Disulfiram mediated anti-tumour effect in pituitary neuroendocrine tumours by inducing cuproptosis

CONTEXT

Medical treatment plays a critical role in pituitary neuroendocrine tumour (PitNET) treatment. Dopamine agonists and somatostatin receptor agonists are the only known drugs for effectively treating PitNET. Thus, the identification of potential therapeutic targets and drugs is urgently needed.

OBJECTIVE

To discover potential drugs that can suppress PitNET growth and to further investigate the underlying mechanism involved.

METHODS

High-throughput drug screening of primary cultures of 17 patient-derived PitNETs was performed to identify potential therapeutic compounds. Cell viability assays, Western blot analysis and flow cytometry were used to investigate pituitary neuroendocrine tumour cell lines and patient-derived PitNET cultures in vitro. In vivo drug efficacy was examined in a mouse xenograft model.

RESULTS

Seventeen primary PitNET samples were collected for high-throughput drug screening, and a class of copper ionophores that can effectively inhibit cell growth, such as zinc pyrithione, elesclomol, and disulfiram (DSF), was identified. Subsequent experiments initially validated the dose-dependent cell growth-suppressing effect of these copper ionophores on AtT20, GH3, and MMQ cells and several primary PitNET cell lines. Moreover, we confirmed that the cytotoxic effect of DSF depends on the presence of copper. Additionally, we determined that cell death occurs via cuproptosis, with events such as Fe-S cluster protein loss, dihydrolipoyl transacetylase oligomerization and heat shock protein 70 upregulation. Finally, we verified the cytotoxic effects of DSF in vivo.

CONCLUSION

The present study revealed copper ionophores as a potential class of drugs for PitNET treatment. DSF induced PitNET cell death via cuproptosis and might be a promising option for PitNET therapy.

Single-cell transcriptomics reveal distinct immune-infiltrating phenotypes and macrophage-tumor interaction axes among different lineages of pituitary neuroendocrine tumors

BACKGROUND

Pituitary neuroendocrine tumors (PitNETs) are common gland neoplasms demonstrating distinctive transcription factors. Although the role of immune cells in PitNETs has been widely recognized, the precise immunological environment and its control over tumor cells are poorly understood.

METHODS

The heterogeneity, spatial distribution, and clinical significance of macrophages in PitNETs were analyzed using single-cell RNA sequencing (scRNA-seq), bulk RNA-seq, spatial transcriptomics, immunohistochemistry, and multiplexed quantitative immunofluorescence (QIF). Cell viability, cell apoptosis assays, and in vivo subcutaneous xenograft experiments have confirmed that INHBA-ACVR1B influences the process of tumor cell apoptosis.

RESULTS

The present study evaluated scRNA-seq data from 23 PitNET samples categorized into 3 primary lineages. The objective was to explore the diversity of tumors and the composition of immune cells across these lineages. Analyzed data from scRNA-seq and 365 bulk RNA sequencing samples conducted in-house revealed the presence of three unique subtypes of tumor immune microenvironment (TIME) in PitNETs. These subtypes were characterized by varying levels of immune infiltration, ranging from low to intermediate to high. In addition, the NR5A1 lineage is primarily associated with the subtype characterized by limited infiltration of immune cells. Tumor-associated macrophages (TAMs) expressing CX3CR1+, C1Q+, and GPNMB+ showed enhanced contact with tumor cells expressing NR5A1 + , TBX19+, and POU1F1+, respectively. This emphasizes the distinct interaction axes between TAMs and tumor cells based on their lineage. Moreover, the connection between CX3CR1+ macrophages and tumor cells via INHBA-ACVR1B regulates tumor cell apoptosis.

CONCLUSIONS

In summary, the different subtypes of TIME and the interaction between TAM and tumor cells offer valuable insights into the control of TIME that affects the development of PitNET. These findings can be utilized as prospective targets for therapeutic interventions.

Therapeutic potential of targeting Nrf2 by panobinostat in pituitary neuroendocrine tumors

We aimed to identify the druggable cell-intrinsic vulnerabilities and target-based drug therapies for PitNETs using the high-throughput drug screening (HTS) and genomic sequencing methods. We examined 9 patient-derived PitNET primary cells in HTS. Based on the screening results, the potential target genes were analyzed with genomic sequencing from a total of 180 PitNETs. We identified and verified one of the most potentially effective drugs, which targeted the Histone deacetylases (HDACs) both in in vitro and in vivo PitNET models. Further RNA sequencing revealed underlying molecular mechanisms following treatment with the representative HDACs inhibitor, Panobinostat. The HTS generated a total of 20,736 single-agent dose responses which were enriched among multiple inhibitors for various oncogenic targets, including HDACs, PI3K, mTOR, and proteasome. Among these drugs, HDAC inhibitors (HDACIs) were, on average, the most potent drug class. Further studies using in vitro, in vivo, and isolated PitNET primary cell models validated HDACIs, especially Panobinostat, as a promising therapeutic agent. Transcriptional surveys revealed substantial alterations to the Nrf2 signaling following Panobinostat treatment. Moreover, Nrf2 is highly expressed in PitNETs. The combination of Panobinostat and Nrf2 inhibitor ML385 had a synergistic effect on PitNET suppression. The current study revealed a class of effective anti-PitNET drugs, HDACIs, based on the HTS and genomic sequencing. One of the representative compounds, Panobinostat, may be a potential drug for PitNET treatment via Nrf2-mediated redox modulation. Combination of Panobinostat and ML385 further enhance the effectiveness for PitNET treatment.

[Analysis of clinical characteristics of persistent HBeAg positivity in patients with chronic hepatitis B treated with nucleos(t)ide analogues]

Objective: To explore the clinical characteristics of persistent HBeAg positivity in patients with chronic hepatitis B treated with nucleos(t)ide analogues. Methods: A retrospective analysis was performed according to different data types. An independent sample t-test, Mann-Whitney U test, chi-square test, or Fisher's exact probability method were used. Chronic hepatitis B patients followed up for four years were collected from the follow-up case database of the Department of Infectious Diseases of Zhongshan Third Hospital from January 2009 to December 2018 and were divided into two groups, A and B, with 87 and 145 cases respectively, according to the duration of HBeAg-negativity≤ 3 and persistent positivity >3 years. Statistical analysis was conducted on the age, gender, family history, baseline, follow-up visit duration, liver function, and other data among the two patient groups. Results: There were no statistically significant differences in gender, age, family history of liver cirrhosis, family history of liver cancer, liver cirrhosis condition before treatment, fatty liver disease combined condition before treatment, baseline HBsAg, anti-HBc, alanine aminotransferase, albumin, or total bilirubin between the two groups of patients (P > 0.05). HBV DNA and HBeAg were significantly higher in group B than those in group A at baseline, with P≤0.001. Aspartate aminotransferase and γ-glutamyl transferase were significantly higher in group A than those in group B at baseline. The proportion of family history of hepatitis B was significantly higher in group B (69.0%) than that in group A (50.6%) among the two groups of patients, and the difference was statistically significant (P = 0.005). The proportion of mothers with hepatitis B was significantly higher in group B (25.5%) than in group A (11.5%), P = 0.010. During the treatment process, the HBV DNA quantification was significantly higher in group B than that in group A at 0.5 and 1 years (P≤0.002). The proportion of HBV DNA <100IU/ml was also significantly different at six months and one year (χ(2)=30.327, P < 0.001 and χ(2)=11.779, P = 0.001). The HBsAg level was higher in group B than that of group A in the second and fourth years, P < 0.05. During the entire treatment process, the HBeAg level was significantly higher in group B than that in group A (P < 0.001). A total of seven cases developed liver cirrhosis or cancer during follow-up, including three cases in group A and four cases in group B (P > 0.05). Conclusion: HBeAg-positive patients with chronic hepatitis B have persistent HBeAg positivity when treated with long-term nucleos(t)ide analogues. Accordingly, a greater proportion of this kind of patient family and mothers have a remarkable history of hepatitis B and a reduced HBV DNA relapse rate in the early stages (within a year or less).

