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1.
Nucleic Acids Res ; 51(19): 10768-10781, 2023 10 27.
Article in English | MEDLINE | ID: mdl-37739431

ABSTRACT

Translational readthrough of UGA stop codons by selenocysteine-specific tRNA (tRNASec) enables the synthesis of selenoproteins. Seryl-tRNA synthetase (SerRS) charges tRNASec with serine, which is modified into selenocysteine and delivered to the ribosome by a designated elongation factor (eEFSec in eukaryotes). Here we found that components of the human selenocysteine incorporation machinery (SerRS, tRNASec, and eEFSec) also increased translational readthrough of non-selenocysteine genes, including VEGFA, to create C-terminally extended isoforms. SerRS recognizes target mRNAs through a stem-loop structure that resembles the variable loop of its cognate tRNAs. This function of SerRS depends on both its enzymatic activity and a vertebrate-specific domain. Through eCLIP-seq, we identified additional SerRS-interacting mRNAs as potential readthrough genes. Moreover, SerRS overexpression was sufficient to reverse premature termination caused by a pathogenic nonsense mutation. Our findings expand the repertoire of selenoprotein biosynthesis machinery and suggest an avenue for therapeutic targeting of nonsense mutations using endogenous factors.


Subject(s)
Protein Biosynthesis , Serine-tRNA Ligase , Humans , Codon, Nonsense , Codon, Terminator , RNA, Messenger/metabolism , Selenocysteine/genetics , Selenocysteine/metabolism , Selenoproteins/genetics , Serine-tRNA Ligase/genetics
2.
Front Oncol ; 11: 738144, 2021.
Article in English | MEDLINE | ID: mdl-34737955

ABSTRACT

Many studies reported that microRNAs (miRNAs) target autophagy-related genes to affect carcinogenesis, however, autophagy-deficiency-related miRNA dysfunction in cancer development remains poorly explored. During autophagic progression, we identified miR-449a as the most up-regulated miRNA. MiR-449a expression was low in the tumor parts of CRC patient specimens and inversely correlated with tumor stage and metastasis with the AUC (area under the curve) of 0.899 and 0.736 as well as poor overall survival rate, indicating that miR-449a has the potential to be a prognostic biomarker. In the same group of CRC specimens, low autophagic activity (low Beclin 1 expression and high p62 accumulation) was detected, which was significantly associated with miR-449a expression. Mechanistic studies disclosed that autophagy upregulates miR-449a expression through degradation of the coactivator p300 protein which acetylates the transcription factor Forkhead Box O1 (FoxO1). Unacetylated FoxO1 translocated to the nucleus and bound to the miR-449a promoter to drive gene expression. Either activation of autophagy by the inducer or overexpression of exogenous miR-449a decreases the expression of target gene LEF-1 and cyclin D1, which lead to decreased proliferation, colony formation, migration, and invasion of CRC cells. Autophagy-miR-449a-tartet genes mediated suppression of tumor formation was further confirmed in the xenograft mouse model. In conclusion, this study reveals a novel mechanism wherein autophagy utilizes miR-449a-LEF1-cyclin D1 axis to suppress CRC tumorigenesis. Our findings open a new avenue toward prognosis and treatment of CRC patients by manipulating autophagy-miR-449a axis.

3.
Pathol Res Pract ; 217: 153288, 2021 Jan.
Article in English | MEDLINE | ID: mdl-33276219

ABSTRACT

Microsatellite instability (MSI) is reflective of a deficient mismatch repair (dMMR) system, which is mostly associated with the methylation of mismatch repair (MMR) genes and BRAF mutations in sporadic colorectal cancers (CRCs). We performed a retrospective study to analyze the clinicopathological features of dMMR CRCs and their association with the BRAF V600E mutation. The incidence of dMMR CRCs in our cohort was 7.4 % (118/1603). Immunohistochemistry (IHC) revealed four common dMMR IHC patterns in 116 dMMR CRCs from 110 patients. dMMR type 1 (MLH1-/PMS2-) CRCs were the most frequent pattern, usually showing typical proximal location and MSI histology. The BRAF V600E mutation was almost exclusively observed in dMMR type 1 (32 of 72) and dMMR type 2 (PMS- only, 7 of 18) CRCs (p = 0.001). Patients with dMMR type 3 (MSH2-/MSH6-) CRCs were usually diagnosed at younger ages (p < 0.001) and had the strongest family history of Lynch syndrome-associated tumors (p = 0.002). dMMR type 3 CRCs frequently presented at advanced stages (p = 0.005) with perineural invasion (p = 0.021). We also found a significant positive association of dMMR type 1 and type 3 with advanced stages of CRC, whereas dMMR types 2 and 4 (MSH6- only) were usually diagnosed at early stages of CRC (p < 0.001). In conclusion, BRAF V600E mutations almost exclusively occurred in dMMR type 1 and 2 CRCs. Patterns of MMR protein expression display distinct associations with tumor staging and age at diagnosis.


