The CDK inhibitor NtKIS1a is involved in plant development,endoreduplication and restores normal development of cyclin D3;1-overexpressing plants

2002 ◽  
Vol 115 (5) ◽  
pp. 973-982 ◽  
Author(s):  
Sophie Jasinski ◽  
Catherine Riou-Khamlichi ◽  
Odile Roche ◽  
Claudette Perennes ◽  
Catherine Bergounioux ◽  
...  

Plant development requires stringent controls between cell proliferation and cell differentiation. Proliferation is positively regulated by cyclin dependent kinases (CDKs). Acting in opposition to CDKs are CDK inhibitors(CKIs). The first tobacco CKI (NtKIS1a) identified was shown to inhibit in vitro the kinase activity of CDK/cyclin complexes and to interact with CDK and D-cyclins. However, these features, which are common to other plant and animal CKIs already characterised, did not provide information about the function of NtKIS1a in plants. Thus, to gain insight into the role of NtKIS1a and especially its involvement in cell proliferation during plant development, we generated transgenic Arabidopsis thaliana plants that overexpress NtKIS1a. These plants showed reduced growth with smaller organs that contained larger cells. Moreover, these plants displayed modifications in plant morphology. These results demonstrated that plant organ size and shape,as well as organ cell number and cell size, might be controlled by modulation of the single NtKIS1a gene activity. Since in mammals, D-cyclins control cell cycle progression in a CDK-dependent manner but also play a CDK independent role by sequestering the CKIs p27Kip1 and p21Cip1, we tested the significance of cyclin D-CKI interaction within a living plant. With this aim, NtKIS1a and AtCycD3;1 were overexpressed simultaneously in plants by two different methods. Our results demonstrated that overexpression of the CKI NtKIS1a restores essentially normal development in plants overexpressing AtCycD3;1, providing the first evidence of cyclin D-CKI co-operation within the context of a living plant.

Nutrients ◽  
2021 ◽  
Vol 13 (7) ◽  
pp. 2178
Author(s):  
Fabio Morandi ◽  
Veronica Bensa ◽  
Enzo Calarco ◽  
Fabio Pastorino ◽  
Patrizia Perri ◽  
...  

Neuroblastoma (NB) is the most common extra-cranial solid tumor of pediatric age. The prognosis for high-risk NB patients remains poor, and new treatment strategies are desirable. The olive leaf extract (OLE) is constituted by phenolic compounds, whose health beneficial effects were reported. Here, the anti-tumor effects of OLE were investigated in vitro on a panel of NB cell lines in terms of (i) reduction of cell viability; (ii) inhibition of cell proliferation through cell cycle arrest; (iii) induction of apoptosis; and (iv) inhibition of cell migration. Furthermore, cytotoxicity experiments, by combining OLE with the chemotherapeutic topotecan, were also performed. OLE reduced the cell viability of NB cells in a time- and dose-dependent manner in 2D and 3D models. NB cells exposed to OLE underwent inhibition of cell proliferation, which was characterized by an arrest of the cell cycle progression in G0/G1 phase and by the accumulation of cells in the sub-G0 phase, which is peculiar of apoptotic death. This was confirmed by a dose-dependent increase of Annexin V+ cells (peculiar of apoptosis) and upregulation of caspases 3 and 7 protein levels. Moreover, OLE inhibited the migration of NB cells. Finally, the anti-tumor efficacy of the chemotherapeutic topotecan, in terms of cell viability reduction, was greatly enhanced by its combination with OLE. In conclusion, OLE has anti-tumor activity against NB by inhibiting cell proliferation and migration and by inducing apoptosis.


2017 ◽  
Vol 138 (2) ◽  
pp. 103-110 ◽  
Author(s):  
Yang Liu ◽  
Xiaochen Yu ◽  
Junling Zhuang

Objectives: To explore the effect of the β-adrenoreceptor signaling pathway on myeloma cells. Methods: The myeloma U266 cell line was treated with epinephrine and propranolol. Cell proliferation was analyzed by MTS assay. Apoptosis was detected by flow cytometry. The β-receptor subtype and the key enzyme of epinephrine were identified by reverse transcription polymerase chain reaction (RT-PCR). Results: Epinephrine (5-50 μM) promoted U266 cell growth in a dose-dependent manner and neutralized the inhibition effect of bortezomib (25 and 50 ng/mL) in vitro. Cell proliferation was inhibited by a β-receptor antagonist, propranolol, at a concentration of 50-200 μM. The proportions of early and late apoptotic cells were enhanced after treatment with propranolol. The expression of caspase 3/7, 8, and 9 was elevated in propranolol-treated myeloma cells. Both β1- and β2-adrenoceptor mRNAs were expressed in the U266 cell line. Key enzymes dopamine hydroxylase and tyrosinehydroxylase were identified in myeloma cells. Conclusions: Our results reveal that epinephrine stimulates myeloma cell growth in vitro while the β-blocker propranolol has an antiproliferative effect, indicating that stress hormones may trigger the progression of myeloma.


