Click
here to close Hello! We notice that
you are using Internet Explorer, which is not supported by Echinobase
and may cause the site to display incorrectly. We suggest using a
current version of Chrome,
FireFox,
or Safari.
Oncol Lett
2015 Dec 01;106:3385-3392. doi: 10.3892/ol.2015.3740.
Show Gene links
Show Anatomy links
EML4-ALK translocation is associated with early onset of disease and other clinicopathological features in Chinese female never-smokers with non-small-cell lung cancer.
Ren W
,
Zhang BO
,
Ma J
,
Li W
,
Lan J
,
Men H
,
Zhang Q
.
Abstract
Non-small-cell lung cancer (NSCLC) with echinoderm microtubule-associated protein-like 4-anaplastic lymphoma kinase (EML4-ALK) translocation is resistant to epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs), including gefitinib and erlotinib, but responds to the ALK-TKI crizotinib. Characterization of EML4-ALK translocation may provide invaluable information to facilitate disease diagnosis and improve the outcome of customized treatment. Although the occurrence of EML4-ALK translocation is likely to be affected by the smoking habits and gender of patients, the translocation has not been characterized extensively in female never-smokers with NSCLC. Therefore, 280 female never-smokers that were diagnosed with NSCLC were enrolled in the present study, and characteristics of EML4-ALK translocation, including the frequency, were determined in these NSCLC patients. EML4-ALK fusion variants were detected using Multiplex one-step reverse transcription-polymerase chain reaction and subsequently confirmed by DNA sequencing and Vysis ALK Break Apart fluorescence in situ hybridization analysis. The EML4-ALK fusion variants were detected in 21 carcinoma tissue specimens, accounting for 7.5% of the enrolled patients. Out of these patients with EML4-ALK fusion variants, EML4-ALK fusion variant 1 was identified in 12 patients, indicating that variant 1 is the most common type of EML4-ALK fusion gene in the present cohort of patients. ALK mRNA was aberrantly expressed in all the tissues with EML4-ALK translocation, but not in the carcinoma tissues without EML4-ALK translocation. In addition, the EML4-ALK translocation was more frequently found in younger patients. The median age of patients with EML4-ALK translocation was 50.95±2.29 years, which was significantly younger (P<0.01) than the median age of the patients without EML4-ALK translocation (57.15±0.56). The EML4-ALK translocation was detected exclusively in undifferentiated tumors that were graded as poorly- or moderately-differentiated carcinomas and suspected to be more malignant compared with well-differentiated tumors. In summary, the present study found that 7.5% of patients with NSCLC that are female never-smokers harbor EML4-ALK translocations, which are associated with the aberrant expression of ALK mRNA, early onset of disease and undifferentiated carcinomas.
Figure 1. Screening for EML4-ALK fusion transcripts in the tissues obtained from female never-smokers with non-small cell lung cancer. (A) Representative DNA gel images revealing the expression of the EML4-ALK fusion transcript variants V1, V3a, V3b, V4a, V5a and E17-20, and ABL controls, as determined by Multiplex one-step reverse transcription-polymerase chain reaction. (B) ALK Break Apart fluorescence in situ hybridization analysis revealed ALK inversion in carcinoma tissues. Two probes targeting the sequences prior to and following the breaking point were labeled by red and green fluorescent dye, respectively. Representative images of EML4-ALK-negative (left) and -positive (right) carcinomas are shown. The ALK inversion in EML4-ALK-positive carcinomas is indicated by two separated red and green dots (right) located at least two signal diameters apart. NC, negative case; M, DNA ladder; EML4-ALK, echinoderm microtubule-associated protein-like 4-anaplastic lymphoma kinase; ABL, Abelson murine leukemia viral oncogene homolog.
Figure 2. EML4-ALK fusion transcript variants in female never-smokers with non-small cell lung cancer. (A) Representative DNA sequencing chromatographs and schematic drawings revealing EML4-ALK fusion junctions. Five representative EML4-ALK fusion transcript variants were detected by Multiplex reverse transcription-polymerase chain reaction. The sequences and variant types were determined by direct DNA sequencing. The 5 detected EML4-ALK fusion variants consisted of V1, V3a/3b, V4a, V5a and E17-20. Variant 2 was not detected in the present cohort of patients. Schematic drawings are exhibited below the corresponding DNA sequences to indicate the organization of fusion junctions. (B) Pie graph showing the frequency of EML4-ALK fusion variants. A total of 5 different EML4-ALK fusion variants were detected, consisting of V1, V3a/3b, V4a, V5a, and E17-20. The number and the percent of each variant are indicated in the graph. Variant 2 was not detected in these carcinoma tissues. EML4-ALK, echinoderm microtubule-associated protein-like 4-anaplastic lymphoma kinase.
Figure 3. Aberrant expression of ALK mRNA and protein. (A) Scatter graph demonstrating that the expression of ALK mRNA is significantly higher (P<0.0001) in carcinoma tissues harboring EML4-ALK fusion compared with tissues without the fusion gene in female never-smokers with non-small cell lung cancer. The values are expressed as the mean ± standard error of the mean. (B) Representative images exhibiting the immunohistochemical staining for ALK in carcinoma tissues. The ALK protein was aberrantly expressed in carcinoma tissues harboring the EML4-ALK fusion gene (EML4-ALK+), but ALK protein expression was absent in tissues without the EML4-ALK fusion gene (EML4-ALK-). EML4-ALK, echinoderm microtubule-associated protein-like 4-anaplastic lymphoma kinase.
