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1.
Vet Res Commun ; 2024 Apr 03.
Article in English | MEDLINE | ID: mdl-38565798

ABSTRACT

Cryptosporidium spp., Enterocytozoon bieneusi, and Giardia duodenalis are common intestinal pathogens that infect humans and animals. To date, research regarding these three protozoa in the Ningxia Hui Autonomous Region (Ningxia) has mostly been limited to a single pathogen, and comprehensive data on mixed infections are unavailable. This study aimed to evaluate the zoonotic potential of these three protozoa. In this study, small subunit ribosomal RNA (SSU rRNA) and 60 kDa glycoprotein (gp60) genes of Cryptosporidium; internal transcribed spacer (ITS) gene of E. bieneusi; and SSU rRNA, glutamate dehydrogenase (gdh), triosephosphate isomerase (tpi), and beta-giardin (bg) genes of G. duodenalis were examined. DNA extraction, polymerase chain reaction, and sequence analysis were performed on fecal samples collected from 320 dairy cattle at three intensive dairy farms in Ningxia in 2021 to determine the prevalence and genetic characteristics of these three protozoa. The findings revealed that 61.56% (197/320) of the samples were infected with at least one protozoan. The overall prevalence of Cryptosporidium was 19.38% (62/320), E. bieneusi was 41.56% (133/320), and G. duodenalis was 29.38% (94/320). This study identified four Cryptosporidium species (C. bovis, C. andersoni, C. ryanae, and C. parvum) and the presence of mixed infections with two or three Cryptosporidium species. C. bovis was the dominant species in this study, while the dominant C. parvum subtypes were IIdA15G1 and IIdA20G1. The genotypes of E. bieneusis were J, BEB4, and I alongside the novel genotypes NX1-NX8, all belonging to group 2, with genotype J being dominant. G. duodenalis assemblages were identified as assemblages E, A, and B, and a mixed infection involving assemblages A + E was identified, with assemblage E being the dominant one. Concurrently, 11 isolates formed 10 different assemblage E multilocus genotypes (MLGs) and 1 assemblage A MLG and assemblage E MLGs formed 5 subgroups. To the best of our knowledge, this is the first report on mixed infection with two or three Cryptosporidium species in cattle in Ningxia and on the presence of the C. parvum subtype IIdA20G1 in this part of China. This study also discovered nine genotypes of E. bieneusis and novel features of G. duodenalis assemblages in Ningxia. This study indicates that dairy cattle in this region may play a significant role in the zoonotic transmission of Cryptosporidium spp., E. bieneusi, and G. duodenalis.

2.
BMC Vet Res ; 19(1): 134, 2023 Aug 25.
Article in English | MEDLINE | ID: mdl-37626358

ABSTRACT

BACKGROUND: Cryptosporidium is a gastrointestinal protozoan that widely exists in nature, it is an established zoonotic pathogen. Infected cattle are considered to be associated with cryptosporidiosis outbreaks in humans. In the present study, we aimed to assess the prevalence and species distribution of Cryptosporidium in dairy cattle in Central Inner Mongolia. METHODS: We focused on the small subunit ribosomal RNA gene (SSU rRNA) of Cryptosporidium and 60-kDa glycoprotein gene (gp60) of Cryptosporidium parvum. We collected 505 dairy cattle manure samples from 6 sampling sites in Inner Mongolia in 2021; the samples were divided into 4 groups based on age. DNA extraction, polymerase chain reaction (PCR), sequence analysis, and restriction fragment length polymorphism (RFLP) using SspI and MboII restriction endonucleases were performed. RFLP analysis was performed to determine the prevalence and species distribution of Cryptosporidium. RESULTS: SSU rRNA PCR revealed that the overall prevalence of Cryptosporidium infection was 29.90% (151/505), with a prevalence of 37.67% (55/146) and 26.74% (96/359) in diarrheal and nondiarrheal samples, respectively; these differences were significant. The overall prevalence of Cryptosporidium infection at the 6 sampling sites ranged from 0 to 47.06% and that among the 4 age groups ranged from 18.50 to 43.81%. SSU rRNA sequence analysis and RFLP analysis revealed the presence of 4 Cryptosporidium species, namely, C. bovis (44.37%), C. andersoni (35.10%), C. ryanae (21.85%), and C. parvum (11.92%), along with a mixed infection involving two or three Cryptosporidium species. Cryptosporidium bovis or C. andersoni was the most common cause of infection in the four age groups. The subtype of C. parvum was successfully identified as IIdA via gp60 analysis; all isolates were identified as the subtype IIdA19G1. CONCLUSIONS: To the best of our knowledge, this is the first report of dairy cattle infected with four Cryptosporidium species in Inner Mongolia, China, along with a mixed infection involving two or three Cryptosporidium species, with C. bovis and C. andersoni as the dominant species. Moreover, this is the first study to identify C. parvum subtype IIdA19G1 in cattle in Inner Mongolia. Our study findings provide detailed information on molecular epidemiological investigation of bovine cryptosporidiosis in Inner Mongolia, suggesting that dairy cattle in this region are at risk of transmitting cryptosporidiosis to humans.


