Pituitary-specific Transcription Factor Research Articles

The effect of miR-23b-3p on regulating GH by targeting POU1F1 in Yanbian yellow cattle

This study aimed to evaluate the effect of miR-23b-3p on growth hormone (GH) in pituitary cells of Yanbian yellow cattle. The mRNA and protein levels of GH and miR-23b-3p target genes were measured by real time fluorescence quantitative PCR (qPCR) and Western blot, respectively. The target relationship of miR-23b-3p was validated by double luciferase reporter gene system. The results showed that GH mRNA and protein levels in pituitary cells of Yanbian yellow cattle were significantly lower in the miR-23b-3p-mi group than in the NC group (P<0.01), while GH mRNA and protein levels were higher in the miR-23b-3p-in group than in the iNC group (P<0.05). The result of bioinformatics analysis and double luciferase reporter gene system validation proved that miR-23b-3p targeted 3′UTR of pituitary specific transcription factor 1 (POU1F1). POU1F1 mRNA and protein levels were lower miR-23b-3p-mi group than in the NC group (P<0.01), while POU1F1 mRNA and protein levels were higher in the miR-23b-3p-in group than in the iNC group (P<0.01). These results demonstrated that miR-23b-3p could regulate GH expression in pituitary cells by regulating POU1F1 gene.

Identification of some genetic markers as productive and reproductive traits in Ukrainian dairy cattle breeding

A Selection based on DNA markers is a breeding technique grounded in the genomic selection value of animals. The aim of the research is to study the genotypic profile of cows of different breeds in Ukrainian breeding in relation to the genes LEP, CSN3, TG5, BLG, and Pit-1 and to identify the probability of using them as markers for reproductive traits in cows. During the study, the Polymerase Chain Reaction-Restriction Fragment Length Polymorphism (PCR-RFLP) method was used to analyze the genes and determine their polymorphic characteristics. The obtained data indicated that the same gene variants have varying effects in the studied breeds due to their diverse influences on the genomic background. Specifically, the homozygous state of leptin genes (LEPCC) and pituitary-specific transcription factor (PIT-1BB) was observed to impact the reproductive characteristics of cows in the evaluated breeds. Meanwhile, for the genes casein (CSN3AB), thyroglobulin (TG5CT), and beta-lactoglobulin (BLGAВ), the heterozygous state of alleles was found to influence the key reproductive traits of dairy cattle of Holstein origin. The polymorphism of the genes CSN3, βLG, TG, PIT-1, and LEP indicated the presence of genetic potential for the reproductive function of cows and can be utilized as molecular markers in selective breeding, providing significant progress in improving not only the traits of dairy cattle productivity but also reproductive function. Therefore, in the implementation of selective breeding work, it is advisable to consider genotyping for the genes CSN3, βLG, TG, PIT-1, and LEP as an additional criterion for the selection of animals to enhance both their milk and reproductive characteristics.

ПОРОДНІ ОСОБЛИВОСТІ АЛЕЛЬНОГО ПРОФІЛЮ ГЕНІВ PIT1 ТА GH УКРАЇНСЬКОЇ АБОРИГЕННОЇ ЛЕБЕДИНСЬКОЇ ПОРОДИ КОРІВ

The preservation of genetic diversity is a paramount concern in addressing global challenges today. The foundation of biological diversity hinges on its genetic components, and the loss of species and genetic variability poses a genuine threat to the biosphere. This is because the sustainability of natural ecosystems and agroecosystems depends directly on their genetic adaptability to changing environmental conditions.&#x0D; In cattle, genes associated with milk yield play a crucial role, including genes related to milk proteins and hormones. Among these, the pituitary-specific transcription factor (PIT1) and growth hormone (GH) genes are of particular significance. In this study, we investigated the polymorphism of these genes in the Lebedyn breed of cattle.&#x0D; A total of 2 gene polymorphisms, PIT1 and GH, were examined through molecular and genetic research conducted at the genetics laboratory of the Institute of Animal Breeding and Genetics named after M. V. Zubets, part of the National Academy of Agrarian Science of Ukraine. The study utilized 32 DNA samples extracted from the venous blood of Lebedyn breed cows using the 'DNA Sorb-B' kit from AmpliSens. Genotyping was carried out through polymerase chain reaction (PCR-RFLP) analysis of restriction fragment length polymorphism, employing the “Tertsyk” amplifier for PCR. The resulting DNA restriction analysis products were assessed via electrophoresis in a 2–3% agarose gel containing ethidium bromide, with DNA fragment lengths determined using the GeneRuler TM 50 bp DNA Ladder and Thermo Scientific™ GeneRuler 1 kb Plus DNA Ladder markers.&#x0D; For the PIT1 gene analysis, a 451 bp amplified fragment was treated with the enzyme HinfI, yielding the following allele frequencies: A (0.38) and B (0.62). The heterozygous AB genotype was the most prevalent (0.45), while homozygotes for the A allele constituted 0.15 of the population. In the case of the GH gene fragment (223 bp), hydrolysis was performed using the restriction enzyme AluI. Analysis of allele frequency distribution indicated a high frequency of the L allele (0.85), with no animals exhibiting the homozygous GHVV genotype, and the GHLL genotype was present in 0.7 of the population.&#x0D; These findings reveal unique features of the allelic spectrum of the PIT1 (V-0.62) and GH (L-0.85) genes specific to the Ukrainian indigenous Lebedyn breed of cows. Selectionally significant genotypes include PIT1AA (15%) and GHLL (70%), while heterozygote carriers, which contribute to genetic diversity within the population, account for 45% and 30%, respectively.&#x0D; This study’s results hold particular value due to the alarming decline in the population of local indigenous breeds and the imminent threat to the preservation of agricultural genetic resources.

