The Role of RCAS1 and oxytocinase in immune tolerance during pregnancy

Molecular Changes on Maternal-Fetal Interface in Placental Abruption-A Systematic Review

Placental abruption is the separation of the placenta from the lining of the uterus before childbirth. It is an infrequent perinatal complication with serious after-effects and a marked risk of maternal and fetal mortality. Despite the fact that numerous placental abruption risk factors are known, the pathophysiology of this issue is multifactorial and not entirely clear. The aim of this review was to examine the current state of knowledge concerning the molecular changes on the maternal–fetal interface occurring in placental abruption. Only original research articles describing studies published in English until the 15 March 2021 were considered eligible. Reviews, book chapters, case studies, conference papers and opinions were excluded. The systematic literature search of PubMed/MEDLINE and Scopus databases identified 708 articles, 22 of which were analyzed. The available evidence indicates that the disruption of the immunological processes on the maternal–fetal interface plays a crucial role in the pathophysiology of placental abruption. The features of chronic non-infectious inflammation and augmented immunological cytotoxic response were found to be present in placental abruption samples in the reviewed studies. Various molecules participate in this process, with only a few being examined. More advanced research is needed to fully explain this complicated process.

Breast cancer, placenta and pregnancy

BACKGROUND

Breast cancer is one of the most frequently diagnosed malignancies during pregnancy. Tumours often present characteristics of high malignancy and are hormone receptor negative/HER2 positive or triple negative. In general, pregnancy, including the postpartum period, is associated with a transiently increased risk of developing breast cancer but followed by a long-lasting protective period. Placental metastases are very rare and, thus far, breast cancer metastases in the foetal compartment have not been described. To discuss these apparently contradictory observations, this narrative review resumes immunological and hormonal alterations during pregnancy potentially affecting breast cancer risk as well as tumour growth and behaviour.

OBSERVATIONS

Upregulation of breast cancer-associated genes involved in immunological and reproductive processes has been observed in parous women and is potentially responsible for a transiently increased risk in pregnancy. In contrast, maternal immunisation and immunoglobulin production against antigens expressed on trophoblast cells, such as specific glycosylation patterns of mucin-1 or RCAS1-associated truncated glycans, seem to prevent breast cancer development in later years. Animal and human studies indicate that T cells are involved in these processes. Several placenta-derived factors, especially kisspeptin, have direct anti-tumour effects. The pregnancy-related increase of estrogen, progesterone, and other hormones influence growth and characteristics of breast cancer while the role of further placenta-secreted factors is still controversially discussed.

CONCLUSION

Several factors and cells are involved in altered breast cancer risk during and after pregnancy and have potential for developing novel treatment strategies in future.

Endometriosis node in gynaecologic scars: a study of 17 patients and the diagnostic considerations in clinical experience in tertiary care center

Background

Endometriosis nodes are observed in extra pelvic locations, particularly in gynaecological scars, with the abdominal wall being one of the most frequent locations. The main objective of the study is to review patient characteristics of cases of endometriosis nodes in gynaecological scars.

Methods

A retrospective, observational and descriptive study with a cohort of patients from Hospital 12 de Octubre was conducted from January 2000 to January 2012. We analysed all of the patients who presented with an endometriosis node in a gynaecological scar presentation who had undergone surgery in that period. Descriptive data were collected and analysed.

Results

A total of 17 patients with an anatomopathological diagnosis of an endometriosis node in a gynaecological scar were found. The following variables were studied: the age at diagnosis (32.5 years +/− 5.5 years), personal and obstetric history, time from surgery to diagnosis (4.2 years +/− 3.4 years), symptoms (a painful mass that grows during menstruation is the most frequent symptom in our patients), technical analyses by computed tomography (CT), magnetic resonance (MR) or fine needle aspiration (FNA) (77% of the patients), node size (2.5 cm +/− 1.1 cm) and location (caesarean scar, 82%; episiotomy scar, 11.7%; and laparoscopic surgery port, 5.8%), involvement of adjacent structures (29% of the patients), treatment (exeresis with a security margin in all the patients) and other endometriosis locations (14% of the patients).