Subject(s)
Biomarkers, Tumor/analysis , Colorectal Neoplasms/enzymology , DNA Mismatch Repair , DNA Repair Enzymes/analysis , Microsatellite Instability , Adult , Age Factors , Aged , Aged, 80 and over , Colorectal Neoplasms/genetics , Colorectal Neoplasms/pathology , Female , Genetic Predisposition to Disease , Humans , Male , Middle Aged , Mutation , Neoplasm Staging , Phenotype , Proto-Oncogene Proteins B-raf/genetics , Retrospective Studies
4.
Biochem Biophys Res Commun ; 530(3): 487-493, 2020 09 24.
Article in English | MEDLINE | ID: mdl-32595041

ABSTRACT

Gout is an inflammatory arthritis caused by the phagocytosis of monosodium urate (MSU) crystal deposition in joints. NOD-, LRR-, and pyrin domain-containing 3 (NLRP3) inflammasome-dependent caspase-1 activation is implicated in the processing of interleukin-1ß (IL-1ß), which is the major effector cytokine in the acute inflammatory response of gout. Mechanisms underlying caspase-1 activation remain unclear. Epidermal growth factor receptor pathway substrate no. 8 (Eps8) is a signal transducer and actin filament organizer that plays a key role in lipopolysaccharide-stimulated phagocytosis in macrophages. Here, RAW264.7 macrophages that have no intact NLRP3 inflammasomes were used to investigate the role of Eps8 in MSU crystal-mediated caspase-1 activation. A kinetic study revealed that the induction of Eps8 expression by MSU crystals occurred before NLRP3, p46/p33 caspase-1, and mature IL-1ß in RAW 264.7 cells. In addition, actin cytoskeleton dynamics was required for Eps8 induction and caspase-1 activation in MSU crystal stimulation. Silencing Eps8 had no effect on the basal expression of p46/p33 caspase-1 and NLRP3, but nearly abolished MSU crystal-induced NLRP3 expression and caspase-1 activation. Furthermore, MSU crystals induced Eps8-pro-caspase-1 complex formation and Eps8 formed a stable complex with p33 caspase-1, but not with NLRP3. In summary, our results demonstrated for the first time the importance of Eps8 in MSU crystal-mediated caspase-1 activation without the involvement of NLRP3 inflammasomes.


Subject(s)
Adaptor Proteins, Signal Transducing/metabolism , Caspase 1/metabolism , Gout/metabolism , Inflammasomes/metabolism , NLR Family, Pyrin Domain-Containing 3 Protein/metabolism , Uric Acid/metabolism , Animals , Enzyme Activation/drug effects , Gout/pathology , Inflammation/metabolism , Inflammation/pathology , Macrophages/metabolism , Macrophages/pathology , Mice , RAW 264.7 Cells
5.
Asian J Surg ; 43(11): 1069-1073, 2020 Nov.
Article in English | MEDLINE | ID: mdl-31974054

ABSTRACT

BACKGROUND: The metastatic pattern differs between colon cancer and rectal cancer because of the distinct venous drainage systems. It is unclear whether colon cancer and rectal cancer are associated with different prognostic factors based on the anatomic difference. METHODS: We assessed the prognostic factors and survival outcomes of patients with colorectal cancer who underwent pulmonary metastasectomy (PM), disaggregated by the location of primary colorectal cancer. The Cox proportional hazards model was used to identify variables that influenced the outcomes of pulmonary metastasectomy. RESULTS: Between 2008 and 2017, 179 patients underwent PM classified into colon cancer and rectal cancer groups based on the site of origin of metastasis. The median postoperative follow-up was 2.3 years (range, 0.1-10.6). The post-PM 5-year survival rate in the colon cancer and rectal cancer groups was 42.5% and 39.9%, respectively (p = 0.310). On multivariable Cox proportional hazards analysis, presence of previous liver metastasis [hazard ratio (HR), 2.32; 95% confidence interval (CI), 1.19-4.51; p = 0.013], numbers of tumors (≥2; HR, 6.56; 95% CI, 2.07-20.79; p = 0.001), and abnormal preoperative carcinoembryonic antigen (CEA) level (HR, 2.50; 95% CI, 1.34-4.64; p = 0.001) were independent prognostic factors in patients with metastatic rectal cancer. CONCLUSIONS: Prognostic correlates of post-PM survival differ between colon and rectal cancer. Rectal cancer patients have worse prognosis if they have a history of liver metastasis, multiple pulmonary metastases, or abnormal preoperative CEA. These results may help assess the survival benefit of PM and facilitate treatment decision-making.


