EventsUNAMBG iGEM 2017 Team

Smelling Cancer

Metabolic changes due to diseases can be monitored also on volatile organic compound (VOC) levels in patient’s breath. These VOCs have different profile for each  disease. The motives of VOCs for each disease have been observed via different spectrometry methods, such as mass and gas spectrometry. The collected data have  been narrowed to select the very specific biomarkers for this project. The aim is to produce bacteria that have circuits and logic gates at DNA level which is going to  be able to either diagnose or detect the types of cancer by sensing specific VOCs in the exhaled breath of the patients mentioned before in literature.

For our sensors pMimA/MimR, pFor/Hxlr, pAlkM/AlkR, Pu/XylR and pChnB/ChnR promoter/transcription factors have been selected, which recognize acetone,  formaldehyde, octane, cyclohexanone and o-xylene presence, respectively. Transcription factor MimR binds to pMimA in the presence of acetone and isopropanol,  HxlR binds to pFor in the presence of formaldehyde and AlkR binds to pAlkM in the presence of octane which activates the transcription of the down stream genes.

For cyclohexanone sensor, pChnB (promoter of ChnB gene) has been selected since it binds transcription factor ChnR in the presence of cyclohexanone and for o-  xylene sensor Pu (promoter of XylR gene) has been selected since it binds to the transcription factor XylR in the presence of o-xylene, m-xylene, p-xylene and  toluene; so that transcription on this promoter is activated. Breath test which is a new field promising hope in medicine, offers a non-invasive and real-time method  that allows the monitoring of metabolic status. By making use of the data collected from different mass spectrometry samples collected from cancer patients,  electronic noses have been developed to sense the specific VOCs for each cancer. On the other hand, regarding the application process, every hospital will not be  able to afford electronic noses. In accordance with our works, producing new kit that can be routinely and easily used to diagnose cancer is one of our future goals.

Related publications:

1Peng, G., M. Hakim, Y. Y. Broza, S. Billan, R. Abdah-Bortnyak, A. Kuten, U. Tisch, and H. Haick. “Detection of Lung, Breast, Colorectal, and Prostate Cancers from  Exhaled Breath Using a Single Array of Nanosensors.” British Journal of Cancer 103.4 (2010): 542-51. Web.

2Wang, Changsong, Bo Sun, Lei Guo, Xiaoyang Wang, Chaofu Ke, Shanshan Liu, Wei Zhao, Suqi Luo, Zhigang Guo, Yang Zhang, Guowang Xu, and Enyou Li. “Volatile  Organic Metabolites Identify Patients with Breast Cancer, Cyclomastopathy, and Mammary Gland Fibroma.” Sci. Rep. Scientific Reports 4 (2014): n. pag. Web.

3Lavra, Luca, Alexandro Catini, Alessandra Ulivieri, Rosamaria Capuano, Leila Baghernajad Salehi, Salvatore Sciacchitano, Armando Bartolazzi, Sara Nardis, Roberto  Paolesse, Eugenio Martinelli, and Corrado Di Natale. “Investigation of VOCs Associated with Different Characteristics of Breast Cancer Cells.” Sci. Rep. Scientific  Reports 5 (2015): 13246. Web.

4Fuchs, P., Loeseken, C., Schubert, J., & Miekisch, W. (2010). Breath gas aldehydes as biomarkers of lung cancer. International Journal Of Cancer, 126(11), 2663-  2670. doi:10.1002/ijc.24970

5Wu W, Zhang L, Yao L, Tan X, Liu X, Lu X. Genetically assembled fluorescent biosensor for in situ detection of bio-synthesized alkanes. Scientific Reports[serial

online]. June 3, 2015;5Available from: Scopus®, Ipswich, MA. Accessed September 26, 2017.

6Furuya, T., Nakao, T., & Kino, K. (2015). Catalytic function of the mycobacterial binuclear iron monooxygenase in acetone metabolism. FEMS Microbiology Letters,  362(19), doi:10.1093/femsle/fnv136