Additional Autoimmune Diseases Research Articles

Associated Autoimmune Diseases in Systemic Sclerosis Define a Subset of Patients with Milder Disease: Results from 2 Large Cohorts of European Caucasian Patients

To assess the prevalence and potential associations with the systemic sclerosis (SSc) phenotype of additional autoimmune diseases (AID). A multicenter study was performed in France and Italy to recruit consecutive European Caucasian patients with SSc systematically assessed for the coexistence of predefined AID known to occur with connective tissue diseases. We recruited 585 French and 547 Italian patients with SSc. Specific AID were found in 114/585 (19%) French and 179/547 (33%) Italians with SSc (p < 0.0001). Sjögren's syndrome and thyroiditis were the predominant AID in both cohorts (12% for Sjögren's syndrome and 6% for thyroiditis in the combined populations). The frequency of myositis, primary biliary cirrhosis, rheumatoid arthritis, and systemic lupus erythematosus was low (< 4%) and similar in both cohorts. The coexistence of at least 1 of the AID in the whole cohort was associated in multivariate analysis with the limited cutaneous subtype, the presence of antinuclear antibodies, and a lower prevalence of digital ulcers. Our study shows that 21% of this large series of European Caucasian patients with SSc have developed at least 1 AID. This latter condition identified a subset of patients with milder disease. Thus, associations of AID and autoimmune background in SSc have to be considered for further therapeutic and biological investigations in SSc.

Lymphocyte imbalance in vitiligo patients indicated by elevated CD4+/CD8+ T-cell ratio

Vitiligo is a disorder of pigmentation associated with an autoimmune-mediated loss of melanocytes from the epidermis. Humoral immunity and the involvement of cellular immunity have been investigated in the pathogenesis of vitiligo. We evaluated the role of pro-inflammatory cytokines and lymphocyte fractions in peripheral blood in a cohort of Austrian patients with vitiligo. Morning blood samples from 40 patients with vitiligo were collected. Twenty-one patients had active and 19 had stable vitiligo disease. All patients were suffering from non-segmental vitiligo at different stages of the disease. Sixteen persons presented with an additional autoimmune thyroid disease. To evaluate a possible involvement of proinflammatory cytokines in vitiligo we measured sTNF-RI (soluble tumour necrosis factor receptor I), IL-6 and additionally CIC (circulating immune complexes). We compared these findings to the data from matched normal persons. To investigate the mechanisms of cellular immunity, peripheral blood cell count and lymphocyte subtype analysis by flow cytometry were done. sTNF-RI, IL-6 and CIC serum levels were in the normal range. In the patient group median sTNF-RI level was 1.5 ng/ml and median CIC level was 35.2 microg/ml, and no statistically significant differences to the control group were observed. Median IL-6 level in vitiligo patients was 2.7 pg/ml and in the normal range-but higher than the median level of 0.5 pg/ml observed in normal persons (p < 0.001). Absolute and relative counts of lymphocyte subtypes were normal. The ratio of CD4+/CD8+ T-cells had an elevated median value of 2.6 [quartiles 2.0; 3.1]. 61% of the vitiligo patients had a ratio higher than 2.4, which was the normal cut-off point. In most vitiligo patients the balance of cytotoxic/suppressor and helper/inducer T-cells in peripheral blood is disturbed which might lead to a predominance of T-cell subtypes in the intracutaneous site of autoimmune melanocyte loss.

Expression of complement C3b/C4b receptors (CR1) on erythrocytes from patients with myasthenia gravis

The complement C3b/C4b receptor (CR1) expression on erythrocytes (E) (ECR1) from patients with myasthenia gravis (MG) and from blood donors was measured using haemadsorption and indirect hemagglutination techniques. The ECR1 expression in patients with MG appeared to be normal. This was also true for the subgroup of MG patients with additional autoimmune diseases. No correlation between ECR1 expression and severity of myasthenic symptoms was demonstrated.