2021 ◽  
Author(s):  
Xuyang Lv ◽  
Jiangchuan Sun ◽  
Linfeng Hu ◽  
Ying Qian ◽  
Chunlei Fan ◽  
...  

Abstract Background: Although curcumol has been shown to possess antitumor effects in several cancers, its effects on glioma are largely unknown. Recently, lncRNAs have been reported to play an oncogenic role through epigenetic modifications. Therefore, here, we investigated whether curcumol inhibited glioma progression by reducing FOXD2-AS1-mediated enhancer of zeste homolog 2 (EZH2) activation.Methods: MTT, colony formation, flow cytometry, Transwell, and neurosphere formation assays were used to assess cell proliferation, cell cycle, apoptosis, the percentage of CD133+ cells, the migration and invasion abilities, and the self-renewal ability. qRT-PCR, western blotting, immunofluorescence, and immunohistochemical staining were used to detect mRNA and protein levels. Isobologram analysis and methylation-specific PCR were used to analyze the effects of curcumol on TMZ resistance in glioma cells. DNA pull-down and Chip assays were employed to explore the molecular mechanism underlying the functions of curcumol in glioma cells. Tumorigenicity was determined using a xenograft formation assay. Results: Curcumol inhibited the proliferation, metastasis, self-renewal ability, and TMZ resistance of glioma cells in vitro and in vivo. FOXD2-AS1 was highly expressed in glioma cell lines, and its expression was suppressed by curcumol treatment in a dose- and time-dependent manner. The forced expression of FOXD2-AS1 abrogated the effect of curcumol on glioma cell proliferation, metastasis, self-renewal ability, and TMZ resistance. Moreover, the forced expression of FOXD2-AS1 reversed the inhibitory effect of curcumol on EZH2 activation.Conclusions: We showed for the first time that curcumol is effective in inhibiting malignant biological behaviors and TMZ-resistance of glioma cells by suppressing FOXD2-AS1-mediated EZH2 activation on anti-oncogenes. Our findings offer the possibility of exploiting curcumol as a promising therapeutic agent for glioma treatment and may provide an option for the clinical application of this natural herbal medicine.


1998 ◽  
Vol 275 (1) ◽  
pp. L71-L79 ◽  
Author(s):  
Elodie Nabeyrat ◽  
Valérie Besnard ◽  
Sophie Corroyer ◽  
Véronique Cazals ◽  
Annick Clement

Retinoids, including retinol and retinoic acid (RA) derivatives, are important molecules for lung growth and homeostasis. The presence of RA receptors and of RA-binding proteins in the alveolar epithelium led to suggest a role for RA on alveolar epithelial cell replication. In the present study, we examined the effects of RA on proliferation of the stem cells of the alveolar epithelium, the type 2 cells. We showed that treatment of serum-deprived type 2 cells with RA led to a stimulation of cell proliferation, with an increase in cell number in a dose-dependent manner. To gain some insights into the mechanisms involved, we studied the effects of RA on the expression of several components of the insulin-like growth factor (IGF) system that have been shown to be associated with the growth arrest of type 2 cells, mainly the IGF-binding protein-2 (IGFBP-2), IGF-II, and the type 2 IGF receptor. We documented a marked decrease in the expression of these components upon RA treatment. Using conditioned media from RA-treated cells, we provided evidence that the proliferative response of type 2 cells to RA was mediated through production of growth factor(s) distinct from IGF-I. We also showed that RA was able to reduce the decrease in cell number observed when type 2 cells were treated with transforming growth factor (TGF)-β1. These results together with the known stimulatory effect of TGF-β1 on IGFBP-2 expression led to suggest that RA may be associated with type 2 cell proliferation through mechanisms interfering with the TGF-β1 pathway.


