179. CHARACTERISATION OF THE IN VITRO FUNCTION OF ACTIVIN AC

2009 ◽  
Vol 21 (9) ◽  
pp. 97
Author(s):  
E. Gold ◽  
C. Harrison ◽  
Y. Makanji ◽  
G. Risbridger
Keyword(s):  
Physiological Role ◽  
Activin A ◽  
Type I ◽  
Lncap Cells ◽  
Inhibitory Effects ◽  
Signalling Molecules ◽  
Growth Inhibitory ◽  
Potent Growth

Activins are members of the TGF-β superfamily that signal via type II and type I receptor subunits and intracellular Smads1. Activin A stimulates FSH release from the pituitary and is also a potent growth and differentiation factor in many physiological systems2. Over-expression of the activin-βC subunit in vitro leads to a reduction in activin A and an increase in activin AC3. Transgenic mice over-expressing activin-βC show decreased circulating activin A, implying that activin AC may also be formed in vivo4. Recently recombinant activin AC has become available, therefore this study examines the in vitro function and mechanism of action of activin AC. Activin AC stimulates FSH release in LβT2 cells and is a negative growth regulator in LNCaP cells, however the potency of activin AC is 8-10 fold less than activin A. Incubation of LNCaP cells with activin receptor antibodies (ALK4, ActRIIA, ActRIIB) abolishes the growth inhibitory effects of activin AC. Activin AC binds to ActRIIB, however a 20-30 fold decrease in both the potency and affinity of activin AC is evident compared to activin A. In addition, activin AC increases Smad-2 phosphorylation. These results indicate activin AC utilises the same receptors and intracellular signalling molecules as activin A. The activin A antagonists, follistatin and activin C4, also antagonise the growth inhibitory effects of activin AC and reduce Smad-2 phosphorylation and Smad-4 expression. This study shows for the first time that the in vitro function of activin AC is similar to activin A, albeit at a lower potency and provides the impetus to determine the physiological role of activin AC in vivo.

scholarly journals Trichostatin A downregulates bromodomain and extra-terminal proteins to suppress osimertinib resistant non-small cell lung carcinoma

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Yuting Meng ◽  
Xixi Qian ◽  
Li Zhao ◽  
Nan Li ◽  
Shengjie Wu ◽  
...  
Keyword(s):  
Trichostatin A ◽  
Small Cell Lung Carcinoma ◽  
Cell Types ◽  
Inhibitory Effects ◽  
Cell Lung Carcinoma ◽  
Growth Inhibitory ◽  
Terminal Proteins ◽  
P Cells

Abstract Background The third-generation epithelial growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) have shown significant therapeutic effects on patients with non-small cell lung carcinoma (NSCLC) who carry active EGFR mutations, as well as those who have developed acquired resistance to the first-generation of EGFR-TKIs due to the T790M mutation. However, most patients develop drug resistance after 8–10 months of treatment. Currently, the mechanism has not been well clarified, and new therapeutic strategies are urgently needed. Methods Osimertinib resistant cell lines were established by culturing sensitive cells in chronically increasing doses of osimertinib. The anticancer effect of reagents was examined both in vitro and in vivo using the sulforhodamine B assay and a xenograft mouse model. The molecular signals were detected by western blotting. The combination effect was analyzed using CompuSyn software. Results We found that bromodomain and extra-terminal proteins (BETs) were upregulated in osimertinib resistant (H1975-OR) cells compared with those in the paired parental cells (H1975-P), and that knockdown of BETs significantly inhibited the growth of H1975-OR cells. The BET inhibitor JQ1 also exhibited stronger growth-inhibitory effects on H1975-OR cells and a greater expression of BETs and the downstream effector c-Myc than were observed in H1975-P cells. The histone deacetylase (HDAC) inhibitor trichostatin A (TSA) showed stronger growth suppression in H1975-OR cells than in H1975-P cells, but vorinostat, another HDAC inhibitor, showed equal inhibitory efficacy in both cell types. Consistently, downregulation of BET and c-Myc expression was greater with TSA than with vorinostat. TSA restrained the growth of H1975-OR and H1975-P xenograft tumors. The combination of TSA and JQ1 showed synergistic growth-inhibitory effects in parallel with decreased BET and c-Myc expression in both H1975-OR and H1975-P cells and in xenograft nude mouse models. BETs were not upregulated in osimertinib resistant HCC827 cells compared with parental cells, while TSA and vorinostat exhibited equal inhibitory effects on both cell types. Conclusion Upregulation of BETs contributed to the osimertinib resistance of H1975 cells. TSA downregulated BET expression and enhanced the growth inhibitory effect of JQ1 both in vitro and in vivo. Our findings provided new strategies for the treatment of osimertinib resistance.

scholarly journals Innate triggering and antiviral effector functions of activin A

2021 ◽  
Author(s):  
Kinda Al-Hourani ◽  
Narayan Ramamurthy ◽  
Emanuele Marchi ◽  
Ruth M Eichinger ◽  
Lian N Lee ◽  
...  
Keyword(s):  
Viral Infection ◽  
Influenza A ◽  
Mononuclear Cells ◽  
Human Peripheral Blood ◽  
Activin A ◽  
Type I ◽  
Type I Ifn ◽  
Effector Functions

