Modulation of Notch in an Animal Model of Multiple Sclerosis

Multiple Sclerosis (MS) is a neurodegenerative autoimmune disease that affects millions of people worldwide. Although the exact cause of MS is unknown, it is clear that CD4+ T helper cells play a significant role, namely T helper 1 (Th1) and T helper 17 (Th17) cells. The Notch family of proteins plays a role in the development and differentiation of T helper cells. Previous data has shown that inhibition of Notch impairs the ability of T helper cell differentiation. Additionally specific inhibition of certain Notch members inhibits specific T helper cell differentiation, for example the inhibition of Notch 1 inhibits Th1 and iTreg polarization [Samon et al., 2008]. However, the effects of the other Notch family members on CD4+ T cells are not fully studied. We propose that Notch 3 plays an extensive role in the regulation of Th1, Th2, Th17, and iTreg polarizations. In addition, we propose that Notch 3 regulates function of T helper cell function in the mouse model of MS, experimental autoimmune encephalomyelitis (EAE). Data in this thesis show that Notch 3 plays a significant role in the polarization of Th1, Th17 and iTreg polarization [Karlsson et al., 2011]. We present evidence that the heterozygous and homozygous Notch 3 knockout exhibits a significant decrease in polarization toward Th1, Th17 and iTreg cell fates. Exopolysaccharide (EPS) is a compound that has been previously shown to play a protective role in other inflammatory diseases. EPS has been shown to produce anti-inflammatory macrophages. We propose that a similar anti-inflammatory effect might be possible in EAE. We found that EPS had a significant effect on EAE induction, decreasing the onset and peak disease score. EPS also reduced the concentration of IFN-γ, IL17A, and GM-CSF in the supernatants of the splenocytes after restimulation with MOG. Further experimental data is needed to prove the effects of EPS on EAE and the method by which EPS function. These data indicate that Notch 3 could be crucial in regards to EAE due to the effects on Th1 and Th17 which are instrumental in EAE induction [Raphael et al., 2015]

Pool Toes: A Case Report.

Pool toes, a sport-related dermatosis, are caused by mechanical friction and water exposure, resulting in a special variant of irritant contact dermatitis. It is common in children, often misdiagnosed, and rarely reported. Here we report a case of a 7-year-old girl who developed this unusual type of frictional dermatitis; a pool toes diagnosis has been made. With topical corticosteroids, favorable results have been achieved. The recovery and healing process will be facilitated if one is aware of the underlying causes of such dermatitis and ceases the triggering factors

CCR6, the Sole Receptor for the Chemokine CCL20, Promotes Spontaneous Intestinal Tumorigenesis

Interactions between the inflammatory chemokine CCL20 and its receptor CCR6 have been associated with colorectal cancer growth and metastasis, however, a causal role for CCL20 signaling through CCR6 in promoting intestinal carcinogenesis has not been demonstrated in vivo. In this study, we aimed to determine the role of CCL20-CCR6 interactions in spontaneous intestinal tumorigenesis. CCR6-deficient mice were crossed with mice heterozygous for a mutation in the adenomatous polyposis coli (APC) gene (APCMIN/+ mice) to generate APCMIN/+ mice with CCR6 knocked out (CCR6KO-APCMIN/+ mice). CCR6KO-APCMIN/+ mice had diminished spontaneous intestinal tumorigenesis. CCR6KO-APCMIN/+ also had normal sized spleens as compared to the enlarged spleens found in APCMIN/+ mice. Decreased macrophage infiltration into intestinal adenomas and non-tumor epithelium was observed in CCR6KO-APCMIN/+ as compared to APCMIN/+ mice. CCL20 signaling through CCR6 caused increased production of CCL20 by colorectal cancer cell lines. Furthermore, CCL20 had a direct mitogenic effect on colorectal cancer cells. Thus, interactions between CCL20 and CCR6 promote intestinal carcinogenesis. Our results suggest that the intestinal tumorigenesis driven by CCL20-CCR6 interactions may be driven by macrophage recruitment into the intestine as well as proliferation of neoplastic epithelial cells. This interaction could be targeted for the treatment or prevention of malignancy

Long-Term Dose Optimization of Adalimumab via Dose Spacing in Patients with Psoriasis.

