CRISPR/Cas9-mediated knockout of the PDEF gene inhibits migration and invasion of human gastric cancer AGS cells

Transcription Factors in Prostate Cancer: Insights for Disease Development and Diagnostic and Therapeutic Approaches

Transcription factors (TFs) are proteins essential for the regulation of gene expression, and they regulate the genes involved in different cellular processes, such as proliferation, differentiation, survival, and apoptosis. Although their expression is essential in normal physiological conditions, abnormal regulation of TFs plays critical role in several diseases, including cancer. In prostate cancer, the most common malignancy in men, TFs are known to play crucial roles in the initiation, progression, and resistance to therapy of the disease. Understanding the interplay between these TFs and their downstream targets provides insights into the molecular basis of prostate cancer pathogenesis. In this review, we discuss the involvement of key TFs, including the E26 Transformation-Specific (ETS) Family (ERG and SPDEF), NF-κB, Activating Protein-1 (AP-1), MYC, and androgen receptor (AR), in prostate cancer while focusing on the molecular mechanisms involved in prostate cancer development. We also discuss emerging diagnostic strategies, early detection, and risk stratification using TFs. Furthermore, we explore the development of therapeutic interventions targeting TF pathways, including the use of small molecule inhibitors, gene therapies, and immunotherapies, aimed at disrupting oncogenic TF signaling and improving patient outcomes. Understanding the complex regulation of TFs in prostate cancer provides valuable insights into disease biology, which ultimately may lead to advancing precision approaches for patients.

Quercetin promotes ATG5-mediating autophagy-dependent ferroptosis in gastric cancer

Quercetin has been documented to possess a multitude of pharmacological effects, encompassing antioxidant, antiviral, antimicrobial, and anti-inflammatory properties. Nevertheless, the exact molecular mechanisms responsible for the anti-tumor properties of quercetin remain to be fully explicated. To this end, quercetin was administered to gastric cancer cells (in vitro) AGS and MKN45, as well as BALB/c mice (in vivo). The proliferation ability of cells was evaluated using cholecystokinin octapeptide (CCK-8) and colony formation assays. The evaluation of ferroptosis involved the measurement of iron, malondialdehyde (MDA), and lipid reactive oxygen species. Autophagy and apoptosis were evaluated using immunofluorescence staining, western blotting, and flow cytometry analysis. Our findings indicate that quercetin significantly inhibited cell viability and tumor volume compared to the control group. Additionally, quercetin was found to decrease glutathione (GSH), malondialdehyde, and reactive oxygen species (ROS) levels while suppressing beclin1 and LC3B levels in cancer cells. Remarkably, the utilization of siATG5 was found to reverse all the aforementioned effects of quercetin. Ultimately, the effects of quercetin on gastric cancer were validated. In summary, our findings provide evidence that quercetin facilitates autophagy-mediated ferroptosis in gastric cancer.

New insight into the mechanisms of Ginkgo biloba leaves in the treatment of cancer

BACKGROUND

Ginkgo biloba leaves (GBLs), as an herbal dietary supplement and a traditional Chinese medicine, have been used in treating diseases for hundred years. Recently, increasing evidence reveals that the extracts and active ingredients of GBLs have anti-cancer (chemo-preventive) properties. However, the molecular mechanism of GBLs in anti-cancer has not been comprehensively summarized.

PURPOSE

To systematically summarize the literatures for identifying the molecular mechanism of GBLs in cellular, animal models and clinical trials of cancers, as well as for critically evaluating the current evidence of efficacy and safety of GBLs for cancers.

METHODS

Employing the search terms "Ginkgo biloba" and "cancer" till July 25, 2023, a comprehensive search was carried out in four electronic databases including Scopus, PubMed, Google Scholar and Web of Science. The articles not contained in the databases are performed by manual searches and all the literatures on anti-cancer research and mechanism of action of GBLs was extracted and summarized. The quality of methodology was assessed independently through PRISMA 2020.

RESULTS

Among 84 records found in the database, 28 were systematic reviews related to GBLs, while the remaining 56 records were related to the anticancer effects of GBLs, which include studies on the anticancer activities and mechanisms of extracts or its components in GBLs at cellular, animal, and clinical levels. During these studies, the top six cancer types associated with GBLs are lung cancer, hepatocellular carcinoma, gastric cancer, breast cancer, colorectal cancer, and cervical cancer. Further analysis reveals that GBLs primarily exert their anticancer effects by stimulating cancer cell apoptosis, inhibiting cell proliferation, invasion and migration of cancers, exhibiting anti-inflammatory and antioxidant properties, and modulating signaling pathways. Besides, the pharmacology, toxicology, and clinical research on the anti-tumor activity of GBLs have also been discussed.