Subject(s)
Cattle Diseases , Coinfection , Cryptosporidiosis , Cryptosporidium , Humans , Animals , Cattle , Cryptosporidium/genetics , Cryptosporidiosis/epidemiology , Coinfection/veterinary , Prevalence , China/epidemiology , RNA, Ribosomal , Cattle Diseases/epidemiology
3.
Sci Rep ; 13(1): 13960, 2023 08 26.
Article in English | MEDLINE | ID: mdl-37634027

ABSTRACT

Giardia duodenalis is a gastrointestinal protozoan ubiquitous in nature. It is a confirmed zoonotic pathogen, and cattle are considered a source of giardiasis outbreaks in humans. This study aimed to evaluate the prevalence and multilocus genotype (MLG) of G. duodenalis in dairy cattle in Central Inner Mongolia. This study was based on the small subunit ribosomal RNA (SSU rRNA), glutamate dehydrogenase (gdh), triosephosphate isomerase (tpi), and beta-giardin (bg) genes of G. duodenalis. DNA extraction, polymerase chain reaction (PCR), and sequence analysis were performed on 505 dairy cattle fecal samples collected in 2021 from six sampling sites and four age groups in Central Inner Mongolia to determine the prevalence and MLG distribution of G. duodenalis. The PCR results of SSU rRNA revealed that the overall prevalence of G. duodenalis was 29.5% (149/505) and that the overall prevalence of the diarrhea and nondiarrhea samples was 31.5% (46/146) and 28.5% (103/359), respectively; the difference was not significant (p > 0.05). SSU rRNA sequence analysis revealed that G. duodenalis assemblage E (91.1%, 133/146) was primarily detected and that assemblage A (8.9%, 13/146) was detected in 13 samples. The G. duodenalis-positive samples were PCR amplified and sequenced for gdh, tpi, and bg, from which 38, 47, and 70 amplified sequences were obtained, respectively. A combination of G. duodenalis assemblages A and E were detected in seven samples. Multilocus genotyping yielded 25 different assemblage E MLGs, which formed six subgroups. To the best of our knowledge, this is the first report regarding G. duodenalis infection in dairy cattle in Inner Mongolia, China. This study revealed that Inner Mongolian cattle pose a risk of giardiasis transmission to humans and that the distribution of local cattle G. duodenalis assemblage E MLGs is diverse. The findings of this study can bridge the knowledge gap in the molecular epidemiological investigation of giardiasis in Central Inner Mongolia.


Subject(s)
Giardia lamblia , Giardiasis , Animals , Cattle , China/epidemiology , Giardia lamblia/genetics , Giardiasis/epidemiology , Giardiasis/veterinary , Glutamate Dehydrogenase/genetics , Prevalence , Protozoan Proteins/genetics , RNA, Ribosomal/genetics , Triose-Phosphate Isomerase/genetics
4.
Phytomedicine ; 112: 154715, 2023 Apr.
Article in English | MEDLINE | ID: mdl-36821999

