Downstream interferon signaling through the type I interferon (IFN) receptor, IFNAR, is crucial for the proper production of type I IFNs in mounting anti-tumor immune responses. Our study investigates the role of type I IFN signaling in the glioblastoma (GBM) tumor microenvironment by leveraging single-cell RNA sequencing to analyze tumor-infiltrating lymphocytes. We investigate how type I IFN signaling within the myeloid compartment contributes to the crosstalk with T cells in the tumor microenvironment. Through the use of the Gl261 murine GBM model, we find that the lack of proper type I IFN response results in enhanced PD-L1 interactions among myeloid cells, thereby affecting T cell functionality. Additionally, we also characterize how anti-PD1 treatment induces transcriptional changes in tumor-associated monocytes and macrophages by analyzing intercellular communication networks and propose how immune checkpoint blockade therapy could possibly relieve some of the immunosuppression derived from the lack of proper type I IFN production.
© 2024 The Author(s).

The role of pyruvate kinase M2 isoform (PKM2) in tumor progression has been controversial. Previous studies showed that PKM2 promoted tumor growth in xenograft models; however, depletion of PKM2 in the Brca1-loss-driven mammary tumor mouse model accelerates tumor formation. Because oncogenic kinases are frequently activated in tumors and PKM2 phosphorylation promotes tumor growth, we hypothesized that phosphorylation of PKM2 by activated kinases in tumor cells confers PKM2 oncogenic function, whereas nonphosphorylated PKM2 is nononcogenic. Indeed, PKM2 was phosphorylated at tyrosine 105 (Y105) and formed oncogenic dimers in MDA-MB-231 breast cancer cells, whereas PKM2 was largely unphosphorylated and formed nontumorigenic tetramers in nontransformed MCF10A cells. PKM2 knockdown did not affect MCF10A cell growth but significantly decreased proliferation of MDA-MB-231 breast cancer cells with tyrosine kinase activation. Multiple kinases that are frequently activated in different cancer types were identified to phosphorylate PKM2-Y105 in our tyrosine kinase screening. Introduction of the PKM2-Y105D phosphomimetic mutant into MCF10A cells induced colony formation and the CD44hi/CD24neg cancer stem-like cell population by increasing Yes-associated protein (YAP) nuclear localization. ErbB2, a strong inducer of PKM2-Y105 phosphorylation, boosted nuclear localization of YAP and enhanced the cancer stem-like cell population. Treatment with the ErbB2 kinase inhibitor lapatinib decreased PKM2-Y105 phosphorylation and cancer stem-like cells, impeding PKM2 tumor-promoting function. Taken together, phosphorylation of PKM2-Y105 by activated kinases exerts oncogenic functions in part via activation of YAP downstream signaling to increase cancer stem-like cell properties.Significance: These findings reveal PKM2 promotes tumorigenesis by inducing cancer stem-like cell properties and clarify the paradox of PKM2's dichotomous functions in tumor progression. Cancer Res; 78(9); 2248-61. ©2018 AACR.
©2018 American Association for Cancer Research.

Human amniotic epithelial cells (hAECs) which are isolated from the amniotic membrane have stem cell-like properties and immunomodulatory effects. Several protocols have been proposed for isolation of hAECs, nevertheless, there is no report concerning isolation of highly viable hAECs, with desirable yield, and without significant purity reduction. In the current study, a detailed protocol with some modification of previous ones is presented in which the amendments led to isolation of hAECs with high purity, yield and viability. Moreover, isolated hAECs were subjected to immuno-phenotyping and their physiological status was assessed using a proliferation assay.
The average yield of obtained hAECs using the new modified method was 190 × 106 cells with a mean viability of 87%, with less than 1% contamination with mesenchymal stem cells (MSCs). The isolated cells were > 95% positive for the epithelial cell markers. The lowest initial plating efficiency of the cells was 80%. Freshly isolated hAECs had the ability to proliferate for 5-6 passages in a standard culture medium.

Vascular smooth muscle cells (VSMCs) switch to macrophage-like cells after cholesterol loading, and this change may play an important role in the progression of atherosclerosis. C1q/TNF-related protein 9 (CTRP9) is a recently discovered adipokine that has been shown to have beneficial effects on glucose metabolism and vascular function, particularly in regard to cardiovascular disease. The question of whether CTRP9 can protect VSMCs from cholesterol damage has not been addressed. In this study, the impact of CTRP9 on cholesterol-damaged VSMCs was observed. Our data show that in cholesterol-treated VSMCs, CTRP9 significantly reversed the cholesterol-induced increases in pro-inflammatory factor secretion, monocyte adhesion, cholesterol uptake and expression of the macrophage marker CD68. Meanwhile, CTRP9 prevented the cholesterol-induced activation of the TLR4-MyD88-p65 pathway and upregulated the expression of proteins important for cholesterol efflux. Mechanistically, as siRNA-induced selective gene ablation of AMPKα1 abolished these effects of CTRP9, we concluded that CTRP9 achieves these protective effects in VSMCs through the AMP-dependent kinase (AMPK) pathway.
© 2017 The Authors. Journal of Cellular and Molecular Medicine published by John Wiley & Sons Ltd and Foundation for Cellular and Molecular Medicine.

To establish a novel protocol for differentiation of retinal pigment epithelium (RPE) with high purity from mouse induced pluripotent stem cells (iPSC).
Retinal progenitor cells were differentiated from mouse iPSC, and RPE differentiation was then enhanced by activation of the Wnt signaling pathway, inhibition of the fibroblast growth factor signaling pathway, and inhibition of the Rho-associated, coiled-coil containing protein kinase signaling pathway. Expanded pigmented cells were purified by plate adhesion after Accutase® treatment. Enriched cells were cultured until they developed a cobblestone appearance with cuboidal shape. The characteristics of iPS-RPE were confirmed by gene expression, immunocytochemistry, and electron microscopy. Functions and immunologic features of the iPS-RPE were also evaluated.
We obtained iPS-RPE at high purity (approximately 98%). The iPS-RPE showed apical-basal polarity and cellular structure characteristic of RPE. Expression levels of several RPE markers were lower than those of freshly isolated mouse RPE but comparable to those of primary cultured RPE. The iPS-RPE could form tight junctions, phagocytose photoreceptor outer segments, express immune antigens, and suppress lymphocyte proliferation.
We successfully developed a differentiation/purification protocol to obtain mouse iPS-RPE. The mouse iPS-RPE can serve as an attractive tool for functional and morphological studies of RPE.