Regulation of rat alveolar type 2 cell proliferation in vitro involves type II cAMP-dependent protein kinase

2007 ◽  
Vol 292 (1) ◽  
pp. L232-L239 ◽  
Author(s):  
Jan T. Samuelsen ◽  
Per E. Schwarze ◽  
Henrik S. Huitfeldt ◽  
E. Vibeke Thrane ◽  
Marit Låg ◽  
...  
Keyword(s):  
Cell Proliferation ◽  
Alveolar Type ◽  
Regulatory Subunits ◽  
Anchoring Protein ◽  
Dependent Protein ◽  
Cycle Dependent ◽  
Proliferation In Vitro

To elucidate the role of cAMP and different cAMP-dependent protein kinases (PKA; A-kinase) in lung cell proliferation, we investigated rat alveolar type 2 cell proliferation in relation to activation or inhibition of PKA and PKA regulatory subunits (RIIα and RIα). Both the number of proliferating type 2 cells and the level of different regulatory subunits varied during 7 days of culture. The cells exhibited a distinct peak of proliferation after 5 days of culture. This proliferation peak was preceded by a rise in RIIα protein level. In contrast, an inverse relationship between RIα and type 2 cell proliferation was noted. Activation of PKA increased type 2 cell proliferation if given at peak RIIα expression. Furthermore, PKA inhibitors lowered the rate of proliferation only when a high RII level was observed. An antibody against the anchoring region of RIIα showed cell cycle-dependent binding in contrast to antibodies against other regions, possibly related to altered binding to A-kinase anchoring protein. Following activation of PKA, relocalization of RIIα was confirmed by immunocytochemistry. In conclusion, it appears that activation of PKA II is important in regulation of alveolar type 2 cell proliferation.

ROLE OF PAF AND OXIDANT AGENTS ON VASCULAR CELL PROLIFERATION. IN VITRO IMPLICATION OF MTOR-DEPENDENT PATHWAY.

2004 ◽  
Vol 78 ◽  
pp. 741-742
Author(s):  
I Rama ◽  
M Riera ◽  
J Torras ◽  
J M Cruzado ◽  
I Herrero-Fresneda ◽  
...  
Keyword(s):  
Cell Proliferation ◽  
Vascular Cell ◽  
Proliferation In Vitro ◽  
Dependent Pathway

scholarly journals HNRNPA2B1 promotes multiple myeloma progression by increasing AKT3 expression via m6A-dependent stabilization of ILF3 mRNA

2021 ◽  
Vol 14 (1) ◽  
Author(s):  
Fengjie Jiang ◽  
Xiaozhu Tang ◽  
Chao Tang ◽  
Zhen Hua ◽  
Mengying Ke ◽  
...  
Keyword(s):  
Multiple Myeloma ◽  
Cell Proliferation ◽  
Cellular Proliferation ◽  
Aberrant Expression ◽  
The Stability ◽  
Induced Apoptosis ◽  
Proliferation In Vitro

AbstractN6-methyladenosine (m6A) modification is the most prevalent modification in eukaryotic RNAs while accumulating studies suggest that m6A aberrant expression plays an important role in cancer. HNRNPA2B1 is a m6A reader which binds to nascent RNA and thus affects a perplexing array of RNA metabolism exquisitely. Despite unveiled facets that HNRNPA2B1 is deregulated in several tumors and facilitates tumor growth, a clear role of HNRNPA2B1 in multiple myeloma (MM) remains elusive. Herein, we analyzed the function and the regulatory mechanism of HNRNPA2B1 in MM. We found that HNRNPA2B1 was elevated in MM patients and negatively correlated with favorable prognosis. The depletion of HNRNPA2B1 in MM cells inhibited cell proliferation and induced apoptosis. On the contrary, the overexpression of HNRNPA2B1 promoted cell proliferation in vitro and in vivo. Mechanistic studies revealed that HNRNPA2B1 recognized the m6A sites of ILF3 and enhanced the stability of ILF3 mRNA transcripts, while AKT3 downregulation by siRNA abrogated the cellular proliferation induced by HNRNPA2B1 overexpression. Additionally, the expression of HNRNPA2B1, ILF3 and AKT3 was positively associated with each other in MM tissues tested by immunohistochemistry. In summary, our study highlights that HNRNPA2B1 potentially acts as a therapeutic target of MM through regulating AKT3 expression mediated by ILF3-dependent pattern.

