Functional differentiation and scalable production of renal proximal tubular epithelial cells from human pluripotent stem cells in a dynamic culture system

ObjectiveTo provide a standardized protocol for large‐scale production of proximal tubular epithelial cells (PTEC) generated from human pluripotent stem cells (hPSC).MethodsThe hPSC were expanded and differentiated into PTEC on matrix‐coated alginate beads in an automated levitating fluidic platform bioLevitator. Differentiation efficacy was evaluated by immunofluorescence staining and flow cytometry, ultrastructure visualized by electron microscopy. Active reabsorption by PTEC was investigated by glucose, albumin, organic anions and cations uptake assays. Finally, the response to cisplatin‐treatment was assessed to check the potential use of PTEC to model drug‐induced nephrotoxicity.ResultshPSC expansion and PTEC differentiation could be performed directly on matrix‐coated alginate beads in suspension bioreactors. Renal precursors arose 4 days post hPSC differentiation and PTEC after 8 days with 80% efficiency, with a 10‐fold expansion from hPSC in 24 days. PTEC on beads, exhibited microvilli and clear apico‐basal localization of markers. Functionality of PTECs was confirmed by uptake of glucose, albumin, organic anions and cations and expression of KIM‐1 after Cisplatin treatment.ConclusionWe demonstrate the efficient expansion of hPSC, controlled differentiation to renal progenitors and further specification to polarized tubular epithelial cells. This is the first report employing biolevitation and matrix‐coated beads in a completely defined medium for the scalable and potentially automatable production of functional human PTEC.     

Large‐scale generation of megakaryocytes from human embryonic stem cells using transgene‐free and stepwise defined suspension culture conditions

ObjectivesEx vivo engineered production of megakaryocytes (MKs) and platelets (PLTs) from human pluripotent stem cells is an alternative approach to solve shortage of donor‐donated PLTs in clinics and to provide induced PLTs for transfusion. However, low production yields are observed and the generation of clinically applicable MKs and PLTs from human pluripotent stem cells without genetic modifications still needs to be improved.Materials and MethodsWe defined an optimal, stepwise and completely xeno‐free culture protocol for the generation of MKs from human embryonic stem cells (hESCs). To generate MKs from hESCs on a large scale, we improved the monolayer induction manner to define three‐dimensional (3D) and sphere‐like differentiation systems for MKs by using a special polystyrene CellSTACK culture chamber.ResultsThe 3D manufacturing system could efficiently generate large numbers of MKs from hESCs within 16‐18 days of continuous culturing. Each CellSTACK culture chamber could collect on an average 3.4 × 10⁸ CD41⁺ MKs after a three‐stage orderly induction process. MKs obtained from hESCs via 3D induction showed significant secretion of IL‐8, thrombospondin‐1 and MMP9. The induced cells derived from hESCs in our culture system were shown to have the characteristics of MKs as well as the function to form proPLTs and release PLTs. Furthermore, we generated clinically applicable MKs from clinical‐grade hESC lines and confirmed the biosafety of these cells.ConclusionsWe developed a simple, stepwise, 3D and completely xeno‐free/feeder‐free/transgene‐free induction system for the generation of MKs from hESCs. hESC‐derived MKs were shown to have typical MK characteristics and PLT formation ability. This study further enhances the clinical applications of MKs or PLTs derived from pluripotent stem cells.     

Development of a 3D‐printed single‐use separation chamber for use in mRNA‐based vaccine production with magnetic microparticles

