Glycodelin-A expression in the uterine cervix

Pathways regulating the expression of the immunomodulatory protein glycodelin in non‑small cell lung cancer

Glycodelin [gene name, progesterone associated endometrial protein (PAEP)] was initially described as an immune system modulator in reproduction. Today, it is also known to be expressed in several types of cancer, including non‑small cell lung cancer (NSCLC). In this cancer type, the feasibility of its usage as a follow‑up biomarker and its potential role as an immune system modulator were described. It is assumed that NSCLC tumours secrete glycodelin to overcome immune surveillance. Therefore, targeting glycodelin might be a future approach with which to weaken the immune system defence of NSCLC tumours. In this context, it is important to understand the regulatory pathways of PAEP/glycodelin expression, as these are mostly unknown so far. In this study, we analysed the influence of several inducers and of their downstream pathways on PAEP/glycodelin expression in a human lung adenocarcinoma carcinoma (ADC; H1975) and a human lung squamous cell carcinoma (SQCC) cell line (2106T). PAEP/glycodelin expression was notably stimulated by the canonical transforming growth factor (TGF)‑β pathway in SQCC cells and the PKC signalling cascade in both cell lines. The PI3K/AKT pathway inhibited PAEP/glycodelin expression in the ADC cells and an antagonizing role towards the other investigated signalling cascades is suggested herein. Furthermore, the mitogen‑activated protein kinase kinase (MEK)/extracellular‑signal regulated kinases (ERK) pathway was, to a lesser extent, found to be associated with increased PAEP/glycodelin amounts. The phosphoinositide 3‑kinase (PI3K)/protein kinase B (AKT), MEK/ERK pathway and TGF‑β are targets of NSCLC drugs that are already approved or are currently under investigation. On the whole, the findings of this study provide evidence that inhibiting these targets affects the expression of glycodelin and its immunosuppressive effect in NSCLC tumours. Moreover, understanding the regulation of glycodelin expression may lead to the development of novel therapeutic approaches with which to weaken the immune system defence of NSCLC tumours in the future.

The Roles of Glycodelin in Cancer Development and Progression

Glycodelin is a kind of glycoprotein expressed in secretory endometrium, pregnancy deciduas, and amniotic fluid originally, which is vital for the maintenance of normal human reproductive activities. Recent researches have reported that glycodelin is specifically expressed in various malignancies, including female-specific cancers such as endometrial cancer, ovarian cancer and breast cancer, and non-gender specific cancers including lung cancer, and colon cancer, and glycodelin expression correlates with the diagnosis and prognosis of cancer patients. This review focuses on the expression of glycodelin in different cancers and its role in cancer development and progression. Glycodelin possesses the abilities to regulate cancer cell proliferation, differentiation, and invasion, promote cancer angiogenesis, and modulate the differentiation and function of immune cells including T cells, dendritic cells, monocyte-macrophages, natural killer cells and B cells participating in cancer development. The expression of glycodelin can be regulated by stromal cells, lysophosphatidic acid, histone deacetylase inhibitors, and relaxin. In summary, glycodelin is a promising biomarker for the diagnosis and prognosis of cancer patients, and depending on its distinct immunoregulatory effects, glycodelin can be a prospective target for cancer immunotherapy.

Glycodelin expression in pregnant patients with cervical intraepithelial neoplasia: a case-control study

We aimed to evaluate glycodelin immunostaining in pregnant women with a first diagnosis of cervical intraephitelial neoplasia (CIN) and to correlate the expression of CIN with Ki-67 and glycodelin immunostaining. A retrospective case-control study was performed including 20 patients with natural pregnancy and with first time onset of CIN occurring not later than 16 gestational weeks. The control group included 20 non-pregnant patients matched for age, parity, smoking status and number of previous sexual partners. Exclusion criteria included previous cervical treatment, immunocompromised status and chronic hepatitis B and/or C. Staining for Glycodelin and for Ki-67 was expressed using a classification based on the distribution of positivity on a semi-quantitative three-point scale. An inverse relationship was observed between glycodelin immunostaining and CIN grade in pregnant patients (p = 0.01), with a significantly higher expression in CIN1 than in CIN2 and CIN3, but not in non-pregnant patients (p = 0.81). Positivity for Ki-67 was less intense in pregnant than in non-pregnant patients. A significant inverse relationship was observed between glycodelin immunostaining and Ki-67 expression (p = 0.02). We suggest that the higher expression of glycodelin in pregnancy is related to a lower proliferative activity in CIN, which is probably associated to hormonal status of pregnancy. Further clinical studies are needed to support these findings.

