Effect of human papillomavirus (HPV) 16 E6 and E7 gene silencing on epidermal growth factor receptor (EGFR) phosphorylation status in HPV16+oropharyngeal cancer cell lines

2009 ◽  
Vol 27 (15_suppl) ◽  
pp. e17006-e17006
Author(s):  
T. Rampias ◽  
C. Sasaki ◽  
A. Psyrri
Keyword(s):  
Cell Lines ◽  
Cancer Cell ◽  
Oropharyngeal Cancer ◽  
Growth Factor Receptor ◽  
Cancer Cell Lines ◽  
Protein Levels ◽  
E7 Gene ◽  
Epidermal Growth ◽  
E6 And E7 ◽  
Retrovirus Infection

e17006 Background: Aberrant activation of EGFR intrinsic tyrosine phosphotransferase activity correlates with poor prognosis in several cancers. In this study, we sought to determine the effect of HPV16 E6 and E7 gene silencing on the status of EGFR phosphorylation in HPV16+ oropharyngeal cancer cell lines. Methods: Short hairpin RNAs targeting HPV type 16 E6 and E7 genes were delivered by retrovirus infection to HPV16+ oropharyngeal cancer cell lines 147T and 090. E6/E7 repression was assessed by quantitative reverse transcription polymerase chain reaction and western blotting for p53 and Rb protein levels 48 hours after retrovirus infection. Phospho-EGFR (Tyr1068), (Tyr845), (Tyr992), (Tyr1045) and total EGFR protein levels before and after silencing were then analyzed by western blotting in 147T and 090 oropharyngeal cancer cell lines. Results: Quantitative RT-PCR analysis showed reduction in E6/E7 mRNA levels up to 85% the level in uninfected or control shRNA infected cell lines. Protein expression revealed substantial downregulation of phospho-EGFR (Tyr992) protein levels, 48 h after the retrovirus infection of 090 and 147T cell lines. A slight reduction of phospho-EGFR (Tyr845) was also observed in both HPV16+ cell lines after silencing. No phosphorylation was detected at sites Y1068 and Y1045 of EGFR. Conclusions: We provide evidence that E6 and E7 are involved in tyrosine phosphorylation of epidermal growth factor receptor at sites Y992 and Y845. Phospho-tyrosine 992 is a direct binding site for the PLCγ SH2 domain and phosphorylation in this site is associated with activation of PLCγ-mediated downstream signaling. Phosphorylation of Tyr845 in the kinase domain is implicated in stabilizing the activation loop maintaining the enzyme in an active state. Since enhanced EGFR activation appears to be a direct consequence of E6/E7 expression, targeting E6/E7 may be effective EGFR blockade in HPV16+oropharyngeal cancers. No significant financial relationships to disclose.

Dual Targeting of the Epidermal Growth Factor Receptor Using the Combination of Cetuximab and Erlotinib: Preclinical Evaluation and Results of the Phase II DUX Study in Chemotherapy-Refractory, Advanced Colorectal Cancer

2012 ◽  
Vol 30 (13) ◽  
pp. 1505-1512 ◽  
Author(s):  
Andrew J. Weickhardt ◽  
Tim J. Price ◽  
Geoff Chong ◽  
Val Gebski ◽  
Nick Pavlakis ◽  
...  
Keyword(s):  
Colorectal Cancer ◽  
Colon Cancer ◽  
Epidermal Growth Factor Receptor ◽  
Cell Lines ◽  
Cancer Cell ◽  
Growth Factor Receptor ◽  
Cancer Cell Lines ◽  
Colon Cancer Cell ◽  
Colon Cancer Cell Lines ◽  
Epidermal Growth

Purpose This preclinical and phase II study evaluated the efficacy and safety of the combination of cetuximab and erlotinib in metastatic colorectal cancer (mCRC). Patients and Methods The activity and mechanism of action of the combination of cetuximab plus erlotinib were investigated in vitro in colorectal cancer cell lines. In the clinical study, patients with chemotherapy-refractory mCRC were treated with cetuximab 400 mg/m2 as a loading dose and then weekly cetuximab 250 mg/m2 with erlotinib 100 mg orally daily. The primary end point was response rate (RR), which was evaluated separately in KRAS wild-type (WT) versus KRAS mutant tumors. Secondary end points included toxicity, progression-free survival (PFS), and overall survival. Target accrual was 50 patients, with a one-stage design. Results Preclinical studies demonstrated synergistic activity of cetuximab and erlotinib cotreatment on growth inhibition of colon cancer cell lines both as a result of enhanced inhibition of the epidermal growth factor receptor pathway and differential effects on STAT3. In the clinical study, 50 patients were enrolled, with 48 patients evaluable for response. The overall RR was 31% (95% CI, 26% to 57%), with a median PFS of 4.6 months (95% CI, 2.8 to 5.6 months). RR was 41% (95% CI, 26% to 57%) in KRAS WT tumors, with a median PFS of 5.6 months (95% CI, 2.9 to 5.6 months). There was no response in 11 patients with KRAS mutations. Frequent grade 3 and 4 toxicities were rash (48%), hypomagnesaemia (18%), and fatigue (10%). Conclusion The combination of cetuximab and erlotinib synergistically inhibits growth of colon cancer cell lines, achieves promising efficacy in patients with KRAS WT mCRC, and merits evaluation in further randomized studies.