ABSTRACT

BACKGROUND: Hepatocellular carcinoma (HCC) is a leading cause of cancer-associated mortality in the world. However, the anticancer effects of aucubin against HCC have yet to be reported. Cisplatin often decreased CD8+ tumor-infiltrating lymphocytes in the tumor microenvironment through increasing programmed death-ligand 1 (PD-L1) expression, which seriously affected the prognostic effect of cisplatin in the treatment of patients with HCC. Therefore, it is necessary to identify a novel therapeutic avenue to increase the sensitivity of cisplatin against HCC. PURPOSE: This study aims to evaluate the anti-tumor effect of aucubin on HCC, and also to reveal the synergistic effects and mechanism of aucubin and cisplatin against HCC. STUDY DESIGN AND METHODS: An H22 xenograft mouse model was established for the in vivo experiments. Cancer cell proliferation was detected by MTT assay. RT-qPCR was performed to analyze CD274 mRNA expression in vitro. Western blotting was employed to determine the expression levels of the PD-L1, p-Akt, Akt, p-ß-catenin, and ß-catenin in vitro. Immunofluorescence was carried out to examine ß-catenin nuclear accumulation in HCC cells. Immunohistochemistry was used to detect tumoral PD-L1 and CD8α expression in xenograft mouse model. RESULTS: Aucubin inhibits tumor growth in a xenograft HCC mouse model, but did not affect HCC cell viability in vitro. Aucubin treatment significantly inhibited PD-L1 expression through inactivating Akt/ß-catenin signaling pathway in HCC cells. Overexpression of PD-L1 dramatically reversed aucubin-mediated tumoral CD8+ T cell infiltration and alleviated the antitumor activity of aucubin in xenograft mouse model. Moreover, Cisplatin could induce the expression of PD-L1 through the activation of the Akt/ß-catenin signaling pathway in HCC cells, which can be blocked by aucubin in vitro. In xenograft mouse model, cisplatin treatment induced PD-L1 expression and alleviated the infiltration of CD8+ T lymphocytes in the tumor microenvironment. Aucubin not only abrogated cisplatin-induced PD-L1 expression but also enhanced the antitumor efficacy of cisplatin in a mouse xenograft model of HCC. CONCLUSION: Aucubin exerts antitumor activity against HCC and also enhances the antitumor activity of cisplatin by suppressing the Akt/ß-catenin/PD-L1 axis.


Subject(s)
Carcinoma, Hepatocellular , Liver Neoplasms , Humans , Animals , Mice , Carcinoma, Hepatocellular/metabolism , Cisplatin/pharmacology , Cisplatin/therapeutic use , B7-H1 Antigen/metabolism , Liver Neoplasms/metabolism , beta Catenin/metabolism , Proto-Oncogene Proteins c-akt , Cell Line, Tumor , Tumor Microenvironment
5.
Front Vet Sci ; 9: 1021426, 2022.
Article in English | MEDLINE | ID: mdl-36311671

ABSTRACT

Ticks were identified as arthropods that are pathogenic vectors. Dermacentor nuttalli is one of the dominant tick species in Inner Mongolia, and it carries and transmits a wide range of pathogenic microorganisms. However, at present, only the detection of D. nuttalli adult ticks and D. nuttalli different developmental stages carrying one specific pathogen, or the next-generation sequencing of D. nuttalli adult ticks were available. In this study, we investigated the microbial community structures of D. nuttalli in different growth stages under laboratory artificial feeding conditions. Total DNA was extracted from seven growth stages (female adult ticks, eggs, larval ticks, engorged larval ticks, nymphal ticks, engorged nymphal ticks, and second-generation adult ticks) obtained from laboratory artificial feeding of engorged D. nuttalli female ticks in Inner Mongolia. Then, the 16S rDNA V3-V4 hypervariable region was amplified to construct an Illumina PE250 library. Finally, 16S rRNA sequencing was performed on Illumina Novaseq 6000 platform. The sequencing data were analyzed using molecular biology software and platforms. The Illumina PE250 sequencing results showed that the egg stage had the highest diversity and number of species (28.74%, 98/341), while the engorged nymph stage had the lowest diversity and number of species (9.72%, 21/216). A total of 387 genera of 22 phyla were annotated in D. nuttalli, with 9 phyla and 57 genera found throughout all 7 growth stages. The dominant phylum was Proteobacteria; the dominant genera were Arsenophonus and Rickettsia; and the genera with the highest relative abundance in the 7 growth stages were Pseudomonas, Paenalcaligenes, Arsenophonus, Arsenophonus, Pseudomonas, Arsenophonus, and Rickettsia, respectively. Among the 23 exact species annotated, Brucella melitensis exhibits pathogeny that poses a serious threat to humans and animals. In this study, the microbial community composition at different growth stages of D. nuttalli was comprehensively analyzed for the first time.

