Vese ischemia/reperfúziós károsodásának gátlása RNS interferencia segítségével = RNA interference (RNAi) to limit kidney ischemia/reperfusion injury.

Az RNS interferencia a génterápia új, ígéretes területe. Korábbi kísérleteink során elsőként alkalmaztuk ezt az új technológiát a vese ischemia-reperfúzós károsodásának gátlására (Hamar: PNAS, 2004, US.Apps - 20080227733). Az intenzív osztályon bekövetkezett haláleset kb. 30%-a a vese oxigénhiányos károsodásának következménye. Az oxigénhiányos állapotban elszenvedett szövetkárosodást kiterjedésében, súlyosságában meghaladhatja a véráramlás újbóli megindulását követő reperfúziós károsodás. A reperfúziós során keletkező oxigén szabadgyökök következtében súlyos oxidatív stressz okoz károsodást, és a sejtek programozott sejthalál (apoptózis) útján pusztulnak el. Ezért kísérleteink célja a vese reperfúziós károsodásának csökkentése. A FAS apoptózis receptor termelődését gátoló kezelésünk javította a veseműködést és a túlélést. A szabadgyök-termelő enzim kaszkád első elemét a NADPH-oxidáz (NOX-2,4) enzim termelődését gátló siRNS sejtkultúrában és egér-modellen javította a túlélést, a vese-működést. Kísérleteink során továbbá vizsgáljuk, az siRNS bejuttatásának leghatékonyabb módját, és az esetleges mellékhatásokat is. Eredményeinket két közleményben foglaltuk össze. A célszervbe-sejtbe történő bejuttatás hatékonyságának növelésében, sejt-specifikus célzott bevitel kifejlesztésében segítségünkre van Judy Liebermannal (Harvard Medical School, Boston, USA) akivel együttműködésben fejlesztettük ki az RNS interferencia alkalmazását egér máj és vese betegségek kezelésére. | RNA interference is a new, promising field of gene-therapy. We were the first, to apply this technique to inhibit reperfusion injury of the kidney (Hamar: PNAS, 2004, US.Apps - 20080227733). Renal oxygen depletion is a leading cause of death at the Intensive Care Units (ICU). Reperfusion injury following reconstitution of blood supply may substantially exceed the damage due to oxygen deficiency (ischemic injury). Oxygen radicals, produced during reperfusion induce a severe oxidative stress, and cells are lost through programmed cell death (apoptosis). Thus, our aim is to reduce reperfusion injury of the kidney. Inhibition of FAS apoptosis receptor improved renal function and survival. Inhibition of NADPH-oxidase (NOX-2,4) - the first enzyme of the oxidative radical producing enzyme cascade improved renal function, and cell survival in cell culture and mouse model. We summarized our data in 2 publications. Furthermore, we investigate the most effective way of targeting the siRNA in the right cell, and possible side-effects of siRNA in collaboration with Judy Liebermann (Harvard Medical School, Boston, USA), with whom we have developed application of RNA interference in mice for renal and liver diseases

Microvesicles secreted by macrophages shuttle invasion-potentiating microRNAs into breast cancer cells

