Synthetic lethality of combined ULK1 defection and p53 restoration induce pyroptosis by directly upregulating GSDME transcription and cleavage activation through ROS/NLRP3 signaling.

BACKGROUND: High expression of ubiquitin ligase MDM2 is a primary cause of p53 inactivation in many tumors, making it a promising therapeutic target. However, MDM2 inhibitors have failed in clinical trials due to p53-induced feedback that enhances MDM2 expression. This underscores the urgent need to find an effective adaptive genotype or combination of targets. METHODS: Kinome-wide CRISPR/Cas9 knockout screen was performed to identify genes that modulate the response to MDM2 inhibitor using TP53 wild type cancer cells and found ULK1 as a candidate. The MTT cell viability assay, flow cytometry and LDH assay were conducted to evaluate the activation of pyroptosis and the synthetic lethality effects of combining ULK1 depletion with p53 activation. Dual-luciferase reporter assay and ChIP-qPCR were performed to confirm that p53 directly mediates the transcription of GSDME and to identify the binding region of p53 in the promoter of GSDME. ULK1 knockout / overexpression cells were constructed to investigate the functional role of ULK1 both in vitro and in vivo. The mechanism of ULK1 depletion to activate GSMDE was mainly investigated by qPCR, western blot and ELISA. RESULTS: By using high-throughput screening, we identified ULK1 as a synthetic lethal gene for the MDM2 inhibitor APG115. It was determined that deletion of ULK1 significantly increased the sensitivity, with cells undergoing typical pyroptosis. Mechanistically, p53 promote pyroptosis initiation by directly mediating GSDME transcription that induce basal-level pyroptosis. Moreover, ULK1 depletion reduces mitophagy, resulting in the accumulation of damaged mitochondria and subsequent increasing of reactive oxygen species (ROS). This in turn cleaves and activates GSDME via the NLRP3-Caspase inflammatory signaling axis. The molecular cascade makes ULK1 act as a crucial regulator of pyroptosis initiation mediated by p53 activation cells. Besides, mitophagy is enhanced in platinum-resistant tumors, and ULK1 depletion/p53 activation has a synergistic lethal effect on these tumors, inducing pyroptosis through GSDME directly. CONCLUSION: Our research demonstrates that ULK1 deficiency can synergize with MDM2 inhibitors to induce pyroptosis. p53 plays a direct role in activating GSDME transcription, while ULK1 deficiency triggers upregulation of the ROS-NLRP3 signaling pathway, leading to GSDME cleavage and activation. These findings underscore the pivotal role of p53 in determining pyroptosis and provide new avenues for the clinical application of p53 restoration therapies, as well as suggesting potential combination strategies.

APG-1252 combined with Cabozantinib inhibits hepatocellular carcinoma by suppressing MEK/ERK and CREB/Bcl-xl pathways.

BACKGROUND AND PURPOSE: Liver cancer is the fourth leading cause of cancer-related death worldwide, with hepatocellular carcinoma (HCC) being the most common type of primary liver cancer. APG-1252 is a small molecule inhibitor targeting Bcl-2 and Bcl-xl. However, its anti-tumor effects in HCC, alone or in combination with Cabozantinib, have not been extensively studied. EXPERIMENTAL: Approach: TCGA database analysis was used to analysis the gene expression levels of Bcl-2 and Bcl-xl in HCC tissues. Western blot was employed to detect the protein expression levels. And the inhibitory effects of APG-1252 and Cabozantinib on the proliferation of HCC cell lines was detected by CCK-8. The effect on the migration and invasion of HCC cells was verified by transwell assay. Huh7 xenograft model in nude mice was used to investigate the combination antitumor effect in vivo. KEY RESULTS: Our study demonstrated that APG-1252 monotherapy inhibited the proliferation and migration ability of HCC cells, and induced HCC cells apoptosis. The combination of APG-1252 and Cabozantinib showed significant synergistic antitumor effects. Furthermore, the in vivo experiment demonstrated that the combination therapy exerted a synergistic effect in delaying tumor growth, notably downregulating MEK/ERK phosphorylation levels. In terms of mechanism, Cabozantinib treatment caused an increase in the phosphorylation levels of CREB and Bcl-xl proteins, while the combination with APG-1252 mitigated this effect, thereby enhanced the antitumor effect of Cabozantinib. CONCLUSION AND IMPLICATIONS: Our findings suggest that APG-1252 in combination with Cabozantinib offers a more effective treatment strategy for HCC patients, warranting further clinical investigation.