6.
Front Microbiol ; 13: 988136, 2022.
Article in English | MEDLINE | ID: mdl-36147838

ABSTRACT

Melophagus ovinus (sheep ked) is one of the common ectoparasites in sheep. In addition to causing direct damage to the host through biting and sucking blood, sheep ked is a potential vector of helminths, protozoa, bacteria, and viruses. Sheep M. ovinus samples from three regions in Tibet were selected for DNA extraction. The 16S rDNA V3-V4 hypervariable region was amplified, after genomic DNA fragmentation, Illumina Hiseq libraries were constructed. The 16S rRNA sequencing and viral metagenomics sequencing were separately conducted on the Illumina Novaseq 6000 platform and molecular biology software and platforms were employed to analyze the sequencing data. Illumina PE250 sequencing results demonstrated that the dominant bacteria phylum in M. ovinus from Tibet, China was Proteobacteria, where 29 bacteria genera were annotated. The dominant bacterial genera were Bartonella, Wolbachia, and Arsenophonus; Bartonella chomelii, Wolbachia spp., and Arsenophonus spp. were the dominant bacterial species in M. ovinus from Tibet, China. We also detected Kluyvera intermedia, Corynebacterium maris DSM 45190, Planomicrobium okeanokoites, and Rhodococcus erythropolis, of which the relative abundance of Kluyvera intermedia was high. Illumina Hiseq sequencing results demonstrated that 4 virus orders were detected in M. ovinus from Tibet, China, and 3 samples were annotated into 29 families, 30 families, and 28 families of viruses, respectively. Virus families related to vertebrates and insects mainly included Mimiviridae, Marseilleviridae, Poxviridae, Ascoviridae, Iridoviridae, Baculoviridae, Hytrosaviridae, Nudiviridae, Polydnaviridae, Adomaviridae, Asfarviridae, Hepeviridae, Herpesviridae, and Retroviridae; at the species level, the relative abundance of Tupanvirus_soda_lake, Klosneuvirus_KNV1, and Indivirus_ILV1 was higher. African swine fever virus and many poxviruses from the family Poxviridae were detected, albeit their relative abundance was low. The dominant bacterial phylum of M. ovinus from Tibet, China was Proteobacteria, and the dominant bacterial genera were Bartonella, Wolbachia, and Arsenophonus, where 23 out of 29 annotated bacteria genera were first reported in M. ovinus. Kluyvera intermedia, Corynebacterium maris DSM 45190, Planomicrobium okeanokoites, and Rhodococcus erythropolis were detected for the first time. All DNA viruses detected in this study have been reported in M. ovinus for the first time.

7.
Oncogenesis ; 11(1): 3, 2022 Jan 17.
Article in English | MEDLINE | ID: mdl-35039478

ABSTRACT

Epididymal protein 3A (EDDM3A) is a protein involved in sperm maturation. It has been demonstrated that EDDM3A expression is upregulated and promotes cell proliferation in non-small cell lung cancer (NSCLC). However, the role of EDDM3A in other types of human cancers, including gastric cancer (GC), is still unexplored. Here, we show that the expression of EDDM3A is significantly upregulated in gastric cancer (GC) tissues and its upregulation correlates with poorer survival in patients with gastric cancer. Knockdown of EDDM3A inhibited growth and metastasis of GC cells, whereas overexpression of EDDM3A exhibited the opposite effect. Mechanistically, enhanced aerobic glycolysis mediated by upregulation of HIF-1α and subsequently increased target glycolytic genes and decreased mitochondrial biogenesis was found to contribute to the promotion of tumor growth and metastasis by EDDM3A in GC cells. Additionally, upregulation of EDDM3A in GC is at least partially mediated by downregulation of miR-618. In conclusion, elevated EDDM3A plays a pivotal oncogenic role in gastric carcinogenesis, suggesting it as a potential therapeutic target for treatment of GC.

