Knocking Out SST Gene of BGC823 Gastric Cancer Cell by CRISPR/Cas9 Enhances Migration, Invasion and Expression of SEMA5A and KLF2

Octreotide attenuates intestinal barrier damage by maintaining basal autophagy in Caco2 cells

The intestinal mucosal barrier is of great importance for maintaining the stability of the internal environment, which is closely related to the occurrence and development of intestinal inflammation. Octreotide (OCT) has potential applicable clinical value for treating intestinal injury according to previous studies, but the underlying molecular mechanisms have remained elusive. This article is based on a cell model of inflammation induced by lipopolysaccharide (LPS), aiming to explore the effects of OCT in protecting intestinal mucosal barrier function. A Cell Counting Kit‑8 assay was used to determine cell viability and evaluate the effectiveness of OCT. Gene silencing technology was used to reveal the mediated effect of somatostatin receptor 2 (SSTR2). The changes in intestinal permeability were detected through trans‑epithelial electrical resistance and fluorescein isothiocyanate‑dextran 4 experiments, and the alterations in tight junction proteins were detected using immunoblotting and reverse transcription fluorescence‑quantitative PCR technology. Autophagosomes were observed by electron microscopy and the dynamic changes of the autophagy process were characterized by light chain (LC)3‑II/LC3‑I conversion and autophagic flow. The results indicated that SSTR2‑dependent OCT can prevent the decrease in cell activity. After LPS treatment, the permeability of monolayer cells decreased and intercellular tight junctions were disrupted, resulting in a decrease in tight junction protein zona occludens 1 in cells. The level of autophagy‑related protein LC3 was altered to varying degrees at different times. These abnormal changes gradually returned to normal levels after the combined application of LPS and SSTR2‑dependent OCT, confirming the role of OCT in protecting intestinal barrier function. These experimental results suggest that OCT maintains basal autophagy and cell activity mediated by SSTR2 in intestinal epithelial cells, thereby preventing the intestinal barrier dysfunction in inflammation injury.

A three-gene random forest model for diagnosing idiopathic pulmonary fibrosis based on circadian rhythm-related genes in lung tissue

BACKGROUND

The disorder of circadian rhythm could be a key factor mediating fibrotic lung disease Therefore, our study aims to determine the diagnostic value of circadian rhythm-related genes (CRRGs) in IPF.

METHODS

We retrieved the data on CRRGs from previous studies and the GSE150910 dataset. The participants from the GSE150910 dataset were divided into training and internal validation sets. Next, we used several various bioinformatics methods and machine learning algorithms to screen genes. Next, we identified SEMA5A, COL7A1, and TUBB3, which were included in the random forest (RF) diagnostic model. Finally, external validation was conducted on data retrieved from the GSE184316 datasets.

RESULTS

The results revealed that the RF diagnostic model could diagnose patients with IPF in the internal validation set with the area under the ROC curve (AUC) value of 0.905 and in the external validation with the AUC value of 0.767. Furthermore, real-time quantitative PCR and western blotting results revealed a significant decrease in SEMA5A (p < 0.05) expression level and an increase in COL7A1 and TUBB3 expression levels in TGF-β1-treated normal human lung fibroblasts.

CONCLUSION

We constructed an RF diagnostic model based on SEMA5A, COL7A1, and TUBB3 expression in lung tissue for diagnosing patients with IPF.

Identification of GNG7 as a novel biomarker and potential therapeutic target for gastric cancer via bioinformatic analysis and in vitro experiments

Gastric cancer (GC) is one of the most common malignancies with unfavorable prognoses. The present study aimed to identify novel biomarkers or potential therapeutic targets in GC via bioinformatic analysis and in vitro experiments. The Gene Expression Omnibus and The Cancer Genome Atlas databases were used to screen the differentially expressed genes (DEGs). After protein-protein interaction network construction, both module and prognostic analyses were performed to identify prognosis-related genes in GC. The expression patterns and functions of G protein γ subunit 7 (GNG7) in GC were then visualized in multiple databases and further verified using in vitro experiments. A total of 897 overlapping DEGs were detected and 20 hub genes were identified via systematic analysis. After accessing the prognostic value of the hub genes using the online server Kaplan-Meier plotter, a six-gene prognostic signature was identified, which was also significantly correlated with the process of immune infiltration in GC. The results of open-access database analyses suggested that GNG7 is downregulated in GC; this downregulation was associated with tumor progression. Furthermore, the functional enrichment analysis unveiled that the GNG7-coexpressed genes or gene sets were closely correlated with the proliferation and cell cycle processes of GC cells. Finally, in vitro experiments further confirmed that GNG7 overexpression inhibited GC cell proliferation, colony formation, and cell cycle progression and induced apoptosis. As a tumor suppressor gene, GNG7 suppressed the growth of GC cells via cell cycle blockade and apoptosis induction and thus may be used as a potential biomarker and therapeutic target for GC.

