UHRF1-mediated ubiquitination of nonhomologous end joining factor XLF promotes DNA repair in human tumor cells.

UHRF1 (Ubiquitin-like with PHD and Ring Finger domains 1) is a crucial E3 ubiquitin ligase and epigenetic regulator with pivotal roles in various biological processes, including the maintenance of DNA methylation, regulation of gene expression, and facilitation of DNA damage repair. In this study, we unveil that UHRF1 interacts with the nonhomologous end joining factor XLF (also known as Cernunnos) following DNA double strand breaks in HeLa cells. Furthermore, we demonstrate that UHRF1 catalyzes lysine 63-linked polyubiquitination of XLF, rather than lysine 48-linked polyubiquitination. Notably, this polyubiquitination of XLF by UHRF1 does not affect its protein stability; instead, it enhances the recruitment of XLF to the sites of DNA damage. These findings shed light on the role of UHRF1 as a novel regulator of DNA repair through XLF in tumor cells.

SCARNA10 regulates p53 acetylation-dependent transcriptional activity.

The tumor suppressor p53 is involved in variety of cell progresses including cell cycle arrest, apoptosis, DNA repair, senescence, cell metabolism and ferroptosis. Here, we identified lncRNA SCARNA10 (Small Cajal Body-Specific RNA 10) as a novel cellular factor that interacts with the DNA binding domain (DBD) of p53. Upon binding the DBD of p53 and CREB-binding protein (CBP), SCARNA10 promotes the acetylation of p53, and activates p53-mediated transcriptional activation. Overexpress or knockdown SCARNA10 leads to up (or down)-regulation of p53-mediated transcriptional activation, whereas not affecting p53 protein levels. Moreover, SCARNA10 directly activates transcription by increasing the acetylation of p53 C-terminal domain (CTD) without affecting p53 phosphorylation at Ser15. These results indicate that SCARNA10 is a novel factor which regulates p53 acetylation-dependent transcriptional activity and tumor suppression.

The role of fatty acid ß-oxidation in lymphangiogenesis.

Lymphatic vessels are lined by lymphatic endothelial cells (LECs), and are critical for health. However, the role of metabolism in lymphatic development has not yet been elucidated. Here we report that in transgenic mouse models, LEC-specific loss of CPT1A, a rate-controlling enzyme in fatty acid ß-oxidation, impairs lymphatic development. LECs use fatty acid ß-oxidation to proliferate and for epigenetic regulation of lymphatic marker expression during LEC differentiation. Mechanistically, the transcription factor PROX1 upregulates CPT1A expression, which increases acetyl coenzyme A production dependent on fatty acid ß-oxidation. Acetyl coenzyme A is used by the histone acetyltransferase p300 to acetylate histones at lymphangiogenic genes. PROX1-p300 interaction facilitates preferential histone acetylation at PROX1-target genes. Through this metabolism-dependent mechanism, PROX1 mediates epigenetic changes that promote lymphangiogenesis. Notably, blockade of CPT1 enzymes inhibits injury-induced lymphangiogenesis, and replenishing acetyl coenzyme A by supplementing acetate rescues this process in vivo.

Noncoding RNAs in gastric cancer: implications for drug resistance.

Gastric cancer is the fourth most common malignancy and the third leading cause of cancer-related deaths worldwide. Advanced gastric cancer patients can notably benefit from chemotherapy including adriamycin, platinum drugs, 5-fluorouracil, vincristine, and paclitaxel as well as targeted therapy drugs. Nevertheless, primary drug resistance or acquisition drug resistance eventually lead to treatment failure and poor outcomes of the gastric cancer patients. The detailed mechanisms involved in gastric cancer drug resistance have been revealed. Interestingly, different noncoding RNAs (ncRNAs), such as microRNAs (miRNAs), long noncoding RNAs (lncRNAs) and circular RNAs (circRNAs), are critically involved in gastric cancer development. Multiple lines of evidences demonstrated that ncRNAs play a vital role in gastric cancer resistance to chemotherapy reagents and targeted therapy drugs. In this review, we systematically summarized the emerging role and detailed molecular mechanisms of ncRNAs impact drug resistance of gastric cancer. Additionally, we propose the potential clinical implications of ncRNAs as novel therapeutic targets and prognostic biomarkers for gastric cancer.