Conclusions

A high level of suspicion is required to diagnose gynaecological scar endometriosis, which should be suspected in the differential diagnosis of scar masses in reproductive-aged women.

Several theories have been proposed to explain the formation of endometriosis nodes in extrauterine localizations. The two of them that seem to be more plausible are the metaplasia and transport theories.

Imaging with ultrasound, CT and MR facilitate the diagnosis. FNA could be used for preoperative diagnosis.

Treatment must be by node resection with a security margin. In some cases, surgery could be combined with hormonal treatment.

Electronic supplementary material

The online version of this article (doi:10.1186/s12905-015-0170-9) contains supplementary material, which is available to authorized users.

Maternal blood serum and plasma human tumor-associated antigen RCAS1 during the course of uncomplicated pregnancies: a prospective study

PROBLEM

we aimed to investigate the expression of the tumor-associated RCAS1 protein in maternal blood of uncomplicated pregnancies.

METHOD OF STUDY

maternal blood was obtained from women with uncomplicated pregnancies (N = 43) at 11-13, 20-22, 32-34, 37-38 weeks of gestation, and immediately after delivery. Serum RCAS1 concentration was studied by ELISA, and plasma mRNA was subjected to real-time (RT)-PCR.

RESULTS

serum RCAS1 protein concentration was significantly up-regulated at 11-13 and 20-22 weeks than that at 32-34 weeks and after delivery. RCAS1 mRNA level was significantly increased at 11-13 weeks than that at 37-38 weeks. A significant positive correlation was defined between RCAS1 serum concentration at 11-13 weeks and gestational age at delivery and that between plasma RCAS1 mRNA levels at 37-38 weeks and umbilical cord blood base excess. A significant negative correlation was found between RCAS1 serum concentration at 37-38 weeks and umbilical cord blood pH at delivery.

CONCLUSIONS

RCAS1 protein might have importance in the development of uncomplicated pregnancies and for the prediction of pregnancy outcome.

Placental leucine aminopeptidase- and aminopeptidase A- deficient mice offer insight concerning the mechanisms underlying preterm labor and preeclampsia

Preeclampsia and preterm delivery are important potential complications in pregnancy and represent the leading causes for maternal and perinatal morbidity and mortality. The mechanisms underlying both diseases remain unknown, thus available treatments (beta2-stimulants and magnesium sulfate) are essentially symptomatic. Both molecules have molecular weights less than 5–8 kDa, cross the placental barrier, and thus exert their effects on the fetus. The fetus produces peptides that are highly vasoactive and uterotonic and increase in response to maternal stress and with continued development. Fetal peptides are also small molecules that inevitably leak across into the maternal circulation. Aminopeptidases such as placental leucine aminopeptidase (P-LAP) and aminopeptidase A (APA) are large molecules that do not cross the placental barrier. We have shown that APA acts as an antihypertensive agent in the pregnant spontaneously hypertensive rat by degrading vasoactive peptides and as a result returns the animal to a normotensive state. P-LAP also acts as an antiuterotonic agent by degrading uterotonic peptides and thus prolongs gestation in the pregnant mouse. Given the ever increasing worldwide incidences of preeclampsia and preterm labor, it is imperative that new agents be developed to safely prolong gestation. We believe that the use of aminopeptidases hold promise in this regard.

The effect of tumor-associated protein RCAS1 gene silencing on blood pressure and urinary protein excretion in pregnant mouse: a pilot study

OBJECTIVE

The level of tumor-associated receptor-binding cancer antigen that is expressed on SiSo cells (RCAS1) is decreased significantly in preeclamptic pregnancies. We hypothesized that RCAS1 protein gene silencing might affect blood pressure and proteinuria in pregnant mice.

