Clinical severity in Parkinson's disease is determined by decline in cortical compensation.

Dopaminergic dysfunction in the basal ganglia, particularly in the posterior putamen, is often viewed as the primary pathological mechanism behind motor slowing (i.e. bradykinesia) in Parkinson's disease. However, striatal dopamine loss fails to account for interindividual differences in motor phenotype and rate of decline, implying that the expression of motor symptoms depends on additional mechanisms, some of which may be compensatory in nature. Building on observations of increased motor-related activity in the parieto-premotor cortex of Parkinson patients, we tested the hypothesis that interindividual differences in clinical severity are determined by compensatory cortical mechanisms and not just by basal ganglia dysfunction. Using functional MRI, we measured variability in motor- and selection-related brain activity during a visuomotor task in 353 patients with Parkinson's disease (≤5 years disease duration) and 60 healthy controls. In this task, we manipulated action selection demand by varying the number of possible actions that individuals could choose from. Clinical variability was characterized in two ways. First, patients were categorized into three previously validated, discrete clinical subtypes that are hypothesized to reflect distinct routes of α-synuclein propagation: diffuse-malignant (n = 42), intermediate (n = 128) or mild motor-predominant (n = 150). Second, we used the scores of bradykinesia severity and cognitive performance across the entire sample as continuous measures. Patients showed motor slowing (longer response times) and reduced motor-related activity in the basal ganglia compared with controls. However, basal ganglia activity did not differ between clinical subtypes and was not associated with clinical scores. This indicates a limited role for striatal dysfunction in shaping interindividual differences in clinical severity. Consistent with our hypothesis, we observed enhanced action selection-related activity in the parieto-premotor cortex of patients with a mild-motor predominant subtype, both compared to patients with a diffuse-malignant subtype and controls. Furthermore, increased parieto-premotor activity was related to lower bradykinesia severity and better cognitive performance, which points to a compensatory role. We conclude that parieto-premotor compensation, rather than basal ganglia dysfunction, shapes interindividual variability in symptom severity in Parkinson's disease. Future interventions may focus on maintaining and enhancing compensatory cortical mechanisms, rather than only attempting to normalize basal ganglia dysfunction.

Family History and Risk of Renal Cell Carcinoma: A National Multiregister Case-Control Study.

PURPOSE: Our purpose was to investigate the association between family history of renal cell carcinoma (RCC) and RCC risk. MATERIALS AND METHODS: RCC cases diagnosed in Sweden between 2005 and 2014 and 10 matched controls were identified using the Renal Cell Cancer Database Sweden, with linkage to the Multigeneration Register and the Swedish Cancer Registry. The association between a family history of RCC and RCC was investigated, overall and by sex and age groups. RESULTS: Among 9416 RCC cases, 294 (3.1%) had 1 or more parent or sibling (first-degree relative [FDR]) with RCC. Median age at diagnosis for cases with an affected FDR was 65 years (IQR 59-71) and 68 years (IQR 60-75) for all cases. The proportion of women was significantly higher among familial RCC compared to sporadic RCC (44.6% vs 38.5%, P = .035). RCC was twice as likely with 1 or more FDR with RCC (OR 1.9; CI 1.65-2.16). Stratified analysis showed an OR of 2.4 for women (CI 1.93-2.92) and 1.6 for men (CI 1.35-1.93). Two or more FDRs was associated with a sixfold increased risk (95% CI 2.37-15.5). Familial RCC was strongly associated with bilateral and multifocal tumors (OR 5.5; CI 2.36-13.0, OR 3.5; CI 1.89-6.49). CONCLUSIONS: In this Swedish data set, 3.1% of RCC patients have 1 or more FDR diagnosed with RCC. There was no statistical difference in median age between sporadic RCC and familial RCC. Having 1 or more FDR with RCC approximately doubles the risk of RCC with a higher risk increase for women than for men. People with 2 FDRs with RCC constitute a small high-risk group that may benefit from screening.

Itga8-Cre-mediated deletion of YAP and TAZ impairs bladder contractility with minimal inflammation and chondrogenic differentiation.

