Nuclear factor kappa-light-chain-enhancer of activated B cells gene expression involvement in porcine liver transplant experimental model.

PURPOSE: Gene expressions of vascular Endothelial Growth Factor Alpha (VEGFa), Nuclear Factor Kappa-Light-Chain-Enhancer of Activated B cells (NFkB) and cytokines could be useful for identifying potential therapeutic targets to alleviate ischemia-reperfusion injury after liver transplantation. Cytokine gene expressions, VEGFa and NFkB were investigated in a preclinical swine model of liver transplantation. METHODS: A total of 12 pigs were used as donors and recipients in liver transplantation without venovenous bypass or aortic clamping. NFkB, IL-6, IL-10, VEGFa and Notch1 gene expression were assessed. These samples were collected in two specific times: group 1 (n= 6) - control, samples were collected before recipient's total hepatectomy and group 2 - liver transplantation group (n=6), where the samples were collected one hour after graft reperfusion. RESULTS: Liver transplantation was successfully performed in all recipients. Liver enzymes were elevated in the transplantation group. NFkB gene expression was significantly decreased in the transplantation group in comparison with the control group (0.62±0.19 versus 0.39±0.08; p= 0.016). No difference was observed between groups Interleucine 6 (IL-6), interleucine 10 (IL-10), VEGFa and Notch homolog 1 (Notch1). CONCLUSIONS: In this survey a decreased NFkB gene expression in a porcine model of liver transplantation was observed.

Genetic variation in NOTCH1 is associated with overweight and obesity in Brazilian elderly.

Excessive weight (overweight and obesity) is a common disorder involving genetic and environmental factors, associated with cardiovascular diseases, type-2 diabetes, and others. NOTCH1 is critical for the maintenance of stem cells and adult tissues, being reported as a key player in metabolism and adipogenesis in animals. Thus, we test the hypothesis that NOTCH1 Single Nucleotide Polymorphisms (SNPs) are associated with excessive weight. Participants from the census-based cohort SABE (Saúde, Bem Estar e Envelhecimento-Health, Well-Being, and Aging), carried out in the city of São Paulo-Brazil, were stratified into cases and controls according to BMI. We filter the SNPs located at the start and end positions of NOTCH1 and 50 Kb on both sides. We selected SNPs with minor allelic frequency (MAF) greater than or equal to 0.01 and Hardy-Weinberg equilibrium (p > 0.05) and r2 ≥ 0.8. We performed an association study with genotypes and haplotypes, as well as in silico functional analysis of the identified SNPs. We observed an association of the SNP rs9411207 with the risk of excessive weight, under log-additive model, and the genotype distribution showed an increased frequency of homozygous TT (OR 1.50, CI 1.20-1.88; p = 0.0002). The haplotype GAT constructed from this and other SNPs in high Linkage Disequilibrium was more frequent in excessive-weight individuals (p = 0.003). In silico analyses suggested that these SNPs are likely to affect the transcription of NOTCH1 and other genes involved in adipogenesis and metabolism. This is the first study reporting association between NOTCH1 SNPs and the risk of excessive weight. Considering the possibility of NOTCH1 modulation, additional population studies are important to replicate these data and confirm the usefulness of risk genotypes for management strategies of excessive weight.

Regulation of Notch1 and Foxp1 by MiR-34a in psoriasis vulgaris / Regulación de Notch1 y Foxp1 por MiR-34ª en psoriasis vulgaris

SUMMARY: This study is to investigate the regulation of Notch1 and Foxp1 by miR-34a in the development of psoriasis vulgaris. RT-PCR was used to compare the levels of miR-34a in the skin lesions of 20 patients with psoriasis vulgaris and 20 normal skin tissues. Immunohistochemistry was used to detect the expression of Notch1 and Foxp1 in 51 patients with psoriasis vulgaris, which were further compared with that in 29 normal control tissues. In addition, in HaCaT cells, we used miR-34a mimics and inhibitors to overexpress and inhibit miR-34a, respectively, and detected the mRNA and protein levels of miR-34a, Notch1, and Foxp1. The level of miR-34a in the skin lesions of patients with psoriasis vulgaris was significantly higher than that in normal skin tissues (t=2.192, P<0.05). The positive rate of Notch1 in the skin lesions of patients with psoriasis vulgaris was 76.47 %, which was significantly higher than that in normal skin tissues (13.79 %) (t=29.215, P<0.01). The positive rate of FOXP1 in the psoriasis vulgaris group was 92.16 %, which was also significantly higher than that in the normal skin group (65.52 %) (t=9.087, P<0.01). In addition, overexpression of miR-34a significantly promoted the expression of Notch1 and Foxp1. However, inhibition of miR-34a significantly reduced Notch1 and Foxp1 levels. miR- 34a is highly expressed in the skin tissues of patients with psoriasis vulgaris, and may participate in the development of psoriasis vulgaris by regulating Notch1 and Foxp1.