STUDY DESIGN

On postcoital day 7.5, pregnant imprinting control region mice were subjected to the transfer of small interfering RNA (siRNA) against RCAS1 protein into the uterine cavity with the use of a hemagglutinating virus Japan envelope. Scramble siRNA was used as a negative control. Blood pressure and urine albumin/creatinine measurements were performed. The effect of the transferred siRNA was examined in uterine samples on postcoital day 8.5 with the use of Western blotting and immunohistochemistry analyses.

RESULTS

In the RCAS1 siRNA group, blood pressure significantly raised on postcoital days 9.5, 10.5, 11.5, and 15.5, whereas urine albumin/creatinine ratio was significantly increased on postcoital day 9.5

CONCLUSION

Our results suggest the importance of RCAS1 protein in the pathophysiologic condition of preeclampsia.

Physiological and pathophysiological roles of placental aminopeptidase in maternal sera: possible relation to preeclampsia and preterm delivery

BACKGROUND

Both preeclampsia and preterm delivery are important complications in pregnancy and are still diseases of unknown causes, despite considerable research in recent times. These complications constitute obstetric emergencies that require expert knowledge and management skills.

OBJECTIVES

This article reviews the emerging role of aminopeptidases in the monitoring and development of improved therapeutic strategies that provide better patient selection for therapeutic personalization.

METHODS

A literature review (PubMed, Medline) to the present.

RESULTS/CONCLUSION

The fetus produces angiotensin II, vasopressin and oxytocin, which are highly vasoactive and uterotonic, and these peptides increase in parallel with fetal growth and in response to stressors such as hypoxia. Because these hormones are small molecules, it is probable that there occurs the leak out of these hormones from the feto-placental unit. Oxytocinase and angiotensinase in human placenta are identical to placental leucine aminopeptidase and aminopeptidase A, respectively. They work as barriers of peptide hormones between fetus and mother and their activities in pregnancy sera increase with advancing gestation. Aminopeptidase activities in maternal sera might be useful for monitoring of preeclampsia and predicting the prognosis of preterm delivery.

The association between RCAS1 expression in laryngeal and pharyngeal cancer and its healthy stroma with cancer relapse

BACKGROUND

The purpose of this study has been to establish the level of RCAS1 - a membrane protein expressed in various cancer cells and able to induce apoptosis of CTLs and NK cells in pharyngeal and laryngeal cancer and its clear surgical margin - with respect to clinicopathological features and to patient's follow up and evaluate its possible role in cancer relapse.

METHODS

A total of 122 tissue samples were obtained: 51 samples from laryngeal and pharyngeal squamous cell carcinoma, 51 samples from the clear surgical margins of these tumors, and 20 tissue samples derived from the healthy mucous membranes of the upper respiratory tract mucosa of patients without cancerous tumors. Patients were observed for a total of 4 years following surgical treatment. The level of RCAS1 expression was assessed by immunohistochemistry and Western blot.

RESULTS

RCAS1 was identified in all laryngeal and pharyngeal carcinomas and in almost all the clear surgical margin samples. The level of RCAS1 expression was significantly higher in the cancerous samples than in the clear surgical margins and was determined to be related to the grade of the cancer and the presence of lymph node metastases. In cases of cancer relapse, significantly higher levels of RCAS1 expression were observed in the clear surgical margins.

CONCLUSION

Selective cytotoxic immune cell suppression concomitant with tumor growth and associated with RCAS1 expression seems to be an important event connected with cancer relapse.