Subject(s)
Colorectal Neoplasms/pathology , Lung Neoplasms/secondary , Lung Neoplasms/surgery , Aged , Colorectal Neoplasms/mortality , Female , Follow-Up Studies , Humans , Lung Neoplasms/mortality , Male , Middle Aged , Pneumonectomy , Prognosis , Proportional Hazards Models , Survival Rate , Thoracic Surgery, Video-Assisted
6.
Cancer Lett ; 472: 97-107, 2020 03 01.
Article in English | MEDLINE | ID: mdl-31875524

ABSTRACT

Many Aurora-A inhibitors have been developed for cancer therapy; however, the specificity and safety of Aurora-A inhibitors remain uncertain. The Aurora-A mRNA yields nine different 5'-UTR isoforms, which result from mRNA alternative splicing. Interestingly, we found that the exon 2-containing Aurora-A mRNA isoforms are predominantly expressed in cancer cell lines as well as human colorectal cancer tissues, making the Aurora-A mRNA exon 2 a promising treatment target in Aurora-A-overexpressing cancers. In this study, a selective siRNA, siRNA-2, which targets Aurora-A mRNA exon 2, was designed to translationally inhibit the expression of Aurora-A in cancer cells but not normal cells; locked nucleic acid (LNA)-modified siRNA-2 showed improved efficacy in inhibiting Aurora-A mRNA translation and tumor growth. Xenograft animal models combined with noninvasion in vivo imaging system (IVIS) analysis further confirmed the anticancer effect of LNA-siRNA-2 with improved efficiency and safety and reduced side effects. Mice orthotopically injected with colorectal cancer cells, LNA-siRNA-2 treatment not only inhibited the tumor growth but also blocked liver and lung metastasis. The results of our study suggest that LNA-siRNA-2 has the potential to be a novel therapeutic agent for cancer treatment.


Subject(s)
Aurora Kinase A/genetics , Cell Proliferation/drug effects , Colorectal Neoplasms/genetics , Protein Isoforms/genetics , 5' Untranslated Regions/drug effects , Alternative Splicing/genetics , Animals , Aurora Kinase A/antagonists & inhibitors , Colorectal Neoplasms/pathology , HCT116 Cells , Humans , Mice , Neoplasm Metastasis , Oligonucleotides/pharmacology , Protein Isoforms/antagonists & inhibitors , RNA, Messenger/genetics , RNA, Small Interfering/pharmacology , Xenograft Model Antitumor Assays
7.
Cancer Manag Res ; 11: 7867-7875, 2019.
Article in English | MEDLINE | ID: mdl-31692488

ABSTRACT

PURPOSE: Human epidermal growth factor receptor 2 (HER2) is an emerging therapeutic target in colorectal cancer (CRC). Currently, immunohistochemistry (IHC) and fluorescence in situ hybridization (FISH) have been used to determine HER2-positive CRCs; however, the clinical utility of next-generation sequencing (NGS)-based techniques for determining HER2 status in CRC has been limited. Here, we detail our experience regarding the assessment of HER2 alterations in a CRC cohort. MATERIALS AND METHODS: We prospectively enrolled 73 CRC patients who underwent surgery and received adjuvant oxaliplatin treatment. We then examined HER2 alterations using the Oncomine Comprehensive Assay version 1, as well as clinical outcomes, in this cohort. RESULTS: Using the NGS-based assay, HER2 copy number gains in 12 of 73 CRCs were determined to range from 2.74 to 92.62. Of these 12 tumors, 6 had HER2 high-level copy number gain (92.6, 57.9, 57.0, 52.0, 35.2, and 8.42) and were all defined as HER2-positive CRC using HERACLES Diagnostic Criteria. Nevertheless, other 6 patients with low-level copy number gain (ranging from 2.74 to 3.04) and the remaining 61 patients without increase in HER2 copy number were all HER2-negative. Among the 6 HER2-positive CRCs, KRAS and PIK3CA mutations were detected in 1 (17%; G13D) and 2 (33.3%; 1 Q546R and 1 H1047R) patients, respectively. Moreover, 2 of the 6 (33.3%) HER2-positive patients had recurrent disease, while one patient had a partial response after anti-HER2 therapy. CONCLUSION: NGS-based tools could assist in the simultaneous detection of HER2 and other genomic alterations in patients with CRC. Only CRCs with HER2 high-level copy number gain were HER2-postive by current diagnostic criteria.

