Kung Chao Chang

Intramyocardial Peptide Nanofiber Injection Improves Postinfarction Ventricular Remodeling and Efficacy of Bone Marrow Cell Therapy in Pigs

Background— Growing evidence suggests that intramyocardial biomaterial injection improves cardiac functions after myocardial infarction (MI) in rodents. Cell therapy is another promising approach to treat MI, although poor retention of transplanted cells is a major challenge. In this study, we hypothesized that intramyocardial injection of self-assembling peptide nanofibers (NFs) thickens the infarcted myocardium and increases transplanted autologous bone marrow mononuclear cell (MNC) retention to attenuate cardiac remodeling and dysfunction in a pig MI model. Methods and Results— A total of 40 mature minipigs were divided into 5 groups: sham, MI+normal saline, MI+NFs, MI+MNCs, and MI+MNCs/NFs. MI was induced by coronary occlusion followed by intramyocardial injection of 2 mL normal saline or 1% NFs with or without 1×108 isolated autologous MNCs. NF injection significantly improved diastolic function and reduced ventricular remodeling 28 days after treatment. Injection of MNCs alone ameliorated systolic function only, whereas injection of MNCs with NFs significantly improved both systolic and diastolic functions as indicated by +dP/dt and −dP/dt (1214.5±91.9 and −1109.7±91.2 mm Hg/s in MI+NS, 1693.7±84.7 and −1809.6±264.3 mm Hg/s in MI+MNCs/NFs, respectively), increased transplanted cell retention (29.3±4.5 cells/mm2 in MI+MNCs and 229.4±41.4 cells/mm2 in MI+MNCs/NFs) and promoted capillary density in the peri-infarct area. Conclusions— We demonstrated that NF injection alone prevents ventricular remodeling, whereas cell implantation with NFs improves cell retention and cardiac functions after MI in pigs. This unprecedented combined treatment in a large animal model has therapeutic effects, which can be translated to clinical applications in the foreseeable future.

Comparison of the expression and prognostic significance of differentiation markers between diffuse large B-cell lymphoma of central nervous system origin and peripheral nodal origin.

PURPOSE: Whether diffuse large B-cell lymphoma (DLBCL) of primary central nervous system origin (PCNSL) is biologically different from DLBCL of peripheral nodal origin (NL) remains unclear. The purpose of this study was to compare the expression frequencies and prognostic significance of a panel of cell differentiation markers between these two disease entities. EXPERIMENTAL DESIGN: This study included HIV-unrelated patients with PCNSL (n = 51) and NL (n = 72) treated at four hospitals in Taiwan for whom archival tumor tissue was available. Immunohistochemistry for CD10, BCL-6, MUM-1, vs38c, CD138, and BCL-2 was done. CD10, BCL-6, and MUM-1 expression results were used to classify all cases into the germinal center B-cell (GCB) or the non-GCB subgroup. The prognostic significances of clinical and immunophenotypic markers were evaluated. RESULTS: Nuclear MUM-1 expression was significantly higher in PCNSL than in NL (P < 0.001; 84% versus 53%). PCNSL tumors were more frequently classified into the non-GCB subgroup than NL tumors (P = 0.020; 78% versus 62%). For patients with PCNSL, univariate analysis showed that patients with BCL-6 expression had a trend towards longer survival (P = 0.073; median survival, 25.3 versus 7.3 months), and multivariate analysis showed BCL-6 was an independent prognostic factor (P = 0.026). For patients with NL, both of univariate (P = 0.003) and multivariate analyses (P = 0.002) showed that GCB was significantly associated with favorable survival. CONCLUSION: The higher frequency of non-GCB subclassification, which was mainly contributed by nuclear MUM-1 expression in PCNSL implies that it has a more differentiated cellular origin than NL. BCL-6 expression in patients with PCNSL and GCB subgroup in patients with NL were favorable prognostic factors.

Increase of programmed death-1-expressing intratumoral CD8 T cells predicts a poor prognosis for nasopharyngeal carcinoma

Intratumoral cytotoxic T lymphocytes are critical for controlling tumor recurrence, and programmed death-1 (PD-1) is a recognized marker of T-cell dysfunction. We analyzed this marker and its binding ligands in nasopharyngeal tumor tissue and non-cancerous nasopharyngeal control tissue to retrospectively evaluate the correlation between its expression and the post-treatment outcome of nasopharyngeal carcinoma patients. Using double immunofluorescence staining, we found that the expression of PD-1 in CD8 T cells in tumor tissue was significantly higher than in control tissue (mean: 28.4 vs 3.9%, P<0.0001). Although the expression rate of PD-1 in intratumoral CD8 cells was not associated with the other clinicopathological parameters examined, the higher expression rate in this subset of T cells significantly correlated with a poorer prognosis of overall survival, disease-free survival, and locoregional recurrence-free survival of the cancer patients (P=0.05, 0.007, and 0.004, respectively). Multivariate analysis confirmed it as an independent risk factor for death, treatment failure, and local recurrence of nasopharyngeal carcinoma. On the other hand, the expression of PD-1 in CD4 T cells and of its ligands in epithelial and stromal cells was not significantly different between tumor and control tissue, and its expression was not associated with clinical outcome of the cancer patients. We propose that PD-1 expression in CD8 cells reflects the selective suppression of cytotoxic lymphocytes in the tumor microenvironment and predicts recurrence of nasopharyngeal carcinoma after conventional therapies.

