Aggressive pituitary tumors in the young and elderly

Identification of HSPD1 as a novel invasive biomarker associated with mitophagy in pituitary adenomas

BACKGROUND

The crucial role of mitophagy in tumor progression has been recognized. Therefore, our study aimed to investigate the potential correlation between pituitary adenoma invasiveness and the mitophagy processes.

METHODS

In this study, we used transcriptomics of postoperative tissue from 32 patients and quantitative proteomics of 19 patients to screen for mitophagy-related invasion genes in pituitary adenomas. The invasive predictive value of target genes was analyzed by Lasso regression model, CytoHubba plugin and expression validation. Co-expression correlation analysis was used to identify paired proteins for target genes, and a predictive model for pituitary adenoma invasiveness was constructed by target genes and paired proteins and assessed using ROC analysis, calibration curves and DCA. GO function, pathway (GSEA or GSVA) and immune cell analysis (ssGSEA or CIBERSORT) were further utilized to explore the action mechanism of target gene. Finally, immunohistochemistry and cell function experiments were used to detect the differential expression and key roles of the target genes in pituitary adenomas.

RESULTS

Finally, Heat shock protein family D member 1 (HSPD1) was identified as a target gene. The quality of a predictive model for pituitary adenoma invasiveness consisting of HSPD1 and its paired protein expression profiles was satisfactory. Moreover, the expression of HSPD1 was significantly lower in invasive pituitary adenomas than in non-invasive pituitary adenomas. Downregulation of HSPD1 may be significantly related to invasion process, mitochondria-related pathway and immune cell regulation in pituitary adenomas.

CONCLUSION

The downregulation of HSPD1 may serve as a predictive indicator for identifying invasive pituitary adenomas.

Phosphorylation of PBK at Thr9 by CDK5 correlates with invasion of prolactinomas

CONTEXT

Prolactinomas are the most prevalent functional pituitary neuroendocrine tumors (PitNETs), and they are invasive to surrounding anatomic structures. The detailed mechanisms of invasion are not yet clear.

OBJECTIVE

We explored the role of PBK phosphorylation in the proliferation and invasion of prolactinomas and its possible mechanism.

RESULTS

We report that PBK directly binds to and is phosphorylated at Thr9 by cyclin-dependent kinase 5 (CDK5), which promotes GH3 cell EMT progression and proliferation. Phosphorylation of PBK at Thr9 (pPBK-T9) by CDK5 enhances the stability of PBK. p38 is one of the downstream targets of PBK, and its phosphorylation is reduced as pPBK-T9 increases in vivo and in vitro. Furthermore, we found that pPBK-T9 is highly expressed in invasive PitNETs and was significantly correlated with invasion by univariate and multivariate analyses.

CONCLUSIONS

Phosphorylation of PBK at Thr9 by CDK5 promotes cell proliferation and EMT progression in prolactinomas.

Diagnosis and management of prolactin-secreting pituitary adenomas: a Pituitary Society international Consensus Statement

This Consensus Statement from an international, multidisciplinary workshop sponsored by the Pituitary Society offers evidence-based graded consensus recommendations and key summary points for clinical practice on the diagnosis and management of prolactinomas. Epidemiology and pathogenesis, clinical presentation of disordered pituitary hormone secretion, assessment of hyperprolactinaemia and biochemical evaluation, optimal use of imaging strategies and disease-related complications are addressed. In-depth discussions present the latest evidence on treatment of prolactinoma, including efficacy, adverse effects and options for withdrawal of dopamine agonist therapy, as well as indications for surgery, preoperative medical therapy and radiation therapy. Management of prolactinoma in special situations is discussed, including cystic lesions, mixed growth hormone-secreting and prolactin-secreting adenomas and giant and aggressive prolactinomas. Furthermore, considerations for pregnancy and fertility are outlined, as well as management of prolactinomas in children and adolescents, patients with an underlying psychiatric disorder, postmenopausal women, transgender individuals and patients with chronic kidney disease. The workshop concluded that, although treatment resistance is rare, there is a need for additional therapeutic options to address clinical challenges in treating these patients and a need to facilitate international registries to enable risk stratification and optimization of therapeutic strategies.

