Altered microRNA profiles during early colon adenoma progression in a porcine model of familial adenomatous polyposis

MicroRNA-98: the multifaceted regulator in human cancer progression and therapy

MicroRNA-98 (miR-98) stands as an important molecule in the intricate landscape of oncology. As a subset of microRNAs, these small non-coding RNAs have accompanied a new era in cancer research, underpinning their significant roles in tumorigenesis, metastasis, and therapeutic interventions. This review provides a comprehensive insight into the biogenesis, molecular properties, and physiological undertakings of miR-98, highlighting its double-edged role in cancer progression-acting both as a tumor promoter and suppressor. Intriguingly, miR-98 has profound implications for various aspects of cancer progression, modulating key cellular functions, including proliferation, apoptosis, and the cell cycle. Given its expression patterns, the potential of miR-98 as a diagnostic and prognostic biomarker, especially in liquid biopsies and tumor tissues, is explored, emphasizing the hurdles in translating these findings clinically. The review concludes by evaluating therapeutic avenues to modulate miR-98 expression, addressing the challenges in therapy resistance, and assessing the efficacy of miR-98 interventions. In conclusion, while miR-98's involvement in cancer showcases promising diagnostic and therapeutic avenues, future research should pivot towards understanding its role in tumor-stroma interactions, immune modulation, and metabolic regulation, thereby unlocking novel strategies for cancer management.

MicroRNA expression associated with low-grade cervical intraepithelial neoplasia outcomes

PURPOSE

Only a fraction of low-grade cervical intraepithelial neoplasia (CIN) progresses to high-grade CIN; however, the biological processes that differentiate progressive CIN from CIN that resolves naturally are poorly understood. MicroRNAs (miRNAs) are important epigenetic regulators of gene expression and thus, miRNA expression profiling can reveal the dysregulated biology underlying disease processes. The purpose of this case-control study was to reveal miRNA expression patterns and predict the underlying biological pathways that are associated with clinical outcomes of low-grade CIN.

METHODS

Women with low-grade CIN diagnosis and definitive clinical outcomes (n = 51) were identified retrospectively using electronic clinical records. Comprehensive miRNA expression profiling was performed on the low-grade CIN diagnostic cervical biopsies retrieved from pathology archives. Differential miRNA expression was analyzed by comparing women with CIN that progressed to women with CIN that resolved naturally.

RESULTS

Differential expression of 29 miRNAs was observed in low-grade CIN that progressed to high-grade compared to low-grade CIN that resolved. Of these, 24 were significantly downregulated in progressive CIN, including miR-638, miR-3196, miR-4488, and miR-4508, while 5 miRNAs, including miR-1206a, were significantly upregulated. Computational gene ontology analysis based on the discovered miRNAs and their putative mRNA targets revealed biological processes associated with oncogenic phenotypes.

CONCLUSION

Distinct miRNA expression profiles are associated with clinical outcomes of low-grade CIN. The functional effects of the differentially expressed miRNAs may be biological determinants of CIN progression or resolution.

Use of Translational, Genetically Modified Porcine Models to Ultimately Improve Intestinal Disease Treatment

For both human and veterinary patients, non-infectious intestinal disease is a major cause of morbidity and mortality. To improve treatment of intestinal disease, large animal models are increasingly recognized as critical tools to translate the basic science discoveries made in rodent models into clinical application. Large animal intestinal models, particularly porcine, more closely resemble human anatomy, physiology, and disease pathogenesis; these features make them critical to the pre-clinical study of intestinal disease treatments. Previously, large animal model use has been somewhat precluded by the lack of genetically altered large animals to mechanistically investigate non-infectious intestinal diseases such as colorectal cancer, cystic fibrosis, and ischemia-reperfusion injury. However, recent advances and increased availability of gene editing technologies has led to both novel use of large animal models in clinically relevant intestinal disease research and improved testing of potential therapeutics for these diseases.

LncRNA-PANDAR regulates the progression of thyroid carcinoma by targeting miR-637/KLK4

Thyroid gland carcinoma (TC) originates from follicular or parafollicular thyroid cells and is one of the most common endocrine organ malignancies. To explore the molecular mechanism by which long-chain non-coding RNAs regulate the growth and metastasis of thyroid gland carcinoma, in this study we focused on long non-coding RNAs (lncRNAs) that have been reported to be involved in tumorigenesis. We identified Promoter Region of CDKN 1A antisense DNA damage-activated RNA (PANDAR), which was positively correlated with thyroid gland carcinoma risk. PANDAR could promote thyroid gland carcinoma cell proliferation and metastasis. PANDAR negatively correlated with miR-637, and miR-637 overexpression suppressed thyroid gland carcinoma progression, which could be reversed by PANDAR. MiR-637 could target Kallikrein-related peptidases 4 (KLK4) to inhibit its expression, which was high in thyroid gland carcinoma. KLK4 inhibited cell progression in thyroid gland carcinoma cells. Knockdown of PANDAR expression inhibited cancer progression in nude mice. Overall, PANDAR can suppress miR-637 and induce KLK4 to regulate invasion and migration in thyroid gland carcinoma. Additionally, we identified miR-637 as a target of PANDAR in thyroid gland carcinoma, and PANDAR can be used as a novel therapeutic target for the treatment of thyroid gland carcinoma.