Clinical outcomes and biomarker exploration of first-line PD-1 inhibitors plus chemotherapy in patients with low PD-L1-expressing of gastric or gastroesophageal junction adenocarcinoma.

BACKGROUND: The beneficial effects of first-line programmed death-1 (PD-1) inhibitors plus chemotherapy in patients with low programmed death-ligand 1 (PD-L1)-expressing advanced gastric or gastroesophageal junction (G/GEJ) adenocarcinoma are controversial. METHODS: We conducted a retrospective analysis of patients with G/GEJ adenocarcinoma who had undergone first-line treatment with PD-1 inhibitors plus chemotherapy between October 2017 and May 2022. The primary outcomes were objective response rate (ORR) and progression-free survival (PFS). SPSS software V27.0 was used for data analysis. RESULTS: Of 345 enrolled patients, 290 had measurable lesions. The overall ORR was 59.3%. PD-L1 status was available in 171 patients, and 67.8% of them were considered as low PD-L1 expression level (combined positive score (CPS) < 5). Patients with PD-L1 CPS < 5 showed a lower response rate (51.1% vs 70.8%, P = 0.024) and a worse PFS (P = 0.009) compared to those with PD-L1 CPS ≥ 5. In the PD-L1 low-expression cohort, patients with non-diffuse type, GEJ cancer, synchronous metastasis, distant lymph node metastasis, liver metastasis, non-peritoneal metastasis, and HER2 positive were significantly associated with higher response rates to PD-1 inhibitors plus chemotherapy (P < 0.05). The presence of peritoneal metastasis (P = 0.028) and diffuse type (P = 0.046) were identified as independent predictors of poor PFS in multivariate analysis of the PD-L1 CPS < 5 subgroup. When evaluated for correlation with overall survival (OS) in the PD-L1 low-expression subgroup, peritoneal metastasis was found to be the only independent prognostic factor of an increased risk of death (hazard ratio: 2.31, 95% CI 1.09-4.90; P = 0.029). CONCLUSIONS: PD-L1 CPS ≥ 5 is significantly associated with improved response and extended PFS in G/GEJ cancer patients treated with a combination of PD-1 inhibitors and chemotherapy. Specific subgroups within the low PD-L1-expressing population, such as those with non-diffuse-type tumors and without peritoneal metastases, may also benefit from immunotherapy combined with chemotherapy.

The relationship between brain metastasis and HER2 expression status in gastric cancer.

BACKGROUND: Brain metastasis (BM) in gastric cancer (GC) is underestimated, and human epidermal growth factor receptor 2 (HER2) overexpression is a durable poor prognostic factor. We explored the relationship between the two and made a survival analysis. METHODS: HER2 expression and BM status were collected from GC patients who were diagnosed between December 2009 and May 2021. We collected GC patients diagnosed between 2010 and 2016 from the SEER database. The primary endpoint was survival from the diagnosis of BM. Multivariable logistic regression was used to determine potential risk factors of BM at diagnosis in SEER database. Survival analysis was performed using the Kaplan-Meier method. RESULT: There were 513 HER2-positive GC patients, including 16 (3.1%) with BM. Among 38 brain metastasis GC patients we collected, 16 (42.1%) patients were HER2 positive. We collected 34,199 GC patients from the SEER database and there were 260 (0.76%) patients with BM at diagnosis. GC patients that are male, white, of younger age, with primary lesions located in the proximal stomach or with distant lymph nodes, liver, bone, or lung metastasis are more likely to develop BM. The median overall survival time from diagnosis of BM was 12.73 months, and the survival time from brain metastasis of HER2-positive patients was numerically shorter, though the difference was not significant (5.30 months vs.16.13 months, P = 0.28.) CONCLUSION: The incidence of BM in patients with HER2-positive gastric cancer is 4.08 times higher than that in general patients. The median overall survival time from BM is shorter for HER2-positive patients.

Novel prognostic model predicts overall survival in colon cancer based on RNA splicing regulation gene expression.