Comparative effectiveness of endoscopic and microscopic adenoma removal in acromegaly

Introduction

Somatotropinomas are the main cause of acromegaly. Surgery is the primary and most efficient method of treatment. The study aimed to compare the radicality of small-sized and medium (<30 mm) somatotropinoma removal and the incidence of postoperative complications in patients with acromegaly when using microscopic and endoscopic techniques.

Methods

In this randomized controlled trial, a total of 83 patients with acromegaly underwent transspheroidal endoscopy or microscopic surgery. Somatotropinoma was the cause of acromegaly in all cases. Patients were randomly divided into two comparison groups depending on the applied surgical technique. Group 1 (n = 40) consisted of patients who underwent adenomectomy with transnasal transsphenoidal access by a microscope. Group 2 (n = 43) included patients who underwent the same surgical procedure with an endoscope. The following indicators were assessed: radicality of tumor removal, treatment effectiveness, postoperative complications, and remission rate.

Results

The study has shown that removal of somatotropinoma in patients with acromegaly using endoscopic technique increases the radicality of tumor removal in comparison with microscopic technique. Total removal of somatotropinoma was successful in 88.4% of cases when using the endoscopic technique. Secondly, the segmentation of patients according to their tumor characteristics poses challenges, primarily owing to the rarity of acromegaly as a disease. The difference between groups was not statistically significant (p=1.02). There were no statistically significant differences in basal GH level and IGF-1 level between groups (p=0.546 and p=0.784, respectively).

Discussion

Endonasal transsphenoidal endoscopic adenomectomy is proven efficacy, a less traumatic degree, and higher somatotropinoma removal radicality. Both surgical methods lead to disease remission.

Differentiation of silent corticotroph pituitary neuroendocrine tumors (PitNETs) from non-functioning PitNETs using kinetic analysis of dynamic MRI

PURPOSE

Silent corticotroph pituitary adenomas (SCAs)/pituitary neuroendocrine tumors (PitNETs) are common non-functioning pituitary adenomas (NFAs)/PitNETs with a clinically aggressive course. This study aimed to investigate the ability of time-intensity analysis of dynamic magnetic resonance imaging (MRI) for distinguishing adrenocorticotropic hormone (ACTH)-positive SCAs and ACTH-negative SCAs from other NFAs.

MATERIALS AND METHODS

We retrospectively evaluated the dynamic MRI findings of patients with NFAs. The initial slope of the kinetic curve (slopeini) obtained by dynamic MRI for each tumor was analyzed using a modified empirical mathematical model. The maximum slope of the kinetic curve (slopemax) was obtained by geometric calculation.

RESULTS

A total of 106 patients with NFAs (11 ACTH-positive SCAs, 5 ACTH-negative SCAs, and 90 other NFAs) were evaluated. The kinetic curves of ACTH-positive SCAs had significantly lesser slopeini and slopemax compared with ACTH-negative SCAs (P = 0.040 and P = 0.001, respectively) and other NFAs (P = 0.018 and P = 0.035, respectively). Conversely, the slopeini and slopemax were significantly greater in ACTH-negative SCAs than in NFAs other than ACTH-negative SCAs (P = 0.033 and P = 0.044, respectively). In receiver operating characteristic analysis of ACTH-positive SCAs and other NFAs, the area under the curve (AUC) values for slopeini and slopemax were 0.762 and 0748, respectively. In predicting ACTH-negative SCAs, the AUC values for slopeini and slopemax were 0.784 and 0.846, respectively.

CONCLUSIONS

Dynamic MRI can distinguish ACTH-positive SCAs and ACTH-negative SCAs from other NFAs.