High rates of complications and substantial mortality in both types of refractory sprue

Refractory sprue (RS) is a rare malabsorption syndrome defined by persisting small bowel villous atrophy despite a strict gluten-free diet. The clinical picture and long-term outcome of RS is highly variable and is not well described. To define underlying and accompanying diseases and clinical outcome in consecutive patients with RS. Clinical and histological data from patients with RS at our department were analyzed retrospectively. RS was defined as villous atrophy and malabsorption despite a strict gluten-free diet persisting without improvement for more than 6 months or requiring earlier therapeutic intervention. Thirty-two patients with RS were identified (23 RS type I, nine RS type II). Follow-up period was 55 (12-372) months. Two patients progressed from RS type I into type II. Thrombembolic events occurred in nine cases, and additional autoimmune diseases were found in 17 patients. Overt intestinal T-cell lymphoma developed in four patients with RS type II. Three patients with RS type II died during the observation period owing to intestinal T-cell lymphoma and four with RS type I owing to infectious complications. Five-year cumulative survival was 90% (95% confidence interval 76-100) in patients with RS type I and higher than in patients with RS type II (53%, 12-94%; P<0.05). RS comprises a very heterogenous group of patients with long-term survival seen even in single patients with RS type II. Overall, survival is shorter in RS type II in comparison with RS type I. Patients with RS type I, however, show similar rates of disease-related complications as well as substantial mortality.

Bilateral Anterior Granulomatous Keratouveitis with Sunset Glow Fundus in a Patient with Autoimmune Polyglandular Syndrome

Aim: To report the case of a patient with bilateral anterior granulomatous keratouveitis and sunset glow fundus. Method: Review of case record. Results: A 15-year-old patient had bilateral anterior granulomatous keratouveitis and sunset glow fundus similar to findings in Vogt-Koyanagi-Harada disease (VKH). However, the patient also suffered additional autoimmune disease against endocrine glands. In addition to anti-thyroid antibody and anti-glutamic acid decarboxylase antibody, anti-melanocyte autoantibody was detected in serum from this patient. The authors finally diagnosed autoimmune polyglandular syndrome. Conclusion: If resistance against treatment exists for VKH, particularly in pediatric cases, this disease should be considered and other endocrine disorders examined.

Complement Abnormalities in Acquired Lipodystrophy Revisited

Lipodystrophy is a heterogeneous condition characterized by an inherited or acquired deficiency in the number of adipocytes required for the storage of energy as triglycerides. Acquired lipodystrophy is frequently associated with other autoimmune disorders. One well-studied form is characterized by the selective loss of upper body fat in association with activation of the alternative complement pathway by C3 nephritic factor, low complement factor C3, and mesangiocapillary glomerulonephritis. We now describe an immunologically distinct form of acquired generalized lipodystrophy, with evidence of activation of the classical complement pathway (low C4) and autoimmune hepatitis. Patients and Research Design: Three unrelated patients with acquired lipodystrophy and low complement C4 levels are described. In vitro analysis of the complement pathway was undertaken to determine the reason for the low C4 complement levels. Biopsies were obtained from liver, bone marrow, and adipose tissue for histological analysis. All three patients manifested near-total lipodystrophy, chronic hepatitis with autoimmune features, and low C4 complement levels. Additional autoimmune diseases, including severe hemolytic anemia, autoimmune thyroid disease, and polyneuropathy, were variably present. Detailed studies of complement pathways suggested constitutive classical pathway activation. Although the previously described syndrome, which typically results in a cephalad pattern of partial lipodystrophy, results from activation of the alternative complement pathway, this form, in which lipodystrophy is generalized, is associated with activation of the classical pathway. Future therapeutic approaches to these disorders may benefit from being tailored to their distinct immunopathogenesis.