Porcine pancreatic ductal epithelial cells transformed with KRASG12D and SV40T are tumorigenic

We describe our initial studies in the development of an orthotopic, genetically defined, large animal model of pancreatic cancer. Primary pancreatic epithelial cells were isolated from pancreatic duct of domestic pigs. A transformed cell line was generated from these primary cells with oncogenic KRAS and SV40T. The transformed cell lines outperformed the primary and SV40T immortalized cells in terms of proliferation, population doubling time, soft agar growth, transwell migration and invasion. The transformed cell line grew tumors when injected subcutaneously in nude mice, forming glandular structures and staining for epithelial markers. Future work will include implantation studies of these tumorigenic porcine pancreatic cell lines into the pancreas of allogeneic and autologous pigs. The resultant large animal model of pancreatic cancer could be utilized for preclinical research on diagnostic, interventional, and therapeutic technologies.

Polymorphisms of CSF1R and WISP1 genes are associated with severity of familial adenomatous polyposis in APC1311 pigs

Hereditary familial adenomatous polyposis (FAP) in humans significantly increases the risk of development of colorectal cancer (CRC). Germline mutations in the APC (adenomatous polyposis coli) gene are responsible for FAP. Despite having the same causative mutation, the severity of the disease differs from patient to patient. The porcine FAP model carrying a truncating APC¹³¹¹ mutation, orthologous to the dominant human mutation that leads to severe form of the disease (APC¹³⁰⁹), mirrors the severity of polyposis. Earlier RNAseq studies have revealed the differential expression of WISP1 and CSF1R in samples derived from low-grade (LG-IEN) and more advanced high-grade (HG-IEN) colon polyps of APC^1311/+ pigs. The grade of dysplasia was correlated with the severity of polyposis in APC^1311/+ pigs characterized by a low (LP) and high (HP) numbers of polyps. The goal of this work was to find DNA variants that regulate the expression of CSF1R and WISP1 in LP and HP pigs. In total, 32 and 36 polymorphisms in CSF1R and WISP1 were found, respectively. Of these, the genotype frequency of four silent SNPs in the coding region of WISP1 differed significantly between LP and HP lines. In silico analysis revealed an elevated minimum free energy (MFE) for three of these SNPs, suggesting their role in mRNA structure stability. Furthermore, four polymorphisms in the promoter region of CSF1R, cosegregating as a common haplotype, were associated with polyp number in APC^1311/+ pigs. A secreted alkaline phosphatase (SEAP) assay showed, however, that these variants have no direct effect on the activity of the CSF1R promoter. Concluding, our study identified polymorphisms in CSF1R and WISP1 that are potentially associated with the severity of polyposis in APC^1311/+ pigs.

Genetically Engineered Pigs to Study Cancer

Recent decades have seen groundbreaking advances in cancer research. Genetically engineered animal models, mainly in mice, have contributed to a better understanding of the underlying mechanisms involved in cancer. However, mice are not ideal for translating basic research into studies closer to the clinic. There is a need for complementary information provided by non-rodent species. Pigs are well suited for translational biomedical research as they share many similarities with humans such as body and organ size, aspects of anatomy, physiology and pathophysiology and can provide valuable means of developing and testing novel diagnostic and therapeutic procedures. Porcine oncology is a new field, but it is clear that replication of key oncogenic mutation in pigs can usefully mimic several human cancers. This review briefly outlines the technology used to generate genetically modified pigs, provides an overview of existing cancer models, their applications and how the field may develop in the near future.

The expression of TAP1 candidate gene, but not its polymorphism and methylation, is associated with colonic polyp formation in a porcine model of human familial adenomatous polyposis

In humans, the dysfunction of the adenomatous polyposis coli (APC) gene causes hereditary familial adenomatous polyposis (FAP) and increased risk of colorectal cancer (CRC). The severity of polyposis varies between individuals, but genetic basis for this is in large part unknown. This variability also occurs in our porcine model of FAP, based on an APC¹³¹¹ mutation (orthologous to human APC¹³⁰⁹). Since loss of TAP1 function can lead to CRC in humans, we searched for germline polymorphisms in APC^1311/+ pigs with low (LP) and high (HP) levels of polyposis, as well as in wild-type pigs representing six breeds and a commercial line. The distribution of 40 identified polymorphic variants was similar in the LP and HP pigs. In contrast, the TAP1 transcript level was significantly higher in normal colon mucosa of HP pigs than in LP pigs. Moreover, six SNPs showed significant effects on TAP1 promoter activity, but no correlation with severity of polyposis was observed. Analysis of DNA methylation in the promoter region showed that one CpG site differed significantly between LP and HP pigs. We conclude that TAP1 genotype may not itself be associated with polyposis, but our findings concerning its expression suggest a role in the development of polyps.