2020 ◽  
Vol 13 (9) ◽  
pp. 208
Author(s):  
Min-Hee Kim ◽  
Tae Hyeong Lee ◽  
Jin Soo Lee ◽  
Dong-Jun Lim ◽  
Peter Chang-Whan Lee

Hypoxia-inducible factor (HIF)-1α plays an important role in cancer progression. In various cancers, including thyroid cancer, overexpression of HIF-1α is related to poor prognosis or treatment response. However, few studies have investigated the role of HIF-1α inhibition in thyroid cancer progression. We evaluated the utility of the HIF-1α inhibitor IDF-11774 in vitro utilizing two thyroid cancer cell lines, K1 and BCPAP. Both cell lines were tested to elucidate the effects of IDF-11774 on cell proliferation and migration using soft agar and invasion assays. Here, we found that a reduction of HIF-1α expression in BCPAP cells was observed after treatment with IDF-11774 in a dose-dependent manner. Moreover, cell proliferation, migration, and anchorage-independent growth were effectively inhibited by IDF-11774 in BCPAP cells but not in K1 cells. Additionally, invasion of BCPAP but not K1 cells was controlled with IDF-11774 in a dose-dependent manner. Our findings suggest that promoting the degradation of HIF-1α could be a strategy to manage progression and that HIF-1α inhibitors are potent drugs for thyroid cancer treatment.


2009 ◽  
Vol 204 (2) ◽  
pp. 135-142 ◽  
Author(s):  
Salvatore Ulisse ◽  
Yannick Arlot-Bonnemains ◽  
Enke Baldini ◽  
Stefania Morrone ◽  
Silvia Carocci ◽  
...  

The aurora kinase family members, Aurora-A, -B, and -C (listed as AURKA, AURKB and AURKC respectively in the HUGO Database), are serine/threonine kinases involved in the regulation of chromosome segregation and cytokinesis, and alterations in their expression are associated with malignant cell transformation and genomic instability. Deregulation of the expression of the aurora kinases has been shown to occur also in testicular germ cell tumors (TGCTs) identifying them as putative anticancer therapeutic targets. We here evaluated the in vitro effects of MK-0457, an aurora kinases inhibitor, on cell proliferation, cell cycle, ploidy, apoptosis, and tumorigenicity on the TGCT-derived cell line NT2-D1. Treatment with MK-0457 inhibited cell proliferation in a time- and dose-dependent manner, with IC50=17.2±3.3 nM. MK-0457 did not affect the expression of the three aurora kinases, but prevented their ability to phosphorylate substrates relevant to the mitotic progression. Time-lapse experiments demonstrated that MK-0457-treated cells entered mitosis but were unable to complete it, presenting after short time the typical features of apoptotic cells. Cytofluorimetric analysis confirmed that the treatment with MK-0457 for 6 h induced NT2-D1 cells accumulation in the G2/M phase of the cell cycle and the subsequent appearance of sub-G0 nuclei. The latter result was further supported by the detection of caspase-3 activation following 24-h treatment with the inhibitor. Finally, MK-0457 prevented the capability of the NT2-D1 cells to form colonies in soft agar. In conclusion, the above findings demonstrate that inhibition of aurora kinase activity is effective in reducing in vitro growth and tumorigenicity of NT2-D1 cells, and indicate its potential therapeutic value for TGCT treatment.


2008 ◽  
Vol 21 (04) ◽  
pp. 337-342 ◽  
Author(s):  
M. A. Hossain ◽  
J. Park ◽  
S. H. Choi ◽  
G. Kim

SummaryDexamethasone (Dexa) has been commonly used in humans and domestic animals, particularly in the treatment of tendon injuries and cartilage degeneration. However, it is often associated with tendon rupture and impaired tendon and cartilage healing. In the present study, we investigated Dexa’s in vitro effects on the growth of cell proliferation and the induction of apoptosis in canine Achilles tendon cells and chondrocytes. Cell proliferation after treatment with Dexa for two to six days was quantified by a 2,3-bis{2-methoxy- 4-nitro-5-sulfophenyl}-2H-tetrazolium-5-carboxyanilide inner salt assay (XTT). The results showed that Dexa could inhibit the proliferation of tendon cells and chondrocytes at increasing concentrations (0.1–50 μg/ml) compared with untreated cells. Cell apoptosis was induced by Dexa, as evidenced by the typical nuclear apoptosis using Hoechst 33258 staining. Dexa increased the apoptosis of canine tendon cells and chondrocytes in a time-dependent manner. In canine tendon cells and chondrocytes that were treated with 25 and 50 μg/ml concentration of Dexa, the number of condensed apoptotic nuclei was significantly increased. In addition, culturing with Dexa and the glucocorticoid receptor blocker, mifepristone, significantly arrested apoptosis of tendon cells and chondrocytes. Based on our in vitro data, we hypothesized that in vivo treatment with glucocorticoids may diminish the proliferation of tendon and cartilage cells by increasing apoptosis and suppressing the proliferation. Our findings suggest that Dexa could be used with caution in dogs with articular or tendon problems.