8.
PLoS One ; 16(9): e0256628, 2021.
Article in English | MEDLINE | ID: mdl-34492040

ABSTRACT

Paratuberculosis a contagious and chronic disease in domestic and wild ruminants, is caused by Mycobacterium avium subspecies paratuberculosis (MAP). Typical clinical signs include intractable diarrhea, progressive emaciation, proliferative enteropathy, and mesenteric lymphadenitis. Paratuberculosis is endemic to many parts of the world and responsible for considerable economic losses. In this study, different types of paratuberculosis and MAP in sheep and goats were investigated in Inner Mongolia, a northern province in China contiguous with two countries and eight other provinces. A total of 4434 serum samples were collected from six cities in the western, central, and eastern regions of Inner Mongolia and analyzed using the ELISA test. In addition, tissue samples were collected from seven animals that were suspected to be infected with MAP. Finally, these tissues samples were analyzed by histopathological examination followed by polymerase chain reaction (PCR), IS1311 PCR-restriction enzyme analysis (PCR-REA), and a sequence analysis of five genes. Among all 4434 ruminant serum samples collected from the six cities in the western, central, and eastern regions of Inner Mongolia, 7.60% (337/4434) measured positive for the MAP antibody. The proportions of positive MAP antibody results for serum samples collected in the western, central, and eastern regions were 5.10% (105/2058), 6.63% (85/1282), and 13.44% (147/1094), respectively. For the seven suspected infected animals selected from the herd with the highest rate of positivity, the gross pathology and histopathology of the necropsied animals were found to be consistent with the pathological features of paratuberculosis. The PCR analysis further confirmed the diagnosis of paratuberculosis. The rest of the results demonstrated that herds of sheep and goats in Inner Mongolia were infected with both MAP type II and type III. To the best of our knowledge, this is the first study of the two subtypes of MAP strains in sheep and goats in Inner Mongolia.


Subject(s)
Goat Diseases/microbiology , Mycobacterium avium/isolation & purification , Paratuberculosis/microbiology , Sheep Diseases/microbiology , Animals , China , Enzyme-Linked Immunosorbent Assay/methods , Genotype , Goat Diseases/blood , Goats/blood , Goats/microbiology , Mycobacterium avium/pathogenicity , Paratuberculosis/blood , Serology/methods , Sheep/blood , Sheep/microbiology , Sheep Diseases/blood
9.
Cell Biol Int ; 45(12): 2521-2533, 2021 Dec.
Article in English | MEDLINE | ID: mdl-34486197

ABSTRACT

Cisplatin has been reported to promote the expression of programmed cell death ligand-1 (PD-L1) in some cancer cells. However, the underlying mechanism through which PD-L1 is transcriptionally regulated by cisplatin in hepatocellular carcinoma (HCC) cells remains largely unknown. In the present study, we found that the expression of hepatocyte growth factor (HGF), p-Akt, p-ERK, and PD-L1 was increased in cisplatin-treated SNU-368 and SNU-739 cells. HGF stimulation also increased PD-L1 expression in these cells. Moreover, Inhibition of HGF/c-MET, PI3K/Akt, and MEK/ERK signaling pathways can dramatically block cisplatin or HGF-induced PD-L1 expression in SNU-368 and SNU-739 cells. In vivo, combination PHA665752 with cisplatin significantly reduced tumor weight with increased infiltration of CD8+ T cells in the tumor. Taken together, our study suggested that HGF/c-Met axis-induced the activation of PI3K/Akt and MEK/ERK pathways contributes to cisplatin-mediated PD-L1 expression. These findings may provide an alternative avenue for the treatment of HCC.


Subject(s)
B7-H1 Antigen/metabolism , Carcinoma, Hepatocellular/drug therapy , Carcinoma, Hepatocellular/metabolism , Cisplatin/pharmacology , Hepatocyte Growth Factor/metabolism , Liver Neoplasms/drug therapy , Liver Neoplasms/metabolism , Proto-Oncogene Proteins c-met/metabolism , Animals , CD8-Positive T-Lymphocytes/drug effects , CD8-Positive T-Lymphocytes/metabolism , Cell Line, Tumor , Humans , MAP Kinase Signaling System/drug effects , Male , Mice , Mice, Inbred BALB C , Phosphatidylinositol 3-Kinases/metabolism , Proto-Oncogene Proteins c-akt/metabolism , Signal Transduction/drug effects
10.
Hum Exp Toxicol ; 40(12_suppl): S187-S195, 2021 Dec.
Article in English | MEDLINE | ID: mdl-34372727