THU084 Corticotroph Tumor Type Influences Clinical Presentation In Patients With Nonfunctioning Pituitary Neuroendocrine Tumors

Abstract Disclosure: N. Al-Shamkhi: None. B. Edén Engström: None. O. Gudjonsson: None. J. Wikström: None. O. Casar-Borota: None. E. Rask: None. Introduction: According to the current World Health Organization classification of endocrine tumors the classification of non-functioning pituitary neuroendocrine tumors (NF-PitNET) is based on pituitary cell lineages, defined by immunohistochemical expression of anterior pituitary hormones and pituitary specific transcription factors. The second most common NF-PitNET type, after silent gonadotroph tumors, are silent corticotroph tumors that are regarded as a potentially more aggressive type. If there is indication for treatment, the first-line treatment is transsphenoidal surgery. Some, but not all studies have shown a higher degree of preoperative pituitary failure or more frequent postoperative pituitary failure in patients with silent corticotroph tumors compared to the other NF-PitNET. Objectives: We compared patients with silent corticotroph and silent gonadotroph tumors, and explored whether tumor type and radiological findings were associated with pre- or postoperative pituitary failure. Design and method: One hundred patients who underwent surgery for NF-PitNET at the same tertiary center were included. Data regarding age at surgery, sex, pre- and postoperative pituitary function and tumor type, were collected after chart review. Preoperative MRI examinations were revised regarding tumor volume and Knosp classification. Results: The majority, 72% (72/100) were classified as silent gonadotroph tumors followed by 18% (18/100) silent corticotroph tumors. Patients with silent corticotroph tumors were younger at surgery, P=0.003. There were no differences regarding sex, preoperative tumor volume, invasive growth on MRI, defined as Knosp grade &amp;gt; 3, pituitary failure or prolactin elevation between the two tumor types. Binary logistic regression showed that having a silent corticotroph tumor, P=0.04, odds ratio 5.7 (CI: 1.06-30.71), higher age at surgery, P=0.003, odds ratio 1.07 (CI: 1.02-1.13), and a larger preoperative tumor volume, P=0.01, odds ratio 1.18 (CI: 1.04-1.33), were all factors associated with an increased likelihood of having postoperative pituitary failure. Sex, invasive growth and preoperative prolactin elevation were not significant predictors of postoperative pituitary failure in the binary logistic regression. Conclusion: The results indicate that silent corticotroph tumors influence the clinical presentation of NF-PitNET. Patients with silent corticotroph tumors were significantly younger at surgery, and demonstrated an increased likelihood of postoperative pituitary failure. Presentation: Thursday, June 15, 2023

Digital image analysis allows objective stratification of patients with silent PIT1-lineage pituitary neuroendocrine tumors.

