MicroRNAs that regulate PTEN as potential biomarkers in colorectal cancer: a systematic review

Semiquantitative assessment of phosphatase and tensin homolog value with immunohistochemistry in colorectal cancer

INTRODUCTION

Colorectal cancer has emerged as a concerning health problem, ranking the third most common form of cancer in both men and women. The phosphatase and tensin homologue (PTEN) protein is widely known for its role as an inhibitor of the phosphatidylinositol 3-kinase/protein kinase-B/mammalian target of rapamycin (PI3K/Akt/mTOR) pathway, playing a major role inhibiting tumor development. Previous studies investigated the role of this protein in the PI3K pathway and how it affected colorectal cancer. However, a standardized cut-off value for PTEN expression has not been established.

METHODS

Immunohistochemistry was used in examining PTEN. The staining grade ranging from 0 to 3 was then multiplied by the number of 100 cancer cells counted, with total score between 0 and 300. In this study, receiver operating characteristic (ROC) curve was employed to determine the expression cut-off value for PTEN in colorectal cancer.

RESULTS

This study showed statistically significant results (P < 0.001) in either tumor or non-tumor tissues by using the ROC curve with a cut-off value of 199.0. This study also revealed significant correlation between nodal status with PTEN (P = 0.008) and stage with PTEN (P = 0.019) with sensitivity 0.753 and specificity 0.728.

CONCLUSION

Semiquantitative assessment with cell counting multiplied by color intensity is a good method in determining PTEN expression. The use of immunohistochemical staining intensity and cell scoring with ROC cut-off is effective to elaborate the effects of PTEN in colorectal cancer (PTEN value > 199.0 was classified as strong and ≤ 199.0 as weak).

Molecular functions of microRNAs in colorectal cancer: recent roles in proliferation, angiogenesis, apoptosis, and chemoresistance

MiRNAs (microRNAs) constitute a group of diminutive molecules of non-coding RNA intricately involved in regulating gene expression. This regulation is primarily accomplished through the binding of miRNAs to complementary sequences situated in the 3'-UTR of the messenger RNA (mRNA) target; as a result, they are degraded or repressed. The multifaceted biogenesis of miRNAs is characterized by a meticulously orchestrated sequence of events encompassing transcription, processing, transportation, and decay. Colorectal cancer stands as a pervasive and formidable ailment, afflicting millions across the globe. Colorectal cancer is not well diagnosed early, and metastasis rates are high, which results in low survival rates in advanced stages. The genesis and progression of colorectal cancer are subject to the influence of genetic and epigenetic factors, among which miRNAs play a pivotal role. When it comes to colorectal cancer, miRNAs have a dual character, depending on the genes they target, functioning as either tumor suppressors or oncogenes and the prevailing cellular milieu. Their impact extends to modulating critical facets of colorectal cancer pathogenesis, including proliferation, angiogenesis, apoptosis, chemoresistance, and radiotherapy response. The discernible potential of miRNAs which are used as biomarkers to diagnose colorectal cancer, prognosis, and treatment response has come to the forefront. Notably, miRNAs are easily found and detected readily in a variety of biological fluids, including saliva, blood, urine, and feces. This prominence is attributed to the inherent advantages of miRNAs over conventional biomarkers, including heightened stability, specificity, sensitivity, and accessibility. Various investigations have pinpointed miRNA signatures or panels capable of differentiating colorectal cancer patients from their healthy counterparts, predicting colorectal cancer stage and survival, and monitoring colorectal cancer recurrence and therapy response. Although there has been research on miRNAs in various diseases, there has been less research on miRNAs in cancer. Moreover, updated results of preclinical and clinical studies on miRNA biomarkers and drugs are required. Nevertheless, the integration of miRNAs as biomarkers for colorectal cancer is not devoid of challenges and limitations. These encompass the heterogeneity prevalent among colorectal cancer subtypes and stages, the variability in miRNA expression across different tissues and individuals, the absence of standardized methodologies for miRNA detection and quantification, and the imperative for validation through extensive clinical trials. Consequently, further research is imperative to conclusively establish the clinical utility and reliability of miRNAs as colorectal cancer biomarkers. MiR-21 demonstrates carcinogenic characteristics by targeting several tumor suppressor genes, which encourages cell division, invasion, and metastasis. On the other hand, by controlling the Wnt/β-catenin pathway, the tumor suppressor miRNA miR-34a prevents CRC cell proliferation, migration, and invasion. Furthermore, in colorectal cancer, the miR-200 family increases chemotherapy sensitivity while suppressing epithelial-mesenchymal transition (EMT). As an oncogene, the miR-17-92 cluster targets elements of the TGF-β signaling pathway to encourage the growth of CRC cells. Finally, miR-143/145, which is downregulated in CRC, influences apoptosis and the progression of the cell cycle. These miRNAs affect pathways like Wnt, TGF-β, PI3K-AKT, MAPK, and EMT, making them potential clinical biomarkers and therapeutic targets. This review summarizes recent research related to miRNAs, their role in tumor progression and metastasis, and their potential as biomarkers and therapeutic targets in colorectal cancer. In addition, we combined miRNAs' roles in tumorigenesis and development with the therapy of CRC patients, leading to novel perspectives on colorectal cancer diagnosis and treatment.

