Min Tu

Publications (4)14.54 Total impact

• Article: Generation and characterization of rabbit polyclonal antibodies against Vasohibin-2 for determination of its intracellular localization.

  Jie Sun, Min Tu, Bei Han, Xiaofeng Xue, Ye Zhang, Jishu Wei, Jianmin Chen, Zipeng Lu, Yong An, Baobao Cai, Nan Lv, Kuirong Jiang, Yi Miao, Wentao Gao
  [show abstract] [hide abstract]
  ABSTRACT: Vasohibin-2 was recently identified as an important pro-angiogenesis factor in solid tumor and intracellular localization of its variants is important for elucidating the downstream mechanism(s) of its effects. Currently there are no reported antibodies affordable for intracellular localization. The aim of this study was to generate and characterize polyclonal antibodies against Vasohibin-2 and to determine the intracellular localization of Vasohibin-2. In this study, two polypeptides were synthesized and one prokaryotic Vasohibin-2 recombinant protein was custom-made. New Zealand rabbits were immunized with the polypeptide mixture and prokaryotic recombinant protein, respectively. The purified antibodies from the antiserum were validated by ELISA, western blotting (WB), immunofluorescence (IF), immunohistochemistry (IHC) and immunoprecipitation (IP). In order to determine intracellular localization, the cytoplasmic and nuclear proteins of the human liver cancer cell line HepG2 were isolated for the detection of Vasohibin-2 by western blotting. Vasohibin-2 cDNA, coding for 311 and 355 amino acid residues, fused with or without a DDK/V5 tag at the c-terminus, respectively, was cloned into the Lv-CMV-EGFP vector. Lentiviruses were successfully packaged. Vasohibin-2-overexpressing HepG2-VASH2 (355 amino acid residues) and HepG2-VASH2-V5 (311 amino acid residues fused with V5 tag at the c-terminus) human liver cancer cell lines were established. Approximately 1-2x106 HepG2, HepG2-VASH2 and HepG2-VASH2-V5 cells were injected subcutaneously into the flanks of BALB/c nude mice. Xenograft tumors were harvested for immunohistochemistry. HepG2 cells were transiently transfected with the Lv-CMV-EGFP vectors containing Vasohibin-2 cDNA (coding for 311/355 amino acid residues with a DDK tag at the c-terminal), followed by anti-DDK immunofluorescence. The antibodies obtained were able to detect human VASH2 successfully as applied in western blotting, IF, IHC and IP. Results from IF, IHC and WB (post cytoplasmic/nuclear protein isolation) showed a quite different intracellular localization of VASH2 protein. The VASH2 (with 355 amino acid residues) was located in the cytoplasm while VASH2 (with 311 amino acid residues) was located in the nucleus. The former was found to be a relatively low abundance protein. We successfully generated three rabbit anti-human Vasohibin-2 polyclonal antibodies which can be used for western blotting, IF, IP and IHC. These antibodies will provide a convenient tool for further studies on Vasohibin-2. This is the first study to report differences in the intracellular localization of the VASH2 protein and, hence, a new research direction on the study of VASH2.
  International Journal of Oncology 04/2013; · 2.40 Impact Factor
• Article: miRNA-181b increases the sensitivity of pancreatic ductal adenocarcinoma cells to gemcitabine in vitro and in nude mice by targeting BCL-2.

