Characterization of human FcεRIα chain expression and gene copy number in humanized rat basophilic leukaemia (RBL) reporter cell lines

6063 Background: EGFR gene copy number has previously been reported to predict for improved overall survival in NSCLC patients treated with gefitinib (IRESSA) or erlotinib compared with placebo [JCO 2006;24:5034–42 & N Engl J Med 2005;353:133–44]. The utility of EGFR gene copy number as a predictive biomarker in other tumour types such as squamous cell carcinoma of the head and neck (SCCHN) is currently under clinical investigation. The present study examined a panel of 20 SCCHN cell lines to identify potential biomarkers predicting in vitro sensitivity to EGFR tyrosine kinase inhibitors (TKIs). Methods: A panel of 20 SCCHN cell lines was screened for sensitivity to gefitinib, vandetanib or erlotinib using a viable cell number endpoint, with G150 values determined for each cell line (inhibitor concentration required to give 50% growth inhibition). Cell lines were blinded and assessed for EGFR, HER2 and HER3 protein expression by ELISA, mutation status by dye-terminator sequencing, and gene copy number by fluorescence in situ hybridisation (FISH). Results: A broad range in sensitivity was observed for all compounds across the panel of 20 SCCHN cell lines (G150 ranging from 0.001uM to =10uM). 12 cell lines were positive for EGFR genomic gain. Sensitivity (GI50 <1uM) to all EGFR TKIs was seen in 11 lines and resistance (GI50 >8uM) in 5 lines. Of the sensitive cell lines, 9 were positive for EGFR genomic gain compared with only 1 of the resistant lines. Furthermore, EGFR protein expression also had a direct association with EGFR TKI sensitivity. In contrast, only 4 cell lines were positive for HER2 or HER3 genomic gain and there was no correlation with sensitivity. The most sensitive cell line was positive for EGFR genomic gain and was the only line to have an EGFR TK mutation (S768I in exon 20). Conclusions: EGFR gene copy number and protein expression appeared to have predictive value in identifying SCCHN cell lines sensitive to EGFR TKIs. No significant financial relationships to disclose.

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The synthesis of ribosomal proteins S16 and L32 is not autogenously regulated during mouse myoblast differentiation

Molecular and Cellular Biology ◽

10.1128/mcb.7.12.4464-4471.1987 ◽

1987 ◽

Vol 7 (12) ◽

pp. 4464-4471

Author(s):

L H Bowman

Keyword(s):

Cell Lines ◽

Rna Processing ◽

Copy Number ◽

Ribosomal Proteins ◽

Protein Gene ◽

Gene Copy Number ◽

Gene Copy ◽

Myoblast Differentiation ◽

Myoblast Cell ◽

Mouse Myoblast

A series of mouse myoblast cell lines was constructed that contain 1 to 34 extra copies of either the S16 or the L32 ribosomal protein (r-protein) gene. The metabolism of the S16 and L32 r-proteins and mRNAs was examined in myoblasts and fibers of these cell lines to determine whether the synthesis of these r-proteins is autogenously regulated. The incorporation of extra copies of these r-protein genes into the genome resulted in the accumulation of the corresponding mRNAs to levels that were directly proportional to the gene copy number. The levels of the overproduced mRNAs decreased after the differentiation of mouse myoblasts into fibers in parallel to the decrease in the levels of the endogenous r-protein mRNAs. These results indicate that the synthesis of these r-proteins is not autogenously regulated at the level of transcription, RNA processing, or mRNA stability. To determine whether the synthesis of these r-proteins is regulated at the level of translation, the translational efficiencies of the overproduced mRNAs were inferred from their distribution in polysomal gradients. The translational efficiencies of these overproduced r-protein mRNAs in myoblasts are similar to those of the endogenous r-protein mRNAs. After myoblast differentiation, the translational efficiencies of the overproduced r-protein mRNAs decrease exactly like those of the endogenous r-protein mRNAs. Examination of the synthesis and stability of r-proteins in one of the L32-overproducing cell lines demonstrated that the overproduced L32 r-protein degrades shortly after its synthesis. The synthesis and stability of the other r-proteins were unaffected in this cell line. Thus, the synthesis of S16 and L32 r-proteins is not autogenously regulated at any level in either myoblasts or fibers.

