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Cancer Research 68, 2106, April 1, 2008. doi: 10.1158/0008-5472.CAN-07-5211
© 2008 American Association for Cancer Research
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Molecular Biology, Pathobiology, and Genetics

Epidermal Growth Factor Receptor Gene Amplification Is Acquired in Association with Tumor Progression of EGFR-Mutated Lung Cancer

Yasushi Yatabe1, Takashi Takahashi3 and Tetsuya Mitsudomi2

Departments of 1 Pathology and Molecular Diagnostics and 2 Thoracic Surgery, Aichi Cancer Center; and 3 Division of Molecular Carcinogenesis, Center for Neurological Diseases and Cancer, Nagoya University Graduate School of Medicine, Nagoya, Japan

Requests for reprints: Yasushi Yatabe, Department of Pathology and Molecular Diagnostics, Aichi Cancer Center Hospital, Kanokoden, Chikusa-ku, Nagoya 464-8681, Japan. Phone: 81-52-762-2983; Fax: 81-52-763-5233; E-mail: yyatabe{at}aichi-cc.jp.


   Abstract
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 Abstract
Introduction
 Materials and Methods
 Results
 Discussion
 References
 
Both mutation and amplification of epidermal growth factor receptor (EGFR) in lung cancers have been reported in association with clinical responses to tyrosine kinase inhibitors. We have reported evidence implicating mutation specifically in the "terminal respiratory unit" type of adenocarcinoma, which is characterized by expression of thyroid transcription factor 1, a lineage marker of peripheral airway cells. However, little is known about the role of gene amplification in the molecular progression of lung adenocarcinoma. In this study, we examined the topographical distribution of amplification in three microdissected portions each of 48 individual lung cancers with confirmed mutations. Relative copy number of the gene was analyzed using Taq Man–based gene dosage analysis and fluorescent in situ hybridization technique. Gene amplification was found in 11 lung cancers. Strikingly, nine of the cancers showed heterogeneous distribution, and amplification was associated with higher histologic grade or invasive growth. Because it was likely that the high-grade lesions were the origin for metastases, metastatic lymph nodes corresponding to five tumors with heterogeneous distribution were analyzed. Unexpectedly, amplification status of the metastatic sites was not always associated with gene amplification of the primary tumors, suggesting that selection of the metastatic clone may be defined by other factors. We also examined 17 precursor lesions and 21 in situ lung adenocarcinomas, and found that only one in situ carcinoma harbored gene amplification. Taken together, our results show that mutation occurs early in the development of lung adenocarcinoma, and that amplification may be acquired in association with tumor progression. [Cancer Res 2008;68(7):2106–11]


   Introduction
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 Abstract
 Introduction
Materials and Methods
 Results
 Discussion
 References
 
Epidermal growth factor receptor (EGFR) mutations are correlated with a subset of non–small cell lung cancers, along with specific characteristics such as nonsmoking status, adenocarcinoma histology, being female, and of East Asian ethnicity (1, 2). EGFR mutations are clinically relevant for making treatment decisions (3); they are closely associated with a high response rate for the treatment with EGFR tyrosine kinase inhibitors. However, the association of the mutation with the response and survival has not been confirmed in clinical trials. On the other hand, findings from several clinical trials have indicated that EGFR gene copy number is a better response predictor than mutation status (4–7). In such studies, high polysomy, defined as the presence of >40% of tetraploid cells, along with gene amplification, is regarded as significant gene alteration, although the biological role of high polysomy has not been elucidated. Interestingly, EGFR amplification is closely associated with EGFR mutation. Takano et al. (8) described 13 tumors with gene copy number more than six harbored gene mutations, and Cappuzzo et al. (9) reported that all of the examined tumors with gene amplification were EGFR mutated.