Vitexin enhances radiosensitivity of mouse subcutaneous xenograft glioma by affecting the miR-17-5p/miR-130b-3p/PTEN/HIF-1α pathway

PURPOSE

Vitexin can cooperate with hyperbaric oxygen to sensitize the radiotherapy of glioma by inhibiting the hypoxia-inducible factor (HIF)-1α. However, whether vitexin has a direct radiosensitization and how it affects the HIF-1α expression remain unclear. This study investigated these issues.

METHODS

The SU3 cells-inoculated nude mice were divided into control, radiation, and vitexin + radiation groups. The vitexin + radiation-treated mice were intraperitoneally injected with 75 mg/kg vitexin daily for 21 days. On the 3rd, 10th, and 17th days during the vitexin treatment, the radiation-treated mice were locally irradiated with 10 Gy, respectively. In vitro, the microRNA (miR)-17-5p or miR-130b-3p mimics-transfected SU3 cells were used to examine the effects of vitexin plus radiation on expression of miR-17-5p- or miR-130b-3p-induced radioresistance-related pathway proteins. The effects of vitexin on miR-17-5p and miR-130b-3p expression in SU3 cells were also evaluated.

RESULTS

Compared with the radiation group, the tumor volume, tumor weight, and expression of HIF-1α, vascular endothelial growth factor, and glucose transporter-1/3 proteins, miR-17-5p, and miR-130b-3p in tumor tissues in the vitexin + radiation group decreased, whereas the expression of phosphatase and tensin homolog (PTEN) protein increased. After treatment of miR-17-5p or miR-130b-3p mimics-transfected SU3 cells with vitexin plus radiation, the PTEN protein expression also increased, the HIF-1α protein expression decreased correspondingly. Moreover, vitexin decreased the miR-17-5p and miR-130b-3p expression in SU3 cells.

CONCLUSION

Vitexin can enhance the radiosensitivity of glioma, and its mechanism may partly be related to the attenuation of HIF-1α pathway after lowering the inhibitory effect of miR-17-5p and miR-130b-3p on PTEN.

Cancer-associated fibroblasts drive colorectal cancer cell progression through exosomal miR-20a-5p-mediated targeting of PTEN and stimulating interleukin-6 production

BACKGROUND

This study evaluated the clinical relevance of a set of five serum-derived circulating microRNAs (miRNAs) in colorectal cancer (CRC). Additionally, we investigated the role of miR-20a-5p released by exosomes derived from cancer-associated fibroblasts (CAFs) in the context of CRC.

METHODS

The expression levels of five circulating serum-derived miRNAs (miR-20a-5p, miR-122-5p, miR-139-3p, miR-143-5p, and miR-193a-5p) were quantified by real-time quantitative PCR (RT-qPCR), and their associations with clinicopathological characteristics in CRC patients were assessed. The diagnostic accuracy of these miRNAs was determined through Receiver Operating Characteristic (ROC) curve analysis. CAFs and normal fibroblasts (NFs) were isolated from tissue samples, and subsequently, exosomes derived from these cells were isolated and meticulously characterized using electron microscopy and Western blotting. The cellular internalization of fluorescent-labeled exosomes was visualized by confocal microscopy. Gain- and loss-of-function experiments were conducted to elucidate the oncogenic role of miR-20a-5p transferred by exosomes derived from CAFs in CRC progression. The underlying mechanisms were uncovered through luciferase reporter assay, Western blotting, enzyme-linked immunosorbent assays, as well as proliferation and migration assays.

RESULTS

The expression levels of serum-derived circulating miR-20a-5p and miR-122-5p were significantly higher in CRC and were positively correlated with advanced stages of tumorigenesis and lymph node metastasis (LNM). In contrast, circulating miR-139-3p, miR-143-5p, and miR-193a-5p were down-regulated in CRC and associated with early tumorigenesis. Except for miR-139-3p, they showed a negative correlation with LNM status. Among the candidate miRNAs, significantly elevated levels of miR-20a-5p were observed in both cellular and exosomal fractions of CAFs. Our findings indicated that miR-20a-5p induces the expression of EMT markers, partly by targeting PTEN. Exosomal miR-20a secreted by CAFs emerged as a key factor enhancing the proliferation and migration of CRC cells. The inhibition of miR-20a impaired the proliferative and migratory potential of CAF-derived exosomes in SW480 CRC cells, suggesting that the oncogenic effects of CAF-derived exosomes are mediated through the exosomal transfer of miR-20a. Furthermore, exosomes originating from CAFs induced increased nuclear translocation of the NF-kB p65 transcription factor in SW480 CRC cells, leading to increased interleukin-6 (IL-6) production.

