Comprehensive quantitative analysis of alternative splicing variants reveals the HNF1B mRNA splicing pattern in various tumour and non-tumour tissues

Hepatocyte nuclear factor-1-beta (HNF1B) is a transcription factor and putative biomarker of solid tumours. Recently, we have revealed a variety of HNF1B mRNA alternative splicing variants (ASVs) with unknown, but potentially regulatory, functions. The aim of our work was to quantify the most common variants and compare their expression in tumour and non-tumour tissues of the large intestine, prostate, and kidney. The HNF1B mRNA variants 3p, Δ7, Δ7–8, and Δ8 were expressed across all the analysed tissues in 28.2–33.5%, 1.5–2%, 0.8–1.7%, and 2.3–6.9% of overall HNF1B mRNA expression, respectively, and occurred individually or in combination. The quantitative changes of ASVs between tumour and non-tumour tissue were observed for the large intestine (3p, Δ7–8), prostate (3p), and kidney samples (Δ7). Decreased expression of the overall HNF1B mRNA in the large intestine and prostate cancer samples compared with the corresponding non-tumour samples was observed (p = 0.019 and p = 0.047, respectively). The decreased mRNA expression correlated with decreased protein expression in large intestine carcinomas (p < 0.001). The qualitative and quantitative pattern of the ASVs studied by droplet digital PCR was confirmed by next-generation sequencing, which suggests the significance of the NGS approach for further massive evaluation of the splicing patterns in a variety of genes.

A Maturity-Onset Diabetes of The Young (MODY) 5 Young Woman With HNF1B Heterozygosity Missing Based On 17q12 Recurrent Deletion Syndrome

Maturity-onset diabetes of the young type 5 (MODY5) is a rare subtype of MODYs. It caused by mutations of the hepatocyte nuclear factor 1 homeobox b gene (HNF1B). A 21-year-old young woman was admitted to our hospital for severe malnutrition and gastrointestinal symptoms. At age 20, she was diagnosed with type 2 diabetes mellitus and was administered with oral antidiabetic drugs. Soon afterwards, the patient discontinued the medication on her own accord, and then went to the hospital again due to diabetic ketoacidosis. After insulin treatment, diabetic ketoacidosis was cured and blood glucose was controlled satisfactorily. But intractable nausea, vomiting and persistent weight loss was stubborn. Further examination revealed that the patient had hypokalemia and hard rectification hypomagnesemia. Genetic testing revealed about 1.85Mb heterozygous fragment deletion on chromosome 17 and deletion of exons 1-9 of HNF1B heterozygosity missing was approved. Finally, the patient was diagnosed MODY 5 with HNF1B heterozygosity missing based on 17q12 recurrent deletion syndrome. Key words: Maturity-onset diabetes of the young 5 (MODY5), Hepatocyte nuclear factor 1 homeobox b gene (HNF1B), 17q12 Recurrent deletion syndrome

Characterization of aquaporin1b (AQP1b) mRNA in mud loach (Misgurnus mizolepis) in response to heavy metal and immunostimulant stimuli

Aquaporins (AQPs) facilitate the transport of water or other small solutes into cells in the presence of osmotic gradients. However, the current understanding of piscine AQP gene with cellular stress responses has been still limitedly exemplified. In present study, we characterized the mud loach AQP1b gene at the nucleotide and amino acid levels. We identified three AQP 1b transcript variants (mmAQP1b_tv1, mmAQP1b_tv2, and mmAQP1b_tv3). Then, we examined the AQP1b promoter region and observed several transcription factor binding sites (TFBS) for nuclear factor of activated T-cells (NFAT), SRY-box, c-AMP responsive element binding protein (CREB), GATA binding factor, and hepatic nuclear factor-1. Interestingly, mmAQP1b transcription was differentially modulated by heavy metal or immunostimulant challenge. Further studies to deepen the knowledge of fish AQP-mediated adaptation response potentially relevant to molecular pathogenesis are warranted.Summary statementWe identified mud loach AQP1b transcript variants and consensus sequences involved in stress or innate immunity in promotor region. AQP1b transcription was differentially modulated by heavy metal or immunostimulant challenge.