Inhibition of MLK3 Decreases Proliferation and Increases Antiproliferative Activity of Epidermal Growth Factor Receptor (EGFR) Inhibitor in pancreatic cancer cell Lines

2010 ◽  
Vol 3 ◽  
pp. CGM.S2824 ◽  
Author(s):  
Sreenivasa R. Chandana ◽  
Cheryl M. Leece ◽  
Kathleen A. Gallo ◽  
Burra V. Madhukar ◽  
Barbara A. Conley
Keyword(s):  
Pancreatic Cancer ◽  
Epidermal Growth Factor Receptor ◽  
Growth Factor ◽  
Cell Lines ◽  
Cancer Cell ◽  
Pancreatic Cancer Cell ◽  
Growth Factor Receptor ◽  
Cancer Cell Lines ◽  
Egfr Inhibitor ◽  
Epidermal Growth

Pancreatic adenocarcinoma is associated with advanced presentation and poor survival. Currently approved therapies have minimal effect on patient survival. Pancreatic adenocarcinomas have a high incidence of activated K-RAS, which may confer resistance to epidermal growth factor receptor (EGFR) inhibitors. Mixed lineage kinase-3 (MLK3) is a MAP3K that activates multiple MAPK pathways. The role of MLK3 in the pathophysiology and resistance to therapy of pancreatic adenocarcinoma has not been investigated. MLK3 is over expressed in pancreatic cancer cell lines compared to an immortalized pancreatic epithelial cell line. The requirement of MLK3 for cell proliferation and survival of pancreatic cancer cell lines, PANC-1 and MiaPaCa-2, was investigated using RNA interference (siRNA) and MLK inhibitor, K252a, alone or in conjunction with the EGFR inhibitor, Compound 56. Ablation of expression of MLK3 via siRNA-mediated gene silencing and pharmacological inhibition of MLK3 by K252a each decreased cell viability in both pancreatic cancer cell lines, with a concurrent decrease in the activation of ERK, JNK and AKT. Concomitant inhibition of EGFR and MLK3 induced apoptosis, as evidenced by increased cleavage of PARP and caspase-3. These results suggest that MLK3 plays an important role in survival and proliferation of pancreatic cancer cell lines and that inhibition of MLK3 may enhance the therapeutic efficacy of EGFR inhibitors in the treatment of pancreatic cancer.

Evaluation of Anticancer and Epidermal Growth Factor Receptor Inhibition Activity by Benzochromeno Pyrimidin Derivatives in Three Human Cancer Cell Lines

2021 ◽  
Vol 18 ◽  
Author(s):  
Razieh Mohammadian ◽  
Sussan Kabudanian Ardestani ◽  
Maliheh Safavi
Keyword(s):  
Nitric Oxide ◽  
Epidermal Growth Factor Receptor ◽  
Cell Lines ◽  
Cancer Cell ◽  
Caspase 3 ◽  
Growth Factor Receptor ◽  
Cancer Cell Lines ◽  
Inhibition Activity ◽  
Egfr Inhibition ◽  
Epidermal Growth

Background: Cancer therapy is one of the most important challenges that human being faces. The abnormal activity of epidermal growth factor receptor tyrosine kinase (EGFR1) in tumors has been reported in many studies. Tyrosine kinase inhibitors are now commercially available for the treatment of a variety of cancers. Based on our previous studies, we assumed that a hybrid of aminopyrimidine derivatives as EGFR inhibitors and benzocheromen derivatives as cytotoxic agents can induce apoptosis in EGFR positive cancer cells. In the present study, the cytotoxic effect, ability of EGFR inhibition and apoptosis induction of some syndfrthetic benzochromene pyrimidine derivatives were investigated on MDA-MB231, SKBR3 and PC3 cell lines. Methods: The EGFR inhibition activity was determined using cell-based EGFR ELISA kit. Cell viability was determined by MTT assay in 2D and 3D cultures. The apoptosis was confirmed through different methods such as fluorescent staining, annexin V– propidium iodide double staining, DNA-Ladder assay, caspase-3 colorimetric assay, and nitric oxide assay. Results: The Results of the MTT assay showed that derivatives with different substituent exhibited differential cytotoxicity in three cancer cell lines, although in MDA-MB231 the cytotoxicity effect of compounds are more obvious than the other cell lines. Production of nitric oxide, caspase-3 activity and DNA-fragmentation was significant in MDA-MB231 and PC3 cells. SKBR3 cells, despite having the lowest apoptosis among these three cell lines, showed a significant EGFR inhibition in the ELISA assay. Conclusion: In this research we proved that hybrids of benzocheromen and amino pyrimidine could be effective on growth inhibition of cancer cell lines and may be used as a drug candidate for cancer therapy in the future.

scholarly journals Restoring E-Cadherin Expression Increases Sensitivity to Epidermal Growth Factor Receptor Inhibitors in Lung Cancer Cell Lines

2006 ◽  
Vol 66 (2) ◽  
pp. 944-950 ◽  
Author(s):  
Samir E. Witta ◽  
Robert M. Gemmill ◽  
Fred R. Hirsch ◽  
Christopher D. Coldren ◽  
Karla Hedman ◽  
...  
Keyword(s):  
Lung Cancer ◽  
Epidermal Growth Factor Receptor ◽  
Growth Factor ◽  
Epidermal Growth Factor ◽  
Cell Lines ◽  
Cancer Cell ◽  
Growth Factor Receptor ◽  
Cancer Cell Lines ◽  
Lung Cancer Cell ◽  
Epidermal Growth

scholarly journals Sensitivity to inhibition of DNA repair by Olaparib in novel oropharyngeal cancer cell lines infected with Human Papillomavirus

PLoS ONE ◽  
2018 ◽  
Vol 13 (12) ◽  
pp. e0207934 ◽  
Author(s):  
Evelyne F. Pirotte ◽  
Stefan Holzhauser ◽  
David Owens ◽  
Stuart Quine ◽  
Ali Al-Hussaini ◽  
...  
Keyword(s):  
Dna Repair ◽  
Human Papillomavirus ◽  
Cell Lines ◽  
Cancer Cell ◽  
Oropharyngeal Cancer ◽  
Cancer Cell Lines
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