Immune checkpoint blockade therapy with anti-PD-1 monoclonal antibody (mAb) is a treatment for colorectal cancer (CRC). However, some patients remain unresponsive to PD-1 blockade. The gut microbiota has been linked to immunotherapy resistance through unclear mechanisms.
View Article and Find Full Text PDFBackground: As newly identified Wnt enhancer, R-spondin gene family members have been linked to various cancers; however, their role in isocitrate dehydrogenase-wildtype subtype of human glioblastoma (GBM) cells remains unknown.
Methods: Human U87 and U251 cell lines were used to perform the experiments. GBM stem-like cells were enriched in stem cell growth media and induced to differentiate using retinoid acid or growth factor deprivation.
Background: Gastric cancer is a heterogeneous malignant disease associated with environmental and genetic predisposing factors. While gastric cancer incidence and mortality fell greatly globally over the past decades, it remains the fourth cause of cancer-related death worldwide. Thus, prevention of gastric cancer is still a major strategy for improvement of gastric cancer prognosis.
View Article and Find Full Text PDFBone marrow-derived cells have important roles in cancer development and progression. Our previous studies demonstrated that murine bone marrow-derived myofibroblasts (BMFs) enhanced tumor growth. In this study, we investigated the mechanisms of BMF actions.
View Article and Find Full Text PDFSurvivin overexpression is associated with poor prognosis of human gastric cancer, and is a target for gastric cancer therapy. YM155 is originally identified as a specific inhibitor of survivin. In this study, we investigated the antitumor effect of YM155 on human gastric cancer.
View Article and Find Full Text PDFX-linked inhibitor of apoptosis (XIAP)-associated factor 1 (XAF1), a XIAP-binding protein, is a tumor suppressor gene. XAF1 was silent or expressed lowly in most human malignant tumors. However, the role of XAF1 in hepatocellular carcinoma (HCC) remains unknown.
View Article and Find Full Text PDFBone marrow-derived myofibroblasts (BMFs) have been shown to promote tumor growth. Here, we found that BMFs or BMF conditioned medium (BMF-CM) induced cancer stem cell-like sphere formation of colon cancer cells. The co-cultured BMFs, but not co-cultured cancer cells, expressed higher levels of IL-6 than BMFs or cancer cells cultured alone.
View Article and Find Full Text PDFBleomycin causes acute lung injury through production of reactive species and initiation of inflammation. Previous work has shown alteration to the production of reactive oxygen species results in attenuation of injury. Vitamin E, in particular, γ-tocopherol, isoform, has the potential to scavenge reactive oxygen and nitrogen species.
View Article and Find Full Text PDFMyeloid-derived suppressor cells (MDSC) accumulate in the spleen and tumors and contribute to tumor growth, angiogenesis, and progression. In this study, we examined the effects of curcumin on the activation and differentiation of MDSCs, their interaction with human cancer cells, and related tumor growth. Treatment with curcumin in the diet or by intraperitoneal injection significantly inhibited tumorigenicity and tumor growth, decreased the percentages of MDSCs in the spleen, blood, and tumor tissues, reduced interleukin (IL)-6 levels in the serum and tumor tissues in a human gastric cancer xenograft model and a mouse colon cancer allograft model.
View Article and Find Full Text PDFAutophagy is designated as type II programmed cell death and may confer a tumor-suppressive function. Our previous studies have shown that XIAP-associated factor 1 (XAF1) induced apoptosis and inhibited tumor growth in gastric cancer cells. In this study, we investigated the effect of XAF1 on the induction of autophagy in gastric cancer cells.
View Article and Find Full Text PDFIFN-γ mediates responses to bacterial infection and autoimmune disease, but it is also an important tumor suppressor. It is upregulated in the gastric mucosa by chronic Helicobacter infection; however, whether it plays a positive or negative role in inflammation-associated gastric carcinogenesis is unexplored. To study this question, we generated an H(+)/K(+)-ATPase-IFN-γ transgenic mouse that overexpresses murine IFN-γ in the stomach mucosa.
View Article and Find Full Text PDFCarcinoma-associated fibroblasts (CAFs) that express α-smooth muscle actin (αSMA) contribute to cancer progression, but their precise origin and role are unclear. Using mouse models of inflammation-induced gastric cancer, we show that at least 20% of CAFs originate from bone marrow (BM) and derive from mesenchymal stem cells (MSCs). αSMA+ myofibroblasts (MFs) are niche cells normally present in BM and increase markedly during cancer progression.
View Article and Find Full Text PDFColon cancer is one of the most common cancers. Survivin is overexpressed in human colon cancer and correlate with chemoresistance, angiogenesis and poor prognosis. Oxaliplatin, a platinum derivative cancer drug, has been used for treating human colorectal cancers.
