Diagnostic applications for inhibin and activins

Tumor Markers and Their Diagnostic Significance in Ovarian Cancer

Ovarian cancer (OC) is characterized by silent progression and late-stage diagnosis. It is critical to detect and accurately diagnose the disease early to improve survival rates. Tumor markers have emerged as valuable tools in the diagnosis and management of OC, offering non-invasive and cost-effective options for screening, monitoring, and prognosis.

PURPOSE

This paper explores the diagnostic importance of various tumor markers including CA-125, CA15-3, CA 19-9, HE4,hCG, inhibin, AFP, and LDH, and their impact on disease monitoring and treatment response assessment.

METHODS

Article searches were performed on PubMed, Scopus, and Google Scholar. Keywords used for the searching process were "Ovarian cancer", "Cancer biomarkers", "Early detection", "Cancer diagnosis", "CA-125","CA 15-3","CA 19-9", "HE4","hCG", "inhibin", "AFP", "LDH", and others.

RESULTS

HE4, when combined with CA-125, shows improved sensitivity and specificity, particularly in early-stage detection. Additionally, hCG holds promise as a prognostic marker, aiding treatment response prediction and outcome assessment. Novel markers like microRNAs, DNA methylation patterns, and circulating tumor cells offer potential for enhanced diagnostic accuracy and personalized management. Integrating these markers into a comprehensive panel may improve sensitivity and specificity in ovarian cancer diagnosis. However, careful interpretation of tumor marker results is necessary, considering factors such as age, menopausal status, and comorbidities. Further research is needed to validate and refine diagnostic algorithms, optimizing the clinical significance of tumor markers in ovarian cancer management. In conclusion, tumor markers such as CA-125, CA15-3, CA 19-9, HE4, and hCG provide valuable insights into ovarian cancer diagnosis, monitoring, and prognosis, with the potential to enhance early detection.

L-carnitine extenuates endocrine disruption, inflammatory burst and oxidative stress in carbendazim-challenged male rats via upregulation of testicular StAR and FABP9, and downregulation of P38-MAPK pathways

We have addressed in the current study the potential of L-carnitine (LC) to extenuate the reproductive toxic insults of carbendazim (CBZ) in male rats, and the molecular mechanisms whereby carnitine would modify the spermatogenic and steroidogenic derangements invoked by the endocrine disruptor. Herein, animals received daily doses of carbendazim (100 mg/kg) by gavage for 8 weeks. Another CBZ-challenged group was co-supplemented with LC (500 mg/kg, IP) twice weekly for 8 weeks. Sperm quantity and quality (morphology, motility and viability), serum testosterone and gonadotropins, and thyroid hormone levels were assessed. Serum tumor necrosis factor alpha (TNF-α), interleukin-6 (IL-6) and interleukin-10 (IL-10) concentrations were determined by ELISA. Oxidant/antioxidant status in rat testis was investigated via measuring testicular contents of malondialdehyde (MDA) and reduced glutathione (GSH), as well as the activities of superoxide dismutase (SOD) and glutathione peroxidase (GPx). Immunohistochemical localizations of the junctional protein; occludin, and inflammatory markers; inducible nitric oxide synthase (iNOS) and nuclear factor kappa beta (NF-κB) were further analyzed. A host of transduction genes that regulate spermatogenic and steroidogenic pathways, and their encoded proteins namely, Steroidogenic Acute Regulatory Protein (StAR), Fatty acid binding protein 9 (FABP9) and P38-mitogen activated protein kinase (P38-MAPK) were assessed by real time quantitative (RT-qPCR) and Western blot. LC improved rat spermiogram, testicular histological alterations and endocrine perturbances, and modulated genes' expressions and their respective proteins. In conclusion, LC effects appear to reside for the most part on its endocrine-preserving, anti-oxidant and anti-inflammatory properties through a myriad of interlaced signal transductions that ultimately recapitulated its beneficial effects on spermatogenesis and steroidogenesis.