The emerging role of microRNAs and long noncoding RNAs in drug resistance of hepatocellular carcinoma.

Hepatocellular carcinoma (HCC) is the fifth most common malignancy worldwide and the second most lethal human cancer. A portion of patients with advanced HCC can significantly benefit from treatments with sorafenib, adriamycin, 5-fluorouracil and platinum drugs. However, most HCC patients eventually develop drug resistance, resulting in a poor prognosis. The mechanisms involved in HCC drug resistance are complex and inconclusive. Human transcripts without protein-coding potential are known as noncoding RNAs (ncRNAs), including microRNAs (miRNAs), small nucleolar RNAs (snoRNAs), long noncoding RNAs (lncRNAs) and circular RNA (circRNA). Accumulated evidences demonstrate that several deregulated miRNAs and lncRNAs are important regulators in the development of HCC drug resistance which elucidates their potential clinical implications. In this review, we summarized the detailed mechanisms by which miRNAs and lncRNAs affect HCC drug resistance. Multiple tumor-specific miRNAs and lncRNAs may serve as novel therapeutic targets and prognostic biomarkers for HCC.

Circulating tumor DNA measurement provides reliable mutation detection in mice with human lung cancer xenografts.

Genotype-directed targeted therapy has become one of the standard treatment options for non-small cell lung cancer (NSCLC). There have been numerous limitations associated with mutation analysis of tissue samples. Consequently, mutational profile analysis of circulating cell-free DNA (cfDNA) by highly sensitive droplet digital PCR (ddPCR) assay has been developed. Possibly due to differences in cfDNA concentrations, previous studies have shown numerous discrepancies in mutation detection consistency between tissue and cfDNA. In order to rigorously analyze the amount of cfDNA needed, we constructed 72 athymic nude mice xenografted with NCI-H1975 (harboring a EGFR T790M mutation) or NCI-H460 (harboring a KRAS Q61H mutation) human NSCLC. We thoroughly investigated the relationship between plasma cfDNA using Q-PCR targeting human long interspersed nuclear element-1 (LINE-1) retrotransposon and the mouse ACTB gene, and the accuracy of mutation detection by ddPCR at different times post-graft. Our results show that the concentration and fragmentation of human (tumor) derived cfDNA (hctDNA) were positively correlated with tumor weight, but not with mouse-derived cfDNA (mcfDNA). Quantification of cfDNA by Q-PCR depends on the amplified target length. Mutation copies in plasma of per milliliter were positively linked to tumor weight, hctDNA level and hctDNA/mcfDNA ratio, respectively. Furthermore, tumor weight, hctDNA level and ratio of hctDNA/mcfDNA were significantly higher in cfDNA mutation-positive mice than in negative mice. Also, our data indicate that when plasma hctDNA level and hctDNA/mcfDNA ratio reach a certain level in xenografted mice, plasma cfDNA mutation can be detected. In summary, the present study suggests that determination of ctDNA levels may be essential for reliable mutation detection by analysis of cfDNA.

Circulating exosomes contain protein biomarkers of metastatic non-small-cell lung cancer.

The present study aimed to investigate the overall changes in exosomal proteomes in metastatic and non-metastatic non-small-cell lung cancers (NSCLC) and healthy human serum samples, and evaluate the potential of serum exosomal biomarkers to predict NSCLC metastasis. Tandem mass tags combined with multidimensional liquid chromatography and mass spectrometry analysis were used for screening the proteomic profiles of serum samples. Quantitative proteome, significant pathway, and functional categories of patients with metastatic and non-metastatic NSCLC and healthy donors were investigated. In total, 552 proteins of the 628 protein groups identified were quantified. Bioinformatics analysis indicated that quantifiable proteins were mainly involved in multiple biological functions, metastasis-related pathways. Moreover, lipopolysaccharide-binding proteins (LBP) in the exosomes were found to be well distinguished between patients with metastatic and patients with non-metastatic NSCLC. Area under the curve (AUC) was 0.803 with a sensitivity of 83.1% and a specificity of 67% (P < .0001). Circulating LBP were also well distinguishable between metastatic and non-metastatic NSCLC, the AUC was 0.683 with a sensitivity of 79.5% and a specificity of 47.2% (P = .005). This novel study provided a reference proteome map for metastatic NSCLC. Patients with metastatic and non-metastatic NSCLC differed in exosome-related proteins in the serum. LBP might be promising and effective candidates of metastatic NSCLC.

miR-134 inhibits non-small cell lung cancer growth by targeting the epidermal growth factor receptor.