scholarly journals MiR-155-5p suppresses SOX1 to promote proliferation of cholangiocarcinoma via RAF/MEK/ERK pathway

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Da Wang ◽  
Fei Xiong ◽  
Guanhua Wu ◽  
Wenzheng Liu ◽  
Bing Wang ◽  
...  
Keyword(s):  
Cell Proliferation ◽  
Close Relation ◽  
Luciferase Reporter ◽  
Expression Levels ◽  
Erk Phosphorylation ◽  
Overexpressing Cell ◽  
Proliferation In Vitro

Abstract Background Accumulating evidence has demonstrated the close relation of SOX1 with tumorigenesis and tumor progression. Upregulation of SOX1 was recently shown to suppress growth of human cancers. However, the expression and role of SOX1 in cholangiocarcinoma (CCA) is not well characterized. Methods Expression levels of SOX1 in CCA tissues and normal bile duct tissues were examined using public GEO database. Western blot and immunohistochemistry were used to confirm the expression levels. Cell proliferation assay (CCK-8) and colony formation assay were performed to assess proliferation of CCA cells. A mouse model of subcutaneous transplantable tumors was used to evaluated proliferation of CCA in vivo. The putative regulating factor of SOX1 were determined using Targetscan and dual-luciferase reporter assay. Results SOX1 was downregulated in CCA tissues. Overexpression of SOX1 significantly inhibited cell proliferation in vitro and suppressed tumor growth in vivo. miR-155-5p directly targeted the 3′-untranslated region (3′UTR) of SOX1 and inhibited expression of SOX1, resulting in the activation of RAF, MEK and ERK phosphorylation, and thus CCA proliferation. However, restoration of SOX1 expression in miR-155-5p overexpressing cell lines decreased the phosphorylation level of RAF, MEK and ERK, as well as the proliferation of CCA cells. Conclusion MiR-155-5p decreased the expression of SOX1 by binding to its 3′UTR, which activated the RAF/MEK/ERK signaling pathway and promoted CCA progression.

scholarly journals Mesenchymal stromal cells attenuate alveolar type 2 cells senescence through regulating NAMPT-mediated NAD metabolism

2022 ◽  
Vol 13 (1) ◽  
Author(s):  
Xiaofan Lai ◽  
Shaojie Huang ◽  
Sijia Lin ◽  
Lvya Pu ◽  
Yaqing Wang ◽  
...  
Keyword(s):  
Pulmonary Fibrosis ◽  
Therapeutic Potential ◽  
Alveolar Type ◽  
Therapeutic Effects ◽  
Protective Effects ◽  
Nad Metabolism

Abstract Background Idiopathic pulmonary fibrosis (IPF) is a chronic and progressive deadly fibrotic lung disease with high prevalence and mortality worldwide. The therapeutic potential of mesenchymal stem cells (MSCs) in pulmonary fibrosis may be attributed to the strong paracrine, anti-inflammatory, anti-apoptosis and immunoregulatory effects. However, the mechanisms underlying the therapeutic effects of MSCs in IPF, especially in terms of alveolar type 2 (AT2) cells senescence, are not well understood. The purpose of this study was to evaluate the role of MSCs in NAD metabolism and senescence of AT2 cells in vitro and in vivo. Methods MSCs were isolated from human bone marrow. The protective effects of MSCs injection in pulmonary fibrosis were assessed via bleomycin mouse models. The senescence of AT2 cells co-cultured with MSCs was evaluated by SA-β-galactosidase assay, immunofluorescence staining and Western blotting. NAD+ level and NAMPT expression in AT2 cells affected by MSCs were determined in vitro and in vivo. FK866 and NAMPT shRNA vectors were used to determine the role of NAMPT in MSCs inhibiting AT2 cells senescence. Results We proved that MSCs attenuate bleomycin-induced pulmonary fibrosis in mice. Senescence of AT2 cells was alleviated in MSCs-treated pulmonary fibrosis mice and when co-cultured with MSCs in vitro. Mechanistic studies showed that NAD+ and NAMPT levels were rescued in AT2 cells co-cultured with MSCs and MSCs could suppress AT2 cells senescence mainly via suppressing lysosome-mediated NAMPT degradation. Conclusions MSCs attenuate AT2 cells senescence by upregulating NAMPT expression and NAD+ levels, thus exerting protective effects in pulmonary fibrosis.

