scholarly journals Thyroid Cancer Cell Resistance to gefitinib Depends on the Constitutive Oncogenic Activation of the ERK Pathway

2013 ◽  
Vol 98 (6) ◽  
pp. 2502-2512 ◽  
Author(s):  
Francesco Frasca ◽  
Veronica Vella ◽  
Maria Luisa Nicolosi ◽  
Rosa Linda Messina ◽  
Fiorenza Gianì ◽  
...  

Context: Poorly differentiated thyroid carcinomas are refractory to common anticancer therapies, and novel inhibitors are being tested in these deadly malignancies. The epidermal growth factor receptor (EGFR) tyrosine kinase represents an attractive target for treatment because it is up-regulated in thyroid cancer and plays a role in cancer progression. However, EGFR inhibitors have provided poor results in thyroid carcinomas. Objective: We evaluated the possible mechanism underlying the resistance of thyroid cancer cells to EGFR inhibitors. Design: We tested the effect of the EGFR tyrosine kinase inhibitor gefitinib in a panel of thyroid cancer cell lines. Results: We found that in most of the cell lines, although gefitinib inhibited EGFR phosphorylation, it was poorly effective in reducing cell viability. gefitinib, however, was able to inhibit epidermal growth factor-induced cell migration and matrix invasion. In most thyroid cancer cell lines, gefitinib significantly inhibited Akt phosphorylation by inhibiting EGFR activation, but it had limited or no effect on ERK phosphorylation. The poor cell response to gefitinib was associated with genetic alterations, leading to constitutive activation of the ERK pathway, including BRAF(V600E) and HRASG12A/Q61R mutations and RET/PTC1 rearrangement. When BRAF(V600E)-positive thyroid cancer cells were incubated with the specific BRAF inhibitor PLX4032, sensitivity to gefitinib was restored. Similar results were obtained with rat sarcoma and RET/papillary thyroid cancer inhibitors. Conclusions: These results indicate that thyroid cancer resistance to gefitinib is due to the constitutive activation of the mitogenic pathway by either signals downstream of EGFR or other tyrosine kinase receptors. This resistance can be overcome by the combined use of selective inhibitors.

Endocrine ◽  
2021 ◽  
Author(s):  
Changxin Jing ◽  
Yanyan Li ◽  
Zhifei Gao ◽  
Rong Wang

Abstract Purpose Koningic acid (KA), a sesquiterpene lactone, has been identified as an antimicrobial agent. Recent studies have revealed KA’s antitumor activities in colorectal cancer, leukemia, and lung cancer. However, its antitumor effect in thyroid cancer remains largely unknown. Methods The effects of KA on proliferation, colony formation, apoptosis in thyroid cancer cells were assessed by MTT assay and flow cytometry. After KA treatment, the glycolysis ability of thyroid cancer cells was detected by ECAR, and the glycolytic products and relative ATP levels were measured by ELISA. The underlying mechanisms of antineoplastic activity of KA in thyroid cancer were detected by Western blot. Finally, the antineoplastic activity in vivo was observed in Xenograft mouse models. Results KA inhibited the proliferation, colony formation, and increased cell apoptosis in thyroid cancer cell lines in a dose and time-dependent manner. We verified that the glycolysis ability, ATP production, and lactic acid level in thyroid cancer cells had experienced an extensive decrease after KA treatment. In addition, lactic acid, the metabolite of glycolysis, could weaken the effect of KA on its colony formation ability in C643 thyroid cancer cell line. Our data also showed that KA kills thyroid cancer cells by inhibiting the MAPK/ERK pathway and decreasing Bcl-2 level. By contrast with the control group, the growth of xenograft tumor was dramatically inhibited by KA without obvious drug side effects. Conclusion Our data demonstrate that KA kills thyroid cancer cell lines by inhibiting their glycolysis ability, the MAPK/ERK pathway and the Bcl-2 level and suggest that KA has potential clinical value in thyroid cancer therapy.


2001 ◽  
Vol 169 (2) ◽  
pp. 417-424 ◽  
Author(s):  
M Iitaka ◽  
S Kakinuma ◽  
S Fujimaki ◽  
I Oosuga ◽  
T Fujita ◽  
...  