RESUMEN: El objetivo de este estudio fue investigar la regulación de Notch1 y Foxp1 por miR-34a en el desarrollo de la psoriasis vulgar. Se utilizó RT-PCR con el fin de comparar los niveles de miR-34a en las lesiones cutáneas de 20 pacientes con psoriasis vulgar y 20 tejidos de piel normales. Se utilizó inmunohistoquímica para detectar la expresión de Notch1 y Foxp1 en 51 pacientes con psoriasis vulgar, que se compararon además con la de 29 tejidos normales control. Además, en las células HaCaT, usamos miméticos e inhibidores de miR-34a para sobreexpresar e inhibir miR-34a, respectivamente, y detectamos los niveles de ARNm y proteína de miR-34a, Notch1 y Foxp1. El nivel de miR- 34a en las lesiones cutáneas de pacientes con psoriasis vulgar fue significativamente mayor que en los tejidos normales de la piel (t=2,192, P<0,05). La tasa de positividad de Notch1 en las lesiones cutáneas de pacientes con psoriasis vulgar fue del 76,47 %, que fue significativamente mayor que la de los tejidos normales de la piel (13,79 %) (t=29,215, P<0,01). La tasa positiva de FOXP1 en el grupo de psoriasis vulgar fue del 92,16 %, que también fue significativamente mayor que la del grupo de piel normal (65,52 %) (t=9,087, P<0,01). Además, la sobreexpresión de miR-34a promovió significativamente la expresión de Notch1 y Foxp1. Sin embargo, la inhibición de miR-34a redujo de manera importante los niveles de Notch1 y Foxp1. miR-34a se expresa en gran medida en los tejidos de la piel en pacientes con psoriasis vulgar y puede participar en el desarrollo de la psoriasis vulgar mediante la regulación de Notch1 y Foxp1.

The deregulation of NOTCH pathway, inflammatory cytokines, and keratinization genes in two Dowling-Degos disease patients with hidradenitis suppurativa.

Dowling-Degos disease (DDD) is a rare autosomal-dominant genodermatosis and it has been associated with hidradenitis suppurativa (HS). Deregulation of NOTCH pathway has been linked to the development of HS in DDD context (DDD-HS). However, molecular alterations in DDD-HS, including altered gene expression of NOTCH and downstream effectors that are involved in the follicular differentiation and inflammatory response, are poorly defined. We report two cases of patients diagnosed with DDD-HS, one of those, under Adalimumab treatment. Our results have shown downregulation of NOTCH1/NCSTN pathway, distinct molecular profiles of inflammatory cytokines (IL23A and TNF), and a novel aberrant upregulation of genes involved in the cornified envelope (CE) formation (SPRR1B, SPRR2D, SPRR3, and IVL) in paired HS lesions of two DDD patients.

In vitro Notch-mediated adjuvant immunogenic potency is induced by combining QS-21 and MPL in a co-culture model of PBMC and HUVEC cells.

Few vaccine adjuvants have been approved for human use although several are currently being studied in preclinical and clinical trial. MPL is a toll-like receptor agonist able to trigger a high and persistent antibody response via-TLR-4 while QS-21 activates the NLRP3 inflammasome. Data suggest that there is a cross-talk between Notch and TLR signaling pathways modulating the polarization of the immune response in a MyD88-dependent manner. However, the role of Notch on the mechanism action of immunogenic adjuvants has not been addressed yet. This study aims to evaluate the in vitro toxicity and inflammatory response triggered by MPL and QS-21 using an in vitro human cell co-culture model and to determine whether NFκB or Notch signaling pathways are involved in their mechanism of immunotoxicity. In order to do this, we evaluated the effect of QS- 21/MPL alone or in combination using a co-culture of PBMC and HUVEC using cytotoxicity, surface expression of ECAMs, cell adhesion and cytokine release, NF-κB activation and NOTCH1 expression as observation endpoints. We found that both MPL and QS-21 were cytotoxic at concentrations over 5 µg/mL. Both adjuvants were able to trigger the expression of ECAMs and induce firm adhesion of PBMC to the endothelium. QS-21 and MPL combination demonstrated a synergistic effect on cellular recruitment and cytokine release generating a switch from Th2 to Th1 cytokine profile. Both MPL and QS-21 by themselves were able to generate significant NF-κB activation. However, this effect was not observed when both adjuvants were combined. On the contrary, the adjuvants alone and combined induced an overexpression of NOTCH-1. This is an important finding, as it provides new evidence that these adjuvants could modulate reactogenicity of vaccines through Notch signaling.

