The Kruppel-like factor 5 (Klf5) regulates pluripotent stem cell self-renewal but its role in somatic stem cells is unknown. Klf5 deficient hematopoietic stem cells and progenitors (HSC/P) fail to engraft after transplantation. This HSC/P defect was associated with impaired bone marrow (BM) homing and lodging and decreased retention in BM. The Klf5/ HSC/P homing defect associated with decreased adhesion to fibronectin and expression of membrane-bound 1/2-integrins. In vivo inducible gain-of-function of Klf5 in HSC translated into increased HSC/P adhesion. The expression of Rab5 family members, mediators of 1/2-integrin recycling in the early endosome, was decreased in Klf5/ HSC/P. Klf5 binds directly to the promoter of Rab5a/b and overexpression of Rab5b rescued the expression of activated 1/2-integrins, adhesion and BM homing of Klf5/ HSC/P. Altogether, these data indicate that Klf5 is indispensable for adhesion, homing, lodging and retention of HSC/P in the BM through Rab5-dependent post-translational regulation of Beta1/Beta2 integrins.
Klf5 controls bone marrow homing of stem cells and progenitors through Rab5-mediated β1/β2-integrin trafficking.
Specimen part
View SamplesAlthough various mechanisms have been inferred for combinatorial actions of multiple carcinogens, these mechanisms have not been well demonstrated in experimental carcinogenesis models. We evaluated mammary carcinogenesis initiated by combined exposure to various doses of radiation and chemical carcinogens. Female rats at 7 weeks of age were -irradiated (0.22 Gy) and/or exposed to 1-methyl-1-nitrosourea (20 or 40 mg/kg, single intraperitoneal injection) or 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (40 mg/kg/day by gavage for 10 days) and were observed until 50 weeks of age. The incidence of mammary carcinoma increased steadily as a function of radiation dose in the absence of chemicals; mathematical analysis supported an additive increase when radiation was combined with a chemical carcinogen, irrespective of the chemical species and its dose. Hras mutations were characteristic of carcinomas that developed after chemical carcinogen treatments and were overrepresented in carcinomas induced by the combination of radiation and MNU (but not PhIP), indicating an interaction of radiation and MNU at the level of initiation. The expression profiles of seven classifier genes, previously shown to distinguish two classes of rat mammary carcinomas, categorized almost all examined carcinomas that developed after individual or combined treatments with radiation (1 Gy) and chemicals as belonging to a single class; more comprehensive screening using microarrays and a separate test sample set failed to identify differences in gene expression profiles among these carcinomas. These results suggest that a complex, multilevel interaction underlies the combinatorial action of radiation and chemical carcinogens in the experimental model.
Molecular characterization of cancer reveals interactions between ionizing radiation and chemicals on rat mammary carcinogenesis.
Specimen part
View SamplesAcquisition of a new strain of non-typeable Haemophilus influenzae (NTHi) is often associated with exacerbation of chronic obstructive pulmonary disease (COPD). We have previously reported that COPD patients who are homozygous null for SIGLEC14 gene is less susceptible to COPD exacerbation than those who have wild-type allele with functional SIGLEC14 gene.
Association of serum interleukin-27 with the exacerbation of chronic obstructive pulmonary disease.
Cell line
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Identification of NUCKS1 as a colorectal cancer prognostic marker through integrated expression and copy number analysis.
Specimen part
View SamplesPurpose: This study aimed to identify a novel biomarker or a target of treatment for colorectal cancer (CRC).
Clinical significance of osteoprotegerin expression in human colorectal cancer.
Specimen part
View SamplesPurpose: The purpose of this study is to identify a novel biomarker related with distant metastases of colorectal cancer (CRC).
Identification of NUCKS1 as a colorectal cancer prognostic marker through integrated expression and copy number analysis.