ABSTRACT

Background: Several recent studies have suggested that the long non-coding RNA (lncRNA) DSCAM-AS1 (Down syndrome cell adhesion molecule - anti-sense 1) is aberrantly expressed in many malignancies. Purpose: In this study, we aimed to explore the the role of DSCAM-AS1 in gastric carcinoma. Research Design: Expression of DSCAM-AS1 mRNA, miR-204, and TPT1 (Tumor Protein, Translationally-Controlled 1) were detected using quantitative real-time polymerase chain reaction (qRT-PCR). Proliferation and apoptosis of GC cells were determined using the CCK-8 cell counting assay and flow cytometry. The rate of cell migration and invasion was determined using a transwell assay. The relationships between DSCAM-AS1, miR-204, and TPT1 were predicted and confirmed using a dual-luciferase reporter assay. Expression of TPT1 protein was quantified by Western blot. Results: In this study, we found that DSCAM-AS1 was significantly overexpressed in GC tissues and cell lines. Functional experiments indicated that GC cells with DSCAM-AS1 silencing exhibited a dynamic reduction in proliferation and migration. We identified miR-204 as a target of DSCAM-AS1 and found that it targeted TPT1 in GC cells, which further led to decreased expression of miR-204 in GC tissues and cell lines. A rescue assay revealed that knocked-down DSCAM-AS1 hindered GC progression, which was reversed upon miR-204 downregulation or TPT1 overexpression. Conclusion: We conclude that DSCAM-AS1 is expressed as a tumor oncogene in GC progression, modulated via the miR-204/TPT1 axis. These findings indicate the potential of DSCAM-AS1 as a therapeutic target for GC prevention.


Subject(s)
Cell Adhesion Molecules/genetics , Cell Adhesion/genetics , Cell Movement/genetics , Cell Proliferation/genetics , Down Syndrome/genetics , MicroRNAs/metabolism , RNA, Long Noncoding/genetics , Stomach Neoplasms/pathology , Tumor Protein, Translationally-Controlled 1/metabolism , Animals , Cell Line , Cell Line, Tumor , Down Syndrome/pathology , Humans , Mice , Mice, Inbred BALB C , Mice, Nude
12.
Cancer Sci ; 112(2): 679-690, 2021 Feb.
Article in English | MEDLINE | ID: mdl-33164305

ABSTRACT

High-mobility group protein A2 (HMGA2) is highly expressed in hepatocellular carcinoma (HCC) cells and contributes to tumor metastasis and poor patient survival. However, the molecular mechanism through which HMGA2 is transcriptionally regulated in HCC cells remains largely unclear. Here, we showed that the expression HMGA2 was upregulated in HCC, and that elevated HMGA2 could promote tumor metastasis. Incubation of HCC cells with epidermal growth factor (EGF) could promote the expression of HMGA2 mRNA and protein. Mechanistic studies suggested that EGF can phosphorylate p300 at Ser1834 residue through the PI3K/Akt signaling pathway in HCC cells. Knockdown of p300 can reverse EGF-induced HMGA2 expression and histone H3-K9 acetylation, whereas a phosphorylation-mimic p300 S1834D mutant can stimulate HMGA2 expression as well as H3-K9 acetylation in HCC cells. Furthermore, we identified that p300-mediated H3-K9 acetylation participates in EGF-induced HMGA2 expression in HCC. In addition, the levels of H3-K9 acetylation positively correlated with the expression levels of HMGA2 in a chemically induced HCC model in rats and human HCC specimens.


Subject(s)
Carcinoma, Hepatocellular/pathology , Gene Expression Regulation, Neoplastic/physiology , HMGA2 Protein/biosynthesis , Histones/metabolism , Liver Neoplasms/pathology , Acetylation , Animals , Carcinoma, Hepatocellular/metabolism , ErbB Receptors/metabolism , Humans , Liver Neoplasms/metabolism , Male , Mice , Mice, Inbred BALB C , Mice, Nude , Rats , Rats, Sprague-Dawley , Transcription, Genetic , p300-CBP Transcription Factors/metabolism
13.
Front Pharmacol ; 11: 577108, 2020.
Article in English | MEDLINE | ID: mdl-33324209