Human malignant melanoma-derived progestagen-associated endometrial protein immunosuppresses T lymphocytes in vitro

Progestagen-associated endometrial protein (PAEP) is a glycoprotein of the lipocalin family that acts as a negative regulator of T cell receptor-mediated activation. However, the function of tumor-derived PAEP on the human immune system in the tumor microenvironment is unknown. PAEP is highly expressed in intermediate and thick primary melanomas (Breslow’s 2.5mm or greater) and metastatic melanomas, correlating with its expression in daughter cell lines established in vitro. The current study investigates the role of melanoma cell-secreted PAEP protein in regulating T cell function. Upon the enrichment of CD3⁺, CD4⁺ and CD8⁺ T cells from human peripheral blood mononuclear cells, each subset was then mixed with either melanoma-derived PAEP protein or PAEP-poor supernatant of gene-silenced tumor cells. IL-2 and IFN-γ secretion of CD4⁺ T cells significantly decreased with the addition of PAEP-rich supernatant. And the addition of PAEP-positive cell supernatant to activated lymphocytes significantly inhibited lymphocyte proliferation and cytotoxic T cell activity, while increasing lymphocyte apoptosis. Our result suggests that melanoma cell-secreted PAEP protein immunosuppresses the activation, proliferation and cytotoxicity of T lymphocytes, which might partially explain the mechanism of immune tolerance induced by melanoma cells within the tumor microenvironment.

Progesterone interactions with the cervix: translational implications for term and preterm birth

The uterine cervix plays a vital role in maintaining pregnancy and an equally important role in allowing parturition to occur. Progesterone, either endogenously produced or supplied exogenously, supports the function of the cervix in sustaining intrauterine pregnancy, and the withdrawal of progesterone, either through natural processes or pharmacologic intervention, leads to delivery which underscores the importance of the progesterone's biological activities manifest in normal gestation and pregnancy that ends prematurely. Research crossing many scientific disciplines has demonstrated that progesterone is a pleotropic compound that affects the cervix through cytoplasmic and membrane receptors with profound effects on cellular and molecular functions that influence inflammatory cascades and extracellular matrix, both of which have consequences for parturition. Beyond the local cell and molecular biology of progesterone, it has systemic effects of relevance to pregnancy as well. This paper examines the biology of the cervix from its gross to cellular structure and biological activities of its cell and molecular processes that may be affected by progesterone. The implications of these processes for preterm birth are explored, and direction of current research is in relation to translational medicine implications for diagnostic, prognostic, and therapeutic approaches to threatened preterm birth.

Characterization of the transcriptome of chorioamniotic membranes at the site of rupture in spontaneous labor at term

OBJECTIVE

The purpose of this study was to compare the transcriptome between the site of membrane rupture and the chorioamniotic membranes away from the site of rupture.

STUDY DESIGN

The transcriptome of amnion and chorion (n=20 each) from and distal to the site of rupture from women with spontaneous labor and vaginal delivery at term after spontaneous rupture of membranes was profiled with Illumina HumanHT-12 microarrays. Selected genes were validated with the use of quantitative reverse transcription-polymerase chain reaction.

RESULTS

Six hundred seventy-seven genes were differentially expressed in the chorion between the rupture and nonrupture sites (false discovery rate<0.1; fold change>1.5). Quantitative reverse transcription-polymerase chain reaction confirmed the differential expression in 10 of 14 genes. Enriched biological processes included anatomic structure development, cell adhesion and signal transduction. Extracellular matrix-receptor interaction was the most impacted signaling pathway.

CONCLUSION

The transcriptome of fetal membranes after spontaneous rupture of membranes in term labor is characterized by region- and tissue-specific differential expression of genes that are involved in signature pathways, which include extracellular matrix-receptor interactions.