Prevalence of autoimmune thyroid disease and thyroid dysfunction in young Brazilian patients with type 1 diabetes

Patients with an autoimmune condition are known to be at higher risk of developing other autoimmune disorders. Type 1 diabetes may be associated with additional autoimmune disorders including autoimmune thyroid disease. The aim of this study was to investigate the prevalence of thyroid autoantibodies in a group of children, adolescents, and young adults with type 1 diabetes from northeastern Brazil as well as their significance for the development of thyroid disorders. The study design was cross-sectional and descriptive, analyzing young people with a previous type 1 diabetes diagnosis. Two hundred and fourteen children and adolescents with prior diagnosis of type 1 diabetes were evaluated. Antibodies to thyroperoxidase (anti-TPO) were determined in all patients and thyroid-stimulating hormone (TSH) levels. The anti-TPO antibody test was positive in 54 out of the 214 patients studied, resulting in an overall prevalence of 25.2%. Among the anti-TPO-positive subjects, females were predominant (72%) over males (28%) (p < 0.001). A total of 55.5% patients with positive anti-TPO antibodies had abnormal TSH levels. Clinically significant hypothyroidism was found in 29.6% and subclinical hypothyroidism in 22.2% of patients with positive anti-TPO. Hyperthyroidism was present in only 3% of them. Our results demonstrate the high prevalence of autoimmune thyroiditis in patients with type 1 diabetes and the need for these patients of regular screening to make a precocious diagnosis of thyroid dysfunction.

The Frequency of Rheumatic Disease Autoantibodies in Patients with ADAMTS13-Deficient Thrombotic Thrombocytopenia Purpura (TTP).

Patients who have TTP associated with acquired, severe ADAMTS13 deficiency have an autoimmune etiology and therefore may have increased risk for additional autoimmune disorders. The Oklahoma TTP-HUS Registry enrolled 247 consecutive patients with their first episode of clinically diagnosed TTP from 11-13-1995 (the date of our initial ADAMTS13 measurement) to 6-30-2006 for whom plasma exchange treatment was requested; ADAMTS13 activity was measured in 228 (92%) of patients immediately before their first plasma exchange treatment; 42 (18%) patients had ADAMTS13 activity <10%. Three patients were excluded from this analysis because of preexisting systemic rheumatic disease (systemic lupus erythematosus (SLE), 2, Sjogren's syndrome, 1). To examine the potential risk for development of autoimmune disorders, we measured screening autoantibodies (ANA, dsDNA, Sm, nRNP, Ro, La, ribosomal P, Jo-1, anti-phospholipid (aPL) IgG and IgM) in 34 of the 39 (87%) remaining patients. The median age at initial presentation was 39 years (range 9–71 years); 27 (79%) patients were women; 13 (41%) patients were black. Autoantibodies were measured by indirect immunofluorescence, immunodiffusion, or ELISA. Measurements were performed only once in 16 patients; in 18 patients 2–3 measures were performed over a period of 13 to 126 months.Rheumatic disease autoantibodiesTTP patientsANA ≥1:40 on at least one occasion33/34 (97%)ANA ≥1:120 on at least one occasion29/34 (85%)ANA measured ≥2 times, increasing titer14/16* (88%)Anti-dsDNA ≥1:3012/34 (35%)Anti-Ro positive14/29 (48%)Anti-Sm positive1/34 (3%)Anti-nRNP positive1/34 (3%)aPL IgG and/or IgM ≥moderate positive4/34 (12%)*1 patient had a maximum titer of >1:3240 in 2 samples; 1 patient developed overt SLE and his titer decreased with treatment.No patients had positive tests for anti-La, anti-Ribo-P, or anti-Jo-1. 23 (68%) of the 34 patients had a positive test for one or more rheumatic disease autoantibodies (dsDNA, nRNP, Ro, La, or moderately positive aPLs). 4 of the 34 patients died during their initial episode; the remaining 30 patients have been followed for a median of 6.4 years (range, 1–11.5 years). During this time only 1 patient has developed clinically evident SLE; no other patients have developed systemic rheumatic diseases.Conclusions:1.A high prevalence of rheumatic disease-associated autoantibodies were found in a cohort of consecutive patients with TTP associated with acquired severe ADAMTS13 deficiency.2.The presence of dsDNA and Ro autoantibodies and increasing ANA titers suggest that patients with ADAMTS13-deficientTTP may have a potential risk for developing additional autoimmune disorders such as SLE or Sjogren's syndromes.3.[3] These serologic observations support clinical observations that presenting features of TTP and SLE may overlap.

