Background: Toll-like receptors (TLRs) play pivotal roles in host immune responses and have been suggested to be involved in the development of many infectious diseases. In this study, the mRNA expression levels of TLR2, TLR4, and TLR9 and their relationship with periodontopathic bacteria in periodontal tissue are examined. Furthermore, the mechanism of TLR induction by Porphyromonas gingivalis is investigated in human gingival fibroblasts (HGFs).
Methods: Gingival tissue and subgingival plaque samples were collected from 19 patients with chronic periodontitis (CP) and 16 control individuals without periodontitis. Gene expression levels in the tissues and in HGFs were analyzed by reverse transcription-polymerase chain reaction (RT-PCR). The numbers of periodontopathic bacteria were determined by quantitative real-time PCR.
Results: The expression levels of TLR2 and TLR9 were significantly higher in the tissues of patients with CP compared to the tissues of control individuals. The mRNA levels of TLR2 and TLR9, but not TLR4, were positively correlated with the number of P. gingivalis in subgingival plaque. P. gingivalis sonicated extract, P. gingivalis lipopolysaccharide, P. gingivalis DNA, and tumor necrosis factor-α(TNF-α) could significantly upregulate the mRNA expression of TLR2 in HGFs. Furthermore, P. gingivalis-mediated TLR2 expression was suppressed by TNF-α antibody.
Conclusions: This study suggests that P. gingivalis infection induces TLR2 and TLR9 upregulation in patients with CP. P. gingivalis-induced TLR2 expression in HGFs is partially dependent on TNF-α and may lead to sensitization of HGFs to bacterial components encountered in the periodontal microenvironment.
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http://dx.doi.org/10.1902/jop.2012.120362 | DOI Listing |
Blood
January 2025
IDIBAPS, Barcelona, Spain.
Previous studies have reported that chronic lymphocytic leukemia (CLL) shows a de novo chromatin activation pattern as compared to normal B cells. Here, we explored whether the level of chromatin activation is related to the clinical behavior of CLL. We identified that in some regulatory regions, increased de novo chromatin activation is linked to clinical progression whereas, in other regions, it is associated with an indolent course.
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January 2025
Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, United States.
Stemness-associated cell states are linked to chemotherapy resistance in AML. We uncovered a direct mechanistic link between expression of the stem cell transcription factor GATA2 and drug resistance. The GATA-binding protein 2 (GATA2) plays a central role in blood stem cell generation and maintenance.
View Article and Find Full Text PDFDiscov Oncol
January 2025
Department of Geriatric Respiratory and Critical Care Medicine, The First Affiliated Hospital of Anhui Medical University, Hefei, Anhui Province, China.
Aim: This study aimed to identify the genes associated with the development of lung adenocarcinoma (LUAD) and potential therapeutic targets.
Methods: Differentially expressed genes (DEGs) were identified by self-transcriptome sequencing of tumor tissues and paracancerous tissues resected during surgery and combined with The Cancer Genome Atlas (TCGA) data to screen for the genes associated with LUAD prognosis. The expression was validated at mRNA and protein levels, and the gene knockdown was used to examine the impact and underlying mechanisms on lung cancer cells.
Adv Exp Med Biol
January 2025
Department of Medical Biology, Istanbul Faculty of Medicine, Istanbul University, Istanbul, Turkey.
Among the mechanisms, cancer cells develop to elude immune system, immune regulation and the use of molecules that play important roles in immune escape stand out. One of these molecules, the human leukocyte antigen G (HLA-G), plays an important role in the maintenance of immune tolerance and contributes to the progression of cancer by exerting an immunosuppressive effect. By creating an immunosuppressive field in the microscopic environment of the tumor, the aberrant expression of HLA-G facilitates the evading of cancer cells from the immune system and contributes to the progression of the disease.
View Article and Find Full Text PDFRice (N Y)
January 2025
State Key Laboratory of Crop Gene Resources and Breeding, Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing, 100081, China.
Rice is highly sensitive to low temperatures, making cold stress a significant factor limiting its growth, especially during the bud bursting stage. To address this, an RIL population derived from a cross between cold-tolerant and cold-sensitive rice varieties was used to identify nine QTLs linked to cold tolerance under temperatures of 4 ℃, 5 °C, and 6 ℃ using a high-density genetic map. One candidate gene, LOC_Os07g44410, was identified through gene function annotation, haplotype analysis, and qRT-PCR, with two main haplotypes (Hap1 and Hap2) showing distinct phenotypic differences.
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