Tuesday, 22 August 2017

A bygone era: AZA, MTX, CYC increase cancer risk in MS

BMC Neurol. 2017 Aug 8;17(1):155. doi: 10.1186/s12883-017-0932-0.

Association between multiple sclerosis, cancer risk, and immunosuppressant treatment: a cohort study.

Ragonese P, Aridon P, Vazzoler G, Mazzola MA, Lo Re V, Lo Re M, Realmuto S, Alessi S, D'Amelio M, Savettieri G, Salemi G.



The association between multiple sclerosis (MS) and cancer has long been investigated with conflicting results. Several reports suggest an increased cancer risk among MS patients treated with immunosuppressant (IS) drugs.


We performed a cohort study including MS patients recruited at the Neurological Department of the University of Palermo. Mean follow-up period was ten years for the whole cohort. We calculated cancer incidence among patients treated with IS. Incidence rates were compared in the cohort by calculating the relative risk according to length and dose of exposure to IS. Cancer incidence among MS patients was compared to cancer incidence in the general population of Sicily in similar age groups.


On an overall cohort of 531 MS patients (346 women and 185 men) exposed to IS, we estimated a crude incidence rate for cancer of 2.26% (2.02% in women, 2.7% in men). Cancer risk was higher compared to rates observed among an equal number of patients not exposed to IS, and to the risk in the general population in Sicily at similar age groups (adjusted HR: 11.05; CI 1.67-73.3; p = 0.013).


The present study showed a higher cancer risk in MS patients associated only to previous IS exposure. Studies on long-term outcomes are essential to evaluate the possibility that treatment options that need to be considered for a long time-period may modify risk for life threatening diseases.

The association between MS therapies and cancer risk is neither simple nor clear cut. However, context is all, and cancer is undoubtedly the single most important thing in a person's life - not too banal to be buried under some statistic or to exercise tolerance over...And yet our understanding of it has not improved. A work in progress.

Here, Ragonese et al., report that simply having MS does not increase your cancer risk. Although, other epidemiological research have alluded to a link based on the type of cancer. The authors, however did note an increase cancer risk in those who took the older immunosuppressant drugs - azathioprine (AZA), mitoxantrone (MTX) and cyclophosphamide (CYC); compared to age-adjusted controls (hazard ratio 11.05; 95% CI 1.67-73.3). This risk appears to be largely driven by AZA and MTX, rather than CYC where no cancers were observed (although the group receiving CYC was small and the follow up was not as long as for the other drugs). The average treatment period was 5y for AZA and 1y for MTX, but this alone led to a 4-fold increase in cancer. With MTX, the association was with leukaemia, which is a known risk of the drug. We no longer use AZA/MTX in MS, but continue to do so in neuromyelitis optica, sarcoidosis, for example, and as such should be more cautious over their long-term use. Improved surveillance programmes may be the answer.

Unfortunatly, this work does not look at the newer agents (Copaxone, Interferons, and monoclonal antibody therapies). Again, the data on this from other studies are conflicting, and it's not certain whether these drugs are exposing an intrinsic cancer susceptibility in MS.

In summary, cancer risk from immunosuppressant use is a realistic one. It is a debate worth having. Make it your agenda for this year and the next.

Monday, 21 August 2017

In Top 50 MS blogs

Got Email to say we are in top 50 MS blogs.....Ta.....However no links to their website even from the picture..So you'll have to guess who ;-)

Gene expression is controlled in MS the effect of Carbon and hydrogen

Pinto-Medel MJ, Oliver-Martos B, Urbaneja-Romero P, Hurtado-Guerrero I, Ortega-Pinazo J, Serrano-Castro P, Fernández Ó, Leyva L.Global methylation correlates with clinical status in multiple sclerosis patients in the first year of IFNbeta treatment.
Sci Rep. 2017;7(1):8727.