Colon cancer is the third most common cancer and the second leading cause of cancer-related death worldwide. Dysregulated RNA splicing factors have been reported to be associated with tumorigenesis and development in colon cancer. In this study, we interrogated clinical and RNA expression data of colon cancer patients from The Cancer Genome Atlas (TCGA) dataset and the Gene Expression Omnibus (GEO) database. Genes regulating RNA splicing correlated with survival in colon cancer were identified and a risk score model was constructed using Cox regression analyses. In the risk model, RNA splicing factor peroxisome proliferator-activated receptor-γ coactivator-1α (PPARGC1) is correlated with a good survival outcome, whereas Cdc2-like kinase 1(CLK1), CLK2, and A-kinase anchor protein 8-like (AKAP8L) with a bad survival outcome. The risk model has a good performance for clinical prognostic prediction both in the TCGA cohort and the other two validation cohorts. In the tumor microenvironment (TME) analysis, the immune score was higher in the low-risk group, and TME-related pathway gene expression was also higher in low-risk group. We further verified the mRNA and protein expression levels of these four genes in the adjacent nontumor, tumor, and liver metastasis tissues of colon cancer patients, which were consistent with bioinformatics analysis. In addition, knockdown of AKAP8L can suppress the proliferation and migration of colon cancer cells. Animal studies have also shown that AKAP8L knockdown can inhibit tumor growth in colon cancer in vivo. We established a prognostic risk model for colon cancer based on genes related to RNA splicing regulation and uncovered the role of AKAP8L in promoting colon cancer progression.

High AKAP8L expression predicts poor prognosis in esophageal squamous cell carcinoma.

BACKGROUND: Esophageal squamous cell carcinoma (ESCC) is a severe disease with high mortality, and is associated with poor prognosis and frequent lymphatic metastasis. Therefore, prognostic indicators for ESCC are urgently needed. A-kinase anchor-protein 8-like (AKAP8L) is a member of the A kinase anchor-protein (AKAPs) family and is overexpressed in many cancers. However, the role of AKAP8L in ESCC remains unclear. The aim of this study is to investigate the expression patterns and prognostic value of AKAP8L in ESCC. METHODS: The mRNA expression of AKAP8L was analyzed from the dataset of The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO). Immunohistochemistry was applied to detect the AKAP8L expression in tissue microarray. Pearson's chi-square test was carried out for the correlation analysis of clinicopathological features and AKAP8L expression. The prognostic significance of clinicopathological features and AKAP8L expression was determined by univariate and multivariate Cox hazard models. Kaplan-Meier survival curve was used for survival analysis. RESULTS: We found that the mRNA level of AKAP8L was higher in tumor tissues than in adjacent tissues in TCGA and GEO dataset. High AKAP8L expression was associated with poor overall survival (OS) in ESCC patients (p = 0.0039). Besides, AKAP8L expression was highly expressed in patients with lymph node metastasis detected by ESCC tissue microarray (p = 0.0014). The comparison of the different clinicopathological features of ESCC between high and low AKAP8L expression groups revealed that high AKAP8L expression was related to lymph node stage (p = 0.041). Kaplan-Meier survival analysis revealed that high AKAP8L expression indicates an unfavorable progression-free survival (PFS) and OS in ESCC patients (p < 0.0001). Univariate and multivariate analyses confirmed that AKAP8L was an independent prognostic factor for PFS and OS in ESCC (p = 0.003 and p < 0.0001). CONCLUSIONS: In conclusion, this study demonstrated that high expression of AKAP8L is associated with poor prognosis of ESCC and can be considered an independent risk factor for ESCC.

Gemcitabine and APG-1252, a novel small molecule inhibitor of BCL-2/BCL-XL, display a synergistic antitumor effect in nasopharyngeal carcinoma through the JAK-2/STAT3/MCL-1 signaling pathway.