Alternations of Blood Pressure Following Surgical or Drug Therapy for Prolactinomas

Several subtypes of pituitary neuroendocrine tumors (PitNETs), such as acromegaly and Cushing's disease, can result in hypertension. However, whether prolactinoma is associated with this complication remains unknown. Moreover, the effect of treatment with surgery or drugs on blood pressure (BP) is unknown. Herein, a retrospective study reviewed 162 patients with prolactinoma who underwent transsphenoidal surgery between January 2005 and December 2022. BP measurements were performed 1 day before and 5 days after surgery. Accordingly, patients' medical characteristics were recorded. In addition, in situ rat and xenograft nude-mice prolactinoma models have been used to mimic prolactinoma. In vivo BP and serum prolactin (PRL) levels were measured after cabergoline (CAB) administration in both rats and mice. Our data suggest that surgery can effectively decrease BP in prolactinoma patients with or without hypertension. The BP-lowering effect was significantly associated with several variables, including age, sex, disease duration, tumor size, invasion, dopamine agonists (DAs)-resistance, recurrence, and preoperative PRL levels. Moreover, in situ and xenograft prolactinomas induced BP elevation, which was alleviated by CAB treatment without and with a statistical difference in rats and mice, respectively. Thus, surgery or CAB can decrease BP in prolactinoma, indicating that pre- and postoperative BP management becomes essential.

Alleviating CB2-Dependent ER Stress and Mitochondrial Dysfunction Improves Chronic Cerebral Hypoperfusion-Induced Cognitive Impairment

Augmentation of endoplasmic reticulum (ER) stress may trigger excessive oxidative stress, which induces mitochondrial dysfunction. The fatty acid amide hydrolase inhibitor, URB597, shows anti-oxidation characteristics in multiple neurological disorders. The present study aimed to determine whether inhibition of ER stress was involved in the protective effects of URB597 against chronic cerebral hypoperfusion (CCH)-induced cognitive impairment. Hippocampal HT-22 cells were exposed to oxygen-glucose deprivation. The cell viability, apoptosis, ER stress, mitochondrial ATP, and oxidative stress levels were assessed following treatment with URB597, benzenebutyric acid (4-PBA), and thapsigargin (TG). Furthermore, the effects of URB597 on ER stress and related pathways were investigated in the CCH animal model, including Morris water maze testing of cognition, western blotting analysis of ER stress signaling, and transmission electron microscopy of mitochondrial and ER ultrastructure changes. The results suggested that cerebral ischemia caused ER stress with upregulation of ER stress signaling-related proteins, mitochondrial dysfunction, neuronal apoptosis, ultrastructural injuries of mitochondria-associated ER membranes, and cognitive decline. Co-immunoprecipitation experiments confirmed the interaction between CB2 and β-Arrestin1. Inhibiting ER stress by URB597 improved these changes by activating CB2/β-Arrestin1 signaling, which was reversed by the CB2 antagonist, AM630. Together, the results identified a novel mechanism of URB597, involving CCH-induced cognitive impairment alleviation of CB2-dependent ER stress and mitochondrial dysfunction. Furthermore, this study identified CB2 as a potential target for therapy of ischemic cerebrovascular diseases.

Fully endoscopic far-lateral supracerebellar infratentorial approach for trigeminal neuralgia: illustrative case reports

BACKGROUND

Trigeminal neuralgia (TN) is a common cause of craniofacial pain. The retrosigmoid approach is usually used to treat TN, but no cases of endoscopic far-lateral supracerebellar infratentorial approach (EF-SCITA) were used to undergo operation for TN.

CASE PRESENTATION

Two patients were presented with severe facial pain and preliminary diagnosis was TN. Preoperative magnetic resonance imaging revealed that a superior cerebellar artery (SCA) compressed the trigeminal nerve in case 1, and a tumor located in the petrous apex extending into the Meckel's cave compressed the trigeminal nerve in case 2. Operations were achieved through the EF-SCITA. The pain was totally relieved with no postsurgical complications in both cases.

CONCLUSIONS

We present the first two case reports of EF-SCITA to relieve classical and secondary TN successfully. The EF-SCITA can be a promising approach for treating TN.

Identification of the enhancer RNAs related to tumorgenesis of pituitary neuroendocrine tumors

Background

Pituitary neuroendocrine tumors (PitNETs), which originate from the pituitary gland, account for 10%-15% of all intracranial neoplasms. Recent studies have indicated that enhancer RNAs (eRNAs) exert regulatory effects on tumor growth. However, the mechanisms underlying the eRNA-mediated tumorigenesis of PitNETs have not been elucidated.

Methods

Normal pituitary and PitNETs tissues were used to identify the differentially expressed eRNAs (DEEs). Immune gene sets and hallmarks of cancer gene sets were quantified based on single sample gene set enrichment analysis (ssGSEA) algorithm using GSVA. The perspective of immune cells among all samples was calculated by the CIBERSORT algorithm. Moreover, the regulatory network composed of key DEEs, target genes of eRNAs, hallmarks of cancer gene sets, differentially expressed TF, immune cells and immune gene sets were constructed by Pearson correlation analysis. Small molecular anti-PitNETs drugs were explored by CMap analysis and the accuracy of the study was verified by in vitro and in vivo experiments, ATAC-seq and ChIP-seq.

Results

In this study, data of 134 PitNETs and 107 non-tumorous pituitary samples were retrieved from a public database to identify differentially expressed genes. In total, 1128 differentially expressed eRNAs (DEEs) (494 upregulated eRNAs and 634 downregulated eRNAs) were identified. Next, the correlation of DEEs with cancer-related and immune-related gene signatures was examined to establish a co-expression regulatory network comprising 18 DEEs, 50 potential target genes of DEEs, 5 cancer hallmark gene sets, 2 differentially expressed transcription factors, 4 immune cell types, and 4 immune gene sets. Based on this network, the following four therapeutics for PitNETs were identified using Connectivity Map analysis: ciclopirox, bepridil, clomipramine, and alexidine. The growth-inhibitory effects of these therapeutics were validated using in vitro experiments. Ciclopirox exerted potential growth-inhibitory effects on PitNETs. Among the DEEs, GNLY, HOXB7, MRPL33, PRDM16, TCF7, and ZNF26 were determined to be potential diagnostic and therapeutic biomarkers for PitNETs.

Conclusion

This study illustrated the significant influence of eRNAs on the occurrence and development of PitNETs. By constructing the co-expression regulation network, GNLY, HOXB6, MRPL33, PRDM16, TCF7, and ZNF26 were identified as relatively significant DEEs which were considered as the novel biomarkers of diagnosis and treatment of PitNETs. This study demonstrated the roles of eRNAs in the occurrence and development of PitNETs and revealed that ciclopirox was a potential therapeutic for pituitary adenomas.

[Risk factors analysis and prediction model establishment of malignant tumor in patients with polymyositis/dermatomyositis]

Objective: To analyze the risk factors of polymyositis/dermatomyositis (PM/DM) complicated with malignant tumor and to construct clinical prediction model. Methods: A total of 427 PM/DM patients, who were admitted to Rheumatism Immunity Branch, the Second Affiliated Hospital, Air Force Medical University from January 1, 2015 to January 1, 2021, were enrolled in the study, including 129 males and 298 females. The mean age was (51.4±12.2) years. The patients were divided into control group (without malignant tumor, n=379) and case group (with malignant tumor, n=48) according to whether they were complicated with malignant tumors. In the two groups, 70% of the patients' clinical data were randomly selected as the training set data, and the remaining 30% were used as the validation set data. The clinical parameters were retrospectively collected, and risk factors of PM/DM complicated with malignant tumor were analyzed by binary logistic regression. R software was used to construct a clinical prediction model for malignant tumors in PM/DM patients using training set data. Validation set data were used to assess the feasibility of the model. The area under the receiver operating characteristic (ROC) curve (AUC), calibration curve and decision curve analysis (DCA) were used to evaluate the predictive ability, accuracy and clinical applicability of the nomogram model. Results: The age of the control group was (50.4±11.8) years, and males accounted for 26.9%(102/379); the age of the case group was (59.1±12.7) years, and the proportion of males was 56.3% (27/48). The proportion of male, age, the positive rate of anti-transcription mediator 1-γ (TIF1-γ) antibody, glucocorticoid therapy resistance, and levels of creatine kinase (CK), carbohydrate antigen 125(CA125) and carbohydrate antigen 199 (CA199) were all higher in the case group than those in control group, while incidence of interstitial lung disease (ILD), arthralgia, Raynaud's phenomenon, serum albumin (ALB) level and lymphocyte (LYM) count were all lower than those in control group (all P<0.05). Binary logistic regression analysis showed that male (OR=2.931, 95%CI: 1.356-6.335), glucocorticoid therapy resistance (OR=5.261, 95%CI: 2.212-12.513), older age (OR=1.056, 95%CI: 1.022-1.091), elevated CA125 (OR=8.327, 95%CI: 2.448-28.319) and positive anti-TIF1-γ antibody (OR=7.529, 95%CI: 2.436-23.270) were risk factors of malignancy in PM/DM patients (all P<0.05); and complicated with ILD (OR=0.261, 95%CI: 0.099-0.689), complicated with arthralgia (OR=0.238,95%CI:0.073-0.779), elevated LYM count (OR=0.267, 95%CI: 0.103-0.691) were protective factors of malignancy in PM/DM patients (all P<0.05). The AUC of ROC curve predicting malignancy in PM/DM patients with the training concentrated prediction model was 0.887 (95%CI: 0.852-0.922), with a sensitivity of 77.9% and a specificity of 86.3%; it was 0.925 (95%CI: 0.890-0.960), 86.5% and 88.0% in the validated centralized prediction model, respectively. The correction curves of the training set and the validation set indicated that the predictive model had good calibration ability. Both the DCA curves of the training set and the validation set showed that the proposed predictive model had good clinical applicability. Conclusions: Older age, male, glucocorticoid therapy resistance, not complicated with ILD and arthralgia, elevated CA125, positive anti-TIF1-γ antibody, decreased LYM count are risk factors for malignancy in PM/DM patients, and the established nomogram model shows good predictive ability.