Calcific Aortic Valve Stenosis and Atherosclerotic Calcification.

PURPOSE OF REVIEW: This review summarizes the pathophysiology of calcific aortic valve stenosis (CAVS) and surveys relevant clinical data and basic research that explain how CAVS arises. RECENT FINDINGS: Lipoprotein(a) [Lp(a)], lipoprotein-associated phospholipase A2 (Lp-PLA2), oxidized phospholipids (OxPL), autotaxin, and genetic driving forces such as mutations in LPA gene and NOTCH gene seem to play a major role in the development of CAVS. These factors might well become targets of medical therapy in the coming years. CVAS seems to be a multifactorial disease that has much in common with coronary artery disease, mainly regarding lipidic accumulation and calcium deposition. No clinical trials conducted to date have managed to answer the key question of whether Lp(a) lowering and anti-calcific therapies confer a benefit in terms of reducing incidence or progression of CAVS, although additional outcome trials are ongoing.

Regenerative Effect of Growth Hormone (GH) in the Retina after Kainic Acid Excitotoxic Damage.

In addition to its role as an endocrine messenger, growth hormone (GH) also acts as a neurotrophic factor in the central nervous system (CNS), whose effects are involved in neuroprotection, axonal growth, and synaptogenic modulation. An increasing amount of clinical evidence shows a beneficial effect of GH treatment in patients with brain trauma, stroke, spinal cord injury, impaired cognitive function, and neurodegenerative processes. In response to injury, Müller cells transdifferentiate into neural progenitors and proliferate, which constitutes an early regenerative process in the chicken retina. In this work, we studied the long-term protective effect of GH after causing severe excitotoxic damage in the retina. Thus, an acute neural injury was induced via the intravitreal injection of kainic acid (KA, 20 µg), which was followed by chronic administration of GH (10 injections [300 ng] over 21 days). Damage provoked a severe disruption of several retinal layers. However, in KA-damaged retinas treated with GH, we observed a significant restoration of the inner plexiform layer (IPL, 2.4-fold) and inner nuclear layer (INL, 1.5-fold) thickness and a general improvement of the retinal structure. In addition, we also observed an increase in the expression of several genes involved in important regenerative pathways, including: synaptogenic markers (DLG1, NRXN1, GAP43); glutamate receptor subunits (NR1 and GRIK4); pro-survival factors (BDNF, Bcl-2 and TNF-R2); and Notch signaling proteins (Notch1 and Hes5). Interestingly, Müller cell transdifferentiation markers (Sox2 and FGF2) were upregulated by this long-term chronic GH treatment. These results are consistent with a significant increase in the number of BrdU-positive cells observed in the KA-damaged retina, which was induced by GH administration. Our data suggest that GH is able to facilitate the early proliferative response of the injured retina and enhance the regeneration of neurite interconnections.

HIF-1α is Overexpressed in Odontogenic Keratocyst Suggesting Activation of HIF-1α and NOTCH1 Signaling Pathways.