Advanced nasopharyngeal carcinoma (NPC) has a poor prognosis, with an unfavorable response to palliative chemotherapy. Unfortunately, there are few effective therapeutic regimens. Therefore, we require novel treatment strategies with enhanced efficacy. The present study aimed to investigate the antitumor efficacy of APG-1252-M1, a dual inhibitor of BCL-2/BCL-XL, as a single agent and combined with gemcitabine. We applied various apoptotic assays and used subcutaneous transplanted NPC model to assess the in vitro and in vivo antitumor activity. Moreover, phospho-tyrosine kinase array was used to investigate the combined therapy's potential synergistic mechanism. In addition, further validation was performed using immunohistochemistry and western blotting. In vitro, we observed that APG-1252-M1 had moderate antitumor activity toward NPC cells; however, it markedly improved gemcitabine's ability to promote NPC cell apoptosis and suppress invasion, migration, and proliferation. Specifically, APG-1252 plus gemcitabine exhibited even remarkable antitumor activity in vivo. Mechanistically, the drug combination synergistically suppressed NPC by activating caspase-dependent pathways, blocking the phospho (p)-JAK-2/STAT3/MCL-1 signaling pathway, and inhibiting epithelial-mesenchymal transition. In conclusion, the results indicated that the combination of APG-1252 and gemcitabine has synergistic anticancer activities against NPC, providing a promising treatment modality for patients with NPC.

Relationship of HER2 Alteration and Microsatellite Instability Status in Colorectal Adenocarcinoma.

BACKGROUND: The impact of HER2 somatic mutations in colorectal carcinoma (CRC) has not been well studied and its relationship with microsatellite instability-high (MSI-H) is yet to be fully elucidated. MATERIALS AND METHODS: From February 2017 to February 2020, the data of patients with CRC who underwent next-generation sequencing and had detailed record of clinicopathological information were investigated. HER2 alteration and its relationship with MSI-H were analyzed. RESULTS: Among 731 patients who underwent sequencing, 55 patients (7.5%) had HER2 alteration, including 29 (4.0%) with HER2 somatic mutations, 24 (3.3%) with HER2 gene amplification, and 2 patients (0.2%) with both HER2 mutations and amplification. R678Q was the most common mutated kinase domain, and no HER2 kinase domain in-frame insertions/deletions were found in HER2 mutated cases. MSI-H was found in 5.2% of our cohort and 36.8% of MSI-H patients had HER2 mutation. For HER2 mutated cases, 48.3% were MSI-H, whereas none of the HER2 amplification cases were MSI-H. MSI-H patients with HER2 mutation had significantly worse median progression-free survival for programmed death-1 (PD-1) antibody than those without HER2 alteration (p = .036). CONCLUSION: High MSI-H rate was found in HER2 mutated cases, but no MSI-H was found in HER2 amplification cases. MSI-H patients with HER2 mutated had worse progression-free survival for PD-1 antibody than those without. IMPLICATIONS FOR PRACTICE: This study highlights the high microsatellite instability-high (MSI-H) rate in HER2 mutated cases but no MSI-H in HER2 amplification cases. Moreover MSI-H patients with HER2 mutated had worse progression-free survival for programmed death-1 antibody than those without. Further research to explore the internal relationship between HER2 alteration and MSI-H is needed.

Comparison of Immune Microenvironment Between Colon and Liver Metastatic Tissue in Colon Cancer Patients with Liver Metastasis.

BACKGROUND: Liver metastasis is an indicator of unfavorable responses to immunotherapy in colorectal cancer patients. However, the difference of immune microenvironment between primary tumors and liver metastases has not been well understood. PATIENTS AND METHODS: Fifty-four colon cancer with liver metastasis patients who received resection of both primary and metastasis lesions have been analyzed. The immune score is based on the density of infiltrating immune cells (CD3+ cell, CD8+ cell, CD11b+ cell, CD11c+ cell, and CD33+ cell) in the center and margin of the tumor. The expression of immune markers between the primary tumor and hepatic metastases was analyzed using Wilcoxon's signed rank test. RESULTS: All the five markers had higher expression in tumor margins than center tumor in both primary tumor and hepatic metastases lesions. The expression of CD11c and CD11b had no difference between metastatic lesions and primary tumor. In tumor margins, except CD11b, all the other 4 markers expressed significantly higher in hepatic metastases than in primary tumor. Intra-tumor, CD3 had higher expression in primary tumor than in hepatic metastases, while CD33 had higher expression in hepatic metastases than in primary tumor. CD8+ CD3+ cells of the total CD8+ cell population in primary tumor was significantly higher than in hepatic metastases (36.42% vs. 24.88%, p = 0.0069). CONCLUSIONS: The immune microenvironment between primary tumor and hepatic metastasis is different. More immunosuppressing cells in liver may partially explain why immunotherapy in colon cancer is less effective with liver metastatic disease.