The epidermal growth factor receptor (EGFR) is frequently activated in a wide range of solid tumours and represents an important therapeutic target. MicroRNAs (miRNAs) have recently been recognized as a rational and potential modality for anti-EGFR therapies. However, more EGFR-targeting miRNAs need to be explored. In this study, we identified a novel EGFR-targeting miRNA, miRNA-134 (miR-134), in non-small-cell lung cancer (NSCLC) cell lines. Luciferase assays confirmed that EGFR is a direct target of miR-134. In addition, the overexpression of miR-134 inhibited EGFR-related signaling and suppressed NSCLC cells proliferation by inducing cell cycle arrest and/or apoptosis, suggesting that miR-134 functions as a tumour suppressor in NSCLC. Further mechanistic investigation including RNAi and rescue experiments suggested that the down-regulation of EGFR by miR-134 partially contributes to the antiproliferative role of miR-134. Last, in vivo experiments demonstrated that miR-134 suppressed tumour growth of A549 xenograft in nude mice. Taken together, our findings suggest that miR-134 inhibits non-small cell lung cancer growth by targeting the EGFR.

Angiogenesis revisited - role and therapeutic potential of targeting endothelial metabolism.

Clinically approved therapies that target angiogenesis in tumors and ocular diseases focus on controlling pro-angiogenic growth factors in order to reduce aberrant microvascular growth. Although research on angiogenesis has revealed key mechanisms that regulate tissue vascularization, therapeutic success has been limited owing to insufficient efficacy, refractoriness and tumor resistance. Emerging concepts suggest that, in addition to growth factors, vascular metabolism also regulates angiogenesis and is a viable target for manipulating the microvasculature. Recent studies show that endothelial cells rely on glycolysis for ATP production, and that the key glycolytic regulator 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase 3 (PFKFB3) regulates angiogenesis by controlling the balance of tip versus stalk cells. As endothelial cells acquire a tip cell phenotype, they increase glycolytic production of ATP for sprouting. Furthermore, pharmacological blockade of PFKFB3 causes a transient, partial reduction in glycolysis, and reduces pathological angiogenesis with minimal systemic harm. Although further assessment of endothelial cell metabolism is necessary, these results represent a paradigm shift in anti-angiogenic therapy from targeting angiogenic factors to focusing on vascular metabolism, warranting research on the metabolic pathways that govern angiogenesis.

Survivin mRNA-circulating tumor cells are associated with prostate cancer metastasis.

Detection of circulating tumor cells (CTCs) has been made to develop reliable assays for early diagnosis of various cancers. Overexpression of survivin in cancer cells is strongly associated with tumor progression. Although upregulation of survivin is observed in various tumors, its expression profile in the peripheral blood of prostate cancer (PCa) patients has not yet been investigated. In this study, we validated the application of survivin as the tumor marker to detect CTC and assessed its utility for diagnosis of PCa distant metastasis. Immunohistochemistry and quantitative real-time PCR (QRT-PCR) were performed to confirm the levels of surviving expression in PCa tissues. In addition, CTC values in 3 mL of peripheral blood from PCa patients, benign prostate hyperplasia (BPH) patients, and normal controls were also measured by the survivin-targeted PCR. Our results showed that surviving was overexpressed in PCa tissues. The median levels of blood surviving mRNA of PCa patients, BPH patients, and normal controls were 5.67 (range from 0 to 12.46), 2.24 (range from 0 to 6.55), and 1.85 (range from 0 to 3.82), respectively. The levels of survivin are positively associated with PCa distant metastasis. Our results concluded that quantitation of CTCs through survivin-PCR could be a promising marker for diagnosis of PCa metastasis.

Twist may be associated with invasion and metastasis of hypoxic NSCLC cells.