Quantitative proteomics identified a novel invasion biomarker associated with EMT in pituitary adenomas

BACKGROUND

Complete resection of invasive pituitary adenoma is usually difficult, resulting in a high recurrence rate. Therefore, it is needed to find potential diagnostic markers and therapeutic targets for invasive pituitary adenoma.

METHODS

We collected samples from patients with invasive and non-invasive pituitary adenomas from Beijing Tiantan Hospital for protein extraction and quantitative analysis. We identified differential proteins (DEPs) by differential analysis of the two groups. The intersection of differential proteins related to invasion and epithelial-mesenchymal transition (EMT) in the GeneCards database was identified as EMT-DEPs. The protein network of EMT-DEPs was analyzed using the STRING database and Cytoscape software, and the hub EMT-DEPs were obtained by the MCC algorithm of the cytoHubba plugin. Correlation analysis was used to obtain the interpairing proteins among EMT-DEPs, and core EMT-DEPs were identified based on the number of paired proteins. The Venn program was used to identify the intersection of hub EMT-DEPs and core EMT-DEPs as key EMT-DEPs. Finally, a series of analyses plus experiments were used to verify the correlation of the target protein with invasion and EMT in pituitary adenoma.

RESULTS

Quantitative comparison of proteins between invasive and non-invasive pituitary adenomas indicated 833 differential proteins. The overlaps of EMT-related proteins and differential proteins consisted of 46 EMT-DEPs. There were 6 intersections between the hub EMT-DEPs and core EMT-DEPs. Using quantitative protein data and GSE169498 chip, we found that solute carrier family 2 member 1 (SLC2A1) was our target protein. SLC2A1 was significantly correlated with the invasiveness of pituitary adenoma, and the ROC curve was satisfactory. The functions and pathways of SLC2A1 and paired protein enrichment were closely linked to the EMT. Consistently, SLC2A1 expression was significantly and positively correlated with the expression of classical markers of EMT. The final experiment revealed that SLC2A1 was significantly upregulated in invasive pituitary adenoma.

CONCLUSION

SLC2A1 is significantly upregulated in invasive pituitary adenoma with satisfactory predictive value. It may regulate EMT. It may be a potential diagnostic marker for invasive pituitary adenoma.

Cushing's disease in children: unique features and update on genetics

In this brief report, we review the unique characteristics of Cushing disease (CD) in children, as well as the most important new genetic discoveries associated with childhood CD. We often forget it, but CD refers to Cushing syndrome caused by pituitary corticotroph adenomas only. Thus, here we only refer to the new discoveries associated with pituitary tumors. There is indeed a wealth of new information on clinical features, outcomes, and genetic determinants of CD in children!

Pituitary adenomas in the elderly: Retrospective comparative analysis of clinical/tumor features and surgical data by age group

The increase in life expectancy along with technological advances has translated into a higher number of pituitary adenomas (PA) diagnosed from the age of 65. In the elderly, symptoms related to comorbidities might overlap with endocrine dysfunction, in addition to increasing anesthetic and surgical risks. This study aimed to compare baseline clinical and tumor features between patients with PA from different age groups: younger adults (YA), 18 to 64 years, and older adults (OA), ≥65 years. As secondary outcomes, we also intended to assess: clinical characteristics and tumor features in patients undergoing surgical intervention and surgical data and complications in patients undergoing transphenoidal surgery (TSS). This retrospective cohort study included patients diagnosed with PA in adulthood divided into YA and OA groups. The secondary outcomes were evaluated in the subgroups: patients who underwent pituitary surgery and patients specifically submitted to TSS, who had completed postoperative follow-up ≥ 6 months until July/2020. A total of 401 patients were included, 327 (81.5%) in the YA and 74 (18.5%) in the OA group. Hormone-secreting effects were more common in the YA group (P < .001) and mass effects in the OA group (P = .070). The prevalence of hypertension and diabetes was higher in the OA group (P = .002, P = .011). A larger proportion of nonfunctioning (NF) PA and prolactinomas was found in OA (P < .001) and YA (P = .012), respectively. Macroadenomas were more common in the OA group (P < .001). No differences were found in terms of invasiveness. In the secondary outcome analysis, there was a higher prevalence of NF-PA in those who underwent pituitary surgery. The rate of TSS-related complications was similar between the groups for major, minor and endocrine/electrolyte complications. OA-PA clinically differ from the younger: tend to present more frequently with chronic comorbidities and less frequently with hormone-secreting effects, are more often NF and larger in size without a significant increase in invasiveness. The TSS results were reassuring, proving to be equally safe for the elderly.