Laboratory protocols using magnetic beads have gained importance in the purification of mRNA for vaccines. Here, the produced mRNA hybridizes specifically to oligo(dT)‐functionalized magnetic beads after cell lysis. The mRNA‐loaded magnetic beads can be selectively separated using a magnet. Subsequently, impurities are removed by washing steps and the mRNA is eluted. Magnetic separation is utilized in each step, using different buffers such as the lysis/binding buffer. To reduce the time required for purification of larger amounts of mRNA vaccine for clinical trials, high‐gradient magnetic separation (HGMS) is suitable. Thereby, magnetic beads are selectively retained in a flow‐through separation chamber. To meet the requirements of biopharmaceutical production, a disposable HGMS separation chamber with a certified material (United States Pharmacopeia Class VI) was developed which can be manufactured using 3D printing. Due to the special design, the filter matrix itself is not in contact with the product. The separation chamber was tested with suspensions of oligo(dT)‐functionalized Dynabeads MyOne loaded with synthetic mRNA. At a concentration of c_B = 1.6–2.1 g·L^–1 in lysis/binding buffer, these 1 μm magnetic particles are retained to more than 99.39% at volumetric flows of up to 150 mL·min^–1 with the developed SU‐HGMS separation chamber. When using the separation chamber with volumetric flow rates below 50 mL·min^–1, the retained particle mass is even more than 99.99%.     

Deletion of SA β‐Gal+ cells using senolytics improves muscle regeneration in old mice

Systemic deletion of senescent cells leads to robust improvements in cognitive, cardiovascular, and whole‐body metabolism, but their role in tissue reparative processes is incompletely understood. We hypothesized that senolytic drugs would enhance regeneration in aged skeletal muscle. Young (3 months) and old (20 months) male C57Bl/6J mice were administered the senolytics dasatinib (5 mg/kg) and quercetin (50 mg/kg) or vehicle bi‐weekly for 4 months. Tibialis anterior (TA) was then injected with 1.2% BaCl₂ or PBS 7‐ or 28 days prior to euthanization. Senescence‐associated β‐Galactosidase positive (SA β‐Gal+) cell abundance was low in muscle from both young and old mice and increased similarly 7 days following injury in both age groups, with no effect of D+Q. Most SA β‐Gal+ cells were also CD11b+ in young and old mice 7‐ and 14 days following injury, suggesting they are infiltrating immune cells. By 14 days, SA β‐Gal+/CD11b+ cells from old mice expressed senescence genes, whereas those from young mice expressed higher levels of genes characteristic of anti‐inflammatory macrophages. SA β‐Gal+ cells remained elevated in old compared to young mice 28 days following injury, which were reduced by D+Q only in the old mice. In D+Q‐treated old mice, muscle regenerated following injury to a greater extent compared to vehicle‐treated old mice, having larger fiber cross‐sectional area after 28 days. Conversely, D+Q blunted regeneration in young mice. In vitro experiments suggested D+Q directly improve myogenic progenitor cell proliferation. Enhanced physical function and improved muscle regeneration demonstrate that senolytics have beneficial effects only in old mice.     

Telmisartan anti‐cancer activities mechanism through targeting N‐cadherin by mimicking ADH‐1 function

This study aimed to investigate if Telmisartan as a novel N‐cadherin antagonist, can overcome cell migration of cancer cells. We investigated the mechanism and influence of Docetaxel and Telmisartan (as an analogous to ADH‐1, which is a well‐known N‐cadherin antagonist) on cancer cells. The effect of ADH‐1 and Telmisartan on cell attachment in PC3, DU145, MDA‐MB‐468 cell lines using recombinant human N‐cadherin was studied. Cell viability assay was performed to examine the anti‐proliferative effects of Telmisartan, ADH‐1 and Docetaxel. Migration was examined via wound healing assay, and apoptosis was determined by flow cytometry. The expression of AKT‐1 as a downstream gene of N‐cadherin signalling pathway was assayed by real‐time PCR. Treatment of PC3, MDA‐MB‐468 and DU145 cells with Telmisartan (0.1 µM) and ADH‐1 (40 µM) resulted in 50%, 58% and approximately 20% reduction in cell attachment to N‐cadherin coated plate respectively. It shows reduction of cell attachment in PC3 and MDA‐MB‐468 cell lines appeared to be more sensitive than that of DU145 cells to the Telmisartan and ADH‐1 treatments. Telmisartan (0.1 µM) and Docetaxel (0.01 nM) significantly reduced cell migration in PC3 and MDA‐MB‐468 cell lines compared with the control group. Using Real‐time PCR, we found that Telmisartan, Docetaxel and ADH‐1 had significant influence on the AKT‐1 mRNA level. The results of the current study for the first time suggest that, Telmisartan, exerts anti‐proliferation and anti‐migration effects by targeting antagonistically N‐cadherin. Also, these data suggest that Telmisartan as a less expensive alternative to ADH‐1 could potentiate Docetaxel anticancer effects.     