A multi-kinase inhibitor APG-2449 enhances the antitumor effect of ibrutinib in esophageal squamous cell carcinoma via EGFR/FAK pathway inhibition.

Esophageal squamous cell carcinoma (ESCC) is one of the most common types of cancer in China, with poor prognosis and lack of effective targeted therapy. It has been reported that ibrutinib possesses anticancer activity in ESCC with MYC and/or ERBB2 amplification. Here we explored the synergistic antitumor effect of a novel multi-kinase inhibitor APG-2449 with ibrutinib in ESCC and clarified the mechanism of the combination effect through in vitro and in vivo experiment. We found that APG-2449 exerted antitumor effect in ESCC. APG-2449 combined with ibrutinib showed synergistic inhibition of cell viability in ESCC cell lines. APG-2449 combined with ibrutinib dramatically inhibited the proliferation and migration of ESCC cells. Furthermore, we observed that ibrutinib combined with APG-2449 could induce more cancer cells arrested in the G1/S phase and apoptosis. In terms of mechanism, ibrutinib alone could decrease the phosphorylation level of EGFR and its downstream pathway of MEK/ERK. The combination therapy of APG-2449 and ibrutinib could significantly down-regulate the phosphorylation level of MEK/ERK and AKT. In ESCC xenotransplantation models, single therapy with either ibrutinib or APG-2449 was equivalent in delaying tumor growth, while the combination therapy suppressed tumor growth more significantly. Our data strongly suggest that the combination therapy of APG-2449 and ibrutinib can provide an effective therapeutic strategy for ESCC patients, which deserved further clinical investigation.

MicroRNA-375 reverses the expression of PD-L1 by inactivating the JAK2/STAT3 signaling pathways in gastric cancer.

BACKGROUND: The mechanism of PD-L1 expression in gastric cancer patients remains unclear. microRNAs (miRs) have been reported to be crucial components of the crosstalk between tumor-immune cells and emerging evidence suggests that microRNA-375 (miR-375) is significantly downregulated in digestive system tumors, but its association with PD-L1 expression in gastric cancer remains to be determined. METHODS: The expression level of miR-375 was first investigated in human gastric cancer tissues and cell lines. Its effect on gastric cancer cell proliferation, migration, invasion, and apoptosis were evaluated in vitro via CCK8, colony formation assays, wound healing assays, transwell assays, and flow cytometry. In vivo experiments using immunodeficient BALB/c nude female mice were also performed. Luciferase reporter assays were employed to identify interactions between miR-375 and its target genes. RESULTS: Quantitative real-time PCR showed that the expression of miR-375 was negatively correlated with PD-L1 in gastric cancer tissues. The overexpression of miR-375 inhibited gastric cancer cell proliferation, migration, invasion, and the knockdown of miR-375 demonstrated opposite effects, both in vitro and in vivo. Luciferase reporter assays showed that miR-375 could bind to the 3'-UTR regions of JAK2 and an inverse association between miR-375 and JAK2/STAT3/PD-L1 expression in gastric cancer cell lines was also observed. In vivo experiments showed that miR-375-overexpression decreased the growth of xenograft tumors in immunodeficient BALB/c mice. CONCLUSIONS: miR-375 negatively regulates PD-L1 expression in gastric cancer via the JAK2/STAT3 signaling pathway and could be a promising novel therapeutic target in gastric cancer.

Observational cohort study of clinical outcome in Epstein-Barr virus associated gastric cancer patients.

BACKGROUND: Epstein-Barr virus-associated gastric cancer (EBVaGC) has unique clinicopathologic features and our present understanding of its treatment outcome is limited. Here, we investigated the clinical outcomes of resectable and metastatic EBVaGC cases with regards to their respective treatment. METHODS: We retrieved the data of EBVaGC patients treated at our center from October 2014 to June 2019. The primary endpoint was overall survival (OS). Secondary endpoints were disease-free survival (DFS) for stage I-III patients, progression-free survival (PFS) and objective response rate (ORR) for stage IV patients. RESULTS: Patients classified as stage I-III accounted for 83.7% of the total 197 cases analyzed. Two patients had mismatched repair-deficiency. The 5-year OS rate of the entire cohort was 63.51% [95% (confidence interval (CI): 52.31-72.76%]. Tumor-node-metastasis (TNM) stage and gastric stump cancer were identified as independent prognostic factors for OS. The 3- and 5-year DFS rate for stage I-III patients were 83.72% (95% CI: 75.86-89.19%) and 73.83% (95% CI: 60.39-83.32%), respectively. TNM stage III, neural invasion, lymphovascular invasion, and baseline plasma EBV-DNA positive were correlated with shorter DFS. The ORR and disease control rate (DCR) for metastatic EBVaGC patients to first-line therapy were 29.0% and 90.3% (median PFS: 9.8 months), respectively, and to second-line therapy were 25.0% and 75.0%, respectively. Seven patients received anti-PD1 therapy and had an ORR of 28.5% and a median PFS of 2.8 months. CONCLUSIONS: EBVaGC patients have few metastases, long DFS, and high DCR. TNM stage and gastric stump cancer were independent prognostic factors for OS.