Functional characterization of the progestagen-associated endometrial protein gene in human melanoma

Utilizing gene microarray profiling of melanoma samples, we have recently identified a novel gene overexpressed in both thick primary and metastatic melanomas. This gene, progestagen-associated endometrial protein (PAEP), has never before been implicated in the oncogenic processes of melanoma, with its true function in oncogenesis and tumour progression relatively unknown. Overexpression of the PAEP gene in freshly procured thick primary and metastatic melanoma samples (58%) and daughter cell lines (77%) is confirmed by quantitative RT-PCR, immunohistochemistry, Western blotting and mass spectrometric analysis. We suggest that PAEP gene overexpression is involved with melanoma tumour progression as well as an aggressive phenotype. Transfection of melanoma cells with PAEP small interfering RNA (siRNA) reveals a significant decrease in soft agar colony formation and a marked inhibition of both cell migration and cell invasion. Furthermore, we establish stable melanoma transfectants via PAEP lentiviral small hairpin RNA (shRNA), examine their growth characteristics in a murine xenograft model and reveal that tumour growth is significantly inhibited in two separate melanoma cell lines. Our data strongly implicate the PAEP gene as a tumour growth promoter with oncogenic properties and a potential therapeutic target for patients with advanced melanoma.

Roles of glycodelin in modulating sperm function

Glycodelin is a glycoprotein with three well-defined isoforms. They are named as glycodelin-S, glycodelin-A and glycodelin-F. The three isoforms have similar protein core but different carbohydrate moieties. Glycodelin-S is abundant in the human seminal plasma. It suppresses sperm capacitation and in doing so, it maintains the spermatozoa in an uncapacitated state before they enter into the uterine cavity. Glycodelin-A is abundant in the amniotic fluid. It is also secreted from endometrial glands into uterine fluid and is produced by the fallopian tube. Glycodelin-A is the first endogenous glycoprotein that was found to inhibit the binding of spermatozoa to the zona pellucida. The immunosuppressive properties of glycodelin-A suggest that the molecule may protect the spermatozoa from immune attack in the maternal reproductive tract. Glycodelin-F was first found in the follicular fluid, hence its name. It also inhibits spermatozoa-zona pellucida binding. In addition, glycodelin-F suppresses progesterone-induced acrosome reaction, and may serve to prevent premature acrosome reaction. Preliminary findings suggest possible presence of yet another glycodelin isoform in the extracellular matrix of cumulus oophorus. Unlike glycodelin-A and -F, it stimulates spermatozoa-zona pellucida binding. In summary, different isoforms of glycodelin have different biological roles on sperm function, and they act in succession to contribute to the success of fertilization.

Glycodelin: a major lipocalin protein of the reproductive axis with diverse actions in cell recognition and differentiation

Glycodelin is a glycoprotein that belongs to the lipocalin superfamily. Depending on glycosylation, glycodelin appears in various isoforms. In the uterus, glycodelin-A is the major progesterone-regulated glycoprotein secreted into uterine luminal cavity by secretory/decidualized endometrial glands. The other tissues expressing glycodelin include fallopian tubes, ovary, breast, seminal vesicle, bone marrow, and eccrine glands. Glycodelin-A potently and dose-dependently inhibits human sperm-egg binding, whereas differently glycosylated glycodelin-S from seminal plasma has no such effect. Absence of contraceptive glycodelin-A in the uterus during periovulatory midcycle is consistent with an open "fertile window." Glycodelin induced by local or systemic administration of progestogens may potentially reduce the fertilizing capacity of sperm in any phase of the menstrual cycle. Glycodelin also has immunosuppressive activity. Its high concentration at the fetomaternal interface may contribute to protection of the embryonic semiallograft. Besides being an epithelial differentiation marker, glycodelin appears to play a role in glandular morphogenesis, as transfection of glycodelin cDNA into a glycodelin-negative breast cancer cells resulted in formation of gland-like structures, restricted proliferation, and induction of other epithelial markers. These various properties, as well as the chemistry, biology, and clinical aspects of glycodelin, continue to be areas of active investigation reviewed in this communication.