8.
BMJ Open ; 9(10): e028892, 2019 10 09.
Article in English | MEDLINE | ID: mdl-31601586

ABSTRACT

OBJECTIVES: This study aimed to determine colorectal cancer (CRC) risks among patients with gout through a follow-up study on a nationwide population-based cohort that included patients with gout and the general population in Taiwan. PARTICIPANT: From the Taiwan National Health Insurance Research Database, we identified 28 061 patients who were newly diagnosed with gout between 2000 and 2010 as the study cohort. We randomly selected 84 248 subjects matching in gender, age and baseline year as comparison cohort. The cohorts were followed up until CRC occurrence, withdrawal from the system of National Health Insurance, or Dec. 31, 2013. PRIMARY AND SECONDARY OUTCOME MEASURES: Cumulative incidences and incidence rate ratios (IRRs) of CRC between two cohorts were examined. The Cox proportional hazards model was used to evaluate risk factors associated with CRC development. RESULTS: During the 13-year follow-up, the incidence rate of CRC development in the gout cohort reached 2.44 per 1000 person-years, which was higher than the 2.13 per 1000 person-years in the control cohort (IRR=1.15; 95% CI 1.04 to 1.26). After adjusting for age, gender, urbanisation status and comorbidities, including hypertension, diabetes and hyperlipidaemia, gout showed no significant association with increased risk of CRC occurrence (adjusted HR=1.03; 95% CI 0.93 to 1.14). CONCLUSIONS: Similar risks of CRC incidence were observed in patients with and without gout in Taiwan. Allopurinol and colchicine are commonly used as urate-lowering drug and anti-inflammation medication in Taiwan and had been shown to reduce the risk of CRC incidence. Thus, further pharmaco-epidemiological studies should be carried out to specifically assess the role of allopurinol in the relationship between gout and CRC.


Subject(s)
Colorectal Neoplasms/epidemiology , Gout/epidemiology , Adult , Aged , Allopurinol/therapeutic use , Colchicine/therapeutic use , Comorbidity , Databases, Factual , Diabetes Mellitus/epidemiology , Female , Follow-Up Studies , Gout/drug therapy , Humans , Hyperlipidemias/epidemiology , Hypertension/epidemiology , Incidence , Kaplan-Meier Estimate , Male , Middle Aged , Proportional Hazards Models , Retrospective Studies , Risk Factors , Taiwan/epidemiology
9.
Medicina (Kaunas) ; 55(4)2019 Apr 14.
Article in English | MEDLINE | ID: mdl-31013982

ABSTRACT

Background and objective: Risk of secondary prostate cancer after radiation therapy among patients with rectal cancer remains undetermined. Given an increased incidence of rectal cancer in younger people and improved survival for rectal cancer patients who received radiation therapy, the potential risk of secondary prostate cancer needs to be further investigated. Materials and Methods: Male patients (n = 11,367) newly diagnosed rectal cancer and who underwent abdominoperineal resection (APR) or low anterior resection (LAR) from 1 January, 1998 to 31 December, 2010 were identified from Taiwan National Health Insurance Research Database. The incidence and relative risk of secondary prostate cancer in study patients with (n = 1586) and without (n = 9781) radiotherapy within one year after rectal cancer diagnosis were compared using a competing-risks analysis. Results: Rectal cancer patients with radiotherapy were at a significantly decreased risk of developing prostate cancer, with a hazard ratio (HR) of 0.41 (95% confidence interval = 0.20⁻0.83) after adjustment for age. Analysis of the risk estimated for various follow-up lengths suggested that a decreasing HR was seen through the period followed-up and that there was a trend of decreasing prostate cancer risk with time after radiotherapy. Conclusions: Radiotherapy was significantly associated with decreased risk of secondary prostate cancer among rectal cancer patients, by a magnitude of 59%.


Subject(s)
Neoplasms, Second Primary/epidemiology , Prostatic Neoplasms/epidemiology , Radiotherapy, Adjuvant/adverse effects , Rectal Neoplasms/epidemiology , Rectal Neoplasms/radiotherapy , Adolescent , Adult , Aged , Aged, 80 and over , Follow-Up Studies , Humans , Incidence , Male , Middle Aged , Multivariate Analysis , Proportional Hazards Models , Retrospective Studies , Taiwan/epidemiology , Young Adult
10.
EBioMedicine ; 43: 270-281, 2019 May.
Article in English | MEDLINE | ID: mdl-30982765

ABSTRACT

BACKGROUND: In our preliminary screening, expression of miR-338-5p was found to be higher in primary colorectal cancer (CRC) with metastasis. The autophagy related gene- phosphatidylinositol 3-kinase, catalytic subunit type 3 (PIK3C3) appeared to be targeted by miR-338-5p. Here, we provide solid evidence in support of PIK3C3 involved in miR-338-5p related metastasis of CRC in vitro and in vivo. METHODS: The potential clinical relevance of miR-338-5p and its target gene was analysed on benign colorectal polyps and primary CRCs by QPCR. Mouse spleen xenograft experiment was performed to examine the importance of miR-338-5p for metastasis. FINDINGS: PIK3C3 was one of target genes of miR-338-5p. In primary CRCs, expression of miR-338-5p is positively related to tumour staging, distant metastasis and poor patient survival. Patients with higher ratios of miR-338-5p/PIK3C3 also had significantly poor overall survival, supporting their significance in the progression of CRC. Over-expression of miR-338-5p promotes CRC metastasis to the liver and lung in vivo, in which PIK3C3 was down-regulated in the metastatic tumours. In contrast, overexpression of PIK3C3 in miR-338-5p stable cells inhibited the growth of metastatic tumours. Both migration and invasion of CRC in vitro induced by miR-338-5p are mediated by suppression of PIK3C3. Using forward and reverse approaches, autophagy was proved to involve in CRC migration and invasion induced by miR-338-5p. INTERPRETATION: MiR-338-5p induces migration, invasion and metastasis of CRC in part through PIK3C3-related autophagy pathway. The miR-338-5p/PIK3C3 ratio may become a prognostic biomarker for CRC patients. FUND: NCKU Hospital, Taiwan, Ministry of Science and Technology, Taiwan.