Background: The odontogenic keratocyst (OKC) is an odontogenic cyst that shows aggressive and intriguing biological behavior. It is suggested that a hypoxic environment occurs in OKC, which led us to investigate the immunoexpression and location of hypoxia-inducible factor 1-alpha (HIF-1α) and other hypoxia-related proteins. Methods: Twenty cases of OKC were evaluated for the expression of Notch homolog 1 (NOTCH1), HIF-1α, disintegrin and metalloproteinase domain-containing protein 12 (ADAM-12), and heparin-binding epidermal growth factor-like growth factor (HBEGF) by immunohistochemistry and compared to eight control cases of calcifying odontogenic cystic (COC), orthokeratinized odontogenic cyst (OOC), and normal oral mucosa (OM) in basal and parabasal layers. Results: In OKC, all the proteins tested were expressed significantly higher in both basal (except for NOTCH1 and HBEGF in OOC) and suprabasal epithelial layers compared to controls. Looking at the epithelial layers within OKC, we observed an increased NOTCH1 and HIF-1α expression in parabasal layers. Conclusions: These results suggest that hypoxia occurs more intensively in OKC compared to COC, OM, and OOC. Hypoxia appeared to be stronger in parabasal layers as observed by higher HIF-1α expression in upper cells. Overexpression of NOTCH1, ADAM-12, and HBEGF in OKC was observed, which suggests that microenvironmental hypoxia could potentially regulate the expression of hypoxia-related proteins, and consequently, its clinical and biological behavior.

CRLF2 expression associates with ICN1 stabilization in T-cell acute lymphoblastic leukemia.

T-cell acute lymphoblastic leukemia (T-ALL) is an aggressive hematopoietic malignancy with few molecular alterations showing a consensual prognostic value. CRLF2 overexpression was recently identified in high-risk T-ALL patients. For these cases, no genomic abnormality was found to be associated with CRLF2 overexpression. IKZF1 has been recently shown to be a direct transcriptional regulator of CRLF2 expression. Moreover, it is known that NOTCH1 antagonizes IKZF1 in T-ALL. In light of these pieces of evidence, we reasoned that IKZF1 binding perturbation and CRLF2 upregulation could be associated in T-ALL. We evaluated two independent series of pediatric T-ALL cases (PHOP, n = 57 and TARGET, n = 264) for the presence of common T-ALL molecular abnormalities, such as NOTCH1/FBXW7 mutations. We also assessed CRLF2 and IKZF1 gene expression. CRLF2 overexpression was observed in 14% (PHOP) and 16% (TARGET) of T-ALL patients. No correlation was found between mRNA expression of CRLF2 and IKZF1 in both cohorts. Interestingly, we show that patients with mutations affecting NOTCH1-PEST domain and/or FBXW7 had higher CRLF2 expression (P = .04). In summary, we demonstrate for the first time that only mutations resulting in ICN1 (intracellular domain of NOTCH1) stabilization are associated with CRLF2 overexpression.

HtrA1 suppresses the growth of pancreatic cancer cells by modulating Notch-1 expression

Pancreatic cancer is well known to be the most deadly malignancy with the worst survival rate of all cancers. High temperature requirement factor A1 (HtrA1) plays an important role in cancer cell proliferation, migration, apoptosis, and differentiation. This study aimed to explore the function of HtrA1 in pancreatic cancer cell growth and its underlying mechanism. We found that the expression of HtrA1 was lower in pancreatic cancer tissue compared to the adjacent normal tissue. Consistently, HtrA1 levels were also decreased in two human pancreatic cancer cell lines, PANC-1 and BXPC-3. Moreover, enforced expression of HtrA1 inhibited cell viability and colony formation of PANC-1 and BXPC-3 cells. Overexpression of HtrA1 promoted apoptosis and suppressed migratory ability of tumor cells. On the contrary, siRNA-mediated knockdown of HtrA1 promoted the growth potential of pancreatic cancer cells. In addition, we found that up-regulation of HtrA1 reduced the expression of Notch-1 in pancreatic cancer cells. On the contrary, knockdown of HtrA1 increased the expression levels of Notch-1. Furthermore, overexpression of Notch-1 abolished the anti-proliferative effect of HtrA1 on pancreatic cancer cells. Taken together, our findings demonstrated that HtrA1 could inhibit pancreatic cancer cell growth via regulating Notch-1 expression, which implied that HtrA1 might be developed as a novel molecular target for pancreatic cancer therapy.

HtrA1 suppresses the growth of pancreatic cancer cells by modulating Notch-1 expression.