Studies describing the clinical presentation and prognosis of patients with silent PIT1 (pituitary specific transcription factor)-lineage pituitary neuroendocrine tumors (PitNETs) are rare. We identified patients with positive PIT1 tumor staining but without evidence of hormone hypersecretion at a tertiary center. Clusters were obtained according to cell morphology and immunostaining from each patient's digitally segmented whole slide image. We compared the clinical presentations, radiological features, and prognoses of the different clusters. We identified 146 patients (68 male, 42.9 ± 14.1 years old) with silent PIT1-lineage PitNETs. Morphology clustering suggested that tumors with large nuclei and apparent eccentricity were associated with a higher proportion of aggressiveness and a higher hazard of recurrence [hazard ratio (HR): 2.64, (95% CI, 1.06-6.55), p = 0.037]. Immunohistochemical clustering suggested that tumors with thyroid stimulating hormone (TSH) staining or all negative PIT1-lineage hormones were associated with a higher proportion of aggressiveness and a higher risk of recurrence [HR: 12.4, (95% CI, 1.60-93.5), p = 0.015]. We obtained three-tier risk profiles by combining morphological and immunohistochemical clustering. Patients with the high-risk profile presented the highest recurrence rate compared with those in the medium-risk and low-risk profiles [HR: 3.54, (95% CI, 1.40-8.93), p = 0.002]. In conclusion, digital image analysis based on cell morphology and immunohistochemical staining allows objective stratification of patients with silent PIT1-lineage tumors. Typical morphological characteristics of high-risk tumors are large tumor nuclei and high eccentricity, and typical immunostaining characteristics are TSH staining or negative staining for all PIT1-lineage hormones.

Transcription Factor Immunohistochemistry in the Classification of Pituitary Neuroendocrine Tumor/Adenoma: Proposal in a Limited-Resource Setting.

Pituitary neuroendocrine tumors/adenomas are common intracranial tumors that require accurate subtyping because each tumor differs in its biologic behavior and response to treatment. Pituitary-specific transcription factors allow for improved lineage identification and diagnosis of newly introduced variants. To assess the usefulness of transcription factors and design a limited panel of immunostains for classification of pituitary neuroendocrine tumors/adenoma. A total of 356 tumors were classified as per expression of pituitary hormones and transcription factors T-box family member TBX19 (TPIT), pituitary-specific POU-class homeodomain (PIT1), and steroidogenic factor-1 (SF-1). The resultant classification was correlated with patients' clinical and biochemical features. The performance and relevance of individual immunostains were analyzed. Reclassification of 34.8% (124 of 356) of pituitary neuroendocrine tumors/adenoma was done after application of transcription factors. The highest agreement with final diagnosis was seen using a combination of hormone and transcription factors. SF-1 had higher sensitivity, specificity, and predictive value compared with follicle-stimulating hormone and luteinizing hormone. On the other hand, TPIT and PIT1 had similar performance and Allred scores compared with their respective hormones. SF-1 and PIT1 should be included in the routine panel for guiding the classification. PIT1 positivity needs to be followed by hormone immunohistochemistry, especially in nonfunctional cases. TPIT and adrenocorticotropin can be used interchangeably as per availability of the lab.

The study of the strength and significance of four biological parameters on the body weight of goose.

Alternative products such as those from high-value protien animals have increased the demand for the production of high-quality chicken meat in past few years. This study examines the impact of two distinct feeding types on goose body-weight, as well as the genetic variation of growth hormone (GH) and pituitary-specific transcription factor (Pit-1) genes in ten goose populations using single nucleotide polymorphism (SNP) markers and PCR-RFLP analysis. Both genes were seen as very important for productivity, especially in light of the COVID-19 and its effect on poultry industry at the time. The findings suggest that employing genetic indicators in these two genes in conjunction with a high-fat diet may be a feasible strategy for goose selection programme aiming to increase marketing body weight, as the high-fat diet outperformed the balanced diet. The study investigates the effect of gender, 2 types of diets, breeds and the genetic variation of the two genes, four SNPs were reported to be found: two at the GH gene exons C123T and C158T, and two at the Pit-1 gene exons G161A and T282G. Certain genotypes were found to have a substantial effect on the marketing body-weight of goose, which varied depending on the tested breeds. However, in terms of gender, males report higher and better performance levels than females. Diet, breeds and genotype interaction, and breeds, gender and genotype interaction were found to have a minor effect on goose body weight. However, diet, breeds, gender, SNP locus, diet and breeds interaction, and breeds and gender interaction were found to have a significant effect on goose body weight, as indicated by the effect size results.

A new insight into GH regulation and its disturbance from nutrition and autoimmune perspectives.

