Gradients of pH is formed in solid tumor tissues. We hypothesized that cancer cells in vivo might migrate toward intratumoral micro vessels along the pH gradient, thus promoting metastasis of tumor cells. To test this hypothesis, we devised the gap cover glass (GCG) that produces pH gradients in cultured MDA-MB-231 cells. In this study, we imaged heterogeneities of the extracellular pH under the GCG using a pH-sensitive fluorescent dye (BCECF). The pH gradient under the GCG depends on the cell density; -0.18 units/mm and -0.17 units/mm for the cell density at 3.5 x 10⁵ cells/ml and 16 x 10⁵ cells/ml, respectively, in L-15 culture medium. We demonstrated that the pH gradients were significantly reduced when hepes-DMEM medium was used instead of L-15. Currently, we are examining movement of the cell under these pH gradients.

An effective method is required to extract meaningful information from next-generation sequencer (NGS) because such extraction takes a considerable time. First, the proposed method detects mutations, which are mapped onto gene regions. These steps are repeated for another dataset. Then, the method extracts gene regions in which the number of mapped mutations is markedly different in the two datasets. The method was applied to datasets from multiple myeloma cell line cultured under normal and hypoxic conditions. Most of the extracted genes are tumor suppressors. This implies that mutations of tumor suppressors play a role in hypoxia tolerance, suggesting the usefulness of the proposed method.

Cell patterning is one of the fundamental techniques in biomedical and biological studies. We aim at patterning cells on an arbitrary shape by utilizing a magnetic scanning technology based on Magneto-Archimedes effect. Cells in paramagnetic solution behave as a diamagnetic particle and are subjected to a repulsive force from a magnet. Our method is able to pattern cells by neither labeling the cells magnetically nor contacting the cells directly. Fluorescent polystyrene beads with the similar physical properties to animal cells were suspended in paramagnetic solution. The magnet which was placed under the chamber containing the suspension was reciprocated using a motorized stage. As a result, the fluorescent beads in the area which the magnet passed were removed. The width of the area depended on the magnet diameter. This result suggests that our method is applicable for patterning cells on an arbitrary shape.

RNA analysis is necessary for early detection of cancer. Although qRT-PCR is used for RNA analysis, there are two problems for early detection of cancer. First, conventional device is large and heavy, and also requires a lot of high cost reagents for analysis. Here, we have developed a micro device for accurate RT-PCR only by nanoliter scale samples. The size is only a finger-tip scale, about 2 cm by 1 cm and 1 cm high, but can perform four sample analysis all at once. This device is composed by assembling each modules that have the function for performing RT-PCR, reactor module or heater module for instance, sterically. By the device structure, we succeed to reduce the energy for performing the reaction. By using the device system, we confirmed the accurate RNA expression analysis by various genes.

Our previous study indicated an altered correlation between a microRNA and its host gene in cancer. The host gene is highly likely to interact with target genes of the microRNA, and thus, a loop is formed in cancer. This study hypothesizes that the loop functions as positive feedback. Simulations using gene network in both cancerous and non-cancerous tissues were carried out to validate the hypothesis. A comparison between the simulation results and patients' data revealed that the simulations could reproduce the altered correlation, and the simulated gene expressions tended to be similar to the patients' data. This suggest that the loop functions as a positive feedback.

In this study, a hospital advising system was constructed for supporting such selection in this study. This system was programed by PHP using a relational database, and runs on the Web. This database stores the pertinent data to hospitals, clinical departments, symptoms, and diseases in the thirteen tables, which were connected by each data ID. Thus, this system is able to output candidate of suitable hospitals and clinical departments in response to clinical symptoms, hospital's location and preferred visiting date. However, the working area of the system was restricted to abdominal symptoms and to hospitals in Isehara city because this study is just pilot study. This system was verified by the comparison between the actual output and the predicted outcome based on expert knowledge in the input of 2178 kinds. And, good answers were obtained in a questionnaire relevant to the usability of the system.