Coexistence of systemic sclerosis with other autoimmune diseases

To evaluate the coexistence of additional autoimmune disease in a population of patients suffering from systemic sclerosis. The record-charts of 118 Italian patients affected by systemic sclerosis (12 men, 106 women, mean age of 57.2 years, mean duration of disease 8.7 years) followed by a single centre were reviewed; any other diagnose of autoimmune disease the patient was given was recorded. Thirty-eight scleroderma patients (32.2%) were affected by one or two concomitant autoimmune diseases, for a total of 42 diagnoses. The most represented associated autoimmune diseases were autoimmune thyroiditis (17 cases) and primary Sjögren's syndrome (10 cases). Both pulmonary fibrosis as diagnosed by chest X-ray and the extension of skin involvement evaluated by Rodnan total skin score were not correlated with an increased incidence of an additional autoimmune disorder. Our study shows that approximately one third of patients affected by systemic sclerosis developed one or more additional autoimmune diseases. Therefore patients with systemic sclerosis should be carefully evaluated both at onset and during the follow-up for the possible coexistence of other autoimmune disorders.

Younger Age at Onset of Type 1 Diabetes in Concordant Sibling Pairs Is Associated With Increased Risk for Autoimmune Thyroid Disease

Individuals with type 1 diabetes are at increased risk for the development of additional autoimmune disorders compared with the general population (1–11). Autoimmune thyroiditis (AIT) and celiac disease are relatively common among patients with type 1 diabetes, with prevalence rates of ∼17 and 6%, respectively (4). We sought to examine the relationship between age at onset of type 1 diabetes and prevalence of additional autoimmune disorders in a sample of sibling pairs concordant for type 1 diabetes. Sibling pairs concordant for type 1 diabetes who visited the Joslin Diabetes Center’s Pediatric, Adolescent, and Young Adult Section between June 2002 and March 2005 were identified via a search of the electronic patient database. All identified patients were insulin dependent since diagnosis and showed no evidence of insulin resistance. Monozygotic twin pairs were excluded from the study. Charts were analyzed for evidence of additional autoimmune disorders. The institutional review board approved the study protocol. Sibling pairs were classified according to age at type 1 diabetes diagnosis. Group 1 was composed of pairs in which both proband and sibling were diagnosed at <10 years of age. Group 2 was composed of all other pairs (i.e., at least one sibling diagnosed at 10–18 years). Screening for thyroid dysfunction was performed by obtaining thyroxine (T4 and T3RU) and/or serum thyrotropin (TSH). At least one screening was performed every 2 years in 90% of the patients. Screening for celiac disease was obtained on any patient with symptoms …

Vitiligo patients present lower plasma levels of α-melanotropin immunoreactivities

Vitiligo is a depigmenting disorder characterized by the development of white patches with evidence in favour of an autoimmune mechanism. We investigated the role of melanotropins and the plasma levels of alpha-melanotropin and ACTH-like immunoreactivities in 40 vitiligo patients with the aim of detecting a possible influence of neuropeptide regulation of immunity. Twenty-one patients had active and 19 had stable vitiligo disease, 16 persons presented with an additional autoimmune thyroid disease. Median alpha-MSH levels in vitiligo patients were 6.4p mol/l [5.2;11.3] and significantly lower than in control persons with 11.4 pmol/l [8.6;13.4]. Median ACTH levels of the affected patient group were 17 pg/ml [10.5;28] and appeared statistically higher than 12 pg/ml [7;17] measured in the control group. Measured morning cortisol levels in both groups were not significantly different. Reduced cutaneous alpha-MSH immunoreactivities have been related to the development of autoimmune-induced depigmenting disorders. Our data present lower alpha-MSH plasma levels in vitiligo patients which may be associated with the development of vitiligo depigmentation and may indicate a condition of impaired peripheral tolerance in this autoimmune disorder.