GH activates GH receptors, which activates IGF-1 in the liver through a cascade of processes. The GH/IGF-1 axis plays an important role in the regulation of metabolism. Insufficient GH secretion results in short stature in childhood, while adult GH deficiency (AGHD) is observed in adulthood. The early diagnosis of AGHD is important for early initiation of GH replacement therapy. This review described the regulatory mechanisms of GH signaling based on nutritional status and a novel disease concept pathogenesis that causes AGHD. GH-dependent IGF-1 production in the liver is regulated by a complex interplay between nutritional status, hormones, and growth factors. GH resistance is an adaptive response that enhances survival during starvation and malnutrition. Sirtuin 1 (SIRT1) negatively regulates GH-induced IGF-I production in the liver by directly inhibiting STAT5 activation, which causes GH resistance under starvation and malnutrition. The presence of autoantibodies is strongly associated with the disruption of immune tolerance in pituitary cells. Pituitary-specific transcription factors (PIT-1) are essential for the development, differentiation, and maintenance of GH, PRL, and TSH producing cells. However, the underlying mechanism that causes immune intolerance to PIT-1 remain unclear. The GH-IGF-1 system plays a pivotal role in growth, and the involvement of SIRT1 in this regulatory mechanism presents an intriguing perspective on the interplay between nutrient metabolism and lifespan. The discovery of the anti-PIT-1 pituitary antibody, a novel disease concept associated with AGHD, has provided valuable insights, which serves as a significant milestone towards unraveling the complete pathogenesis of the disease.

Identification of Pituitary-Specific Transcription Factor-1 (PIT-1) Genotype in Bali Cattle

This study aimed to identify the genotype of the gene Pituitary-specific transcription factor 1 (Pit-1) in Bali cattle (Bos sondaicus). A total of 20 cows Bali (13 males and 7 females) were used in this study. DNA samples isolated from blood samples using phenol-chloroform extraction method (Sambrook et al., 1989). This study using PCR-RFLP method. Amplification of specific DNA fragments (size 451 bp, intron regions stretching from 4 to exon 6) of the Pit-1 gene Bali cattle samples was performed using a pair of specific primers (forward: 5'-AAA-CCA-TCA-TCT-CCC-TTC-TT -3 ', and reverse: 5'-AAT-GTA-CAA-TGT-GCC-TTC-TGA-G-3'). Based on the results of RFLP analysis/HinfI was found that all of Bali cattle research resulted banding pattern uniform (monomorphic), the band size 244 bp and 207 bp, and the band patterns thus identified as genotype BB, so it is known that the frequency of A and B alleles at 0 and 1. The frequency of A allele was not found in Bali cattle (Bos sondaicus) showed a significant difference with other cattle breeds (Bos taurus and Bos indicus).

Additive and Dominance Effects of MC4R and PIT1 Polymorphisms on Production and Carcass Traits in Duroc Pigs

This study aimed to estimate the allelic and genotypic frequencies of single nucleotide polymorphisms (SNPs) of MC4R (melanocortin-4-receptor gene) and PIT1 (pituitary specific transcription factor-1) genes, and their additive dominance genetic effects on production and carcass traits in Duroc pigs. A total of 2170 tail tissue samples (1728 gilts and 442 male pigs) were collected from Dabaco Nucleus Breeding Pig Company, Bac Ninh province, Vietnam from January 2017 to June 2020. Polymorphisms in the MC4R and PIT1 genes were detected using the PCR-RFLP method. For MC4R, the frequencies of alleles A and G were 0.430 and 0.570, respectively. For PIT1, the frequencies of alleles A and B were 0.460 and 0.540, respectively. The genotype frequency distribution of the MC4R gene was in Hardy-Weinberg equilibrium (P = 0.375), but the genotype frequency distribution of PIT1 (P &lt;0.001) was not. The MC4R and PIT1 polymorphisms were significantly associated with final body weight and average daily gain (P &lt;0.001). Significant additive effects were also found (P &lt;0.05) for the two traits. The selection of individuals with the MC4R genotype AA and PIT1 genotype AA could improve final body weight and average daily gain in Duroc pigs.

Association of polymorphisms in lipid and energy metabolism-related genes with fattening performance in Simmental cattle

Lipid and energy metabolism are major constituents of mammal growth and thus fattening performance of cattle. This study was designed to evaluate the effects of polymorphisms in lipid and energy metabolism-related genes including oxidized low-density lipoprotein receptor 1 (OLR1), lactoferrin (LTF), stearoyl-CoA desaturase (SCD), beta-lactoglobulin (LGB), thyroglobulin (TG), annexin A9 (ANXA9), myogenic factor 5 (MYF5), protein kinase AMP-activated non-catalytic subunit gamma 3 (PRKAG3), and pituitary-specific transcriptional factor 1 (PIT1), on fattening performance in Simmental cattle. A total of 72 purebred Simmental bulls with a similar initial age and weight were fattened on the same farm for 10 months. Association analysis was performed using linear mixed models. The OLR1 marker was significantly associated with the final weight (FW), hot carcass weight (HCW), chilled carcass weight (CCW), dressing percentage (DP), and total weight gain (TWG). SCD affected the FW, TWG, and average daily live weight gain (ADWG). The present results clearly demonstrated the significant impact of the TG marker on fattening performance. It was highly significantly associated with the FW, HCW, CCW, and TWG. The SCD × TG and the OLR1 × TG interactions had remarkable effects on the traits analyzed. The GACC and CCCC haplotypes of the SCD × TG and OLR1 × TG, respectively, were found to be powerful markers for fattening performance in Simmentals. Novel associations in this study may be useful for further genetic evaluations to improve beef cattle breeding.