2020 ◽  
Vol 15 (1) ◽  
pp. 1934578X2090255
Author(s):  
Eunbi Jo ◽  
Hyun-Jin Jang ◽  
Kyeong E. Yang ◽  
Min S. Jang ◽  
Yang H. Huh ◽  
...  

This study aimed to investigate the effect of Cordyceps militaris extract on the proliferation and apoptosis of carboplatin- resistant SKOV-3 and determine the underlying mechanisms for overcoming carboplatin resistance in human ovarian cancer. We cultured the carboplatin-resistant SKOV-3 cells in vitro until the exponential growth phase and then treated with different concentrations of C. militaris for 24, 48, and 72 hours. We performed cell proliferation assay, cell morphological change assessment using transmission electron microscopy, apoptosis assay, and immunoblotting to measure the protein expression of caspase-3 and -8, poly (ADP-ribose) polymerase (PARP)-1, B-cell lymphoma (Bcl)-2, and activating transcription factor 3 (ATF3)/TP53 signaling-related proteins. As a result, C. militaris reduced the viability of carboplatin-resistant SKOV-3 and induced morphological disruptions in a dose- and time-dependent manner. The gene expression profiles indicated a reprogramming pattern of the previously known and unknown genes and transcription factors associated with the action of TCTN3 on carboplatin-resistant SKOV-3 cells. We also confirmed the C. militaris-induced activation of the ATF3/TP53 pathway. Immunoblotting indicated that cotreatment of C. militaris and carboplatin-mediated ATF3/TP53 upregulation induced apoptosis in the carboplatin-resistant SKOV-3 cells, which are involved in the serial activation of pro-apoptotic proteins, including Bcl-2, Bax, caspases, and PARP-1. Further, when the ATF3 and TP53 expression increased, the CHOP and PUMA expressions were upregulated. Consequently, the upregulated CHOP/PUMA expression activated the positive regulation of the apoptotic signaling pathway. In addition, it decreased the Bcl-2 expression, leading to marked ovarian cancer cells sensitive to carboplatin by enhancing apoptosis. We then corroborated these results using in vivo experiments. Taken together, C. militaris inhibits carboplatin-resistant SKOV-3 cell proliferation and induces apoptosis possibly through ATF3/TP53 signaling upregulation and CHOP/PUMA activation. Therefore, our findings provide new insights into the treatment of carboplatin-resistant ovarian cancer using C. militaris.


Blood ◽  
2005 ◽  
Vol 106 (11) ◽  
pp. 1080-1080 ◽  
Author(s):  
H. Jorgensen ◽  
E. Allan ◽  
N. Jordanides ◽  
A. Hamilton ◽  
J. Mountford ◽  
...  