MET is a receptor tyrosine kinase similar to EGFR, and germline mutations at 7q31 have been detected in patients with hereditary papillary renal carcinoma (10). Hereditary papillary renal carcinoma is cytogenetically characterized by trisomy of chromosome 7, for which duplication of the mutant allele is nonrandomly selected (11). In terms of EGFR mutation, a single mutant signal of sequencing electropherograms in some tumors suggested that a nonrandom increase in the number of the EGFR mutant allele caused the amplification (12–14), similar to increases in mutated MET gene copies. This was confirmed in a single case with fluorescent in situ hybridization (FISH) and sequencing, as reported by Ma et al. (15).

Thus, a convergence of evidence suggests that EGFR mutation and amplification are closely associated. However, little is known about EGFR mutation and its relationship with the molecular pathogenesis of lung adenocarcinoma. Therefore, in this study, we examined EGFR amplification in lung cancers with EGFR mutations, using both FISH and Taq Man–based gene dosage analyses. We further addressed whether EGFR amplification was associated with tumor progression and metastasis.


   Materials and Methods
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 Materials and Methods
Results
 Discussion
 References
 
Patients. A total of 48 patients with EGFR gene mutations were selected for this study, including 47 with adenocarcinoma and one with adenosquamous carcinoma. A KRAS mutation was not detected in any of these tumors, which is in accordance with previous reports (13, 16, 17). To address the role of EGFR mutation, EGFR amplification and KRAS mutation in association with schema of lung cancer progression, 107 lesions were examined. These comprised 17 precancerous lesions (atypical adenomatous hyperplasia; AAH), 21 in situ adenocarcinomas (bronchioloalveolar carcinoma), 23 minimally invasive adenocarcinomas, and 46 invasive adenocarcinomas with subsequent recurrence. Some of these data have been published previously (18). Clinicopathologic data were obtained from patient records at the Department of Pathology and Molecular Diagnostics at the Aichi Cancer Center in Nagoya, Japan. For this analysis, written informed consent was obtained from each patient according to the protocol approved by the Institutional Review Board.

Mutational analysis of the EGFR tyrosine kinase domain. EGFR mutation analysis was performed as previously described (16). Briefly, frozen tissue from tumor specimens was grossly dissected into extraction solution, followed by total RNA extraction using an RNeasy kit (Qiagen). The EGFR tyrosine kinase domain (exons 18–24) was amplified by reverse transcription-PCR (SuperScript One-Step RT-PCR System with Platinum Taq DNA Polymerase; Invitrogen), and the products were directly sequenced using an ABI PRISM 310 Genetic Analyzer (Applied Biosystems). The primer sequences were as follows: forward, 5'-AGTCATGGGAGAAAACAACACC-3' and reverse, 5'-ATCCCCCTGAATGACAAGGTAG-3'. For the analysis of small portions of paraffin sections, the Cycleave PCR technique and fragment analysis were applied. This method has also been previously described in detail (19). The Cycleave PCR technique was also used for mutational analysis of KRAS.

Analysis of EGFR gene amplification. To examine the topographical distribution of EGFR amplification, we obtained paraffin sections containing both tumor and normal lung tissue. Three independent portions from each tumor were selected to reflect the morphologic characteristics. DNA was extracted from microdissected tissue and used as a template for Taq Man–based gene dosage using Taq Man Universal PCR Master Mix (Applied Biosystems) according to the manufacturer's instructions. The primer and probe sequences used for gene copy analysis of EGFR are as follows: 5'-ACTGGAAAAAACTGTTTGGGACCT-3' (forward primer), 5'-AGCTGTTTTCACCTCTGTTGCTTAT-3' (reverse primer), and 5'-CCGGTCAGAAAACCA-3' (MGB probe). Fold increase in copy number was calculated as the ratio of the EGFR signal to control gene signals (COG5 and POP7), normalized to the corresponding normal lung tissue in the same section. The primer and probe sequences of these control genes were as follows: for COG5, 5'-CTTGTTCTCTGTACATGAAGGAGCTA-3' (forward primer), 5'-AAGACAAAATCCAAGCATTCAAAGTGTT-3' (reverse primer), and 5'-CTCTGGCAATGAAACCT-3' (MGB probe); for POP7, 5'-GCACCCACATCCTTCTTTCTCT-3' (forward primer), 5'-CCGCCAGGCCACTCAA-3' (reverse primer), and 5'-CCGGCCAGCCCAAGTA-3' (MGB probe). Gene dosage analysis results were confirmed by FISH, using the LSI EGFR SpectrumOrange/CEP 7 SpectrumGreen probe (Vysis; Abbott Laboratories;) according to the manufacture's protocol. FISH was performed on serial paraffin sections and in the same tissue areas as the gene dosage analysis. More than two or more increase of EGFR gene signals relative to CEP7 signals was considered as gene amplification.