Characterizing Endocrine Status, Tumor Hypoxia and Immunogenicity for Therapy Success in Epithelial Ovarian Cancer

Epithelial ovarian cancer is predominantly diagnosed at advanced stages which creates significant therapeutic challenges. As a result, the 5-year survival rate is low. Within ovarian cancer, significant tumor heterogeneity exists, and the tumor microenvironment is diverse. Tumor heterogeneity leads to diversity in therapy response within the tumor, which can lead to resistance or recurrence. Advancements in therapy development and tumor profiling have initiated a shift from a "one-size-fits-all" approach towards precision patient-based therapies. Here, we review aspects of ovarian tumor heterogeneity that facilitate tumorigenesis and contribute to treatment failure. These tumor characteristics should be considered when designing novel therapies or characterizing mechanisms of treatment resistance. Individual patients vary considerably in terms of age, fertility and contraceptive use which innately affects the endocrine milieu in the ovary. Similarly, individual tumors differ significantly in their immune profile, which can impact the efficacy of immunotherapies. Tumor size, presence of malignant ascites and vascular density further alters the tumor microenvironment, creating areas of significant hypoxia that is notorious for increasing tumorigenesis, resistance to standard of care therapies and promoting stemness and metastases. We further expand on strategies aimed at improving oxygenation status in tumors to dampen downstream effects of hypoxia and set the stage for better response to therapy.

Active immunization with GnRH-tandem-dimer peptide in young male rats reduces serum reproductive hormone concentrations, testicular development and spermatogenesis

GnRH sterilization vaccines have been developed for various practical and clinical reasons. However, conjugation of GnRH peptide to carrier protein has many drawbacks, hampering the further commercialization of GnRH vaccines. In this study, a new nonconjugated GnRH vaccine, D-Lys6-GnRH-tandem-dimer peptide (TDK), emulsified in Specol adjuvant was investigated for its immunocastration efficacy in young male rats. Prepubertal male rats were randomly allocated into three groups (n = 12): control (no treatment), surgically castrated or immunized against 100 μg TDK in Specol adjuvant at 6 weeks of age (with a booster 8 weeks later). Blood samples (for antibody titers and hormone concentrations) were collected at 2-week intervals until rats were killed (18 weeks of age). Compared to intact controls, active immunization against TDK reduced (P < 0.05) serum concentrations of testosterone, inhibin B, LH and FSH, prevented the onset of spermatogenesis at puberty. Furthermore, mRNA expressions of GnRH receptor, LH-β and FSH-β in the pituitary, LH receptor, FSH receptor, inhibin α, βA and βB subunit in the testes were decreased in immunocastrated rats compared to intact controls (P < 0.05). These results demonstrate for the first time that GnRH-tandem-dimer peptide emulsified in Specol is a promising veterinary sterilization medicine.

Serum activin-A as a predictive and prognostic marker in critically ill patients with sepsis

BACKGROUND AND OBJECTIVE

There are limited data regarding serum activin-A as a biomarker for sepsis. We examined whether serum activin-A concentration could predict sepsis severity and prognosis in the management of critically ill patients with sepsis.

METHODS

The subjects were adult patients suspected of having sepsis and admitted to intensive care unit (ICU) from January 2013 to March 2014. Serum activin-A concentration was measured in blood sampled within 48 h after ICU admission. The primary and secondary outcomes were the diagnostic value of serum activin-A concentration as a biomarker of sepsis and the prognostic value for predicting the clinical outcomes of sepsis, respectively.

RESULTS

One hundred and thirty patients who had clinically suspected sepsis were included. Most (66.2%) were male; their median age was 65 years, and their Acute Physiology and Chronic Health Evaluation II score was 22.3. Serum activin-A concentration tended to increase with sepsis severity and differed significantly between those with non-sepsis and severe sepsis and between those with severe sepsis and septic shock. The risks of sepsis, severe sepsis and septic shock were significantly higher in patients with a serum activin-A concentration of 251, 319 and 432 pg/mL or greater, respectively. Serum activin-A concentration was significantly associated with the Acute Physiology and Chronic Health Evaluation II score, Sequential Organ Failure Assessment score, Charlson comorbidity index and ICU mortality.

CONCLUSION

Serum activin-A was a predictor of sepsis severity and a prognostic marker in critically ill patients with sepsis. Serum activin-A concentration in the early phase of sepsis was associated with prognostic indexes on ICU admission and with ICU mortality.