A role of Yes1-associated transcriptional regulator (YAP) and WW domain-containing transcription regulator 1 (TAZ) in vascular and gastrointestinal contractility due to control of myocardin (Myocd) expression, which in turn activates contractile genes, has been demonstrated. Whether this transcriptional hierarchy applies to the urinary bladder is unclear. We found that YAP/TAZ are expressed in human detrusor myocytes and therefore exploited the Itga8-CreERT2 model for the deletion of YAP/TAZ. Recombination occurred in detrusor, and YAP/TAZ transcripts were reduced by >75%. Bladder weights were increased (by ≈22%), but histology demonstrated minimal changes in the detrusor, while arteries in the mucosa were inflamed. Real-time quantitative reverse transcription PCR (RT-qPCR) using the detrusor demonstrated reductions of Myocd (-79 ± 18%) and serum response factor (Srf) along with contractile genes. In addition, the cholinergic receptor muscarinic 2 (Chrm2) and Chrm3 were suppressed (-80 ± 23% and -80 ± 10%), whereas minute increases of Il1b and Il6 were seen. Unlike YAP/TAZ-deficient arteries, SRY (sex-determining region Y)-box 9 (Sox9) did not increase, and no chondrogenic differentiation was apparent. Reductions of smooth muscle myosin heavy chain 11 (Myh11), myosin light-chain kinase gene (Mylk), and Chrm3 were seen at the protein level. Beyond restraining the smooth muscle cell (SMC) program of gene expression, YAP/TAZ depletion silenced SMC-specific splicing, including exon 2a of Myocd. Reduced contractile differentiation was associated with weaker contraction in response to myosin phosphatase inhibition (-36%) and muscarinic activation (reduced by 53% at 0.3 µM carbachol). Finally, short-term overexpression of constitutively active YAP in human embryonic kidney 293 (HEK293) cells increased myocardin (greater than eightfold) along with archetypal target genes, but contractile genes were unaffected or reduced. YAP and TAZ thus regulate myocardin expression in the detrusor, and this is important for SMC differentiation and splicing as well as for contractility.NEW & NOTEWORTHY This study addresses the hypothesis that YAP and TAZ have an overarching role in the transcriptional hierarchy in the smooth muscle of the urinary bladder by controlling myocardin expression. Using smooth muscle-specific and inducible deletion of YAP and TAZ in adult mice, we find that YAP and TAZ control myocardin expression, contractile differentiation, smooth muscle-specific splicing, and bladder contractility. These effects are largely independent of inflammation and chondrogenic differentiation.

The injury-induced transcription factor SOX9 alters the expression of LBR, HMGA2, and HIPK3 in the human kidney.

Induction of SRY box transcription factor 9 (SOX9) has been shown to occur in response to kidney injury in rodents, where SOX9-positive cells proliferate and regenerate the proximal tubules of injured kidneys. Additionally, SOX9-positive cells demonstrate a capacity to differentiate toward other nephron segments. Here, we characterized the role of SOX9 in normal and injured human kidneys. SOX9 expression was found to colocalize with a proportion of so-called scattered tubular cells in the uninjured kidney, a cell population previously shown to be involved in kidney injury and regeneration. Following injury and in areas adjacent to inflammatory cell infiltrates, SOX9-positive cells were increased in number. With the use of primary tubular epithelial cells (PTECs) obtained from human kidney tissue, SOX9 expression was spontaneously induced in culture and further increased by transforming growth factor-ß1, whereas it was suppressed by interferon-γ. siRNA-mediated knockdown of SOX9 in PTECs followed by analysis of differential gene expression, immunohistochemical expression, and luciferase promoter assays suggested lamin B receptor (LBR), high mobility group AT-hook 2 (HMGA2), and homeodomain interacting protein kinase 3 (HIPK3) as possible target genes of SOX9. Moreover, a kidney explant model was used to demonstrate that only SOX9-positive cells survive the massive injury associated with kidney ischemia and that the surviving SOX9-positive cells spread and repopulate the tubules. Using a wound healing assay, we also showed that SOX9 positively regulated the migratory capacity of PTECs. These findings shed light on the functional and regulatory aspects of SOX9 activation in the human kidney during injury and regeneration.NEW & NOTEWORTHY Recent studies using murine models have shown that SRY box transcription factor 9 (SOX9) is activated during repair of renal tubular cells. In this study, we showed that SOX9-positive cells represent a proportion of scattered tubular cells found in the uninjured human kidney. Furthermore, we suggest that expression of LBR, HMGA2, and HIPK3 is altered by SOX9 in the kidney tubular epithelium, suggesting the involvement of these gene products in kidney injury and regeneration.