Lymphocyte and antibody responses reduce enterovirus 71 lethality in mice by decreasing tissue viral loads

ABSTRACT Enterovirus 71 (EV71) infects the central nervous system and causes death and long-term neurological sequelae in hundreds of thousands of young children, but its pathogenesis remains elusive. Immunopathological mechanisms have been suspected to contribute to the pathogenesis of neurological symptoms, so anti-inflammatory agents have been used to treat patients with neurological symptoms. The present study was therefore designed to investigate the functions of lymphocyte and antibody responses in EV71 infection using a mouse model. Immunohistochemical staining analysis revealed virus and three types of lymphocytes, B cells, CD4 T cells, and CD8 T cells, in the spinal cord of an EV71-infected patient who died. A study of mice showed that the levels of virus and lymphocytes in brains and antibody titers in sera were elevated during the time when the mice succumbed to death in a phenomenon analogous to that observed in patients. Further studies demonstrated that after infection, the disease severity, mortality, and tissue viral loads of mice deficient in B, CD4 T, or CD8 T cells were significantly higher than those of wild-type mice. In addition, treatment with a virus-specific antibody, but not a control antibody, before or after infection significantly reduced the disease severity, mortality, and tissue viral loads of mice deficient in B cells. Our results show that both lymphocyte and antibody responses protect mice from EV71 infection. Our study suggests the use of vaccines and virus-specific antibodies to control fatal outbreaks and raises caution over the use of corticosteroids to treat EV71-infected patients with neurological symptoms.

miR-320 regulates tumor angiogenesis driven by vascular endothelial cells in oral cancer by silencing neuropilin 1

Tumor angiogenesis is a critical process during cancer progression that modulates tumor growth and metastasis. Here, we identified an anti-angiogenic microRNA, miR-320, which is decreased in oral squamous cell carcinoma (OSCC) cell lines and tumor tissues from OSCC patients, down-regulated in blood vessels and inversely correlated with vascularity in OSCC tissues. Neuropilin 1 (NRP1), an important regulator of angiogenesis, was found to be a target of miR-320. The 3′-untranslated region of NRP1 mRNA contains multiple miR-320 binding sites, and its expression was regulated by miR-320. By administering either miR-320 precursor or antagonist, we found that miR-320 suppressed the migration, adhesion and tube formation of vascular endothelial cells. Knockdown of NRP1 abolished antagomiR-320-induced cell migration. Additionally, miR-320 expression was regulated by hypoxia in growth factor-deficient conditions by the hypoxia-inducible factor 1-alpha. Furthermore, lentivirus carrying the miR-320 precursor suppressed the tumorigenicity of OSCC cells and tumor angiogenesis in vivo. Taken together, these data show that miR-320 regulates the function of vascular endothelial cells by targeting NRP1 and has the potential to be developed as an anti-angiogenic or anti-cancer drug.

Distribution Patterns of Dendritic Cells and T Cells in Diffuse Large B-Cell Lymphomas Correlate with Prognoses

Purpose: Diffuse large B-cell lymphoma (DLBCL), the most common subtype of non-Hodgkins lymphomas, accounts for 30% to 40% of all lymphoma cases. However, long-term survival by current chemotherapy was achieved in only 40% of patients, warranting the development of novel therapeutic strategies including T-cell immunotherapy. However, the level of baseline immune activation in DLBCL is unclear. Experimental Design: The density and distribution of dendritic cells and T cells in 48 cases of primary DLBCL was evaluated by immunohistochemistry. Results: Increased numbers of intratumoral CD1a+ dendritic cells and increased S100+ cells and CD45RO+ T cells around the edges of the tumors were seen in 10 of 48 (21%), 9 of 48 (19%), and 10 of 48 (21%) cases and these were correlated with a favorable prognosis (P = 0.015; P = 0.070, and P = 0.017, respectively), along with increased granzyme B+ T cells in tumor beds (P = 0.013). Increased peritumoral T cells were correlated with tumor expression of HLA-DR (r = 0.446; P = 0.002). Extranodal lymphomas showed fewer tumor-associated CD45RO+ T cells (r = −0.407; P = 0.001) and less conspicuous dendritic cell infiltrates. Conclusions: In DLBCL, the presence of baseline antitumor immune response is associated with favorable clinical outcome, and thus adjuvant T-cell immunotherapy may further boost treatment responses.