A general autoimmunity gene (PTPN22) is not associated with inflammatory bowel disease in a British population

A single-nucleotide polymorphism (C1858T) causing an amino acid substitution (R620W) in the lymphoid protein tyrosine phosphatase gene PTPN22 has been implicated in type 1 diabetes, rheumatoid arthritis, systemic lupus erythematosus, Graves' disease, juvenile idiopathic arthritis and Hashimoto's thyroiditis, thus revealing a general role for this gene in autoimmune disease. We investigated the association of the C1858T variant in an additional autoimmune disease population by performing a case-control study of 514 British individuals with inflammatory bowel disease (IBD) [294 with Crohn's disease (CD) and 220 with ulcerative colitis (UC)] and 374 normal controls. No significant differences in genotype or allele frequencies were observed between IBD, CD or UC and controls, indicating that PTPN22 does not influence risk of IBD.

Myasthenia gravis accompanied by alopecia areata: clinical and immunogenetic aspects

The purpose of this study was to evaluate the clinical characteristics of patients who had both myasthenia gravis (MG) and alopecia areata (AA). Clinical information was retrospectively collected for 159 Japanese patients with MG. Human leukocyte antigen (HLA)-DQB1 and DRB1 alleles were determined by genotyping. Of 159 MG patients, six (3.7%) developed AA after the onset of MG and thymectomy. The prevalence of AA in MG patients was higher than that reported in Caucasians. The frequencies of bulbar involvement, myasthenic crisis, and thymoma were significantly higher in MG patients with AA than in those without (P = 0.007, 0.004, and 0.006, respectively). All but one patient with AA had advanced stage thymoma. Three patients with a severe form of AA (alopecia totalis) had additional autoimmune diseases: myocarditis, myositis, and pure red cell aplasia. DRB1*0901 and DQB1*0303 tended to be more frequently detected in the six MG patients with AA than in the 82 patients without it. In conclusion, a subset of MG patients who have severe neuromuscular symptoms and thymoma develop AA several years after thymectomy.

Polyendocrine autoimmunity

Autoimmune polyendocrine disorders are characterized by the presence of more than one autoimmune endocrine disease. Study of such disorders has provided unique insight into the pathogenesis of autoimmunity and the development of tolerance in the normal individual. Autoimmune polyendocrine syndromes I and II have distinctive inheritance patterns, genetic causes, component diseases, and implications for follow-up. Care for individuals with these diseases requires monitoring for additional autoimmune disorders and aggressive treatment of identified diseases to prevent morbidity and mortality in affected individuals.

Narrative Review: Celiac Disease: Understanding a Complex Autoimmune Disorder

Celiac disease is a common autoimmune disorder that has genetic, environmental, and immunologic components. It is characterized by an immune response to ingested wheat gluten and related proteins of rye and barley that leads to inflammation, villous atrophy, and crypt hyperplasia in the intestine. The disease is closely associated with genes that code for human leukocyte antigens DQ2 and DQ8. Transglutaminase 2 appears to be an important component of the disease, both as a deamidating enzyme that can enhance the immunostimulatory effect of gluten and as a target autoantigen in the immune response. Sensitive and specific serologic tests, including those for anti-transglutaminase antibody, are facilitating fast and noninvasive screening for celiac disease. Thus, they are contributing to a more accurate estimate of the prevalence of the disease and its association with other disorders. Celiac disease is associated with increased rates of anemia, osteoporosis, cancer, neurologic deficits, and additional autoimmune disorders. A gluten-free diet is the mainstay of safe and effective treatment of celiac disease, although its effect on some of the extraintestinal manifestations of the disease remains to be determined.

