Seby L. Edassery

Histopathology of ovarian tumors in laying hens: a preclinical model of human ovarian cancer.

The high mortality rate due to ovarian cancer (OVCA) is attributed to the lack of an effective early detection method. Because of the nonspecificity of symptoms at early stage, most of the OVCA cases are detected at late stages. This makes the access to women with early-stage disease problematic and presents a barrier to development and validation of tests for detection of early stage of OVCA in humans. Animal models are used to elucidate disease etiologies and pathogenesis that are difficult to study in humans. Laying hen is the only available animal that develops OVCA spontaneously; however, detailed information on ovarian tumor histology is not available. The goal of this study was to determine the histological features of malignant ovarian tumors in laying hens. A total of 155 young and old (1-5 years of age) laying hens (Gallus domesticus) were selected randomly and evaluated grossly and microscopically for the presence of ovarian tumors. Histological classification of tumors with their stages and grades was determined with reference to those for humans. Similar to humans, all 4 types including serous, endometrioid, mucinous, and clear cell or mixed carcinomas were observed in hen ovarian tumors. Some early neoplastic as well as putative ovarian lesions were also observed. Similarities in histology, metastasis, and stages of hen OVCA to those of humans demonstrate the feasibility of the hen model for additional delineation of the mechanism underlying ovarian carcinogenesis, preclinical testing of new agents for the prevention, and therapy of this disease.

Cotransplantation with specific populations of spina bifida bone marrow stem/progenitor cells enhances urinary bladder regeneration

Spina bifida (SB) patients afflicted with myelomeningocele typically possess a neurogenic urinary bladder and exhibit varying degrees of bladder dysfunction. Although surgical intervention in the form of enterocystoplasty is the current standard of care in which to remedy the neurogenic bladder, it is still a stop-gap measure and is associated with many complications due to the use of bowel as a source of replacement tissue. Contemporary bladder tissue engineering strategies lack the ability to reform bladder smooth muscle, vasculature, and promote peripheral nerve tissue growth when using autologous populations of cells. Within the context of this study, we demonstrate the role of two specific populations of bone marrow (BM) stem/progenitor cells used in combination with a synthetic elastomeric scaffold that provides a unique and alternative means to current bladder regeneration approaches. In vitro differentiation, gene expression, and proliferation are similar among donor mesenchymal stem cells (MSCs), whereas poly(1,8-octanediol-cocitrate) scaffolds seeded with SB BM MSCs perform analogously to control counterparts with regard to bladder smooth muscle wall formation in vivo. SB CD34+ hematopoietic stem/progenitor cells cotransplanted with donor-matched MSCs cause a dramatic increase in tissue vascularization as well as an induction of peripheral nerve growth in grafted areas compared with samples not seeded with hematopoietic stem/progenitor cells. Finally, MSC/CD34+ grafts provided the impetus for rapid urothelium regeneration. Data suggest that autologous BM stem/progenitor cells may be used as alternate, nonpathogenic cell sources for SB patient-specific bladder tissue regeneration in lieu of current enterocystoplasty procedures and have implications for other bladder regenerative therapies.

Autoantigens in ovarian autoimmunity associated with unexplained infertility and premature ovarian failure

OBJECTIVE To identify ovarian autoantigens associated with ovarian autoantibodies. DESIGN Hypothesis-generating prospective study. SETTING Urban infertility referral centers and academic research institution. PATIENT(S) Seventy-four patients with infertility, 19 patients with premature ovarian failure (POF), and 16 healthy control women. INTERVENTION(S) None. MAIN OUTCOME MEASURE(S) Identification of autoantigens. RESULT(S) To identify major antigens for ovarian autoimmunity, sera from 74 women with unexplained infertility were screened for ovarian autoantibodies (AOAs) by immunoassay and one-dimensional Western blot. The majority of sera had immunoreactions at 50-56 kDa. Six representative positive infertility sera were used to identify antigens between 40 and 60 kD by two-dimensional Western blot and mass spectrometry. Antigens included aldehyde (retinal) dehydrogenases (ALDH1A1, ALDH1A2, and ALDH7A1), protein disulfide isomerase A3, vimentin, α-enolase, phosphoglycerate dehydrogenase, and selenium-binding protein 1 (SBP1). Sixty percent (24 out of 40) of infertility and POF sera were positive for recombinant ALDH1A1, SBP1, or enolase; 80.7% (21 out of 26) of AOA-positive sera had antibodies to one or more of the three antigens, and only 7% (1 out of 14) of AOA-negative sera had antibodies to recombinant proteins. CONCLUSION(S) ALDH1A1 and SBP1 are unique to ovarian autoimmunity associated with infertility and POF, and may provide the basis for specific tests to identify patients with ovarian autoimmunity.

Differential expression of aldehyde dehydrogenase 1a1 (ALDH1) in normal ovary and serous ovarian tumors.