METTL3‐mediated maturation of miR‐589‐5p promotes the malignant development of liver cancer

MiR‐589‐5p could promote liver cancer, but the specific mechanisms are largely unknown. This study examined the role and mechanisms of miR‐589‐5p in liver cancer. The expressions of miR‐589‐5p, METTL3 and m6A in liver cancers were determined by RT‐qPCR. The relationship between miR‐589‐5p and METTL3‐mediated m6A methylation was examined by m6A RNA immunoprecipitation. After transfection, the viability, migration, invasion and expressions of METTL3 and miR‐589‐5p in liver cancer cells were detected by CCK‐8, wound‐healing, transwell and RT‐qPCR. After the xenograft tumour was established in mice, the tumour volume was determined and the expressions of METTL3, miR‐589‐5p, MMP‐2, TIMP‐2, E‐cadherin, N‐cadherin and Vimentin in tumour tissue were detected by RT‐qPCR and Western blotting. In vitro study showed that miR‐589‐5p and METTL3 were highly expressed in liver cancer. METTL3 was positively correlated with miR‐589‐5p. METTL3 up‐regulated the expression of miR‐589‐5p and promoted the maturation of miR‐589‐5p. Overexpressed miR‐589‐5p and METTL3 promoted the viability, migration and invasion of liver cancer cells, while the effects of silencing miR‐589‐5p and METTL3 on the cells were the opposite. The effects of METTL3 overexpression and silencing were reversed by miR‐589‐5p inhibitor and mimic, respectively. In vivo study showed that METLL3 silencing inhibited the growth of xenograft tumour and the expressions of METTL3, MMP‐2, N‐cadherin and Vimentin, promoted the expressions of TIMP‐2 and E‐cadherin, while miR‐589‐5p mimic caused the opposite results and further reversed the effects of METLL3 silencing. In summary, this study found that METTL3‐mediated maturation of miR‐589‐5p promoted the malignant development of liver cancer.     

Characterization of a novel microfluidic platform for the isolation of rare single cells to enable CTC analysis from head and neck squamous cell carcinoma patients

Detailed examination of tumor components is leading‐edge to establish personalized cancer therapy. Accompanying research on cell‐free DNA, the cell count of circulating tumor cells (CTCs) in patient blood is seen as a crucial prognostic factor. The potential of CTC analysis is further not limited to the determination of the overall survival rate but sheds light on understanding inter‐ and intratumoral heterogeneity. In this regard, commercial CTC isolation devices combining an efficient enrichment of rare cells with a droplet deposition of single cells for downstream analysis are highly appreciated. The Liquid biopsy platform CTCelect was developed to realize a fully‐automated enrichment and single cell dispensing of CTCs from whole blood without pre‐processing. We characterized each process step with two different carcinoma cell lines demonstrating up to 87 % enrichment (n = 10) with EpCAM coupled immunomagnetic beads, 73 % optical detection and dispensing efficiency (n = 5). 40 to 56.7 % of cells were recovered after complete isolation from 7.5 ml untreated whole blood (n = 6). In this study, CTCelect enabled automated dispensing of single circulating tumor cells from HNSCC patient samples, qPCR‐based confirmation of tumor‐related biomarkers and immunostaining. Finally, the platform was compared to commercial CTC isolation technologies to highlight advantages and limitations of CTCelect. This system offers new possibilities for single cell screening in cancer diagnostics, individual therapy approaches and real‐time monitoring.     