CONCLUSIONS

This is the first paper to thoroughly investigate the pharmacology effect, toxicology, and the mechanisms of action of GBLs for anti-cancer properties. All the findings will reinforce the need to explore the new usage of GBLs in cancers and offer comprehensive reference data and recommendations for future research on this herbal medicine.

CRISPR/Cas9 systems: Delivery technologies and biomedical applications

The emergence of the clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated protein 9 (Cas9) genome-editing system has brought about a significant revolution in the realm of managing human diseases, establishing animal models, and so on. To fully harness the potential of this potent gene-editing tool, ensuring efficient and secure delivery to the target site is paramount. Consequently, developing effective delivery methods for the CRISPR/Cas9 system has become a critical area of research. In this review, we present a comprehensive outline of delivery strategies and discuss their biomedical applications in the CRISPR/Cas9 system. We also provide an in-depth analysis of physical, viral vector, and non-viral vector delivery strategies, including plasmid-, mRNA- and protein-based approach. In addition, we illustrate the biomedical applications of the CRISPR/Cas9 system. This review highlights the key factors affecting the delivery process and the current challenges facing the CRISPR/Cas9 system, while also delineating future directions and prospects that could inspire innovative delivery strategies. This review aims to provide new insights and ideas for advancing CRISPR/Cas9-based delivery strategies and to facilitate breakthroughs in biomedical research and therapeutic applications.

Applications of CRISPR-Cas9 for advancing precision medicine in oncology: from target discovery to disease modeling

The clustered regularly interspaced short palindromic repeats (CRISPR) and CRISPR-associated protein 9 (Cas9) (CRISPR/Cas9) system is a powerful tool that enables precise and efficient gene manipulation. In a relatively short time, CRISPR has risen to become the preferred gene-editing system due to its high efficiency, simplicity, and programmability at low costs. Furthermore, in the recent years, the CRISPR toolkit has been rapidly expanding, and the emerging advancements have shown tremendous potential in uncovering molecular mechanisms and new therapeutic strategies for human diseases. In this review, we provide our perspectives on the recent advancements in CRISPR technology and its impact on precision medicine, ranging from target identification, disease modeling, and diagnostics. We also discuss the impact of novel approaches such as epigenome, base, and prime editing on preclinical cancer drug discovery.

Solanine Represses Gastric Cancer Growth by Mediating Autophagy Through AAMDC/MYC/ATF4/Sesn2 Signaling Pathway

Purpose

Solanine is the main component of the plant Solanum, which has been shown to provide growth-limiting activities in a variety of human cancers. However, little is known about its function in gastric cancer (GC).

Methods

We investigated the effect of solanine on GC in vivo and in vitro. The inhibition rate of solanine on the tumor was observed by constructing a subcutaneous tumor in nude mice. Morphological changes were analyzed with H&E staining. The expression of ATF4 was detected by IF analysis. MTT assays, EdU staining, and colony formation assays were used to detect the inhibition rate of solanine on GC cells. Matrigel transwells were used to detect the invasion of GC cells. Cell migration was measured using the wound healing assay. The flow cytometric analysis was used to monitor changes in the cell cycle and cell apoptosis. Western blotting was used to detect major proteins in cells and tumors.

Results

Solanine suppressed gastric tumorigenesis. Solanine also inhibited the proliferation, invasion and mitigation of GC cells, and induced cell cycle arrest and apoptosis in vitro. Moreover, the growth-limiting activities of solanine in gastric cancer were related to the suppression of the AAMDC/MYC/ATF4/Sesn2 pathway-mediated autophagy. Overexpression of AAMDC reversed the inhibitory effect of solanine on autophagy and gastric cancer.

Conclusion

In summary, our findings indicate that solanine confers growth-limiting activities by deactivating the AAMDC-regulated autophagy in gastric cancer.