   Results
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 Abstract
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 Materials and Methods
 Results
Discussion
 References
 
EGFR gene amplification is heterogeneously distributed in most individual tumors. Previous studies have shown that EGFR amplification is closely associated with EGFR mutations (8, 9). Thus, we selected 48 samples from patients with lung carcinomas and EGFR mutations. A total of three independent portions of each tumor were selected to represent morphologic differences. Gene amplification status was first screened using Taq Man–based gene dosage analysis. When a tumor portion showed a 2-fold or greater increase in copy number relative to normal tissue, gene amplification was confirmed by FISH. Using this procedure, we identified 11 tumors with EGFR amplification, summarized in Table 1 . The amplification signals were loosely clustered (Fig. 1 ), suggesting that the amplification occurred as homogenously staining regions. The incidence of gene amplification was consistent with those reported in the literature (8, 9, 20). Strikingly, EGFR amplification in 9 of the 11 tumors was distributed heterogeneously, whereas all three portions of the other two tumors showed equal levels of amplification throughout the tumor, suggesting homogeneous distribution. Regardless of the presence or absence of the amplification, EGFR mutation was detected in all of the individual portions from the 11 tumors.


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  		Table 1. Clinicopathological features of lung cancer with both EGFR mutation and amplification

 

Figure 1
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  		Figure 1. Representative morphologic features at three portions and corresponding FISH results (case ID 5 in Table 1). Portion 1, a noninvasive lesion, which frequently has bronchioloalveolar features. Papillary growth and solid glandular aggregates are characteristic in portions 2 and 3, respectively. EGFR gene amplification was seen in portions 2 and 3. All the portions have a confirmed 9-bp deletion in exon 19.

 
High-grade tumor areas with invasive growth harbor gene amplification. We next examined whether gene amplification was associated with particular morphologic features of tumors. As summarized in Table 1, EGFR amplification was correlated with high histologic grade and/or invasive growth. This association was statistically significant (Table 2 ; Fisher's exact test; two tailed, P < 0.01). As reported previously (21), adenocarcinoma with EGFR mutations frequently showed bronchioloalveolar features in the tumor periphery. In adenocarcinoma cases 3 to 7 and 9, the peripheral areas showing lepidic growth did not harbor the EGFR amplification (Fig. 1). Sample 11 was an adenosquamous cell carcinoma, and both adenocarcinoma and squamous cell carcinoma areas of the tumor harbored gene amplification.


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  		Table 2. Histological features and EGFR amplification

 
EGFR amplification was not always associated with metastatic clone. The metastatic lymph nodes corresponding to the five tumors with heterogeneous amplification were analyzed to determine if high-grade lesions within the tumor are potential sources of metastases (Table 3 ). A metastatic lymph node from an adenocarcinoma with homogeneous gene amplification (case ID 1) was also found to have a gene amplification equal to the primary tumors. For this metastatic carcinoma, two portions were microdissected and examined individually. The amplification was homogeneous even within the metastatic site of the tumor. In contrast, the EGFR amplification status of metastatic lymph nodes was diverse in the other four tumors showing heterogeneous distribution of the gene amplification. In case 4, gene amplification was detected only in a part of three independent lymph nodes examined, whereas the metastatic site showed a homogeneous distribution despite the heterogeneity of the primary tumor in case 5 (Fig. 2 ). Taken together, these results suggest that other factors contribute to the observed metastasis.