A systematic survey of LU domain-containing proteins reveals a novel human gene, LY6A, which encodes the candidate ortholog of mouse Ly-6A/Sca-1 and is aberrantly expressed in pituitary tumors

The Ly-6 and uPAR (LU) domain-containing proteins represent a large family of cell-surface markers. In particular, mouse Ly-6A/Sca-1 is a widely used marker for various stem cells; however, its human ortholog is missing. In this study, based on a systematic survey and comparative genomic study of mouse and human LU domain-containing proteins, we identified a previously unannotated human gene encoding the candidate ortholog of mouse Ly-6A/Sca-1. This gene, hereby named LY6A, reversely overlaps with a lncRNA gene in the majority of exonic sequences. We found that LY6A is aberrantly expressed in pituitary tumors, but not in normal pituitary tissues, and may contribute to tumorigenesis. Similar to mouse Ly-6A/Sca-1, human LY6A is also upregulated by interferon, suggesting a conserved transcriptional regulatory mechanism between humans and mice. We cloned the full-length LY6A cDNA, whose encoded protein sequence, domain architecture, and exon-intron structures are all well conserved with mouse Ly-6A/Sca-1. Ectopic expression of the LY6A protein in cells demonstrates that it acts the same as mouse Ly-6A/Sca-1 in their processing and glycosylphosphatidylinositol anchoring to the cell membrane. Collectively, these studies unveil a novel human gene encoding a candidate biomarker and provide an interesting model gene for studying gene regulatory and evolutionary mechanisms.

Mitochondrial Inhibitor Rotenone Triggers and Enhances Neuronal Ferroptosis Following Intracerebral Hemorrhage

Ferroptosis, a form of regulatory non-apoptotic cell death driven by iron-dependent lipid peroxidation, accounts for more than 80% of the total types of neuronal death in the acute phase of intracerebral hemorrhage (ICH). Mitochondria have essential roles in energy production, macromolecule synthesis, cellular metabolism, and cell death regulation. However, its role in ferroptosis remains unclear and somewhat controversial, especially in ICH. This study aimed to investigate whether damaged mitochondria could trigger and enhance neuronal ferroptosis in ICH. The isobaric tag for relative and absolute quantitation proteomics on human ICH samples suggested that ICH caused significant damage to the mitochondria, which presented ferroptosis-like morphology under electron microscopy. Subsequently, use of the mitochondrial special inhibitor Rotenone (Rot) to induce mitochondrial damage showed that it has significant dose-dependent toxicity on primary neurons. Single Rot administration markedly inhibited neuronal viability, promoted iron accumulation, increased malondialdehyde (MDA) contents, decreased total superoxide dismutase (SOD) activity, and downregulated ferroptosis-related proteins RPL8, COX-2, xCT, ASCL4, and GPX4 in primary neurons. Moreover, Rot enhanced these changes via hemin and autologous blood administration in primary neurons and mice, mimicking the in vitro and in vivo ICH models, respectively. Furthermore, Rot exacerbated the ICH-induced hemorrhagic volumes, brain edema, and neurological deficits in mice. Together, our data revealed that ICH induced significant mitochondrial dysfunction and that mitochondrial inhibitor Rot can trigger and enhance neuronal ferroptosis.

DRD2 expression based on 18F-fallypride PET/MR predicts the dopamine agonist resistance of prolactinomas: a pilot study

PURPOSE

The dopamine agonists (DA) have been used widely to treat prolactinomas. However, it is difficult to predict whether the patient will be responsive to DA treatment.

METHODS

We aimed to investigate whether the in vivo expression of DRD2 based on ¹⁸F-fallypride PET/MR could predict the therapeutic effect of DA on prolactinomas. Seven patients with prolactinomas completed ¹⁸F-fallypride PET/MR. Among them, three patients underwent surgery and further tumor immunohistochemistry. Imaging findings and immunohistochemical staining were compared with treatment outcomes.

RESULTS

¹⁸F-fallypride PET/MR was visually positive in 7 of 7 patients, and DRD2 target specificity could be confirmed by immunohistochemical staining. A significantly lower tracer standard uptake value (SUV) could be detected in the resistant patients (n = 3) than in the sensitive patients (n = 4; SUV_mean, 4.67 ± 1.32 vs. 13.57 ± 2.42, p < 0.05). DRD2 expression determined by ¹⁸F-fallypride PET/MR corresponded with the DA treatment response.

CONCLUSION

¹⁸F-fallypride PET/MR may be a promising technique for predicting DA response in patients with prolactinoma.

[New pathological classification and clinical implications of pituitary neuroendocrine tumors of the 2022 WHO version]

In 2022, the World Health Organization proposed a new classification for pituitary adenomas. The major nomenclature change from the previous edition was the transition from"adenoma"to"pituitary neuroendocrine tumor"(PitNETs). The new classification provided the detailed histological subtypes of PitNETs for routine use of antibodies such as pituitary transcription factors (PIT1, TPIT, SF1, GATA3, and ERα) and hormones. The major PIT1, TPIT, and SF1 lineage-defined PitNETs types and subtypes featured distinct morphologic, molecular, and clinical differences. Unlike the 2017 WHO classification, the 2022 WHO version updated some concepts as follows: (1) Mammosomatotroph, acidophil stem cell tumors and mixed somatotroph/lactotroph tumor represented distinct PIT1-lineage PitNETs; (2) The diagnostic category of PIT1-positive plurihormonal tumor was replaced by the immature PIT1-lineage tumor and the mature plurihormonal PIT1-lineage tumor; (3) The term"metastatic PitNET"was advocated to replace the previous terminology"pituitary carcinoma". The new classification emphasizes the importance of pathological classification of PitNETs. Obviously, accurate pathological interpretation is the key to judge the clinical treatment pathway and prognosis of patients.

LBODP077 The Therapeutic Potential Of Targeting Histone Deacetylase For Pituitary Neuroendocrine Tumors By High-throughout Drug Screening

Background

A growing awareness regarding all molecular mechanisms involved in both tumor shrinkage and hormonal control might allow for medical treatment of pituitary neuroendocrine tumors (PitNETs), especially macroadenomas, rather than surgery. However, there are still no effectively therapeutic targets and corresponding drugs for all subtypes of PitNETs.

Methods

To identify druggable cell-intrinsic vulnerabilities and correspondingly promising therapeutic agents, we examined 3 PitNETs cell lines and 21 PitNETs patient-derived primary cell cultures in sequential quantitative high-throughput screens (HTS) of 2149 FDA-approved and bio-active targeted drugs. Furthermore, we verified the most effective drug which targeted the class of mechanistic vulnerabilities, histone deacetylase (HDAC) in vitro and in vivo PitNETs models. Further RNA sequencing was employed to reveal underlying molecular mechanisms following treatment with the most effective HDAC inhibitor, panobinostat.