Role of Systemic Treatment for Advanced/Metastatic Gastric Carcinoma in the Third-Line Setting: A Bayesian Network Analysis.

Background: Increasing evidences from phase II or III trials have proved that salvage systematic therapy, including chemotherapy, target therapy, or checkpoint inhibitor therapy can prolong survival in patients who do not succeed with second line therapy, yet there are no guidelines for the optimum third-line treatments. To compare the effectiveness and safety of current third-line therapies for metastatic Gastric Cancer (mGC), we conducted this network analysis. Methods: Literature up to Sep 30, 2019 were systematically searched and analyzed by a Bayesian fixed-effect model. Results: This study included seven randomized clinical trails which involved 2,655 patients. It turns out that for overall survival, nivolumab has the highest probability to be the optimal choice for overall survival (OS). For patients with no peritoneal metastases, the network meta-analysis showed that Nivolumab (HR:0.64; 95% CI: 0.48-0.85) and Trifluridine/tipiacil (HR:0.66; 95% CI: 0.51-0.86) were associated with significantly higher improvement in OS than placebo. However, patients with peritoneal metastases could not benefit from nivolumab, ramucirumab, or Trifluridine/tipiacil, when compared with a placebo. For progression-free survival, apatinib (850 mg) was the most likely candidate, followed by ramucirumab. Statistically, Apatinib (850 mg), Trifluridine/tipiacil, and SLC had higher incidences of high-grade adverse events (AEs) than placebo. Conclusion: Our findings demonstrate that nivolumab has the best balance between acceptability and effectiveness in the third line therapy for mGC.

Bcl-2/Bcl-xl inhibitor APG-1252-M1 is a promising therapeutic strategy for gastric carcinoma.

Gastric carcinoma is the third major cause of cancer-related death in China. Bcl-2 and other BH3 family proteins are critically important in the process of apoptosis pathway, which may be a promising target. APG-1252-M1 specifically connects to Bcl-2 and Bcl-xl. The antitumor effect of APG-1252-M1 in six gastric cancer cells was identified by the Cell Counting Kit-8 assay. The expression level of proapoptotic proteins was evaluated by Western blot. Meanwhile, the cell cycle and apoptosis distributions were analyzed by flow cytometry and JC-1. Xenograft models were used to investigate the roles of APG-1252-M1 in suppressing the growth of tumors and enhancing the chemotherapy antitumor effect. The antitumor effect of APG-1252-M1 was time- and dose-dependent and acted by initiating apoptosis. The change of cell cycle distribution was not discovered in gastric cancer cells treated with APG-1252-M1. APG-1252-M1 also exhibited synergy with chemotherapy in vivo. The combined group inhibited xenograft tumor growth more obviously than the other groups. Moreover, Ki-67 was remarkably decreased in the combination group compared to other groups. In conclusion, APG-1252-M1 had a strong antitumor effect by inducing apoptosis and was synergistic with chemotherapy.

More attention should be paid to adult gastric cancer patients younger than 35 years old: extremely poor prognosis was found.