The possible correlation between the patient's immune tolerance level during cesaerean section and the incidence of subsequent emergency peripartum hysterectomy

Introduction. Cesarean section is an independent risk factor for peripartum hysterectomy. As a method of delivery, cesarean section may interfere with a number of molecular changes that occur at the maternal-fetal interface during the course of labor. Methods. The level of CD3, CD56, CD25, and CD69 antigen immunoreactivity was assessed by immunohistochemistry in 26 decidual tissue samples. The tissue samples were obtained from 18 women who underwent cesarean sections at term and from 8 women who underwent cesarean hysterectomies. Results. An increase in the activity and infiltration of immune cells in the decidua sampled during the spontaneous beginning of labor was observed. The further progression of labor was accompanied by a decrease in the number and activity of immune cells. The number of CD56+ and CD3+ cells in the decidua was statistically significantly lower in patients who had undergone cesarean hysterectomies than in those who had had cesarean sections at term. Conclusion. Abnormal immune response during labor may increase the risk for peripartum hysterectomy.

The human tumor-associated antigen RCAS1 in pregnancies complicated by pre-eclampsia

The human tumor-associated antigen RCAS1 (receptor-binding cancer antigen expressed on SiSo cells) is considered to play a role in the escape of tumor cells from immune surveillance and, at the same time, participates in the inhibition of the maternal immune response during pregnancy. The aim of our study was to investigate the expression of tumor-associated RCAS1 protein in the placenta and amniotic membranes and to assess and compare its concentration in amniotic fluid, maternal and cord blood sera in pregnancies complicated by pre-eclampsia. Samples were obtained from women with pre-eclampsia (N=9), pre-eclampsia with IUGR (N=4), normotensive IUGR (N=7) and healthy term controls (N=25) after delivery. Placentas were studied by immunohistochemistry, Western blot analysis and real-time (RT)-PCR. For assessment of RCAS1 protein concentrations in biological fluids, ELISA was performed. RCAS1 mRNA expression in the placentas of pre-eclamptic patients was significantly lower than in controls (p<0.01). The maternal blood serum RCAS1 protein concentration in the pre-eclampsia cases was also significantly lower than in controls (p=0.0207). The other study groups did not differ significantly. This study reveals the possible role of the RCAS1 protein in the development of pre-eclampsia through an immunological pathway.

RCAS1 decidual immunoreactivity during placental abruption: immune cell presence and activity

PROBLEM

RCAS1 is a protein responsible for the suppression of cytotoxic immune response during gestation. The present study evaluates the immunoreactivity level of RCAS1 with respect to immune cell status during placental abruption (PA) and retained placental tissue (RPT).

METHOD OF STUDY

RCAS1, CD3, CD56, CD69 and CD25 immunoreactivity was assessed by immunohistochemistry in 66 decidual samples derived from PA and from RPT.

RESULTS

RCAS1 immunoreactivity was statistically significantly higher in decidual tissue samples derived from patients with RPT than in those derived from patients with PA. A statistically significantly lower number of CD56(+) and CD3(+) cells and immunoreactivity level of CD69 were found in patients with RPT, compared to those with PA.

CONCLUSION

Placental abruption seems to be associated with excessive accumulation and activity of CD3(+) and CD56(+) cells in decidua, which processes might, in turn, result from an insufficient RCAS1 decidual level.

The obstetrical history in patients with Pfannenstiel scar endometriomas--an analysis of 81 patients

INTRODUCTION

The participation of immune tolerance during pregnancy was suggested to be an important factor predisposing to the implantation of decidual cells after cesarean section in Pfannenstiel scar. Delivery at term is related to the termination of immune tolerance to fetal antigens that is maintained throughout pregnancy. Substantial proportion of cesarean section deliveries is performed before the onset of true term labor. The aim of this study was to analyze the clinical symptoms of spontaneous beginning of labor in pregnant women in whom cesarean sections were performed and in whom Pfannenstiel scar endometriomas were observed during follow-up.

MATERIALS AND METHODS

We have retrospectively analyzed 81 patients following the surgical removal of scar endometrioma after cesarean section. Obstetrical histories of cesarean sections in the number of 5,370 preceding the occurrence of the scar endometrioma were analyzed. These data were collected in six different Gynecological and Obstetrical wards in Malopolska Province in Poland. Analysis of data was started by the retrospective evaluation of regular uterine contractions, uterine cervix ripening before cesarean section and the indications for surgery.

