Non-invasive diagnosis of endometriosis based on a combined analysis of six plasma biomarkers.

BACKGROUND: Lack of a non-invasive diagnostic test contributes to the long delay between onset of symptoms and diagnosis of endometriosis. The aim of this study was to evaluate the combined performance of six potential plasma biomarkers in the diagnosis of endometriosis. METHODS: This case-control study was conducted in 294 infertile women, consisting of 93 women with a normal pelvis and 201 women with endometriosis. We measured plasma concentrations of interleukin (IL)-6, IL-8, tumour necrosis factor-alpha, high-sensitivity C-reactive protein (hsCRP), and cancer antigens CA-125 and CA-19-9. Analyses were done using the Kruskal-Wallis test, Mann-Whitney test, receiver operator characteristic, stepwise logistic regression and least squares support vector machines (LSSVM). RESULTS: Plasma levels of IL-6, IL-8 and CA-125 were increased in all women with endometriosis and in those with minimal-mild endometriosis, compared with controls. In women with moderate-severe endometriosis, plasma levels of IL-6, IL-8 and CA-125, but also of hsCRP, were significantly higher than in controls. Using stepwise logistic regression, moderate-severe endometriosis was diagnosed with a sensitivity of 100% (specificity 84%) and minimal-mild endometriosis was detected with a sensitivity of 87% (specificity 71%) during the secretory phase. Using LSSVM analysis, minimal-mild endometriosis was diagnosed with a sensitivity of 94% (specificity 61%) during the secretory phase and with a sensitivity of 92% (specificity 63%) during the menstrual phase. CONCLUSIONS: Advanced statistical analysis of a panel of six selected plasma biomarkers on samples obtained during the secretory phase or during menstruation allows the diagnosis of both minimal-mild and moderate-severe endometriosis with high sensitivity and clinically acceptable specificity.

Non-steroidal targets in the diagnosis and treatment of endometriosis.

Endometriosis, a chronic gynecologic disease frequently resulting in chronic pelvic pain, severe dysmenorrhoea, and subfertility, is defined as the presence of endometrial tissue at extrauterine locations, most commonly on the peritoneum and ovaries. Conclusive diagnosis requires laparoscopic surgery followed by histological confirmation. The treatment options -at present- are limited to hormonal therapies and/or surgical ablation of the lesions, and are characterized by high recurrence rates, significant side-effects and limited duration of administration. The pathogenesis of endometriosis is still unclear and numerous immunological and inflammatory factors have been suggested to be involved in the development of the disease, including interleukin (IL)-1, IL-2, IL-6, IL-8, IL-12, tumour necrosis factor -alpha (TNF-alpha), regulated on activation, normal T-Cell expressed and secreted (RANTES) and its receptor cognate chemokine receptor 1 (CCR1), peroxisome proliferator activated receptors (PPARs), matrix metalloproteinases (MMPs) and cyclooxygenase (COX). Another crucial mechanism in endometriosis is the vascularisation of the endometriotic lesions, with a key role for vascular endothelial growth factor (VEGF). Recently, protease activated receptors (PARs), mitogen-activated protein kinases (MAPKs) and tyrosine kinases have also been associated with the pathophysiology of endometriosis. The aim of this article is to discuss molecules that have recently been found to have connections with the pathogenesis of endometriosis, as potential targets to develop new methods for noninvasive diagnosis and for novel medical management of this disease. This review also critically addresses how these molecules can be tested in basic, preclinical and clinical research, the status of this research and the importance of potential side effects.

Global gene analysis of late secretory phase, eutopic endometrium does not provide the basis for a minimally invasive test of endometriosis.

BACKGROUND: Endometriosis occurs in 10% of women and is currently diagnosed by invasive laparoscopic testing. We tested the hypothesis that endometrial gene expression in late secretory phase endometrium differs between patients with and without endometriosis. METHODS: Ten patients with laparoscopically proven endometriosis (minimal/mild n = 5 and moderate/severe n = 5) and six controls, underwent endometrial biopsy in the late secretory phase (Day 23 onwards). Microarray interrogation of eutopic endometrial gene expression was performed. RESULTS: Microarray data were obtained for all control samples and eight samples from the endometriosis patients (n = 4 minimal/mild, n = 4 moderate/severe disease). Eight genes were identified as up-regulated and one gene was down-regulated in all endometriotic samples (more than 1.75-fold, P < 0.01). Real-time PCR analysis of protocadherin-17 (PCDH17), protein tyrosine phosphatase, receptor type, R (PTPRR) and interleukin-6 signal transducer (IL6ST) expression validated the microarray findings. CONCLUSIONS: Expression of very few transcripts differs, in late secretory eutopic endometrium, between controls and patients with endometriosis. The median fold changes of these genes are small. No transcripts were identified that could discriminate between minimal/mild and moderate/severe endometriosis. Therefore, interrogation of the late secretory endometrial transcriptome is not likely to form the basis of a minimally invasive diagnostic test for endometriosis.