First-line defence against viral infection is contingent upon rapid detection of conserved viral structural and genomic motifs by germline-encoded pattern recognition receptors, followed by activation of the type I IFN system and establishment of an intracellular antiviral state. Novel antiviral functions of bone morphogenetic protein and related activin cytokines, acting in conjunction with, and independently of, type I IFN, have recently been described. Activin A mediates multiple innate and adaptive immune functions, including antiviral effects. However, how such effects are mediated and how activin might be triggered by viral infection have not been defined. Here we addressed this in vivo and in vitro, in humans and mice. Transcriptomic analyses delineated strikingly congruent patterns of gene regulation in hepatocytes stimulated with recombinant activin A and IFNα in vitro. Activin A mRNA, encoded by INHBA, is induced upon activation of RIG-I, MDA5 and TLR7/8 viral nucleic acid sensors in vitro, across multiple cell lines and in human peripheral blood mononuclear cells. In vivo, infection of mice with influenza A also upregulated Inhba mRNA in the lung; this local upregulation of Inhba is retained in MAVS knockout mice, indicating a role for non-RIG-I-like receptors in its induction. Activin induction and signalling were also detectable in patients with chronic viral hepatitis. Together, these data suggest Activin A is triggered in parallel with type I IFN responses and can trigger related antiviral effector functions. This model has implications for the development of targeted antiviral therapies, in addition to revealing novel facets of activin biology.

In vitro and in vivo growth-inhibitory effects of cladribine on neoplastic mast cells exhibiting the imatinib-resistant KIT mutation D816V

2010 ◽  
Vol 38 (9) ◽  
pp. 744-755 ◽  
Author(s):  
Alexandra Böhm ◽  
Karoline Sonneck ◽  
Karoline V. Gleixner ◽  
Karina Schuch ◽  
Winfried F. Pickl ◽  
...  
Keyword(s):  
Mast Cells ◽  
Inhibitory Effects ◽  
Kit Mutation ◽  
Growth Inhibitory ◽  
Imatinib Resistant ◽  
In Vivo Growth

scholarly journals Fusion of the N-terminal 119 amino acids with the RelA-CTD renders its growth inhibitory effects (p)ppGpp-dependent

2021 ◽  
Author(s):  
Jayashree Pohnerkar ◽  
Krishma Tailor ◽  
Prarthi Sagar ◽  
Keyur Dave
Keyword(s):  
Amino Acids ◽  
Feedback Regulation ◽  
Inhibitory Effects ◽  
E Coli ◽  
Growth Inhibitory ◽  
In The Wild ◽  
Regulatory Aspect ◽  
And Function

The guanosine nucleotide derivatives ppGpp and pppGpp are central to the remarkable capacity of bacteria to adapt to fluctuating environment and metabolic perturbations. These alarmones are synthesized by two proteins, RelA and SpoT in E. coli and the activities of each of the two enzymes are highly regulated for homeostatic control of (p)ppGpp levels in the cell. Although the domain structure and function of RelA are well defined, the findings of this study unfold the regulatory aspect of RelA that is possibly relevant in vivo. We uncover here the importance of the N-terminal 1-119 amino acids of the enzymatically compromised (p)ppGpp hydrolytic domain (HD) of monofunctional RelA for the (p)ppGpp mediated regulation of RelA-CTD function. We find that even moderate level expression of RelA appreciably reduces growth when the basal levels of (p)ppGpp in the cells are higher than in the wild type, an effect independent of its ability to synthesize (p)ppGpp. This is evidenced by the growth inhibitory effects of oversynthesis of the RelA-CTD in the relA+ strain but not in relA null mutant, suggesting the requirement of the functional RelA protein for basal level synthesis of (p)ppGpp, accordingly corroborated by the restoration of the growth inhibitory effects of the RelA-CTD expression in the relA1 spoT202 mutant. The N-terminal 119 amino acids of RelA fused in-frame with the RelA-CTD, both from 406-744 amino acids (including TGS) and from 454-744 amino acids (sans TGS) caused growth inhibition only in spoT1 and spoT202 relA1 mutants, uncovering the hitherto unrealized (p)ppGpp-dependent regulation of RelA-CTD function. An incremental rise in the (p)ppGpp levels is proposed to progressively modulate the interaction of RelA-CTD with the ribosomes, with possible implications in the feedback regulation of the N-terminal (p)ppGpp synthesis function, a proposal that best explains the nonlinear relationship between (p)ppGpp synthesis and increased ratio of RelA:ribosomes, both in vitro as well as in vivo.