scholarly journals MiR-155-5p Suppress SOX1 to Promote the Proliferation of Cholangiocarcinoma via RAF/MEK/ERK Pathway

2021 ◽  
Author(s):  
Da Wang ◽  
Fei Xiong ◽  
Guanhua Wu ◽  
Wenzheng Liu ◽  
Bing Wang ◽  
...  
Keyword(s):  
Cell Proliferation ◽  
Luciferase Reporter ◽  
Phosphorylation Level ◽  
Erk Phosphorylation ◽  
Overexpressing Cell ◽  
Proliferation In Vitro ◽  
Geo Database

Abstract BackgroundAccumulating evidences indicate that SOX1 is closely related to tumorigenesis and development, upregulation of SOX1 is recently reported to suppress growth of human cancers. However, the expression and role of SOX1 in cholangiocarcinoma (CCA) remain unknown.MethodsThe expression levels of SOX1 in CCA tissues and normal bile duct tissues were examined by public GEO database, and western blot and immunohistochemistry were used to confirm the expression again. Cell proliferation assay (CCK-8) and colony formation assay were performed to determine proliferation of CCA cells. A model of transplatable subcutaneously tumors in mouse was used to evaluated proliferation of CCA in vivo. The putative regulating factor of SOX1 were disclosed by Targetscan and a dual-luciferase reporter assay.ResultsSOX1 was downregulated in CCA tissues. Overexpression of SOX1 significantly inhibited cell proliferation in vitro and tumor growth in vivo. Furthermore, miR-155-5p directly targets 3’UTR of SOX1 and inhibits expression of SOX1, resulting in the activation of RAF, MEK and ERK phosphorylation and thus CCA proliferation. However, when SOX1 expression was restored in miR-155-5p overexpressing cell lines, the phosphorylation level of RAF, MEK and ERK were decreased, as well as the proliferation of CCA cells.ConclusionMiR-155-5p could bind to the 3’UTR of SOX1 to decrease the expression of SOX1, and further activated the RAF/MEK/ERK signaling pathway to promote CCA progression.

Activation of HGF/c-Met signaling by ultrafine carbon particles and its contribution to alveolar type II cell proliferation

2012 ◽  
Vol 302 (8) ◽  
pp. L755-L763 ◽  
Author(s):  
Chih-Ching Chang ◽  
Jia-Jhen Chiu ◽  
Shan-Ling Chen ◽  
Hui-Chun Huang ◽  
Hui-Fen Chiu ◽  
...  
Keyword(s):  
Cell Proliferation ◽  
Kinase Inhibitor ◽  
Carbon Particle ◽  
Alveolar Type ◽  
Type Ii ◽  
Type Ii Cell ◽  
Met Phosphorylation

Hepatocyte growth factor (HGF) is a potent mitogen and motogen for various epithelial cells. The present study aimed to explore the role of HGF and c-Met receptor in ultrafine carbon particle-induced alveolar type II epithelial (type II) cell proliferation. ICR mice were intratracheally instilled with 100 μg ultrafine carbon black (ufCB) and killed at 21, 48, and 72 days postexposure to examine type II cell proliferation, HGF release, and c-Met activation. In vivo and in vitro applications of neutralizing anti-HGF antibody were used to investigate the causal role of HGF in cell proliferation. The Met kinase inhibitor SU11274 and extracellular signal-regulated kinase 1/2 (ERK1/2) inhibitor PD98059 were used to delineate the involvement of c-Met/ERK1/2 in rat L2 pulmonary epithelial cell proliferation. The results demonstrated that in vivo exposure to 100 μg ufCB caused increased HGF in bronchoalveolar lavage fluid, as well as increased HGF production, c-Met phosphorylation, and cell proliferation in type II cells. In vitro study revealed that ufCB caused a dose-dependent increase in HGF release, c-Met phosphorylation, and cell proliferation. Importantly, treatment with the neutralizing anti-HGF antibody significantly blocked ufCB-induced in vivo and in vitro type II cell proliferation. Moreover, SU11274 and PD98059 significantly reduced ufCB-increased L2 cell proliferation. Results from Western blotting demonstrated that SU11274 successfully suppressed ufCB-induced phosphorylation of c-Met and ERK1/2. In summary, the activation of HGF/c-Met signaling is a major pathway involved in ufCB-induced type II cell proliferation.

