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Introduction: The molecular programs regulating human pancreatic endocrine cell induction and fate allocation are not well deciphered. Here, we investigated the spatiotemporal expression pattern and the function of the neurogenic differentiation factor 2 (NEUROD2) during human endocrinogenesis. Methods: Using Crispr-Cas9 gene editing, we generated a reporter knock-in transcription factor (TF) knock-out human inducible pluripotent stem cell (iPSC) line in which the open reading frame of both NEUROD2 alleles are replaced by a nuclear histone 2B-Venus reporter (NEUROD2nVenus/nVenus). Results: We identified a transient expression of NEUROD2 mRNA and its nuclear Venus reporter activity at the stage of human endocrine progenitor formation in an iPSC differentiation model. This expression profile is similar to what was previously reported in mice, uncovering an evolutionarily conserved gene expression pattern of NEUROD2 during endocrinogenesis. In vitro differentiation of the generated homozygous NEUROD2nVenus/nVenus iPSC line towards human endocrine lineages uncovered no significant impact upon the loss of NEUROD2 on endocrine cell induction. Moreover, analysis of endocrine cell specification revealed no striking changes in the generation of insulin-producing b cells and glucagon-secreting a cells upon lack of NEUROD2. Discussion: Overall, our results suggest that NEUROD2 is expendable for human b cell formation in vitro. [ABSTRACT FROM AUTHOR]

BACKGROUND: Renal cell carcinoma (RCC) is the most common and malignant tumor of kidney tissue, with unknown molecular mechanism and pathogenesis. Recent studies have demonstrated that micro ribonucleic acids (miRNAs) may have potential role in initiation and progression of RCC. In this study we evaluated expression patterns of two RNA molecules, miR-625 and miR-302a in tumor and non-tumor portions of RCC samples. METHODS: The relative expression levels of miR-625 and miR-302a were delineated by real-time PCR in 20 formalin-fixed paraffinembedded (FFPE) RCC samples and compared with 20 non-tumor matched samples obtained from margins of the same samples. RESULTS: We found approximately 15-fold increase in miR-625 expression in tumor samples compared to non-tumor samples of each patient, but it was not a significant difference (P Value: 0.097). On the other hand, miR-302a expression was similar between tumor and non-tumor sections of the sample (P Value > 0.05). Additionally, we did not find an association between age, gender, grade and stage of tumors, and expression level of either of the two miRNAs. CONCLUSION: Our data demonstrated that there is no significant difference of miR-625 and miR-302a expression in tumor samples of RCC when compared to non-tumor samples. We further found no relationship between clinico-pathological characteristics and expression levels of miR-625 or miR-302a. [ABSTRACT FROM AUTHOR]

Objective(s): Similar characteristics of molecular pathways between cellular reprogramming events and tumorigenesis have been accentuated in recent years. Reprogramming-related transcription factors, also known as Yamanaka factors (OCT4, SOX2, KLF4, and c-MYC), are also well-known oncogenes promoting cancer initiation, progression, and cellular transformation into cancer stem cells. Long non-coding RNAs (lncRNAs) are a major class of RNA molecules with emerging roles in stem cell pluripotency, cellular reprogramming, cellular transformation, and tumorigenesis. The long intergenic non-coding RNA ROR (lincRNA-ROR, linc-ROR) acts as a regulator of cellular reprograming through sponging miR-145 that normally negatively regulates the expression of the stemness factors NANOG, OCT4, and SOX2. Materials and Methods: Here, we employed a real-time PCR approach to determine the expression patterns of linc-ROR and its two novel spliced variants (variants 2 and 4) in esophageal squamous cell carcinoma (ESCC). Results: The quantitative real-time RT-PCR results revealed a significant up-regulation of linc-ROR (P=0.0098) and its variants 2 (P=0.0250) and 4 (P=0.0002) in tumor samples of ESCC, compared to their matched non-tumor tissues obtained from the margin of same tumors. Our data also demonstrated a significant up-regulation of variant 4 in high-grade tumor samples, in comparison to the low-grade ones (P=0.04). Moreover, the ROC curve analysis demonstrated that the variant 4 of ROR has a potential to discriminate between tumor and non-tumor samples (AUC=0.66, P<0.05). Conclusion: Our data suggest a significant up-regulation of linc-ROR and its variants 2 and 4 in ESCC tissue samples. [ABSTRACT FROM AUTHOR]

Background: The human OCT4 gene, responsible for pluripotency and self-renewal of Embryonic Stem (ES) and Embryonic Carcinoma (EC) cells, can generate several transcripts (OCT4A, OCT4B-variant 2, OCT4B-variant 3, OCT4B-variant 5, OCT4B1, OCT4 B2 and OCT4B3) by alternative splicing and alternative promoters. OCT4A that is responsible for ES and EC cell stemness properties is transcribed from a promoter upstream of Exon1a in those cells. The OCT4B group variants (OCT4B-variant2, OCT4Bvariant3, OCT4B-variant5, OCT4B1, OCT4B2 and OCT4B3) are transcribed from a different promoter located in intron 1 and some of them respond to the cell stresses, but cannot sustain the ES/EC cell self-renewal. However, the exact function of OCT4B group variants is still unclear. Methods: In the present study, we employed RT-PCR and sequencing approaches to explore different forms of OCT4 transcripts. Results: Our data revealed that the OCT4B group variants (OCT4B-variant2, OCT4 B-variant3, OCT4B1, OCT4B2 and OCT4B3) have longer 5' UTR in the human bladder carcinoma cell line of 5637. Conclusion: These OCT4 variants undergo alternative splicing in their 5' UTR which might exert regulatory roles in transcription and translation mechanisms. [ABSTRACT FROM AUTHOR]

Objectives: Similar characteristics of molecular pathways between cellular reprogramming events and tumorigenesis have been accentuated in recent years. Reprogramming-related transcription factors, also known as Yamanaka factors (OCT4, SOX2, KLF4, and c-MYC), are also well-known oncogenes promoting cancer initiation, progression, and cellular transformation into cancer stem cells. Long non-coding RNAs (lncRNAs) are a major class of RNA molecules with emerging roles in stem cell pluripotency, cellular reprogramming, cellular transformation, and tumorigenesis. The long intergenic non-coding RNA ROR (lincRNA-ROR, linc-ROR) acts as a regulator of cellular reprograming through sponging miR-145 that normally negatively regulates the expression of the stemness factors NANOG, OCT4, and SOX2., Materials and Methods: Here, we employed a real-time PCR approach to determine the expression patterns of linc-ROR and its two novel spliced variants (variants 2 and 4) in esophageal squamous cell carcinoma (ESCC)., Results: The quantitative real-time RT-PCR results revealed a significant up-regulation of linc-ROR ( P =0.0098) and its variants 2 ( P =0.0250) and 4 ( P =0.0002) in tumor samples of ESCC, compared to their matched non-tumor tissues obtained from the margin of same tumors. Our data also demonstrated a significant up-regulation of variant 4 in high-grade tumor samples, in comparison to the low-grade ones ( P =0.04). Moreover, the ROC curve analysis demonstrated that the variant 4 of ROR has a potential to discriminate between tumor and non-tumor samples ( AUC =0.66, P <0.05)., Conclusion: Our data suggest a significant up-regulation of linc-ROR and its variants 2 and 4 in ESCC tissue samples.