Zinc at concentrations of 150, microM or higher induced necrosis as well as apoptosis in thyroid cancer cell lines. Necrosis was induced by zinc in a dose-dependent manner, whereas apoptosis did not increase at higher concentrations of zinc. The expression of the antiapoptotic protein phosphorylated Bad was markedly increased, whereas the expression of the proapoptotic proteins Bax and Bad decreased following Zn(2+) exposure. Zn(2+) induced rapid degradation of IkappaB, and an increase in the binding of nuclear transcription factor-kappaB (NF-kappaB). These observations indicate that antiapoptotic pathways were activated in thyroid cancer cells following exposure to Zn(2+). This may be a self-defence mechanism against apoptosis and may underlie the general resistance of thyroid cancer cells to apoptotic stimuli. Zinc may be a potential cytotoxic agent for the treatment of thyroid cancer.


2018 ◽  
Vol 19 (7) ◽  
pp. 2077 ◽  
Author(s):  
Sabine Wächter ◽  
Annette Wunderlich ◽  
Brandon Greene ◽  
Silvia Roth ◽  
Moritz Elxnat ◽  
...  

Background: The MEK (mitogen-activated protein kinase)–inhibitor selumetinib led to increased radioiodine uptake and retention in a subgroup of patients suffering from radioiodine refractory differentiated thyroid cancer (RR-DTC). We aimed to analyse the effect of selumetinib on the expression of sodium iodide symporter (NIS; SLC5A5) and associated miRNAs in thyroid cancer cells. Methods: Cytotoxicity was assessed by viability assay in TPC1, BCPAP, C643 and 8505C thyroid cancer cell lines. NIS, hsa-let-7f-5p, hsa-miR-146b-5p, and hsa-miR-146b-3p expression was determined by quantitative RT-PCR. NIS protein was detected by Western blot. Radioiodine uptake was performed with a Gamma counter. Results: Selumetinib caused a significant reduction of cell viability in all thyroid cancer cell lines. NIS transcript was restored by selumetinib in all cell lines. Its protein level was found up-regulated in TPC1 and BCPAP cells and down-regulated in C643 and 8505C cells after treatment with selumetinib. Treatment with selumetinib caused a down-regulation of hsa-let-7f-5p, hsa-miR-146b-5p and hsa-miR-146b-3p in TPC1 and BCPAP cells. In 8505C cells, a stable or down-regulated hsa-miR-146b-5p was detected after 1h and 48h of treatment. C643 cells showed stable or up-regulated hsa-let-7f-5p, hsa-miR-146b-5p and hsa-miR-146b-3p. Selumetinib treatment caused an increase of radioiodine uptake, which was significant in TPC1 cells. Conclusions: The study shows for the first time that selumetinib restores NIS by the inhibition of its related targeting miRNAs. Further studies are needed to clarify the exact mechanism activated by hsa-miR-146b-5p, hsa-miR-146b-3p and hsa-let7f-5p to stabilise NIS. Restoration of NIS could represent a milestone for the treatment of advanced RR-DTC.


2011 ◽  
Vol 211 (1) ◽  
pp. 79-85 ◽  
Author(s):  
Hyun-Jeung Choi ◽  
Tae Yong Kim ◽  
Namhyun Chung ◽  
Ji Hye Yim ◽  
Won Gu Kim ◽  
...  

5-Aminoimidazole-4-carboxamide-ribonucleoside (AICAR) is an activator of 5′-AMP-activated protein kinase (AMPK), which plays a role in the maintenance of cellular energy homeostasis. Activated AMPK inhibits the protein kinase mechanistic target of rapamycin, thereby reducing the extent of protein translation and suppressing both cell growth and cell cycle entry. Recent reports indicate that AMPK-mediated growth inhibition is achieved via an action of the RAF–MEK–ERK mitogen-activated protein kinase pathway in melanoma cells harboring the V600E mutant form of the BRAF oncogene. In this study, we investigated the anti-cancer efficacy of AICAR by measuring its effects on proliferation, apoptosis, and cell cycle progression of BRAF wild-type and V600E-mutant thyroid cancer cell lines. We also explored the mechanism underlying these effects. AICAR inhibited the proliferation of BRAF V600E-mutant thyroid cancer cell lines more strongly than was the case with wild-type cell lines. The suppressive effect of AICAR on cell proliferation was associated with increased S-phase cell cycle arrest and apoptosis. Interestingly, AICAR suppressed phosphorylation of ERK and p70S6K in BRAF V600E-mutant thyroid cancer cells, but rather increased phosphorylation in wild-type cells. Together, the results indicate that AICAR-induced AMPK activation in BRAF V600E-mutant thyroid cancer cell lines resulted in increases in apoptosis and S-phase arrest via downregulation of ERK and p70S6K activity. Thus, regulation of AMPK activity may be potentially useful as a therapy for thyroid cancer if the cancer harbors a BRAF V600E mutation.