The Anticancer Effect of Sanguinarine: A Review

2018 ◽  
Vol 24 (24) ◽  
pp. 2760-2764 ◽  
Author(s):  
Chenxing Fu ◽  
Guiping Guan ◽  
Hongbing Wang
Keyword(s):  
Tumor Cell ◽  
In Vivo Studies ◽  
Inhibitory Effects ◽  
Anticancer Effect ◽  
Growth Inhibitory ◽  
Cell Proliferation Inhibition ◽  
Anti Cancer ◽  
Induced Apoptosis

In vitro and in vivo studies have revealed that Sanguinarine has antioxidant, anti-inflammatory, proapoptotic, and growth inhibitory effects on tumor cells of a variety of cancers. Previous research showed that sanguinarine induced apoptosis (cell death) and/or antiproliferative while reducing tumor cell antiangiogenic and anti-invasive properties. This paper describes various sanguinarine anti-cancer mechanisms, including inhibition of erroneously-activated signal transduction pathways, apoptosis, and tumor cell proliferation inhibition.

Growth inhibitory effects of pegylated IFN ?-2b on human liver cancer cells in vitro and in vivo

2006 ◽  
Vol 26 (8) ◽  
pp. 964-975 ◽  
Author(s):  
Hirohisa Yano ◽  
Sachiko Ogasawara ◽  
Seiya Momosaki ◽  
Jun Akiba ◽  
Sakiko Kojiro ◽  
...  
Keyword(s):  
Liver Cancer ◽  
Cancer Cells ◽  
Human Liver ◽  
Inhibitory Effects ◽  
Liver Cancer Cells ◽  
Growth Inhibitory ◽  
Human Liver Cancer ◽  
Human Liver Cancer Cells

Growth-inhibitory effects of the synthetic retinoid CD437 against ovarian carcinoma models in vitro and in vivo

1998 ◽  
Vol 42 (5) ◽  
pp. 429-432 ◽  
Author(s):  
Simon P. Langdon ◽  
Genevieve J. Rabiasz ◽  
Alison A. Ritchie ◽  
Uwe Reichert ◽  
Peter Buchan ◽  
...  
Keyword(s):  
Ovarian Carcinoma ◽  
Inhibitory Effects ◽  
Synthetic Retinoid ◽  
Growth Inhibitory

193 BISPHENOL A AND PHTHALATE ENHANCED THE GROWTH OF PROSTATE CANCER CELLS AND ALTERED TGF-β SIGNALING MOLECULES VIA AN ESTROGEN RECEPTOR OR ANDROGEN RECEPTOR-DEPENDENT PATHWAY IN IN VITRO AND IN VIVO MODELS

2013 ◽  
Vol 25 (1) ◽  
pp. 245 ◽  
Author(s):  
H.-R. Lee ◽  
S.-H. Hyun ◽  
E.-B. Jeung ◽  
K.-C. Choi
Keyword(s):  
Prostate Cancer ◽  
Cancer Cells ◽  
Endocrine System ◽  
Signalling Pathways ◽  
Lncap Cells ◽  
Prostate Cancer Cells ◽  
Gene Expressions ◽  
Signalling Molecules

Endocrine-disrupting chemicals (EDC) can bind to the hormone receptor and induce an unexpected hormone response to activate oestrogen receptor (ER)- and androgen receptor (AR)-mediated signalling pathways. Among EDC, bisphenol A (BPA) has a detrimental effect on the endocrine system and is suspected to promote human breast and ovarian cancers. Recent studies have reported that phthalate can disrupt the endocrine system and has a weak estrogenic activity with binding to ER. In this study, we demonstrated whether BPA and dibutyl phthalate (DBP) stimulate the proliferation of prostate cancer cells, LNCaP cells, which have both ER and AR. We evaluated the proliferative rate of LNCaP cells following BPA and DBP treatment using a cell viability assay compared with EtOH treatment as a negative control. Further, we examined the alteration of cell cycle-related gene expressions and TGF-β signalling molecules by semiquantitative RT-PCR. Both BPA and DBP increased LNCaP cell growth more than 2-fold. Moreover, these EDC altered transcriptional expressions of cell cycle-related genes, cyclin D1 and p21, at 6 h in LNCaP cells after exposure of BPA and DBP. Like 17β-oestradiol (E2) and dihydrotestosterone (DHP), treatments of BPA and DBP lead to an increase of the transcriptional levels of c-myc and c-fos in LNCaP cells from 30 min to 6 h. In addition, BPA and DBP decreased the protein level of not only p-smad but also total smad, suggesting that these EDC can affect the molecules of the TGF-β signalling pathway. It was of interest that these effects of EDC were reversed by an antagonist of ER or AR signalling pathways in these prostate cancer cells. These results suggest that BPA and phthalate can alter various gene expressions in TGF-β signalling molecules and stimulate cell growth in prostate cancer cells in vitro. In addition, the growth of prostate cancer cells was stimulated following the exposure of E2, DHT, and DBP in vivo. Taken together, these results indicate the potential of BPA and phthalate in the carcinogenesis of prostate cancer by the oestrogen or androgen-dependent signalling pathway. This work was supported by a National Research Foundation of Korea (NRF) grant funded by the Ministry of Education, Science and Technology (MEST) of Korea government (no. 2011-0015385).

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