The alteration of DNA methylation patterns are a key component of disease onset and/or progression. Our objective was to evaluate the differences in Long Interspersed Nuclear Element-1 (LINE-1) methylation levels, as a surrogate marker of global DNA methylation, between multiple sclerosis (MS) patients and healthy controls. In addition, we assessed the association of LINE-1 methylation with clinical disease activity in patients treated with IFNbeta (IFNβ). We found that individuals with high levels of LINE-1 methylation showed 6-fold increased risk of suffering MS. Additionally, treated MS patients who bear high LINE-1 methylation levels had an 11-fold increased risk of clinical activity. Moreover, a negative correlation between treatment duration and percentage of LINE-1 methylation, that was statistically significant exclusively in the group of patients without clinical activity, was observed. Our data suggest that in MS patients, a slight global DNA hypermethylation occurs that may be related to the pathophysiology of the disease. In addition, global DNA methylation levels could play a role as a biomarker for the differential clinical response to IFNβ.

So in this study it implicates hypermethylation as a problemChomyk AM, Volsko C, Tripathi A, Deckard SA, Trapp BD, Fox RJ, Dutta R.DNA methylation in demyelinated multiple sclerosis hippocampus.Sci Rep. 2017 ;7(1):8696

Multiple Sclerosis (MS) is an immune-mediated demyelinating disease of the human central nervous system (CNS). Memory impairments and hippocampal demyelination are common features in MS patients. Our previous data have shown that demyelination alters neuronal gene expression in the hippocampus. DNA methylation is a common epigenetic modifier of gene expression. In this study, we investigated whether DNA methylation is altered in MS hippocampus following demyelination. Our results show that mRNA levels of DNA methyltransferase were increased in demyelinated MS hippocampus, while de-methylation enzymes were decreased. Comparative methylation profiling identify hypo-methylation within upstream sequences of 6 genes and hyper-methylation of 10 genes in demyelinated MS hippocampus. Genes identified in the current study were also validated in an independent microarray dataset generated from MS hippocampus. Independent validation using RT-PCR revealed that DNA methylation inversely correlated with mRNA levels of the candidate genes. Queries across cell-specific databases revealed that a majority of the candidate genes are expressed by astrocytes and neurons in mouse and human CNS. Taken together, our results expands the list of genes previously identified in MS hippocampus and establish DNA methylation as a mechanism of altered gene expression in MS hippocampus.

In this study some genes are methylated others are not

Methylation is the addition of a methyl group which is one carbon atom and three hydrogen atoms

DNA contains combinations of four nucleotides which include cytosine, guanine, thymine and adenine. DNA methylation refers to the addition of a methyl (CH3) group to the DNA strand itself, often to the fifth carbon atom of a cytosine ring. This conversion of cytosine bases to 5-methylcytosine is catalysed by DNA methyltransferases (DNMTs). These modified cytosine residues usually lie next to a guanine base (CpG methylation) and the result is two methylated cytosines positioned diagonally to each other on opposite strands of DNA.

Different DNMTs work together either as nw DNMTs, establishing the methyl group pattern on a sequence of DNA or as maintenance DNMTs that copy the methylation pattern on an existing strand of DNA to its new partner following replication. Methylation is sparse but global in mammals, found in CpG sequences across the entire genome, aside from certain stretches (of around one kilobase) where the content of CpG is high (CpG islands). When those sequences are methylated, the result can be silencing of gene.
This also enables the expression of retroviral genes to be suppressed, 

What does it all mean, i don't know at present but this is a way that gene function can be altered.

Sunday, 20 August 2017

Do Marmosets hold the answer to understanding the role of EBV virus

't Hart BA, Jagessar SA, Haanstra K, Verschoor E, Laman JD, Kap YS. The Primate EAE Model Points at EBV-Infected B Cells as a Preferential Therapy Target in Multiple Sclerosis. Front Immunol. 2013 Jun 13;4:145

The remarkable clinical efficacy of anti-CD20 monoclonal antibodies (mAb) in relapsing-remitting multiple sclerosis points at the critical involvement of B cells in the disease. However, the exact pathogenic contribution of B cells is poorly understood. In this publication we review new data on the role of CD20+ B cells in a unique experimental autoimmune encephalomyelitis (EAE) model in common marmosets (Callithrix jacchus), a small-bodied neotropical primate. We will also discuss the relevance of these data for MS. Different from rodent EAE models, but similar to MS, disease progression in marmosets can develop independent of autoantibodies. Progressive disease is mediated by MHC class Ib (Caja-E) restricted cytotoxic T cells, which are activated by γ-herpesvirus-infected B cells and cause widespread demyelination of cortical gray matter. B-cell directed monoclonal antibody therapies (anti-CD20 versus anti-BLyS and anti-APRIL) have a variable effect on EAE progression, which we found associated with variable depletion of the Epstein Barr virus (EBV)-like γ-herpesvirus CalHV3 from lymphoid organs. These findings support an important pathogenic role of CD20+ B cell in MS, especially of the subset infected with EBV.

