Tumor-suppressive effects of atelocollagen-conjugated hsa-miR-520d-5p on un-differentiated cancer cells in a mouse xenograft model

Current Achievements and Applications of Transcriptomics in Personalized Cancer Medicine

Over the last decades, transcriptome profiling emerged as one of the most powerful approaches in oncology, providing prognostic and predictive utility for cancer management. The development of novel technologies, such as revolutionary next-generation sequencing, enables the identification of cancer biomarkers, gene signatures, and their aberrant expression affecting oncogenesis, as well as the discovery of molecular targets for anticancer therapies. Transcriptomics contribute to a change in the holistic understanding of cancer, from histopathological and organic to molecular classifications, opening a more personalized perspective for tumor diagnostics and therapy. The further advancement on transcriptome profiling may allow standardization and cost reduction of its analysis, which will be the next step for transcriptomics to become a canon of contemporary cancer medicine.

Role of non-coding RNA in pancreatic cancer

Pancreatic cancer is a malignant disease that develops rapidly and carries a poor prognosis. Currently, surgery is the only radical treatment. Non-coding RNAs (ncRNAs) are protein-free RNAs produced by genome transcription; they play important roles in regulating gene expression, participating in epigenetic modification, cell proliferation, differentiation and reproduction. ncRNAs also play key roles in the development of cancer; microRNA (miRNA) and long non-coding RNA (lncRNA) may lead the way to new treatments for pancreatic cancer. miRNAs are short-chain ncRNAs (19–24 nt) that inhibit the degradation of protein translation or their target gene mRNAs to regulate gene expression. lncRNAs contain >200 nt of ncRNA and play important regulatory roles in a number of malignant tumors, in terms of tumor cell proliferation, apoptosis, invasion and distant metastasis. lncRNAs can be exploited for the diagnosis and treatment of pancreatic cancer and have substantial prospects for clinical application. Nevertheless, the molecular mechanism of their regulation and function, as well as the significance of other ncRNAs, such as piwi-interacting RNA, in the pathogenesis of pancreatic cancer, are largely unknown. In this review, the structures of ncRNAs with various classifications, as well as the functions and important roles of ncRNAs in the diagnosis and treatment of pancreatic cancer are reviewed.

miR-520d-5p can reduce the mutations in hepatoma cancer cells and iPSCs-derivatives

Background

Human microRNAs (miRNAs) have diverse functions in biology, and play a role in nearly every biological process. Here we report that miR-520d-5p (520d-5p) causes undifferentiated cancer cells to adopt benign or normal status in vivo in immunodeficient mice via demethylation and P53 upregulation. Further we found that 520-5p causes normal cells to elongate cellular lifetime and mesenchymal stem cell-like status with CD105 positivity. We hypothesized that ectopic 520d-5p expression reduced mutations in undifferentiated type of hepatoma (HLF) cells through synergistic modulation of methylation-related enzymatic expression.

Methods

To examine whether there were any changes in mutation status in cells treated with 520d-5p, we performed next generation sequencing (NGS) in HLF cells and human iPSC-derivative cells in pre-mesenchymal stem cell status. We analyzed the data using both genome-wide and individual gene function approaches.

Results

520d-5p induced a shift towards a wild type or non-malignant phenotype, which was regulated by nucleotide mutations in both HLF cells and iPSCs. Further, 520d-5p reduced mutation levels in both the whole genome and genomic fragment assemblies.

Conclusions

Cancer cell genomic mutations cannot be repaired in most contexts. However, these findings suggest that applied development of 520d-5p would allow new approaches to cancer research and improve the quality of iPSCs used in regenerative medicine.

Electronic supplementary material

The online version of this article (10.1186/s12885-019-5786-y) contains supplementary material, which is available to authorized users.

SIRP Alpha Protein Downregulates in Human Astrocytoma: Presumptive Involvement of Hsa-miR-520d-5p and Hsa-miR-520d-3p

Astrocytomas are the most common brain tumors with poor survival in malignant forms. Signal regulatory protein alpha (SIRP alpha) is a transmembrane protein expressed on immune cells and macrophages and is reported to modulate tumor cell phagocytosis. In the present study, we investigated the involvement of miR-520d-5p and miR-520d-3p in regulation of SIRP alpha expression. Here, we report mRNA and protein expression profile of SIRP alpha in 39 surgically resected human astrocytoma tissue samples and 14 control brain tissue samples. Transcript expression pattern was studied by real-time PCR while Western blotting and immunohistochemistry were used to evaluate protein expression. Expression profile of miR-520d-5p and miR-520d-3p was studied by real-time PCR. Computational prediction was employed to analyze the binding of miR-520d-5p and miR-520d-3p for SIRP alpha mRNA. It is evident from preliminary investigation that SIRP alpha transcripts are expressed in control brain tissues, increased in low-grade (grade II) tumor tissues, and decreased with further grade progression (P < 0.05). SIRP alpha protein was moderately expressed in control brain tissues but under-expressed in low- and high-grade tissue samples (P < 0.05). Immunohistochemistry results further confirmed Western blot outcomes. Computational prediction supplemented with 3' and 5'UTR targeting analysis and correlation studies reveals that hsa-miR-520d-5p (P = 0.028, R ² = 0.94) (95 % CI 0.15 to 0.99) and hsa-miR-520d-3p (P = 0.027, R ² = 0.94) (95% CI 0.17 to 0.99) may be the putative microRNAs involved in regulation of SIRP alpha protein expression. Real-time PCR expression profile depicts that mature form of both miRNAs is significantly overexpressed in low-grade (GII) tumor tissue samples compared to control and high-grade (GIII and GIV) tissue samples. MiR-520d-5p and miR-520d-3p were found with expression pattern similar to SIRP alpha transcripts. We show that SIRP alpha protein is under-expressed in low and high grades of astrocytoma patients' tissue samples. Control brain tissues were found to be positive with SIRP alpha protein expression. Real-time PCR expression analysis confirms that miR-520d-5p and miR-520d-3p expression levels were significantly correlated with SIRP alpha transcripts in control, low-grade, and high-grade tissue samples. Computational prediction further evidenced for binding sites of these miRNAs on 3' and 5'UTR of SIRP alpha transcripts. Taken together, we predict that miR-520d-5p and miR-520d-3p may be having role in the regulation of under-expressed SIRP alpha protein expression.