CONCLUSIONS

We established a set of five circulating miRNAs as a non-invasive biomarker for CRC diagnosis. Additionally, our findings shed light on the intricate mechanisms underpinning the oncogenic impacts of CAF-derived exosomes and underscore the pivotal role of miR-20a-5p in CRC progression.

Overview of miR-106a Regulatory Roles: from Cancer to Aging

MicroRNAs (miRNAs) comprise a class of non-coding RNA with extensive regulatory functions within cells. MiR-106a is recognized for its super-regulatory roles in vital processes. Hence, the analysis of its expression in association with diseases has attracted considerable attention for molecular diagnosis and drug development. Numerous studies have investigated miR-106 target genes and shown that this miRNA regulates the expression of some critical cell cycle and apoptosis factors, suggesting miR-106a as an ideal diagnostic and prognostic biomarker with therapeutic potential. Furthermore, the reported correlation between miR-106a expression level and cancer drug resistance has demonstrated the complexity of its functions within different tissues. In this study, we have conducted a comprehensive review on the expression levels of miR-106a in various cancers and other diseases, emphasizing its target genes. The promising findings surrounding miR-106a suggest its potential as a valuable biomolecule. However, further validation assessments and overcoming existing limitations are crucial steps before its clinical implementation can be realized.

Membrane-associated RING-CH protein (MARCH8) is a novel glycolysis repressor targeted by miR-32 in colorectal cancer

BACKGROUND

Colorectal cancer (CRC) is the third most common cancer and leading cause of cancer-related deaths worldwide. Aberrant cellular metabolism is a hallmark of cancer cells, and disturbed metabolism showed clinical significance in CRC. The membrane-associated RING-CH 8 (MARCH8) protein, the first MARCH E3 ligase, plays an oncogenic role and serves as a prognostic marker in multiple cancers, however, the role of MARCH8 in CRC is unclear. In the present study, we aimed to investigate the biomarkers and their underlying mechanism for CRC.

METHOD

In this study, we first examined the function of MARCH8 in CRC by analysing public database. Besides, we performing gene silencing studies and generating cellular overexpression and xenograft models. Then its protein substrate was identified and validated. In addition, the expression of MARCH8 was investigated in tissue samples from CRC patients, and the molecular basis for decreased expression was analysed.

RESULTS

Systematic analysis reveals that MARCH8 is a beneficial prognostic marker in CRC. In CRC, MARCH8 exhibited tumor-suppressive activity both in vivo and in vitro. Furthermore, we found that MARCH8 is negatively correlated with hexokinase 2 (HK2) protein in CRC patients. MARCH8 regulates glycolysis and promotes ubiquitination-mediated proteasome degradation to reduces HK2 protein levels. Then HK2 inhibitor partially rescues the effect of MARCH8 knockdown in CRC. Poised chromatin and elevated miR-32 repressed MARCH8 expression.

CONCLUSION

In summary, we propose that in CRC, poised chromatin and miR-32 decrease the expression of MARCH8, further bind and add ubiquitin, induce HK2 degradation, and finally repress glycolysis to promote tumor suppressors in CRC.

Repetitive Sequence Transcription in Breast Cancer

Repetitive sequences represent about half of the human genome. They are actively transcribed and play a role during development and in epigenetic regulation. The altered activity of repetitive sequences can lead to genomic instability and they can contribute to the establishment or the progression of degenerative diseases and cancer transformation. In this work, we analyzed the expression profiles of DNA repetitive sequences in the breast cancer specimens of the HMUCC cohort. Satellite expression is generally upregulated in breast cancers, with specific families upregulated per histotype: in HER2-enriched cancers, they are the human satellite II (HSATII), in luminal A and B, they are part of the ALR family and in triple-negative, they are part of SAR and GSAT families, together with a perturbation in the transcription from endogenous retroviruses and their LTR sequences. We report that the background expression of repetitive sequences in healthy tissues of cancer patients differs from the tissues of non-cancerous controls. To conclude, peculiar patterns of expression of repetitive sequences are reported in each specimen, especially in the case of transcripts arising from satellite repeats.

miRNAs as cornerstones in colorectal cancer pathogenesis and resistance to therapy: A spotlight on signaling pathways interplay - A review