2010 ◽  
Vol 24 (11) ◽  
pp. 2241-2242
Author(s):  
Abdul K. Siraj ◽  
Azhar R. Hussain ◽  
Maha Al-Rasheed ◽  
Maqbool Ahmed ◽  
Prashant Bavi ◽  
...  

Abstract Context: TMS1 is a tumor suppressor gene that encodes for caspase recruitment domain containing regulatory protein and has been shown to be hypermethylated in various cancers. However, its methylation status has not been investigated in thyroid cancer. Therefore, we studied the methylation of TMS1 and its functional consequence in thyroid cancer. Design: The methylation status of the promoter region of the TMS1 gene was determined using methylation-specific PCR in 40 papillary thyroid cancer samples, 10 normal thyroid tissue, and seven thyroid cancer cell lines. RT-PCR and Western blot analysis were used to assess the expression levels. 5-aza-2′-deoxycytidine was used to demethylate the thyroid cancer cell lines. Cell viability and apoptosis was determined by dimethylthiazoldiphenyltetra-zoliumbromide and flow cytometry. Results: Twenty-three percent of the papillary thyroid carcinoma samples were found to be methylated for the TMS1 gene. Two of seven thyroid cell lines were either completely or partially methylated for the TMS1 gene. The treatment of methylated thyroid cancer cell lines with 5-aza-2′-deoxycytidine resulted in the demethylation of the TMS1 gene leading to the restoration of its expression. After demethylation, treatment of cells with TNF-related apoptosis-inducing ligand (TRAIL) led to the induction of apoptosis via activation of caspases-8, caspase-3, and poly(ADP-ribose) polymerase. Interestingly, gene silencing of TMS1 using TMS1-specific small interfering RNA prevented TRAIL-mediated apoptosis. Conclusion: Our results demonstrated that the TMSI gene is methylated in thyroid cancer cells and repression of methylation by 5-aza-2′-deoxycytidine restored expression of the TMS1 gene and sensitized cells to TRAIL-induced apoptosis. These findings suggest that the TMS1 gene can be targeted by combination of demethylating agents with TRAIL to induce efficient apoptosis in thyroid cancer cells.


2016 ◽  
Vol 2016 ◽  
pp. 1-7 ◽  
Author(s):  
Mario Rotondi ◽  
Francesca Coperchini ◽  
Oriana Awwad ◽  
Patrizia Pignatti ◽  
Christian A. Di Buduo ◽  
...  

CXCL8 displays several tumor-promoting effects. Targeting and/or lowering CXCL8 concentrations within the tumor microenvironment would produce a therapeutic benefit. Aim of this study was to test the effect of IFNγon the basal and TNFα-stimulated secretion of CXCL8 in TCP-1 and BCPAP thyroid cancer cell lines (harboring RET/PTC rearrangement and BRAF V600e mutation, resp.). Cells were incubated with IFNγ(1, 10, 100, and 1000 U/mL) alone or in combination with TNF-α(10 ng/mL) for 24 hours. CXCL8 and CXCL10 concentrations were measured in the cell supernatants. IFNγinhibited in a dose-dependent and significant manner both the basal (ANOVAF: 22.759;p<0.00001) and the TNFα-stimulated (ANOVAF: 15.309;p<0.00001) CXCL8 secretions in BCPAP but not in TPC-1 cells (NS). On the other hand, IFNγand IFNγ+ TNF-αinduced a significant secretion of CXCL10 in both BCPAP (p<0.05) and TPC-1 (p<0.05) cells. Transwell migration assay showed that (i) CXCL8 increased cell migration in both TPC-1 and BCPAP cells; (ii) IFNγsignificantly reduced the migration only of BCPAP cells; and (iii) CXCL8 reverted the effect of IFNγ. These results constitute the first demonstration that IFNγinhibits CXCL8 secretion and in turn the migration of a BRAF V600e mutated thyroid cell line.


2006 ◽  
Vol 114 (S 1) ◽  
Author(s):  
B Trojanowicz ◽  
Z Chen ◽  
J Bialek ◽  
Y Radestock ◽  
S Hombach-Klonisch ◽  
...  

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