CA 125 in the epithelium closely related to the embryonic ectoderm: the periderm and the amnion

Update review on five top clinical applications of human amniotic membrane in regenerative medicine

Due to the increasing number of studies performed in the field of regenerative medicine during the last two decades, more analytic studies are still needed to clarify the future prospect of this area of science. The main aim of this research was to review the clinical applications of human Amniotic membrane in the field of regenerative medicine critically. Furthermore, in the light of increasing numbers of available products derived from amniotic membrane, we aimed look in depth to see whether regenerative medicine research strategies have a place in the clinical setting. More specifically, in the present study, we attempted to provide insight on developing the new indication for more research and in the next step, for market leaders companies to expand cost-effectiveness of new derived AM products. 20 companies or distributers have offered some commercial products in this field. Survey on more than 90 clinical trials in last five years showed dermatology (and more specific wound healing), orthopedic, and ophthalmology are heavily biased toward multibillion dollar industry. Moreover, urology and dentistry with fewer numbers of clinical data in comparison with the above-mentioned areas, currently are in the path of translation (especially dentistry). In addition, otolaryngology and oncology with the lowest number showed more potential of research thorough understanding the properties that will help guiding the use of AM-derived products in these two areas in future. More than 50% of clinical studies were done or are developing in USA, which have the biggest share in market products. Subsequently, China, Egypt, India, Iran, and Germany with the ongoing clinical trials in different phases may have more approved products in near future.

The Bottlenecks in Translating Placenta-Derived Amniotic Epithelial and Mesenchymal Stromal Cells Into the Clinic: Current Discrepancies in Marker Reports

Placenta-derived amniotic cells have prominent features for application in regenerative medicine. However, there are still discrepancies in the characterization of human amniotic epithelial and mesenchymal stromal cells. It seems crucial that the characterization of human amniotic membrane cells be investigated to determine whether there are currently discrepancies in their characterization reports. In addition, possible causes for the witnessed discrepancies need to be addressed toward paving the way for further clinical application and safer practices. The objective of this review is to investigate the marker characterization as well as the potential causes of the discrepancies in the previous reports on placenta-derived amniotic epithelial and mesenchymal stromal cells. The current discrepancies could be potentially due to reasons including passage number and epithelial to mesenchymal transition (EMT), cell heterogeneity, isolation protocols and cross-contamination, the region of cell isolation on placental disk, measuring methods, and gestational age.

The diagnostic value of beta-human chorionic gonadotropin, progesterone, CA125 in the prediction of abortions

This study was conducted to investigate the effectiveness of serum levels of free beta-hCG, progesterone, CA125 and their combined use in the prediction of first trimester abortions. A total of 140 singleton pregnant women between 5 and 13 weeks' gestational age were included as Group I (n = 21) who resulted in abortion including missed abortion, incomplete abortion, complete abortion and inevitable abortion; Group II (n = 129) included normal pregnancies. When using the free beta-hCG level of <20 ng/ml as a cut off point, the sensitivity, specificity, PPV and NPV were 91%, 82%, 46% and 98%, when using a progesterone of <15 ng/ml as a cut off point, they were 91%, 89%, 59%, 98%. The single measurement of free beta-hCG or progesterone levels can be useful in the prediction of first trimester spontaneous abortions, but using progesterone may be recommended since it has high availability and low cost.

MUC16 expression during embryogenesis, in adult tissues, and ovarian cancer in the mouse

Cancer antigen 125 (CA125) is an antigen that is elevated in the serum of women with ovarian carcinoma, but can also be detected in serum from healthy women. CA125 is expressed in 80% of human ovarian cancers, as well as in normal adult endometrium, lung, and amnion. The gene encoding human CA125 was identified as MUCIN16 (MUC16). A database search identified the orthologous mouse gene, Muc16. Reverse transcription-polymerase chain reaction and RNA in situ hybridization detected Muc16 transcripts in the surface epithelia of the upper respiratory tract, the mesothelia lining body cavities and the internal organs, as well as male and female reproductive organs, and the amnion. Antibodies raised against human MUC16 do not recognize mouse MUC16. Therefore, a rabbit anti-mouse polyclonal antibody against recombinant mouse MUC16 was generated. Immunohistochemistry using this anti-mouse MUC16 antibody revealed expression in the luminal epithelia of the trachea, the epithelia of the secretory glands in the oral cavity, the surface of the olfactory epithelia, as well as mesothelial cells lining body cavities (i.e., pleural, peritoneal, and pelvic cavities), and male and female reproductive organs. In addition, MUC16 protein was detected in other cell types, such as the surface epithelia of the cochlear duct and chief cells of the stomach, suggesting multiple roles for MUC16. In mouse serous epithelial ovarian cancer, MUC16 protein was detected at the apical surface of well-differentiated tumors, but not poorly differentiated tumors. These findings document the presence of MUC16 in murine ovarian cancer and in normal tissues and provide a foundation for future functional studies.