Aerobic Exercise Alters Brain Function and Structure in Parkinson's Disease: A Randomized Controlled Trial.

OBJECTIVE: Randomized clinical trials have shown that aerobic exercise attenuates motor symptom progression in Parkinson's disease, but the underlying neural mechanisms are unclear. Here, we investigated how aerobic exercise influences disease-related functional and structural changes in the corticostriatal sensorimotor network, which is involved in the emergence of motor deficits in Parkinson's disease. Additionally, we explored effects of aerobic exercise on tissue integrity of the substantia nigra, and on behavioral and cerebral indices of cognitive control. METHODS: The Park-in-Shape trial is a single-center, double-blind randomized controlled trial in 130 Parkinson's disease patients who were randomly assigned (1:1 ratio) to aerobic exercise (stationary home trainer) or stretching (active control) interventions (duration = 6 months). An unselected subset from this trial (exercise, n = 25; stretching, n = 31) underwent resting-state functional and structural magnetic resonance imaging (MRI), and an oculomotor cognitive control task (pro- and antisaccades), at baseline and at 6-month follow-up. RESULTS: Aerobic exercise, but not stretching, led to increased functional connectivity of the anterior putamen with the sensorimotor cortex relative to the posterior putamen. Behaviorally, aerobic exercise also improved cognitive control. Furthermore, aerobic exercise increased functional connectivity in the right frontoparietal network, proportionally to fitness improvements, and it reduced global brain atrophy. INTERPRETATION: MRI, clinical, and behavioral results converge toward the conclusion that aerobic exercise stabilizes disease progression in the corticostriatal sensorimotor network and enhances cognitive performance. ANN NEUROL 2022;91:203-216.

Cerebellar Volume and Disease Staging in Parkinson's Disease: An ENIGMA-PD Study.

BACKGROUND: Increasing evidence points to a pathophysiological role for the cerebellum in Parkinson's disease (PD). However, regional cerebellar changes associated with motor and non-motor functioning remain to be elucidated. OBJECTIVE: To quantify cross-sectional regional cerebellar lobule volumes using three dimensional T1-weighted anatomical brain magnetic resonance imaging from the global ENIGMA-PD working group. METHODS: Cerebellar parcellation was performed using a deep learning-based approach from 2487 people with PD and 1212 age and sex-matched controls across 22 sites. Linear mixed effects models compared total and regional cerebellar volume in people with PD at each Hoehn and Yahr (HY) disease stage, to an age- and sex- matched control group. Associations with motor symptom severity and Montreal Cognitive Assessment scores were investigated. RESULTS: Overall, people with PD had a regionally smaller posterior lobe (dmax = -0.15). HY stage-specific analyses revealed a larger anterior lobule V bilaterally (dmax = 0.28) in people with PD in HY stage 1 compared to controls. In contrast, smaller bilateral lobule VII volume in the posterior lobe was observed in HY stages 3, 4, and 5 (dmax = -0.76), which was incrementally lower with higher disease stage. Within PD, cognitively impaired individuals had lower total cerebellar volume compared to cognitively normal individuals (d = -0.17). CONCLUSIONS: We provide evidence of a dissociation between anterior "motor" lobe and posterior "non-motor" lobe cerebellar regions in PD. Whereas less severe stages of the disease are associated with larger motor lobe regions, more severe stages of the disease are marked by smaller non-motor regions. © 2023 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.

SMAD4 haploinsufficiency in small intestinal neuroendocrine tumors.