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  		Table 3. EGFR amplification in metastatic lymph nodes

 

Figure 2
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  		Figure 2. Representative results of EGFR amplification in mediastinal and hilar lymph nodes with metastasis (case ID 5). Two portions in individual lymph nodes were selected for analysis to represent morphologic differences. Only one of the four portions (hilar 2) harbors EGFR gene amplification.

 
EGFR gene amplification is very rare in precursor and in situ lesions for lung adenocarcinomas. Because we observed EGFR gene amplification primarily in high-grade tumor regions, we hypothesized that precursor lesions and in situ lung adenocarcinoma would not show gene amplification. We examined the gene amplification status in 17 samples of precursor lesions (AAH) and 21 of in situ lesions (bronchioalveolar carcinoma; BAC), 23 minimally invasive adenocarcinomas, and 46 invasive adenocarcinomas that recurred after surgery. In the schema of lung cancer progression, whereas EGFR was mutated from the precancerous stage, EGFR amplification was detected mostly in the invasive stage and after (Table 4 ). These findings are consistent with those obtained in the transsectional analysis and suggest that gene amplification occurs in the later stages of lung adenocarcinoma development. Similar to previous reports (8, 9), EGFR amplification was found exclusively in adenocarcinomas with EGFR mutation. The incidence of KRAS mutation was curiously on the decrease along with the progression schema from precancerous to minimally invasive carcinoma.


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  		Table 4. Comparison of EGFR mutation, amplification, and KRAS mutation by histological subtypes along with the putative progression schema

 

   Discussion
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References
 
Cancer develops as a result of many dysregulated signaling pathways, many of which are caused by genetic alterations as well as epigenetic changes. For impairment of one pathway, it is sufficient to involve a single gene. Lack of p16 alteration in small cell lung cancer is such example, because RB, upstream regulator of p16, is already inactivated in nearly all the cancer. In this context, simultaneous gene mutation and amplification is quite rare. A recent article by Abbott et al. (22) reported a rare, simultaneous gene alteration of platelet-derived growth factor β (PDGFB) in dermatofibrosarcoma protuberances (DFSP). DFSP is a low-grade sarcoma, characterized by continuous activation of the PDGFB as a consequence of a translocation of collagen type I {alpha} 1 and PDGFRB [t(17;22;q21;q13)]. On rare occasions, this sarcoma evokes fibrosarcomatous transformation, and gene amplifications of PDGFB in addition to the translocation were detected exclusively in the transformed lesion. These results suggest that gene amplification contributes to the high grade transformation of this tumor.

The EGFR locus can also have both mutation and amplification. As mentioned before, EGFR is amplified only in EGFR-mutated tumors, and the amplified allele is likely to be the mutated one. These findings suggest that mutation and amplification are closely associated with each other. We have reported that the EGFR mutation was involved specifically in the terminal respiratory unit type adenocarcinoma, characterized by expression of thyroid transcription factor 1 (TTF-1), a lineage marker of peripheral airway cells (23, 24). Recent identification of TTF-1 gene amplification in this subtype supports the hypothesis that terminal respiratory unit type adenocarcinoma is a distinct subset of lung adenocarcinoma (25). Furthermore, unsupervised hierarchical clustering based on expression profiles clearly show that this is a unique subset of adenocarcinoma (26), which was called "bronchioid" (27), "terminal sac/alveolar stages-linked" (28), and "alveolar" (29) in the different studies, in addition to terminal respiratory unit type adenocarcinoma. Characteristically, this tumor frequently shows high morphologic diversity within individual tumors, with invasion in the center of the nodule and in situ lepidic growth in the periphery. These features are frequently called a representation of the adenoma-carcinoma sequence seen in colon cancer, and lung adenocarcinoma is considered to be developmentally analogous to colon carcinoma. Indeed, allelic loss was shown to be associated with progression (30, 31), although none of the other genetic alterations were found in lung cancer. The present study revealed that gene amplification was heterogeneously distributed in sections of adenocarcinoma tumor tissues, and EGFR amplification was associated with a higher grade of individual tumors. EGFR can be mutated in precursor lesions of lung adenocarcinoma, but EGFR amplification is rather rare. Furthermore, EGFR mutation was uniformly detected in the nine tumors with heterogeneous EGFR amplification. Taking this together, we suggest that the mutation precedes the amplification and that EGFR gene amplification may occur during the progression to invasive cancer.