The potential of amniotic membrane/amnion-derived cells for regeneration of various tissues

Regenerative medicine is a new field based on the use of stem cells to generate biological substitutes and improve tissue functions, restoring damaged tissue with high proliferability and differentiability. It is of interest as a potential alternative to complicated tissue/organ transplantation. Recently, amnion-derived cells have been reported to have multipotent differentiation ability, and these cells have attracted attention as a cell source for cell-transplantation therapy. The amnion possesses considerable advantageous characteristics: the isolated cells can differentiate into all three germ layers; they have low immunogenicity and anti-inflammatory functions; and they do not require the sacrifice of human embryos for their isolation, thus avoiding the current controversies associated with the use of human embryonic stem cells. Moreover, we developed human amniotic cell-sheets using a novel culture surface coated with a noncytotoxic, temperature-responsive elastic protein-based polymer. We also generated a "hyper-dry-amnion", which has already been applied clinically in the ophthalmological field. Compared to cryopreserved fresh amnion, "hyper-dry-amnion" is easy to handle and has started to bring good results to patients. These materials from the amnion are also expected to open a new field in tissue engineering. Thus, amnion, which had been discarded after parturition, has started to be appreciated as an attractive material in the field of regenerative medicine. In this review, the most recent and relevant clinical and experimental data about the use of amniotic membrane and cells derived from it are described.

The amniotic membrane in ophthalmology

The amniotic membrane is the innermost of the three layers forming the fetal membranes. It was first used in 1910 in skin transplantation. Thereafter it has been used in surgical procedures related to the genito-urinary tract, skin, brain, and head and neck, among others. The first documented ophthalmological application was in the 1940s when it was used in the treatment of ocular burns. Following initial reports, its use in ocular surgery abated until recently when it was re-discovered in the Soviet Union and South America. Its introduction to North America in the early 1990s heralded a massive surge in the ophthalmic applications of this membrane. The reintroduction of amniotic membrane in ophthalmic surgery holds great promise; however, although it has been shown to be a useful and viable alternative for some conditions, it is currently being used far in excess of its true useful potential. In many clinical situations it offers an alternative to existing management options without any distinct advantage over the others. Further studies will undoubtedly reveal the true potential of the membrane, its mechanism(s) of action, and the effective use of this tissue in ophthalmology.

Serum CA 125 levels and spontaneous abortion

OBJECTIVE

Previous reports have suggested that serum CA 125 levels in patients who spontaneously abort in the first trimester of pregnancy differ from the levels of patients who successfully complete their pregnancies. Low CA 125 levels have been suggested to predict spontaneous abortion, although an increased rate of first-trimester spontaneous abortion has also been reported in women with elevated CA 125 levels early in pregnancy. The purpose of this study was to prospectively compare serum CA 125 levels of women who abort in the first trimester with levels of those women whose pregnancies progress beyond 12 gestational weeks.

STUDY DESIGN

A total of 188 pregnant patients had weekly serum CA 125 levels obtained after a prepregnancy baseline value was determined. Levels of the antigen in women who ultimately had a first-trimester spontaneous abortion were compared with CA 125 levels from women whose pregnancies continued past the first trimester.

RESULTS

There was no statistically significant difference in the CA 125 levels of patients who aborted compared with those of women whose pregnancies continued. In addition, among patients with CA 125 values > 150 U/ml there was also no statistically significant difference in the proportion of patients who aborted compared with controls.

CONCLUSION

Serum CA 125 levels are not predictive of spontaneous abortion in the first trimester of pregnancy.