Hypoxia promotes tumor invasion and metastasis via multiple mechanisms, including epithelial-mesenchymal transition (EMT). Twist, an EMT regulator, has been disclosed to associate with invasion and metastasis as well as poor prognosis of many malignancies. However, it remains undefined whether Twist is involved in invasion and metastasis of hypoxic non-small cell lung cancer (NSCLC). In this study, protein levels of Twist, hypoxia-inducible factor-1α (HIF-1α), and EMT markers (E-cadherin and vimentin) were examined by immunohistochemistry in 76 lung cancer tissues from NSCLC patients. Expression of Twist and its correlation with HIF-1α, E-cadherin, and vimentin were analyzed. Small interfering RNA (siRNA) against Twist was used to knockdown Twist expression in hypoxic NSCLC cells, A549 and NCI-H460. Cellular invasion and protein levels of Twist, E-cadherin, and vimentin were evaluated by matrigel invasion assay and Western blot, respectively. Our results showed that in clinical samples, there was a significant association between Twist expression and differentiation degree, lymph node metastasis, and TNM stage. Correlation analysis demonstrated that expression of Twist was negatively correlated with E-cadherin expression, but positively associated with HIF-1α and vimentin expression. In cultured NSCLC cells, Twist messenger RNA (mRNA) and protein levels were upregulated under hypoxia, while knockdown of Twist suppressed potentiated invasion and expression of mesenchymal marker vimentin induced by hypoxia. Protein level of increased epithelial marker E-cadherin was shown along with Twist downregulation. These findings suggest that Twist promoting hypoxic invasion and metastasis of NSCLC may be associated with altered expression of EMT markers. Inhibition of Twist may be of therapeutic significance.

Morphine and ketamine inhibit immune function of gastric cancer patients by increasing percentage of CD4(+)CD25(+)Foxp3(+) regulatory T cells in vitro.

BACKGROUND: There is conflicting evidence regarding effects of anesthetic and analgesic drugs on immune function of cancer patients. This study was designed to observe changes of T cell subpopulations in the gastric cancer (GC) patients and to assess effects of morphine and ketamine on the CD4(+) T cells, CD8(+) T cells, and regulatory T cells (Tregs) populations obtained from the GC patients in vitro. METHODS: The peripheral blood samples from 20 GC patients and 20 healthy volunteers were obtained. The peripheral blood mononuclear cells were isolated and incubated in a solution containing phorbol-myristate-acetate and ionomycin (2 µL/mL) in the presence or absence of morphine (50 ng/mL) or different-concentration ketamine (25, 50, and 100 µM). The CD4(+) T cells, CD8(+) T cells, and Tregs were determined using the flow cytometric assay. RESULTS: The percentages of CD8(+) T cells were significantly decreased, but the ratio of CD4(+)/CD8(+) T cells and Tregs populations was significantly increased in the GC control group compared with the normal control group (P < 0.05). The ratio of CD4(+)/CD8(+) T cells was significantly increased in the groups M and K3 compared with the control group (P < 0.05) but was significantly decreased in the group K1 compared with the group K3. The percentage of Tregs was significantly increased in the groups M, K1, K2, and K3 compared with the control group. With the increased concentrations, ketamine increased the number of Tregs. CONCLUSIONS: GC shifts the balance of CD4(+)/CD8(+) T cells toward CD4(+) T cells and increases the Tregs populations by inducing immune responses. Morphine increases the ratio of CD4(+)/CD8(+) T cells and Tregs populations. Ketamine affects the ratio of CD4(+)/CD8(+) T cells and Tregs populations in a dose-dependent model.

Photodynamic Modulation of Endoplasmic Reticulum and Mitochondria Network Boosted Cancer Immunotherapy.

Immunogenic cell death (ICD) represents a promising approach for enhancing tumor therapy efficacy by inducing antitumor immune response. However, current ICD inducers often have insufficient endoplasmic reticulum (ER) enrichment and ineffectiveness in tumor immune escape caused by ER-mitochondria interaction. In this study, a kind of photoactivatable probe, THTTPy-PTSA, which enables sequential targeting of the ER and mitochondria is developed. THTTPy-PTSA incorporates p-Toluenesulfonamide (PTSA) for ER targeting, and upon light irradiation, the tetrahydropyridine group undergoes a photo oxidative dehydrogenation reaction, transforming into a pyridinium group that acts as a mitochondria-targeting moiety. The results demonstrate that THTTPy-PTSA exhibits exceptional subcellular translocation from the ER to mitochondria upon light irradiation treatment, subsequently triggers a stronger ER stress response through a cascade-amplification effect. Importantly, the augmented ER stress leads to substantial therapeutic efficacy in a 4T1 tumor model by eliciting the release of numerous damage-associated molecular patterns, thereby inducing evident and widespread ICD, consequently enhancing the antitumor immune efficacy. Collectively, the findings emphasize the pivotal role of photodynamic modulation of the ER-mitochondria network, facilitated by THTTPy-PTSA with precise spatial and temporal regulation, in effectively bolstering the antitumor immune response. This innovative approach presents a promising alternative for addressing the challenges associated with cancer immunotherapy.