Safety and feasibility of umbilical cord mesenchymal stem cells in patients with COVID‐19 pneumonia: A pilot study

ObjectivesWe aim to explore the safety and feasibility of umbilical cord mesenchymal stem cells (UC‐MSCs) transplantation in patients with severe and critically severe coronavirus disease‐2019 (COVID‐19).MethodsWe conducted a small sample, single arm, pilot trial. In addition to standard therapy, we performed four rounds of transplantation of UC‐MSCs in sixteen patients with severe and critically severe COVID‐19. We recorded adverse events from enrolment to Day 28. We evaluated the oxygenation index, inflammatory biomarkers, radiological presentations of the disease and lymphocyte subsets count on the 7th day (D7 ± 1 day), the 14th day (D14 ± 1 day) and the 28th day (D28 ± 3 days).ResultsThere were no infusion‐related or allergic reactions. The oxygenation index was improved after transplantation. The mortality of enrolled patients was 6.25%, whereas the historical mortality rate was 45.4%. The level of cytokines estimated varied in the normal range, the radiological presentations (ground glass opacity) were improved and the lymphocyte count and lymphocyte subsets (CD4⁺ T cells, CD8⁺ T cells and NK cells) count showed recovery after transplantation.ConclusionsIntravenous transplantation of UC‐MSCs was safe and feasible for treatment of patients with severe and critically severe COVID‐19 pneumonia.     

Encapsulating Non-Human Primate Multipotent Stromal Cells in Alginate via High Voltage for Cell-Based Therapies and Cryopreservation

Alginate cell-based therapy requires further development focused on clinical application. To assess engraftment, risk of mutations and therapeutic benefit studies should be performed in an appropriate non-human primate model, such as the common marmoset (Callithrix jacchus). In this work we encapsulated amnion derived multipotent stromal cells (MSCs) from Callithrix jacchus in defined size alginate beads using a high voltage technique. Our results indicate that i) alginate-cell mixing procedure and cell concentration do not affect the diameter of alginate beads, ii) encapsulation of high cell numbers (up to 10×10⁶ cells/ml) can be performed in alginate beads utilizing high voltage and iii) high voltage (15–30 kV) does not alter the viability, proliferation and differentiation capacity of MSCs post-encapsulation compared with alginate encapsulated cells produced by the traditional air-flow method. The consistent results were obtained over the period of 7 days of encapsulated MSCs culture and after cryopreservation utilizing a slow cooling procedure (1 K/min). The results of this work show that high voltage encapsulation can further be maximized to develop cell-based therapies with alginate beads in a non-human primate model towards human application.     

Enhanced nuclear localization of YAP1‐2 contributes to EGF‐induced EMT in NSCLC

YAP1, a key mediator of the Hippo pathway, plays an important role in tumorigenesis. Alternative splicing of human YAP1 mRNA results in two major isoforms: YAP1‐1, which contains a single WW domain, and YAP1‐2, which contains two WW domains, respectively. We here investigated the functions and the underlying regulatory mechanisms of the two YAP1 isoforms in the context of EGF‐induced epithelial‐mesenchymal transition (EMT) in non‐small cell lung cancer (NSCLC). Human NSCLC cell lines express both YAP1‐1 and YAP1‐2 isoforms—although when compared to YAP1‐1, YAP1‐2 mRNA levels are higher while its protein expression levels are lower. EGF treatment significantly promoted YAP1 expression as well as EMT process in NSCLCs, whereas EGF‐induced EMT phenotype was significantly alleviated upon YAP1 knockdown. Under normal culture condition, YAP1‐1 stable expression cells exhibited a stronger migration ability than YAP1‐2 expressing cells. However, upon EGF treatment, YAP1‐2 stable cells showed more robust migration than YAP1‐1 expressing cells. The protein stability and nuclear localization of YAP1‐2 were preferentially enhanced with EGF treatment. Moreover, EGF‐induced EMT and YAP1‐2 activity were suppressed by inhibitor of AKT. Our results suggest that YAP1‐2 is the main isoform that is functionally relevant in promoting EGF‐induced EMT and ultimately NSCLC progression.     