Colorectal cancer (CRC) is the world's third most prevalent cancer and the main cause of cancer-related mortality. A lot of work has been put into improving CRC patients' clinical care, including the development of more effective methods and wide biomarkers variety for prognostic, and diagnostic purposes. MicroRNAs (miRNAs) regulate a variety of cellular processes and play a significant role in the CRC progression and spread via controlling their target gene expression by translation inhibition or mRNA degradation. Consequently, dysregulation and disruption in their function, miRNAs are linked to CRC malignant pathogenesis by controlling several cellular processes involved in the CRC. These cellular processes include increased proliferative and invasive capacity, cell cycle aberration, evasion of apoptosis, enhanced EMT, promotion of angiogenesis and metastasis, and decreased sensitivity to major treatments. The miRNAs control cellular processes in CRC via regulation of pathways such as Wnt/β-catenin signaling, PTEN/AKT/mTOR axis, KRAS, TGFb signaling, VEGFR, EGFR, and P53. Hence, the goal of this review was to review miRNA biogenesis and present an updated summary of oncogenic and tumor suppressor (TS) miRNAs and their potential implication in CRC pathogenesis and responses to chemotherapy and radiotherapy. We also summarise the biological importance and clinical applications of miRNAs in the CRC.

Regulatory network identified by pulmonary transcriptome and proteome profiling reveals extensive change of tumor-related genes in microRNA-21 knockout mice

PURPOSE

MicroRNA-21 (miR-21) is a well-known oncomiR and plays key roles in regulating various biological processes related to pulmonary diseases, especially lung carcinoma. The regulatory roles and downstream targets of miR-21 remain far from well understood. We aimed to identify miR-21-gene regulatory network in lung tissue.

METHODS

Transcriptome and proteome analyses were performed on lung tissues from miR-21 knockout (KO) mice and their wildtype (WT) littermates. Differentially expressed genes (DEGs) and proteins (DEPs) between miR-21KO and WT were analyzed, and correlation analysis was performed between transcriptional and translational level. DEPs were used for prediction of miR-21 target genes and construction of co-expression network.

RESULTS

Comparing with WT mice, 820 DEGs and 623 DEPs were identified in lung tissues of miR-21KO mice. Upregulated DEGs and DEPs were both significantly enriched in pathways of metabolism of xenobiotics by cytochrome P450, drug metabolism, and chemical carcinogenesis. Of the 31 molecules commonly identified in DEGs and DEPs, 9 upregulated genes were tumor suppressor genes while 8 downregulated genes were oncogenes, and 12 genes showed closely positive correlation between mRNA and protein expression. Real-time PCR validation results were consistent with the omics data. Among the upregulated DEPs in miR-21KO mice, 21 genes were predicted as miR-21 targets. The miR-21 regulatory network was constructed by target genes and their highly co-expressed proteins, which identified the miR-21 target Itih4 as a hub gene.

CONCLUSION

MiR-21-gene regulatory network was constructed in mouse lung tissue. MiR-21KO resulted in extensive upregulation of tumor suppressor genes and downregulation of oncogenes.

Necdin, one of the important pathway proteins in the regulation of osteosarcoma progression by microRNA-200c

MicroRNA-200c (miR-200c) generally acts as a tumor suppressor in multiple cancer types and a promising therapeutic target in tumorigenesis. However, only a few studies have explained the role of miR-200c in the development of osteosarcoma (OS). In this study, we investigated the role of miR-200c in OS progression and identified the regulatory pathway protein NDN involved in inhibiting the occurrence and development of OS. Firstly, we found that miR-200c is downregulated in OS cells and tissues. As well, in vitro and in vivo experiments showed that upregulating miR-200c inhibits the proliferation, invasion, metastasis of Saos-2 cells, promotes the apoptosis of Saos-2 cells and suppresses tumor growth in mice, indicating miR-200c plays a major role in regulating the OS progression. Furthermore, bioinformatics analysis showed that an anti-tumor protein, necdin (NDN), might be a potential target by miR-200c. To verify this hypothesis, we measured the expression level of NDN in OS cells and tissues and found NDN is downregulated, suggesting NDN is functional in OS progression. Moreover, we found that the expression levels of NDN and miR-200c in in vivo and in vitro experiments were positively correlated. However, the results of dual-luciferase reporter gene experiment showed miR-200c does not directly act on the 3ʹ untranslated region (UTR) of NDN gene, indicating that NDN might be an important pathway protein which regulates OS progression in the presence of miR-200c. Therefore, miR-200c/NDN could be potential targets for developing effective treatment against OS.