Results

The HTS effort generated a total of 55296 single-agent dose responses which were enriched among multiple inhibitors for relevant PitNETs oncogenic targets, including HDAC, Akt/mTOR, proteasome, mitogenactivated protein kinase (MEK), and phosphoinositide-3-kinase (PI3K). Inhibitors from these mechanistic classes demonstrated a relatively wide potency-range, with HDAC inhibitors being, on average, the most potent drug class. Further in vitro and In vivo testing in PitNETs models validated HDACi, especially panobinostat as a promising therapeutic approach. Transcriptional surveys revealed substantial alterations to the oxidative redox mediated by the Akt/mTOR1/4EBP1/Nuclear factor-E2-related factor 2 (Nrf2) antioxidant signaling pathway following treatment with panobinostat.

Conclusion

The current study revealed a class of newfound anti-tumor drugs, HDACi based on the HTS technology, which may be potential drugs for the treatment of PitNETs.

Presentation: No date and time listed

TRIM65 determines the fate of a novel subtype of pituitary neuroendocrine tumors via ubiquitination and degradation of TPIT

BACKGROUND

Pituitary neuroendocrine tumors (PitNETs) are common intracranial tumors that are classified into seven histological subtypes, including lactotroph, somatotroph, corticotroph, thyrotroph, gonadotroph, null cell, and plurihormonal PitNETs. However, the molecular characteristics of these types of PitNETs are not completely clear.

METHODS

A total of 180 consecutive cases of PitNETs were collected to perform RNA sequencing. All subtypes of PitNETs were distinguished by unsupervised clustering analysis. We investigated the regulation of TPIT by TRIM65 and its effects on ACTH production and secretion in ACTH-secreting pituitary cell lines, as well as in murine models using biochemical analyses, confocal microscopy, and luciferase reporter assays.

RESULTS

A novel subtype of PitNETs derived from TPIT lineage cells was identified as with normal TPIT transcription but with lowered protein expression. Furthermore, for the first time, TRIM65 was identified as the E3 ubiquitin ligase of TPIT. Depending on the RING domain, TRIM65 ubiquitinated and degraded the TPIT protein at multiple Lys sites. In addition, TRIM65-mediated ubiquitination of TPIT inhibited POMC transcription and ACTH production to determine the fate of the novel subtype of PitNETs in vitro and in vivo.

CONCLUSION

Our studies provided a novel classification of PitNETs and revealed that the TRIM65-TPIT complex controlled the fate of the novel subtype of PitNETs, which provides a potential therapy target for Cushing's disease.

Hydroxychloroquine overcomes cabergoline resistance in a patient with Lactotroph Pituitary neuroendocrine tumor: a case report

OBJECTIVE

A 22-year-old man complaining erectile dysfunction underwent transsphenoidal surgery for a 2.7 cm sellar mass with total resection and was confirmed at pathology to have a lactotroph pituitary neuroendocrine tumor (PiNET). Postoperatively, the patient's PRL remained at high level and therefore accepted high-dose dopamine receptor agonist (DA) therapy. After over 3 months of bromocriptine (BRC) (15mg/day) and over 3 years of cabergoline (CAB) (3mg/week) therapy, the patient's prolactin (PRL) never achieved long-term normalization. He was diagnosed with DA-resistant lactotroph PitNET.

METHOD

In this study, the patient was given hydroxychloroquine (HCQ) (200 mg/d) and CAB (3 mg/w) in combination for four months. His PRL level was tested by blood test every month.

RESULTS

Taking the combination therapy of HCQ and CAB, the patient's uncontrolled PRL level was normalized within one month and was maintained at the normal level thereafter. Pituitary magnetic resonance imaging (MRI) images with enhancement showed no recurrence. The patient also regained normal sexual function.

DISCUSSION

This is the first report on the combination of HCQ with CAB for the effective treatment of DA-resistant lactotroph pituitary neuroendocrine tumor in a patient, which might provide a novel treatment strategy for clinical management.

Pseudocapsule and pseudocapsule-based extracapsular resection in pituitary neuroendocrine tumors

Since Costello et al. proposed the concept of pseudocapsule of pituitary neuroendocrine tumors (PitNETs) in 1936, many studies have been published on its occurrence, development process, histopathology, and morphology. Pseudocapsule has been proposed as the anatomical interface between PitNETs and normal pituitary gland, therefore the so-called pseudocapsule-based extracapsular resection (ER) technique was developed as an extracapsular surgery method for PitNETs,which differs from the conventional intracapsular resection (IR). In recent years, ER has also been widely used in patients of different tumor types, sizes, and age groups, because the pseudocapsule can be identified more clearly under the endoscopy. Endoscopic transsphenoidal resection for PitNETs has become the preferred surgical method. We reviewed relevant literatures in the past 10 years, showing that ER could achieve better rate of gross total resection (GTR) and biochemical remission, and reduce tumor recurrence than IR, without increasing postoperative complications. Therefore, the pseudocapsule and ER should be valued by neurosurgeons and actively promoted clinically.

Sellar Glomus Tumor Misdiagnosed as Pituitary Adenoma: A Case Report and Review of the Literature

Glomus tumor is a rare mesenchymal tumor with an organ-like structure. Sellar glomus tumors are extremely rare with only six reported cases in the literature. Because of the lack of special clinical manifestations and imaging features, the disorder may be easily misdiagnosed as other sellar tumors, especially pituitary adenomas. Here, the present study showed a case of a 69-year-old male with hypopituitarism who was preliminarily misdiagnosed as non-functional pituitary adenoma.

[Recommendations for diagnosis and treatment of primary biliary cholangitis in China (2021)]

Primary biliary cholangitis is a chronic autoimmune cholestatic disease with a progressive course. This disease is not rare in China, but standardized diagnosis and treatment for primary biliary cholangitis are insufficient. Based on the evidence and guidelines from China and other countries, Rheumatology Branch of Chinese Medical Association developed the recommendations of diagnosis and treatment for primary biliary cholangitis in China. The aim is to help clinicians recognize clinical characters, therapeutic selection and prognosis judgement of primary biliary cholangitis, which will contribute to make diagnosis in time, to select treatment properly and to manage follow-up scientifically.

[Otological and hearing characteristics in children with Turner syndrome]

Objective: To explore the otological and hearing characteristics in children with Turner syndrome (TS), to determine risk factors of hearing loss, and to discuss algorithms for future surveillance. Methods: The clinical data of otolaryngology in children with TS from January 2018 to April 2020 were reviewed retrospectively. A total of 46 female children with TS, aged from 5 to 18 years were enrolled. Karyotypes included 17 cases (37.0%) of monosomy, 16 cases (34.7%) of mosaicism, and 13 cases (28.3%) of abnormal X chromosome structures. The otoscopic characteristics, audiological performance, and otologic diagnoses were evaluated. Multivariate logistic regression and Mann-Whitney U test were used for statistical analysis. Results: The most common otologic comorbidity was otitis media with effusion (OME), including 20 cases (43.5%) with 33 ears (35.9%). 14 cases (30.4%) were diagnosed with hearing loss. The regression analysis revealed that the age (OR=1.345, 95%CI: 1.072-1.760) and comorbidity of OME (OR=9.460, 95%CI: 2.065-60.350) were risk factors associated with hearing loss. In TS with OME, when compared with the mean air conduction threshold, the hearing loss of the group with pars flaccida retractions was significantly higher ((24.3±13.8) dB HL vs. (14.4±4.2) dB HL, U=59.500, P=0.008) than that of the group with none retractions. Conclusion: OME and hearing loss are common in children with TS. As age increases or suffers from OME, the risk of hearing loss increases.

A potential impact of SARS-CoV-2 on pituitary glands and pituitary neuroendocrine tumors

INTRODUCTION

Angiotensin-converting enzyme 2 (ACE2) is the receptor of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The effects of SARS-CoV-2 on normal pituitary glands function or pituitary neuroendocrine tumors (PitNETs) have not yet been elucidated. Thus, the present study aimed to investigate the potential risks of SARS-CoV-2 infection on the impairment of pituitary glands and the development of PitNETs.

METHODS

PitNETs tissues were obtained from 114 patients, and normal pituitary gland tissues were obtained from the autopsy. The mRNA levels of ACE2 and angiotensin II receptor type 1 (AGTR1) were examined by quantitative real-time PCR. Immunohistochemical staining was performed for ACE2 in 69 PitNETs and 3 normal pituitary glands. The primary tumor cells and pituitary cell lines (MMQ, GH3 and AtT-20/D16v-F2) were treated with diminazene aceturate (DIZE), an ACE2 agonist, with various dose regimens. The pituitary hormones between 43 patients with SARS-CoV-2 infection were compared with 45 healthy controls.