A unique circulating microRNA pairs signature serves as a superior tool for early diagnosis of pan-cancer.

Cancer remains a major burden globally and the critical role of early diagnosis is self-evident. Although various miRNA-based signatures have been developed in past decades, clinical utilization is limited due to a lack of precise cutoff value. Here, we innovatively developed a signature based on pairwise expression of miRNAs (miRPs) for pan-cancer diagnosis using machine learning approach. We analyzed miRNA spectrum of 15832 patients, who were divided into training, validation, test, and external test sets, with 13 different cancers from 10 cohorts. Five different machine-learning (ML) algorithms (XGBoost, SVM, RandomForest, LASSO, and Logistic) were adopted for signature construction. The best ML algorithm and the optimal number of miRPs included were identified using area under the curve (AUC) and youden index in validation set. The AUC of the best model was compared to previously published 25 signatures. Overall, Random Forest approach including 31 miRPs (31-miRP) was developed, proving highly efficient in cancer diagnosis across different datasets and cancer types (AUC range: 0.980-1.000). Regarding diagnosis of cancers at early stage, 31-miRP also exhibited high capacities, with AUC ranging from 0.961 to 0.998. Moreover, 31-miRP exhibited advantages in differentiating cancers from normal tissues (AUC range: 0.976-0.998) as well as differentiating cancers from corresponding benign lesions. Encouragingly, comparing to previously published 25 different signatures, 31-miRP also demonstrated clear advantages. In conclusion, 31-miRP acts as a powerful model for cancer diagnosis, characterized by high specificity and sensitivity as well as a clear cutoff value, thereby holding potential as a reliable tool for cancer diagnosis at early stage.

Nanoreceptors promote mutant p53 protein degradation by mimicking selective autophagy receptors.

In some cancers mutant p53 promotes the occurrence, development, metastasis and drug resistance of tumours, with targeted protein degradation seen as an effective therapeutic strategy. However, a lack of specific autophagy receptors limits this. Here, we propose the synthesis of biomimetic nanoreceptors (NRs) that mimic selective autophagy receptors. The NRs have both a component for targeting the desired protein, mutant-p53-binding peptide, and a component for enhancing degradation, cationic lipid. The peptide can bind to mutant p53 while the cationic lipid simultaneously targets autophagosomes and elevates the levels of autophagosome formation, increasing mutant p53 degradation. The NRs are demonstrated in vitro and in a patient-derived xenograft ovarian cancer model in vivo. The work highlights a possible direction for treating diseases by protein degradation.

BTG2 overexpression increases the radiosensitivity of breast cancer cells in vitro and in vivo.

Antiproliferative gene B-cell translocation gene, member 2 (BTG2) is a member of the BTG/TOB antiproliferative gene family. In this study, we investigated the effect of BTG2 gene overexpression on the radiosensitivity of breast cancer cells in vitro and in vivo. Results show that in human breast cancer cell line MCF-7 stably overexpressing BTG2 gene, cell sensitivity to ionizing radiation increased. The MCF-7-BTG2 cells were more susceptible to radiation-caused apoptosis with decreased cyclin B1, cyclin D1, Ku70, FEN-1, and XRCC1 protein expression as well as increased BAX protein expression. The findings indicate for the first time that BTG2 can improve the radiosensitivity of breast cancer cells by affecting cell cycle distribution, enhancing radiation-induced apoptosis, and inhibiting DNA repair-related protein expression.

[Mechanism of the Notch1 signaling pathway regulating osteogenic factor influences lumbar disc calcification].