Association between LINC00657 and miR-106a serum expression levels and susceptibility to colorectal cancer, adenomatous polyposis, and ulcerative colitis in Egyptian population

Colorectal cancer (CRC) represented the second cause of mortality among cancer patients. Long noncoding RNAs and microRNAs (miRNAs) serve as noninvasive biomarkers for CRC surveillance and introduce new therapeutic approaches. LINC00657 and miR-106a expression levels play a pivotal role in CRC. This study included 190 Egyptian subjects, and the expression levels of LINC00657 and miR-106a in serum were measured by using quantitative real-time polymerase chain reaction. We found that upregulation of LINC00657 and downregulation of miR-106a are significantly associated with the development of CRC. Also, a positive correlation was detected between their serum levels. In addition, serum LINC00657 can distinguish adenomatous polyposis (AP) patients and/or ulcerative colitis (UC) patients from controls. Also the miRNA-106a expression level discriminates AP but not UC from healthy individuals. Our study cited new diagnostic biomarkers for CRC, AP, and UC among Egyptians in addition to be noninvasive screening tools for CRC in both healthy subjects and those having precancerous lesions. © 2019 IUBMB Life, 71(9):1322-1335, 2019.

MiR-let-7e inhibits invasion and magration and regulates HMGB1 expression in papillary thyroid carcinoma

Thyroid cancer keeps rapidly increasing worldwide and the most frequent type is papillary thyroid carcinoma (PTC). MicroRNAs (miRNAs) are proved dysregulated in many types of malignancies, including thyroid cancer. Although miR-let-7e has been implicated in several types of cancer regulation, relatively little is known about the function of miR-let-7e in PTC. In this study, we showed that the overexpression of miR-let-7e or knockdown of high mobility group box 1 (HMGB1) inhibited cell migration and invasion. MiR-let-7e downregulates HMGB1 expression by directly targeting the HMGB1 3'-UTR. Furthermore, HMGB1 reintroduction reversed the anti-proliferation, anti-migration, and anti-invasion roles of miR-let-7e. miR-let-7e might function as a tumor suppressor in papillary thyroid carcinoma through HMGB1. Therefore, our study demonstrates that miR-let-7e plays an important role in papillary thyroid carcinoma progression and might represent a new potential therapeutic target for treatment.

Altered miRNA-4321 expression in maternal and foetal placenta of intrauterine growth restricted bovine foetuses

Intrauterine growth restriction (IUGR) is a serious pregnancy complication caused by placental insufficiency. We previously reported that truncation of MIMT1 gene exons 3 and 4 (MIMT1^Del) causes IUGR in cattle. Here we investigated miRNA expression in the foetal and maternal placenta tissues of MIMT1^Del/WT foetuses. Small RNA next generation sequencing and quantitative PCR revealed placental tissue-specific expression of the miR-4321, known to regulate many genes involved in early foetal development. This study also indicated that maternal and foetal components of the placenta respond differently to a deleterious conceptus mutation.

Elevated expression of p53 in early colon polyps in a pig model of human familial adenomatous polyposis

Familial adenomatous polyposis (FAP) is a hereditary predisposition to formation of colon polyps that can progress to colorectal cancer (CRC). The severity of polyposis varies substantially within families bearing the same germline mutation in the adenomatous polyposis coli (APC) tumour suppressor gene. The progressive step-wise accumulation of genetic events in tumour suppressor genes and oncogenes leads to oncogenic transformation, with driver alterations in the tumour protein p53 (TP53) gene playing a key role in advanced stage CRC. We analysed groups of pigs carrying a truncating mutation in APC (APC^1311/+; orthologous to human APC^1309/+) to study the influence of TP53 polymorphisms and expression on the frequency of polyp formation and polyp progression in early-stage FAP. Five generations of APC^1311/+ pigs were examined by colonoscopy for polyposis severity and development. A total of 19 polymorphisms were found in 5'-flanking, coding, and 3' untranslated regions of TP53. The distribution of TP53 genotypes did not differ between APC^1311/+ pigs with low (LP) and high (HP) number of colon polyps. p53 mRNA expression was analysed in distally located normal mucosa samples of wild-type pigs, APC^1311/+ LP and HP pigs, and also in distally located polyp samples histologically classified as low-grade (LG-IEN) and high-grade intraepithelial dysplastic (HG-IEN) from APC^1311/+ pigs. p53 mRNA expression was found to be significantly elevated in HG-IEN compared to LG-IEN samples (p = 0.012), suggesting a role for p53 in the early precancerous stages of polyp development.