BackgroundWe showed there are specific ALDH1 autoantibodies in ovarian autoimmune disease and ovarian cancer, suggesting a role for ALDH1 in ovarian pathology. However, there is little information on the ovarian expression of ALDH1. Therefore, we compared ALDH1 expression in normal ovary and benign and malignant ovarian tumors to determine if ALDH1 expression is altered in ovarian cancer. Since there is also recent interest in ALDH1 as a cancer stem cell (CSC) marker, we assessed co-expression of ALDH1 with CSC markers in order to determine if ALDH1 is a potential CSC marker in ovarian cancer.MethodsmRNA and protein expression were compared in normal human ovary and serous ovarian tumors using quantitative Reverse-Transcriptase PCR, Western blot (WB) and semi-quantitative immunohistochemistry (IHC). ALDH1 enzyme activity was confirmed in primary ovarian cells by flow cytometry (FC) using ALDEFLUOR assay.ResultsALDH1 mRNA expression was significantly reduced (p < 0.01; n = 5) in malignant tumors compared to normal ovaries and benign tumors. The proportion of ALDH1+ cells was significantly lower in malignant tumors (17.1 ± 7.61%; n = 5) compared to normal ovaries (37.4 ± 5.4%; p < 0.01; n = 5) and benign tumors (31.03 ± 6.68%; p < 0.05; n = 5). ALDH1+ cells occurred in the stroma and surface epithelium in normal ovary and benign tumors, although surface epithelial expression varied more in benign tumors. Localization of ALDH1 was heterogeneous in malignant tumor cells and little ALDH1 expression occurred in poorly differentiated malignant tumors. In benign tumors the distribution of ALDH1 had features of both normal ovary and malignant tumors. ALDH1 protein expression assessed by IHC, WB and FC was positively correlated (p < 0.01). ALDH1 did not appear to be co-expressed with the CSC markers CD44, CD117 and CD133 by IHC.ConclusionsTotal ALDH1 expression is significantly reduced in malignant ovarian tumors while it is relatively unchanged in benign tumors compared to normal ovary. Thus, ALDH1 expression in the ovary does not appear to be similar to breast, lung or colon cancer suggesting possible functional differences in these cancers.SignificanceThese observations suggest that reduced ALDH1 expression is associated with malignant transformation in ovarian cancer and provides a basis for further study of the mechanism of ALDH1 in this process.

Selenium-Binding Protein 1 expression in ovaries and ovarian tumors in the laying hen, a spontaneous model of human ovarian cancer

OBJECTIVE Reduced Selenium-Binding Protein 1 (SELENBP1) expression was recently shown in multiple cancers. There is little information on the expression and function of SELENBP1 in cancer progression. In order to develop a better understanding of the role of SELENBP1 in ovarian cancer, our objective was to determine if SELENBP1 is expressed in the normal ovaries and ovarian tumors in the egg-laying hen, a spontaneous model of human ovarian cancer. METHODS SPB1 mRNA expression in normal ovary (n=20) and ovarian tumors (n=23) was evaluated by RT-PCR. Relative levels of mRNA were compared by quantitative RT-PCR (qRT-PCR) in selected samples. SELENBP1 protein expression was evaluated by 1D Western blot and immunohistochemistry with a commercial anti-human SELENBP1 antibody. RESULTS SELENBP1 mRNA and protein was expressed in 100% of normal and ovarian tumors and qRT-PCR confirmed decreased mRNA expression in 80% of ovarian tumors. SELENBP1 was primarily localized in surface epithelial cells of normal ovaries. In ovaries containing early tumor lesions, SELENBP1 expression was reduced in the surface epithelium near the tumor and was expressed in tumor cells, while more distant regions with normal histology retained SELENBP1 expression in the surface epithelium. CONCLUSIONS We have shown for the first time that SELENBP1 is expressed in both normal ovaries and ovarian tumors in the hen and that SELENBP1 expression is altered in the vicinity of the tumor. Furthermore, SELENBP1 expression in normal ovarian surface epithelium and in ovarian tumors parallels that previously reported for ovarian cancer in women.

Detection of Ovarian Tumors in Chicken by Sonography A Step Toward Early Diagnosis in Humans

Animal models of spontaneous ovarian cancer are important for understanding early tumor development. Ovarian imaging may play an important role in following changes in tumor development. Laying hens are the only animals that develop spontaneous ovarian cancer similar to humans. The aim of this study was to determine the feasibility of detecting ovarian tumors in laying hens using sonography.

Anti‐tumor and Anti‐ovarian Autoantibodies in Women with Ovarian Cancer

There is a lack of validated marker(s) for the diagnosis of early‐stage ovarian cancer (OVCA). The objective was to determine if women with OVCA had antibodies, to assess their potential as markers of ovarian cancer. The secondary objective was to compare the prevalence of antibodies to proteins from normal ovary and ovarian tumors to determine if antibodies primarily recognize tumor antigens, as many antigens are common to tumor and normal ovary.