Purpose: Several studies have reported controversial results about prognosis of gastric cancer in young age patients. The difference may partially result from variable definitions of young age. The aim of this study was to find out the relation between age and prognosis of gastric cancer patients, and to analyze the clinicopathological features and prognostic factors in young gastric cancer patients. Methods: Data queried for this analysis included GC patients from the Surveillance, Epidemiology, and End Results Program database from 1973 to 2014. Gastric cancer patients (N=79,505) diagnosed with an age≥18 were included. By combining patients with similar prognosis, we figured out 3 cutoff values of age, 35 years old, 65 years old and 75 years old. We divided patients into 4 groups: young age patients: 18-34 years; middle-age patients: 35-64 years; elderly patients: 65-74 years; extremely elderly patients: >74 years. GC patients from Sun Yat-sen University Cancer Center (SYSUCC) were used as external validation data. Results: The clinicopathological features of young age gastric cancer patients included: poor-differentiated, diffuse type of cancer, and advanced stage at diagnosis. The median survival of patients <35 years old was significantly lower than middle-age patients (35-64 years) and elderly patients (65-74 years) (12 months vs. 15 and 16 months, respectively, both p <0.001). Location of tumor, ethnicity, tumor size, surgery and TNM stage were independent prognostic factors by multivariate analysis in young patients. The poor prognosis for young patients remained valid in the SYSUCC database. Conclusions: Our results demonstrated that gastric cancer patients <35 years old had an extremely poor prognosis. Early detection of gastric cancer is of paramount importance in young age people.

A novel Bcl-2 inhibitor, BM-1197, induces apoptosis in malignant lymphoma cells through the endogenous apoptotic pathway.

BACKGROUND: Bcl-2 family members play an important role in the development of malignant lymphoma and can induce drug resistance in anticancer treatment. The development of small molecules targeting Bcl-2 family proteins may be a new strategy for the treatment of malignant lymphoma. In this study, we investigate the antitumor effect and cellular mechanism of a novel Bcl-2/Bcl-xL dual inhibitor, BM-1197, in DCBCL and Burkitt lymphoma cells. METHODS: The CCK-8 assay was used to detect cell viability. Apoptosis was determined by Hoechst 33258 staining and flow cytometry. The activity of caspase-3/caspase-9 was determined using a caspase-3/caspase-9 activity kit. Western blotting analysis was performed to evaluate the changes in protein expression. Functional analysis was performed via immunoprecipitation and siRNA interference. Human malignant lymphoma xenograft models in nude mice were established for in vivo efficacy detection. RESULTS: We find that BM-1197 exerts potent growth-inhibitory activity against lymphoma cells that harbor high expression of Bcl-2 and Bcl-xL in vitro and has a synergistic effect with chemotherapeutic drugs. Mechanistically, we see that the intrinsic apoptosis pathway is activated upon BM-1197 treatment. BM-1197 affects the protein interactions of Bak/Bcl-xl, Bim/Bcl-2, Bim/Bcl-xl, and PUMA/Bcl-2 and induces conformational changes in the Bax protein, which result in the activation of Bax and release of cytochrome c, activate caspase - 9, - 3, and - 7 and finally induce cell apoptosis. Furthermore, our data demonstrate that BM-1197 exhibits strong anti-tumor effects against established human malignant lymphoma xenograft models. CONCLUSIONS: Our study demonstrated BM-1197 exerts potent antitumor effects both in vitro and in vivo and provides promising preclinical data for the further development of BM-1197 in malignant lymphoma.

Proposal for a New TNM Stage based on the 7th and 8th American Joint Committee on Cancer pTNM Staging Classification for Gastric Cancer.

Background: The 8th edition of the American Joint Committee on Cancer (AJCC) staging system for gastric cancer incorporated several new changes. We aimed to assess the comparative prognostic values of the 7th and 8th AJCC pTNM staging systems in patients with gastric cancer (GC), and accordingly, to put forward a refined staging classification. Methods: The SEER database was queried to identify GC patients between 2004 and 2009. GC patients from Sun Yat-sen University Cancer Center (SYSUCC) were used as external validation data. The Kaplan-Meier method and Cox proportional hazards regression models were used to analyze cause-specific survival (CSS). The prognostic performance of different staging schemes was assessed using the concordance index (c-index), Akaike's information criterion (AIC), and likelihood ratio χ2 test. Results: In the SEER cohort, stage migration occurred in 8.74% of patients. Survival analysis showed that it was better to treat T4bN0M0 + T4aN2M0 as stage IIIB and T4bN3bM0 as stage IV. Based on this, we established a new staging system which exhibited a superior c-index (0.7501) to the 7th and 8th AJCC staging systems (0.7498 and 0.7500, respectively). The new staging system also outperformed the 7th and 8th AJCC staging systems in terms of AIC and the likelihood ratio χ2 test. The predictive superiority of the new staging system remained valid in the SYSUCC database. Conclusions: We demonstrated that some stage modifications in the 8th AJCC pathologic staging were unnecessary. Therefore we established a new staging system, which was superior to the 7th and 8th staging systems.