Abstract AMN107 (Novartis) is a novel Abl tyrosine kinase inhibitor specifically developed to be more selective for BcrAbl. AMN107 also maintains activity against the most common mutations associated with clinical resistance to imatinib mesylate (IM). In preclinical studies in cell lines and animal models, AMN107 was found to have greater potency than IM. By 3H-thymidine proliferation assays, the IC50 for AMN107 in K562 cells was 30 +/− 10nM compared with 600 +/− 60nM for IM. AMN107 and IM reduced K562 output cell number to 25% of input at 50 and 1000nM respectively, at 72h. These data are in keeping with the reported 20-fold increase in potency of AMN107 over IM. In addition, we have tested AMN107 for in vitro activity against primary CD34+Ph+ CML cells during 72h of culture in 5 growth factors. In CML cells (n=5), AMN107 and IM failed to reduce input cell number although the total cell output was restricted to 50% of PBS treated control at 2 +/− 1μM for AMN107 and to 31 +/− 7% of PBS treated control for 5μM IM suggesting the drugs were equipotent. The ability of the drugs to inhibit BcrAbl activity was then measured indirectly via the phosphorylation status of CrkL using a specific antiphospho-CrkL antibody and flow cytometry. Once again AMN107 and IM appeared equipotent in CML cells with 5μM of each compound leading to equal de-phosphorylation of CrkL. We next tested the efficacy of AMN107 as a single agent and in combination with IM against quiescent CML cells using in vitro dye (CFSE) tracking experiments. We evaluated by flow cytometry the proportion of input cells remaining alive, CD34+ and undivided (CFSEmax) or in first division. Compared to PBS treated control, 1.7, 2.5, 3.8 and 4.7-fold increases were found in the proportion of input CD34+ cells recovered in divisions 0 and 1 after 3 days exposure to 0.005, 0.05, 0.5 and 5μM AMN107, respectively. This was less accumulation than observed in the IM (5μM)-treated cells (11.0-fold). The combination of IM and AMN107, each at 5μM, was more effective in terms of total cell kill (54 and 74% fewer total cells remaining than with IM and AMN107 alone, respectively) and resulted in fewer viable cells recovered in divisions 0 and 1 than with either agent alone (for the combination, 1.9-fold on PBS treated recovery). We finally assessed the role of ABCG2 in modulating AMN107’s access to its intracellular BcrAbl target. We have previously shown ABCG2 to be over-expressed on CML stem cells and to interact with IM (Blood (2004); 104: 205a). We hypothesised that AMN107 and IM may co-operate as ABCG2 substrates or inhibitors to increase the intracellular levels of either or both drugs thus amplifying their efficacy against target protein specifically in CML stem cells. In competition assays with a known fluorescent substrate of ABCG2 (ie BODIPY-prazosin, BP), a specific inhibitor of the ABCG2 pump (fumitremorgin C, FTC) and an ABCG2 stably transfected AML cell line (AML6.2), the sample treated with BP plus FTC is taken to have greatest retention (100%). AMN107 inhibited efflux in a dose dependent manner to a maximum of 88% at 5μM, similarly to IM. Thus, AMN107 was equipotent with IM in primary CML stem cells in terms of restricting cell growth, inhibiting BcrAbl activity and interacting with ABCG2. However, AMN107 alone lead to less accumulation of quiescent CML cells in vitro as compared to IM, with the combination even more effective in this regard. The apparent co-operative effect of AMN107 and IM at the stem cell level would be predicted to improve clinical responses if tolerated in patients.


2014 ◽  
Vol 220 (3) ◽  
pp. 263-276 ◽  
Author(s):  
Anna Z Szóstek ◽  
António M Galvão ◽  
Graça M Ferreira-Dias ◽  
Dariusz J Skarzynski

This study aimed to evaluate the influence of ovarian steroids on equine endometrial epithelial and stromal cells, specifically i) prostaglandin (PG) production in a time-dependent manner, ii) specific PG synthases mRNA transcription and protein expression, and iii) cell proliferation. After passage I, cells were exposed to vehicle, oxytocin (OT, positive control, 10−7M), progesterone (P4, 10−7M), 17β estradiol (E2, 10−9M), or P4+E2for 12, 24, 48, or 72 h. Following treatment, PG concentration was determined using the direct enzyme immunoassay (EIA) method. Alterations inPGsynthases mRNA transcriptions,PGsynthases protein expression, and cell proliferation in response to the treatments were determined after 24 h using real-time PCR, western blot, or 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide respectively. After 24 h, E2and P4+E2increased PGE2and PGF2αsecretion as well as specific prostaglandin-endoperoxide synthase-2 (PTGS2), PGE2synthases (PGES), and PGF2αsynthases (PGFS) expression in the epithelial cells (P<0.05). Additionally, E2and P4+E2increased PTGS2 expression in stromal cells after 24 h (P<0.05). In stromal cells, P4+E2increased PGE2production as well as PGES expression after 24 h (P<0.05). Both E2and P4+E2increased PGF2αproduction by stromal cells after 24 h (P<0.05). Ovarian steroids affected proliferation of stromal and epithelial cells during the 24-h incubation period (P<0.05). We provide evidence that ovarian steroids affect PG production in equine endometrial cells, upregulating PTGS2, PGES, and PGFS expression. Ovarian steroid-stimulated PG production could be an important mechanism occurring in the equine endometrium that is involved in the regulation of the estrous cycle and early pregnancy.


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