  Baobao Cai, Yong An, Nan Lv, Jianmin Chen, Min Tu, Jie Sun, Pengfei Wu, Jishu Wei, Kuirong Jiang, Yi Miao
  [show abstract] [hide abstract]
  ABSTRACT: Pancreatic ductal adenocarcinoma (PDAC) is a highly lethal disease and is usually resistant to chemotherapy. MicroRNA‑181b (miR-181b) has been reported to be associated with chemoresistance in various types of cancer. In this study, we investigated the effects of miR-181b on the chemosensitivity of PDAC cells to gemcitabine and the underlying molecular events. miR-181b mimics and inhibitors were synthesized for transient gene transfection in vitro. Lentivirus carrying miR-181b mimics were used to infect PDAC cells for nude mouse xenograft assays by implanting infected PDAC cells into recipient mice. Cell viability was determined by MTT assays, while gene expression was assessed using qRT-PCR, western blot analysis and enzyme-linked immunosorbent assay (ELISA). miR-181b targeting BCL-2 expression was assessed by a dual-luciferase activity assay. The data showed that miRNA-181b expression sensitized PDAC cells to gemcitabine treatment. Although gemcitabine-resistant PDAC cell sublines (SW1990/GR and CFPAC-1/GR) expressed higher levels of miRNA-181b, gemcitabine induced higher levels of apoptosis in PDAC cells transfected with miRNA-181b mimics. The nude mouse xenograft assay data showed that miR-181b transfection also sensitized the cells to gemcitabine treatment in vivo. Molecularly, bioinformatics data predicted that miR-181b was able to bind to BCL-2 mRNA 3'UTR. The dual luciferase activity assay revealed that miRNA-181b downregulated BCL-2 expression. The results from western blot analysis showed a reduced BCL-2 expression following miR-181b transfection but an enhanced caspase-3 activity in miRNA-181b mimic-transfected PDAC cells. This study demonstrates that miRNA-181b sensitizes PDAC cells to gemcitabine by targeting BCL-2.
  Oncology Reports 02/2013; · 1.84 Impact Factor
• Article: MAP3K10 promotes the proliferation and decreases the sensitivity of pancreatic cancer cells to gemcitabine by upregulating Gli-1 and Gli-2.

  Yong An, Baobao Cai, Jianmin Chen, Nan Lv, Jie Yao, Xiaofeng Xue, Min Tu, Dong Tang, Jishu Wei, Kuirong Jiang, Junli Wu, Qiang Li, Wentao Gao, Yi Miao
  [show abstract] [hide abstract]
  ABSTRACT: Pancreatic ductal adenocarcinoma (PDAC) is among the most lethal human malignancies and is regulated by Sonic Hedgehog (Shh) signaling. Recently, MAP3K10 has been shown to regulate Shh signaling, suggesting a role for MAP3K10 in the tumorigenesis of PDAC. We determined the expression status of MAP3K10 in PDAC tissues and cell lines, and analyzed the viability and cell proliferation of PDAC cells with an overexpression or knockdown of MAP3K10 in vitro. MAP3K10 was upregulated in PDAC tissues and cell lines. Overexpression of MAP3K10 promoted the proliferation and decreased the gemcitabine sensitivity of pancreatic cancer cells. In contrast, knockdown of MAP3K10 significantly decreased cell proliferation and sensitized cells to gemcitabine. However, neither overexpression nor knockdown of MAP3K10 affected cell migration. Moreover, overexpression of MAP3K10 resulted in upregulation of Gli-1 and Gli-2 in PDAC cells. Our results indicate a novel and important role for MAP3K10 in the proliferation and chemoresistance of PDAC. Our study suggests that targeting MAP3K10 is a potential strategy for the development of alternative therapies for pancreatic cancers.
  Cancer letters 11/2012; · 4.86 Impact Factor
• Article: Persistent activation of pancreatic stellate cells creates a microenvironment favorable for the malignant behavior of pancreatic ductal adenocarcinoma.

  Dong Tang, Daorong Wang, Zhongxu Yuan, Xiaofeng Xue, Ye Zhang, Yong An, Jianmin Chen, Min Tu, Zipeng Lu, Jishu Wei, Kuirong Jiang, Yi Miao
  [show abstract] [hide abstract]
  ABSTRACT: Pancreatic ductal adenocarcinoma (PDAC) is one of the most common malignant tumors with poor prognosis due to extremely high malignancy, low rate of eligibility for surgical resection and chemoradiation resistance. Increasing evidence indicate that the interaction between activated pancreatic stellate cells (PSCs) and PDAC cells plays an important role in the development of PDAC. By producing high levels of cytokines, chemotactic factors, growth factors and excessive extracellular matrix (ECM), PSCs create desmoplasia and a hypoxic microenvironment that promote the initiation, development, evasion of immune surveillance, invasion, metastasis and resistance to chemoradiation of PDAC. Therefore, targeting the interaction between PSCs and PDAC cells may represent a novel therapeutic approach to advanced PDAC, especially therapies that target PSCs of the pancreatic tumor microenvironment.
  International Journal of Cancer 07/2012; · 5.44 Impact Factor