High Histone Deacetylase 2/3 Expression in Non-Functioning Pituitary Tumors

Epigenetic modification of chromatin is involved in non-malignant pituitary neoplasia by causing abnormal expression of tumor suppressors and oncogenes. These changes are potentially reversible, suggesting the possibility of targeting tumor cells by restoring the expression of epigenetically silenced tumor suppressors. The role of the histone deacetylase (HDAC) family in pituitary tumorigenesis is not known. We report that HDAC2 and 3, Class I HDAC members, are highly expressed in clinically non-functioning pituitary adenomas (NFPAs) compared to normal pituitary (NP) samples as determined by RT-PCR and immunohistochemical staining (IHC). Treatment of a human NFPA derived folliculostellate cell line, PDFS, with the HDAC3 inhibitor RGFP966 for 96 hours resulted in inhibition of cell proliferation by 70%. Furthermore, the combination of RGFP966 with a methyltransferase/DNMT inhibitor, 5’-aza-2’-deoxycytidine, led to the restoration of the expression of several tumor suppressor genes, including STAT1, P16, PTEN, and the large non-coding RNA tumor suppressor MEG3, in PDFS cells. Our data support the hypothesis that both histone modification and DNA methylation are involved in the pathogenesis of human NFPAs and suggest that targeting HDACs and DNA methylation can be incorporated into future therapies.

High-risk pituitary adenomas and strategies for predicting response to treatment

High-risk pituitary adenomas are aggressive. They show clinical and imaging features similar to those of carcinomas, including infiltration of the surrounding brain structures, but lack cerebrospinal or systemic metastases. In addition, they display distinct behavior, including tendency for fast growth and frequent recurrences, which are difficult to control. The term "high-risk" adenoma was first introduced in the 4th edition of the World Health Organization Classification of Endocrine Tumors in 2017. Five defined adenoma types belong to this category, including sparsely granulated somatotroph, lactotroph in men, Crooke cell, silent corticotroph, and plurihormonal PIT-1 positive adenomas. The morphological and immunohistochemical characteristics of high-risk adenomas are herein described in detail. In addition, the clinical features and the treatment options are presented. This review focuses on predictive markers assessed by immunohistochemistry, which help clinicians to design the appropriate treatment strategies for high-risk adenomas. Somatostatin receptor status predicts effectiveness of postsurgical treatment with somatostatin analogs, and MGMT expression predicts response to treatment with temozolomide. This comprehensive review presents the clinical and pathological features of high-risk pituitary adenomas, underlines the contribution of immunohistochemistry, and emphasizes the leading role of pathology in the design of optimal clinical management.

A Preoperative MRI-Based Radiomics-Clinicopathological Classifier to Predict the Recurrence of Pituitary Macroadenoma Within 5 Years

Objective: To investigate the ability of a MRI-based radiomics-clinicopathological model to predict pituitary macroadenoma (PMA) recurrence within 5 years.

Materials and Methods: We recruited 74 recurrent and 94 non-recurrent subjects, following first surgery with 5-year follow-up data. Univariate and multivariate analyses were conducted to identify independent clinicopathological risk factors. Two independent and blinded neuroradiologists used 3D-Slicer software to manually delineate whole tumors using preoperative axial contrast-enhanced T1WI (CE-T1WI) images. 3D-Slicer was then used to extract radiomics features from segmented tumors. Dimensionality reduction was carried out by the least absolute shrinkage and selection operator (LASSO). Two multilayer perceptron (MLP) models were established, including independent clinicopathological risk factors (Model 1) and a combination of screened radiomics features and independent clinicopathological markers (Model 2). The predictive performance of these models was evaluated by receiver operator characteristic (ROC) curve analysis.