Subject(s)
Autophagy/genetics , Class I Phosphatidylinositol 3-Kinases/genetics , Colorectal Neoplasms/genetics , Colorectal Neoplasms/metabolism , Gene Expression Regulation, Neoplastic , MicroRNAs/genetics , RNA Interference , 3' Untranslated Regions , Animals , Cell Line, Tumor , Cell Movement/genetics , Colorectal Neoplasms/pathology , Disease Models, Animal , Humans , Mice , Neoplasm Metastasis , Neoplasm Staging , Signal Transduction , Xenograft Model Antitumor Assays
11.
Exp Mol Med ; 50(6): 1-14, 2018 06 06.
Article in English | MEDLINE | ID: mdl-29884818

ABSTRACT

Heterogeneous nuclear ribonucleoprotein (hnRNP) Q1, an RNA-binding protein, has been implicated in many post-transcriptional processes, including RNA metabolism and mRNA splicing and translation. However, the role of hnRNP Q1 in tumorigenesis remains unclear. We previously performed RNA immunoprecipitation (RIP)-seq analysis to identify hnRNP Q1-interacting mRNAs and found that hnRNP Q1 targets a group of genes that are involved in mitotic regulation, including Aurora-A. Here, we demonstrate that altering the hnRNP Q1 level influences the expression of the Aurora-A protein, but not its mRNA. Stimulation with epidermal growth factor (EGF) enhances both binding between hnRNP Q1 and Aurora-A mRNA as well as the efficacy of the hnRNP Q1-induced translation of Aurora-A mRNA. The EGF/hnRNP Q1-induced translation of Aurora-A mRNA is mediated by the mTOR and ERK pathways. In addition, we show that hnRNP Q1 up-regulates the translation of a group of spindle assembly checkpoint (SAC) genes. hnRNP Q1 overexpression is positively correlated with the levels of Aurora-A and the SAC genes in human colorectal cancer tissues. In summary, our data suggest that hnRNP Q1 plays an important role in regulating the expression of a group of cell cycle-related genes. Therefore, it may contribute to tumorigenesis by up-regulating the translation of these genes in colorectal cancer.


Subject(s)
Cell Transformation, Neoplastic/metabolism , Colorectal Neoplasms/metabolism , Epidermal Growth Factor/metabolism , Heterogeneous-Nuclear Ribonucleoproteins/metabolism , MAP Kinase Signaling System , Mitosis , Neoplasm Proteins/metabolism , Cell Transformation, Neoplastic/genetics , Cell Transformation, Neoplastic/pathology , Colorectal Neoplasms/genetics , Colorectal Neoplasms/pathology , Epidermal Growth Factor/genetics , HCT116 Cells , Heterogeneous-Nuclear Ribonucleoproteins/genetics , Humans , Neoplasm Proteins/genetics
12.
Sci Rep ; 7(1): 5823, 2017 07 19.
Article in English | MEDLINE | ID: mdl-28725043

ABSTRACT

Downregulation of Mucin 2 (MUC2) expression is associated with early carcinogenesis events in colon cancer. MUC2 plays a role in the progression of colon cancer, and reduced MUC2 protein expression correlates with increased interleukin-6 (IL-6) expression. However, the interaction between MUC2 and IL-6 in colorectal cancer metastasis remains unclear. We systematically analyzed MUC2 and IL-6 expression and determined the survival of cancer patients with high or low MUC2 and IL-6 expression using the Oncomine and PrognoScan databases, respectively. This analysis identified downregulation of MUC2 and overexpression of IL-6 in colon cancer but not in normal colon tissue, and this expression pattern was correlated with poor survival of colon cancer patients. We examined the effects of MUC2 on colon cancer metastasis and used vector-mediated application of short hairpin RNA (shRNA) to suppress MUC2 expression. MUC2 suppressed the migration of colon cancer cells in vitro and dramatically diminished liver metastases in vivo. Treatment with IL-6 increased signal transducer and activator of transcription 3 (STAT3) phosphorylation, promoted checkpoint kinase 2 (Chk2) activation, attenuated cAMP response element-binding protein (CREB) phosphorylation, and suppressed E-cadherin protein expression in MUC2-silenced HT-29 cancer cells. Most importantly, MUC2 is a potential prognostic indicator for colon cancer.