Recent Advances and Therapeutic Strategies Using CRISPR Genome Editing Technique for the Treatment of Cancer

CRISPR genome editing technique has the potential to target cancer cells in a precise manner. The latest advancements have helped to address one of the prominent concerns about this strategy which is the off-target integrations observed with dsDNA and have resulted in more studies being carried out for potentially safer and more targeted gene therapy, so as to make it available for the clinical trials in order to effectively treat cancer. CRISPR screens offer great potential for the high throughput investigation of the gene functionality in various tumors. It extends its capability to identify the tumor growth essential genes, therapeutic resistant genes, and immunotherapeutic responses. CRISPR screens are mostly performed in in vitro models, but latest advancements focus on developing in vivo models to view cancer progression in animal models. It also allows the detection of factors responsible for tumorigenesis. In CRISPR screens key parameters are optimized in order to meet proficient gene targeting efficiencies. It also detects various molecular effectors required for gene regulation in different cancers, essential pathways which modulate cytotoxicity to immunotherapy in cancer cells, important genes which contribute to cancer cell survival in hypoxic states and modulate cancer long non-coding RNAs. The current review focuses on the recent developments in the therapeutic application of CRISPR technology for cancer therapy. Furthermore, the associated challenges and safety concerns along with the various strategies that can be implemented to overcome these drawbacks has been discussed.

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.

Characterizing genes associated with cancer using the CRISPR/Cas9 system: A systematic review of genes and methodological approaches

The CRISPR/Cas9 system enables a versatile set of genomes editing and genetic-based disease modeling tools due to its high specificity, efficiency, and accessible design and implementation. In cancer, the CRISPR/Cas9 system has been used to characterize genes and explore different mechanisms implicated in tumorigenesis. Different experimental strategies have been proposed in recent years, showing dependency on various intrinsic factors such as cancer type, gene function, mutation type, and technical approaches such as cell line, Cas9 expression, and transfection options. However, the successful methodological approaches, genes, and other experimental factors have not been analyzed. We, therefore, initially considered more than 1,300 research articles related to CRISPR/Cas9 in cancer to finally examine more than 400 full-text research publications. We summarize findings regarding target genes, RNA guide designs, cloning, Cas9 delivery systems, cell enrichment, and experimental validations. This analysis provides valuable information and guidance for future cancer gene validation experiments.

CRISPR/Cas9 application in cancer therapy: a pioneering genome editing tool

The progress of genetic engineering in the 1970s brought about a paradigm shift in genome editing technology. The clustered regularly interspaced short palindromic repeats/CRISPR associated protein 9 (CRISPR/Cas9) system is a flexible means to target and modify particular DNA sequences in the genome. Several applications of CRISPR/Cas9 are presently being studied in cancer biology and oncology to provide vigorous site-specific gene editing to enhance its biological and clinical uses. CRISPR's flexibility and ease of use have enabled the prompt achievement of almost any preferred alteration with greater efficiency and lower cost than preceding modalities. Also, CRISPR/Cas9 technology has recently been applied to improve the safety and efficacy of chimeric antigen receptor (CAR)-T cell therapies and defeat tumor cell resistance to conventional treatments such as chemotherapy and radiotherapy. The current review summarizes the application of CRISPR/Cas9 in cancer therapy. We also discuss the present obstacles and contemplate future possibilities in this context.

Transcription factor Fli-1 as a new target for antitumor drug development

The transcription factor Friend leukemia virus integration 1 (Fli-1) belonging to the E26 Transformation-Specific (ETS) transcription factor family is not only expressed in normal cells such as hematopoietic stem cells and vascular endothelial cells, but also abnormally expressed in various malignant tumors including Ewing sarcoma, Merkel cell sarcoma, small cell lung carcinoma, benign or malignant hemangioma, squamous cell carcinoma, adenocarcinoma, bladder cancer, leukemia, and lymphoma. Fli-1 binds to the promoter or enhancer of the target genes and participates in a variety of physiological and pathological processes of tumor cells, including cell growth, proliferation, differentiation, and apoptosis. The expression of Fli-1 gene is related to the specific biological functions and characteristics of the tissue in which it is located. In tumor research, Fli-1 gene is used as a specific marker for the occurrence, metastasis, efficacy, and prognosis of tumors, thus, a potential new target for tumor diagnosis and treatment. These studies indicated that Fli-1 may be a specific candidate for antitumor drug development. Recent studies identified small molecules regulating Fli-1 thanks to our screened strategy of natural products and their derivatives. Therefore, in this review, the advanced research on Fli-1 as a target for antitumor drug development is analyzed in different cancers. The inhibitors and agonists of Fli-1 that regulate its expression are introduced and their clinical applications in the treatment of cancer, thus providing new therapeutic strategies.

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.

