A bioinformatics-based approach and expression assay for identification of dysregulated genes in pituitary adenoma

Non-functioning pituitary adenomas (NFPAs) are a group of pituitary neuroendocrine tumors that are associated with morbidity. The exact pathophysiological process leading to this pathology is not known. Nerve growth factor (NGF) is a neurotropic factor that might be involved in this process. We used bioinformatics tools to analyze expression of genes in NFPA samples. Our analyses led to identification of NGF-related genes, namely ARC, ID1, and SH3GL3 - as well as one long non-coding RNA (lncRNA) called myocardial infarction associated transcript (MIAT). Then, we assessed their expression in NFPAs and their adjacent non-cancerous samples. While expression levels of SH3GL3 and MIAT were different between NFPA samples and control samples, expressions of ARC and ID1 were not meaningfully different between these two groups of specimens. SH3GL3 was over-expressed in NFPA samples compared with control samples (expression ratio (95% CI)= 8.22 (1.51-44.6), P value= 0.03). Similarly, expression of MIAT was higher in NFPAs compared with controls (expression ratio (95% CI)= 7.7 (1.7-33.6), P value= 0.009). Taken together, we validated the bioinformatics results regarding the expression of SH3GL3 and MIAT. This study provides a deeper understanding of the involvement of these genes in the pituitary tumorigenesis.

Upregulation of MAPKAPK5-AS1, PXN-AS1 and URB1-AS1 lncRNAs in non-functioning pituitary adenoma

Long non-coding RNAs (lncRNAs) have been shown to be dysregulated in a variety of malignant and non-malignant lesions including non-functioning pituitary adenomas (NFPAs). In the current experimental study, we have selected six lncRNAs, namely MAPKAPK5-AS1, NUTM2B-AS1, ST7-AS1, LIFR-AS1, PXN-AS1 and URB1-AS1 to assess their expression in a cohort of Iranian patients with NFPA. MAPKAPK5-AS1, PXN-AS1 and URB1-AS1 were shown to be over-expressed in NFPA tissues compared with control samples (Expression ratios (95% CI) = 10 (3.94-25.36), 11.22 (4.3-28.8) and 9.33 (4.12-21.12); p values < 0.0001, respectively). The depicted ROC curves showed the AUC values of 0.73, 0.80 and 0.73 for MAPKAPK5-AS1, PXN-AS1 and URB1-AS1, respectively. Relative expression level of PXN-AS1 was associated with tumour subtype (p value = 0.49). Besides, relative expression levels of MAPKAPK5-AS1 and LIFR-AS1 were associated with gender of patients (p values = 0.043 and 0.01, respectively). Cumulatively, the current study indicates the possible role of MAPKAPK5-AS1, PXN-AS1 and URB1-AS1 lncRNAs in the pathogenesis of NFPAs.

Surgical anatomic findings of sphenoid sinus in 1009 Iranian patients with pituitary adenoma undergoing endoscopic transsphenoidal surgery

OBJECTIVE

The most common surgical technique for the management of pituitary adenomas is the endoscopic endonasal transsphenoidal approach (EEA). preoperative neuroimaging along with detecting surgical landmarks of the sphenoid sinus during surgery is important for making a successful operation.

METHOD

This study includes 1009 patients with pituitary adenomas who underwent EEA between 2013 and 2020. We evaluated the anatomical features of the sphenoid sinus through a panel of items obtained from imaging and intra-operative findings.

RESULTS

Our result includes 57.38% nonfunctional, 8.42% cushing, 12.39% prolactinoma, and 21.8% acromegaly patients who had undergone endoscopic endonasal transsphenoidal surgery. The mean age of the patients was 45 with a male to female ratio of 1.2:1. Sellar sphenoid type was the most common (91.8%) with only 12% symmetrical inter sphenoid septa, Internal carotid artery dehiscence was found in 1.7% of the cases. Apoplexy was present in 6.3% of patients, which was found more prevalent in nonfunctional adenomas (9.67%, Odds ratio: 4.85, 95% CI 2.24-11.79) and further investigation revealed a significant association between apoplexy and sphenoid mucosal edema and hemorrhage (Odds ratio: 43.0, 95% CI 22.50-84.26), and between apoplexy and cystic lesions (OR = 4.14, 95% CI 1.87-8.45, P-value < 0.0001). Acromegaly is associated with the increased number of lateral recces (Odds ratio: 11.41, 95% CI 7.54-17.52), septation of the sphenoid sinus (Marginal mean: 3.92, 95% CI 3.69-4.14), edematous sinonasal mucosa (Odds ratio: 6.7; 95% CI 4.46-10.08), and higher bony (OR: 4.81, 95% CI 2.60-8.97, P-value < 0.001) and cavernous (OR: 1.7, 95% CI 1.13-2.46, P-value < 0.01) invasion.

CONCLUSION

The present study provides anatomical data about the sphenoid sinus and its adjacent vital structures with adenomal specific changes that are necessary to prevent complications during endoscopic advanced transsphenoidal surgery.

CircMTO1: A circular RNA with roles in the carcinogenesis

Circular RNAs (circRNAs) have a closed loop structure which endows them high stability. These transcripts are made through back splicing instead of classical splicing and are abundant in the human transcriptome. Recent advances in the development and implementation of high-throughput sequencing methods in cooperation with novel bioinformatics tools have shown contribution of circRNAs in the developmental processes, physiological settings and pathoetiology of cancers. CircMTO1 is a circRNA which was firstly identified as a down-regulated circRNA in hepatocellular carcinoma through circRNA profiling using microarray technique. Subsequent independent studies in lung adenocarcinoma, colorectal cancer, bladder cancer, glioblastoma, prostate cancer, osteosarcoma, gastric cancer and ovarian cancer have verified down-regulation of circMTO1 in neoplastic tissues compared with non-neoplastic ones. However, expression of circMTO1 has been found to be up-regulated in cervical and gallbladder cancers. miR-17, miR-9, miR-221, miR-6893, miR-92, miR-219a-5p, miR-337, miR-630, miR-3200-5p and miR-199a-3p have been shown to be sequestered by circMTO1. This circRNA can regulate activity of Notch, Wnt/β-Catenin, TGF-β/Smad, JAK1/STAT3 and AMPK signaling pathways. In the current study, we review the literature on the role of circMTO1 in the tumorigenesis.