RESULTS

In 67 women from the group of 81 patients cesarean sections were performed with unripe uterine cervix and without the presence of regular uterine contractions. Elective indications for cesarean sections were predominant in this group of women. The relative risk of scar endometriomas occurrence following cesarean sections performed before onset of labor in comparison to cesarean sections following spontaneous onset of labor was statistically significantly higher [RR = 2.16, 95% CI = 1.21-3.83; OR = 2.18, 95% CI = 1.22-3.89].

CONCLUSIONS

Cesarean section performed before spontaneous onset of labor may increase substantially the risk of occurrence of scar endometriomas.

Comparison of RCAS1 and metallothionein expression and the presence and activity of immune cells in human ovarian and abdominal wall endometriomas

BACKGROUND

The coexistence of endometrial and immune cells during decidualization is preserved by the ability of endometrial cells to regulate the cytotoxic immune activity and their capability to be resistant to immune-mediated apoptosis. These phenomena enable the survival of endometrial ectopic cells. RCAS1 is responsible for regulation of cytotoxic activity. Metallothionein expression seems to protect endometrial cells against apoptosis. The aim of the present study was to evaluate RCAS1 and metallothionein expression in human ovarian and scar endometriomas in relation to the presence of immune cells and their activity.

METHODS

Metallothionein, RCAS1, CD25, CD69, CD56, CD16, CD68 antigen expression was assessed by immunohistochemistry in ovarian and scar endometriomas tissue samples which were obtained from 33 patients. The secretory endometrium was used as a control group (15 patients).

RESULTS

The lowest metallothionein expression was revealed in ovarian endometriomas in comparison to scar endometriomas and to the control group. RCAS1 expression was at the highest level in the secretory endometrium and it was at comparable levels in ovarian and scar endometriomas. Similarly, the number of CD56-positive cells was lower in scar and ovarian endometriomas than in the secretory endometrium. The highest number of macrophages was found in ovarian endometriomas. RCAS1-positive macrophages were observed only in ovarian endometriomas. CD25 and CD69 antigen expression was higher in scar and ovarian endometriomas than in the control group.

CONCLUSION

The expression of RCAS1 and metallothionein by endometrial cells may favor the persistence of these cells in ectopic localization both in scar following cesarean section and in ovarian endometriosis.

The analysis of RCAS1 and DFF-45 expression in nasal polyps with respect to immune cells infiltration

Background

Nasal polyp constitutes a benign growth process in the nasal and sinus mucosa. RCAS1 (receptor-binding cancer antigen expressed on SiSo cells) is a protein expressed mainly by various human cancer cells. It is not only the marker of cancer process and its expression can also be observed in physiological processes. It is responsible for the regulation of immune cells activity. DFF45 (DNA fragmenting factor) has been described as a substrate for caspase-3. DFF45 seems to play an important role in the onset of apoptotic process by acting probably through the regulation of DNA fragmentation. The aim of the study was to evaluate the ability of nasal polyps to regulate the cytotoxic immune response and to determine their resistance to apoptosis.

Results

The higher RCAS1 level was identified in lymphocytic nasal polyps, the medium one in eosinophilic while the lowest was identified in neutrophilic. DFF-45 expression was higher in eosinophilic than in neutrophilic and lymphocytic nasal polyps.

Conclusion

The changes in DFF-45 level in nasal polyps might indicate a different resistance to apoptosis mediated by immune cells. The alterations in RCAS1 expression indicate that nasal polyps have the ability to regulate the cytotoxic immune response.

The breaking of resistance to immune mediated apoptosis in nasal polyps might have a new therapeutic impact.

Metallothionein expression and infiltration of cytotoxic lymphocytes in uterine and tubal implantation sites

INTRODUCTION

In spite of increasing number of immune cells in the endometrium during the decidualization, the integrity of endometrial tissue in each menstrual cycle is maintained by adaptive changes in expression of several factors that regulate activity of immune cells and concomitant hormonal alterations during the menstrual cycle. This regulatory function of endometrium is also related to resistance to apoptosis, in which metallothionein (MT) may play a role.