Results: In total, 1,130 features were identified, and 4 of these were selected by LASSO. In the test set, the area under the curve (AUC) of Model 2 was superior to Model 1 {0.783, [95% confidence interval (CI): 0.718—.860] vs. 0.739, (95% CI: 0.665–0.818)}. Model 2 also yielded the higher accuracy (0.808 vs. 0.692), sensitivity (0.826 vs. 0.652), and specificity (0.793 vs. 0.724) than Model 1.

Conclusions: The integrated classifier was superior to a clinical classifier and may facilitate the prediction of individualized prognosis and therapy.

Individualized medical treatment options in Cushing disease

Cushing disease (CD) is caused by a pituitary tumor which oversecretes adrenocorticotropic hormone (ACTH). It is a serious endocrine disease associated with increased mortality and impaired quality of life. The management of CD remains challenging. Although transsphenoidal surgery is the treatment of choice in most cases, in approximately half of CD patients, second or third-line treatment options are needed. Currently, new medical therapies are available which target adrenal steroidogenesis, pituitary somatostatin and dopamine receptors, and glucocorticoid receptors. Selection of which medication to use should be individualized and is determined by many factors including severity of the disease, possible side effects, patients preferences and local availability. The aim of this article is to describe currently available medical therapy to help clinicians individualize the treatment options in the context of recently updated Pituitary Society recommendations.

Characteristics and overall survival in pediatric versus adult pituitary adenoma: a National Cancer Database analysis

OBJECTIVE

Pituitary adenomas in the pediatric population are extremely rare, resulting in limited information in the literature on these patients. In this study, data from the National Cancer Database (NCDB) to compare pituitary adenoma clinical presentations, treatment management patterns, and overall survival between pediatric and adult patients.

METHODS

The NCDB was queried for all cases of histologically confirmed pituitary adenoma treated between 2004 and 2015. Patients were primarily stratified as either pediatric (< 18 years) or adult (≥ 18 years). Patient demographics/socioeconomics and resulting outcomes were then compared.

RESULTS

1893 pediatric and 77,993 adult patients with pituitary adenomas were evaluated. Average tumor size for pediatric and adult patients was 13.6 ± 13.2 mm and 20.1 ± 13.1 mm, respectively (p < 0.001). Pediatric patients were more likely to undergo gross total resection, less likely to receive adjuvant radiation, more likely to receive medical therapy, more likely to undergo active surveillance, and exhibited improved 5-year and 10-year overall survival (OS) (all p < 0.001). Temporal analysis demonstrated a significant increase in endoscopic approach over time (from 48 to 65%) in the pediatric population (R² = 0.722, p = 0.03). On univariate analysis in the pediatric population, African American race compared to Caucasians (HR: 5.85, 95% CI 1.79-19.2, p < 0.003), patients with government insurance compared to those with private insurance (HR: 5.07, 95% CI 1.31-19.6, p < 0.02) and uninsured patients compared to those with private insurance (HR: 14.4, 95% CI 2.41-86.5, p < 0.003) were associated with decreased OS. Lastly, patients who underwent GTR had improved OS compared to those who underwent subtotal resection (HR: 0.08, 95% CI 0.008-0.93, p < 0.04) in the pediatric population.

CONCLUSIONS

Compared to adults, children with pituitary adenomas more commonly underwent GTR, less frequently underwent adjuvant radiotherapy, more frequently underwent medical management and active surveillance, and had improved survival. Temporal analysis demonstrated increasing utilization of the endoscopic approach for surgical treatment of pediatric and adult pituitary adenoma patients.

LEVEL OF EVIDENCE

Level III.