The Expression of Transcription Factors in Fetal Lamb Kidney

(1) Background: Renal development involves frequent expression and loss of transcription factors, resulting in the activation of genes. Wilms’ tumor 1 (WT1), hepatocyte nuclear factor-1-beta (HNF1β), and paired box genes 2 and 8 (Pax2 and Pax8) play an important role in renal development. With this in vivo study, we examined the period and location of expression of these factors in renal development. (2) Methods: Fetal lamb kidneys (50 days from gestation to term) and adult ewe kidneys were evaluated by hematoxylin and eosin staining. Serial sections were subjected to immunohistochemistry for WT1, HNF1β, Pax2, and Pax8. (3) Results: Pax2, Pax8, and HNF1β expression was observed in the ureteric bud and collecting duct epithelial cells. We observed expression of WT1 alone in metanephric mesenchymal cells, glomerular epithelial cells, and interstitial cells in the medullary rays and Pax8 and HNF1β expression in tubular epithelial cells. WT1 was highly expressed in cells more proximal to the medulla in renal vesicles and in C- and S-shaped bodies. Pax2 was expressed in the middle and peripheral regions, and HNF1β in cells in the region in the middle of these. (4) Conclusions: WT1 is involved in nephron development. Pax2, Pax8, and HNF1β are involved in nephron maturation and the formation of peripheral collecting ducts from the Wolffian duct.

Acquired Evolution of Mitochondrial Metabolism Regulated by HNF1B in Ovarian Clear Cell Carcinoma

Clear cell carcinoma (CCC) of the ovary exhibits a unique morphology and clinically malignant behavior. The eosinophilic cytoplasm includes abundant glycogen. Although the growth is slow, the prognosis is poor owing to resistance to conventional chemotherapies. CCC often arises in endometriotic cysts and is accompanied by endometriosis. Based on these characteristics, three clinical questions are considered: why does ovarian cancer, especially CCC and endometrioid carcinoma, frequently occur in endometriotic cysts, why do distinct histological subtypes (CCC and endometrioid carcinoma) arise in the endometriotic cyst, and why does ovarian CCC possess unique characteristics? Mutations in AT-rich interacting domain-containing protein 1A and phosphatidylinositol-4,5-Bisphosphate 3-Kinase Catalytic Subunit alpha genes may contribute to the carcinogenesis of ovarian CCC, whereas hepatocyte nuclear factor-1-beta (HNF1B) plays crucial roles in sculpting the unique characteristics of ovarian CCC through metabolic alterations. HNF1B increases glutathione synthesis, activates anaerobic glycolysis called the Warburg effect, and suppresses mitochondria. These metabolic changes may be induced in stressful environments. Life has evolved to utilize and control energy; eukaryotes require mitochondria to transform oxygen reduction into useful energy. Because mitochondrial function is suppressed in ovarian CCC, these cancer cells probably acquired further metabolic evolution during the carcinogenic process in order to survive stressful environments.

Human transcription factor protein interaction networks

In participation of transcriptional regulation, transcription factors (TFs) interact with several other proteins. Here, we identified 7233 and 2176 protein-protein interactions for 110 different human TFs through proximity-dependent biotinylation (BioID) and affinity purification mass spectrometry (AP-MS), respectively. The BioID analysis resulted more high-confident interactions, highlighting the transient and dynamic nature of many of the TF interactions. Using clustering and correlation analyses, we identified subgroups of TFs associated with specific biological functions, such as RNA-splicing, actin signalling or chromatin remodeling. We also observed 203 TF-TF interactions, of which 175 were interactions with Nuclear Factor 1 (NFI) -family members, indicating uncharacterized cross-talk between NFI signalling and numerous other TF signalling. Moreover, TF interactions with basal transcription machinery were mainly observed through TFIID and SAGA complexes. This study, not only, provides a rich resource of human TF interactions, but also act as starting point directing future studies aimed at understanding TF mediated transcription.

Hepatocyte nuclear factor 1 alpha influences pancreatic cancer growth and metastasis

Hepatocyte nuclear factor 1 homeobox alpha (HNF1α) is a transcription factor involved in endodermal organogenesis and pancreatic precursor cell differentiation and development. Earlier studies have reported a role for HNF1α in pancreatic ductal adenocarcinoma (PDAC) but it is controversial. The mechanism by which it impacts PDAC is yet to be explored in depth. In this study, using the online databases we observed that HNF1α is upregulated in PDAC, which was also confirmed by our immunohistochemical analysis of PDAC tissue microarray. Silencing HNF1α reduced the proliferative, migratory, invasive and colony forming capabilities of pancreatic cancer cells. Key markers involved in these processes (pPI3K, pAKT, pERK, Bcl2, Zeb, Snail, Slug) were significantly changed in response to alterations in HNF1α expression. On the other hand, overexpression of HNF1α did not induce any significant change in the aggressiveness of pancreatic cancer cells. Our results demonstrate that reduced expression of HNF1α leads to inhibition of pancreatic cancer growth and progression, which indicates that it could be a potential oncogene and target for PDAC.