Associated autoimmune diseases in patients with the Lambert-Eaton myasthenic syndrome and their families

In view of the clustering of autoimmune diseases (AIDs), we studied the frequency and nature of additional AIDs in patients with the Lambert-Eaton myasthenic syndrome (LEMS) and their family members, in both small cell lung carcinoma (SCLC) related and non-tumour (NT) related cases. Additional AIDs in patients with LEMS were assessed by interviewing the patient and studying the medical record. Family histories up to second-degree family members were established by interviewing patients, controls and family members. Forty-four patients with LEMS were assessed, of whom eighteen (41%) had SCLC. In the NT group seven patients (27%) had an additional AID, in the SCLC group two (11 %) (p=0.20). Thyroid disorder (five patients) and insulin dependent diabetes mellitus (two patients) were the most common AIDs. AIDs were significantly more frequent in families of patients with NT-LEMS (64%) than in control families (27%) (p=0.002), which was not found in SCLC-LEMS (36%, p=0.53). Affected family members were linked to the NT-LEMS patient through the maternal line in all cases. In conclusion, AIDs were more frequently found in LEMS patients without a tumour and their families, which could not be shown for SCLC-LEMS. This suggests that NT-LEMS shares immunogenetic factors with other AIDs. In families of NT-LEMS, a remarkable preponderance of maternal inheritance was seen, as has been reported previously in myasthenia gravis.

Patterns of autoimmunity in primary biliary cirrhosis patients and their families: a population-based cohort study.

Primary biliary cirrhosis (PBC) is a chronic liver disease with autoimmune features but uncertain aetiology. Increased risk of PBC among relatives of patients may reflect common environmental factors, or inherited immunogenetic susceptibility. Associations between PBC and other autoimmune diseases have been reported, but their true extent and pattern is unknown. To examine the prevalence and association patterns of autoimmune disease in a representative group of PBC patients. Clinical cohort study. We clinically assessed members of a geographically-based PBC patient cohort (n = 160) for the presence of additional autoimmune disease, using established specific diagnostic criteria. Some 53% of patients had at least one additional autoimmune condition, and 63% had serum autoantibodies other than AMA or ANA. AMA+ patients had a significantly lower prevalence of additional autoimmunity than AMA- patients (49% vs. 79%; p < 0.01). The greatest relative increase in disease prevalence was for scleroderma (8% of patients). Autoimmune disease was present in 14% of first-degree relatives. PBC patients and their families have a wide susceptibility to autoimmunity. This observation supports an autoimmune aetiology and suggests that the genetic basis of PBC is likely to be expressed, at least in part, through factors controlling immune tolerance in general.

Immunomodulation by the copolymer glatiramer acetate.

Glatiramer acetate (GA; Copaxone, also known as Copolymer 1 or Cop-1), a copolymer of amino acids, is very effective in the suppression of experimental autoimmune encephalitis (EAE), the animal model for multiple sclerosis (MS), in various species including primates. The immunological cross-reaction between the myelin basic protein and GA serves as the basis for the suppressive activity of GA in EAE, by the induction of antigen-specific suppressor cells. The mode of action of GA is by initial strong promiscuous binding to major histocompatibility complex class II molecules and competition with MBP and other myelin proteins for such binding and presentation to T cells. Suppressor T cells induced by GA are of the Th2 type, migrate to the brain and lead to in situ bystander suppression. Clinical trials with GA, both phase II and phase III, were performed in relapsing-remitting MS (RRMS) patients, and demonstrated efficacy in reducing the relapse rate, decreasing MRI-assessed disease activity and burden and slowing progression of disability. GA is generally well tolerated and is not associated with influenza-like symptoms and formation of neutralizing antibodies seen with beta-interferons. It exerts its suppressive effect primarily by immunomodulation, and has recently shown ameliorating effect in a few additional autoimmune disorders as well as in graft rejection. At present GA is considered a valuable first-line treatment option for patients with RRMS.

Autoimmune diseases in vitiligo: do anti-nuclear antibodies decrease thyroid volume?