Remifentanil up‐regulates HIF1α expression to ameliorate hepatic ischaemia/reperfusion injury via the ZEB1/LIF axis

Ischaemia/reperfusion (I/R)‐induced hepatic injury is regarded as a main reason of hepatic failure after transplantation or lobectomy. The current study aimed to investigate how the opioid analgesic remifentanil treatment affects I/R‐induced hepatic injury and explore the possible mechanisms related to HIF1α. Initially, an I/R‐induced hepatic injury animal model was established in C57BL/6 mice, and an in vitro hypoxia‐reoxygenation model was constructed in NCTC‐1469 cells, followed by remifentanil treatment and HIF1α silencing treatment. The levels of blood glucose, lipids, alanine transaminase (ALT) and aspartate transaminase (AST) in mouse serum were measured using automatic chemistry analyser, while the viability and apoptosis of cells were detected using CCK8 assay and flow cytometry. Our results revealed that mice with I/R‐induced hepatic injury showed higher serum levels of blood glucose, lipids, ALT and AST and leukaemia inhibitory factor (LIF) expression, and lower HIF1α and ZEB1 expression (P < .05), which were reversed after remifentanil treatment (P < .05). Besides, HIF1α silencing increased the serum levels of blood glucose, lipids, ALT and AST (P < .05). Furthermore, hypoxia‐induced NCTC‐1469 cells exhibited decreased HIF1α and ZEB1 expression, reduced cell viability, as well as increased LIF expression and cell apoptosis (P < .05), which were reversed by remifentanil treatment (P < .05). Moreover, HIF1α silencing down‐regulated ZEB1 expression, decreased cell viability, and increased cell apoptosis (P < .05). ZEB1 was identified to bind to the promoter region of LIF and inhibit its expression. In summary, remifentanil protects against hepatic I/R injury through HIF1α and downstream effectors.     

Genetic association study of intron variants in the forkhead box protein P3 gene in Chinese patients diagnosed with cervical cancer

The aim of this study was to investigate the effects of forkhead box protein P3 (FOXP3) intron single nucleotide variants (SNVs) in high‐risk human papilloma virus (HR‐HPV) infection and cervical cancer (CC) malignant lesions. We performed FOXP3 genotyping in 350 patients with CC and 350 healthy controls using the ImLDR multiple single nucleotide polymorphism genotyping technology. The heterozygous mutation TC in rs2294021 decreased the risk of HR‐HPV infection and CC malignant lesions (TC vs. TT: OR = 0.71, 95% CI = 0.51–0.99); the dominant model TC+CC and allele C in rs2294021 decreased the risk of CC malignant lesions (TC+CC vs. TT: OR = 0.69, 95% CI = 0.50–0.95; C vs. T: OR = 0.78, 95% CI = 0.63–0.97). The heterozygous mutation GA, dominant model GA+AA and allele A in rs3761549 also decreased the risk of HR‐HPV infection and CC malignant lesions (GA vs. GG: OR = 0.70, 95% CI = 0.51–0.96; GA+AA vs. GG: OR = 0.69, 95% CI = 0.51–0.94; A vs. G: OR = 0.75, 95% CI = 0.58–0.96). Patients with CC and HR‐HPV infection carrying rs2294021 TC and rs3761549 GA had lower expression of FOXP3 protein. Haplotype analysis revealed that T‐C‐A decreased the risk of HR‐HPV infection. Furthermore, we found a significant association between immune cells infiltration and prognosis in patients with CC. Our findings demonstrated that rs2294021 and rs3761549 variants may protect against HR‐HPV and CC malignant lesions by downregulating FOXP3 and that FOXP3 was associated with immune cells infiltration, which affected the prognosis of CC.     

