Collagen stabilization through irreversible cross‐linking is thought to promote hepatic fibrosis progression and limit its reversibility. However, the mechanism of this process remains poorly ...defined. We studied the functional contribution of lysyl oxidase (LOX) to collagen stabilization and hepatic fibrosis progression/reversal in vivo using chronic administration of irreversible LOX inhibitor β‐aminopropionitrile (BAPN, or vehicle as control) in C57Bl/6J mice with carbon tetrachloride (CCl4)‐induced fibrosis. Fibrotic matrix stability was directly assessed using a stepwise collagen extraction assay and fibrotic septae morphometry. Liver cells and fibrosis were studied by histologic, biochemical methods and quantitative real‐time reverse‐transcription PCR. During fibrosis progression, BAPN administration suppressed accumulation of cross‐linked collagens, and fibrotic septae showed widening and collagen fibrils splitting, reminiscent of remodeling signs observed during fibrosis reversal. LOX inhibition attenuated hepatic stellate cell activation markers and promoted F4/80‐positive scar‐associated macrophage infiltration without an increase in liver injury. In reversal experiments, BAPN‐treated fibrotic mice demonstrated accelerated fibrosis reversal after CCl4 withdrawal. Our findings demonstrate for the first time that LOX contributes significantly to collagen stabilization in liver fibrosis, promotes fibrogenic activation of attenuated hepatic stellate cells, and limits fibrosis reversal. Our data support the concept of pharmacologic targeting of LOX pathway to inhibit liver fibrosis and promote its resolution.—Liu, S. B., Ikenaga, N., Peng, Z.‐W., Sverdlov, D. Y., Greenstein, A., Smith, V., Schuppan, D., Popov, Y. Lysyl oxidase activity contributes to collagen stabilization during liver fibrosis progression and limits spontaneous fibrosis reversal in mice. FASEB J. 30, 1599–1609 (2016). www.fasebj.org
Pancreatic stellate cells (PSC), which are implicated in desmoplasia in pancreatic cancer, enhance the malignancy of cancer cells and confer resistance to established treatments. We investigated ...whether the antifibrotic agent pirfenidone can suppress desmoplasia and exert antitumor effects against pancreatic cancer. Primary PSCs were established from pancreatic cancer tissue obtained during surgery. In vitro, pirfenidone inhibited the proliferation, invasiveness, and migration of PSCs in a dose-dependent manner. Although supernatants of untreated PSCs increased the proliferation, invasiveness, and migration of pancreatic cancer cells (PCC), supernatants of pirfenidone-treated PSCs decreased these effects. Exposure to PCC supernatant increased the production of platelet-derived growth factor-A, hepatic growth factor, collagen type I, fibronectin, and periostin in PSCs, which was significantly reduced by pirfenidone. Mice were subcutaneously implanted with PCCs (SUIT-2 cells) and PSCs into the right flank and PCCs alone into the left flank. Oral administration of pirfenidone to these mice significantly reduced tumor growth of co-implanted PCCs and PSCs, but not of PCCs alone. Pirfenidone also decreased the proliferation of PSCs and the deposition of collagen type I and periostin in tumors. In mice with orthotopic tumors consisting of PCCs co-implanted with PSCs, pirfenidone suppressed tumor growth, reduced the number of peritoneal disseminated nodules, and reduced the incidence of liver metastasis. Pirfenidone in combination with gemcitabine more effectively suppressed orthotopic tumor growth compared with pirfenidone or gemcitabine alone. In conclusion, our findings indicate that pirfenidone is a promising antitumor agent for pancreatic cancer, owing to its suppression of desmoplasia through regulating PSCs.