<p>Abstract</p> <p>Background</p> <p>Tumor-associated macrophages (TAMs) are alternatively activated cells induced by interleukin-4 (IL-4)-releasing CD4⁺T cells. TAMs promote breast cancer invasion and metastasis; however, the mechanisms underlying these interactions between macrophages and tumor cells that lead to cancer metastasis remain elusive. Previous studies have found microRNAs (miRNAs) circulating in the peripheral blood and have identified microvesicles, or exosomes, as mediators of cell-cell communication. Therefore, one alternative mechanism for the promotion of breast cancer cell invasion by TAMs may be through macrophage-secreted exosomes, which would deliver invasion-potentiating miRNAs to breast cancer cells.</p> <p>Results</p> <p>We utilized a co-culture system with IL-4-activated macrophages and breast cancer cells to verify that miRNAs are transported from macrophages to breast cancer cells. The shuttling of fluorescently-labeled exogenous miRNAs from IL-4-activated macrophages to co-cultivated breast cancer cells without direct cell-cell contact was observed. miR-223, a miRNA specific for IL-4-activated macrophages, was detected within the exosomes released by macrophages and was significantly elevated in the co-cultivated SKBR3 and MDA-MB-231 cells. The invasiveness of the co-cultivated breast cancer cells decreased when the IL-4-activated macrophages were treated with a miR-223 antisense oligonucleotide (ASO) that would inhibit miR-223 expression. Furthermore, results from a functional assay revealed that miR-223 promoted the invasion of breast cancer cells via the Mef2c-β-catenin pathway.</p> <p>Conclusions</p> <p>We conclude that macrophages regulate the invasiveness of breast cancer cells through exosome-mediated delivery of oncogenic miRNAs. Our data provide insight into the mechanisms underlying the metastasis-promoting interactions between macrophages and breast cancer cells.</p

Hey factors at the crossroad of tumorigenesis and clinical therapeutic modulation of Hey for anticancer treatment

Hairy and Enhancer-of-split related with YRPW motif (Hey) transcription factors are important regulators of stem cell embryogenesis. Clinical relevance shows that they are also highly expressed in malignant carcinoma. Recent studies have highlighted functions for the Hey factors in tumor metastasis, the maintenance of cancer cell self-renewal, as well as proliferation and the promotion of tumor angiogenesis. Pathways that regulate Hey gene expression, such as Notch and TGFβ signaling, are frequently aberrant in numerous cancers. In addition, Hey factors control downstream targets via recruitment of histone deacetylases (HDAC). Targeting these signaling pathways or HDACs may reverse tumor progression and provide clinical benefit for cancer patients. Thus, some small molecular inhibitors or monoclonal antibodies of each of these signaling pathways have been studied in clinical trials. This review focuses on the involvement of Hey proteins in malignant carcinoma progression and provides valuable therapeutic information for anticancer treatment

Long Noncoding RNA Expression Signatures of Metastatic Nasopharyngeal Carcinoma and Their Prognostic Value

Long noncoding RNAs (lncRNAs) have recently been found to play important roles in various cancer types. The elucidation of genome-wide lncRNA expression patterns in metastatic nasopharyngeal carcinoma (NPC) could reveal novel mechanisms underlying NPC carcinogenesis and progression. In this study, lncRNA expression profiling was performed on metastatic and primary NPC tumors, and the differentially expressed lncRNAs between these samples were identified. A total of 33,045 lncRNA probes were generated for our microarray based on authoritative data sources, including RefSeq, UCSC Knowngenes, Ensembl, and related literature. Using these probes, 8,088 lncRNAs were found to be significantly differentially expressed (2-fold). To identify the prognostic value of these differentially expressed lncRNAs, four lncRNAs (LOC84740, ENST00000498296, AL359062, and ENST00000438550) were selected; their expression levels were measured in an independent panel of 106 primary NPC samples via QPCR. Among these lncRNAs, ENST00000438550 expression was demonstrated to be significantly correlated with NPC disease progression. A survival analysis showed that a high expression level of ENST00000438550 was an independent indicator of disease progression in NPC patients (). In summary, this study may provide novel diagnostic and prognostic biomarkers for NPC, as well as a novel understanding of the mechanism underlying NPC metastasis and potential targets for future treatment

Circular RNA hsa_circ_001783 regulates breast cancer progression via sponging miR-200c-3p

Increasing evidence suggests circular RNAs (circRNAs) exert critical functions in tumor progression via sponging miRNAs (microRNAs). However, the role of circRNAs in breast cancer remains unclear. Here we systematically analyzed the circular RNAs in breast cancer based on their characteristic in sponging disease-specific miRNAs and identified hsa_circ_001783 as a top ranked circRNA in our computation and verified its high expression in both breast cancer cells and cancer tissue. A higher level of hsa_circ_001783 was significantly correlated with heavier tumor burden and poorer prognosis of patients with breast cancer. Knockdown of this circRNA remarkably inhibited the proliferation and invasion of breast cancer cells. Importantly, hsa_circ_001783 promoted progression of breast cancer cells via sponging miR-200c-3p. Taken together, hsa_circ_001783 may serve as a novel prognostic and therapeutic target for breast cancer