RESULTS

Pituitary glands and the majority of PitNET tissues showed low/negative ACE2 expression at both the mRNA and protein levels, while AGTR1 showed high expression in normal pituitary and corticotroph adenomas. ACE2 agonist increased the secretion of ACTH in AtT-20/D16v-F2 cells through downregulating AGTR1. The level of serum adrenocorticotropic hormone (ACTH) was significantly increased in COVID-19 patients compared to normal controls (p < 0.001), but was dramatically decreased in critical cases compared to non-critical patients (p = 0.003).

CONCLUSIONS

This study revealed a potential impact of SARS-CoV-2 infection on corticotroph cells and adenomas.

Knockdown of TRIM32 inhibits tumor growth and increases the therapeutic sensitivity to temozolomide in glioma in a p53-dependent and -independent manner

Tripartite motif protein 32 (TRIM32), an E3 ubiquitin ligase, has been reported to participate in many human cancers. However, the underlying role of TRIM32 in glioma remains largely unknown. Here, we aimed to explore the function of TRIM32 in glioma cells and the clinical implications and found that TRIM32 was upregulated in glioma tissues. Consistently, overexpression of TRIM32 promoted glioma U87 and U251 cell proliferation and conferred cell resistance to temozolomide (TMZ). Conversely, knockdown of TRIM32 inhibited glioma cells proliferation in vitro and in vivo and sensitized glioma cells to the treatment of TMZ in a p53-dependent and -independent manner. Mechanistically, knockdown of TRIM32 induced apoptosis of U87 an U251 cells. In addition, TRIM32 interacted with the antiapoptotic proteins BCL-xL and BCL-w, which antagonized the inhibitory effect of TRIM32 knockdown in U87 cells. Together, our study uncovered the role of TRIM32 in glioma and TRIM32 may be a potential therapeutic target for gliomas.

Lactate-induced M2 polarization of tumor-associated macrophages promotes the invasion of pituitary adenoma by secreting CCL17

Background: Lactate greatly contributes to the regulation of intracellular communication within the tumor microenvironment (TME). However, the role of lactate in pituitary adenoma (PA) invasion is unclear. In this study, we aimed to clarify the effects of lactate on the TME and the effects of TME on PA invasion.

Methods: To explore the correlation between TME acidosis and tumor invasion, LDHA and LAMP2 expression levels were quantified in invasive (n = 32) and noninvasive (n = 32) PA samples. The correlation between immune cell infiltration and tumor invasion was evaluated in 64 PAs. Critical chemokine and key signaling pathway components were detected by qPCR, Western blotting, siRNA knockdown, and specific inhibitors. The functional consequences of CCR4 signaling inhibition were evaluated in vitro and in vivo.

Results: Lactate was positively associated with PA invasion. Of the 64 PA tissues, invasive PAs were related to high infiltration of M2-like tumor-associated macrophages (TAMs) (P < 0.05). Moreover, lactate secreted from PA cells facilitated M2 polarization via the mTORC2 and ERK signaling pathways, while activated TAMs secreted CCL17 to promote PA invasion via the CCL17/CCR4/mTORC1 axis. According to univariate analysis of clinical data, high CCL17 expression was associated with larger tumor size (P = 0.0438), greater invasion (P = 0.0334), and higher susceptibility to postoperative recurrence (P = 0.0195) in human PAs.

Conclusion: This study illustrates the dynamics between PA cells and immune TME in promoting PA invasion via M2 polarization. CCL17 levels in the TME are related to the PA invasiveness and clinical prognosis, and the CCL17/CCR4/mTOCR1 axis may serve as potential therapeutic targets for Pas.

Case Report: Temozolomide Treatment of Refractory Prolactinoma Resistant to Dopamine Agonists

Therapeutic agents for refractory prolactinomas that are resistant to dopamine agonists (DAs) are troublesome, and surgery often only removes a large part of the tumor without complete remission. Among the various second-line treatment regimens, the treatment effect of the alkylating agent temozolomide (TMZ) is only effective for approximately half of patients; however, complete remission is rare. Here we report a patient with prolactinoma who was resistant to high-dose cabergoline (CAB) treatment, demonstrating a continuous increase in both the tumor volume and the prolactin (PRL) level. Given that this case is a refractory prolactinoma, the patient underwent two transsphenoidal approach (TSA) surgeries. The pathological analysis indicated that the Ki-67 index increased significantly from 3% to 30%, and the expression levels of DRD2 and MGMT were low. Finally, TMZ treatment was recommended. A total of six cycles of TMZ standard chemotherapy shrank the tumor volume and the tumor disappeared completely. During the 6-month follow-up period, the tumor did not relapse again, and the PRL level was also normal. RNA sequencing and DNA whole genome sequencing were performed on this prolactinoma specimen, revealing 16 possible gene mutations, including a missense mutation of the PABPC1 gene. Additionally, the copy number variation analysis results showed that several chromosomes had copy number gains compared to the matched peripheral blood sample. In this case, low expression of DRD2 and high proliferation led to resistance to CAB, whereas low MGMT expression contributed to sensitivity to TMZ treatment. The results of genome sequencing still need further investigation at the molecular level to explain the tumor aggressiveness and high sensitivity to TMZ.

Tumor-Associated Macrophages: New Horizons for Pituitary Adenoma Researches

Macrophages are one of the most common infiltrating immune cells and an essential component of tumor microenvironment. Macrophages and the soluble cytokines and chemokines produced play an important role in tumorigenesis, progression, invasion and metastasis in solid tumors. Despite the multiple studies in other solid tumors, there is little known about macrophages in pituitary adenomas. Recently, studies about pituitary adenoma-infiltrated macrophages have been emerging, including the immunohistochemical and immunophenotypic analysis of the pituitary adenomas and further studies into the mechanism of the crosstalk between macrophages and tumor cells in vivo and in vitro. These studies have offered us new insights into the polarization of macrophages and its role in tumorigenesis, progression and invasion of pituitary adenomas. This review describes the advances in the field of pituitary adenoma-infiltrated macrophages and the prospect of targeting macrophages as cancer therapy in pituitary adenoma.

The long noncoding RNA-H19/miRNA-93a/ATG7 axis regulates the sensitivity of pituitary adenomas to dopamine agonists

Dopamine agonists (DAs), such as cabergoline and bromocriptine, are the first-line clinical treatment for prolactinomas. Our previous study demonstrated that long noncoding RNA H19 expression is frequently downregulated in human primary pituitary adenomas and is negatively correlated with tumor progression. However, the significance and mechanism of H19 in the DA treatment of prolactinomas are still unknown. In this study, we reported that H19 had a synergistic effect with DA treatment on prolactinomas in vitro and in vivo. Mechanistically, H19 promoted ATG7 expression in pituitary tumor cells by inhibiting miR-93a expression. In addition, a potential binding site between miR-93 and H19 was confirmed, and low expression of miR-93 was previously found in DA-resistant prolactinomas. Furthermore, we showed that miR-93a regulates ATG7 expression by targeting ATG7 mRNA. In conclusion, our study has identified the role of the H19-miR-93-ATG7 axis in DA treatment of prolactinomas, which may be a potential therapeutic target for human prolactinomas.

Treatment of Pituitary and Other Tumours with Cabergoline: New Mechanisms and Potential Broader Applications

Cabergoline is a dopamine agonist that has been used as the first-line treatment option for prolactin-secreting pituitary adenomas for several decades. It not only suppresses hormone production from these prolactinomas, but also causes tumour shrinkage. Recent studies revealed some novel mechanisms by which cabergoline suppresses tumour cell proliferation and induces cell death. In this article, we review the most recent findings in cabergoline studies, focusing on its anti-tumour function. These studies suggest the potential broader clinical use of cabergoline in the treatment of other tumours such as breast cancer, pancreatic neuroendocrine tumours, and lung cancer.

Multidisciplinary team efforts improve the surgical outcomes of sellar region lesions during pregnancy

PURPOSE

Treatment of space-occupying lesions (SOLs) in the sellar region is a clinical challenge, especially in pregnant women because many treatment decisions are restrained due to pregnancy. We attempt to discuss the surgical indications and timing for pregnant patients and highlight the importance of multidisciplinary team (MDT) treatment.