IFN‐γ+IL‐17+Th17 cells regulate fibrosis through secreting IL‐21 in systemic scleroderma

This study aimed to explore the function of IFN‐γ⁺IL‐17⁺Th17 cells on fibrosis in systemic scleroderma (SSc). Blood and skin samples were collected from 20 SSc cases and 10 healthy individuals. The percentage of IFN‐γ⁺IL‐17⁺Th17 cells was detected using flow cytometry. The in vitro induction of IFN‐γ⁺IL‐17⁺Th17 cells was performed adopting PHA and rIL‐12. Gene expression was detected via quantitative real‐time polymerase chain reaction (qRT‐PCR), whereas western blot analysis was adopted for protein analysis. The distribution of IFN‐γ⁺IL‐17⁺Th17 cells was significantly increased in SSc cases and positively correlated with SSc stages (P = .031), disease duration (P = .016), activity (P = .025) and skin scores (P < .001). In vitro, IFN‐γ⁺IL‐17⁺Th17 cells could promote the expressions of α‐SMA and COL1A1, revealing increased fibroblasts’ proliferation and enhanced collagen‐secreting capacity. In addition, IL‐21 expression was significantly increased in co‐culture medium of IFN‐γ⁺IL‐17⁺Th17 cells and fibroblasts (P < .001). IL‐21 neutralizer treatment resulted in the down‐regulation of α‐SMA and COL1A1. IL‐21 was confirmed as an effector of IFN‐γ⁺IL‐17⁺Th17 cells in fibrosis process. The distribution of IFN‐γ⁺IL‐17⁺Th17 cells was significantly increased in SSc cases and positively correlated with disease activity. IFN‐γ⁺IL‐17⁺Th17 cells could promote fibroblast proliferation and enhance collagen‐secreting ability via producing IL‐21, thus contributing to fibrosis in SSc.     

LRP5 promotes cancer stem cell traits and chemoresistance in colorectal cancer

The overactivation of canonical Wnt/β‐catenin pathway and the maintenance of cancer stem cells (CSCs) are essential for the onset and malignant progression of most human cancers. However, their regulatory mechanism in colorectal cancer (CRC) has not yet been well demonstrated. Low‐density lipoprotein receptor‐related protein 5 (LRP5) has been identified as an indispensable co‐receptor with frizzled family members for the canonical Wnt/β‐catenin signal transduction. Herein, we show that activation of LRP5 gene promotes CSCs‐like phenotypes, including tumorigenicity and drug resistance in CRC cells, through activating the canonical Wnt/β‐catenin and IL‐6/STAT3 signalling pathways. Clinically, the expression of LRP5 is upregulated in human CRC tissues and closely associated with clinical stages of patients with CRC. Further analysis showed silencing of endogenous LRP5 gene is sufficient to suppress the CSCs‐like phenotypes of CRC through inhibiting these two pathways. In conclusion, our findings not only reveal a regulatory cross‐talk between canonical Wnt/β‐catenin signalling pathway, IL‐6/STAT3 signalling pathway and CD133‐related stemness that promote the malignant behaviour of CRC, but also provide a valuable target for the diagnosis and treatment of CRC.     

Alginate-encapsulation of shoot tips of jojoba [Simmondsia chinensis (Link) Schneider] for germplasm exchange and distribution

Shoot tips excised from in vitro proliferated shoots derived from nodal explants of jojoba [Simmondsia chinensis (Link) Schneider] were encapsulated in calcium alginate beads for germplasm exchange and distribution. A gelling matrix of 3 % sodium alginate and 100 mM calcium chloride was found most suitable for formation of ideal calcium alginate beads. Best response for shoot sprouting from encapsulated shoot tips was recorded on 0.8 % agar-solidified full-strength MS medium. Rooting was induced upon transfer of sprouted shoots to 0.8 % agar-solidified MS medium containing 1 mg l⁻¹ IBA. About 70 % of encapsulated shoot tips were rooted and converted into plantlets. Plants regenerated from encapsulated shoot tips were acclimatized successfully. The present encapsulation approach could also be applied as an alternative method of propagation of desirable elite genotype of jojoba.     