POU1F1/Pou1f1 c.143-83A > G Variant Disrupts the Branch Site in Pre-mRNA and Leads to Dwarfism.

POU Class 1 Homeobox1 (POU1F1/Pou1f1) is a well-established pituitary-specific transcription factor, and causes, when mutated, combined pituitary hormone deficiency in humans and mice. POU1F1/Pou1f1 has 2 isoforms: the alpha and beta isoforms. Recently, pathogenic variants in the unique coding region of the beta isoform (beta domain) and the intron near the exon-intron boundary for the beta domain were reported, although their functional consequences remain obscure. In this study, we generated mice carrying the Pou1f1 c.143-83A>G substitution that recapitulates the human intronic variant near the exon-intron boundary for the beta domain. Homozygous mice showed postnatal growth failure, with an average body weight that was 35% of wild-type littermates at 12 weeks, which was accompanied by anterior pituitary hypoplasia and deficiency of circulating insulin-like growth factor 1 and thyroxine. The results of RNA-seq analysis of the pituitary gland were consistent with reduction of somatotrophs, and this was confirmed immunohistochemically. Reverse transcription polymerase chain reaction of pituitary Pou1f1 mRNA showed abnormal splicing in homozygous mice, with a decrease in the alpha isoform, an increase in the beta isoform, and the emergence of the exon-skipped transcript. We further characterized artificial variants in or near the beta domain, which were candidate positions of the branch site in pre-mRNA, using cultured cell-basis analysis and found that only c.143-83A>G produced transcripts similar to the mice model. Our report is the first to show that the c.143-83A>G variant leads to splicing disruption and causes morphological and functional abnormalities in the pituitary gland. Furthermore, our mice will contribute understanding the role of POU1F1/Pou1f1 transcripts in pituitary development.

ODP359 Thyrotropin secreting pituitary microadenoma and lung adenocarcinoma treated with epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitors (TKIs) Erlotinib and Osimertinib: a case report

Abstract Background Thyrotropin secreting pituitary adenoma (TSHoma) of the pituitary specific transcription factor-1 (PIT-1) lineage, is the rarest subtype of pituitary neuroendocrine tumours (pitNETs). TSHomas must be discriminated from primary hyperthyroidism and can cause morbidity through thyrotoxicosis or local mass effect. Serum alpha-subunit level may be used as a marker of tumour activity, as 50-85% of TSHoma patients have high serum alpha-subunit levels. First line treatment is surgical resection of the tumour. Medical therapy with somatostatin analogues or radiotherapy may be used for tumour control. Epidermal growth factor receptor (EGFR) expression has been demonstrated in pitNETs including corticotrophs, gonadotrophs, lactotrophs and somatotrophs. EGFR inhibiting agent, Lapatinib, has been investigated for treatment of prolactinomas and EGFR expression is implicated in tumorigenesis of corticotrophs. EGFR targeting tyrosine kinase inhibitors (TKIs) can be used first line to treat metastatic adenocarcinoma of the lung harbouring activating EGFR mutations. Case Report A non-smoking 53-year-old male of Middle Eastern heritage was seen in clinic with secondary hyperthyroidism on a background of metastatic adenocarcinoma of the lung and hypertension. The patient had no symptoms of hyperthyroidism and had no personal or family history of thyroid dysfunction. No new headaches or visual disturbance were reported. Physical exam showed brisk reflexes, no specific signs of hyperthyroidism or thyromegaly were seen. Thyroid function tests demonstrated a persistently elevated TSH 5.1mIU/L (0.4-4. 0), T4 21.8pmol/L (9-19) and T3 6.4pmol/L (2.6-6. 0) with negative anti- thyroid receptor, thyroperoxidase and thyroglobulin antibodies. Ultrasound of the thyroid was unremarkable. MRI revealed a well-circumscribed left anterior pituitary lesion of 5.4×6.8mm in size. Surgery was deferred as 3 months prior, he was diagnosed with stage 4 intrapulmonary adenocarcinoma of the lung with an exon-19 deletion mutation in the EGFR gene. He received stereotactic radiotherapy and EGFR targeted therapy using 100mg of Erlotinib daily, which increased to 200mg 6 months later. After 1 year of therapy, his adenocarcinoma progressed and he was transitioned to the 3 rd generation EGFR-TKI Osimertinib. Instead of undergoing the risk of pituitary surgery, a trial of EGFR therapy for its pleiotropic pituitary adenoma effects was decided. During the EGFR-TKI treatment period, alpha subunit levels have remained stable and serial MRI imaging at 1 year showed no interval pituitary adenoma growth. Conclusion This is a rare case of TSHoma identified during treatment of lung cancer with EGFR-TKIs. EGFR signalling is implicated in prolactinomas and corticotrophs though there is a paucity of data regarding TSHomas. To date, our patient has achieved radiological and biochemical stability in his TSHoma, with hyperthyroidism control on EGFR-TKI therapy, suggestive of a therapeutic benefit from EGFR signal blockade. Further studies are needed in larger cohorts to quantify EGFR expression in TSHomas and evaluate its possible role in pathogenesis. Presentation: No date and time listed