In addition to EGFR mutation, KRAS mutation also plays a crucial role in the molecular pathogenesis of lung adenocarcinoma and is acquired in early step of the carcinogenesis. As shown in Table 4, a precancerous lesion, AAH, also harbored a KRAS mutation. However, the frequencies of the EGFR and KRAS mutation showed quite different trends in putative schema of adenocarcinoma development. As reported in a previous study (18), high frequencies of KRAS mutations in AAH but not in in situ carcinomas and early invasive carcinomas. In contrast, the incidence of EGFR mutation was higher in in situ and invasive cancers. It may be possible that the present cohort does not represent clinical disease; however, similar frequencies of these mutations in the spectrum of tumors have been reported (32). Therefore, this suggests that either KRAS or EGFR mutations were associated with the development of AAH, but AAH with KRAS mutations seemed to lack the capability to progress to invasive cancer. However, it could be possible that AAH is a lesion that failed to progress to invasive cancer, independent of the acquired gene alterations. In other words, when a lesion cannot progress to invasive cancer, it may turn into an AAH lesion, regardless of the acquired mutation. The preferential amplification of EGFR in high-grade areas within the individual EGFR-mutated tumors observed in this study might provide a new clue for this query. AAH with EGFR mutations may progress to invasive cancer through additional alterations, including EGFR gene amplification, whereas large barriers may hinder the progression of KRAS-mutated AAH.

Although progression-associated gene amplification was suggested, the observed amplification does not seem to contribute to metastasis. In this study, not all metastatic lesions were derived from the gene-amplified area within the primary tumors that showed heterogeneous distribution of gene amplification. Even in the metastatic site, heterogeneity of amplification status was observed similar to the primary tumors. Thus, we suggested that selection of the metastatic clone may be defined by other factors (33, 34).

In summary, we examined the topographical distribution of EGFR amplification in individual tumors, using 48 lung adenocarcinomas with EGFR mutations. EGFR was amplified both heterogeneously and homogeneously in association with morphologic diversity of the tumors, suggesting that lung adenocarcinoma with EGFR mutations may acquire the additional gene amplification during the progression to invasive cancer.


   Acknowledgments
 
Grant support: Grant-in-Aid (C-19590379) from the Ministry of Education, Culture, Sports, Science, and Technology of Japan.

The costs of publication of this article were defrayed in part by the payment of page charges. This article must therefore be hereby marked advertisement in accordance with 18 U.S.C. Section 1734 solely to indicate this fact.

We thank Noriko Shibata and Yukiko Igawa for excellent technical assistance with the molecular genetic experiments, and Hiroji Ishida and the members of the Department of Pathology, Aichi Cancer Center, for assistance in preparing the paraffin sections.

Received 9/ 7/07. Revised 1/16/08. Accepted 1/29/08.


   References
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 Abstract
 Introduction
 Materials and Methods
 Results
 Discussion
 References
 

