Detection of Gene Dosage in Circulating Free Plasma DNA as Biomarker for Lung Cancer


The increase in the number of gene copies at specific loci is a genetic alteration frequently associated with over expression of the related protein in cancer cells. Genes whose dose is consistently augmented in cancer include those involved in cell cycle control, proliferation, apoptosis, and angiogenesis among others. In this study, gene dose of onc ogenes MYCL1, MYCN, MYC, EGFR, ERBB2 and AKT2 in DNA obtained from lung tissue and blood plasma, of patients with primary lung cancer was evaluated with respect to normal lung tissue and plasma DNA of healthy individ uals, to determine the capacity of these genes to discriminate normal and neoplastic phenotypes. The number of copies of each gene was determined using real-time (2-△△CT). The AKT2 oncogene was found to be amplified frequently in plasma DNA from patients (74% of cases). This marker showed a noticeable ability to discriminate normal and neo-plastic phenotypes, with a 76 to 89% probability of correctly recognize a plasma sample provided by a lung cancer patient or a healthy individual. For this reason, this detection could be a very useful tool to supplement the existing diagnostic methods in pulmonary cancer.

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A. Mayerly Alvarez, S. Janneth Perdomo Lara, D. M. Palacios, E. Fabián Carrillo, L. Gerardo García Herreros, F. Camacho Durán, P. Ojeda León and F. A. Aristizábal, "Detection of Gene Dosage in Circulating Free Plasma DNA as Biomarker for Lung Cancer," Journal of Cancer Therapy, Vol. 3 No. 4A, 2012, pp. 343-351. doi: 10.4236/jct.2012.324045.

Conflicts of Interest

The authors declare no conflicts of interest.