CRISPR/Cas9 in Gastrointestinal Malignancies

Gastrointestinal (GI) cancers such as colorectal cancer (CRC), gastric cancer (GC), esophageal cancer (EG), pancreatic duct adenocarcinoma (PDAC) or hepatocellular cancer (HCC) belong to the most commonly diagnosed types of cancer and are among the most frequent causes of cancer related death worldwide. Most types of GI cancer develop in a stepwise fashion with the occurrence of various driver mutations during tumor progression. Understanding the precise function of mutations driving GI cancer development has been regarded as a prerequisite for an improved clinical management of GI malignancies. During recent years, CRISPR/Cas9 has developed into a powerful tool for genome editing in cancer research by knocking in and knocking out even multiple genes at the same time. Within this review, we discuss recent applications for CRISPR/Cas9-based genome editing in GI cancer research including CRC, GC, EG, PDAC and HCC. These applications include functional studies of candidate genes in cancer cell lines or organoids in vitro as well as in murine cancer models in vivo, library screening for the identification of previously unknown driver mutations and even gene therapy of GI cancers.

SPDEF suppresses head and neck squamous cell carcinoma progression by transcriptionally activating NR4A1

SAM pointed domain containing E26 transformation-specific transcription factor (SPDEF) plays dual roles in the initiation and development of human malignancies. However, the biological role of SPDEF in head and neck squamous cell carcinoma (HNSCC) remains unclear. In this study, the expression level of SPDEF and its correlation with the clinical parameters of patients with HNSCC were determined using TCGA-HNSC, GSE65858, and our own clinical cohorts. CCK8, colony formation, cell cycle analysis, and a xenograft tumor growth model were used to determine the molecular functions of SPDEF in HNSCC. ChIP-qPCR, dual luciferase reporter assay, and rescue experiments were conducted to explore the potential molecular mechanism of SPDEF in HNSCC. Compared with normal epithelial tissues, SPDEF was significantly downregulated in HNSCC tissues. Patients with HNSCC with low SPDEF mRNA levels exhibited poor clinical outcomes. Restoring SPDEF inhibited HNSCC cell viability and colony formation and induced G0/G1 cell cycle arrest, while silencing SPDEF promoted cell proliferation in vitro. The xenograft tumor growth model showed that tumors with SPDEF overexpression had slower growth rates, smaller volumes, and lower weights. SPDEF could directly bind to the promoter region of NR4A1 and promoted its transcription, inducing the suppression of AKT, MAPK, and NF-κB signaling pathways. Moreover, silencing NR4A1 blocked the suppressive effect of SPDEF in HNSCC cells. Here, we demonstrate that SPDEF acts as a tumor suppressor by transcriptionally activating NR4A1 in HNSCC. Our findings provide novel insights into the molecular mechanism of SPDEF in tumorigenesis and a novel potential therapeutic target for HNSCC.

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.

Evaluation of CRISPR/Cas9 System Effects on Knocking Out NEAT1 Gene in AGS Gastric Cancer Cell Line with Therapeutic Perspective

AIM

Gastric cancer (GC) is one of the most common malignant tumors globally, with an increasing incidence rate. Nuclear paraspeckle assembly transcript 1 (NEAT1) is a long non-coding RNA (lncRNAs) responsible for regulating cell cycle progression, apoptosis, cell growth, proliferation, and migration in various cells. The present survey was performed to assess the effects of NEAT1 gene knocking out by CRISPR/Cas9 system in human gastric cancer cells.

METHODS

The CRISPR/Cas9 genome editing technique was used to knockout NEAT1 in AGS cells as a gastric cancer model. After the design and construction of the vector, transfection was performed. The expression levels of mRNA, the survival of cells, apoptosis, and cell migration were evaluated by real-time quantitative polymerase chain reaction, flow cytometry, and scratch wound.

RESULTS

Degradation of NEAT1 by CRISPR/cas9 significantly suppressed the gene's expression rate, arrested cell cycle in the G0/G1 phase, and a significant reduction in cell number in the S phase (P < 0.05). Degradation of NEAT1 by CRISPR/cas9 also restrained the ability to migrate in transfected cells compared to the control group (P < 0.01). Knockout of NEAT1 via impact on miR-34a gene expression induced apoptosis of AGS cells (P < 0.05) with increasing in the FAS level and total apoptosis (P < 0.001).

CONCLUSIONS

Findings suggest that NEAT1 plays a vital role in cellular mechanisms of GC's occurrence and can serve as a new treatment target in GC.