Tumor-derived extracellular vesicles confer 5-fluorouracil resistance in esophageal cancer via long noncoding RNA AC116025.2 delivery

5-Fluorouracil (5-FU) resistance is one of the main causes for treatment failure in esophageal cancer (EC). Here, we intended to elucidate the mechanism of tumor-derived extracellular vesicles (TEVs)-encapsulated long noncoding RNAs (lncRNAs) AC116025.2 in 5-FU resistance in EC. EVs were isolated from the serum samples of EC patients and HEEC, TE-1, and TE-1/5-FU cells, followed by RT-qPCR detection of AC116025.2 expression in EVs. The relationship among AC116025.2, microRNA (miR)-4496, and SEMA5A was evaluated. Next, EC cells were cocultured with EVs, followed by lentivirus transduction and plasmid transfection for studying the role of TEVs-AC116025.2 in EC cells in relation to miR-4496 and SEMA5A. Tumor formation in nude mice was applied for in vivo confirmation. Elevated AC116025.2 expression was seen in the EVs from the serum of 5-FU insensitive patients and from 5-FU-resistant EC cells. Mechanistically, AC116025.2 bound to miR-4496 that inversely targeted SEMA5A in EC cells. EVs-oe-AC116025.2 augmented EC cell viability, colony formation, and 5-FU resistance, but diminished their apoptosis through miR-4496-mediated SEMA5A. Furthermore, EVs-oe-AC116025.2 augmented tumor formation and 5-FU resistance of EC cells in vivo. Conclusively, our data offered evidence of the promoting mechanism of TEVs in the 5-FU resistance of EC by delivering AC116025.2.

CRISPR/Cas9 Genome-Editing Technology and Potential Clinical Application in Gastric Cancer

Gastric cancer is the subject of clinical and basic studies due to its high incidence and mortality rates worldwide. Due to the diagnosis occurring in advanced stages and the classic treatment methodologies such as gastrectomy and chemotherapy, they are extremely aggressive and limit the quality of life of these patients. CRISPR/Cas9 is a tool that allows gene editing and has been used to explore the functions of genes related to gastric cancer, in addition to being used in the treatment of this neoplasm, greatly increasing our understanding of cancer genomics. In this mini-review, we seek the current status of the CRISPR/Cas9 gene-editing technology in gastric cancer research and clinical research.

Comprehensive Assessment of Somatostatin Receptors in Various Neoplasms: A Systematic Review

Somatostatin receptors (SSTR) are expressed in various neoplasms and can be targeted for both diagnostics as well as therapeutics. This systematic review aims to compile and discuss the prevalence of somatostatin receptor expression in various neoplasms. We performed a literature search from Google Scholar and PubMed using relevant keywords to look for all publicly available data regarding SSTR expression in various cancers. Both histopathological and radiographical studies were included for SSTR assessment. We found that many cancers express SSTR with varying prevalence. SSTR is now a well-established theranostics biomarker. We now have highly sensitive and specific diagnostic modalities like gallium 68 DOTATATE and copper 64 DOTATATE scans to screen for SSTR-2 and then target it therapeutically with lutetium 177 DOTATATE. A thorough understanding of SSTR expression in other tumors will open the channels for exploring potential SSTR targeting.