  1. Lynch TJ, Bell DW, Sordella R, et al. Activating mutations in the epidermal growth factor receptor underlying responsiveness of non-small-cell lung cancer to gefitinib. N Engl J Med 2004;350:2129–39.[Abstract/Free Full Text]
  2. Paez JG, Janne PA, Lee JC, et al. EGFR mutations in lung cancer: correlation with clinical response to gefitinib therapy. Science 2004;304:1497–500.[Abstract/Free Full Text]
  3. Rosell R, Taron M, Reguart N, Isla D, Moran T. Epidermal growth factor receptor activation: how exon 19 and 21 mutations changed our understanding of the pathway. Clin Cancer Res 2006;12:7222–31.[Abstract/Free Full Text]
  4. Cappuzzo F, Ligorio C, Janne PA, et al. Prospective study of gefitinib in epidermal growth factor receptor fluorescence in situ hybridization-positive/phospho-Akt-positive or never smoker patients with advanced non-small-cell lung cancer: the ONCOBELL trial. J Clin Oncol 2007;25:2248–55.[Abstract/Free Full Text]
  5. Hirsch FR, Varella-Garcia M, Bunn PA, Jr., et al. Molecular predictors of outcome with gefitinib in a phase III placebo-controlled study in advanced non-small-cell lung cancer. J Clin Oncol 2006;24:5034–42.[Abstract/Free Full Text]
  6. Hirsch FR, Varella-Garcia M, McCoy J, et al. Increased epidermal growth factor receptor gene copy number detected by fluorescence in situ hybridization associates with increased sensitivity to gefitinib in patients with bronchioloalveolar carcinoma subtypes: a Southwest Oncology Group Study. J Clin Oncol 2005;23:6838–45.[Abstract/Free Full Text]
  7. Tsao MS, Sakurada A, Cutz JC, et al. Erlotinib in lung cancer - molecular and clinical predictors of outcome. N Engl J Med 2005;353:133–44.[Abstract/Free Full Text]
  8. Takano T, Ohe Y, Sakamoto H, et al. Epidermal growth factor receptor gene mutations and increased copy numbers predict gefitinib sensitivity in patients with recurrent non-small-cell lung cancer. J Clin Oncol 2005;23:6829–37.[Abstract/Free Full Text]
  9. Cappuzzo F, Hirsch FR, Rossi E, et al. Epidermal growth factor receptor gene and protein and gefitinib sensitivity in non-small-cell lung cancer. J Natl Cancer Inst 2005;97:643–55.[Abstract/Free Full Text]
  10. Schmidt L, Duh FM, Chen F, et al. Germline and somatic mutations in the tyrosine kinase domain of the MET proto-oncogene in papillary renal carcinomas. Nat Genet 1997;16:68–73.[CrossRef][Medline]
  11. Zhuang Z, Park WS, Pack S, et al. Trisomy 7-harbouring non-random duplication of the mutant MET allele in hereditary papillary renal carcinomas. Nat Genet 1998;20:66–9.[CrossRef][Medline]
  12. Okabe T, Okamoto I, Tamura K, et al. Differential constitutive activation of the epidermal growth factor receptor in non-small cell lung cancer cells bearing EGFR gene mutation and amplification. Cancer Res 2007;67:2046–53.[Abstract/Free Full Text]
  13. Shigematsu H, Lin L, Takahashi T, et al. Clinical and biological features associated with epidermal growth factor receptor gene mutations in lung cancers. J Natl Cancer Inst 2005;97:339–46.[Abstract/Free Full Text]
  14. Pao W, Miller VA, Politi KA, et al. Acquired resistance of lung adenocarcinomas to gefitinib or erlotinib is associated with a second mutation in the EGFR kinase domain. PLoS Med 2005;2:e73.[CrossRef][Medline]
  15. Ma ES, Wong CL, Siu D, Chan WK. Amplification, mutation and loss of heterozygosity of the EGFR gene in metastatic lung cancer. Int J Cancer 2007;120:1828–31; author reply 32–3.[CrossRef][Medline]
  16. Kosaka T, Yatabe Y, Endoh H, Kuwano H, Takahashi T, Mitsudomi T. Mutations of the epidermal growth factor receptor gene in lung cancer: biological and clinical implications. Cancer Res 2004;64:8919–23.[Abstract/Free Full Text]
  17. Marchetti A, Buttitta F, Pellegrini S, et al. Bronchioloalveolar lung carcinomas: K-ras mutations are constant events in the mucinous subtype. J Pathol 1996;179:254–9.[CrossRef][Medline]