Epidermal growth factor enhances secretion of the ovarian tumor-associated cancer antigen CA125 from the human amnion WISH cell line

OBJECTIVE

We studied the relation between epidermal growth factor (EGF)/epidermal growth factor receptor (EGFR) and CA125 production in WISH cells.

METHODS

We investigated quantitatively and immunohistochemically EGF-stimulated CA125 release from WISH cells and the effect of EGF on CA125 phosphorylation.

RESULTS

Immunohistochemical staining demonstrated that CA125 and EGFR expression on the plasma membrane of the WISH cells was closely correlated with cell density. The WISH cell monolayers (day 4) stained for CA125 in both the cytoplasm and plasma membrane. By day 8, cells began to form clumps in the surrounding monolayer that were positive for membrane-associated CA125 and EGFR, while the monolayer was almost negative for both molecules. Four-day and 8-day cells exposed to EGF demonstrated a loss of both CA125 and EGFR staining. Epidermal growth factor increased the secreted CA125 levels by 50% in day-4 cells but had no effect on day-8 cells. CA125 from WISH cells was phosphorylated, and EGF further enhanced this phosphorylation.

Second-trimester cancer antigen 125 and Down's syndrome

This study explores if assay of cancer antigen 125 (CA 125) in maternal serum might aid the detection of Down's syndrome in the second trimester of pregnancy. CA 125 levels were determined retrospectively in stored maternal serum samples from ten Down's syndrome pregnancies and 78 controls matched for gestational and maternal age. In addition, second-trimester amniotic fluid samples from nine Down's syndrome and 109 unaffected pregnancies were analysed for CA 125. Maternal serum CA 125 values for Down's syndrome pregnancies were lower, with the median being 0.72 multiples of the unaffected population median. The medians for affected and unaffected pregnancies did not differ significantly and there was a considerable overlap in the range of values of cases and controls. The distribution of amniotic fluid CA 125 levels for Down's syndrome pregnancies resembled that for controls. From our present results, we could not find an association between Down's syndrome and second-trimester maternal serum or amniotic fluid CA 125 levels.

The prognostic significance of maternal serum CA125 measurement in threatened abortion

The prognostic predictive value of maternal serum CA125 measurement was investigated in 25 cases of threatened abortion. The women were non-smoker, had a ultrasonographically verified viable single fetus, and the gestational ages ranged from 7 to 12 weeks. Twenty-five healty pregnant women, with the same characteristics were used as the control group. The overall abortion rate was found to be 20% (5/25) in the study group. In serial measurements the mean serum CA125 level of the patients with an unfavorable pregnancy outcome was significantly higher than that of the patients with a favorable outcome. When the cut-off level of maternal serum CA125 was taken as > 65 U/ml in the first and > 60 U/ml in the second measurements of the study group, the risk of termination of the pregnancy by spontaneous abortion was 83.3% in the patients with elevated serum CA125 levels. No statistically significant difference was observed with respect to the duration of vaginal bleeding between the aborters and the patients with a favorable outcome. Nevertheless, when vaginal bleeding had been present for 3 days or more and there was high maternal serum CA125 activity, the abortion risk was found to be 100% (3/3). These findings suggest that the maternal serum CA125 measurement in threatened abortion can be useful to determine the extent of decidual destruction which is directly related to the outcome of pregnancy.

Expression of CEA, CA-125 and SCC antigen by biological fluids associated with pregnancy

Carcinoembryonic antigen (CEA), cancer antigen 125 (CA-125) and squamous cell carcinoma (SCC) antigen were measured in 56 full-termed pregnancies by enzyme-immunoassays (EIA-MEIA). The measurements were done in maternal serum (MS), umbilical cord blood (UCB) and amniotic fluid (AF) samples, during delivery. Very high antigen levels were found in AF samples (median: CEA = 124 ng/ml; CA-125 = 710 U/ml; SCC = 710 ng/ml) compared to UCB and MS. CEA and SCC showed significantly lower values in MS (0.6 and 1.7 ng/ml, respectively) than in UCB (1.6 ng/ml, P = 7.7 x 10(-9); 3.55 ng/ml, P = 6.5 x 10(-6), respectively), while CA-125 had significantly higher values in MS (6 U/ml) than in UCB (0.0 U/ml, P = 17 x 10(-6); Wilcoxon paired test). All CEA values in MS were below cut-off (less than or equal to 5 ng/ml), while 10% of CA-125 and 30% of SCC values were above cut-off (less than or equal to 35 U/ml and less than or equal to 2.5 ng/ml, respectively). Amniotic fluid CEA with meconium had higher values (P = 0.0002), while the highest CA-125 values in AF samples were found in primiparae (P = 0.02). Moreover SCC in AF samples from vaginal delivered pregnancies showed significantly higher values, compared to those from cesarean section (P = 4.2 x 10(-7); Mann-Whitney U-test). Thus, our findings suggest that pregnancy has an influence on maternal serum SCC and CA-125 values, while CEA is independent of gestation and seems to conserve its diagnostic value during pregnancy as well.