CRISPR/Cas9: A revolutionary genome editing tool for human cancers treatment

Cancer is a genetic disease stemming from genetic and epigenetic mutations and is the second most common cause of death across the globe. Clustered regularly interspaced short palindromic repeats (CRISPR) is an emerging gene-editing tool, acting as a defense system in bacteria and archaea. CRISPR/Cas9 technology holds immense potential in cancer diagnosis and treatment and has been utilized to develop cancer disease models such as medulloblastoma and glioblastoma mice models. In diagnostics, CRISPR can be used to quickly and efficiently detect genes involved in various cancer development, proliferation, metastasis, and drug resistance. CRISPR/Cas9 mediated cancer immunotherapy is a well-known treatment option after surgery, chemotherapy, and radiation therapy. It has marked a turning point in cancer treatment. However, despite its advantages and tremendous potential, there are many challenges such as off-target effects, editing efficiency of CRISPR/Cas9, efficient delivery of CRISPR/Cas9 components into the target cells and tissues, and low efficiency of HDR, which are some of the main issues and need further research and development for completely clinical application of this novel gene editing tool. Here, we present a CRISPR/Cas9 mediated cancer treatment method, its role and applications in various cancer treatments, its challenges, and possible solution to counter these challenges.

Immune and Stromal Related Genes in Colon Cancer: Analysis of Tumor Microenvironment Based on The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) Databases

BACKGROUND

The incidence of colon cancer is among the top three in the world. The tumor microenvironment plays an important role in the occurrence and development of colon cancer. Stromal cells and immune cells are the main components of the tumor microenvironment.

METHODS

Our study detected genes which affected the infiltration of stromal, immune cells and the way they affected the prognosis of colon cancer patients.

RESULTS

We found that the colon's immune system had a special way to affect the tumor microenvironment. Moderate infiltration of stromal and immune cells were proved to be important protective factors for colon cancer patients, which has not been found in other tumors. C3, C5, CXCL12, GNAI1, LPAR1, PENK, PYY, SAA1 and SST were the differential expression hub genes of moderate stromal and immune score group. They had a more significant correlation with tumor purity and infiltration of B cells, CD8⁺ T cells, CD4⁺ T cells, macrophage, neutrophil, democratic cells. The proteins encoded by C3, C5, CXCL12, GNAI1, PENK, PYY, SST were detected in colon cancer cells.

CONCLUSION

These genes had the potential to become markers to predict the prognosis of patients with colon cancer.

CD105 expression is associated with invasive capacity in ovarian cancer and promotes invasiveness by inhibiting NDRG1 and regulating the epithelial-mesenchymal transition

This study investigates the association of CD105 (endoglin) with the invasiveness of paclitaxel-resistant ovarian cancer (OC) cells and explores the potential mechanism. A paclitaxel-resistant OC cell line OC3/TAX300, which expresses the stem cell marker CD105 and has a high invasive potential, was established in our previous study. After CD105 knockdown using CD105 siRNA, the invasiveness of the OC cells was decreased, and the chemo-resistance was reversed, but the CD105 overexpression was related to the poor survival of the primary OC patients. The differentially expressed genes were investigated in the OC cells after the CD105 knockdown. The results showed that, in the CD105-siRNA transfected cells, the expressions of some genes (such as KIAA0125, SSTR5-AS1, CDH18, MIAT, NDRG1, E-cadherin, DUSP1, MAL, MYC, and JAK3) were significantly upregulated, but the expressions of other genes (such as PRKAR2B, KLK10, DDX17, and lncRNA SNHG7) were markedly downregulated. Several genes, such as NDRG1 and E-cadherin, are known to be related to cancer metastasis and the epithelial-mesenchymal transition (EMT). A KEGG analysis found that 264 signaling pathways changed after the CD105 knockdown, of which 27 signaling pathways showed significant enrichment. Our results show that CD105 is related to the metastasis of OC and may promote the EMT of OC by inhibiting NDRG1 and E-cadherin. MYC, JAK3, and IKBKB mediate the CD105-induced metastasis of OC via the MAPK/PI3K/AKT and JAK/STAT signaling pathways in the OC cells. Therefore, inhibiting the CD105 expression may be useful for treating OC.

Nanotechnology-based delivery of CRISPR/Cas9 for cancer treatment

CRISPR/Cas9 (Clustered Regularly Interspaced Short Palindromic Repeats-associated protein 9) is a potent technology for gene-editing. Owing to its high specificity and efficiency, CRISPR/Cas9 is extensity used for human diseases treatment, especially for cancer, which involves multiple genetic alterations. Different concepts of cancer treatment by CRISPR/Cas9 are established. However, significant challenges remain for its clinical applications. The greatest challenge for CRISPR/Cas9 therapy is how to safely and efficiently deliver it to target sites in vivo. Nanotechnology has greatly contributed to cancer drug delivery. Here, we present the action mechanisms of CRISPR/Cas9, its application in cancer therapy and especially focus on the nanotechnology-based delivery of CRISPR/Cas9 for cancer gene editing and immunotherapy to pave the way for its clinical translation. We detail the difficult barriers for CRISIR/Cas9 delivery in vivo and discuss the relative solutions for encapsulation, target delivery, controlled release, cellular internalization, and endosomal escape.