BACKGROUND: Patients with small intestinal neuroendocrine tumors (SINETs) frequently present with lymph node and liver metastases at the time of diagnosis, but the molecular changes that lead to the progression of these tumors are largely unknown. Sequencing studies have only identified recurrent point mutations at low frequencies with CDKN1B being the most common harboring heterozygous mutations in less than 10% of all tumors. Although SINETs are genetically stable tumors with a low frequency of point mutations and indels, they often harbor recurrent hemizygous copy number alterations (CNAs) yet the functional implications of these CNA are unclear. METHODS: Utilizing comparative genomic hybridization (CGH) arrays we analyzed the CNA profile of 131 SINETs from 117 patients. Two tumor suppressor genes and corresponding proteins i.e. SMAD4, and CDKN1B, were further characterized using a tissue microarray (TMA) with 846 SINETs. Immunohistochemistry (IHC) was used to quantify protein expression in TMA samples and this was correlated with chromosome number evaluated with fluorescent in-situ hybridization (FISH). Intestinal tissue from a Smad4+/- mouse model was used to detect entero-endocrine cell hyperplasia with IHC. RESULTS: Analyzing the CGH arrays we found loss of chromosome 18q and SMAD4 in 71% of SINETs and that focal loss of chromosome 12 affecting the CDKN1B was present in 9.4% of SINETs. No homozygous loss of chromosome 18 was detected. Hemizygous loss of SMAD4, but not CDKN1B, significantly correlated with reduced protein levels but hemizygous loss of SMAD4 did not induce entero-endocrine cell hyperplasia in the Smad4+/- mouse model. In addition, patients with low SMAD4 protein expression in primary tumors more often presented with metastatic disease. CONCLUSIONS: Hemizygous loss of chromosome 18q and the SMAD4 gene is the most common genetic event in SINETs and our results suggests that this could influence SMAD4 protein expression and spread of metastases. Although SMAD4 haploinsufficiency alone did not induce tumor initiation, loss of chromosome 18 could represent an evolutionary advantage in SINETs explaining the high prevalence of this aberration. Functional consequences of reduced SMAD4 protein levels could hypothetically be a potential mechanism as to why loss of chromosome 18 appears to be clonally selected in SINETs.

Features of increased malignancy in eosinophilic clear cell renal cell carcinoma.

Clear cell renal cell carcinoma (ccRCC) is the most common form of renal cancer. Due to inactivation of the von Hippel-Lindau tumour suppressor, the hypoxia-inducible transcription factors (HIFs) are constitutively activated in these tumours, resulting in a pseudo-hypoxic phenotype. The HIFs induce the expression of genes involved in angiogenesis and cell survival, but they also reset the cellular metabolism to protect cells from oxygen and nutrient deprivation. ccRCC tumours are highly vascularized and the cytoplasm of the cancer cells is filled with lipid droplets and glycogen, resulting in the histologically distinctive pale (clear) cytoplasm. Intratumoural heterogeneity may occur, and in some tumours, areas with granular, eosinophilic cytoplasm are found. Little is known regarding these traits and how they relate to the coexistent clear cell component, yet eosinophilic ccRCC is associated with higher grade and clinically more aggressive tumours. In this study, we have for the first time performed RNA sequencing comparing histologically verified clear cell and eosinophilic areas from ccRCC tissue, aiming to analyse the characteristics of these cell types. Findings from RNA sequencing were confirmed by immunohistochemical staining of biphasic ccRCC. We found that the eosinophilic phenotype displayed a higher proliferative drive and lower differentiation, and we confirmed a correlation to tumours of higher stage. We further identified mutations of the tumour suppressor p53 (TP53) exclusively in the eosinophilic ccRCC component, where mTORC1 activity was also elevated. Also, eosinophilic areas were less vascularized, yet harboured more abundant infiltrating immune cells. The cytoplasm of clear cell ccRCC cells was filled with lipids but had very low mitochondrial content, while the reverse was found in eosinophilic tissue. We herein suggest possible transcriptional mechanisms behind these phenomena. © 2020 The Authors. The Journal of Pathology published by John Wiley & Sons, Ltd. on behalf of The Pathological Society of Great Britain and Ireland.

Localization and Regulation of Polymeric Ig Receptor in Healthy and Diseased Human Kidney.

The polymeric Ig receptor (PIgR) constitutes an important part of the immune system by mediating transcytosis of dimeric IgA into mucosal fluids. Although well studied in organs such as the intestine, the regulation and localization of PIgR in human kidney are incompletely characterized. Herein, using immunohistochemistry, we show that in healthy human kidneys, PIgR is expressed by the progenitor-like tubular scattered cells of the proximal tubules and by parietal epithelial cells of glomeruli. We further show that proximal tubular expression of PIgR becomes widespread during kidney disease, correlating to elevated levels of urinary secretory IgA. Urinary secretory IgA levels also correlated to the degree of tubular fibrosis, plasma creatinine, and urea levels. In addition, primary tubular cells were cultured to study the function and regulation of PIgR in vitro. Cellular PIgR expression was induced by conditioned medium from activated human leukocytes, as well as by inflammatory cytokines, whereas transforming growth factor-ß1 caused decreased expression. Furthermore, interferon-γ increased the transcytosis of dimeric IgA in cultured tubular cells. Finally, a correlation study of mRNA data from the Genotype-Tissue Expression portal indicated that PIGR mRNA expression in kidney correlates to the expression of TNFSF13, a cytokine involved in plasma cell class switching to IgA. These results indicate that PIgR induction is an integral part of the injury phenotype of renal tubular cells.