Physiologic Course of Female Reproductive Function: A Molecular Look into the Prologue of Life

The genetic, endocrine, and metabolic mechanisms underlying female reproduction are numerous and sophisticated, displaying complex functional evolution throughout a woman's lifetime. This vital course may be systematized in three subsequent stages: prenatal development of ovaries and germ cells up until in utero arrest of follicular growth and the ensuing interim suspension of gonadal function; onset of reproductive maturity through puberty, with reinitiation of both gonadal and adrenal activity; and adult functionality of the ovarian cycle which permits ovulation, a key event in female fertility, and dictates concurrent modifications in the endometrium and other ovarian hormone-sensitive tissues. Indeed, the ultimate goal of this physiologic progression is to achieve ovulation and offer an adequate environment for the installation of gestation, the consummation of female fertility. Strict regulation of these processes is important, as disruptions at any point in this evolution may equate a myriad of endocrine-metabolic disturbances for women and adverse consequences on offspring both during pregnancy and postpartum. This review offers a summary of pivotal aspects concerning the physiologic course of female reproductive function.

Effect of immunization against GnRH on hypothalamic and testicular function in rams

The objective was to determine effects of active immunization against GnRH on reproductive function in Tibetan rams. Peripubertal Tibetan rams (n = 30) were randomly and equally allocated into three groups: control (no treatment); surgically castrated; or immunized against 100-μg d-Lys6-GnRH-tandem-dimer peptide conjugated to ovalbumin in Specol adjuvant at 24 weeks of age (with a booster 8 weeks later). Blood samples (for antibody titers and hormone concentrations) were collected at 4-week intervals until rams were killed (40 weeks). Immunization triggered a good antibody response in all immunized rams (P < 0.01). Compared with intact controls, anti-GnRH immunization reduced (P < 0.01) serum concentrations of testosterone, inhibin A, LH, and FSH, and it induced testicular atrophy (suppression of spermatogenesis). Androstenone concentrations in fat tissues of GnRH-immunized rams were also rendered nondetectable (P < 0.001). Furthermore, mRNA expressions of GnRH receptor, LH-β, and FSH-β in the pituitary and of LH receptor, FSH receptor, and inhibin α and βA subunits in the testes were decreased in immunized rams compared with intact controls (P < 0.05). This was apparently the first report that active immunization against GnRH-tandem-dimer-ovalbumin conjugate in Specol adjuvant was an effective alternative to surgical castration for Tibetan rams under practical Tibetan plateau conditions.

Inhibin at 90: from discovery to clinical application, a historical review

When it was initially discovered in 1923, inhibin was characterized as a hypophysiotropic hormone that acts on pituitary cells to regulate pituitary hormone secretion. Ninety years later, what we know about inhibin stretches far beyond its well-established capacity to inhibit activin signaling and suppress pituitary FSH production. Inhibin is one of the major reproductive hormones involved in the regulation of folliculogenesis and steroidogenesis. Although the physiological role of inhibin as an activin antagonist in other organ systems is not as well defined as it is in the pituitary-gonadal axis, inhibin also modulates biological processes in other organs through paracrine, autocrine, and/or endocrine mechanisms. Inhibin and components of its signaling pathway are expressed in many organs. Diagnostically, inhibin is used for prenatal screening of Down syndrome as part of the quadruple test and as a biochemical marker in the assessment of ovarian reserve. In this review, we provide a comprehensive summary of our current understanding of the biological role of inhibin, its relationship with activin, its signaling mechanisms, and its potential value as a diagnostic marker for reproductive function and pregnancy-associated conditions.

Activin A regulates growth of gastro-intestinal epithelial cells by mediating epithelial-mesenchymal interaction

The importance of epithelial-mesenchymal interaction on the development of gastro-intestinal (GI) organs has been repeatedly reported, but its molecular mechanism has not been fully understood though several factors including hepatocyte growth factor and endothelin-3 have been shown to mediate it. Activins have been demonstrated to play important roles in the regulation of organogenesis in vertebrates, but their roles in the regulation of growth and differentiation of GI organs remain to be solved. In the present study, we examined expression of activins in developing rat GI tract, and found that inhibin bA encoding activin A was specifically expressed by GI mesenchymes, while inhibin bB encoding activin B was expressed by both epithelial and mesenchymal components. We then examined the effect of activin A on the growth of fetal rat GI epithelial cells in primary culture. We found that activin A inhibited the growth of forestomach and glandular stomach epithelial cells while it stimulated the growth of colonic epithelial cells. These results suggest that activin A secreted from GI mesenchymes region-specifically regulates the growth of attaching epithelial cells. We thus conclude that activin A mediates epithelial-mesenchymal interaction in the developing GI tract.