METHODS

From August 2017 to February 2018, four pregnant women were admitted to our hospital with severe visual impairment due to sellar region SOLs, including two cases of tuberculum sellae meningioma, one case of giant pituitary adenoma and one case of a pituitary abscess. All four patients were safely treated by surgery during the second and third trimesters of pregnancy through concerted efforts of the MDT, including a neurosurgeon as the team leader in combination with experts in obstetrics, ophthalmology and endocrinology.

RESULTS

The SOLs were removed completely from all four patients, resulting in significantly improved vision without operation-related complications. Pregnancy continued postoperatively to full-term delivery in three of the four patients. The other patient with a pituitary abscess selected to terminate the pregnancy at a gestational age of 20 weeks because of her own concerns. The four babies (including a pair of twins) were born healthy and had developed normally at the 6-week postpartum follow-up.

CONCLUSIONS

With the MDT guiding the decision-making process, surgical resection of sellar region SOLs in pregnant women with severe visual impairment is practical to improve the prognosis without affecting the outcomes of pregnancy for either the mother or the infant.

Exosome-Transmitted lncRNA H19 Inhibits the Growth of Pituitary Adenoma

CONTEXT

Our previous study demonstrated that the expression of long noncoding RNA (lncRNA) H19 was frequently downregulated in human primary pituitary adenomas and negatively correlated with tumor progression. However, the role of exosomal lncRNA H19 in the inhibition of pituitary tumor growth remains unclear.

OBJECTIVE

To investigate whether exosomal H19 could be transported across the cell membrane to exert its inhibitory effect on pituitary tumor growth.

DESIGN

Empty lentivirus GH3 cells with or without H19 overexpression were used to establish a xenograft model. Isolated exosomes were identified by transmission electron microscopy, nanoparticle tracking, and Western blotting. The expression levels of serum exosomal H19 from 200 healthy subjects and 206 patients with various subtypes of pituitary tumors were detected by ultracentrifugation and quantitative real-time PCR.

RESULTS

The growth of distal tumor cells was inhibited by transferring exosomal H19, which could be transported through cell membrane and exert its inhibitory effect. Cabergoline increased H19 expression and played a synergic therapeutic effect with exosomal H19. Exosomal H19 inhibited phosphorylation of the mTORC1 substrate 4E-BP1. Of note, the expression level of exosomal H19 in the patients with all subtypes of pituitary tumors was significantly lower than that in the healthy subjects. The change of plasma exosomal H19 level may be correlated with the prognosis or drug response of the patients.

CONCLUSION

Exosomal H19 inhibits the growth of distal pituitary tumors through inhibiting 4E-BP1 phosphorylation. Plasma exosomal H19 may serve as an important biomarker for predicting medical responses of patients with prolactinomas.

DEPTOR inhibits cell proliferation and confers sensitivity to dopamine agonist in pituitary adenoma

DEP domain-containing mechanistic target of rapamycin (mTOR)-interacting protein (DEPTOR) is an important modulator of mTOR, a highly conserved kinase whose hyperactivation is critically involved in a variety of human tumors. The role of DEPTOR playing in pituitary adenoma (PA) is largely unknown. Here, we reported that DEPTOR was downregulated in PA tissues, especially dopamine-resistant prolactinomas. Consistently, overexpression of DEPTOR inhibited pituitary tumor GH3 and MMQ cells proliferation in vitro and in vivo, and sensitized GH3 and MMQ cells to cabergoline (CAB), a dopamine agonist (DA). Conversely, knockdown of DEPTOR promoted GH3 and MMQ cells proliferation, and conferred cells resistance to CAB. Mechanistically, DEPTOR inhibited both mTOR Complex 1 (mTORC1) and 2 (mTORC2) activities in PA cells. In addition, DEPTOR expression level was increased to suppress mTOR kinase activity via decreasing E3 ubiquitin ligase, βTrCP1, in response to CAB. Furthermore, DEPTOR enhanced autophagy-dependent cell death to confer cells sensitivity to CAB. Taken together, our results suggest that DEPTOR may be a potential target for the treatment of PAs.

[Safety and efficacy of DCV-based DAAs therapy for chronic HCV infection in China]

Objective: To evaluate the efficacy and safety of DCV-based DAAs therapy for chronic HCV infected Chinese patients. Methods: An open-label, non-randomized, prospective study was designed. Fifty-two patients with chronic HCV infection were enrolled. Among them, there was one patient after liver transplantation, 2 patients after kidney transplantation, 3 patients with hepatocellular carcinoma, and 4 patients with HBV infection. Thirteen cases with chronic hepatitis C (one compensated cirrhosis) who were negative for resistance-related variants [NS5A RAS (-)] of gene 1b and NS5A were treated with daclatasvir (DCV) + asunaprevir (ASV) for 24 weeks. Twenty-five cases of CHC (six compensated cirrhosis) with GT 1b, 2a, 3a, 3b, 6a were treated with DCV + SOF ± RBV for 24 weeks. 8 cases with decompensated cirrhosis of gene 1b and NS5A RAS(-) were given DCV + SOF + RBV regimen for 12 weeks. Six cases with decompensated cirrhosis, of gene 2a, 1b, 2a, 3a, 3b, were given DCV + SOF + RBV regimen for 24 weeks. HCV RNA, blood routine test, liver and kidney function, and upper abdominal ultrasound/MRI were measured at baseline, 4 weeks of treatment, end of treatment, and 12 weeks of follow-up. The incidence of adverse events and laboratory abnormalities during treatment were recorded. A t-test was used to compare the measurement data between two groups, and analysis of variance was used to compare the measurement data between multiple groups. Results: Sixteen patients (100%) achieved SVR12 after treatment, with 0% recurrence rate. Rapid virological response (RVR) of the four treatment regimens were 76.92%, 54.17%, 87.50%, and 83.33%, respectively, and 32 patients achieved 100% virological response after the completion of treatment. The incidence of adverse events of chronic hepatitis C with cirrhosis and decompensated cirrhosis was 62.5% and 64.29%, respectively. The most common adverse event was fatigue in CHC (25.00%), and elevated indirect bilirubin in decompensated cirrhosis (42.86%). No serious adverse drug events, deaths or adverse reactions occurred. Conclusion: DCV-based DAAs regimen is promising option for the treatment of HCV genotypes, compensated cirrhosis, decompensated cirrhosis, hepatocellular carcinoma, and HCV infection after liver/kidney transplantation in china. Above all, it has high SVR12 with good tolerability and safety profile.

[Improvement and effect analysis of a new neuroendoscopic trans-nasal-sphenoidal pituitary tumor resection approach]

Objective: To modify the individual neuroendoscopic surgical approach of pituitary tumors with specific imaging features, and to analyze the clinical outcomes. Methods: The clinical data of 116 patients with pituitary tumors who underwent surgical treatment at the pituitary tumor diagnosis and treatment center of Ruijin Hospital from April 2014 to December 2017 were collected, then the resection effects and complication rates of pituitary tumors from three different kinds of transsphenoidal approaches (e.g. classical single nostril approach, bilateral approach, "one-and-a-half" approach) were compared. Results: Pituitary tumor resection with "one-and-a-half" trans-nasal-sphenoidal approach achieved the same surgical effects with the bilateral approach, which was difficult to resect with the single-nostril classical approach. And it had significant advantages in the average length of postoperative hospitalization ( "one-and-a-half" : 6.9 days, bilateral: 12.5 days, P<0.01), the average postoperation VAS of olfactory retention ( "one-and-a-half" : 8.6, bilateral: 7.0, P<0.01) and preventing posterior nasal septum perforation (the occurrence rate of "one-and-a-half" : 0%, bilateral: 27%). Conclusion: The "one and a half" approach increases the ability to control and completely resect the lesion beyond the medial edge of the internal carotid artery on the same side of the nostril involving endoscope. It is a good supplement and improvement to the bilateral approach.

Bromocriptine-responsive supersellar germinoma with the expression of dopamine receptors: A case report

BACKGROUND

Germinomas are sensitive to radiotherapy and chemotherapy. However, there has been no report involving in the potential therapeutic effect of dopamine agonists (DAs) such as bromocriptine on germinomas.