Pancreatic cancer is well known to be the most deadly malignancy with the worst survival rate of all cancers. High temperature requirement factor A1 (HtrA1) plays an important role in cancer cell proliferation, migration, apoptosis, and differentiation. This study aimed to explore the function of HtrA1 in pancreatic cancer cell growth and its underlying mechanism. We found that the expression of HtrA1 was lower in pancreatic cancer tissue compared to the adjacent normal tissue. Consistently, HtrA1 levels were also decreased in two human pancreatic cancer cell lines, PANC-1 and BXPC-3. Moreover, enforced expression of HtrA1 inhibited cell viability and colony formation of PANC-1 and BXPC-3 cells. Overexpression of HtrA1 promoted apoptosis and suppressed migratory ability of tumor cells. On the contrary, siRNA-mediated knockdown of HtrA1 promoted the growth potential of pancreatic cancer cells. In addition, we found that up-regulation of HtrA1 reduced the expression of Notch-1 in pancreatic cancer cells. On the contrary, knockdown of HtrA1 increased the expression levels of Notch-1. Furthermore, overexpression of Notch-1 abolished the anti-proliferative effect of HtrA1 on pancreatic cancer cells. Taken together, our findings demonstrated that HtrA1 could inhibit pancreatic cancer cell growth via regulating Notch-1 expression, which implied that HtrA1 might be developed as a novel molecular target for pancreatic cancer therapy.

Notch1 is asymmetrically distributed from the beginning of embryogenesis and controls the ventral center.

Based on functional evidence, we have previously demonstrated that early ventral Notch1 activity restricts dorsoanterior development in Xenopus We found that Notch1 has ventralizing properties and abolishes the dorsalizing activity of ß-catenin by reducing its steady state levels, in a process that does not require ß-catenin phosphorylation by glycogen synthase kinase 3ß. In the present work, we demonstrate that Notch1 mRNA and protein are enriched in the ventral region from the beginning of embryogenesis in Xenopus This is the earliest sign of ventral development, preceding the localized expression of wnt8a, bmp4 and Ventx genes in the ventral center and the dorsal accumulation of nuclear ß-catenin. Knockdown experiments indicate that Notch1 is necessary for the normal expression of genes essential for ventral-posterior development. These results indicate that during early embryogenesis ventrally located Notch1 promotes the development of the ventral center. Together with our previous evidence, these results suggest that ventral enrichment of Notch1 underlies the process by which Notch1 participates in restricting nuclear accumulation of ß-catenin to the dorsal side.

Relationship between the expression of Notch1 and EZH2 and the prognosis of breast invasive ductal carcinoma.

We determined whether the coexpression of Notch1 and EZH2 influences the progression and prognosis of breast invasive ductal carcinoma. Using the χ(2) test, a significant difference was found between high and low expression of Notch1 in terms of lymph node, hormone receptor, and p53 expression (P < 0.05). Moreover, a significant difference was found between high and low expression of EZH2 in terms of tumor size, histologic grade, hormone receptor, and expression of Ki67 (P < 0.05). Using Pearson correlation analysis, we found a significant positive correlation between Notch1 and EZH2 expression in the tissue samples of breast invasive ductal carcinoma (P = 0.038). High Notch1 and EZH2 expression was associated with poor progression-free survival compared with low expression (PNotch1 = 0.000, 40.3 vs 48.9 months; PEZH2 = 0.000, 40.2 vs 49.9 months). Moreover, we found that high Notch1 and EZH2 expression was associated with poor overall survival compared with low expression (PNotch1 = 0.000, 51.2 vs 56.2 months; PEZH2 = 0.002, 51.7 vs 56.4 months). In conclusion, Notch1 and EZH2 coexpression contributes to the progression and prognosis of breast invasive ductal carcinoma.

A Novel Assay for the Identification of NOTCH1 PEST Domain Mutations in Chronic Lymphocytic Leukemia.

Aims. To develop a fast and robust DNA-based assay to detect insertions and deletions mutations in exon 34 that encodes the PEST domain of NOTCH1 in order to evaluate patients with chronic lymphocytic leukemia (CLL). Methods. We designed a multiplexed allele-specific polymerase chain reaction (PCR) combined with a fragment analysis assay to detect specifically the mutation c.7544_7545delCT and possibly other insertions and deletions in exon 34 of NOTCH1. Results. We evaluated our assay in peripheral blood samples from two cohorts of patients with CLL. The frequency of NOTCH1 mutations was 8.4% in the first cohort of 71 unselected CLL patients. We then evaluated a second cohort of 26 CLL patients with known cytogenetic abnormalities that were enriched for patients with trisomy 12. NOTCH1 mutations were detected in 43.7% of the patients with trisomy 12. Conclusions. We have developed a fast and robust assay combining allele-specific PCR and fragment analysis able to detect NOTCH1 PEST domain insertions and deletions.