Radiofrequency ablation (RFA) is a potentially curative therapy for hepatocellular carcinoma (HCC). However, incomplete RFA can induce accelerated invasive growth at the periphery. The mechanisms ...underlying the RFA‐induced tumor promotion remain largely unexplored. Three human HCC cell lines were exposed to 45°C‐55°C for 10 minutes, simulating the marginal zone of RFA treatment. At 5‐12 days post‐treatment cell proliferation, parameters of epithelial‐mesenchymal transition (EMT), and activation of mitogen‐activated protein kinases were analyzed. Livers from patients with viral hepatitis without and with HCC (n = 114) were examined to confirm the relevance of altered kinase patterns. In vivo tumorigenic potential of heat‐treated versus untreated HCC cells was studied in nude mice. Heating to 55°C killed all HCC cells, whereas 65%‐85% of cells survived 48°C‐50°C, developing spindle‐like morphology and expressing CD133, cytokeratin (CK)7, CK19, procollagen‐α1(I), and Snail at day 5 after heat exposure, which returned to baseline at day 12. Heat‐exposed HCC cells showed enhanced proliferation and prominent activation of p46‐Shc (Src homology and collagen) and downstream extracellular signal‐related kinase (Erk)1/2. In patients, Shc expression correlated with malignant potential and overall survival. Blocking Erk1/2 reduced proliferation and EMT‐like changes of heat‐treated HCC cells. Implantation of heat‐exposed HEPG2 cells into nude mice induced significantly larger, more aggressive tumors than untreated cells. Conclusions: Sublethal heat treatment skews HCC cells toward EMT and transforms them to a progenitor‐like, highly proliferative cellular phenotype in vitro and in vivo, which is driven significantly by p46Shc‐Erk1/2. Suboptimal RFA accelerates HCC growth and spread by transiently inducing an EMT‐like, more aggressive cellular phenotype. (Hepatology 2013;58:1667–1680)
Background
Gastric cancer (GC) is characterized by an immunosuppressive and treatment-resistant tumor immune microenvironment (TIME). Here, we investigated the roles of different immunosuppressive ...cell types in the development of the GC TIME.
Methods
Single-cell RNA sequencing (scRNA-seq) and multiplex immunostaining of samples from untreated or immune checkpoint inhibitor (ICI)-resistant GC patients were used to examine the correlation between certain immunosuppressive cells and the prognosis of GC patients.
Results
The results of the scRNA-seq analysis revealed that tumor-infiltrating monocytic myeloid-derived suppressor cells (TI-M-MDSCs) expressed higher levels of genes with immunosuppressive functions than other immunosuppressive cell types. Additionally, M-MDSCs in GC tissues expressed significantly higher levels of these markers than adjacent normal tissues. The M-MDSCs were most enriched in GC tissues relative to adjacent normal tissues. Among the immunosuppressive cell types assessed, the M-MDSCs were most enriched in GC tissues relative to adjacent normal tissues; moreover, their presence was most strongly associated with a poor prognosis. Immediate early response 3 (
IER3
), which we identified as a differentially expressed
g
ene between M-MDSCs of GC and adjacent normal tissues, was an independent poor prognostic factor in GC patients (
P
= 0.0003). IER3
+
M-MDSCs expressed higher levels of genes with immunosuppressive functions than IER3
−
M-MDSCs and were abundant in treatment-resistant GC patients.
Conclusions
The present study suggests that TI-M-MDSCs, especially IER3
+
ones, may play a predominant role in the development of the immunosuppressive and ICI-resistant GC TIME.
Oxygen-deficient titania (TiO2) nanoparticle photocatalysts were synthesized using a flame synthesis method. The degree of oxygen deficiency in the TiO2 particles could be changed by moving the ...position of the quenching N2 gas ring with respect to the flame to reduce the oxygen concentration in the flame. Photocatalytic property evaluation revealed that the produced TiO2 particles had better photocatalytic performance in the visible light region (wavelength λ > 420 nm) than commercially available P25 TiO2 particles. We also found that high crystallinity and moderate oxygen deficiency are required for improved photocatalytic performance.
Background & Aims Pancreatic stellate cells (PSCs) promote the progression of pancreatic cancer by producing extracellular matrix and soluble factors. However, the functional heterogeneity of PSCs ...has not been identified until now. Detailed characterization of the PSCs in human pancreatic cancer would provide a set of potential targets for stroma-directed therapy. Methods We isolated PSCs from fresh pancreatic ductal adenocarcinoma tissue and sorted them by flow cytometry according to cell surface expression of CD10, which is a stromal prognostic marker for various tumors. We analyzed the functional differences between CD10+ PSCs and CD10− PSCs. Results Immunohistochemical analysis showed that the frequency of CD10 expression by PSCs was markedly higher in tumor tissue than in normal tissue (33.7% vs 0%, respectively, P = .028). In pancreatic ductal adenocarcinoma, CD10 expression by PSCs was associated with positive nodal metastases ( P = .011) and a shorter survival time ( P < .001). In vitro coculture experiments showed that CD10+ PSCs promoted the invasiveness of pancreatic cancer cell lines, SUIT-2 and Panc-1 cells more intensively than CD10− PSCs. CD10+ PSCs significantly increased the tumor growth and invasiveness of SUIT-2 cells in a murine cotransplantation model. CD10+ PSCs secreted higher levels of matrix metalloproteinase 3 than CD10− PSCs, and knockdown of matrix metalloproteinase 3 in cocultured PSCs reduced the invasion of SUIT-2 and Panc-1 cells. Conclusions CD10+ PSCs enhance the progression of pancreatic cancer cells. CD10+ PSCs may be a candidate for selective therapeutic targeting in the treatment of pancreatic cancer.