C1632 suppresses the migration and proliferation of non‐small‐cell lung cancer cells involving LIN28 and FGFR1 pathway

Chemoresistance and migration represent major obstacles in the therapy of non‐small‐cell lung cancer (NSCLC), which accounts for approximately 85% of lung cancer patients in clinic. In the present study, we report that the compound C1632 is preferentially distributed in the lung after oral administration in vivo with high bioavailability and limited inhibitory effects on CYP450 isoenzymes. We found that C1632 could simultaneously inhibit the expression of LIN28 and block FGFR1 signalling transduction in NSCLC A549 and A549R cells, resulting in significant decreases in the phosphorylation of focal adhesion kinase and the expression of matrix metalloproteinase‐9. Consequently, C1632 effectively inhibited the migration and invasion of A549 and A549R cells. Meanwhile, C1632 significantly suppressed the cell viability and the colony formation of A549 and A549R cells by inhibiting DNA replication and inducing G0/G1 cell cycle arrest. Interestingly, compared with A549 cells, C1632 possesses the same or even better anti‐migration and anti‐proliferation effects on A549R cells, regardless of drug resistance. In addition, C1632 also displayed the capacity to inhibit the growth of A549R xenograft tumours in mice. Altogether, these findings reveal the potential of C1632 as a promising anti‐NSCLC agent, especially for chemotherapy‐resistant NSCLC treatment.     

Aneuploid senescent cells activate NF‐κB to promote their immune clearance by NK cells

The immune system plays a major role in the protection against cancer. Identifying and characterizing the pathways mediating this immune surveillance are thus critical for understanding how cancer cells are recognized and eliminated. Aneuploidy is a hallmark of cancer, and we previously found that untransformed cells that had undergone senescence due to highly abnormal karyotypes are eliminated by natural killer (NK) cells in vitro. However, the mechanisms underlying this process remained elusive. Here, using an in vitro NK cell killing system, we show that non‐cell‐autonomous mechanisms in aneuploid cells predominantly mediate their clearance by NK cells. Our data indicate that in untransformed aneuploid cells, NF‐κB signaling upregulation is central to elicit this immune response. Inactivating NF‐κB abolishes NK cell‐mediated clearance of untransformed aneuploid cells. In cancer cell lines, NF‐κB upregulation also correlates with the degree of aneuploidy. However, such upregulation in cancer cells is not sufficient to trigger NK cell‐mediated clearance, suggesting that additional mechanisms might be at play during cancer evolution to counteract NF‐κB‐mediated immunogenicity.     

Comparative proteome analysis identified CD44 as a possible serum marker for docetaxel resistance in castration‐resistant prostate cancer

Baseline or acquired resistance to docetaxel (DOC) represents a significant risk for patients with metastatic prostate cancer (PC). In the last years, novel therapy regimens have been approved providing reasonable alternatives for DOC‐resistant patients making prediction of DOC resistance of great clinical importance. We aimed to identify serum biomarkers, which are able to select patients who will not benefit from DOC treatment. DOC‐resistant PC3‐DR and DU145‐DR sublines and their sensitive parental cell lines (DU145, PC3) were comparatively analyzed using liquid chromatography‐coupled tandem mass spectrometry (LC‐MS/MS). Results were filtered using bioinformatics approaches to identify promising serum biomarkers. Serum levels of five proteins were determined in serum samples of 66 DOC‐treated metastatic castration‐resistant PC patients (mCRPC) using ELISA. Results were correlated with clinicopathological and survival data. CD44 was subjected to further functional cell culture analyses. We found at least 177 two‐fold significantly overexpressed proteins in DOC‐resistant cell lines. Our bioinformatics method suggested 11/177 proteins to be secreted into the serum. We determined serum levels of five (CD44, MET, GSN, IL13RA2 and LNPEP) proteins in serum samples of DOC‐treated patients and found high CD44 serum levels to be independently associated with poor overall survival (p = 0.001). In accordance, silencing of CD44 in DU145‐DR cells resulted in re‐sensitization to DOC. In conclusion, high serum CD44 levels may help identify DOC‐resistant patients and may thereby help optimize clinical decision‐making regarding type and timing of therapy for mCRPC patients. In addition, our in vitro results imply the possible functional involvement of CD44 in DOC resistance.