SOT Symposium Highlight: Translatable Indicators of Testicular Toxicity: Inhibin B, MicroRNAs, and Sperm Signatures

Testicular toxicity is an important safety endpoint in drug development and risk assessment, but reliable and translatable biomarkers for predicting injury have eluded researchers. However, this area shows great potential for improvement, with several avenues currently being pursued. This was the topic of a symposium session during the 2013 Society of Toxicology Annual Meeting in San Antonio, TX, entitled "Translatable Indicators of Testicular Toxicity: Inhibin B, MicroRNAs, and Sperm Signatures." This symposium brought together stakeholders from academia, government, and industry to present the limitations and drawbacks of currently used indicators of injury and discussed the ongoing efforts in developing more predictive biomarkers of injury. The presentations highlighted the early challenges of using circulating inhibin B and microRNA levels, and sperm messenger RNA transcript abundance and DNA methylation profiles, as novel biomarkers of testicular toxicity.

The male reproductive system in classic galactosemia: cryptorchidism and low semen volume

Previous studies examining reproductive parameters in men with galactosemia have inconsistently demonstrated abnormalities. We hypothesized that men with galactosemia may demonstrate evidence of reproductive dysfunction. Pubertal history, physical examination, hormone levels and semen analyses were examined in 26 males with galactosemia and compared to those in 46 controls. The prevalence of cryptorchidism was higher in men with galactosemia than in the general population [11.6% vs. 1.0% (95%CI: 0.75-1.26; p <0.001)]. Testosterone (461±125 vs. 532± 33 ng%; p=0.04), inhibin B (144±66 vs. 183±52 pg/mL; p=0.002) and sperm concentration (46±36 vs. 112±75×10(6) spermatozoa/mL; p=0.01) were lower and SHBG was higher (40.7±21.5 vs 26.7±14.6; p=0.002) in men with galactosemia compared to controls. Semen volume was below normal in seven out of 12 men with galactosemia. Men with galactosemia have a higher than expected prevalence of cryptorchidism and low semen volumes. The subtle decrease in testosterone and inhibin B levels and sperm count may indicate mild defects in Sertoli and Leydig cell function, but does not point towards severe infertility causing reproductive impairment. Follow-up studies are needed to further determine the clinical consequences of these abnormalities.

Targeting testis-specific proteins to inhibit spermatogenesis: lesson from endocrine disrupting chemicals

INTRODUCTION

Exposure to endocrine disrupting chemicals (EDCs) has recently been linked to declining fertility in men in both developed and developing countries. Since many EDCs possess intrinsic estrogenic or androgenic activities, thus, the gonad is one of the major targets of EDCs.

AREAS COVERED

For the past 2 decades, studies found in the literature regarding the disruptive effects of these EDCs on reproductive function in human males and also rodents were mostly focused on oxidative stress-induced germ cell apoptosis, disruption of steroidogenesis, abnormal sperm production and disruption of spermatogenesis in particular cell adhesion function and the blood-testis-barrier (BTB) function. Herein, we highlight recent findings in the field illustrating testis-specific proteins are also targets of EDCs.

EXPERT OPINION

This information should be helpful in developing better therapeutic approach to manage ECD-induced reproductive toxicity. This information is also helpful to identify potential targets for male contraceptive development.

Summary of the HESI consortium studies exploring circulating inhibin B as a potential biomarker of testis damage in the rat

The Developmental and Reproductive Toxicity Technical Committee of the Health and Environmental Sciences Institute hosted a working consortium of companies to evaluate a new commercially available analytic assay for Inhibin B in rat serum or plasma. After demonstrating that the kit was stable and robust, the group performed a series of independent pathogenesis studies (23 different compound/investigator combinations) designed to examine the correlation between the appearance of lesions in the testis and changes in circulating levels of Inhibin B. These studies were reported individually in the previous articles in this series (this issue), and are discussed in this paper. For roughly half of these exposures, lesions appeared well before Inhibin B changed. A few of the studies showed a good correlation between seminiferous tubule damage and reduced circulating Inhibin B levels, while for seven exposures, circulating Inhibin B was reduced with no detectable alteration in testis histology. Whether this indicates a prodromal response or a false-positive signal will require further investigation. These exceptions could plausibly suggest some value of circulating Inhibin B as a useful biomarker in some circumstances. However, for roughly half of these exposures, Inhibin B appeared to be a lagging biomarker, requiring significant damage to the seminiferous tubules before a consistent and credible reduction in circulating levels of Inhibin B was observed.