Long-Term Use of Temozolomide as Safe and Effective Therapy for an Aggressive Corticotroph Adenoma in a Very Old Patient

Background

Temozolomide (TMZ) is safe and effective in the treatment of aggressive pituitary adenomas (PAs). However, the optimal duration of TMZ therapy is still unknown. Moreover, data about administration of TMZ in elderly (≥65 years) people to treat aggressive PAs are scarce. We report the case of the oldest female patient undergoing the longest TMZ protocol described so far to treat an aggressive, initially silent corticotroph PA.

Case report

The patient initially underwent partial surgical removal of the PA. Subsequent treatment with cabergoline was applied, but it was unsuccessful in controlling the growth of the residual tumor. Pasireotide and external radiation also showed to be ineffective; therefore, treatment with TMZ was started at the standard dose of 200 mg/m²/day for 5 days every 4 weeks for a total of 47 cycles. At the time of treatment’s beginning, the patient was 83 years old. Radiological follow-up documented a progressive, remarkable reduction of the adenoma and the last imaging, after 39 cycles of TMZ, showed an intrasellar lesion with large areas of cystic degeneration. The patient also developed adrenal deficiency managed with glucocorticoid replacement. No major side effects were observed throughout the treatment, with exception of nausea, well controlled with anti-emetic medication. TMZ therapy was discontinued after 47 cycles; hormonal and imaging follow-up investigations documented sustained functional and dimensional response.

Conclusions

Our case supports the long-term use of TMZ, confirming its safety and efficacy also for elderly patients.

Classic cardiovascular risk factors improve in very elderly hypopituitary patients treated on standard hormone replacement in long term follow- up

Background

Hypopituitarism in the elderly population is an underdiagnosed condition and may increase comorbidities related to glucose metabolism, dyslipidemia, and cardiovascular risk factors. Optimization of hormone replacement that considers alterations in clearance rates of hormones, interaction with other medications, and evaluation of the risk-benefit ratio of treatment is a big challenge for clinical practice.

Objectives

This study aimed to evaluate classic cardiovascular risk factors in hypopituitary septuagenarians and octagenarians by diagnosis and after long-term hormone replacement.

Methods

This is a retrospective observational study, with patients recruited and selected from a registry in a tertiary medical center. We included patients aged 70–99 years with hypopituitarism, evaluated hormonal and biochemical parameters, and cardiovascular risk scores were calculated by diagnosis and compared after long-term follow-up. All patients gave informed consent. Patient data were compared to a sex and age-matched control group, with long-term geriatric follow-up, without endocrine diseases.

Results

Thirty-five patients were included, 16 patients aged 70–75 years (72.61), 12 patients 76–80 years (72.28), 7 patients 81–99 years (89.28). Pituitary macroadenomas were the main cause of hypopituitarism, mean maximal diameter 3.4 cm (2.9–4.3), and invasive craniopharyngiomas. At the moment of diagnosis, most patients were overweight, and abdominal adiposity was observed in 76.9% of women and 36.4% of men, primarily in octagenarians and nonagenarians. Comorbidities were frequent; 85.7% presented hypertension, 37.1% diabetes, 53.1% low HDL, 51.5% hypertriglyceridemia. Most patients presented more than two combined pituitary deficiencies; hypogonadism in 88.6%, central hypothyroidism in 82.9%, GH deficiency in 65.7%, and adrenal insufficiency in 25.7%. Analysis of cardiovascular risk prediction in the total cohort showed that 57.1% of patients presented a reduction in the General Cardiovascular Disease (CVD) Risk Prediction Score and 45.7% in atherosclerotic CVD risk estimated by ACC/AHA 2013 Pooled Cohort Equation, despite being submitted to conventional hormone replacement, during the mean follow-up of 14.5 years. This reduction was not observed in the control group.

Discussion and conclusion

In this study, aged hypopituitary patients presented a reduction in estimated general CVD risk during long-term follow-up, despite replacement with corticosteroids, levothyroxine, or gonadal steroids. Early diagnosis and treatment of hypopituitarism in the elderly remain challenging. Larger studies should be performed to assess the risk-benefit ratio of hormone replacement on the metabolic profile in septuagenarian and octogenarian patients.