Biological Therapy with Complementary and Alternative Medicine in Innocuous Integrative Oncology: A Case of Cervical Cancer

Good medicine is based on good science, inquiry driven and open to new paradigms. For a complex disease such as cancer, a complex treatment regime that is well structured and multifactorial is indispensable. In the present day, Complementary and Alternative Medicine (CAM) therapies are being used frequently for cancer, alongside modern biological therapies and allopathic medicine, in what is called integrative oncology. In all conscience, the use of natural, less invasive interventions whenever possible is ideal. However, a comprehensive understanding of not only the etiopathology of individual cancers, but also the detailed genetic and epigenetic characteristics, the cancer hallmarks, that clearly show the blueprint of the cancer phenotype is a requisite. Different tumors have a common behavioral pattern, but their specific features at the genetic and epigenetic levels vary to a great extent. Henceforth, with so many failed attempts to therapy, drug formulations and combinations need a focused pre-assessment of the inherent features of individual cancers to destroy the tumors holistically by targeting these features. This review therefore presents innocuous therapeutic regimes by means of CAM and integrative medicine approaches that can specifically target the hallmarks of cancer, using the case of cervical cancer.

Ginkgoic acid impedes gastric cancer cell proliferation, migration and EMT through inhibiting the SUMOylation of IGF-1R

The imbalance of SUMOylation is related to different cancers, including gastric cancer (GC). Ginkgolic acid (GA) inhibits the growth and invasion of many cancer cells, and it has been reported to restrain SUMOylation. However, the role of GA in GC and whether it functions through SUMOylation remains to be clarified. Our research revealed that GA (15:1) inhibited cell proliferation, migration, epithelial-mesenchymal transition (EMT) and overall protein SUMOylation in BGC823 and HGC27 cells. In addition, knockdown of SUMO1 (small ubiquitin-like modifier) instead of SUMO2/3 played a similar role to GA in cell behaviors. Besides, nuclear IGF-1R (insulin-like growth factor 1 receptor) expression was markedly upregulated in GC cells compared to normal gastric epithelial cells. GA prevented IGF-1R from binding to SUMO1, thereby suppressing its nuclear accumulation. Further research found that IGF-1R directly bound to SNAI2 (snail family zinc finger 2) promoter. The interference of IGF-1R downregulated the mRNA and protein levels of SNAI2, while the overexpression of SUMO1, IGF-1R and UBC9 (SUMO-conjugating enzyme) played the opposite role. Furthermore, the co-transfection of SUMO1, UBC9 and IGF-1R vectors or the overexpression of SNAI2 reversed the inhibitory effects of GA on cell proliferation, migration and EMT. Finally, GA impeded the growth of GC xenografts and decreased the expression of nuclear IGF-1R and SNAI2 in vivo. In conclusion, these findings demonstrated that GA hindered the progression of GC by inhibiting the SUMOylation of IGF-1R. Thus, GA might be a promising therapeutic for GC.

EMT signaling: potential contribution of CRISPR/Cas gene editing

Epithelial to mesenchymal transition (EMT) is a complex plastic and reversible cellular process that has critical roles in diverse physiological and pathological phenomena. EMT is involved in embryonic development, organogenesis and tissue repair, as well as in fibrosis, cancer metastasis and drug resistance. In recent years, the ability to edit the genome using the clustered regularly interspaced palindromic repeats (CRISPR) and associated protein (Cas) system has greatly contributed to identify or validate critical genes in pathway signaling. This review delineates the complex EMT networks and discusses recent studies that have used CRISPR/Cas technology to further advance our understanding of the EMT process.

Exosomal miR-155-5p promotes proliferation and migration of gastric cancer cells by inhibiting TP53INP1 expression

Exosomal microRNA (miRNA) secreted by tumor cells plays an important biological role in tumorigenesis and development. We aimed to explore the effects of exosomal miR-155-5p in gastric cancer (GC) and understand its mechanism of action in GC progression. We isolated exosomes from the human gastric mucosal epithelial cell line GES-1 and gastric cancer cell line AGS, and then identified them according to their surface markers by flow cytometry. Later, we detected the miR-155-5p expression levels in tissues and isolated exosomes using RT-qPCR. Bioinformatics analysis showed that miR-155-5p directly binds to the 3' untranslated region (3'-UTR) of tumor protein p53-induced nuclear protein 1 (TP53INP1) mRNA. We also investigated whether the miR-155-5p-rich exosomes caused changes in cell cycle, proliferation, and migration in AGS cells. In this study, we found that the levels of miR-155-5p were significantly increased in GC tissues and AGS cells, and that the TP53INP1 protein level was downregulated in GC tissues using IHC and IFC. TP53INP1 was found to be directly regulated by miR-155-5p following a dual luciferase-based reporter assay. After co-culturing with the isolated miR-155-5p-rich exosomes, the proliferation and migration capabilities of AGS cells were enhanced. Thus, our results reveal that exosomal miR-155-5p acts as an oncogene by targeting TP53INP1 mRNA in human gastric cancer.