PMON145 The Role of Pou3f4 in Pituitary Development and Disease

Abstract Mutations in the pituitary specific transcription factor Prophet of Pit-1 (PROP1) are the most common genetic etiology of combined pituitary hormone deficiency (CPHD), which affects 1 in 8,000 newborns worldwide. CPHD is associated with short stature, attributable to growth hormone (GH) deficiency and/or thyroid stimulating hormone (TSH) deficiency. Pathogenic lesions impair pituitary development and differentiation of endocrine cells. Prop1-mutant mice show increased expression of genes including SRY-Box Transcription Factor 21 (Sox21) and Pou Domain, Class 3, Transcription Factor 4 (Pou3f4). POU3F4 is expressed in the developing inner ear and restricts the proliferation and lineage potential of neural stem cells. Genetic defects cause non-syndromic X-linked deafness (DFNX2) in humans and mice. The function of POU3F4 in pituitary development is largely unknown and the implications of its overexpression in Prop1-mutant pituitaries remain unexplored. Therefore, we aim to address the role of Pou3f4 in pituitary development and determine the contributions of Pou3f4 upregulation to pituitary disease by utilizing Pou3f4-mutant mice as well as double mutant mice lacking both Prop1 and Pou3f4. Utilizing immunofluorescent analysis at critical timepoints during pituitary development, we have characterized the timeline for endogenous POU3F4 expression. Initial expression is detected at e11.5 in differentiating cells on the ventral side of Rathke's pouch and is restricted to the proliferating anterior lobe at e13.5, continuing postnatally, similar to previously published expression data. POU3F4 expression then decreases and becomes gradually restricted to the periluminal stem cell niche at e15.5 and p0. We further validated the upregulation of POU3F4 in histological sections of Prop1-mutant mice at e15 and p0, finding increased expression in the developing anterior lobe of mutants compared to wildtypes. Single-cell regulatory network inference and clustering (SCENIC) analyses, which utilize single-cell transcription factor co-expression with potential direct downstream targets that contain the corresponding transcription factors’ binding sequence to infer active transcription networks, predict increased activity of the Pou3f4 gene regulatory network in a subpopulation of Sox2-expressing stem cells in Prop1-mutant mice. Preliminary analyses indicate that Pou3f4 mutant have normal morphology at P1, together with grossly normal expression of Sox2 and Pou1f1. We are performing quantitative PCR to determine possible compensatory mechanisms in response to loss of Pou3f4 expression. To investigate whether any Prop1-mutant phenotypes, including dysmorphology and ectopic expression of Sox21 and Otog, are attributable to Pou3f4 upregulation, we are studying Pou3f4;Prop1 mice. We will determine the impacts of POU3F4 upregulation on cellular morphology, stem cell maintenance and endocrine cell differentiation. The mechanisms of action in the regulation of stem cell differentiation constitutes a gap in our current understanding of the pathogenesis of CPHD. These studies will provide novel insights into the mechanistic function of Pou3f4 during embryonic pituitary development and potential novel etiologies of CPHD in human patients. Presentation: Monday, June 13, 2022 12:30 p.m. - 2:30 p.m.