Follicular dendritic cell sarcoma of the colon mimicking stromal tumour

Follicular dendritic cell tumours are very rare neoplasms that often occur in lymph nodes. We report here a case in the colon, a hitherto unreported site, in a 37‐year‐old female. The differentiation from gastrointestinal stromal tumour is emphasized.

Epstein-Barr Virus Latent Membrane Protein 2A Promotes Invasion of Nasopharyngeal Carcinoma Cells through ERK/Fra-1-Mediated Induction of Matrix Metalloproteinase 9

ABSTRACT Epstein-Barr virus (EBV)-associated nasopharyngeal carcinoma (NPC) is highly metastatic, and this malignant feature may be promoted by an EBV oncoprotein, latent membrane protein 2A (LMP2A). Acting as a signal regulator, LMP2A can enhance invasiveness and motility of epithelial cells. Downstream from the LMP2A-triggered signaling events, it is largely unknown what key effector proteins are induced and essentially promote cell invasion. In the present study, we found that in NPC cells, LMP2A upregulated matrix metalloproteinase 9 (MMP9), a metastasis-associated protease. LMP2A increased MMP9 expression at both the mRNA and protein levels. It also activated the MMP9 promoter, in which two AP-1 elements were required for the promoter activation. Among AP-1 transcription factors, Fra-1 was induced by LMP2A and is essential for LMP2A-triggered MMP9 expression. Induction of Fra-1 was dependent on the LMP2A-activated ERK1/2 pathway, and induction of the ERK1/2–Fra-1–MMP9 axis required PY motifs in the amino-terminal domain of LMP2A. Notably, LMP2A-promoted invasion of NPC cells was blocked when MMP9 expression, Fra-1 induction, or ERK1/2 activation was inhibited. In addition, we found an association of LMP2A with MMP9 expression in NPC tumor biopsy specimens, where Fra-1 was a major mediation factor. This study reveals an underlying mechanism of LMP2A-induced cell invasion, from signal transduction to upregulation of a critical protease. Considering that MMP9 can also be upregulated by another EBV oncoprotein, LMP1, this protease may be a pivotal effector at which the EBV-induced, invasion-promoting mechanisms converge, serving as an attractive therapeutic target for NPC treatment.

Endoplasmic reticulum stress triggers XBP-1-mediated up-regulation of an EBV oncoprotein in nasopharyngeal carcinoma

Endoplasmic reticulum (ER) stress-activated unfolded protein response (UPR) plays multiple roles in cancer development, but its specific roles for virus-associated cancers have not been fully understood. It is still unknown whether ER stress/UPR occurs in and contributes to nasopharyngeal carcinoma (NPC), an epithelial malignancy closely associated with EBV. Here, we report that UPR proteins are frequently detected in NPC biopsies. In addition, we reveal that, in EBV-infected NPC cells, ER stress inducers up-regulate a potent EBV oncoprotein latent membrane protein 1 (LMP1), and the ER stress-induced LMP1 enhances production of interleukin-8. ER stress triggers LMP1 expression at a transcriptional level, activating a distal LMP1 promoter TR-L1. TR-L1 contains an ER stress-responsive element, which is targeted by an UPR protein XBP-1. Ectopic expression of XBP-1 induces LMP1 expression, and knockdown of XBP-1 blocks ER stress-triggered up-regulation of LMP1 in NPC cells. Furthermore, XBP-1 significantly correlates with LMP1 expression in NPC tumor biopsies. Therefore, this study not only provides a novel clue linking ER stress/UPR to EBV-associated NPC but also suggests that ER stress/UPR can promote virus-associated cancer in a unique way by driving expression of a viral oncogene.

MicroRNA-18a is elevated in prostate cancer and promotes tumorigenesis through suppressing STK4 in vitro and in vivo

MicroRNAs (miRNAs) comprise a class of short, non-coding RNAs that regulate protein synthesis through posttranscriptional modifications. In this study, we found significant upregulation of miR-18a in prostate cancer specimens and prostate cancer cell lines compared with the normal controls. MiRNAs can be separated into two groups based on whether they regulate tumor suppressors or oncogenes. In our previous study, we found that miR-18a, which belongs to the miR17-92 cluster, is upregulated in prostate cancer; the objective of this study was to investigate the associated regulatory mechanisms. We found that miR-18a is upregulated in clinical tumor specimens and cancer cell lines. Our bioinformatics analysis showed that the serine/threonine-protein kinase 4 (STK4) 3′ untranslated region contains a highly conserved binding site for the miR-18a seed region. Luciferase reporter assays were performed to indicate that STK4 is a direct target of miR-18a. Interestingly, miR-18a knockdown decreased cell growth in prostate cancer cells and significantly decreased prostate tumor growth in in vivo nude mice experiments through STK4-mediated dephosphorylation of AKT and thereby inducing apoptosis. Our results suggest that miR-18a acts as an oncomiR targeting STK4 in prostate cancer, and inhibition of miR-18a expression may offer therapeutically beneficial option for prostate cancer treatment.