Update on gastric cancer treatments and gene therapies

Gastric cancer is an active topic of clinical and basic research due to high morbidity and mortality. To date, gastrectomy and chemotherapy are the only therapeutic options for gastric cancer patients, but drug resistance, either acquired or primary, is the main cause for treatment failure. Differences in development and response to cancer treatments have been observed among ethnically diverse GC patient populations. In spite of major incidence, GC Asian patients have a significantly better prognosis and response to treatments than Caucasian ones due to genetic discordances between the two populations. Gene therapy could be an alternative strategy to overcome such issues and especially CRISPR/Cas9 represents one of the most intriguing gene-editing system. Thus, in this review article, we want to provide an update on the currently used therapies for the treatment of advanced GC. Graphical abstract.

Induction of G0/G1 phase arrest and apoptosis by CRISPR/Cas9-mediated knockout of CDK2 in A375 melanocytes

Cutaneous melanoma is one of the most common malignant skin tumors, with a continuously increasing incidence. Cyclin-dependent kinase (CDK) 2 is a key regulator of G1-S transition and modulation of G2 progression; however, its role in cancer is a matter of debate. In the present study, a lentivirus expressing single-guide RNA (sgRNA) was constructed to knock out CDK2 using CRISP/Cas9 technology, in order to confirm the role of CDK2 in A375 human melanoma cells. The results demonstrated that CDK2 knockout induced G0/G1 phase arrest and early apoptosis by downregulating the expression of CDK4 and cyclin A2, and by upregulating the expression of cyclin D1. These results suggest that therapeutic strategies designed to target CDK2 using CRISP/Cas9 may improve the treatment outcome of cutaneous melanoma.

CRISPR/Cas9-mediated knockout of NSD1 suppresses the hepatocellular carcinoma development via the NSD1/H3/Wnt10b signaling pathway

Background

The NSD family of histone lysine methyltransferases have emerged as important biomarkers that participate in a variety of malignancies. Recent evidence has indicated that somatic dysregulation of the nuclear receptor binding SET domain-containing protein 1 (NSD1) is associated with the tumorigenesis in HCC, suggesting that NSD1 may serve as a prognostic target for this malignant tumor. However, its mechanism in human hepatocellular carcinoma (HCC), the major primary malignant tumor in the human liver, remains unclear. Hence, we investigated how NSD1 regulated HCC progression via regulation of the Wnt/β-catenin signaling pathway.

Methods

Reverse transcription quantitative polymerase chain reaction (RT-qPCR) and Western blot analysis was performed to identify the expression of NSD1 in HCC cells and clinically obtained tissues. The relationship between NSD1 expression and prognosis was analyzed by Kaplan-Meier survival curve. Further, a NSD1 knockout cell line was constructed by CRISPR/Cas9 genomic editing system, which was investigated in a battery of assays such as HCC cell proliferation, migration and invasion, followed by the investigation into NSD1 regulation on histone H3, Wnt10b and Wnt/β-catenin signaling pathway via ChIP. Finally, a nude mouse xenograft model was conducted in order to assess tumorigenesis affected by NSD1 knockout in vivo.

Results

NSD1 was overexpressed in HCC tissues and cell lines in association with poor prognosis. Knockout of NSD1 inhibited the proliferation, migration and invasion abilities of HCC cells. CRISPR/Cas9-mediated knockout of NSD1 promoted methylation of H3K27me3 and reduced methylation of H3K36me2, which inhibited Wnt10b expression. The results thereby indicated an inactivation of the Wnt/β-catenin signaling pathway suppressed cell proliferation, migration and invasion in HCC. Moreover, these in vitro findings were reproduced in vivo on tumor xenograft in nude mice.

Conclusion

In conclusion, the study provides evidence that CRISPR/Cas9-mediated NSD1 knockout suppresses HCC cell proliferation and migration via the NSD1/H3/Wnt10b signaling pathway, suggesting that NSD1, H3 and Wnt10b may serve as potential targets for HCC.