenesis potentials of LAC cells. Clinically, aberrantly high expressions of POU5F1 and MMP-2 were inversely correlated with the survival of LAC patients, and the double-positive POU5F1 and MMP-2 showed the worst prediction for the patient's poor survival. These results indicate that POU5F1 can bind to the MMP-2 promoter for the degradation of surrounding extracellular matrix, and therefore promote invasive and migratory capabilities of LACSLCs. Moreover, our data implicate that the pathological detection of the double-positive expressions for POU5F1 and MMP-2 will be useful as diagnostic and prognostic biomarkers in LAC to advance anti-metastasis therapy.

TGF-ß1 enhances tumor-induced angiogenesis via JNK pathway and macrophage infiltration in an improved zebrafish embryo/xenograft glioma model.

Angiogenesis plays a crucial role at the early stage of tumorigenesis and tumor progression. A suitable model will be useful not only for the clarification of the underlying molecular mechanisms, but also for high-throughput identification of novel anti-angiogenesis compounds. Here, we established a zebrafish model for the purpose to investigate angiogenesis and screen anti-angiogenic compounds. Glioma U87 cells expressing red fluorescent protein (RFP) were transplanted in fli:GFP transgenic zebrafish embryos where significant angiogenesis was observed. TGF-ß1 enhanced glioma-induced angiogenesis, which was inhibited by JNK inhibitor SP600125 but not p38 MAPK inhibitor SB202190, ERK inhibitor PD98059, or PI3K inhibitor LY294002, indicating the important role of TGF-ß1 and JNK pathways in this process. Moreover, the glioma-induced angiogenesis was associated with macrophage infiltration that was further enhanced by TGF-ß1. Therefore, our zebrafish model provides a powerful in vivo tool for the investigation of tumor-induced angiogenesis, and a cost-effective system for high-throughput screening of anti-angiogenic compounds.