scholarly journals Cullin-1 Regulates MG63 Cell Proliferation and Metastasis and is a Novel Prognostic Marker of Osteosarcoma

2017 ◽  
Vol 32 (2) ◽  
pp. 202-209 ◽  
Author(s):  
Qinghua Cheng ◽  
Guoyong Yin
Keyword(s):  
Cell Proliferation ◽  
Mg63 Cell ◽  
Osteosarcoma Cell ◽  
Mmp9 Expression ◽  
Proliferation And Metastasis ◽  
Reliable Marker ◽  
Proliferation In Vitro

Background There is no reliable marker available for early detection, diagnostic confirmation or disease prognosis of osteosarcoma. Cullin-1 (CUL1) is a newly reported tumor-related gene, and we aimed to unravel its role in osteosarcoma. Methods We used immunohistochemistry to analyze the correlation between CUL1 expression and clinicopathological variables and patient survival. To evaluate the function of CUL1, a group of 28 osteosarcoma patients were recruited for this study. The role of regulation of CUL1 in osteosarcoma was studied in vitro and in vivo. In addition, we further investigated the signaling pathway of CUL1 in osteosarcoma progression. Results We first discovered that CUL1 expression was up-regulated in human osteosarcoma tissues and inversely correlated with osteosarcoma differentiation. In addition, CUL1 promotes osteosarcoma cell proliferation in vitro and in vivo. We also found that CUL1 promotes osteosarcoma cell invasion and metastasis in vitro and in vivo. High levels of CUL1 promote osteosarcoma progression via up-regulation of MMP9 expression. Conclusions Our results demonstrate that increased CUL1 expression is significantly correlated with poor prognosis of patients with osteosarcoma. CUL1 might be an important marker and a therapeutic target for osteosarcoma.

Cell proliferation is not required for the initiation of early cleft formation in mouse embryonic submandibular epithelium in vitro

Development ◽  
1987 ◽  
Vol 99 (3) ◽  
pp. 429-437 ◽  
Author(s):  
Y. Nakanishi ◽  
T. Morita ◽  
H. Nogawa
Keyword(s):  
Cell Proliferation ◽  
Dna Synthesis ◽  
Specific Inhibitor ◽  
X Rays ◽  
X Ray ◽  
Mitotic Figures ◽  
Cleft Formation ◽  
Proliferation In Vitro

An X-ray irradiation method was employed to analyse the role of cell proliferation in vitro in the cleft formation of mouse embryonic submandibular epithelium at early stages. When the mid 12-day gland was exposed to 200 rad of X-rays, the growth was severely retarded. In contrast, late 12-day and early 13-day glands grew apparently in a normal fashion, as did the control gland, for up to 40 h. In either case, they formed shallow clefts within 10 h of culture. With 1000 rad irradiation, the mid 12-day gland did not grow at all, but formed clefts within 20 h of culture followed by a rapid degeneration. Under the same conditions, the growth of the late 12-day gland, which was at the stage just before branching, was retarded until 10 h of culture, followed by a slight increase in epithelial size, but cleft formation was also observed within 6–10 h, as in the control gland. When exposed to a dose of 1000 rad of X-rays, the early 13-day and the late 12-day glands exhibited similar radiosensitivity; the initial narrow clefts in the epithelium deepened and new clefts began to form within 6–10 h of culture. [3H]thymidine incorporation studies revealed that a dose of 1000 rad reduced DNA synthesis of mid and late 12-day glands by 72 and 65%, respectively. Histological examination of X-irradiated late 12-day gland showed that mitotic figures were rarely seen in the epithelium at 6 h of culture. Aphidicolin, a specific inhibitor of DNA synthesis, could not halt the cleft formation of the late 12-day gland. In this experiment 89% of DNA synthesis was inhibited. Treatment of an X-ray irradiated late 12-day gland with aphidicolin blocked 92% of the DNA synthesis, but did not prevent cleft formation taking place. These results indicate that neither cell division nor DNA synthesis, is required for the initiation process of the cleft formation of the mouse embryonic submandibular epithelium at early morphogenetic stages in vitro.

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