title: A fluorescence in situ hybridization (FISH) microfluidic platform for detection of HER2 amplification in cancer cells.
abstract: Over-expression/amplification of human epidermal growth factor receptors 2 (HER2) is a verified therapeutic biomarker for breast and gastric cancers. HER2 is also served as prognostic biomarker for gastric cancer because HER2 over-expression is associated with a 5-10% increase in cancer related death of gastric cancer. Cancer patients exhibiting HER2 over-expression can significantly improve their overall survival rates by taking the targeting drug Herceptin, which directly targets HER2. However, Herceptin has limited functions toward patients without HER2 over-expression and therefore it needs a highly specific and accurate detection method for diagnosis of HER2 over-expression. Currently, fluorescence in situ hybridization (FISH) technique is routinely employed to detect HER2 amplification. However, it is a labor-intensive, time-consuming hybridization process and is relatively costly. Furthermore, well-trained personnel are required to operate the delicate and complicate process. More importantly, it may take 1-2 days for well-trained personnel to perform a whole FISH assay. Given these limitations, we developed a new, integrated microfluidic FISH system capable of automating the entire FISH protocol which could be performed within a shorter period of time when compared to traditional methods. The microfluidic FISH chip consisted of a microfluidic control module for transportation of small amounts of fluids and a hybridization module to perform the hybridization of DNA probes and cells/tissue samples. With this approach, the new microfluidic chip was capable of performing the whole FISH assay within 20h. Four cell lines, two for non-HER2 amplification and two for HER2 amplification, and two clinical tissue samples, one for non-HER2 amplification and another for HER2 amplification, were used for verifications of the developed chip. Experimental data showed that there was no significant difference between the benchtop protocol and the chip-based protocol. Furthermore, the reagent consumption was greatly reduced (∼70% reduction). Especially, only 2-μl usage for FISH deoxyribonucleic acid (DNA) probe was used, which is five-fold reduction when compared with the traditional method. It is the first time that the entire FISH assay could be automated on a single chip by using tissue samples. The microfluidic system developed herein is therefore promising for rapid, automatic diagnosis of HER2-related diseases by detecting the HER2 gene with minimal consumption of samples and reagents and has a great potential for future pharmacogenetic diagnostics and therapy.
authors.affiliation: Department of Power Mechanical Engineering, National Tsing Hua University, Hsinchu 300, Taiwan.
authors.forename: Kai-Jie
authors.initials: KJ
authors.lastname: Kao
authors.affiliation: Department of Power Mechanical Engineering, National Tsing Hua University, Hsinchu 300, Taiwan.
authors.forename: Chien-Hsuan
authors.initials: CH
authors.lastname: Tai
authors.affiliation: Department of Power Mechanical Engineering, National Tsing Hua University, Hsinchu 300, Taiwan.
authors.forename: Wen-Hsin
authors.initials: WH
authors.lastname: Chang
authors.affiliation: Department of Surgery, Chang Gung Memorial Hospital at Linkou, Chang Gung University, Taoyuan 333, Taiwan.
authors.forename: Ta-Sen
authors.initials: TS
authors.lastname: Yeh
authors.affiliation: Department of Pathology, Chang Gung Memorial Hospital at Linkou, Chang Gung University, Taoyuan 333, Taiwan.
authors.forename: Tse-Ching
authors.initials: TC
authors.lastname: Chen
authors.affiliation: Department of Power Mechanical Engineering, National Tsing Hua University, Hsinchu 300, Taiwan; Institute of Biomedical Engineering, National Tsing Hua University, Hsinchu 300, Taiwan; Institute of NanoEngineering and Microsystems, National Tsing Hua University, Hsinchu 300, Taiwan. Electronic address: gwobin@pme.nthu.edu.tw.
authors.forename: Gwo-Bin
authors.initials: GB
authors.lastname: Lee
mesh_terms: D014408:Biomarkers, Tumor / Q000378:metabolism*; D045744:Cell Line, Tumor; D004867:Equipment Design; D019544:Equipment Failure Analysis; D020869:Gene Expression Profiling / Q000295:instrumentation*; D006801:Humans; D017404:In Situ Hybridization, Fluorescence / Q000295:instrumentation*; D056656:Lab-On-A-Chip Devices; D009374:Neoplasms, Experimental / Q000378:metabolism*; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000378:metabolism*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D015854:Up-Regulation
chemical_list: D014408:Biomarkers, Tumor; D018719:Erb-b2 Receptor Tyrosine Kinases; C508053:ERBB2 protein, human
keywords: Biomarker; Cancer; Fluorescence in situ hybridization (FISH); HER2; Herceptin; Microfluidics