Subject(s)
Colonic Neoplasms/genetics , Colonic Neoplasms/pathology , Gene Silencing , Interleukin-6/metabolism , Liver Neoplasms/secondary , Mucin-2/genetics , Animals , Antigens, CD/metabolism , Antigens, Differentiation, Myelomonocytic/metabolism , Cadherins/metabolism , Cell Line, Tumor , Cell Movement/genetics , Cell Proliferation , Gene Expression Regulation, Neoplastic , Humans , Interleukin-6/genetics , Kaplan-Meier Estimate , Macrophages/metabolism , Mice , Mucin-2/metabolism , Signal Transduction
13.
Cancer Res ; 77(16): 4305-4316, 2017 08 15.
Article in English | MEDLINE | ID: mdl-28652251

ABSTRACT

Cancer stem-like cells (CSC) evolve to overcome the pressures of reduced oxygen, nutrients or chemically induced cell death, but the mechanisms driving this evolution are incompletely understood. Here, we report that hypoxia-mediated downregulation of the dual specificity phosphatase 2 (DUSP2) is critical for the accumulation of CSC in colorectal cancer. Reduced expression of DUSP2 led to overproduction of COX-2-derived prostaglandin E2, which promoted cancer stemness via the EP2/EP4 signaling pathways. Genetic and pharmacological inhibition of PGE2 biosynthesis or signal transduction ameliorated loss-of-DUSP2-induced tumor growth and cancer stemness. Genome-wide profile analysis revealed that genes regulated by DUSP2 were similar to those controlled by histone deacetylase. Indeed, treatment with novel histone deacetylase inhibitors abolished hypoxia-induced DUSP2 downregulation, COX-2 overexpression, cancer stemness, tumor growth, and drug resistance. Our findings illuminate mechanisms of cancer stemness and suggest new cancer therapy regimens. Cancer Res; 77(16); 4305-16. ©2017 AACR.


Subject(s)
Cell Hypoxia/physiology , Colorectal Neoplasms/enzymology , Colorectal Neoplasms/pathology , Dual Specificity Phosphatase 2/metabolism , Neoplastic Stem Cells/enzymology , Neoplastic Stem Cells/pathology , Animals , Caco-2 Cells , Cell Line, Tumor , Down-Regulation , HCT116 Cells , HT29 Cells , Heterografts , Humans , Male , Mice , Mice, SCID , Signal Transduction
14.
Oncotarget ; 8(21): 35165-35175, 2017 May 23.
Article in English | MEDLINE | ID: mdl-28422723

ABSTRACT

Colorectal mucinous adenocarcinoma (MAC) and serrated adenocarcinoma (SAC) share many characteristics, including right-side colon location, frequent mucin production, and various molecular features. This study examined the frequency of SAC morphology in MACs. We assessed the correlation of SAC morphology with clinicopathological parameters, molecular characteristics, and patient prognosis. Eighty-eight colorectal MACs were collected and reviewed for SAC morphology according to Makinen's criteria. We sequenced KRAS and BRAF, assessed CpG island methylator phenotype (CIMP) frequency, and analyzed DNA mismatch repair enzyme levels using immunohistochemistry in tumor samples. SAC morphology was observed in 38% of MACs, and was associated with proximal location (P=0.001), BRAF mutation (P=0.042), CIMP-positive status (P=0.023), and contiguous traditional serrated adenoma (P=0.019). Multivariate analysis revealed that MACs without both SAC morphology and CIMP-positive status exhibited 3.955 times greater risk of cancer relapse than MACs having both characteristics or either one (P=0.035). Our results show that two MAC groups with distinct features can be identified using Makinen's criteria, and suggest a favorable prognostic role for the serrated neoplastic pathway in colorectal MAC.


Subject(s)
Adenocarcinoma, Mucinous/pathology , Colorectal Neoplasms/pathology , MutL Protein Homolog 1/metabolism , MutS Homolog 2 Protein/metabolism , Proto-Oncogene Proteins B-raf/genetics , Proto-Oncogene Proteins p21(ras)/genetics , Adenocarcinoma, Mucinous/classification , Adenocarcinoma, Mucinous/genetics , Adenocarcinoma, Mucinous/metabolism , Aged , Colorectal Neoplasms/classification , Colorectal Neoplasms/genetics , Colorectal Neoplasms/metabolism , CpG Islands , DNA Methylation , Female , Humans , Male , Neoplasm Staging , Prognosis , Sequence Analysis, DNA , Survival Analysis
15.
Cell Death Dis ; 8(1): e2555, 2017 01 12.
Article in English | MEDLINE | ID: mdl-28079881

ABSTRACT

By using RNA-immunoprecipitation assay following next-generation sequencing, a group of cell cycle-related genes targeted by hnRNP Q1 were identified, including Aurora-A kinase. Overexpressed hnRNP Q1 can upregulate Aurora-A protein, but not alter the mRNA level, through enhancing the translational efficiency of Aurora-A mRNA, either in a cap-dependent or -independent manner, by interacting with the 5'-UTR of Aurora-A mRNA through its RNA-binding domains (RBDs) 2 and 3. By ribosomal profiling assay further confirmed the translational regulation of Aurora-A mRNA by hnRNP Q1. Overexpression of hnRNP Q1 promotes cell proliferation and tumor growth. HnRNP Q1/ΔRBD23-truncated mutant, which loses the binding ability and translational regulation of Aurora-A mRNA, has no effect on promoting tumor growth. The expression level of hnRNP Q1 is positively correlated with Aurora-A in colorectal cancer. Taken together, our data indicate that hnRNP Q1 is a novel trans-acting factor that binds to Aurora-A mRNA 5'-UTRs and regulates its translation, which increases cell proliferation and contributes to tumorigenesis in colorectal cancer.