PRELP Enhances Host Innate Immunity against the Respiratory Tract Pathogen Moraxella catarrhalis.

Respiratory tract infections are one of the leading causes of mortality worldwide urging better understanding of interactions between pathogens causing these infections and the host. Here we report that an extracellular matrix component proline/arginine-rich end leucine-rich repeat protein (PRELP) is a novel antibacterial component of innate immunity. We detected the presence of PRELP in human bronchoalveolar lavage fluid and showed that PRELP can be found in alveolar fluid, resident macrophages/monocytes, myofibroblasts, and the adventitia of blood vessels in lung tissue. PRELP specifically binds respiratory tract pathogens Moraxella catarrhalis, Haemophilus influenzae, and Streptococcus pneumoniae, but not other bacterial pathogens tested. We focused our study on M. catarrhalis and found that PRELP binds the majority of clinical isolates of M. catarrhalis (n = 49) through interaction with the ubiquitous surface protein A2/A2H. M. catarrhalis usually resists complement-mediated serum killing by recruiting to its surface a complement inhibitor C4b-binding protein, which is also a ligand for PRELP. We found that PRELP competitively inhibits binding of C4b-binding protein to bacteria, which enhances membrane attack complex formation on M. catarrhalis and thus leads to increased serum sensitivity. Furthermore, PRELP enhances phagocytic killing of serum-opsonized M. catarrhalis by human neutrophils in vitro. Moreover, PRELP reduces Moraxella adherence to and invasion of human lung epithelial A549 cells. Taken together, PRELP enhances host innate immunity against M. catarrhalis through increasing complement-mediated attack, improving phagocytic killing activity of neutrophils, and preventing bacterial adherence to lung epithelial cells.

Moraxella catarrhalis Evades Host Innate Immunity via Targeting Cartilage Oligomeric Matrix Protein.

Moraxella catarrhalis is a respiratory tract pathogen commonly causing otitis media in children and acute exacerbations in patients suffering from chronic obstructive pulmonary disease. Cartilage oligomeric matrix protein (COMP) functions as a structural component in cartilage, as well as a regulator of complement activity. Importantly, COMP is detected in resident macrophages and monocytes, alveolar fluid, and the endothelium of blood vessels in lung tissue. We show that the majority of clinical isolates of M. catarrhalis (n = 49), but not other tested bacterial pathogens, bind large amounts of COMP. COMP interacts directly with the ubiquitous surface protein A2 of M. catarrhalis. Binding of COMP correlates with survival of M. catarrhalis in human serum by inhibiting bactericidal activity of the complement membrane attack complex. Moreover, COMP inhibits phagocytic killing of M. catarrhalis by human neutrophils. We further observed that COMP reduces bacterial adhesion and uptake by human lung epithelial cells, thus protecting M. catarrhalis from intracellular killing by epithelial cells. Taken together, our findings uncover a novel mechanism that M. catarrhalis uses to evade host innate immunity.

Papillary renal cell carcinoma-derived chemerin, IL-8, and CXCL16 promote monocyte recruitment and differentiation into foam-cell macrophages.

Papillary renal cell carcinoma (pRCC) is the second most common type of renal cell carcinoma. The only curative treatment available for pRCC is radical surgery. If the disease becomes widespread, neither chemo- nor radiotherapy will have therapeutic effect, hence further research on pRCC is of utmost importance. Histologically, pRCC is characterized by a papillary growth pattern with focal aggregation of macrophages of the foam cell phenotype. In other forms of cancer, a clear role for tumor-associated macrophages during cancer growth and progression has been shown. Although the presence of foamy macrophages is a histological hallmark of pRCC tumors, little is known regarding their role in pRCC biology. In order to study the interaction between pRCC tumor and myeloid cells, we established primary cultures from pRCC tissue. We show that human pRCC cells secrete the chemokines IL-8, CXCL16, and chemerin, and that these factors attract primary human monocytes in vitro. RNAseq data from The Cancer Genome Atlas confirmed a high expression of these factors in pRCC tissue. Conditioned medium from pRCC cultures induced a shift in human monocytes toward the M2 macrophage phenotype. In extended cultures, these macrophages became enlarged and loaded with lipids, adopting the foam cell morphology found in pRCC tissue. These results show for the first time that pRCC primary tumor cells secrete factors that attract and differentiate monocytes into anti-inflammatory tumor-associated macrophages with foam cell histology.