NOTCH1, TP53, and MAP2K1 Mutations in Splenic Diffuse Red Pulp Small B-cell Lymphoma Are Associated With Progressive Disease.

Splenic diffuse red pulp small B-cell lymphoma (SDRPL) is considered an indolent neoplasm and its pathogenesis is not well known. We investigated the molecular characteristics of 19 SDRPL patients, 5 of them with progressive disease. IGHV genes were mutated in 9/13 (69%). Cytogenetic and molecular studies identified complex karyotypes in 2 cases, and IGH rearrangements in 3, with PAX5 and potentially TCL1 as partners in each one of them. Copy number arrays showed aberrations in 69% of the tumors, including recurrent losses of 10q23, 14q31-q32, and 17p13 in 3, and 9p21 in 2 cases. Deletion of 7q31.3-q32.3 was present in only 1 case and no trisomies 3 or 18 were detected. NOTCH1 and MAP2K1 were mutated in 2 cases each, whereas BRAF, TP53, and SF3B1 were mutated each in single cases. No mutations were found in NOTCH2 or MYD88. Four of the 5 patients with aggressive disease had mutations in NOTCH1 (2 cases), TP53 (1 case), and MAP2K1 (1 case). The progression-free survival of patients with mutated genes was significantly shorter than in the unmutated (P=0.011). These findings show that SDRPL share some mutated genes but not chromosomal alterations, with other splenic lymphomas, that may confer a more aggressive behavior.

A NOTCH1 gene copy number gain is a prognostic indicator of worse survival and a predictive biomarker to a Notch1 targeting antibody in colorectal cancer.

Dysregulation of the Notch1 receptor has been shown to facilitate the development and progression of colorectal cancer (CRC) and has been identified as an independent predictor of disease progression and worse survival. Although mutations in the NOTCH1 receptor have not been described in CRC, we have previously discovered a NOTCH1 gene copy number gain in a portion of CRC tumor samples. Here, we demonstrated that a NOTCH1 gene copy number gain is significantly associated with worse survival and a high percentage of gene duplication in a cohort of patients with advanced CRC. In our CRC patient-derived tumor xenograft (PDTX) model, tumors harboring a NOTCH1 gain exhibited significant elevation of the Notch1 receptor, JAG1 ligand and cleaved Notch1 activity. In addition, a significant association was identified between a gain in NOTCH1 gene copy number and sensitivity to a Notch1-targeting antibody. These findings suggest that patients with metastatic CRC that harbor a gain in NOTCH1 gene copy number have worse survival and that targeting this patient population with a Notch1 antibody may yield improved outcomes.

Protein O-Glucosyltransferase 1 (POGLUT1) Promotes Mouse Gastrulation through Modification of the Apical Polarity Protein CRUMBS2.

Crumbs family proteins are apical transmembrane proteins with ancient roles in cell polarity. Mouse Crumbs2 mutants arrest at midgestation with abnormal neural plate morphology and a deficit of mesoderm caused by defects in gastrulation. We identified an ENU-induced mutation, wsnp, that phenocopies the Crumbs2 null phenotype. We show that wsnp is a null allele of Protein O-glucosyltransferase 1 (Poglut1), which encodes an enzyme previously shown to add O-glucose to EGF repeats in the extracellular domain of Drosophila and mammalian Notch, but the role of POGLUT1 in mammalian gastrulation has not been investigated. As predicted, we find that POGLUT1 is essential for Notch signaling in the early mouse embryo. However, the loss of mouse POGLUT1 causes an earlier and more dramatic phenotype than does the loss of activity of the Notch pathway, indicating that POGLUT1 has additional biologically relevant substrates. Using mass spectrometry, we show that POGLUT1 modifies EGF repeats in the extracellular domain of full-length mouse CRUMBS2. CRUMBS2 that lacks the O-glucose modification fails to be enriched on the apical plasma membrane and instead accumulates in the endoplasmic reticulum. The data demonstrate that CRUMBS2 is the target of POGLUT1 for the gastrulation epithelial-to-mesenchymal transitions (EMT) and that all activity of CRUMBS2 depends on modification by POGLUT1. Mutations in human POGLUT1 cause Dowling-Degos Disease, POGLUT1 is overexpressed in a variety of tumor cells, and mutations in the EGF repeats of human CRUMBS proteins are associated with human congenital nephrosis, retinitis pigmentosa and retinal degeneration, suggesting that O-glucosylation of CRUMBS proteins has broad roles in human health.