Epigenetic regulation of somatostatin and somatostatin receptors in neuroendocrine tumors and other types of cancer

Both somatostatin (SST) and somatostatin receptors (SSTRs) are proteins with important functions in both physiological tissue and in tumors, particularly in neuroendocrine tumors (NETs). NETs are frequently characterized by high SSTRs expression levels. SST analogues (SSAs) that bind and activate SSTR have anti-proliferative and anti-secretory activity, thereby reducing both the growth as well as the hormonal symptoms of NETs. Moreover, the high expression levels of SSTR type-2 (SSTR2) in NETs is a powerful target for therapy with radiolabeled SSAs. Due to the important role of both SST and SSTRs, it is of great importance to elucidate the mechanisms involved in regulating their expression in NETs, as well as in other types of tumors. The field of epigenetics recently gained interest in NET research, highlighting the importance of this process in regulating the expression of gene and protein expression. In this review we will discuss the role of the epigenetic machinery in controlling the expression of both SSTRs and the neuropeptide SST. Particular attention will be given to the epigenetic regulation of these proteins in NETs, whereas the involvement of the epigenetic machinery in other types of cancer will be discussed as well. In addition, we will discuss the possibility to target enzymes involved in the epigenetic machinery to modify the expression of the SST-system, thereby possibly improving therapeutic options.

Construction of circRNA-miRNA-mRNA network in the pathogenesis of recurrent implantation failure using integrated bioinformatics study

This research attempted to elucidate the molecular components are involved in the pathogenesis of recurrent implantation failure (RIF). We initially identified that 386 mRNAs, 144 miRNAs and 2548 circRNAs were differentially expressed (DE) in RIF and then investigated the genetic cause of the observed abnormal expression by constructing a circRNA‐miRNA‐mRNA network considering the competing endogenous RNA theory. We further analysed the upstream transcription factors and related kinases of DEmRNAs (DEMs) and demonstrated that SUZ12, AR, TP63, NANOG, and TCF3 were the top five TFs binding to these DEMs. Besides, protein‐protein interaction analysis disclosed that ACTB, CXCL10, PTGS2, CXCL12, GNG4, AGT, CXCL11, SST, PENK, and FOXM1 were the top 10 hub genes in the acquired network. Finally, we performed the functional enrichment analysis and found that arrhythmogenic right ventricular cardiomyopathy (ARVC), hypertrophic cardiomyopathy (HCM), pathways in cancer, TNF signalling pathway and steroid hormone biosynthesis were the potentially disrupted pathways in RIF patients. Optimistically, our findings may deepen our apprehensions about the underlying molecular and biological causes of RIF and provide vital clues for future laboratory and clinical experiments that will ultimately bring a better outcome for patients with RIF.

The role of SOX family transcription factors in gastric cancer

Gastric cancer (GC) is a leading cause of death worldwide. GC is the third-most common cause of cancer-related death after lung and colorectal cancer. It is also the fifth-most commonly diagnosed cancer. Accumulating evidence has revealed the role of signaling networks in GC progression. Identification of these molecular pathways can provide new insight into therapeutic approaches for GC. Several molecular factors involved in GC can play both onco-suppressor and oncogene roles. Sex-determining region Y (Sry)-box-containing (SOX) family members are transcription factors with a well-known role in cancer. SOX proteins can bind to DNA to regulate cellular pathways via a highly conserved domain known as high mobility group (HMG). In the present review, the roles of SOX proteins in the progression and/or inhibition of GC are discussed. The dual role of SOX proteins as tumor-promoting and tumor-suppressing factors is highlighted. SOX members can affect upstream mediators (microRNAs, long non-coding RNAs and NF-κB) and down-stream mediators (FAK, HIF-1α, CDX2 and PTEN) in GC. The possible role of anti-tumor compounds to target SOX pathway members in GC therapy is described. Moreover, SOX proteins may be used as diagnostic or prognostic biomarkers in GC.