View Article and Find Full Text PDFBackground: XIAP-associated factor 1 (XAF1) antagonizes the anticaspase activity of XIAP (X-linked inhibitor of apoptosis) and functions as a tumor suppressor in colon cancer. The tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) is known as a potential anticancer agent. In this study, the synergistic effect of XAF1 and TRAIL on colon cancer growth was investigated.
View Article and Find Full Text PDFThe risk of pancreatic cancer is increased in both Snus (the Swedish variant of oral smokeless tobacco) users and, to a greater extent, in cigarette smokers. Concurrent chronic pancreatitis further increases the risk in cigarette smokers. Little is known about the mechanism by which cigarette smoke or Snus increase the risk of pancreatic cancer in individuals with chronic pancreatitis.
View Article and Find Full Text PDFXAF1 (X chromosome-linked inhibitor of apoptosis [XIAP]-associated factor 1) is a novel XIAP modulator that negatively regulates the anti-apoptotic effects of XIAP and sensitizes cells to other cell death triggers. It has been reported to be downregulated in a variety of human cancer cell lines. However, the role of XAF1 in pancreatic carcinogenesis remains unclear.
View Article and Find Full Text PDFRecent studies with Helicobacter-infected mice have shown that bone marrow-derived cells can repopulate the gastric epithelium and progress to cancer. However, it has not been established which cellular subset can potentially contribute to the epithelium. The aim of this study was to investigate the ability of bone marrow-derived mesenchymal stem cells (MSCs) that express cytokeratin 19 (K19) to contribute to the gastric epithelium.
View Article and Find Full Text PDFAm J Physiol Gastrointest Liver Physiol
August 2009
Overexpression of trefoil factor 2 (TFF2) is associated with increased cell migration, resistance to apoptosis, and possibly increased gastric cancer invasion. Dysregulation of p53 is frequently observed in preneoplastic conditions of the stomach. Here, we investigated the effect of p53 on the expression and function of TFF2 in gastric cancer cell lines.
View Article and Find Full Text PDFXAF1 (XIAP-associated factor 1) is a novel XIAP binding protein that can antagonize XIAP and sensitize cells to other cell death triggers. Our previous results have shown that aberrant hypermethylation of the CpG sites in XAF1 promoter is strongly associated with lower expression of XAF1 in gastric cancers. In our study, we investigated the effect of restoration of XAF1 expression on growth of gastric cancers.
View Article and Find Full Text PDFBackground & Aims: Chronic pancreatitis is a significant cause of morbidity and a known risk factor for pancreatic adenocarcinoma. Interleukin-1beta is a proinflammatory cytokine involved in pancreatic inflammation. We sought to determine whether targeted overexpression of interleukin-1beta in the pancreas could elicit localized inflammatory responses and chronic pancreatitis.
View Article and Find Full Text PDFBackground & Aims: X-linked inhibitor of apoptosis protein (XIAP)-associated factor 1 (XAF1) antagonizes the anti-caspase activity of XIAP. XAF1 messenger RNA is present in normal tissues but undetectable in various cancers and thus poses a potential tumor suppressor gene. The aim of this study was to examine the novel pattern of methylation of XAF1 in gastric and colon cancers and locate the important CpG sites for transcriptional regulation and tumor progression.
View Article and Find Full Text PDFZhonghua Yi Xue Za Zhi
December 2004
Objective: To investigate the activation of signal transducers and activators of transcription 3 (Stat3) in different types of gastric cancer cell lines and tissues and evaluate the relationship with their clinicopathological parameters.
Methods: Western blotting and electrophoretic mobility shift assay (EMSA) were used to detected the expression of Stat3 protein and Stat3 DNA-binding activity in normal human gastric epithelial cell line 3T3 and five gastric cancer cell lines with different differentiation: MKN28, SGC7901, MKN45, AGS and NCI-SNU-1, respectively. The localization of phospho-Stat3 was determined by immunocytochemistry.
Background And Aims: Reactivation of survivin expression is involved in carcinogenesis and angiogenesis in colon cancer. Previous in vitro studies showed that mutation of the cysteine residue at position 84 (Cys84Ala) of survivin generates a dominant-negative mutant that triggers mitotic catastrophe and apoptosis. We investigated the therapeutic effect of the adeno-associated virus (AAV)-mediated survivin mutant (Cys84Ala) on colon cancer.
View Article and Find Full Text PDFAspirin-induced apoptosis is one of the important mechanisms for its antitumour effect against gastric cancer. We aimed at investigating the involvement of bcl-2 family members in the apoptotic pathway in gastric cancer. Gastric cancer cell line AGS and MKN-45 were observed as to cell growth inhibition and induction of apoptosis in response to treatment with aspirin.
View Article and Find Full Text PDFProtein kinase C (PKC) family, which functions through serine/threonine kinase activity, is involved in signal transduction pathways necessary for cell proliferation, differentiation, and apoptosis. Its critical role in neoplastic transformation and tumor invasion renders PKC a potential target for anticancer therapy. In this study, we investigated the effect of targeting individual PKCs on gastric carcinogenesis.
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