Subject(s)
Aurora Kinase A/genetics , Carcinogenesis/genetics , Colorectal Neoplasms/genetics , Heterogeneous-Nuclear Ribonucleoproteins/genetics , Aurora Kinase A/metabolism , Cell Line, Tumor , Cell Proliferation/genetics , Colorectal Neoplasms/pathology , Female , Gene Expression Regulation, Neoplastic , Heterogeneous-Nuclear Ribonucleoproteins/metabolism , Humans , Male , RNA Recognition Motif Proteins , RNA, Messenger/genetics
16.
Int J Colorectal Dis ; 32(1): 155-157, 2017 Jan.
Article in English | MEDLINE | ID: mdl-27844203

ABSTRACT

INTRODUCTION: Tension-free mesh repair is a widely used hernioplasty technique. However, mesh migration is a severe complication that may induce colon inflammation or perforation and can occur several months to several years following hernioplasty. CASE REPORT: We present a case where mesh migrated into the sigmoid colon 12 years postoperation and was mistaken for a colon tumor.


Subject(s)
Colon, Sigmoid/pathology , Colonic Neoplasms/diagnosis , Herniorrhaphy/adverse effects , Surgical Mesh/adverse effects , Diagnosis, Differential , Humans , Male , Middle Aged , Ulcer/pathology
17.
Oncotarget ; 7(47): 76852-76866, 2016 Nov 22.
Article in English | MEDLINE | ID: mdl-27764771

ABSTRACT

MicorRNA-137 is silenced in human colorectal cancer tissues and colon polyps. Our study showed that the decreased expression of miR-137 is significantly different in various types of polyp which maintain different potentials to lead to CRC development. The expression of miR-137 gradually decreases during the process of colorectal carcinogenesis. Receiver operating characteristic curve (ROC) analysis indicates that the loss of miR-137 expression in colon polyps can serve as a biomarker to predict the predisposition of colorectal carcinogenesis. By cell model and xenograft animal model, the enforced expression of miR-137 in colorectal cancer cells can inhibit cell proliferation and tumor formation, induce G2/M arrest, and lead to apoptosis. The expression pattern of miR-137 and Aurora-A or PTGS2 is negatively correlated in human colorectal cancer tissues and colon polyps. Those effects induced by overexpressed miR-137 can be rescued by the overexpression of Aurora-A. In summary, our study suggests that the loss of miR-137 expression in colon polyps can serve as a biomarker to predict the tendency toward to CRC formation through the impaired inhibitory effect of Aurora-A. The investigation of the regulatory mechanism of miR-137-mediated Aurora-A inhibition may shed new light on the early prognosis of cancer therapy for CRC in the future.


Subject(s)
Aurora Kinase A/genetics , Colonic Polyps/genetics , Colorectal Neoplasms/genetics , Cyclooxygenase 2/genetics , DNA Methylation , MicroRNAs/genetics , Adult , Aged , Aged, 80 and over , Animals , Cell Line, Tumor , Cell Proliferation , Down-Regulation , Epigenesis, Genetic , Female , Gene Expression Regulation, Neoplastic , HCT116 Cells , Humans , Male , Mice , Middle Aged , Neoplasm Transplantation
18.
PLoS One ; 11(7): e0158844, 2016.
Article in English | MEDLINE | ID: mdl-27383761

ABSTRACT

Colorectal cancer is the most common form of cancer in the world, and the five-year survival rate is estimated to be almost 90% in the early stages. Therefore, the identification of potential biomarkers to assess the prognosis of early stage colorectal cancer patients is critical for further clinical treatment. Dysregulated tyrosine phosphorylation has been found in several diseases that play a significant regulator of signaling in cellular pathways. In this study, this strategy was used to characterize the tyrosine phosphoproteome of colorectal cell lines with different progression abilities (SW480 and SW620). We identified a total of 280 phosphotyrosine (pTyr) peptides comprising 287 pTyr sites from 261 proteins. Label-free quantitative analysis revealed the differential level of a total of 103 pTyr peptides between SW480 and SW620 cells. We showed that cyclin-dependent kinase I (CDK1) pTyr15 level in SW480 cells was 3.3-fold greater than in SW620 cells, and these data corresponded with the label-free mass spectrometry-based proteomic quantification analysis. High level CDK1 pTyr15 was associated with prolonged disease-free survival for stage II colorectal cancer patients (n = 79). Taken together, our results suggest that the CDK1 pTyr15 protein is a potential indicator of the progression of colorectal cancer.