Specimen part
View SamplesUnearthing of silenced genes in colorectal cancer (CRC) is of great importance. We employed oligonucleotide microarray to find changes in global gene expression of five CRC cell lines. These were analyzed before and after treatment with the 5-aza-2'-Deoxycitidine. Expression of the responding genes was integrated with gene expression profiling generated by microarray analysis of matched colorectal tissue samples. Selected candidates were subjected to methylation-specific PCR (MSP) and real-time quantitative reverse transcription-PCR using CRC cell lines and paired tumor and normal samples from CRC patients. Sixty eight genes were re-expressed after 5-aza-2'-Deoxycitidine treatment and over-expressed in normal colorectal mucosa, including genes that were known to be methylated in CRC. After applying study selection criteria, we identified 16 potential genes. Two candidates were selected (ASPP1 and SCARA5). Among 15 CRC cell lines, methylation was identified in SCARA5 (20%). The methylation status of SCARA5 was subsequently investigated in 23 paired colorectal tissue samples; methylation was detected in 17%, respectively. Observed promoter methylation showed a tendency towards methylation in tumor-derived samples, in SCARA5 gene. Significant down expression of SCARA5 mRNA was observed in CRC cell lines and tumor tissues compared to adjacent normal tissues (P < 0.001 and P = 0.001, respectively). The use of genome-wide screening led to the identification of a group of candidate genes. Among them, SCARA5 was methylated and markedly down-regulated in CRC. SCARA5 gene may have a role in CRC tumorigenesis.
Screening for epigenetically masked genes in colorectal cancer Using 5-Aza-2'-deoxycytidine, microarray and gene expression profile.
Specimen part
View SamplesSpinocerebellar ataxia type 6 (SCA6) is a dominantly inherited neurodegenerative disease caused by an expansion of a CAG repeat encoding a polyglutamine (PolyQ) tract in the Cav2.1 voltage-gated calcium channel. Pathologically, it is characterized by selective degeneration of cerebellar Purkinje cells (PCs), which are a common target for PolyQ-induced toxicity among several different SCAs. Mutant Cav2.1 confers toxicity mainly through a toxic gain-of-function mechanism, but subcellular site of expanded Cav2.1 toxicity is controversial and it remains elusive whether SCA6 shares pathogenic cascades with other SCAs. To gain insight into these problems, we studied the cerebellar gene expression patterns of young Sca6 MPI 118Q/118Q knockin (KI) mice, which express mutant Cav2.1 from endogenous locus and faithfully models human SCA6. Comparison of transcriptional changes with those of Sca1 154Q/2Q mice, a faithful KI mouse model of SCA1, revealed that transcriptional signatures in the MPI 118Q/118Q were distinct from those of Sca1 154Q/2Q. Examination of temporal profiles of candidate genes showed that upregulation of those associated with microglial activation was initiated before PC degeneration was apparent and augmented as the disease progressed. Histological analysis of the MPI 118Q/118Q cerebellum confirmed the presence of Iba-1 positive activated microglia. Moreover, predominance of M1-like pro-inflammatory microglia was observed and was concomitant with the increased expression of pro-inflammatory cytokines. These results suggest that the unique transcriptional response, which highlights upregulation of neuroinflammatory genes possibly associated with lysosomal involvement, may play a pivotal role in the pathogenesis. Modulation of innate immune system could pave the way for slowing the progression of SCA6.
Loss of MyD88 alters neuroinflammatory response and attenuates early Purkinje cell loss in a spinocerebellar ataxia type 6 mouse model.
Specimen part
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Prognostic significance of Traf2- and Nck- interacting kinase (TNIK) in colorectal cancer.
Specimen part
View SamplesBackground: The potential of expression profiling using microarray analysis as a tool to predict the prognosis for different types of cancer has been realized. This study aimed to identify a novel biomarker for colorectal cancer (CRC). Methods: The expression profiles of cancer cells in 152 patients with stage I-III CRC were examined using microarray analysis. High expression in CRC cells, especially in patients with distant recurrences, was a prerequisite to select candidate genes. Thus, we identified eleven candidate genes, and selected Traf2- and Nck-interacting kinase (TNIK), which was known to be associated with progression in CRC through Wnt signaling pathways. We analyzed the protein expression of TNIK using immunohistochemistry (IHC) and investigated the relationship between protein expression and patient characteristics in 220 stage I-III CRC patients. Results: Relapse-free survival was significantly worse in the TNIK high expression group than in the TNIK low expression group in stage II (p = 0.028) and stage III (p = 0.006) patients. In multivariate analysis, high TNIK expression was identified as a significant independent risk factor of distant recurrence in stage III patients. Conclusion: This study is the first to demonstrate the prognostic significance of intratumoral TNIK protein expression in clinical tissue samples of CRC, in that high expression of TNIK protein in primary tumors was associated with distant recurrence in stage II and III CRC patients. This TNIK IHC study might contribute to practical decision-making in the treatment of these patients.
Prognostic significance of Traf2- and Nck- interacting kinase (TNIK) in colorectal cancer.
Specimen part
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