MATERIALS AND METHODS

Study group included 26 women with spontaneous abortion and 18 patients with tubal ectopic pregnancy. Control group included 17 women whose endometrial tissue samples were taken during the normal secretory cycle phase. Expression of metallothionein (MT), CD56 and CD69 were assessed in tissue samples by immunohistochemistry.

RESULTS

The number of CD56-positive cells was significantly higher in women with ruptured than unruptured ectopics. MT expression was higher in tubal mucosa distant from the implantation site in ruptured compared to unruptured ectopics. It was found also to be significantly lower than in decidua taken from women with spontaneous abortion. CD69 expression was similar in women with spontaneous abortion as well as patients with ruptured ectopics compared to the control group. On the other hand, CD69 expression in unruptured ectopics was significantly lower than in women with spontaneous abortion and the control group.

CONCLUSION

The concentration of immune cells and increase of their activity in tubal mucosa, with insufficient protection against immune-mediated apoptosis assessed by MT expression, might result in tubal rupture during ectopic pregnancy.

The molecular changes during placental detachment

OBJECTIVES

RCAS1 is a membrane protein that plays a role in the maintenance of maternal immune tolerance during pregnancy. The work presented here demonstrates the results of RCAS1 expression in placenta in cases of placental abruption and patients with retained placental tissue during the third stage of labor.

STUDY DESIGN

The placenta tissue samples were obtained during vaginal and cesarean delivery (derived from 117 pregnancies). Pregnant women were divided into four groups according to the onset of labor and the time of placental detachment in term labors. The samples were analyzed by the Western blot method. Statistical analysis was performed using the Shapiro-Wilk procedure. The Mann-Whitney test and Student's t-test were applied to compare the differences between parametric data.

RESULTS

The average relative amount of RCAS1 observed in those patients with retained placental tissue was statistically significantly higher than in the patients with placental abruption.

CONCLUSION

The differences observed in placental RCAS1 levels confirm the participation of this protein in the inhibition of maternal immune response during gestation. The present results also indicate that RCAS1 participates in the changes in the maternal immune system that take place during parturition and reinforce its potential involvement in the mechanism of placental abruption.

The placental RCAS1 expression during stillbirth

BACKGROUND

Independently of the fetal death cause the beginning and course of stillbirth is closely related with the growing cytotoxic activity at the maternal-fetal interface. RCAS1 participates in the inhibition of maternal immune response during pregnancy. The alterations of RCAS1 protein expression in placental cells seem to determine the beginning of the labor and participate in the placental abruption. The aim of the present study was to investigate RCAS1 expression in placentas obtained following stillbirths or normal term births.

METHODS

RCAS1 expression was evaluated by Western blot method with the use of monoclonal anti-RCAS1 antibody in 67 placental tissue samples. Pregnant women were divided into four groups according to the mode of labor onset--spontaneous or induced, and the type of labor, stillbirth or labor at term. Placental beta-Actin expression was chosen as a control protein. Relative amounts of placental RCAS1 were compared with the use of Student's t-test, whereas beta-Actin control data were compared with the use of Mann-Whitney U test.

RESULTS

The average relative amount of RCAS1 was significantly lower in women with induced stillbirths than in women with induced labor at term. Similarly, significantly lower RCAS1 placental levels were observed in patients with spontaneous stillbirths than in women with spontaneous labor at term. Significant differences in RCAS1 expression were also observed with the respect to the beginning of the stillbirth: spontaneous and induced. Lowest RCAS1 placental levels were observed in women with spontaneous stillbirth.

CONCLUSIONS

These preliminary results indicate that the alterations of RCAS1 expression in the human placenta may be involved in the changes of maternal immune system that take place during stillbirth.