Injury induced expression of caveolar proteins in human kidney tubules - role of megakaryoblastic leukemia 1.

BACKGROUND: Caveolae are membrane invaginations measuring 50-100 nm. These organelles, composed of caveolin and cavin proteins, are important for cellular signaling and survival. Caveolae play incompletely defined roles in human kidneys. Induction of caveolin-1/CAV1 in diseased tubules has been described previously, but the responsible mechanism remains to be defined. METHODS: Healthy and atrophying human kidneys were stained for caveolar proteins, (caveolin 1-3 and cavin 1-4) and examined by electron microscopy. Induction of caveolar proteins was studied in isolated proximal tubules and primary renal epithelial cells. These cells were challenged with hypoxia or H2O2. Primary tubular cells were also subjected to viral overexpression of megakaryoblastic leukemia 1 (MKL1) and MKL1 inhibition by the MKL1 inhibitor CCG-1423. Putative coregulators of MKL1 activity were investigated by Western blotting for suppressor of cancer cell invasion (SCAI) and filamin A (FLNA). Finally, correlative bioinformatic studies of mRNA expression of caveolar proteins and MKL1 were performed. RESULTS: In healthy kidneys, caveolar proteins were expressed by the parietal epithelial cells (PECs) of Bowman's capsule, endothelial cells and vascular smooth muscle. Electron microscopy confirmed caveolae in the PECs. No expression was seen in proximal tubules. In contrast, caveolar proteins were expressed in proximal tubules undergoing atrophy. Caveolar proteins were also induced in cultures of primary epithelial tubular cells. Expression was not enhanced by hypoxia or free radical stress (H2O2), but proved sensitive to inhibition of MKL1. Viral overexpression of MKL1 induced caveolin-1/CAV1, caveolin-2/CAV2 and SDPR/CAVIN2. In kidney tissue, the mRNA level of MKL1 correlated with the mRNA levels for caveolin-1/CAV1, caveolin-2/CAV2 and the archetypal MKL1 target tenascin C (TNC), as did the MKL1 coactivator FLNA. Costaining for TNC as readout for MKL1 activity demonstrated overlap with caveolin-1/CAV1 expression in PECs as well as in atrophic segments of proximal tubules. CONCLUSIONS: Our findings support the view that MKL1 contributes to the expression of caveolar proteins in healthy kidneys and orchestrates the induction of tubular caveolar proteins in renal injury.

Clear Cell Adenocarcinoma of the Female Urethra: Four Case Presentations of a Clinical and Pathological Entity Requiring Radical Surgery.

Clear cell adenocarcinoma of the female urethra is a rare tumour of unknown origin. Here, we report 4 patients with such malignancy and argue for proper identification of the disease entity and radical surgery based on the available literature.

The role of PI3K/AKT-related PIP5K1α and the discovery of its selective inhibitor for treatment of advanced prostate cancer.

Nitrogen-containing heterocyclic compounds are an important class of molecules that are commonly used for the synthesis of candidate drugs. Phosphatidylinositol-4-phosphate 5-kinase-α (PIP5Kα) is a lipid kinase, similar to PI3K. However, the role of PIP5K1α in oncogenic processes and the development of inhibitors that selectively target PIP5K1α have not been reported. In the present study we report that overexpression of PIP5K1α is associated with poor prognosis in prostate cancer and correlates with an elevated level of the androgen receptor. Overexpression of PIP5K1α in PNT1A nonmalignant cells results in an increased AKT activity and an increased survival, as well as invasive malignant phenotype, whereas siRNA-mediated knockdown of PIP5K1α in aggressive PC-3 cells leads to a reduced AKT activity and an inhibition in tumor growth in xenograft mice. We further report a previously unidentified role for PIP5K1α as a druggable target for our newly developed compound ISA-2011B using a high-throughput KINOMEscan platform. ISA-2011B was discovered during our synthetic studies of C-1 indol-3-yl substituted 1,2,3,4-tetrahydroisoquinolines via a Pictet-Spengler approach. ISA-2011B significantly inhibits growth of tumor cells in xenograft mice, and we show that this is mediated by targeting PIP5K1α-associated PI3K/AKT and the downstream survival, proliferation, and invasion pathways. Further, siRNA-mediated knockdown of PIP5K1α exerts similar effects on PC3 cells as ISA-2011B treatment, significantly inhibiting AKT activity, increasing apoptosis and reducing invasion. Thus, PIP5K1α has high potential as a drug target, and compound ISA-2011B is interesting for further development of targeted cancer therapy.