Phytochemicals mediated modulation of microRNAs and long non-coding RNAs in cancer prevention and therapy

MicroRNAs (miRNAs) and long noncoding RNAs (lncRNAs) are two main categories of noncoding RNAs (ncRNAs) that can influence essential biological functions in various ways, as well as their expression and function are tightly regulated in physiological homeostasis. Additionally, the dysregulation of these ncRNAs seems to be crucial to the pathogenesis of human diseases. The latest findings indicate that ncRNAs execute vital roles in cancer initiation and progression, and the cancer phenotype can be reversed by modulating their expression. Available scientific discoveries suggest that phytochemicals such as polyphenols, alkaloids, terpenoids, and organosulfur compounds can significantly modulate multiple cancer-associated miRNAs and lncRNAs, thereby inhibiting cancer initiation and development. However, despite promising outcomes of experimental research, only a few clinical trials are currently being conducted to evaluate the therapeutic effectiveness of these compounds. Nevertheless, understanding phytochemical-mediated ncRNA regulation in cancer and the underlying molecular mechanisms on tumor pathophysiology can aid in the development of novel therapeutic strategies to combat this deadly disease.

RNA-binding protein RBM38 inhibits colorectal cancer progression by partly and competitively binding to PTEN 3'UTR with miR-92a-3p

RNA-binding motif protein 38 (RBM38) belongs to the RNA recognition motif family of RNA-binding proteins (RBPs). RBM38 was previously identified to suppress tumorigenesis in colorectal cancer (CRC). RBM38 was also reported to bind to the 3'UTR of phosphatase and tensin homolog gene on chromosome 10 (PTEN), a tumor suppressor involved in many cellular processes, to stabilize PTEN transcripts. In the present study, we investigated the mechanisms underlying the regulation of RBM38 in CRC. Reverse transcription quantitative polymerase chain reaction and western blotting detected the expression of RBM38, PTEN, and miR-92a-3p. Colony formation, EdU, sphere formation, Transwell invasion, and in vivo assays examined the influence of RBM38 on CRC progression. Furthermore, RNA immunoprecipitation (RIP) assay determined the binding site of RBM38 on PTEN 3'UTR. The binding of miR-92a-3p or RBM38 on PTEN 3'UTR was assessed by luciferase reporter and RIP assays. We discovered that RBM38 was downregulated in CRC cells and tissues. RBM38 repressed CRC progression in vitro and in vivo. Furthermore, RBM38 upregulated and stabilized PTEN expression. Interestingly, the overexpression of PTEN reversely attenuated the promotion of RBM38 depletion on CRC progression. Additionally, RBM38 competed with miR-92a-3p in binding to PTEN 3'UTR. In conclusion, RBM38 inhibits CRC progression by competitively binding to PTEN 3'UTR with miR-92a-3p.

Hypoxia Enhances Activity and Malignant Behaviors of Colorectal Cancer Cells through the STAT3/MicroRNA-19a/PTEN/PI3K/AKT Axis

Hypoxia is a typical microenvironment feature in almost all solid tumors and is frequently associated with growth of cancers including colorectal cancer (CRC). This study focuses on the influence of hypoxic microenvironment on the activity of CRC cells and the molecules involved. CRC cells were cultured under hypoxic conditions for 48 h, after which the proliferation, migration, invasion, and epithelial-mesenchymal transition activities of cells were increased. MicroRNA- (miR-) 19a was significantly upregulated in cells after hypoxia exposure according to a microarray analysis. STAT3 was confirmed as an upstream regulator of miR-19a which bound to the promoter region of miR-19a at the 96 bp/78 bp sites, and miR-19a bound to the PTEN mRNA to activate the PI3K/AKT signaling pathway. Hypoxia exposure induced STAT3 phosphorylation and PTEN knockdown in CRC cells. Silencing of STAT3 reduced the hypoxia-induced activity of CRC cells, whereas the malignant behaviors of cells were restored after miR-19a upregulation but blocked after PTEN overexpression. Similar results were reproduced in vivo where downregulation of STAT3 or overexpression of PTEN suppressed tumor growth and metastasis in nude mice. This study demonstrated that hypoxia augments activity and malignant behaviors of colorectal cancer cells through the STAT3/miR-19a/PTEN/PI3K/AKT axis.

A Systematic Review of Artificial Intelligence Techniques in Cancer Prediction and Diagnosis

Artificial intelligence has aided in the advancement of healthcare research. The availability of open-source healthcare statistics has prompted researchers to create applications that aid cancer detection and prognosis. Deep learning and machine learning models provide a reliable, rapid, and effective solution to deal with such challenging diseases in these circumstances. PRISMA guidelines had been used to select the articles published on the web of science, EBSCO, and EMBASE between 2009 and 2021. In this study, we performed an efficient search and included the research articles that employed AI-based learning approaches for cancer prediction. A total of 185 papers are considered impactful for cancer prediction using conventional machine and deep learning-based classifications. In addition, the survey also deliberated the work done by the different researchers and highlighted the limitations of the existing literature, and performed the comparison using various parameters such as prediction rate, accuracy, sensitivity, specificity, dice score, detection rate, area undercover, precision, recall, and F1-score. Five investigations have been designed, and solutions to those were explored. Although multiple techniques recommended in the literature have achieved great prediction results, still cancer mortality has not been reduced. Thus, more extensive research to deal with the challenges in the area of cancer prediction is required.