Subject(s)
CDC2 Protein Kinase/metabolism , Colorectal Neoplasms/metabolism , Phosphoproteins/metabolism , Proteome/metabolism , Proteomics/methods , Biomarkers, Tumor/genetics , Biomarkers, Tumor/metabolism , Blotting, Western , Cell Line, Tumor , Colorectal Neoplasms/genetics , Colorectal Neoplasms/therapy , Female , Gene Expression Regulation, Neoplastic , Humans , Immunohistochemistry , Kaplan-Meier Estimate , Male , Neoplasm Staging , Phosphopeptides/metabolism , Phosphotyrosine/metabolism , Prognosis , Retrospective Studies
19.
J Formos Med Assoc ; 115(8): 609-18, 2016 Aug.
Article in English | MEDLINE | ID: mdl-27302557

ABSTRACT

BACKGROUND/PURPOSE: This study aims to examine the cost effectiveness of treating major cancers compared with other major illnesses in Taiwan. METHODS: We collected data on 395,330 patients with cancer, 125,277 patients with end-stage renal disease, and 50,481 patients under prolonged mechanical ventilation during 1998-2007. They were followed for 10-13 years to estimate lifetime survival functions using a semiparametric method. EuroQol five-dimension was used to measure the quality of life for 6189 cancer patients and 1401 patients with other illnesses. The mean utility values and healthcare costs reimbursed by the National Health Insurance were multiplied with the corresponding survival probabilities to estimate quality-adjusted life expectancies and lifetime costs, respectively. Data of 22,344 cancer patients under hospice care (considered as a comparison group) were used to conduct a cost-effectiveness analysis. Sensitivity analysis was conducted by assuming patients without treatment survived for 2 years with a quality of life value of 0.5. RESULTS: The costs of care for patients under prolonged mechanical ventilation and those with end-stage renal disease were US$41,780-53,708 per quality-adjusted life year (QALY) and US$18,222-18,465 per QALY, respectively, which are equivalent to 2.17-2.79 gross domestic product (GDP) per capita per QALY and 1.18-1.25 GDP per capita per QALY. The costs of care for the nine different cancers were less than 1 GDP per capita per QALY, with those of lung, esophagus, and liver cancers being the highest. Sensitivity analysis showed the same conclusion. Lifetime risks of six out of nine cancer sites show an increased trend. CONCLUSION: Cancer care in Taiwan seemed cost effective compared with that of other illnesses, but prevention is necessary to make the National Health Insurance more sustainable.


Subject(s)
Cost-Benefit Analysis , Health Expenditures , Neoplasms/economics , Adult , Aged , Aged, 80 and over , Female , Humans , Kidney Failure, Chronic/economics , Kidney Failure, Chronic/therapy , Male , Middle Aged , Neoplasms/classification , Neoplasms/therapy , Quality of Life , Quality-Adjusted Life Years , Registries , Respiration, Artificial/economics , Taiwan
20.
World J Surg ; 40(4): 895-905, 2016 Apr.
Article in English | MEDLINE | ID: mdl-26711638

ABSTRACT

Literature about the risk of secondary cancer after radiation therapy (RT) of prostate and rectal cancer reveals contradictory results. We conducted a meta-analysis to examine whether the RT induces secondary rectal or prostate cancer in patients, respectively, with prostate or rectal cancer. All studies published in Medline or Pubmed up to March 3, 2015, containing RT of primary rectal or prostate cancer, and providing risk estimates of secondary prostate or rectal cancer were considered as eligible. Relative risk (RR) and standardized incidence ratios (SIR) were calculated using the random-effects model. Twenty studies met the inclusion criteria. 12 of them were from the Surveillance, Epidemiology, and End Results (SEER) database. For prostate cancer patients, pooled adjusted RRs or SIRs did not show an effect on the risk of secondary rectal cancer. However, notwithstanding the limitations of SEER-based studies, the subgroup of prostate cancer patients receiving external beam radiation therapy (EBRT) showed an increased risk of rectal cancer. For rectal cancer patients, pooled adjusted RR of prostate cancer was 1.12 (95 % CI, 0.44-2.8) and SIR was 0.40 (95 % CI, 0.29-0.55). All studies included in the SIR analysis of rectal cancer were derived from the SEER data source. Based on current evidence, RT for prostate cancer patients had no effect on rectal cancer incidence, except for patients who received EBRT therapy. However, compared with the general population, RT for rectal cancer is associated with a decreased prostate cancer risk as found in SEER-based studies.


Subject(s)
Brachytherapy/statistics & numerical data , Neoplasms, Second Primary/epidemiology , Prostatic Neoplasms/radiotherapy , Rectal Neoplasms/radiotherapy , Humans , Incidence , Male , Proportional Hazards Models , Prostatic Neoplasms/epidemiology , Radiotherapy/statistics & numerical data , Rectal Neoplasms/epidemiology , Risk Factors
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