Dose spacing (DS) can be useful for optimizing treatment with biologics in psoriasis patients. However, interval prolongation might increase the production of anti-drug antibodies (ADA) and, therefore, reduce the drug's effectiveness. The long-term effects of DS with adalimumab in psoriatic patients have not been reported. The goal of our study was to evaluate the long-term follow-up of psoriatic patients after adalimumab DS regarding the clinical course and determination of circulating adalimumab, TNFα levels, and anti-adalimumab antibodies. We retrospectively included seven patients treated with adalimumab for moderate-to-severe psoriasis and benefiting from DS from 2010 to 2021. The dose interval of adalimumab was extended to three weeks for all patients and then to four weeks for three of the seven patients. Adalimumab trough levels, TNFα levels, and ADA against adalimumab were measured. For six of the seven patients, absolute PASI values remained below 3 throughout the follow-up period (median = 8.0 years; range: 1.7-11.5) after DS. All the patients were satisfied with the effectiveness of their treatment regime. Within the follow-up period, an average of 63 doses of adalimumab per patient were spared. The median adalimumab trough levels were 4.7 µg/mL (range: 1.9-12.5). TNFα levels remained under 10 pg/mL (undetectable) in all except one patient. ADA against adalimumab remained negative (<10 µg/mL) during the follow-up in all patients. Our data indicate that therapeutic drug monitoring, including the measurement of trough concentrations and ADA, together with the clinical response and patient's preference, can be helpful for clinical decision making and treatment optimization in psoriasis

Identification of novel myeloma-specific XBP1 peptides able to generate cytotoxic T lymphocytes: A potential therapeutic application in multiple myeloma

The purpose of these studies was to identify HLA-A2+ immunogenic peptides derived from XBP1 antigens to induce a multiple myeloma (MM)-specific immune response. Six native peptides from non-spliced XBP1 antigen and three native peptides from spliced XBP1 antigen were selected and evaluated for their HLA-A2 specificity. Among them,$XBP1_{184–192}$, XBP1 $SP_{196–204}$ and XBP1 $SP_{367–375}$ peptides showed the highest level of binding affinity, but not stability to HLA-A2 molecules. Novel heteroclitic XBP1 peptides, YISPWILAV or YLFPQLISV, demonstrated a significant improvement in HLA-A2 stability from their native $XBP1_{184–192}$ or XBP1 $SP_{367–375}$ peptide, respectively. Cytotoxic T lymphocytes generated by repeated stimulation of CD3+ T cells with each HLA-A2-specific heteroclitic peptide showed an increased percentage of CD8+ (cytotoxic) and CD69+/CD45RO+ (activated memory) T cells and a lower percentage of CD4+ (helper) and CD45RA+/CCR7+ (naïve) T cells, which were distinct from the control T cells. Functionally, the CTLs demonstrated MM-specific and HLA-A2-restricted proliferation, IFN-γ secretion and cytotoxic acivity in response to MM cell lines and importantly, cytotoxicty against primary MM cells. These data demonstrate the distinct immunogenic characteristics of unique heteroclitic XBP1 peptides which induce MM-specific CTLs and highlights their potential application for immunotherapy to treat the patients with MM or its pre-malignant condition

canEvolve: A Web Portal for Integrative Oncogenomics

Background & objective: Genome-wide profiles of tumors obtained using functional genomics platforms are being deposited to the public repositories at an astronomical scale, as a result of focused efforts by individual laboratories and large projects such as the Cancer Genome Atlas (TCGA) and the International Cancer Genome Consortium. Consequently, there is an urgent need for reliable tools that integrate and interpret these data in light of current knowledge and disseminate results to biomedical researchers in a user-friendly manner. We have built the canEvolve web portal to meet this need. Results: canEvolve query functionalities are designed to fulfill most frequent analysis needs of cancer researchers with a view to generate novel hypotheses. canEvolve stores gene, microRNA (miRNA) and protein expression profiles, copy number alterations for multiple cancer types, and protein-protein interaction information. canEvolve allows querying of results of primary analysis, integrative analysis and network analysis of oncogenomics data. The querying for primary analysis includes differential gene and miRNA expression as well as changes in gene copy number measured with SNP microarrays. canEvolve provides results of integrative analysis of gene expression profiles with copy number alterations and with miRNA profiles as well as generalized integrative analysis using gene set enrichment analysis. The network analysis capability includes storage and visualization of gene co-expression, inferred gene regulatory networks and protein-protein interaction information. Finally, canEvolve provides correlations between gene expression and clinical outcomes in terms of univariate survival analysis. Conclusion: At present canEvolve provides different types of information extracted from 90 cancer genomics studies comprising of more than 10,000 patients. The presence of multiple data types, novel integrative analysis for identifying regulators of oncogenesis, network analysis and ability to query gene lists/pathways are distinctive features of canEvolve. canEvolve will facilitate integrative and meta-analysis of oncogenomics datasets

