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Nishino, H.

Publications and source records attributed to Nishino, H..

3 recordsLinked to original sources

A triple-negative matrix-producing breast carcinoma is arrested by tumor-targeting Salmonella typhimurium A1-R in a PDOX model

Background/AimMatrix-producing breast carcinoma (MPBC), is a rare, recalcitrant and highly aggressive. The present study aimed to determine the efficacy of tumor-targeting Salmonella typhimurium (S. typhimurium) A1-R on a triple-negative MPBC in a patient-derived orthotopic xenograft (PDOX) model. MethodsThe PDOX model was established in the left second mammary gland of a nude mouse by surgical orthotopic implantation (SOI) of the patient triple-negative MPBC PDOX models were randomized into two groups: G1, control group (n=6); G2, tumor-targeting S. typhimurium A1-R group (n=7, intravenous (i.v.) injection via tail vein, weekly, for two weeks). All mice were sacrificed on day 15. Tumor volume and body weight were measured one time per week. ResultsS. typhimurium A1-R arrested tumor growth compared to the control group (P = 0.016). ConclusionThe results of the present study suggest that S. typhimurium A1-R has future clinical potential in triple-negative MPBC patients.

cancer biology

Cancer-specific overmethylation of histone H3 lysines is necessary for methionine addiction and malignancy

Methionine addiction is a fundamental and general hallmark of cancer and is an area of current intense interest. Methionine addiction results from the overuse of methionine by cancer cells for excess transmethylation reactions. In order to identify excess transmethylation reactions in cancer and further understand the basis of methionine addiction, we compared the histone H3 lysine-methylation status and malignancy between methionine-addicted cancer cells and their methionine-independent revertants which have regained the ability to grow on low levels of methionine or independently of exogenous methionine. The levels of trimethylated histone H3 lysine marks were reduced in methionine-independent revertants compared to parental cancer cells in vitro. Tumorigenicity and experimental metastatic potential in nude mice were also highly reduced in the methionine-independent revertants compared to the parental cells. Our present results demonstrate that overmethylation of histone H3 lysines is linked with methionine addiction of cancer and to malignancy which suggests a possible causal relationship.

cancer biology

Coding of odour and space in the hemimetabolous insect Periplaneta americana

The general architecture of the olfactory system is highly conserved from insects to humans, but neuroanatomical and physiological differences can be observed across species. The American cockroach, inhabiting dark shelters with a rather stable olfactory landscape, is equipped with long antennae used for sampling the surrounding air-space for orientation and navigation. The antennaes exceptional length provides a wide spatial working range for odour detection; however, it is still largely unknown whether and how this is also used for mapping the structure of the olfactory environment. By selective labelling antennal lobe projection neurons with a calcium sensitive dye, we investigated the logic of olfactory coding in this hemimetabolous insect. We show that odour responses are stimulus-specific and concentration-dependent, and that structurally related odorants evoke physiologically similar responses. By using spatially confined stimuli, we show that proximal stimulations induce stronger and faster responses than distal ones. Spatially confined stimuli of the female pheromone periplanone-B activate sub-region of the male macroglomerulus. Thus, we report that the combinatorial logic of odour coding deduced from holometabolous insects applies also to this hemimetabolous species. Furthermore, a fast decrease in sensitivity along the antenna, not supported by a proportionate decrease in sensillar density, suggests a neural architecture that strongly emphasizes neuronal inputs from the proximal portion of the antenna. Summary statementBy selective labelling the cockroachs antennal lobe output neurons, we investigated the logic of olfactory coding in a hemimetabolous insect, showing that odour responses are stimulus-specific, concentration-dependent, and preserve information on the spatial structure of the stimulus.

neuroscience