Endometriosis, recurrent miscarriage and implantation failure: is there an immunological link?

Endometriosis is more frequently diagnosed in patients with infertility than in a normal population. The goal of this paper is to give an overview of the clinical and fundamental evidence for a possible link between endometriosis and (recurrent) miscarriage or implantation failure after treatment with assisted reproductive technology. According to the literature, there is insufficient evidence for an association between endometriosis and (recurrent) miscarriage, but there is, however, epidemiological evidence to support the link between endometriosis and recurrent implantation failure after assisted reproduction. This can possibly be explained by alterations in humoral and cell-mediated immunity in women with endometriosis. Humoral immunological changes include increased formation of antibodies against endometrial antigens, anti-laminin-1 auto-antibodies and other auto-immune antibodies (e.g. antiphospholipid). Cell-mediated immunological changes include alterations in peritoneal and follicular fluid immune cells and cytokines. The possible negative effect of these immunological changes on folliculogenesis, ovulation, oocyte quality, early embryonic development and implantation in women with endometriosis suggests that infertility in endometriosis patients may be related to alterations within the follicle or oocyte, resulting in embryos with decreased ability to implant.

Treatment with anti-TNF monoclonal antibody (c5N) reduces the extent of induced endometriosis in the baboon.

BACKGROUND: Inflammatory cytokines, including interleukin (IL)-1, IL-6, IL-8 and tumour necrosis factor-alpha (TNF-alpha), are important in the pathogenesis of endometriosis. We assessed the efficacy of anti-TNF monoclonal antibody (mAb, c5N), known to prevent induced endometriosis in baboons, in reducing established endometriosis in baboons. METHODS: This prospective, randomized, blinded, controlled study was conducted in baboons at the Institute of Primate Research (IPR), Nairobi, Kenya. Endometriosis was induced in 18 adult female baboons (Papio anubis) with regular menstrual cycles and a normal pelvis; the extent of endometriosis was documented by videolaparoscopy 25 days later. The baboons were then randomly assigned to receive a single infusion of either placebo (n=7, 5 ml/kg) or c5N (n=11, 5 mg/kg). Follow-up laparoscopy was performed 25 days later to document any differences in the number, surface area and estimated volume of lesions between the two groups and between the first and the second laparoscopies in each group. Representative biopsies of at least one endometriotic lesion per baboon were obtained at the final laparoscopy. RESULTS: Significant reductions in total surface area, estimated total volume of endometriotic lesions and both number and surface area of red lesions were observed after treatment with c5N, but not after placebo treatment, when compared to the initial laparoscopy. Conversely, a significant increase in the number of typical and red lesions was observed after placebo treatment when compared to the initial laparoscopy. Neither c5N nor placebo treatment affected the menstrual cycle. CONCLUSION: In baboons with induced endometriosis, anti-TNF-mAb (c5N) treatment significantly reduced the extent of endometriosis, mainly due to reducing both the number and surface area of red lesions. These findings suggest that anti-TNF-mAb therapy may have therapeutic potential for active peritoneal endometriosis.

Immunoglobulin repertoire of B lymphocytes infiltrating breast medullary carcinoma.

Tumor specific peptides recognized by T lymphocytes infiltrating solid tumors, as well as the corresponding T cell receptor (TcR) repertoire usage, have been extensively investigated. By contrast, tumor infiltrating B cells and their immunoglobulin (Ig) repertoire have been studied only in a limited number of tumors. The objective of the present study was to determine, whether DNA sequence analysis of the expressed immunoglobulin variable regions of B cells that infiltrate breast cancer, could be used to reveal a potential specific tumor binding capacity of the antibodies. To answer this question, about 200 expressed Ig heavy (VH) and light chain variable gene (VL) regions were cloned, sequenced and comparatively analysed from a typical medullary beast carcinoma (MBC), where the massive B and plasma cell infiltration correlates with favourable prognosis despite of its high grade. The tumor infiltrating B cell Ig heavy and light chain sequences could be classified into clusters, families and subgroups, based on the identity level to germline, showing a pattern of oligoclonality. Some overrepresented clusters could be determined. In the course of a detailed analysis and search in Blastn database, a number of VH and VL sequences showed more than 99% homology to DNA sequences of Ig VH region, with proved tumor antigen binding capacity. Our data suggest, that potential tumor binder Ig VH and VL sequences might be selected using a detailed immunoglobulin variable region analysis. This new approach might have a benefit for further antibody engineering, as difficulties in search for tumor binders by phage library selection might be reduced and the time for selection shortened.