ODP529 Update on the Prevalence and Pathogenesis of Central Hypothyroidism

Abstract Background Central hypothyroidism (CH) is a rare form of hypothyroidism characterized by insufficient stimulation of a normal thyroid gland by the thyroid-stimulating hormone (TSH). It can be of pituitary origin (secondary hypothyroidism) or hypothalamic origin (tertiary hypothyroidism). The diagnosis is suspected by the finding of low serum free thyroxine associated with low, normal, or slightly elevated serum TSH, in the absence of goiter. This review presents an update on the prevalence and pathogenesis of different types of CH. Methods A systematic search of literature was conducted using the search terms hypothyroidism, central hypothyroidism, congenital central hypothyroidism, acquired central hypothyroidism, TSH deficiency, prevalence, and pathogenesis. Results The prevalence of overt hypothyroidism in the US population is at least 0.3% and the prevalence of subclinical hypothyroidism ranges from 4% to 10%. Primary hypothyroidism is more prevalent in females. The prevalence of CH ranges from 1: 13,000 to 1: 120,000. CH is observed in less than 1% of hypothyroid subjects, with no evidence of sex predominance. Itcan occur prenatally (congenital CH) or after birth (acquired CH). Congenital CH, which is a rare cause of CH (prevalence around 1: 13,000), may result from genetic/malformative causes [e. g., pituitary-specific transcription factor defects, TSH-beta subunit gene mutations, isolated TSH-releasing hormone (TRH) deficiency, TRH receptor gene mutation, immunoglobulin superfamily member 1 deficiency, De Morsier syndrome, Prader Willi syndrome]. In 60% of the cases, congenital CH is associated with other pituitary hormone deficiencies and in 40% of the cases, congenital CH is due to isolated TSH deficiency. Acquired CH, which is the most common cause of CH andusually associated with other pituitary hormone deficiencies, results from the destruction or inhibition of the pituitary and/or hypothalamus. In decreasing order of frequency, acquired CH can be secondary to invasive and/or compressive lesions (e. g., pituitary macroadenomas, craniopharyngiomas, pituitary metastases, carotid aneurysm), iatrogenic factors (e. g., surgery or irradiation, glucocorticoids, dopaminergic drugs, somatostatin analogs, immune checkpoint inhibitors), trauma (e. g., brain injury), vascular causes (e. g., pituitary apoplexy, postpartum pituitary necrosis, hemorrhage), autoimmunity (e. g., lymphocytic hypophysitis), infiltrative lesions (e. g., hemochromatosis, sarcoidosis), and infections (e. g., tuberculosis, syphilis). Conclusion CH is a rare cause of hypothyroidism resulting from a variety of congenital or acquired causes. Acquired CH is the most common cause of CH. In many cases, both congenital and acquired CH are associated with multiple pituitary hormone deficiencies. Isolated TSH deficiency is rare and usually of congenital origin. Presentation: No date and time listed

RF01 | PMON46 Regulation of the Pituitary Cell Lineage Regulator Prop1 by the Stem Cell Determinant Musashi

Abstract The pituitary gland controls responses to changing physiological requirements during growth, pregnancy, puberty, and stress. Synthesis and secretion of appropriate pituitary hormones in response to changing organismal demands is mediated through a remarkable capacity for cellular plasticity of the distinct hormone-producing cells. The mechanisms governing pituitary cellular plasticity are not fully understood. We hypothesize that plasticity in the adult tissue is mediated through similar mechanisms to those that occur during embryonic and postnatal pituitary development. The Prophet of Pit1(Prop1), a paired-like homeodomain transcription factor, is the earliest pituitary-specific transcription factor and is highly expressed in pituitary progenitor cells where it controls lineage commitment to the distinct hormone-producing cell types. Our recent work has identified post-transcriptional regulation of pituitary gene expression in the adult tissue via the stem cell determinant, mRNA binding protein, Musashi. The full-length mouse Prop1 (mProp1) mRNA 3' untranslated region (UTR) contains 24 consensus binding elements for Musashi (MBEs) and demonstrates Musashi1-dependent translational activation in vitro. Specifically, the terminal mProp1 3' UTR MBE directs 40% of Musashi1-mediated translation activation, and mutational disruption of this terminal MBE abolishes all Musashi1-dependent translational activation. Immunoprecipitation of Musashi-mRNA complexes from adult mouse pituitaries confirmed Musashi1-mProp1 mRNA association in adult tissue. The gene sequence data for the human Prop1 (hPROP1) mRNA 3' UTR is incomplete in the Ensembl and RefSeq databases. Using published RNA sequencing datasets, we identified an expressed full-length hPROP1 mRNA 3' UTR of 6996 nucleotides with 54 predicted consensus MBEs, suggesting that the human PROP1 mRNA, like the murine Prop1 mRNA, may be subject to Musashi-dependent translational control. Our findings are consistent with the hypothesis that the Musashi protein exerts evolutionarily conserved control of Prop1 mRNA translation to facilitate plasticity of anterior pituitary function. Presentation: Saturday, June 11, 2022 1:31 p.m. - 1:36 p.m., Monday, June 13, 2022 12:30 p.m. - 2:30 p.m.