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Abstract 1715: High ALK gene copy number as a predictor of response to crizotinib in non-small cell lung cancer cell lines

10.1158/1538-7445.am2012-1715 ◽

2012 ◽

Cited By ~ 1

Author(s):

Khadija Kalai ◽

David Planchard ◽

Nathalie Auger ◽

Frederic Commo ◽

Nicolas Dorvault ◽

...

Keyword(s):

Lung Cancer ◽

Small Cell Lung Cancer ◽

Cell Lines ◽

Cancer Cell ◽

Copy Number ◽

Gene Copy Number ◽

Small Cell ◽

Gene Copy ◽

Lung Cancer Cell ◽

Small Cell Lung

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Characterization of the Pacific salmon gonadotropin-releasing hormone gene, copy number and transcription start site

Molecular and Cellular Endocrinology ◽

10.1016/0303-7207(95)03675-w ◽

1995 ◽

Vol 115 (1) ◽

pp. 113-122 ◽

Cited By ~ 20

Author(s):

Imogen R. Coe ◽

Kristian R. von Schalburg ◽

Nancy M. Sherwood

Keyword(s):

Transcription Start Site ◽

Copy Number ◽

Pacific Salmon ◽

Gene Copy Number ◽

Gonadotropin Releasing Hormone ◽

Gene Copy ◽

Start Site ◽

Transcription Start ◽

The Pacific

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The synthesis of ribosomal proteins S16 and L32 is not autogenously regulated during mouse myoblast differentiation.

Molecular and Cellular Biology ◽

10.1128/mcb.7.12.4464 ◽

1987 ◽

Vol 7 (12) ◽

pp. 4464-4471 ◽

Cited By ~ 19

Author(s):

L H Bowman

Keyword(s):

Cell Lines ◽

Rna Processing ◽

Copy Number ◽

Ribosomal Proteins ◽

Protein Gene ◽

Gene Copy Number ◽

Gene Copy ◽

Myoblast Differentiation ◽

Myoblast Cell ◽

Mouse Myoblast

A series of mouse myoblast cell lines was constructed that contain 1 to 34 extra copies of either the S16 or the L32 ribosomal protein (r-protein) gene. The metabolism of the S16 and L32 r-proteins and mRNAs was examined in myoblasts and fibers of these cell lines to determine whether the synthesis of these r-proteins is autogenously regulated. The incorporation of extra copies of these r-protein genes into the genome resulted in the accumulation of the corresponding mRNAs to levels that were directly proportional to the gene copy number. The levels of the overproduced mRNAs decreased after the differentiation of mouse myoblasts into fibers in parallel to the decrease in the levels of the endogenous r-protein mRNAs. These results indicate that the synthesis of these r-proteins is not autogenously regulated at the level of transcription, RNA processing, or mRNA stability. To determine whether the synthesis of these r-proteins is regulated at the level of translation, the translational efficiencies of the overproduced mRNAs were inferred from their distribution in polysomal gradients. The translational efficiencies of these overproduced r-protein mRNAs in myoblasts are similar to those of the endogenous r-protein mRNAs. After myoblast differentiation, the translational efficiencies of the overproduced r-protein mRNAs decrease exactly like those of the endogenous r-protein mRNAs. Examination of the synthesis and stability of r-proteins in one of the L32-overproducing cell lines demonstrated that the overproduced L32 r-protein degrades shortly after its synthesis. The synthesis and stability of the other r-proteins were unaffected in this cell line. Thus, the synthesis of S16 and L32 r-proteins is not autogenously regulated at any level in either myoblasts or fibers.

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