Purpose
The aim of this study was to investigate the genetic mutation profiles of Japanese pancreatic ductal adenocarcinoma (PDAC) patients.
Methods
Next-generation sequencing was performed using ...FoundationOne® CDx on 17 PDAC patients who were treated by surgical resection at Kyushu University Hospital between February 2016 and January 2019. The tumor mutational burden and microsatellite instability status were also assessed.
Results
There were 16 patients (94%) with
KRAS
mutations, 13 (76%) with
TP53
mutations, three (18%) with
SMAD4
mutations, and one (6%) with a
CDKN2A
mutation. All patients had at least one pathogenic variant or a likely pathogenic variant. No patient had targeted therapies that matched with any clinical benefit according to FoundationOne® CDx. An unresectable PDAC patient with
BRCA2
-mutant disease was successfully treated by conversion surgery using platinum-based neoadjuvant chemotherapy.
Conclusions
Currently, FoundationOne® CDx might be difficult to use on PDAC patients, although further investigations with larger study populations are called for.
Background
Detection of aberrant microRNA (miR) expression may contribute to diagnosis and prognosis of various cancers. The aim of this study is to evaluate the correlation between miR-203 ...expression and prognosis of patients with pancreatic adenocarcinoma after curative resection.
Methods
A total of 113 formalin-fixed paraffin-embedded tissue samples of pancreatic adenocarcinoma, 20 samples of chronic pancreatitis, and 8 samples of normal pancreas were obtained. We investigated the association of miR-203 expression measured by quantitative reverse-transcription polymerase chain reaction assays with clinicopathological parameters and survival times.
Results
miR-203 was overexpressed in pancreatic adenocarcinoma samples compared with chronic pancreatitis (
P
< 0.001) and normal pancreas (
P
= 0.001) samples. An association between miR-203 expression and clinicopathological factors of pancreatic adenocarcinoma was not observed. On univariate analysis, the high-miR-203 group and the subgroup (20%) of cases with the highest miR-203 overexpression had significantly shorter survival time (
P
= 0.048 and
P
= 0.024, respectively). Multivariate analysis revealed that miR-203 expression was an independent predictor of poor prognosis in cases with no residual tumor (relative risk 2.298,
P
= 0.027).
Conclusions
miR-203 expression is a new prognostic marker in pancreatic adenocarcinoma patients.
Metal–organic frameworks (MOFs) represent the largest class of materials among crystalline porous materials ever developed, and have attracted attention as core materials for separation technology. ...Their extremely uniform pore aperture and nearly unlimited structural and chemical characteristics have attracted great interest and promise for applying MOFs to adsorptive and membrane-based separations. This paper reviews the recent research into and development of MOF membranes for gas separation. Strategies for polycrystalline membranes and mixed-matrix membranes are discussed, with a focus on separation systems involving hydrocarbon separation, CO2 capture, and H2 purification. Challenges to and opportunities for the industrial deployment of MOF membranes are also discussed, providing guidance for the design and fabrication of future high-performance membranes. The contributions of the underlying mechanism to separation performance and adopted strategies and membrane-processing technologies for breaking the selectivity/permeability trade-off are discussed.
Pancreatic ductal adenocarcinoma (PDAC) is characterized by abundant stroma in which microenvironmental (niche) factors promote PDAC progression. In mouse models, reduction of the stroma increased ...the proportion of poorly differentiated PDAC with a worse prognosis. Here, we aimed to clarify the effects of stroma on PDAC that may define the PDAC phenotype and induce distinct therapeutic responses.
The molecular features of PDAC based on differentiation grade were clarified by genome and transcriptome analysis using PDAC organoids (PDOs). We identified the dependency on niche factors that might regulate the differentiation grade. A three-dimensional co-culture model with cancer-associated fibroblasts (CAFs) was generated to determine whether CAFs provide niche factors essential for differentiated PDAC. PDOs were subtyped based on niche factor dependency, and the therapeutic responses for each subtype were compared.
The expression profiles of PDOs differed depending on the differentiation grade. Consistent with the distinct profiles, well differentiated types showed high niche dependency, while poorly differentiated types showed low niche dependency. The three-dimensional co-culture model revealed that well differentiated PDOs were strongly dependent on CAFs for growth, and moderately differentiated PDOs showed plasticity to change morphology depending on CAFs. Differentiated PDOs upregulated the expression of mevalonate pathway-related genes correlated with the niche dependency and were more sensitive to simvastatin than poorly differentiated PDOs.
Our findings suggest that CAFs maintain the differentiated PDAC phenotype through secreting niche factors and induce distinct drug responses. These results may lead to the development of novel subtype-based therapeutic strategies.
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