Multiple Endocrine Neoplasia Type 1: Latest Insights

Multiple endocrine neoplasia type 1 (MEN1), a rare tumor syndrome that is inherited in an autosomal dominant pattern, is continuing to raise great interest for endocrinology, gastroenterology, surgery, radiology, genetics, and molecular biology specialists. There have been 2 major clinical practice guidance papers published in the past 2 decades, with the most recent published 8 years ago. Since then, several new insights on the basic biology and clinical features of MEN1 have appeared in the literature, and those data are discussed in this review. The genetic and molecular interactions of the MEN1-encoded protein menin with transcription factors and chromatin-modifying proteins in cell signaling pathways mediated by transforming growth factor β/bone morphogenetic protein, a few nuclear receptors, Wnt/β-catenin, and Hedgehog, and preclinical studies in mouse models have facilitated the understanding of the pathogenesis of MEN1-associated tumors and potential pharmacological interventions. The advancements in genetic diagnosis have offered a chance to recognize MEN1-related conditions in germline MEN1 mutation-negative patients. There is rapidly accumulating knowledge about clinical presentation in children, adolescents, and pregnancy that is translatable into the management of these very fragile patients. The discoveries about the genetic and molecular signatures of sporadic neuroendocrine tumors support the development of clinical trials with novel targeted therapies, along with advancements in diagnostic tools and surgical approaches. Finally, quality of life studies in patients affected by MEN1 and related conditions represent an effort necessary to develop a pharmacoeconomic interpretation of the problem. Because advances are being made both broadly and in focused areas, this timely review presents and discusses those studies collectively.

A Preoperative MRI-Based Radiomics-Clinicopathological Classifier to Predict the Recurrence of Pituitary Macroadenoma Within 5 Years

Objective: To investigate the ability of a MRI-based radiomics-clinicopathological model to predict pituitary macroadenoma (PMA) recurrence within 5 years. Materials and Methods: We recruited 74 recurrent and 94 non-recurrent subjects, following first surgery with 5-year follow-up data. Univariate and multivariate analyses were conducted to identify independent clinicopathological risk factors. Two independent and blinded neuroradiologists used 3D-Slicer software to manually delineate whole tumors using preoperative axial contrast-enhanced T1WI (CE-T1WI) images. 3D-Slicer was then used to extract radiomics features from segmented tumors. Dimensionality reduction was carried out by the least absolute shrinkage and selection operator (LASSO). Two multilayer perceptron (MLP) models were established, including independent clinicopathological risk factors (Model 1) and a combination of screened radiomics features and independent clinicopathological markers (Model 2). The predictive performance of these models was evaluated by receiver operator characteristic (ROC) curve analysis. Results: In total, 1,130 features were identified, and 4 of these were selected by LASSO. In the test set, the area under the curve (AUC) of Model 2 was superior to Model 1 {0.783, [95% confidence interval (CI): 0.718-.860] vs. 0.739, (95% CI: 0.665-0.818)}. Model 2 also yielded the higher accuracy (0.808 vs. 0.692), sensitivity (0.826 vs. 0.652), and specificity (0.793 vs. 0.724) than Model 1. Conclusions: The integrated classifier was superior to a clinical classifier and may facilitate the prediction of individualized prognosis and therapy.

PBK/TOPK Inhibitor Suppresses the Progression of Prolactinomas

BACKGROUND

Prolactinoma is the most common type of pituitary tumors, and its resultant tumor occupying and hormone disturbance greatly damage the health of patients. In this study, we investigated a protein kinase-PDZ Binding Kinase (PBK)/T-LAK Cell-Originated Protein Kinase (TOPK) as a candidate protein regulating prolactin (PRL) secretion and tumor growth of prolactinomas.