Frequency and clinicopathological features of metastasis to liver, lung, bone, and brain from gastric cancer: A SEER-based study.

The hematogenous metastatic pattern of gastric cancer (GC) was not fully explored. Here we analyzed the frequency and clinicopathological features of metastasis to liver, lung, bone, and brain from GC patients. Data queried for this analysis included GC patients from the Surveillance, Epidemiology, and End Results Program database from 2010 to 2014. All of statistical analyses were performed using the Intercooled Stata 13.0 (Stata Corporation, College Station, TX). All statistical tests were two-sided. Totally, there were 19 022 eligible patients for analysis. At the time of diagnosis, there were 7792 patients at stage IV, including 3218 (41.30%) patients with liver metastasis, 1126 (14.45%) with lung metastasis, 966 (12.40%) with bone metastasis and 151 (1.94%) with brain metastasis. GC patients with lung or liver metastasis have a higher risk of bone and brain metastasis than those without lung nor liver metastasis. Intestinal subtype had significantly higher rate of liver and lung metastasis, while diffuse type was more likely to have bone metastasis. Proximal stomach had significantly higher risk to develop metastasis than distal stomach. African-Americans had the highest risk of liver metastasis and Caucasian had the highest prone to develop lung and brain metastasis. The median survival for patients with liver, lung, bone, and brain metastasis was 4 months, 3 months, 4 months and 3 months, respectively. It is important to evaluate the status of bone and brain metastasis in GC patients with lung or liver metastasis. Knowledge of metastatic patterns is helpful for clinicians to design personalized pretreatment imaging evaluation for GC patients.

A novel small molecule inhibitor of MDM2-p53 (APG-115) enhances radiosensitivity of gastric adenocarcinoma.

BACKGROUND: Gastric cancer is the leading cause of cancer related death worldwide. Radiation alone or combined with chemotherapy plays important role in locally advanced and metastatic gastric adenocarcinoma. MDM2-p53 interaction and downstream signaling affect cellular response to DNA damage which leads to cell cycle arrest and apoptosis. Therefore, restoring p53 function by inhibiting its interaction with MDM2 is a promising therapeutic strategy for cancer. APG-115 is a novel small molecule inhibitor which blocks the interaction of MDM2 and p53. In this study, we investigated that the radiosensitivity of APG-115 in gastric adenocarcinoma in vitro and in vivo. METHODS: The role of APG-115 in six gastric cancer cells viability in vitro was determined by CCK-8 assay. The expression level of MDM2, p21, PUMA and BAX in AGS and MKN45 cell lines was measured via real-time PCR (RT-PCR). The function of treatment groups on cell cycle and cell apoptosis were detected through Flow Cytometry assay. Clonogenic assays were used to measure the radiosensitivity of APG-115 in p53 wild type gastric cancer cell lines. Western blot was conducted to detect the protein expressions of mdm2-p53 signal pathway. Xenograft models in nude mice were established to explore the radiosensitivity role of APG-115 in gastric cancer cells in vivo. RESULTS: We found that radiosensitization by APG-115 occurred in p53 wild-type gastric cancer cells. Increasing apoptosis and cell cycle arrest was observed after administration of APG-115 and radiation. Radiosensitivity of APG-115 was mainly dependent on MDM2-p53 signal pathway. In vivo, APG-115 combined with radiation decreased xenograft tumor growth much more significantly than either single treatment. Moreover, the number of proliferating cells (Ki-67) significantly decreased in combination group compared with single treatment group. CONCLUSIONS: In summary, we found that combination of MDM2-p53 inhibitor (APG-115) and radiotherapy can enhance antitumor effect both in vitro and in vivo. This is the first report on radiosensitivity of APG-115 which shed light on clinical trial of the combination therapy of radiation with APG-115 in gastric adenocarcinoma.

Correction to: Novel smac mimetic APG-1387 elicits ovarian cancer cell killing through TNF-alpha, Ripoptosome and autophagy mediated cell death pathway.

In the publication of this article [1], there was an error in Figs. 2, 3 and 6.