Mami Ishikawa

Simultaneous Expression of Cancer Stem Cell-Like Properties and Cancer-Associated Fibroblast-Like Properties in a Primary Culture of Breast Cancer Cells

The importance of cancer-associated fibroblasts (CAFs) in cancer biology has been recently highlighted owing to their critical roles in cancer growth, progression, metastasis, and therapeutic resistance. We have previously established a primary culture of breast cancer cells, which showed epithelial-mesenchymal transition and cancer stem cell-like properties. In this study, we found that the primary culture also showed CAF-like properties. For example, hypoxia inducible factor 1α (HIF1A) and its downstream genes, nuclear factor-kappa B2 (NF-κB2) and BCL2/adenovirus E1B 19 kd-interacting protein 3 (BNIP3), and many enzymes involved in glycolysis, such as GAPDH, LDH, PGAM1, and PKM2, were highly overexpressed in the primary culture. Moreover, media conditioned with the primary culture cells enhanced the growth of breast cancer cells. Similar to previous CAF studies, this enhancement suggested to be occurred through fibroblast growth factor signaling. This MCKH primary culture cell, which showed simultaneous expression of tumorigenic and CAF properties, offers a unique experimental system for studying the biology of CAFs.

A high-throughput quantitative assay system for macrophage phagocytic activity

Innate immunity is at the frontline of defense against pathogens. Macrophages are a group of phagocytes that secrete cytokines to mediate the transmission of information on pathogen infectiousness to the acquired immune system. Our previous study established an assay for quantifying phagocytic activity in two human monocytic cell lines, U937 and THP-1. Overall, this assay system was quick, easy, and robust, except for the time-consuming quantification step using image analysis. Thus, in this study, we improved our previous assay system. For evaluating phagocytic activity, fluorescently labeled magnetic beads were phagocytosed and detected with a fluorescent-multi well plate reader. This system facilitates high-throughput screening of macrophage activating factors.

Effects of platinum and palladium nanocolloid on macrophage polarization in relevance to repigmentation of vitiligo

Elevated oxidative stress is accepted to be the initial event in vitiligo leading to the final pathological regulation of immune systems known as autoimmune reaction, which destroys melanin‐forming cells, melanocytes. Recently, we reported an efficient topical use of PAPLAL, nanocolloid of platinum and palladium, having intense catalase‐like activity to vitiligo patients. In addition, we found that PAPLAL has dual effects on the AhR and Nrf‐2 pathways in keratinocytes, and suggested its contribution to the recovery of immune state in vitiligo. The precise mechanism developing autoimmune reaction in vitiligo, however, remains to be clarified. It is important to clarify what kinds of cells play an essential role in the development of vitiligo.

Phagocytic Activation of Macrophages with Serum MAF Depends on Engulfment Efficiency and Not Migratory Activity

Background/Aim: Serum-derived macrophage activating factor (serum MAF) is known to increase the phagocytic activity of macrophages and potentially plays a role in activating cancer immunity. In order to reveal the contributing factors for phagocytic activation, the migratory activity and the efficiency of engulfment was analyzed. Materials and Methods: THP-1 macrophages were induced by 12-O-tetradecanoyl-13-acetate (TPA). The migratory activity and efficiency of engulfment were analyzed by time-lapse imaging and suspension assay, respectively. Results: While the distance of migration did not change before and after activation with serum MAF, the efficiency of beads internalisation was significantly increased. Conclusion: Phagocytic activation of serum-MAF-treated macrophages was caused by increasing the efficiency of engulfment. This study contributes to the knowledge about the activation of the immune system through phagocytic activation of macrophages.