Secondary müllerian system and endometriosis

The pathogenesis of endometriosis is controversial. The two principal histogenetic theories are (1) metastases of endometrial tissues to an ectopic location (metastatic theory) and (2) metaplastic development of endometrial tissue at the ectopic site (metaplastic theory). Studies on the development of the coelomic cavity and the müllerian duct, as well as expression of CA 125 during the fetal period and in the adult, strongly suggest that coelomic epithelium-related tissues and müllerian-derived epithelia of the adult have a shared embryologic ancestry. Many manifestations of müllerian-directed metaplasia suggest that tissues derived from the coelomic epithelium and its accompanying mesenchymal cells, referred to as the "secondary müllerian system," have the potentiality to differentiate into müllerian-directed epithelium and stroma. This metaplastic potentiality of the secondary müllerian system constitutes a basic concept in the pathogenesis of endometriosis.

Immunohistochemical localization of CA130 in fetal tissues, and in normal and neoplastic tissues of the female genital tract

A murine monoclonal antibody, 130-22, produced against a human lung adenocarcinoma cell line (PC-9) has been suggested as recognizing an antigenic determinant (CA130) which is different from an epitope recognized by OC125 on CA125 glycoprotein molecules. The immunohistochemical reactivity with the 130-22 antibody (anti-CA130) was examined in human fetal tissues, and normal and neoplastic tissues of female genital tracts, and compared to those using OC125. Among the fetal tissues, the amnion and the cells of coelomic epithelium and mullerian-derived epithelia reacted with anti-CA130. In normal adult tissues, cervical and endometrial gland cells, tubal epithelial cells, and ovarian surface cells reacted with anti-CA130. In addition, predecidual cells in the late secretory endometrium and decidual cells during gestation were positive. Among the neoplastic tissues, tubal and endometrial adenocarcinomas and epithelial ovarian tumors were positive for anti-CA130. There were no differences in the respective specimens between the immunohistochemical localization of anti-CA130 and of OC125. Therefore, anti-CA130 is considered to be useful in the immunohistochemical detection of CA125 glycoprotein molecules as well as OC125.

Distribution of CA 125 in embryonic tissues and adult derivatives of the fetal periderm

New murine monoclonal antibodies to a partially purified CA 125 antigen were developed and identified as M 2 and M 11. With immunohistochemical techniques, these new antibodies and OC 125 antibody were used to search for CA 125 in embryonic tissues and adult apocrine sweat glands and mammary glands. The embryonic skin, the periderm, expressed CA 125 antigen and its adult derivatives, the mammary glands and apocrine sweat glands, expressed CA 125 while in the active state of secretion. In a 6-week-old formalin-fixed and paraffin-embedded ectopic embryo specimen, antibodies M 2 and M 11 recognized CA 125 in the periderm, the notochord, the myocardium, the pericardium, the gastroenteric tract, enteric duct remnants in the umbilical cord (vitelline and allantoic ducts), the mesonephric duct, and the amnion. OC 125 staining of these formalin-fixed specimens was either very faint or absent. In a formalin-fixed and paraffin-embedded specimen of apocrine sweat glands from the axilla, antibodies M 2 and M 11 detected CA 125 antigen intracellularly in the secretory cells. Again no staining was observed with OC 125 antibody. In a frozen and acetone-fixed specimen of lactating mammary glands, antibodies M 2 and OC 125 detected CA 125 antigen intraductally. Colostrum and milk collected from 25 mothers at various stages post partum had mean CA 125 levels of 34,213 U/ml in colostrum, 1469 U/ml at 3 to 7 days, and 105 U/ml at 5 to 26 weeks.