METHODS

Downloaded prolactinoma transcriptome dataset from Gene Expression Omnibus (GEO) database, and screened differentially expressed genes (DEGs) between normal pituitary tissues and prolactinoma tissues. Then, Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses of DEGs were performed, a protein-protein interaction (PPI) network was constructed and the hub genes were identified. After a literature search, TOPK was presumed as an candidate target regulating the prolactinoma. We found a specific inhibitor of TOPK to investigate its effects on the proliferation, migration, apoptosis and PRL secretion of pituitary tumor cells. Finally, the regulation of TOPK inhibitor on its downstream target-p38 Mitogen Activated Protein Kinase (p38 MAPK) was detected to explore the potential mechanism.

RESULTS

A total of 361 DEGs were identified, and 20 hub genes were screened out. TOPK inhibitor HI-TOPK-032 could suppress the proliferation & migration and induce apoptosis of pituitary tumor cells in vitro, and reduce PRL secretion and tumor growth in vivo. HI-TOPK-032 also inhibited the phosphorylation level of the downstream target p38 MAPK, suggesting that TOPK inhibitors regulate the development of prolactinoma by mediating p38 MAPK.

CONCLUSION

Our study of identification and functional validation of TOPK suggests that this candidate can be a promising molecular target for prolactinoma treatment.

Aggressive Cushing's Disease: Molecular Pathology and Its Therapeutic Approach

Cushing's disease is a syndromic pathological condition caused by adrenocorticotropic hormone (ACTH)-secreting pituitary adenomas (ACTHomas) mediated by hypercortisolemia. It may have a severe clinical course, including infection, psychiatric disorders, hypercoagulability, and metabolic abnormalities, despite the generally small, nonaggressive nature of the tumors. Up to 20% of ACTHomas show aggressive behavior, which is related to poor surgical outcomes, postsurgical recurrence, serious clinical course, and high mortality. Although several gene variants have been identified in both germline and somatic changes in Cushing's disease, the pathophysiology of aggressive ACTHomas is poorly understood. In this review, we focused on the aggressiveness of ACTHomas, its pathology, the current status of medical therapy, and future prospects. Crooke's cell adenoma (CCA), Nelson syndrome, and corticotroph pituitary carcinoma are representative refractory pituitary tumors that secrete superphysiological ACTH. Although clinically asymptomatic, silent corticotroph adenoma is an aggressive ACTH-producing pituitary adenoma. In this review, we summarize the current understanding of the pathophysiology of aggressive ACTHomas, including these tumors, from a molecular point of view based on genetic, pathological, and experimental evidence. The treatment of aggressive ACTHomas is clinically challenging and usually resistant to standard treatment, including surgery, radiotherapy, and established medical therapy (e.g., pasireotide and cabergoline). Temozolomide is the most prescribed pharmaceutical treatment for these tumors. Reports have shown that several treatments for patients with refractory ACTHomas include chemotherapy, such as cyclohexyl-chloroethyl-nitrosourea combined with 5-fluorouracil, or targeted therapies against several molecules including vascular endothelial growth factor receptor, cytotoxic T lymphocyte antigen 4, programmed cell death protein 1 (PD-1), and ligand for PD-1. Genetic and experimental evidence indicates that some possible therapeutic candidates are expected, such as epidermal growth factor receptor tyrosine kinase inhibitor, cyclin-dependent kinase inhibitor, and BRAF inhibitor. The development of novel treatment options for aggressive ACTHomas is an emerging task.

UPDATES IN AGGRESSIVE PITUITARY TUMORS

Aggressive pituitary tumors lie between pituitary adenomas and carcinomas, displaying a particular behavior, with invasion, resistance to conventional therapy and early recurrence. The radiological grading, along with prognostic markers such as Ki-67 proliferation index, p53, MGMT and transcription factors are important factors in establishing the benign, aggressive, or malignant nature of pituitary tumors, with a more accurate treatment strategy. In this article, we report the novelties in defining, classifying, and managing aggressive pituitary tumors and their malignant potential, focusing on clinicopathological, histological, molecular and radiological data.