Telomerase inhibition by siRNA causes senescence and apoptosis in Barrett's adenocarcinoma cells: mechanism and therapeutic potential

BACKGROUND: In cancer cells, telomerase induction helps maintain telomere length and thereby bypasses senescence and provides enhanced replicative potential. Chemical inhibitors of telomerase have been shown to reactivate telomere shortening and cause replicative senescence and apoptotic cell death of tumor cells while having little or no effect on normal diploid cells. RESULTS: We designed siRNAs against two different regions of telomerase gene and evaluated their effect on telomere length, proliferative potential, and gene expression in Barrett's adenocarcinoma SEG-1 cells. The mixture of siRNAs in nanomolar concentrations caused a loss of telomerase activity that appeared as early as day 1 and was essentially complete at day 3. Inhibition of telomerase activity was associated with marked reduction in median telomere length and complete loss of detectable telomeres in more than 50% of the treated cells. Telomere loss caused senescence in 40% and apoptosis in 86% of the treated cells. These responses appeared to be associated with activation of DNA sensor HR23B and subsequent activation of p53 homolog p73 and p63 and E2F1. Changes in these gene regulators were probably the source of observed up-regulation of cell cycle inhibitors, p16 and GADD45. Elevated transcript levels of FasL, Fas and caspase 8 that activate death receptors and CARD 9 that interacts with Bcl10 and NFKB to enhance mitochondrial translocation and activation of caspase 9 were also observed. CONCLUSION: These studies show that telomerase siRNAs can cause effective suppression of telomerase and telomere shortening leading to both cell cycle arrest and apoptosis via mechanisms that include up-regulation of several genes involved in cell cycle arrest and apoptosis. Telomerase siRNAs may therefore be strong candidates for highly selective therapy for chemoprevention and treatment of Barrett's adenocarcinoma

The shaping and functional consequences of the dosage effect landscape in multiple myeloma

Background: Multiple myeloma (MM) is a malignant proliferation of plasma B cells. Based on recurrent aneuploidy such as copy number alterations (CNAs), myeloma is divided into two subtypes with different CNA patterns and patient survival outcomes. How aneuploidy events arise, and whether they contribute to cancer cell evolution are actively studied. The large amount of transcriptomic changes resultant of CNAs (dosage effect) pose big challenges for identifying functional consequences of CNAs in myeloma in terms of specific driver genes and pathways. In this study, we hypothesize that gene-wise dosage effect varies as a result from complex regulatory networks that translate the impact of CNAs to gene expression, and studying this variation can provide insights into functional effects of CNAs. Results: We propose gene-wise dosage effect score and genome-wide karyotype plot as tools to measure and visualize concordant copy number and expression changes across cancer samples. We find that dosage effect in myeloma is widespread yet variable, and it is correlated with gene expression level and CNA frequencies in different chromosomes. Our analysis suggests that despite the enrichment of differentially expressed genes between hyperdiploid MM and non-hyperdiploid MM in the trisomy chromosomes, the chromosomal proportion of dosage sensitive genes is higher in the non-trisomy chromosomes. Dosage-sensitive genes are enriched by genes with protein translation and localization functions, and dosage resistant genes are enriched by apoptosis genes. These results point to future studies on differential dosage sensitivity and resistance of pro- and anti-proliferation pathways and their variation across patients as therapeutic targets and prognosis markers. Conclusions: Our findings support the hypothesis that recurrent CNAs in myeloma are selected by their functional consequences. The novel dosage effect score defined in this work will facilitate integration of copy number and expression data for identifying driver genes in cancer genomics studies. The accompanying R code is available at http://www.canevolve.org/dosageEffect/

The Treatment of Multiple Myeloma Patients Not Eligible for Asct

Advances in therapies for younger patients with multiple myeloma have resulted in significant improvements in outcome over recent years, on the contrary the progress in treatments for elderly patients has remained more modest. Traditionally, patients who are not eligible for transplantation, like the older patients, have been treated with the combination of melphalan plus prednisone (MP), which leads to responses in approximately 50% of patients; however, patients rarely achieve a complete response (CR) and long-term outcomes are disappointing, with a relapse-free survival of approximately 18 months and an overall survival (OS) of approximately 3 years