Inhibition of the cell migration, invasion and chemoresistance of colorectal cancer cells through targeting KLF3 by miR-365a-3p

Background: Metastasis and chemoresistance limit treatment efficacy of colorectal cancer (CRC) patients. MicroRNAs (miRNAs) have been believed to be candidate biomarkers for tumor cell proliferation, metastasis and chemoresistance, but the related molecular mechanisms are not clear for prognosis prediction.

Aims: We aimed to investigate the role of miR-365a-3p in metastasis and chemoresistance of CRC.

Methods: The expression levels of miR-365a-3p in clinical CRC tissues were analyzed. The effects of miR-365a-3p expression levels on tumor chemoresistance, invasion and migration were also determined. A dual luciferase reporter gene assay was used to determine the effect of miR-365a-3p on its target gene, Kruppel-like factor 3 (KLF3), and the effect of the miR-365a-3p/KLF3 axis on CRC cell chemoresistance, migration and invasion was further investigated.

Results: In patients with CRC with lymph node or distant organ metastasis or in CRC cell lines, the expression levels of miR-365a-3p were significantly downregulated. In addition, the findings of Transwell assays demonstrated that miR-365a-3p significantly suppressed CRC cell migration and invasion. The dual luciferase reporter gene assay results suggested that miR-365a-3p may play an important role in the regulation of migration, invasion and chemoresistance in CRC cells.

Conclusions: The findings of present study provided evidence to suggest that miR-365a-3p may be a potential tumor suppressor gene in CRC and may inhibit the migration, invasion and chemoresistance of CRC cells. These results suggested that targeting miR-365a-3p/KLF3 axis may represent a potential therapeutic intervention for metastatic disease in patients with CRC.

Identification of serum microRNAs with differential expression between dogs with splenic masses and healthy dogs with histologically normal spleens

OBJECTIVE

To identify differential microRNA (miRNA) expression in dogs with splenic hemangiosarcoma, splenic hematoma, and histologically normal spleens.

ANIMALS

Dogs with splenic hemangiosarcoma (n = 10), splenic hematoma (n = 5), and histologically normal spleens (n = 5).

PROCEDURES

Splenic tissue and serum samples were collected from dogs with splenic masses (ie, hemangiosarcoma or hematoma samples) and healthy control dogs (ie, control samples), and total RNA was extracted. Reverse transcription quantitative real-time PCR was performed with 28 miRNAs associated with hemangiosarcoma, angiosarcoma, or associated genes. Differential expression analysis was performed.

RESULTS

Control tissue and serum samples had similar miRNA expression patterns, and hemangiosarcoma tissue and serum samples did not. Hemangiosarcoma serum samples had higher expression than hemangiosarcoma tissue for 13 miRNAs and lower expression for 1 miRNA. Control tissue and hemangiosarcoma tissue had varying expressions for 12 miRNAs, with 10 more highly expressed in control samples and 2 more highly expressed in hemangiosarcoma samples. Five miRNAs (miR-214-3p, miR-452, miR-494-3p, miR-497-5p, miR-543) had significantly different expression in serum between dogs with splenic masses (ie, hemangiosarcoma or hematoma) and serum of dogs with histologically normal spleens, with higher expression in the serum of dogs with splenic masses for all 5 miRNAs.

CONCLUSIONS AND CLINICAL RELEVANCE

5 circulating miRNAs were identified that distinguished dogs with splenic hemangiosarcoma or hematoma from those with histologically normal spleens. These 5 miRNAs had higher expression in dogs with splenic masses, indicating upregulation of these circulating miRNAs occurs in these splenic disease states. These miRNAs may be useful as a noninvasive screening tool that uses serum to identify dogs with splenic masses.

Integrative Analysis of Identifying Methylation-Driven Genes Signature Predicts Prognosis in Colorectal Carcinoma

Background

Aberrant DNA methylation is a critical regulator of gene expression and plays a crucial role in the occurrence, progression, and prognosis of colorectal cancer (CRC). We aimed to identify methylation-driven genes by integrative epigenetic and transcriptomic analysis to predict the prognosis of CRC patients.

Methods

Methylation-driven genes were selected for CRC using a MethylMix algorithm and LASSO regression screening strategy, and were further used to construct a prognostic risk-assessment model. The Cancer Genome Atlas (TCGA) database was obtained as the training set for both the screening of methylation-driven genes and the effect of genes signature on CRC prognosis. Then, the prognostic genes signature was validated in three independent expression arrays of CRC data from Gene Expression Omnibus (GEO).