An increased prevalence of autoimmune thyroiditis (AT) in vitiligo patients is well known. The aim of this study was firstly, to evaluate the clinical course of patients with both vitiligo and AT and secondly, to identify additional autoimmune disorders affecting the thyroid gland in a large cohort of vitiligo patients. We analysed a study group of 106 vitiligo patients and 38 controls. A detailed thyroid examination including sonography was performed in all study participants. In addition, the study participants were HLA typed and screened for various autoimmune disorders. AT was significantly more frequent in vitiligo patients than in controls (21%versus 3%; P < 0.01). In 12 of the 22 patients with AT, vitiligo was the initial disease preceding AT by 4-35 years. In the other 10 patients with AT, both vitiligo and AT were diagnosed within one year. There were two individuals with diabetes mellitus type 1 and a single patient with Addison's disease. Anti-nuclear antibody (ANA), anti-smooth muscle cell antibody, and parietal cell antibody levels occurred with a similar frequency in patients and controls. In all vitiligo patients with both elevated ANA levels and AT (n = 6), the atrophic but not the goitrous variant was diagnosed. These vitiligo patients with both AT and elevated ANA levels had a significantly smaller thyroid volume compared to the vitiligo patients with AT whose ANA levels were normal (6.7 +/- 4.5 ml versus 13.4 +/- 9.1 ml, respectively; P < 0.05). The same was found in the entire study group: Thyroid volume of all vitiligo patients (with or without concomitant AT) was significantly smaller in the presence of ANA (6.9 +/- 5.3 versus 10.5 +/- 5.9 ml, respectively; P < 0.05). However, this phenomenon was not observed in the control group. There was a trend for a decreased frequency of HLA-DR3 (6.7%versus 23%) in our study group, but after correction for the number of comparisons, no HLA-allele was statistically significant associated neither with vitiligo nor with multiple autoimmune diseases in our patient sample. Our findings suggest that AT is the most frequent autoimmune disease associated with vitiligo. In our patients, AT presented simultaneously or after the onset of vitiligo but not before. Elevated ANA levels were associated with the atrophic variant of AT and may affect the volume of the thyroid gland, and there was no statistically significant association with the HLA system.

Biological Activities, Mechanisms of Action and Biomedical Prospect of the Antitumor Ether Phospholipid ET-18-OCH3 (Edelfosine), A Proapoptotic Agent in Tumor Cells

The antitumor ether lipid ET-18-OCH(3) (edelfosine) is the prototype of a new class of antineoplastic agents, synthetic analogues of lysophosphatidylcholine, that shows a high metabolic stability, does not interact with DNA and shows a selective apoptotic response in tumor cells, sparing normal cells. Unlike currently used antitumor drugs, ET-18-OCH(3) does not act directly on the formation and function of the replication machinery, and thereby its effects are independent of the proliferative state of target cells. Because of its capacity to modulate cellular regulatory and signaling events, including those failing in cancer cells, like defective apoptosis, ET-18-OCH(3), beyond its putative clinical importance, is an interesting model compound for the development of more selective drugs for cancer therapy. Although ET-18-OCH(3) enhances host defense mechanisms against tumors, its major antitumor action lies in a direct effect on cancer cells, inhibiting phosphatidylcholine biosynthesis and inducing apoptosis in tumor cells. Recent progress has allowed unraveling the molecular mechanism underlying the apoptotic action of ET-18-OCH(3), leading to the notion that ET-18-OCH(3) is selectively incorporated into tumor cells and induces cell death by intracellular activation of the cell death receptor Fas/CD95. This intracellular Fas/CD95 activation is a novel mechanism of action for an antitumor drug and represents a new way to target tumor cells in cancer chemotherapy that can be of interest as a new framework in designing novel antitumor drugs. ET-18-OCH(3) and some analogues are pleiotropic agents that affect additional biomedical important diseases, including parasitic and autoimmune diseases, suggesting new therapeutic indications for these compounds.