Epigenetic regulation of the thioredoxin-interacting protein (TXNIP) gene by hyperglycemia in kidney.

Diabetic kidney disease is the leading cause of end-stage renal disease. Genetic factors have been suggested to contribute to its susceptibility. However, results from genetic studies are disappointing possibly because the role of glucose in diabetic kidney disease predisposed by epigenetic mechanisms has not been taken into account. Since thioredoxin-interacting protein (TXNIP) has been shown to play an important role in the pathogenesis of diabetic kidney disease, we tested whether glucose could induce expression of TXNIP in the kidney by epigenetic mechanisms. In kidneys from diabetic Sur1-E1506K(+/+) mice, hyperglycemia-induced Txnip expression was associated with stimulation of activating histone marks H3K9ac, H3K4me3, and H3K4me1, as well as decrease in the repressive histone mark H3K27me3 at the promoter region of the gene. Glucose also coordinated changes in histone marks and TXNIP gene expression in mouse SV40 MES13 mesangial cells and the normal human mesangial cell line NHMC. The involvement of histone acetylation in glucose-stimulated TXNIP expression was confirmed by reversing or enhancing acetylation using the histone acetyltransferase p300 inhibitor C646 or the histone deacetylase inhibitor trichostatin A. Thus, glucose is a potent inducer of histone modifications, which could drive expression of proinflammatory genes and thereby predispose to diabetic kidney disease.

Expression of functional toll like receptor 4 in estrogen receptor/progesterone receptor-negative breast cancer.

INTRODUCTION: Toll-like receptors (TLRs) are a family of pattern recognition receptors that are expressed on cells of the innate immune system. The ligands can be pathogen derived (pathogen associated molecular patterns; PAMPs) or endogenous (damage associated molecular patterns; DAMPs) that when bound induces activation of nuclear factor kappa B (NF-κB) and transcription of pro-inflammatory genes. TLRs have also been discovered in various malignant cell types, but with unknown function. METHODS: In this study we performed a detailed analysis of TLR and co-receptor expression pattern and function in breast cancer. Expression patterns were examined using real-time quantitative polymerase chain reaction (RT-qPCR) and immunohistochemistry (IHC) on three estrogen receptor-positive (ER(+)) and four estrogen receptor/progesterone receptor-negative (ER(-)/PR(-); ER/PR-negative) breast cancer cell lines, and a breast cancer cohort consisting of 144 primary breast cancer samples. The function was investigated using in vitro assays comprising PAMP/DAMP-stimulation, downstream signaling and TLR-silencing experiments. RESULTS: We found that TLR4 was expressed in a biologically active form and responded to both PAMPs and DAMPs primarily in ER/PR-negative breast cancers. Stimulation of TLR2/4 in vitro induced expression of pro-inflammatory genes and a gene expression analysis of primary breast cancers showed a strong correlation between TLR4 expression and expression of pro-inflammatory mediators. In line with this, TLR4 protein expression correlated with a decreased survival. CONCLUSIONS: These findings suggest that TLR4 is expressed in a functional form in ER/PR-negative breast cancers. Studies regarding TLR4-antagonist therapies should be focusing on ER/PR-negative breast cancer particularly.

Incidence and disease severity of anti-neutrophil cytoplasmic antibody-associated nephritis are higher than in lupus nephritis in Sweden.