Prevalence of antitumor antibodies in laying hen model of human ovarian cancer.

Antitumor antibodies are associated with tumors in human cancers. There is relatively little information on the timing and progression of antibody response to tumors. The objective of the study was to determine if spontaneous ovarian cancer in the egg-laying hen is associated with antitumor antibodies. Antibodies were detected by immunoassay and immunoblotting using proteins from normal ovary and ovarian tumors. Candidate antigens were identified by mass spectrometry of immunoreactive spots cut from 2-dimensional gels and Western blot. Antitumor (serum reacting against tumor ovarian extract) and antiovarian (serum reacting against normal ovarian extract) antibodies were significantly associated with ovarian cancer (67%; P ≤ 0.001) compared with normal control hens. Hens with abnormal histology but no gross tumor had antitumor antibodies (63%; P ≤ 0.025) but not antiovarian antibodies. There were common as well as different immunoreactions against normal ovary and homologous and heterologous tumor proteins in 2-dimensional Western blots. The candidate antigens included those commonly associated with human cancers and other diseases such as vimentin, apolipoprotein A1, Annexinn II, enolase, DJ-1, and so on. The results suggest that antitumor antibodies are associated with ovarian cancer in hens, similar to human ovarian cancer. The egg-laying hen may be a model for understanding the antitumor humoral immune response, particularly at early tumor stages that are not readily accessible in human ovarian cancer.

Association of interleukin 16 with the development of ovarian tumor and tumor-associated neoangiogenesis in laying hen model of spontaneous ovarian cancer.

Objective Tumor-associated neoangiogenesis (TAN) is an early event in ovarian tumor development. Interleukin 16 (IL-16) is a proangiogenic cytokine that stimulates production of neoangiogenic factors. The goal of this study was to determine the association of IL-16 with tumor development and ovarian TAN in laying hens, an animal model of spontaneous ovarian cancer (OVCA). Methods Sera and ovarian tissues from 3-year-old laying hens were collected and processed for histopathologic, immunoassay, immunohistochemistry, immunoblotting, and molecular biological studies to determine the tissue expression and serum levels of IL-16. Samples were divided into 3 groups based on the diagnosis of the histopathologic ovarian tissue examination, namely, normal (healthy control, n = 81), early (n = 23 including 11 with microscopic OVCA), and late stages (n = 16) of OVCA. Results Serum levels of IL-16 were significantly higher in hens with microscopic, early, and late stages of OVCA than normal hens (P < 0.0001). The frequencies of IL-16+cells in tumor-bearing ovaries were significantly higher than normal hens (P < 0.05). The expression of IL-16 protein and mRNA were stronger in tumor-bearing ovaries than normal ovaries. In addition to ovarian stroma, IL-16 was also expressed by the epithelial cells of the tumor in OVCA hens. Differences in serum levels and ovarian IL-16 expression were not significant among different histological subtypes of OVCA including serous, endometrioid, and mucinous. Similar to the serum levels and ovarian expression of IL-16, the densities of neoangiogenic microvessels were significantly higher in hens with tumor-bearing ovaries than normal hens. Conclusions The results of the study suggest that changes in serum levels of IL-16 are associated with tumor development and TAN. Thus, serum IL-16 levels may be an indicator of ovarian TAN at the early stage of OVCA.

Autoantibodies to Mesothelin in Infertility

Background: According to extensive epidemiologic data, infertility is associated with increased ovarian cancer risk. Previous studies showed that both women with infertility and those with ovarian cancer have autoantibodies to ovarian antigens. The objective was to determine if women with infertility have antibodies to mesothelin, a well-characterized ovarian cancer antigen. Methods: Sera were obtained from women with infertility (n = 109), ovarian cancer (n = 28), benign ovarian tumors or cysts (n = 24), and from healthy women (n = 152). Infertility included those with a risk for ovarian cancer; endometriosis (n = 23), ovulatory dysfunction (n = 17), premature ovarian failure (POF; n = 25) and unexplained infertility (n = 44). Sera were assayed for mesothelin antibodies and for circulating mesothelin antigen by immunoassay and compared with assay control sera (n = 16) to determine a positive result. Results: Mesothelin antibodies were significantly more frequent in women with prematurely reduced ovarian function including ovulatory dysfunction (59%), ovarian failure (44%) and unexplained infertility (25%) compared with controls. In contrast, women with endometriosis, who also have a high risk for ovarian cancer, did not have mesothelin antibodies. Serum levels of mesothelin were rarely elevated in women with infertility but were high in most patients with ovarian cancer. Conclusions and Impact: We show for the first time that antibodies to mesothelin, a well-characterized ovarian cancer antigen, occur in some women with epidemiologic risk for ovarian cancer. The results suggest it may be possible to identify which women with infertility have ovarian cancer risk. Cancer Epidemiol Biomarkers Prev; 20(9); 1970–8. ©2011 AACR.