PDGF-R inhibition induces glioblastoma cell differentiation via DUSP1/p38MAPK signalling

Glioblastoma (GBM) is the most common and fatal primary brain tumour in adults. Considering that resistance to current therapies leads to limited response in patients, new therapeutic options are urgently needed. In recent years, differentiation therapy has been proposed as an alternative for GBM treatment, with the aim of bringing cancer cells into a post-mitotic/differentiated state, ultimately limiting tumour growth. As an integral component of cancer development and regulation of differentiation processes, kinases are potential targets of differentiation therapies. The present study describes how the screening of a panel of kinase inhibitors (KIs) identified PDGF-Rα/β inhibitor CP-673451 as a potential differentiation agent in GBM. We show that targeting PDGF-Rα/β with CP-673451 in vitro triggers outgrowth of neurite-like processes in GBM cell lines and GBM stem cells (GSCs), suggesting differentiation into neural-like cells, while reducing proliferation and invasion in 3D hyaluronic acid hydrogels. In addition, we report that treatment with CP-673451 improves the anti-tumour effects of temozolomide in vivo using a subcutaneous xenograft mouse model. RNA sequencing and follow-up proteomic analysis revealed that upregulation of phosphatase DUSP1 and consecutive downregulation of phosphorylated-p38MAPK can underlie the pro-differentiation effect of CP-673451 on GBM cells. Overall, the present study identifies a potential novel therapeutic option that could benefit GBM patients in the future, through differentiation of residual GSCs post-surgery, with the aim to limit recurrence and improve quality of life

Small molecular inhibitors reverse cancer metastasis by blockading oncogenic PITPNM3

Most cancer‐related deaths are a result of metastasis. The development of small molecular inhibitors reversing cancer metastasis represents a promising therapeutic opportunity for cancer patients. This pan‐cancer analysis identifies oncogenic roles of membrane‐associated phosphatidylinositol transfer protein 3 (PITPNM3), which is crucial for cancer metastasis. Small molecules targeting PITPNM3 must be explored further. Here, PITPNM3‐selective small molecular inhibitors are reported. These compounds exhibit target‐specific inhibition of PITPNM3 signaling, thereby reducing metastasis of breast cancer cells. Besides, by using nanoparticle‐based delivery systems, these PITPNM3‐selective compounds loaded nanoparticles significantly repress metastasis of breast cancer in mouse xenograft models and organoid models. Notably, the results establish an important metastatic‐promoting role for PITPNM3 and offer PITPNM3 inhibition as a therapeutic strategy in metastatic breast cancer

MicroRNA100 Inhibits Self-Renewal of Breast Cancer Stem–like Cells and Breast Tumor Development

miRNAs are essential for self-renewal and differentiation of normal and malignant stem cells by regulating the expression of key stem cell regulatory genes. Here, we report evidence implicating the miR100 in self-renewal of cancer stem-like cells (CSC). We found that miR100 expression levels relate to the cellular differentiation state, with lowest expression in cells displaying stem cell markers. Utilizing a tetracycline-inducible lentivirus to elevate expression of miR100 in human cells, we found that increasing miR100 levels decreased the production of breast CSCs. This effect was correlated with an inhibition of cancer cell proliferation in vitro and in mouse tumor xenografts due to attenuated expression of the CSC regulatory genes SMARCA5, SMARCD1, and BMPR2. Furthermore, miR100 induction in breast CSCs immediately upon their orthotopic implantation or intracardiac injection completely blocked tumor growth and metastasis formation. Clinically, we observed a significant association between miR100 expression in breast cancer specimens and patient survival. Our results suggest that miR100 is required to direct CSC self-renewal and differentiation