CASE DESCRIPTION

A 20-year-old female was presented with bitemporal visual disturbance and amenorrhea. Magnetic resonance imaging demonstrated a huge sellar tumor with upward extension and invasion of the parasellar region. The blood tests showed an exceedingly high level of prolactin. A sellar tumor with hyperprolactinemia was diagnosed, and bromocriptine was initially given. After three months, the tumor volume had been obviously decreased by 82%. However, the tumor re-grew after ten months and the endoscopic endonasal surgery was performed. Histopathological and immunohistochemical examination indicated the patient had a pure sellar germinoma. The tumor cells strongly expressed dopamine 2 receptor and dopamine 5 receptor, which located in the membrane and cytoplasm.

CONCLUSIONS

The transient but significant partial responsiveness of germinoma to bromocriptine treatment in this patient is a novel discovery, suggesting that DAs may be a potential therapeutic choice for tumors with the expression of dopamine 2/5 receptors.

Inhibition of mTORC1 by lncRNA H19 via disrupting 4E-BP1/Raptor interaction in pituitary tumours

Aberrant expression of long noncoding RNA H19 has been associated with tumour progression, but the underlying molecular tumourigenesis mechanisms remain largely unknown. Here, we report that H19 expression is frequently downregulated in human primary pituitary adenomas and is negatively correlated with tumour progression. Consistently, upregulation of H19 expression inhibits pituitary tumour cell proliferation in vitro and tumour growth in vivo. Importantly, we uncover a function of H19, which controls cell/tumour growth through inhibiting function of mTORC1 but not mTORC2. Mechanistically, we show that H19 could block mTORC1-mediated 4E-BP1 phosphorylation without affecting S6K1 activation. At the molecular level, H19 interacted with 4E-BP1 at the TOS motif and competitively inhibited 4E-BP1 binding to Raptor. Finally, we demonstrate that H19 is more effective than cabergoline treatment in the suppression of pituitary tumours. Together, our study uncovered the role of H19-mTOR-4E-BP1 axis in pituitary tumour growth regulation that may be a potential therapeutic target for human pituitary tumours.

LncRNA H19 has been shown to be aberrantly expressed in different cancers. Here, the authors show that H19 lncRNA is downregulated in pituitary adenomas and H19 is able to impede pituitary tumorigenesis via disruption of 4E-BPB1 and Raptor interaction to inhibit the phosphorylation of 4E-BP1.

Cabergoline for the treatment of bromocriptine-resistant invasive giant prolactinomas

PURPOSE

Few studies have specifically focused on the effect of cabergoline on invasive giant prolactinomas (IGPs) resistant to bromocriptine. This study aims to evaluate whether cabergoline could be used as an effective therapy for patients with bromocriptine-resistant IGPs.

METHODS

This retrospective study included 15 patients with bromocriptine-resistant IGPs who received treatment at our department during 2007-2015. Cabergoline was administered in all 15 patients, with the dose adjusted depending on the prolactin response of each patient. Parameters for outcome assessment included prolactin level, pituitary function, tumor size, improvement of the clinical symptoms, visual field defects, drug tolerance, and disease recurrence.

RESULTS

Cabergoline was effective for the treatment of the patients with bromocriptine -resistant IGPs as represented by normalization of the prolactin level in 12/15 patients; improvement or normalization of the pituitary function in 4/5 patients with hypopituitarism; significant reduction in tumor size in 14/15 patients; and relief of the clinical symptoms in 11/15 patients. All 15 patients showed good tolerance to cabergoline. In addition, no recurrence was observed during the mean follow-up period of 63.47 (range 30-145) months.

CONCLUSIONS

Data of this retrospective study demonstrate that cabergoline is an excellent option for the treatment of patients with bromocriptine-resistant IGPs.

[Association between platelet-to-lymphocyte ratio and neutrophil-to-lymphocyte ratio with disease activity in Takayasu arteritis patients]

Objective: To explore the relation between platelet-to-lymphocyte ratio (PLR) or neutrophil-to-lymphocyte ratio (NLR) with disease activity in Takayasu arteritis (TA) patients. Methods: Present retrospective study involved 289 patients with TA, who were hospitalized in our department between January 2010 and October 2017, and 280 age and gender matched healthy controls,who underwent thealth examination in our health examination center during the same period (control group). TA patients were further divided into active and inactive groups (180 and 109 cases respectively) according to Kerr scores. The clinical data were compared between groups. Pearson correlation analysis was used to evaluate the relationship between PLR or NLR and disease activity (Kerr score or C-reactive protein or erythrocyte sedimentation rate). Receiver operating characteristic (ROC) curve was employed to judge the cut-off value of disease activity for TA patients. Results: PLR and NLR were significantly higher in TA group than in control group(137.33 (97.38, 193.37) vs. 120.55 (96.86, 144.60) and 2.38 (1.76, 3.57) vs. 1.66 (1.35, 2.08) , respectively, all P<0.001). PLR and NLR were significantly higher in active TA group than in inactive TA group (163.43 (123.64, 224.15) vs. 110.53 (84.22, 147.24) and 2.59 (1.96, 3.94) vs. 1.95 (1.53, 2.86) respectively, all P<0.001). PLR and NLR of active group were significantly decreased after 6 months treatment (164.05 (123.29, 226.29) vs. 104.67 (77.22, 138.43) and 2.58 (1.96, 3.91) vs. 2.15 (1.67, 2.60) respectively, all P<0.001). PLR was positively correlated with Kerr score (r=0.439, P<0.001), C-reactive protein (r=0.328, P<0.001) and erythrocyte sedimentation rate (r=0.410, P<0.001). NLR also exhibited a positive relationship with Kerr score (r=0.235, P<0.001), C-reactive protein (r=0.169, P=0.005) and erythrocyte sedimentation rate (r=0.123, P=0.037). A PLR level of 176.709 was shown to be the best predictive cut-off value for TA disease activity (sensitivity 44.6%, specificity 93.0%, and area under the curve=0.766).A NLR level of 2.128 was shown to be the best predictive cut-off value for TA disease activity (sensitivity 70.9%, specificity 47.7%, and area under the curve=0.691). Conclusion: PLR and NLR are useful markers for predicting disease activity of TA patients.

[Laryngeal clefts: a review of current literature]

Laryngeal clefts as exceptionally rare congenital anomalies have been reported more and more recently. The clinical symptoms and presentations base on degree of clefts and variety of comorbidities. Mild types of clefts may have minimal clinical impact, whereas severe types may be life-threatening and even lead to death before diagnosis. With more attention of these anomalies and advances in endoscopy, the diagnosis, evaluation and surgery of laryngeal clefts have acquired great improvement, especially International Pediatric Otolaryngology Group(IPOG)have reported consensus guidelines on the diagnosis and management of type Ⅰ laryngeal clefts in 2017. This review of laryngeal clefts may be beneficial to decrease missed diagnosis or misdiagnosis and to achieve individual-based treatment.

Cabergoline versus bromocriptine for the treatment of giant prolactinomas: A quantitative and systematic review

The aim of this study is to compare the efficacy of bromocriptine (BRC) versus cabergoline (CAB) in patients with giant prolactinomas. We searched MEDLINE, EMBASE, CENTRAL and Clinical Trials.gov for studies dated before March 1st, 2016, that used BRC or CAB for the treatment of patients with giant prolactinomas. Specific eligibility criteria were set to identify articles and cases. The selected articles were reviewed, and the data were extracted for analysis. The compared outcomes included tumor shrinkage, tumor response, normalization of prolactin (PRL) level, and visual field defect (VFD) improvement. Gender differences were also considered. Differences between the groups were assessed using Student's t test and the chi-square test. Two hundred and forty-five records were identified, and 10 articles and 104 cases met the inclusion criteria. Based on our analysis, CAB is significantly better than BRC in normalizing PRL levels in patients, especially males, with giant prolactinomas (69.4% versus 31.7%, p = 0.01). However, there was no significant difference between the two drugs in terms of tumor shrinkage, tumor response and VFD improvement (p > 0.05) in male or female patients. CAB exhibits significantly better efficacy than BRC in the normalization of PRL levels in male patients with giant prolactinomas. Regarding tumor reduction and VFD improvement, both drugs are comparably effective for patients of both genders. This quantitative and systematic review provides preliminary evidence in favor of CAB as a medical therapy for treating giant prolactinomas in male patients, especially those with extremely high PRL levels.