ABSTRACT

High expression of programmed death-ligand-1 (PD-L1) in hepatocellular carcinoma (HCC) cells usually inhibits the proliferation and functions of T cells, leading to immune suppression in tumor microenvironment. However, very little has been described regarding the mechanism of PD-L1 overexpression in HCC cells. In the present study, we found epidermal growth factor (EGF) stimulation promoted the expression of PD-L1 mRNA and protein in HCC cells. Inhibition of epidermal growth factor receptor (EGFR) could reverse EGF-induced the expression of PD-L1 mRNA and protein. Subsequently, we also observed that the phosphorylation level of Pyruvate kinase isoform M2 (PKM2) at Ser37 site was also increased in response to EGF stimulation. Expression of a phosphorylation-mimic PKM2 S37D mutant stimulated PD-L1 expression as well as H3-Thr11 phosphorylation in HCC cells, while inhibition of PKM2 significantly blocked EGF-induced PD-L1 expression and H3-Thr11 phosphorylation. Furthermore, mutation of Thr11 of histone H3 into alanine abrogated EGF-induced mRNA and protein expression of PD-L1, Chromatin immunoprecipitation (ChIP) assay also suggested that EGF treatment resulted in enhanced H3-Thr11 phosphorylation at the PD-L1 promoter. In a diethylnitrosamine (DEN)-induced rat model of HCC, we found that the expression of phosphorylated EGFR, PKM2 nuclear expression, H3-Thr11 phosphorylation as well as PD-L1 mRNA and protein was higher in the livers than that in normal rat livers. Taken together, our study suggested that PKM2-dependent histone H3-Thr11 phosphorylation was crucial for EGF-induced PD-L1 expression at transcriptional level in HCC. These findings may provide an alternative target for the treatment of hepatocellular carcinoma.

14.
Sci Signal ; 13(657)2020 11 10.
Article in English | MEDLINE | ID: mdl-33172955

ABSTRACT

The protein Dickkopf-1 (DKK1) is frequently overexpressed at the transcript level in hepatocellular carcinoma (HCC) and promotes metastatic progression through the induction of ß-catenin, a Wnt signaling effector. We investigated how DKK1 expression is induced in HCC and found that activation of the epidermal growth factor receptor (EGFR) promoted parallel MEK-ERK and PI3K-Akt pathway signaling that converged to epigenetically stimulate DKK1 transcription. In HCC cell lines stimulated with EGF, EGFR-activated ERK phosphorylated the kinase PKM2 at Ser37, which promoted its nuclear translocation. Also in these cells, EGFR-activated Akt phosphorylated the acetyltransferase p300 at Ser1834 Subsequently, PKM2 and p300 mediated the phosphorylation and acetylation, respectively, of histone H3 at the DKK1 promoter, which synergistically enhanced DKK1 transcription. The mechanism was supported with mutational analyses in cells and in a chemically induced HCC model in rats. The findings suggest that dual inhibition of the MEK and PI3K pathways might suppress the expression of DKK1 and, consequently, tumor metastasis in patients with HCC.


Subject(s)
Carcinoma, Hepatocellular/metabolism , Epidermal Growth Factor/metabolism , Histones/metabolism , Intercellular Signaling Peptides and Proteins/metabolism , Liver Neoplasms/metabolism , MAP Kinase Signaling System , Neoplasm Proteins/metabolism , Transcription, Genetic , Acetylation , Animals , Carcinoma, Hepatocellular/genetics , Cell Line , Epidermal Growth Factor/genetics , Intercellular Signaling Peptides and Proteins/genetics , Liver Neoplasms/genetics , Male , Mice , Mice, Inbred BALB C , Mice, Nude , Neoplasm Proteins/genetics , Phosphorylation , Rats , Rats, Sprague-Dawley
15.
Exp Neurol ; 334: 113482, 2020 12.
Article in English | MEDLINE | ID: mdl-32979370

ABSTRACT

Wnt5b, a member of Wnt family, plays multiple roles in tumor progression and metastasis. However, whether Wnt5b contributes to the sensitization of dorsal root ganglia (DRG) neurons and pathogenesis of bone cancer pain still remains unclear. Here, we found that the protein expression of Wnt5b and its atypical tyrosine protein kinase receptor Ryk was upregulated in ipsilateral DRGs in tumor-bearing mice. Application of Wnt5b evoked an increased discharge frequency in isolated DRG neurons and pain hypersensitivity in naïve mice which were almost completely prevented by anti-Ryk antibody. Moreover, intrathecal injection of anti-Ryk antibody to tumor-bearing mice significantly inhibited bone cancer-induced mechanic allodynia and thermal hyperalgesia. Subsequently, we also demonstrated that application of Wnt5b to cultured DRG neurons could enhance membrane P2X3 receptors and α,ß-meATP-induced currents. Intrathecal injection of calmodulin-dependent protein kinase II (CaMKII) inhibitor KN93 or P2X3 receptors antagonist A317491 almost completely abolished Wnt5b-induced mechanical allodynia and thermal hyperalgesia in mice. Meanwhile, pretreatment with anti-Ryk antibody or CaMKII inhibitor KN93 can attenuate bone-cancer induced the upregulation of P2X3 membrane protein as well as pain hypersensitivity. These findings suggested that Wnt5b/Ryk promoted the trafficking of P2X3 receptors to the membrane via the activation of CaMKII in primary sensory neurons, resulting in peripheral sensitization and bone cancer-induced pain. Our results may offer a potential therapeutic strategy for bone cancer pain.


