Clinical relevance of miR-mediated HLA-G regulation and the associated immune cell infiltration in renal cell carcinoma

Abstract

In human tumors of distinct origin including renal cell carcinoma (RCC), the non-classical human leukocyte antigen G (HLA-G) is frequently expressed, thereby inhibiting the cytotoxic activity of T and natural killer (NK) cells. Recent studies demonstrated a strong post-transcriptional gene regulation of the HLA-G by miR-152, -148A, -148B and -133A. Standard methods were applied to characterize the expression and function of HLA-G, HLA-G-regulatory microRNAs (miRs) and the immune cell infiltration in 453 RCC lesions using a tissue microarray and five RCC cell lines linking these results to clinical parameters. Direct interactions with HLA-G regulatory miRs and the HLA-G 3' untranslated region (UTR) were detected and the affinities of these different miRs to the HLA-G 3'-UTR compared. qPCR analyses and immunohistochemical staining revealed an inverse expression of miR-148A and -133A with the HLA-G protein and. Stable miR overexpression caused a downregulation of HLA-G protein enhancing the NK and LAK cell-mediated cytotoxicity in CD107a activation assays revealing a HLA-G-dependent cytotoxic activity of immune effector cells. A significant higher frequency of CD3/CD8 T cell lymphocytes, but no differences in the activation markers CD69, CD25 or in the presence of CD56, FoxP3 and CD4 immune cells were detected in HLA-G compared to HLA-G RCC lesions. This could be associated with higher WHO grade, but not with a disease-specific survival. These data suggest a miR-mediated control of HLA-G expression in RCC, which is associated with a distinct pattern of immune cell infiltration.

Genetic variation at the 8q24.21 renal cancer susceptibility locus affects HIF binding to a MYC enhancer

“…The entire study has been approved by the local Ethical Committee at the University of Erlangen-Nürnberg and specimens were collected in accordance with the World Medical Association Declaration of Helsinki. Details on tissue microarray (TMA) composition and tumour characteristics have been published previously55. In short, archival FFPE tissues were reclassified according to the 2004 World Health Organization classification of renal tumours and the 2002 tumour node metastasis (TNM) classification by two uropathologists.…”

miR-146b antagomir–treated human Tregs acquire increased GVHD inhibitory potency

“…13,14 Multiple mechanisms have been implicated in tTreg development and suppressive function, including more recently miRNA's effects on posttranscriptional gene regulation. [15][16][17][18] The miR-146 family includes 2 main members, miR-146a and miR-146b, which are both highly expressed and play important roles in cell proliferation and function in diverse cell types, including T and B cells. Studies of breast cancer cells have shown a Foxp3-dependant increase in the expression of miR-146b and, to a lesser extent, miR-146a, 19 which results in reduced breast cancer cell proliferation and enhanced apoptosis via negative regulation of nuclear factor kB (NF-kB).…”

Adiponectin and Its Receptors Are Differentially Expressed in Human Tissues and Cell Lines of Distinct Origin

“…Total RNA was extracted from cell pellets employing TRIzol Reagent (Thermo Fisher Scientific), digested with DNase I (Promega, Mannheim, Germany) and applied for cDNA synthesis utilizing the RevertAidTM H Minus First Strand cDNA synthesis kit (Thermo Fisher Scientific) as recently described [23]. …”