[1] Applied Biosystems, “Guide to Performing Relative Quantitation of Gene Expression Using Real-Time Quantitative PCR,” 2004, pp. 1-70.
[2] J. Bean, C. Brennan, J. Y. Shih, G. Riely, A. Viale, L. Wang, D. Chitale, N. Motoi, J. Szoke, S. Broderick., et al., “MET Amplification Occurs with or without T790M Mutations in EGFR Mutant Lung Tumors with Acquired Resistance to Gefitinib or Erlotinib,” Proceedings of the National Academy of Sciences, Vol. 104, No. 52, 2007, pp. 20932-20937.
[3] O. Canoz, M. Ozkan, V. Arsav, O. Er, H. S. Coskun, S. Soyuer and M. Altinbas, “The Role of c-erbB-2 Expression on the Survival of Patients with Small Cell Lung Cancer,” Lung, Vol. 184, No. 5, 2006, pp. 267-272. doi:10.1007/s00408-005-2591-y
[4] J. Q. Cheng, A. K. Godwin, A. Bellacosa, T. Taguchi, T. F. Franke, T. C. Hamilton, P. N. Tsichlis and J. R. Testa, “AKT2, a Putative Oncogene Encoding a Member of a Subfamily of Protein-Serine/Threonine Kinases, Is Amplified in Human Ovarian Carcinomas,” Proceedings of the National Academy of Sciences, Vol. 89, No. 19, 1992, pp. 9267-9271. doi:10.1073/pnas.89.19.9267
[5] J. Q. Cheng, B. Ruggeri, W. M. Klein, G. Sonoda, D. A. Altomare, D. K. Watson and J. R. Testa, “Amplification of AKT2 in Human Pancreatic Cells and Inhibition of AKT2 Expression and Tumorigenicity by Antisense RNA,” Proceedings of the National Academy of Sciences, Vol. 93, No. 8, 1996, pp. 3636-3641. doi:10.1073/pnas.93.8.3636
[6] J. A. Crowell and V. E. Steele, “AKT and the Phosphatidylinositol 3-Kinase/AKT Pathway: Important Molecular Targets for Lung Cancer Prevention and Treatment,” Journal of The National Cancer Institute, Vol. 95, No. 4, 2003, pp. 252-253. doi:10.1093/jnci/95.4.252
[7] J. Ferlay, H. R. Shin, F. Bray, D. Forman, C. Mathers and D. M. Parkin, “Estimates of Worldwide Burden of Cancer in 2008: GLOBOCAN 2008,” International Journal of Cancer, Vol. 127, No. 12, 2010, pp. 2893-2917. doi:10.1002/ijc.25516
[8] M. E. Garber, O. G. Troyanskaya, K. Schluens, S. Petersen, Z. Thaesler, M. Pacyna-Gengelbach, M. van de Rijn, G. D. Rosen, C. M. Perou, R. I. Whyte, et al., “Diversity of Gene Expression in Adenocarcinoma of the Lung,” Proceedings of the National Academy of Sciences, Vol. 98, No. 24, 2001, pp. 13784-13789. doi:10.1073/pnas.241500798
[9] W. C. Gustafson and W. A. Weiss, “Myc Proteins as Therapeutic Targets,” Oncogene, Vol. 29, No. 9, 2010, pp. 1249-1259. doi:10.1038/onc.2009.512
[10] R. Herbst, J. Heymach and S. Lippman, “Molecular Origins of Lung Cancer,” New England Journal of Medicine, Vol. 359, 2008, pp. 1367-1380. doi:10.1056/NEJMra0802714
[11] F. R. Hirsch, M. Varella-Garcia and F. Cappuzzo, “Predictive Value of EGFR and HER2 Overexpression in Advanced Non-Small-Cell Lung Cancer,” Oncogene, Vol. 28, Suppl. 1, 2009, pp. S32-S37. doi:10.1038/onc.2009.199
[12] C. Huang, L. Yang, Z. Li, J. Yang, J. Zhao, X. Dehui, L. Liu, Q. Wang and T. Song, “Detection of CCND1 Amplification Using Laser Capture Microdissection Coupled with Real-Time Polymerase Chain Reaction in Human Esopha-Geal Squamous Cell Carcinoma,” Cancer Genetics and Cytogenetics, Vol. 175, No. 1, 2007, pp. 19-25. doi:10.1016/j.cancergencyto.2007.01.003
[13] X. Lin, A. S. Bohle, P. Dohrmann, I. Leuschner, A. Schulz, B. Kremer and F. Fandrich, “Overexpression of Phosphatidylinositol 3-Kinase in Human Lung Cancer,” Langenbeck’s Archives of Surgery, Vol. 386, No. 4, 2001, pp. 293-301. doi:10.1007/s004230100203
[14] K. Livakand T. D. Schmittgen, “Analisys of Relative Gene Expression Data Using Real-Time Quantitative PCR and the 2(-Delta Delta C(T)) Method,” Methods, Vol. 25, No. 4, 2001, pp. 402-408. doi:10.1006/meth.2001.1262
[15] P. P. Massion, W.-L. Kuo, D. Stokoe, et al., “Genomic Copy Number Analysis of Non-Small Cell Lung Cancer Using Array Comparative Genomic Hybridization: Implications of the Phosphatidylinositol 3-Kinase Pathway,” Cancer Research, Vol. 62, No. 13, 2002, pp. 3636-3640.
[16] L. A. G. Ries, D. Melbert, M. Krapcho, et al., “SEER Cancer Statistics Review, 1975-2005,” National Cancer Institute, Bethesda, 2008.
[17] P. G. Rychahou, J. Kang, P. Gulhati, H. Q. Doan, L. A. Chen, S. Y. Xiao, D. H. Chung and B. M. Evers, “Akt2 Overexpression Plays a Critical Role in the Establishment of Colorectal Cancer Metastasis,” Proceedings of the National Academy of Sciences, Vol. 105, No. 51, 2008, pp. 20315-30320. doi:10.1073/pnas.0810715105
[18] H. Schwarzenbach, D. Hoon and K. Pantel, “Cell-Free Nucleic Acids as Biomarkers in Cancer Patients,” Nature Reviews Cancer, Vol. 11, 2011, pp. 426-437. doi:10.1038/nrc3066
[19] G. Sozzi, D. Conte, M. Leon, R. Ciricione, L. Roz, C. Ratcliffe, E. Roz, N. Cirenei, M. Bellomi, G. Pelosi, et al., “Quantification of Free Circulating DNA as a Diagnostic Marker in Lung Cancer,” Journal of Clinical Oncology, Vol. 21, No. 21, 2003, pp. 3902-3908. doi:10.1200/JCO.2003.02.006
[20] N. Umetani, J. Kim, S. Hiramatsu, H. A. Reber, O. J. Hines, A. J. Bilchik and D. S. Hoon, “Increased Integrity of Free Circulating DNA in Sera of Patients with Colorectal or Periampullary Cancer: Direct Quantitative PCR for ALU Repeats,” Clinical Chemistry, Vol. 52, No. 6, 2006, pp. 1062-1069. doi:10.1373/clinchem.2006.068577
[21] K. Wang, H. Yamamoto, J. R. Chin, Z. Werb and T. H. Vu, “Epidermal Growth Factor Receptor-Deficient Mice Have Delayed Primary Endochondral Ossification Because of Defective Osteoclast Recruitment,” Journal of Biological Chemistry, Vol. 279, No. 51, 2004, pp. 53848-53856.
[22] J. Wang, L. J. Miao, Y. M. Wu, Y. J. Wu and X. C. Wang, “Expression of AKT2, Cyclin d1 and MMP-9 and Their Correlation to Clinicopathologic Features of Non-Small Cell Lung Cancer,” Cancer, Vol. 25, No. 1, 2006, pp. 69-72.
[23] Q. G. Wu, T. T. Cao, Z. Cheng and J. Wang, “Effects of Akt2-siRNA on Chemotherapeutic Sensitivity and Drug Resistance in Human Lung Cancer Cells,” National Medical Journal of China, Vol. 91, No. 30, 2011, pp. 2139-2142.

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