Optimal timing of dopamine agonist withdrawal in patients with hyperprolactinemia: a systematic review and meta-analysis

PURPOSE

Dopamine agonists (DAs) are recommended as first-line treatment for patients with hyperprolactinemia. Generally, it is accepted that patients with hyperprolactinemia do not need lifelong medication, but the optimal timing for DA withdrawal has not been determined. The aim of this systematic review and meta-analysis is to assess the impact of DA withdrawal on the clinical outcomes of patients with hyperprolactinemia, and to explore possible factors affecting successful DA withdrawal.

METHODS

The databases of PubMed, Cochrane and EMBASE were searched up to May 2016.

RESULTS

The proportion of patients with persisting normoprolactinemia after DA withdrawal reached 36.6% in a random effects model (95% CI, 29.4-44.2%; I-squared: 82.5%). Data of stratified analysis showed that the success rate of drug withdrawal was high in patients using cabergoline (CAB) as the only treatment (41.2%; 95% CI 32.3-50.4%) and those using CAB over 24 months (48.7%; 95% CI 38.9-58.5%), especially in patients with idiopathic hyperprolactinemia (73.2%; 95% CI 55.6-87.7%). In addition, patients who received a low maintenance dose of CAB, and had a significant reduction in tumor size (over 50%) before withdrawal, were more likely to achieve success (51.5 and 49.4%, respectively).

CONCLUSION

The success rate of DA withdrawal has increased in recent years. Further, the success rate of CAB withdrawal was higher than that of bromocriptine, especially in patients with a duration of treatment longer than 24 months. Conclusively, the probability of success was higher in patients who received low-dose CAB maintenance treatment and those who achieved a significant reduction in tumor size before withdrawal.

Pituitary Tumor Suppression by Combination of Cabergoline and Chloroquine

CONTEXT

The dopamine agonist cabergoline (CAB) has been used widely in the treatment of prolactinomas and other types of pituitary adenomas, but its clinical use is hampered by intolerance in some patients with prolactinoma and lack of effectiveness in other pituitary tumor types. Chloroquine (CQ) is an old drug widely used to treat malaria. Recent studies, including our own, have revealed that CAB and CQ are involved in induction of autophagy and activation of autophagic cell death.

OBJECTIVE

To test whether CAB and CQ can function cooperatively to suppress growth of pituitary adenomas as well as other cancers.

RESULTS

In vitro studies using the rat pituitary tumor cell lines MMQ and GH3, human pituitary tumor cell primary cultures, and several human cancer cell lines showed that CQ enhanced suppression of cell proliferation by CAB. These results were confirmed in in vivo xenograft models in nude mice and estrogen-induced rat prolactinomas. To understand the mechanism of combined CAB and CQ action, we established a low-CAB-dose condition in which CAB was able to induce autophagy but failed to suppress cell growth. Addition of CQ to low-dose CAB blocked normal autophagic cycles and induced apoptosis, evidenced by the further accumulation of p62/caspase-8/LC3-II.

CONCLUSION

The data suggest that combined use of CAB and CQ may increase clinical effectiveness in treatment of human pituitary adenomas, as well as other cancers, making it an attractive option in tumor and cancer therapies.

[Pediatric laryngeal clefts: an experience in the diagnosis and management of 13 cases]

Objective: To investigate the diagnosis and management of laryngeal cleft. Method: The clinical data of 13 cases of laryngeal cleft treated between 2007 and 2015 was analyzed retrospectively. Results: The children with laryngeal cleft were classified according to the classification of Benjamin-Inglis, as type Ⅰ(11 cases), typeⅡ(1 case) and type Ⅲ(1 case). All patients were confirmed by microlaryngobronchoscopy under general anaesthetic. Eleven typeⅠ and 1 type Ⅱ clefts were managed conservatively, with which all type Ⅰ patients were successfully managed, while the type Ⅱ patient was resolved by surgical endoscopy. The type Ⅲ patient was treated by open repair but the results was poor. Conclusions: Patients who suffered with choking on feeding or recurrent aspiration pneumonia, especially coexisted with other congenital malformation, needed detailed evaluation for laryngeal cleft, although which was a rare congenital abnormality. Electronic laryngoscope could be the first step to screen the cleft, while microlaryngobronchoscopy is the gold standard for diagnosis of laryngeal cleft. The majority of children with lower type clefts can be managed conservatively. Surgical endoscopy has high success rate when strictly following the indication. Type Ⅲ and Ⅳ clefts have high mortality for usually combining with severe complications and abnormalities.

Activation of DRD5 (dopamine receptor D5) inhibits tumor growth by autophagic cell death

Dopamine agonists such as bromocriptine and cabergoline have been successfully used in the treatment of pituitary prolactinomas and other neuroendocrine tumors. However, their therapeutic mechanisms are not fully understood. In this study we demonstrated that DRD5 (dopamine receptor D5) agonists were potent inhibitors of pituitary tumor growth. We further found that DRD5 activation increased production of reactive oxygen species (ROS), inhibited the MTOR pathway, induced macroautophagy/autophagy, and led to autophagic cell death (ACD) in vitro and in vivo. In addition, DRD5 protein was highly expressed in the majority of human pituitary adenomas, and treatment of different human pituitary tumor cell cultures with the DRD5 agonist SKF83959 resulted in growth suppression, and the efficacy was correlated with the expression levels of DRD5 in the tumors. Furthermore, we found that DRD5 was expressed in other human cancer cells such as glioblastomas, colon cancer, and gastric cancer. DRD5 activation in these cell lines suppressed their growth, inhibited MTOR activity, and induced autophagy. Finally, in vivo SKF83959 also inhibited human gastric cancer cell growth in nude mice. Our studies revealed novel mechanisms for the tumor suppressive effects of DRD5 agonists, and suggested a potential use of DRD5 agonists as a novel therapeutic approach in the treatment of different human tumors and cancers.

Enhanced toxicity to the cyanobacterium Microcystis aeruginosa by low-dosage repeated exposure to the allelochemical N-phenyl-1-naphthylamine

It has been puzzling whether and how a plant could exert a strong allelopathic inhibition to the target organisms by releasing low concentrations of allelochemicals. Plant allelochemicals have been proposed to be released continuously, however, direct evidence from specific allelochemicals is urgently required. In the present study, the toxicity of allelochemical N-phenyl-1-naphthylamine (NPN) towards the cyanobacterium Microcystis aeruginosa by two different exposure patterns was compared. One was low-dosage repeated exposure (LRE), in which 50  μg L^-1 NPN was repeatedly dosed to simulate the continual release of allelochemicals, and the other one was high-dosage single exposure (HSE) as per the routine toxicity assay. The results showed a significant growth inhibition to M. aeruginosa in the LRE group, where the inhibition rate reached above 90% from day 6 to day 9. The cell-membrane damage ratio increased from 64.05% on day 5 up to 96.60% on day 9. PSII photosynthesis activity expressed as Fv/Fm, Φ_PSII, NPQ and ETRmax was also thoroughly inhibited in this group. Whereas the growth and PSII photosynthesis activity of M. aeruginosa in the HSE group were inhibited initially, but recovered gradually from day 4 or 5, which was accompanied by a continuous reduction of NPN content in culture solutions. Although NPN content in the LRE group was relatively lower, it remained at a more stable level throughout the experiment. These results indicate that continual release of low-dosage allelochemicals by aquatic plants plays crucial roles in their potent inhibition against cyanobacteria. Low-dosage continual exposure pattern needs to be investigated further.

[Causes and management of pediatric spontaneous tonsillar haemorrhage]

Objective: To analyze the causes and management plan of pediatric spontaneous tonsillar haemorrhage(STH). Methods: According to the criteria of STH difined by Griffies, patients with STH from December 2013 to January 2016 were included in this retrospective study. Results: A total of 11 patients were reviewed. The etiological diagnosis included 3 pediatric Epstein-Barr virus associated infectious mononucleosis(EBV-IM), 3 suspected pediatric EBV-IM to 3 acute suppurative tonsillitis, 1 acute viral tonsillitis and 1 hemophilia A. The management strategies included antiviral, antibacteria, transfusion, surgical examination followed with bipolar coagulation hemostasis under general anesthesia. No patient treated with tosillectomy. Conclusions: STH is now a rare condition, the causes of which in child are more or less different from adult.This emergency can be treated in time if a detailed management plan for pediatric STH is formulated.