OBJECTIVE: To explore the mechanism of the Notch1 signaling pathway in regulating osteogenic factors and influencing lumbar disc calcification. METHODS: Primary annulus fibroblasts from SD rats were isolated and subcultured in vitro. The calcification-inducing factors bone morphogenetic protein-2 (BMP-2) and basic fibroblast growth factor (b-FGF) were added to separate groups to induce calcification, which were referred to as the BMP-2 group and the b-FGF group, respectively. A control group was also set up, which was cultured in normal medium. Subsequently, cell morphology and fluorescence identification, alizarin red staining, ELISA, and quantitative real-time polymerase chain reaction (QRT-PCR) were performed to determine the effect of calcification induction. Cell grouping was performed again, including the control group, the calcification group (adding the inducer BMP-2), the calcification + LPS group(adding the inducer BMP-2 and the Notch1 pathway activator LPS), and the calcification + DAPT group (adding the inducer BMP-2 and the Notch1 pathway inhibitor DAPT). Alizarin red staining and flow cytometry were used to detect cell apoptosis, ELISA was used to detect the content of osteogenic factors, and Western blot was used to detect the expression of BMP-2, b-FGF, and Notch1 proteins. RESULTS: The induction factor screening results showed that the number of mineralized nodules in fibroannulus cells in BMP-2 group and b-FGF group was significantly increased, and the increase was greater in the BMP-2 group Meanwhile, ELISA and Western blot results showed that BMP-2, b-FGF and mRNA expression levels of BMP-2, b-FGF and Notch1 in the induced group were significantly increased (P<0.01). The results of the mechanism of Notch1 signaling pathway affecting lumbar disc calcification showed that compared to calcified group, the number of fibroannulus cell mineralization nodules, apoptosis rate, BMP-2, b-FGF content, the expression levels of BMP-2, b-FGF, and Notch1 proteins were further increased significantly However, the number of mineralization nodules, apoptosis rate, BMP-2 and b-FGF levels, BMP-2, b-FGF and Notch1 protein expression levels were decreased in the calcified +DAPT group (P<0.05 or P<0.01). CONCLUSION: Notch1 signaling pathway promotes lumbar disc calcification through positive regulation of osteogenic factors.

Noncoding RNAs: an emerging modulator of drug resistance in pancreatic cancer.

Pancreatic cancer is the eighth leading cause of cancer-related deaths worldwide. Chemotherapy including gemcitabine, 5-fluorouracil, adriamycin and cisplatin, immunotherapy with immune checkpoint inhibitors and targeted therapy have been demonstrated to significantly improve prognosis of pancreatic cancer patients with advanced diseases. However, most patients developed drug resistance to these therapeutic agents, which leading to shortened patient survival. The detailed molecular mechanisms contributing to pancreatic cancer drug resistance remain largely unclear. The growing evidences have shown that noncoding RNAs (ncRNAs), including microRNAs (miRNAs), long noncoding RNAs (lncRNAs) and circular RNAs (circRNAs), are involved in pancreatic cancer pathogenesis and development of drug resistance. In the present review, we systematically summarized the new insight on of various miRNAs, lncRNAs and circRNAs on drug resistance of pancreatic cancer. These results demonstrated that targeting the tumor-specific ncRNA may provide novel options for pancreatic cancer treatments.

Effect of HMGB1 silencing on cell proliferation, invasion and apoptosis of MGC-803 gastric cancer cells.

High-mobility group box 1 (HMGB1) is a multifunctional protein with intranuclear and extracellular functions. Although HMGB1 is overexpressed in approximately 85% of gastric cancers, the role of HMGB1 in gastric cancer biology remains unclear. In this study, we investigate the effect of downregulation of HMGB1 on the biological behavior of gastric cancer cells. MGC-803 gastric cancer cells were transduced with HMGB1-specific RNAi lentiviral vectors. Real-time polymerase chain reaction and Western blot analysis of HMGB1 mRNA and protein, respectively, validated the silencing effects. HMGB1-specific silencing significantly decreased cell proliferation. The impact on proliferation was observed at the cell cycle level--the number of cells in the G0/G1 phase increased, whereas that in S and G2/M phases decreased. Cell cycle changes were accompanied by decreases in cyclin D1 expression. Furthermore, HMGB1 silencing sensitized cells to apoptosis that was induced by oxaliplatin and mediated by the caspase-3 pathway. Finally, silencing of HMGB1 expression significantly reduced cellular metastatic ability and MMP-9 expression in MGC-803 cells. In summary, HMGB1 not only plays an essential role in the proliferation and invasion of MGC-803 cells but also represents a potential target for the therapeutic intervention of gastric cancer.