Contribution of PROP1 in the pathogenesis of Cushing’s disease: A preliminary study

Prophet of Pit1 (PROP1) is the pituitary specific transcription factor which was cloned as an upstream regulator of PIT1. Cushing’s disease is caused by corticotroph adenomas which does not belong to the PIT1 lineage. The aim of this study was to elucidate the involvement of PROP1 in the pathogenesis of Cushing’s disease. Since it is difficult to accurately evaluate PROP1 expression in pituitary adenomas by RT-PCR analysis due to the inevitable contamination of surgical tissue specimens with normal pituitary cells, we examined six corticotroph adenomas by immunohistochemistry. Adenomas were classified into 2 subtypes based on their staining patterns of CAM5.2: diffuse and non-diffuse types. It is likely that diffuse-type adenomas are composed of more differentiated tumor cells. PROP1 was positive in all three cases of non-diffuse-type adenomas, but negative in all three cases of diffuse-type adenomas, suggesting that PROP1 was prominently expressed in less differentiated non-PIT1 lineage corticotroph adenomas. This study is the first report to analyze PROP1 expression in pituitary adenomas by immunohistochemistry. PROP1 may have a role in tumorigenesis of pituitary adenomas in Cushing’s disease, and is expected to be a new therapeutic target for refractory pituitary adenomas.

Connection between gene markers with milk production traits of Ukrainian dairy cows

The purpose of this study was to obtain information on the genotyping of cows of Ukrainian dairy breeds for the presented loci capa-casein gene (CSN3), thyroglobulin (TG-5) gene, leptin (LEP), pituitary-specific transcription factor (Pit-1), and beta-lactoglobulin (BLG) by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and to test their association with milk production. The influence of the genotype on milk yield, fat and protein content in the milk of cows of Ukrainian selection has been established. The highest levels of milk productivity traits were expected from animals with the CT genotype for the LEP gene, AA for the CSN3 gene, CC for the TG5 gene, and AA and BB for the Pit-1 gene. But at the same time, milk obtained from cows with CSN3 BB genotype were characterized by the best cheese suitability. The effect of the homo- or heterozygous state of BLG on the signs of milk production was less noticeable, and the homozygous TT genotype for the TG5 gene was not found in any of the studied breeds. The results obtained can be used in the practical work of breeding farms along with traditional methods of selection, control and preservation of the genetic diversity of specific herds at an optimal level.

Editorial introductions

Editorial introductions

Prediction of Higher Ki-67 Index in Pituitary Adenomas by Pre- and Intra-Operative Clinical Characteristics.

Objective: The Ki-67 index is an indicator of the active proliferation and aggressive behavior of pituitary adenomas (PAs). Appropriate pre- and intra-operatives of the Ki-67 index can help surgeons develop better and more personalized treatment strategies for patients with PAs. This study aimed to investigate the influence factors for predicting the Ki-67 index in PAs. Methods: Data of 178 patients with PAs confirmed by pathology were retrospectively analyzed. According to the Ki-67 index, the patients were divided into the Ki-67 < 3% and Ki-67 ≥ 3% cohorts. Patient data, including age, sex, postoperative immunohistochemical pituitary hormone positive index, Knosp grade, tumor breaking through the sellar floor, rich blood supply to the tumor, tumor located inside the sella, erosion of the dorsum sellae bone, and pituitary-specific transcription factor, were collected. A univariate logistic analysis was used to evaluate the influence factors for a high Ki-67 index. Multiple regression and receiver operating characteristic (ROC) curve were used to analyze the factors with p < 0.05. The mutant status of Ki-67 index was predicted by nomogram. Results: Multivariate regression analysis showed that rich blood supply to the tumor and erosion of the dorsum sellae bone were independent risk factors for the Ki-67 proliferation index. The ROC curves demonstrated that age, rich blood supply to the tumor, and erosion of the dorsum sellae bone can predict the occurrence of a high Ki-67 index. Together, the three risk factors provide a stronger ability to predict the Ki-67 index. The nomogram was developed and validated. Conclusion: Age, rich blood supply to the tumor, and erosion of the dorsum sellae bone are influencing factors for predicting the Ki-67 index. Suitable nomogram prediction models were developed and validated, and there is potential for personalized treatment for PA patients.