  18. Sakamoto H, Shimizu J, Horio Y, et al. Disproportionate representation of KRAS gene mutation in atypical adenomatous hyperplasia, but even distribution of EGFR gene mutation from preinvasive to invasive adenocarcinomas. J Pathol 2007;212:287–94.[CrossRef][Medline]
  19. Yatabe Y, Hida T, Horio Y, Kosaka T, Takahashi T, Mitsudomi T. A rapid, sensitive assay to detect EGFR mutation in small biopsy specimens from lung cancer. J Mol Diagn 2006;8:335–41.[Abstract/Free Full Text]
  20. Bell DW, Lynch TJ, Haserlat SM, et al. Epidermal growth factor receptor mutations and gene amplification in non-small-cell lung cancer: molecular analysis of the IDEAL/INTACT gefitinib trials. J Clin Oncol 2005;23:8081–92.[Abstract/Free Full Text]
  21. Marchetti A, Martella C, Felicioni L, et al. EGFR mutations in non-small-cell lung cancer: analysis of a large series of cases and development of a rapid and sensitive method for diagnostic screening with potential implications on pharmacologic treatment. J Clin Oncol 2005;23:857–65.[Abstract/Free Full Text]
  22. Abbott JJ, Erickson-Johnson M, Wang X, Nascimento AG, Oliveira AM. Gains of COL1A1-PDGFB genomic copies occur in fibrosarcomatous transformation of dermatofibrosarcoma protuberans. Mod Pathol 2006;19:1512–8.[Medline]
  23. Yatabe Y. Molecular classification of tumors with special reference to EGFR mutation in lung cancer. Cancer Chemother Pharmacol 2006;58 Suppl 1:17–23.[CrossRef]
  24. Yatabe Y, Mitsudomi T. Epidermal growth factor receptor mutations in lung cancers. Pathol Int 2007;57:233–44.[CrossRef][Medline]
  25. Tanaka H, Yanagisawa K, Shinjo K, et al. Lineage-specific dependency of lung adenocarcinomas on the lung development regulator TTF-1. Cancer Res 2007;67:6007–11.[Abstract/Free Full Text]
  26. Takeuchi T, Tomida S, Yatabe Y, et al. Expression profile-defined classification of lung adenocarcinoma shows close relationship with underlying major genetic changes and clinicopathologic behaviors. J Clin Oncol 2006;24:1679–88.[Abstract/Free Full Text]
  27. Hayes DN, Monti S, Parmigiani G, et al. Gene expression profiling reveals reproducible human lung adenocarcinoma subtypes in multiple independent patient cohorts. J Clin Oncol 2006;24:5079–90.[Abstract/Free Full Text]
  28. Borczuk AC, Gorenstein L, Walter KL, Assaad AA, Wang L, Powell CA. Non-small-cell lung cancer molecular signatures recapitulate lung developmental pathways. Am J Pathol 2003;163:1949–60.[Abstract/Free Full Text]
  29. Shibata T, Uryu S, Kokubu A, et al. Genetic classification of lung adenocarcinoma based on array-based comparative genomic hybridization analysis: its association with clinicopathologic features. Clin Cancer Res 2005;11:6177–85.[Abstract/Free Full Text]
  30. Aoyagi Y, Yokose T, Minami Y, et al. Accumulation of losses of heterozygosity and multistep carcinogenesis in pulmonary adenocarcinoma. Cancer Res 2001;61:7950–4.[Abstract/Free Full Text]
  31. Yatabe Y, Konishi H, Mitsudomi T, Nakamura S, Takahashi T. Topographical distributions of allelic loss in individual non-small- cell lung cancers. Am J Pathol 2000;157:985–93.[Abstract/Free Full Text]
  32. Yoshida Y, Shibata T, Kokubu A, et al. Mutations of the epidermal growth factor receptor gene in atypical adenomatous hyperplasia and bronchioloalveolar carcinoma of the lung. Lung Cancer 2005;50:1–8.[CrossRef][Medline]
  33. Kang Y, Siegel PM, Shu W, et al. A multigenic program mediating breast cancer metastasis to bone. Cancer Cell 2003;3:537–49.[CrossRef][Medline]
  34. Tomida S, Yanagisawa K, Koshikawa K, et al. Identification of a metastasis signature and the DLX4 homeobox protein as a regulator of metastasis by combined transcriptome approach. Oncogene 2007;26:4600–8.[CrossRef][Medline]



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