MS is a uniquely human disease, but we have been modeling it in animals for years. Anti-CD20 antibodies made people stop and think. We have reported that anti-CD20 and all effective agents deplete memory B cells. This could be depleting the viral reservoir of MS as EBV infects CD21 expressing B cells and this virus drives then down the memory cell lineage.

EBV is largely unique to humans but there are some non-human primates that have a similar herpes virus, one such animal is the marmoset, which I first encountered when it was being used in Burkitt's Lymphoma-related research. Indeed marmosets have their own EBV-like virus. 

What does it do in the marmosets? Is it pathogenic or is co-evolved.
Do marmosets get spontaneous MS?

I don't think they do, but  stand to be corrected, but they do get EAE.

For many, many years the TH1/Th17 CD4 brigade had ruled the roost, shaping ideas on MS pathology and treatment. However, looking at MS and the response to therapy did not support this view. Both rodent relapsing EAE and the Marmoset treated late questioned the importance of IL12/IL23, but the T cell brigade ploughed on did the trial in MS which failed. In our hands CD20 in rodents doesn't do too much, in marmosets it is much more effective  and dropped the Marmoset-EBV virus. Blocking APRIL (B cell growth factor) increased the virus but also blocked EAE, however in MS blocking APRIL, made MS worse. Was this because it made more virus or memory cells?

To date it suggested that EBV-infected B cells present antigen to T cells and CD8 drive progressive disease. Will this drive a trial of CD8 depletion?  Will this work or will it make MS worse, as Prof Pender has shown anti-viral CD8 T cells are being used to treat MS.

Dental Bacteria suppressing EAE still not the right info for microbiome transplants..Keep brushing your teeth.

Mangalam A, Shahi SK, Luckey D, Karau M, Marietta E, Luo N, Choung RS, Ju J, Sompallae R, Gibson-Corley K, Patel R, Rodriguez M, David C, Taneja V, Murray J. Human Gut-Derived Commensal Bacteria Suppress CNS Inflammatory and Demyelinating Disease. Cell Rep. 2017 Aug 8;20(6):1269-1277. doi: 10.1016/j.celrep.2017.07.031.

The human gut is colonized by a large number of microorganisms (∼100 million, million bacteria) that support various physiologic functions. A perturbation in the healthy gut microbiome might lead to the development of inflammatory diseases, such as multiple sclerosis (MS). Therefore, gut commensals might provide promising therapeutic options for treating MS and other diseases. We report the identification of human gut-derived commensal bacteria, Prevotella histicola, which can suppress experimental autoimmune encephalomyelitis (EAE) in a human leukocyte antigen (HLA) class II transgenic mouse model. P. histicola suppresses disease through the modulation of systemic immune responses. P. histicola challenge led to a decrease in pro-inflammatory Th1 and Th17 cells and an increase in the frequencies of CD4+FoxP3+ regulatory T cells, tolerogenic dendritic cells, and suppressive macrophages. Our study provides evidence that the administration of gut commensals may regulate a systemic immune response and may, therefore, have a possible role in treatment strategies for MS.

Prevotella histicola are Gram-negative bacilli that are obligately anaerobic, vary in pigmentation and are non-motile. Prevotella histicola is found in the mucosal tissues of the human oral cavity and is considered a normal flora of the human oral microbiota.

Prevotella histicola is found living in the dental plaque of the mouth. Dental plaque is simply the colonization of a microbial community on the teeth in the form of a biofilm. Dental plaque is thought to be beneficial to the host as it may aid in fighting off pathogens. It also may contribute to pathogenesis.

But before you give up getting your teeth cleans, remember this is a mouse study and the same group did a study in mouse arthritis last year and came to the same conclusion. We would need to know what this bacteria does in other species importantly in humans.