Results

We identified 143 methylation-driven genes, of which the combination of BATF, PHYHIPL, RBP1, and PNPLA4 expression levels was screened as a better prognostic model with the best area under the curve (AUC) (AUC = 0.876). Compared with patients in the low-risk group, CRC patients in the high-risk group had significantly poorer overall survival in the training set (HR = 2.184, 95% CI: 1.404–3.396, P < 0.001). Similar results were observed in the validation set. Moreover, VanderWeele’s mediation analysis indicated that the effect of methylation on prognosis was mediated by the levels of their expression (HR_indirect = 1.473, P = 0.001, Proportion mediated, 69.10%).

Conclusions

We identified a four-gene prognostic signature by integrative analysis and developed a risk-assessment model that is significantly associated with patients’ survival. Methylation-driven genes might be a potential prognostic signature for CRC patients.

miR-141 is negatively correlated with TLR4 in neonatal sepsis and regulates LPS-induced inflammatory responses in monocytes

Neonatal sepsis is an inflammatory system syndrome and a main cause of neonatal mortality. However, there is a lack of ideal biomarkers for early neonatal sepsis diagnosis. The aim of this study was to evaluate the clinical significance of miR-141 in sepsis in neonates, and explore the regulatory effects of miR-141 on inflammation in monocytes. This study used qRT-PCR to calculate the expression of miR-141 in the serum of septic neonates. The diagnostic values of procalcitonin (PCT) and serum miR-141 were evaluated by receiver operating characteristic (ROC) curves. The relationship between miR-141 and TLR4 was determined using luciferase reporter assay. An inflammation model was established using monocytes with lipopolysaccharide (LPS) treatment. ELISA assay was used to analyze the levels of pro-inflammatory cytokines. The expression of miR-141 in neonatal sepsis was significantly lower than healthy controls. ROC curves showed that miR-141 had diagnostic accuracy. LPS stimulation in monocytes led to a decrease in the expression of miR-141. A luciferase reporter assay proved that miR-141 targeted TLR4, and a negative correlation of miR-141 with TLR4 was found in septic neonates. ELISA results demonstrated that the overexpression of miR-141 inhibited LPS-induced inflammation in monocytes. In conclusion, serum decreased miR-141 expression served as a candidate diagnostic biomarker of neonatal sepsis. TLR4 is a target gene of miR-141, which may mediate the inhibitory effects of miR-141 overexpression on LPS-induced inflammation in monocytes. Therefore, miR-141 is expected to be a potential diagnostic biomarker and a therapeutic target in neonatal sepsis.

What Is Known about Theragnostic Strategies in Colorectal Cancer

Despite the paradigmatic shift occurred in recent years for defined molecular subtypes in the metastatic setting treatment, colorectal cancer (CRC) still remains an incurable disease in most of the cases. Therefore, there is an urgent need for new tools and biomarkers for both early tumor diagnosis and to improve personalized treatment. Thus, liquid biopsy has emerged as a minimally invasive tool that is capable of detecting genomic alterations from primary or metastatic tumors, allowing the prognostic stratification of patients, the detection of the minimal residual disease after surgical or systemic treatments, the monitoring of therapeutic response, and the development of resistance, establishing an opportunity for early intervention before imaging detection or worsening of clinical symptoms. On the other hand, preclinical and clinical evidence demonstrated the role of gut microbiota dysbiosis in promoting inflammatory responses and cancer initiation. Altered gut microbiota is associated with resistance to chemo drugs and immune checkpoint inhibitors, whereas the use of microbe-targeted therapies including antibiotics, pre-probiotics, and fecal microbiota transplantation can restore response to anticancer drugs, promote immune response, and therefore support current treatment strategies in CRC. In this review, we aim to summarize preclinical and clinical evidence for the utilization of liquid biopsy and gut microbiota in CRC.

Overexpression of rhophilin 2 promotes pancreatic ductal adenocarcinoma

Pancreatic ductal adenocarcinoma (PDAC) is the most common type of pancreatic cancer and is the seventh leading cause of global cancer deaths. In recent years, targeted therapy has been used for pancreatic cancer; however, the drugs available for use in targeted therapy for pancreatic cancer are still very limited. Hence, identification of novel targeted molecules for PDAC is required. Rhophilin 2 (RHPN2) was proven to be a driver gene in glioblastoma. However, the function of RHPN2 in PDAC remains unknown. In the present study, the function of RHPN2 was investigated. The RHPN2 levels were overexpressed by pcDNA3.1-RHPN2 and downregulated by si-RHPN2. Cell proliferation was assessed using the MTT assay and apoptosis was assessed using flow cytometry. The results revealed that high RHPN2 levels in PDAC tissue were correlated with a low overall survival rate of patients with PDAC. Inhibition of RHPN2 reduced SW1990 and PANC1 proliferation and increased the rate of apoptosis. Network analysis demonstrated that centrosomal protein 78 expression was negatively correlated with RHPN2 expression. In conclusion, the present study demonstrated that RHPN2 may promote PDAC making it a potential candidate for targeted therapy.