OBJECTIVES: The objectives of this study were to compare incidence rates, renal and patient survival between lupus nephritis (LN) and anti-neutrophil cytoplasmic antibody-associated nephritis (AAN) during a 12-year period in two geographically defined populations in Sweden. METHODS: In the health care districts surrounding the Skåne University Hospital in Lund [mean population ≥18 years (1997-2008), 188 400] and the University Hospital in Linköping [mean population ≥18 years (1997-2008), 328 900] all patients with biopsy-proven LN and AAN during the period 1997-2008 were included in the study if they (i) were residing within the study areas at the time of onset of nephritis, (ii) had a clinical diagnosis of either SLE or ANCA-associated vasculitis (AAV) and (iii) experienced a first flare of biopsy-proven nephritis during the study period. RESULTS: Eighty-two patients (Lund 44 + Linköping 38) with biopsy-proven AAN were identified and 27 patients with LN (Lund 13 + Linköping 14). The annual incidence rate per million inhabitants aged ≥18 years in both study areas was estimated to be 13.2 (95% CI 10.4-16.1) for AAN and 4.3 (95% CI 2.7-6.0) for LN, P < 0.001. The patients were followed until January 2013. During the follow-up time 38 patients died (AAN 36, LN 2; P = 0.001), and 20 patients went into end-stage renal disease (AAN 19 and LN 1), P = 0.020. CONCLUSIONS: In Sweden, AAN was three times more common than LN, and the outcome was considerably worse. SLE is often diagnosed before the onset of nephritis leading to earlier treatment, while AAN is still often diagnosed at a later stage.

Renal stem cells and their implications for kidney cancer.

The renal cell carcinomas (RCC) denote a diverse set of neoplasias with unique genetic and histological features. The RCCs emanate from the renal tubule, a highly heterogeneous epithelial structure, and depending on which cell is malignified the resulting cancer displays unique characteristics. Notwithstanding this, the cells of origin for the RCC forms are far from established, and only inferred by the accumulated weight of marker similarities, not always providing an unequivocal picture. The tubular epithelium is normally mitotically quiescent, but demonstrates a considerable regenerative capacity upon renal injury. Recently the hypothesis that regeneration is driven by adult stem cells has been added experimental support, providing further complexity to the issue of renal carcinogenesis. Whether these cells are linked to RCC is an open question. In the present review we therefore present the prevailing theories regarding kidney regeneration, since a better understanding of this process might be of relevance when considering the different malignancies that arise from kidney epithelium. Our own results show that papillary renal cell carcinoma displays considerable similarities to proximal tubular progenitor cells and we suggest that this tumor form may develop in a multi-step fashion via benign renal adenomas. The putative connection between renal stem cells and carcinomas is, however, not clarified, since the current understanding of the renal stem cell system is not complete. It is clear that the efforts to isolate and characterize renal progenitor/stem cells suffer from numerous technical limitations and that it remains likely that the kidney harbors different stem cell pools with a restricted differentiation potential.

Tubular regeneration: when can the kidney regenerate from injury and what turns failure into success?

BACKGROUND: The most common intrarenal cause for acute kidney injury/renal failure is tubular damage. The kidney tubules are arranged as compartments of cellular mosaics to perform their functions, and at rest almost a fifth of the human ATP consumption is allotted to the reabsorption of substances from the filtrate, rendering especially the proximal tubules highly sensitive to oxygen and/or nutrient deprivation. Normally mitotically quiescent, the tubular epithelium shows a brisk regenerative response following injury if supportive care is offered, allowing functional restoration. Despite this, the cellular machinery behind the regenerative capacity is still not unequivocally defined. This is at odds with other epithelia such as those of the skin and intestine, where stem cells maintain a continuous flow of new cells from designated niches. SUMMARY: This review discusses the classical concept of renal regeneration, i.e. stochastically surviving cells undergoing dedifferentiation (or epithelial-mesenchymal transition) followed by replenishment of the tubular epithelium. Furthermore however, this view has recently been challenged by the concept of organ-confined stem/progenitor cells, bone marrow-derived stem cells, or mesenchymal stem cells taking part in the regenerative events. Whereas results from animal models support the classical view, morphologically distinct cells have been demonstrated in human kidneys, requiring interpretation. This review presents some of the previous work and techniques and highlights issues that need to be reconciled. KEY MESSAGES: In adult humans, the kidney tubules contain scattered cells with a distinct set of markers and properties, such as increased robustness during tubular damage. These cells may be induced by injury or represent a resident progenitor cell pool. To date, animal studies using lineage-tracing methods argue for an inductive scenario. In humans, the situation is less clear and one might speculate that the cellular heterogeneity might reflect elements of cellular reprogramming to a progenitor-like state, perhaps by induction. Due to intense investigational efforts, however, a scientific consensus may soon be reached, which will benefit further research.