Figure 4. Summary of the median age of ALK+ and ALK- patients and the two combined. The median age in ALK+ was significantly lower compared with the median age in ALK- patients or in the two groups combined. The values are expressed as the mean ± standard error of the mean. *P<0.05 and **P<0.01. EML4-ALK, echinoderm microtubule-associated protein-like 4-anaplastic lymphoma kinase; ALK+, patients harboring EML4-ALK fusion; ALK-, patients without EML4-ALK fusion.
Boland,
Anaplastic lymphoma kinase immunoreactivity correlates with ALK gene rearrangement and transcriptional up-regulation in non-small cell lung carcinomas.
2009, Pubmed
Boland,
Anaplastic lymphoma kinase immunoreactivity correlates with ALK gene rearrangement and transcriptional up-regulation in non-small cell lung carcinomas.
2009,
Pubmed
Camidge,
Activity and safety of crizotinib in patients with ALK-positive non-small-cell lung cancer: updated results from a phase 1 study.
2012,
Pubmed
Choi,
Identification of novel isoforms of the EML4-ALK transforming gene in non-small cell lung cancer.
2008,
Pubmed
Inamura,
EML4-ALK fusion is linked to histological characteristics in a subset of lung cancers.
2008,
Pubmed
,
Echinobase
Inamura,
EML4-ALK lung cancers are characterized by rare other mutations, a TTF-1 cell lineage, an acinar histology, and young onset.
2009,
Pubmed
,
Echinobase
Jemal,
Global cancer statistics.
2011,
Pubmed
Kohno,
KIF5B-RET fusions in lung adenocarcinoma.
2012,
Pubmed
Koivunen,
EML4-ALK fusion gene and efficacy of an ALK kinase inhibitor in lung cancer.
2008,
Pubmed
Kwak,
Anaplastic lymphoma kinase inhibition in non-small-cell lung cancer.
2010,
Pubmed
Li,
Clinical significance of EML4-ALK fusion gene and association with EGFR and KRAS gene mutations in 208 Chinese patients with non-small cell lung cancer.
2013,
Pubmed
Lin,
Exon array profiling detects EML4-ALK fusion in breast, colorectal, and non-small cell lung cancers.
2009,
Pubmed
,
Echinobase
Lynch,
Activating mutations in the epidermal growth factor receptor underlying responsiveness of non-small-cell lung cancer to gefitinib.
2004,
Pubmed
Martelli,
EML4-ALK rearrangement in non-small cell lung cancer and non-tumor lung tissues.
2009,
Pubmed
,
Echinobase
Paez,
EGFR mutations in lung cancer: correlation with clinical response to gefitinib therapy.
2004,
Pubmed
Petty,
Gene expression profiling in non-small cell lung cancer: from molecular mechanisms to clinical application.
2004,
Pubmed
Pomerleau,
Defining a never-smoker: results from the nonsmokers survey.
2004,
Pubmed
Rikova,
Global survey of phosphotyrosine signaling identifies oncogenic kinases in lung cancer.
2007,
Pubmed
Sasaki,
The biology and treatment of EML4-ALK non-small cell lung cancer.
2010,
Pubmed
,
Echinobase
Schiller,
Comparison of four chemotherapy regimens for advanced non-small-cell lung cancer.
2002,
Pubmed
Shaozhang,
Detection of EML4-ALK fusion genes in non-small cell lung cancer patients with clinical features associated with EGFR mutations.
2012,
Pubmed
Shaw,
Clinical features and outcome of patients with non-small-cell lung cancer who harbor EML4-ALK.
2009,
Pubmed
Shaw,
Effect of crizotinib on overall survival in patients with advanced non-small-cell lung cancer harbouring ALK gene rearrangement: a retrospective analysis.
2011,
Pubmed
Shaw,
Crizotinib versus chemotherapy in advanced ALK-positive lung cancer.
2013,
Pubmed
Shinmura,
EML4-ALK fusion transcripts, but no NPM-, TPM3-, CLTC-, ATIC-, or TFG-ALK fusion transcripts, in non-small cell lung carcinomas.
2008,
Pubmed
Smith,
The care of the lung cancer patient in the 21st century: a new age.
2004,
Pubmed
Soda,
Identification of the transforming EML4-ALK fusion gene in non-small-cell lung cancer.
2007,
Pubmed
,
Echinobase
Solomon,
First-line crizotinib versus chemotherapy in ALK-positive lung cancer.
2014,
Pubmed
Takahashi,
Clinicopathologic features of non-small-cell lung cancer with EML4-ALK fusion gene.
2010,
Pubmed
,
Echinobase
Takeuchi,
KIF5B-ALK, a novel fusion oncokinase identified by an immunohistochemistry-based diagnostic system for ALK-positive lung cancer.
2009,
Pubmed
Thunnissen,
EML4-ALK testing in non-small cell carcinomas of the lung: a review with recommendations.
2012,
Pubmed
Wong,
A novel KIF5B-ALK variant in nonsmall cell lung cancer.
2011,
Pubmed
,
Echinobase
Wong,
The EML4-ALK fusion gene is involved in various histologic types of lung cancers from nonsmokers with wild-type EGFR and KRAS.
2009,
Pubmed
,
Echinobase
Zhang,
Fusion of EML4 and ALK is associated with development of lung adenocarcinomas lacking EGFR and KRAS mutations and is correlated with ALK expression.
2010,
Pubmed