Angiogenesis-related protein expression in bevacizumab-treated metastatic colorectal cancer: NOTCH1 detrimental to overall survival.

BACKGROUND: The development of targeted therapies has undoubtedly broadened therapeutic options for patients with colorectal cancer (CRC). The use of bevacizumab to reduce angiogenesis has been associated with improved clinical outcomes. However, an urgent need for prognostic/predictive biomarkers for anti-angiogenic therapies still exists. METHODS: Clinical data of 105 CRC patients treated with bevacizumab in conjunction with chemotherapy were analyzed. The expression of vascular endothelial growth factor (VEGF) receptors, NOTCH1 receptor and its ligand DLL4 were determined by immunohistochemistry. Tumor samples were arranged on a tissue microarray. The association between protein expression and clinicopathological characteristics and outcomes was determined. RESULTS: Bevacizumab was administered as a first-line of treatment in 70.5 % of our cases. The median progression-free survival (PFS) was 10.2 months. The median overall survival (OS) of the total cohort was 24.4 months. Bevacizumab, as the first-line of treatment, and the presence of liver metastasis were independently associated with objective response rate. Membrane VEGFR1 and VEGFR3 expressions were associated with the presence of lung metastasis; interestingly, VEGFR3 was associated with less liver metastasis. NOTCH1 expression was associated with lymph node metastasis. There was a trend toward association between improved PFS and lower NOTCH1 expression (p = 0.06). Improved OS was significantly associated with lower NOTCH1 expression (p = 0.01). In a multivariate analysis, ECOG (Eastern Cooperative Oncology Group) performance status, liver metastasis, histological grade, and NOTCH1 expression were independently associated with OS. CONCLUSION: Our findings illustrated the expression profile of angiogenesis-related proteins and their association with clinicopathological characteristics and outcomes. NOTCH1 expression is a detrimental prognostic factor in metastatic CRC patients treated with chemotherapy plus bevacizumab.

Notch1 and Notch2 in Podocytes Play Differential Roles During Diabetic Nephropathy Development.

Notch pathway activation in podocytes has been shown to play an important role in diabetic kidney disease (DKD) development; however, the receptors and ligands involved in the process have not been identified. Here, we report that conditional deletion of Notch1 in podocytes using NPHS2(cre)Notch1(flox/flox) animals resulted in marked amelioration of DKD. On the contrary, podocyte-specific genetic deletion of Notch2 had no effect on albuminuria and mesangial expansion. Notch1-null podocytes were protected from apoptosis and dedifferentiation in vitro, likely explaining the protective phenotype in vivo. Deletion of Notch1 in podocytes also resulted in an increase in Notch2 expression, indicating an interaction between the receptors. At the same time, transgenic overexpression of Notch2 in podocytes did not induce phenotypic changes, while constitutive expression of Notch1 caused rapid development of albuminuria and glomerulosclerosis. In summary, our studies indicate that Notch1 plays a distinct (nonredundant) role in podocytes during DKD development.

Isolation and characterization of cancer stem cells from medulloblastoma.

Brain cancer stem cells are a subset of tumor cells present in several types of brain tumor that evade treatment regimens and are responsible for tumor recurrence. Recent reports on several tumors have suggested that Hoechst 33342 dye exclusion is a powerful technique for isolating cancer stem cell-like side population (SP) cells. In the present study, we attempted to isolate the SP cells from medulloblastoma, a malignant brain tumor in children. The tumor samples obtained were subjected to fluorescence-activated cell sorting analysis for SP cell isolation. Further, the SP cells were characterized by a sphere-formation assay and analyzed for expression of stem cell genes by reverse transcription-polymerase chain reaction (RT-PCR). Using flow cytometry, we isolated 2.9% of cancer stem-like SP cells from malignant medulloblastoma, which was reduced to 0.4% in the presence of verapamil, an inhibitor of ABC transporter. These SP cells undergo rapid proliferation and have a high tendency to form tumor spheres when compared with non-SP cells. Further, RT-PCR analysis revealed that the isolated SP cells have increased expression of neural stem cell markers such as nestin, Notch1, and the ABC transporter protein ABCG2. Therefore, our findings suggest that SP cells of medulloblastoma share the characteristics of cancer stem cells. The increased expression of stem cell markers and ABCG2 protein may function collectively and be responsible for drug and apoptosis resistance, as well as tumor recurrence and invasion.