Subject(s)
Bone Neoplasms/metabolism , Cancer Pain/metabolism , Receptor Protein-Tyrosine Kinases/metabolism , Receptors, Purinergic P2X3/metabolism , Wnt Proteins/metabolism , Animals , Benzylamines/pharmacology , Bone Neoplasms/pathology , Cancer Pain/pathology , Cell Line, Tumor , Male , Mice , Mice, Inbred C3H , Pain Measurement/drug effects , Pain Measurement/methods , Phenols/pharmacology , Polycyclic Compounds/pharmacology , Protein Kinase Inhibitors/pharmacology , Protein Transport/drug effects , Protein Transport/physiology , Purinergic P2X Receptor Antagonists/pharmacology , Sulfonamides/pharmacology
16.
Article in English | MEDLINE | ID: mdl-32419815

ABSTRACT

Eucommia ulmoides Oliv. is a traditional medical plant in Asia; however, it is still unknown whether Eucommia male flowers have an antihypertensive activity. In this study, we found that the aqueous extract of Eucommia ulmoides Oliv. male flowers can lower the blood pressure of SHR in a dose-dependent manner. Mechanistic studies suggested that the aqueous extract of male flowers can promote the mRNA and protein expressions of ACE2 in the kidney of SHR. ELISA assay showed that the plasma levels of ANG II was decreased, while ANG-(1-7) was increased in SHR treated with the aqueous extract of male flowers. ACE2 inhibitor DX600 can reverse the aqueous extract of Eucommia ulmoides Oliv. male flower-induced downregulation of Ang II and upregulation of Ang-(1-7), as well as the reduction of blood pressure in SHR. Moreover, Ang-(1-7)-Mas receptor antagonist A-779 abolished the antihypertensive effects of the aqueous extract of Eucommia ulmoides Oliv. male flower in SHR. The aqueous extract of Eucommia ulmoides Oliv. male flowers exhibited an antihypertensive action through the activation of ACE2-Ang-(1-7)-Mas signaling pathways in spontaneously hypertensive rats.

17.
Huan Jing Ke Xue ; 41(1): 368-376, 2020 Jan 08.
Article in Chinese | MEDLINE | ID: mdl-31854939

ABSTRACT

The Shen-Fu region is an important urban area in northeast China. We report on a study of the distribution of polybrominated diphenyl ethers (PBDEs) in representative topsoil from this region. In the summer of 2016, 72 soil samples from three cities (Shenyang, Fushun, and Shen-Fu New City) were collected, which covered four land use types:urban, rural residential, cultivated, and woodland. We report on the concentrations, compositions, and distributions of 14 PBDEs in soil and explore their sources, and additionally undertake human exposure analysis and health risk assessments. The results showed that the concentration of ∑14PBDEs in the topsoil ranged from 0.279-50.719 ng·g-1(dry weight), with a mean of (10.466±9.246) ng·g-1. The concentrations of PBDEs was ranked for the cities as:Fushun > Shenyang > Shen-Fu New City > background, and for different land use types as:urban land > rural residential land > cultivated land > forest. Deca-PBDE had the highest proportion of all congeners, accounting for 81.25%-89.23% of all PBDEs. Source analysis indicated that commercial Deca-PBDE was the main source, contributing 66.06% of the total Deca-PBDE according to principal component analysis/multiple linear regression (PCA-MLR). Among five different age groups assessed for exposure, children in Fushun had the highest exposure dose:(20.98±25.01) ng·(kg·d)-1. In terms of different land types, the highest exposure dose was for children living in urban areas:(18.54±20.27) ng·(kg·d)-1. The non-oncogenic health risks in the Shen-Fu region are of a relatively low level.


Subject(s)
Environmental Monitoring , Halogenated Diphenyl Ethers/analysis , Soil Pollutants/analysis , Child , China , Cities , Humans , Risk Assessment
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