Mechanisms of Core Chinese Herbs against Colorectal Cancer: A Study Based on Data Mining and Network Pharmacology

Colorectal cancer (CRC) is now the second most deadly cancer globally. Chinese herbal medicine (CHM) plays an indispensable role in CRC treatment in China. However, the core herbs (the CHs) in the treatment of CRC and their underlying therapeutic mechanisms remain unclear. This study aims to uncovering the CHs and their mechanisms of action of CRC treatment, applying data mining and network pharmacology approach. First, CHM prescriptions treating CRC were collected from clinical studies from the Chinese National Knowledge Infrastructure (CNKI) and MEDLINE databases, and the CHs were identified through data mining. Then, the bioactive compounds and the corresponding putative targets of the CHs were obtained from three traditional Chinese medicine (TCM) databases. CRC related targets were acquired from three disease databases; the overlapping targets between the CHs and CRC were identified as the therapeutic targets. Subsequently, functional enrichment analysis was performed to elucidate the mechanisms of the CHs on CRC. Moreover, networks were constructed to screen the major bioactive compounds and therapeutic targets. Finally, prognostic values of the major target genes were evaluated by survival analysis, and molecular docking simulation was performed to assess the binding affinity of key targets and major bioactive compounds. It came out that 10 the CHs from 113 prescriptions and 190 bioactive compounds with 118 therapeutic targets were identified. The therapeutic targets were mainly enriched in the biological progress of transcription, apoptosis, and response to cytokine. Various cancer-associated signaling pathways, including microRNAs, TNF, apoptosis, PI3K-Akt, and p53, were involved. Furthermore, 15 major bioactive compounds and five key target genes (VEGFA, CASP3, MYC, CYP1Y1, and NFKB1) with prognostic significance were identified. Additionally, most major bioactive compounds might bind firmly to the key target proteins. This study provided an overview of the anti-CRC mechanisms of the CHs, which might refer to the regulation of apoptosis, transcription, and inflammation.

Fuzheng Huayu recipe, a traditional Chinese compound herbal medicine, attenuates renal interstitial fibrosis via targeting the miR-21/PTEN/AKT axis

OBJECTIVE

MicroRNAs (miRNAs) may be viable targets for treating renal interstitial fibrosis (RIF). Fuzheng Huayu recipe (FZHY), a traditional Chinese compound herbal medicine, is often used in China to treat fibrosis. This study sought to assess the mechanisms through which FZHY influences miRNAs to treat RIF.

METHODS

RIF was induced in rats by mercury chloride and treated with FZHY. Hydroxyproline content, Masson's staining and type I collagen expression were used to evaluate renal collagen deposition. Renal miRNA profiles were evaluated using a miRNA microarray. Those miRNAs that were differentially expressed following FZHY treatment were identified and subjected to bioinformatic analyses. The miR-21 target gene phosphatase and tensin homolog (PTEN) expression and AKT phosphorylation in kidney tissues were assessed via Western blotting. In addition, HK-2 human proximal tubule epithelial cells were treated using angiotensin II (Ang-II) to induce epithelial-to-mesenchymal transition (EMT), followed by FZHY exposure. miR-21 and PTEN expressions were evaluated via quantitative reverse transcription-polymerase chain reaction (qRT-PCR), while E-cadherin and α-smooth muscle actin (α-SMA) expressions were assessed by immunofluorescent staining and qRT-PCR. Western blotting was used to assess PTEN and AKT phosphorylation.

RESULTS

FZHY significantly decreased kidney collagen deposition, hydroxyproline content and type I collagen level. The miRNA microarray identified 20 miRNAs that were differentially expressed in response to FZHY treatment. Subsequent bioinformatic analyses found that miR-21 was the key fibrosis-related miRNA regulated by FZHY. FZHY also decreased PTEN expression and AKT phosphorylation in fibrotic kidneys. Results from in vitro tests also suggested that FZHY promoted E-cadherin upregulation and inhibited α-SMA expression in Ang-II-treated HK-2 cells, effectively reversing Ang-II-mediated EMT. We also determined that FZHY reduced miR-21 expression, increased PTEN expression and decreased AKT phosphorylation in these cells.

CONCLUSION

miR-21 is the key fibrosis-related miRNA regulated by FZHY. The ability of FZHY to modulate miR-21/PTEN/AKT signaling may be a viable approach for treating RIF.