Antibody-drug conjugates in gastric cancer: from molecular landscape to clinical strategies.

Antibody-drug conjugates (ADCs) represent a crucial component of targeted therapies in gastric cancer, potentially altering traditional treatment paradigms. Many ADCs have entered rigorous clinical trials based on biological theories and preclinical experiments. Modality trials have also been conducted in combination with monoclonal antibody therapies, chemotherapies, immunotherapies, and other treatments to enhance the efficacy of drug coordination effects. However, ADCs exhibit limitations in treating gastric cancer, including resistance triggered by their structure or other factors. Ongoing intensive researches and preclinical experiments are yielding improvements, while enhancements in drug development processes and concomitant diagnostics during the therapeutic period actively boost ADC efficacy. The optimal treatment strategy for gastric cancer patients is continually evolving. This review summarizes the clinical progress of ADCs in treating gastric cancer, analyzes the mechanisms of ADC combination therapies, discusses resistance patterns, and offers a promising outlook for future applications in ADC drug development and companion diagnostics.

Burden and Trends of IBD in 5 Asian Countries From 1990 to 2019: A Comparison With the United States and the United Kingdom.

BACKGROUND: IBD is becoming a global health challenge, with substantial variations in incidence and death rates between Eastern and Western countries. OBJECTIVE: This study aimed to investigate the burden and trends of IBD in 5 Asian countries, the United States, and the United Kingdom. DESIGN: This was a cross-sectional study. SETTING: Data were obtained from Global Burden of Disease 2019 Study. PATIENTS: Patients with IBD were included. MAIN OUTCOME MEASURES: Incidence, death, and age-standardized rates of IBD were measured. RESULTS: The age-standardized incidence and rates of death from IBD gradually decreased worldwide from 1990 to 2019. The age-standardized incidence rate in the United States decreased from 1990 to 2000 and then increased gradually from 2000 to 2019; the age-standardized incidence rates in the United Kingdom, Mongolia, and China increased gradually from 1990 to 2019, whereas in the Democratic People's Republic of Korea, it decreased from 1990 to 1995 and increased gradually from 1995 to 2019. The age-standardized death rate in the Republic of Korea exhibited a rising trend until 1995, fell significantly up to 2015, and then stabilized from 2015 to 2019. The age-standardized death rate in the United States showed a rising trend until 2007, and then decreased gradually from 2007 to 2019, whereas the rate in the United Kingdom showed a rising trend until 2010 and decreased from 2010 to 2019. The age-standardized death rates in China, Mongolia, the Democratic People's Republic of Korea, and Japan decreased gradually from 1990 to 2019. The age-standardized incidence and death rates in the United States and United Kingdom in recent decades were higher than those in the 5 Asian countries. The peak age-standardized incidence rates in the 7 countries were among people of 20 to 60 years of age. The age-standardized death rates in all 7 countries exhibited rising trends with increasing age, with older individuals, particularly those aged ≥70 years, accounting for the most deaths. LIMITATIONS: Limitations of this study include data from different countries with different quality and accuracy. CONCLUSIONS: There have been large variations in the burdens and trends of IBD between 5 Asian countries, the United States, and the United Kingdom during the past 3 decades. These findings may help policymakers to make better public decisions and allocate appropriate resources. See Video Abstract at http://links.lww.com/DCR/B996 . CARGA Y TENDENCIAS DE LA ENFERMEDAD INFLAMATORIA INTESTINAL EN CINCO PASES ASITICOS DESDE HASTA UNA COMPARACIN CON LOS ESTADOS UNIDOS Y EL REINO UNIDO: ANTECEDENTES:La enfermedad inflamatoria intestinal se está convirtiendo en un desafío en la salud mundial, con variaciones sustanciales en las tasas de incidencia y mortalidad entre los países orientales y occidentales.OBJETIVO:Investigar la carga y las tendencias de la enfermedad inflamatoria intestinal en cinco países asiáticos, EE. UU. y el Reino Unido.DISEÑO:Estudio transversal.ESCENARIO:Estudio de carga global de morbilidad 2019.PACIENTES:Enfermedad inflamatoria intestinal.PRINCIPALES MEDIDAS DE RESULTADO:Incidencia, muerte y tasas estandarizadas por edad de enfermedad inflamatoria intestinal.RESULTADOS:Las tasas de incidencia y muerte estandarizadas por edad de la enfermedad inflamatoria intestinal disminuyeron gradualmente en todo el mundo desde 1990 hasta 2019. La tasa de incidencia estandarizada por edad en los EE. UU. disminuyó de 1990 a 2000 y luego aumentó gradualmente de 2000 a 2019, las tasas en el Reino Unido, Mongolia y China aumentaron gradualmente de 1990 a 2019, mientras que la tasa en la República Popular Democrática de Corea disminuyó de 1990 a 1995 y aumentó gradualmente de 1990 a 2019. La tasa de mortalidad estandarizada por edad en la República de Corea exhibió un tendencia ascendente hasta 1995, cayó significativamente hasta 2015 y luego se estabilizó de 2015 a 2019. La tasa de mortalidad estandarizada por edad en los EE. UU. mostró una tendencia ascendente hasta 2007 y luego disminuyó gradualmente de 2007 a 2019, mientras que la tasa en el Reino Unido mostró una tendencia ascendente hasta 2010 y disminuyó de 2010 a 2019. Las tasas de mortalidad estandarizadas por edad en China, Mongolia, la República Popular Democrática de Corea y Japón disminuyeron gradualmente de 1990 a 2019. La tasa de incidencia estandarizada por edad y mortalidad en los EE. UU. y el Reino Unido en la última década fueron más altas que las de los cinco países asiáticos. Las tasas máximas de incidencia estandarizadas por edad en los siete países se dieron entre personas de 20 a 60 años. Las tasas de mortalidad estandarizadas por edad en los siete países exhibieron tendencias crecientes con el aumento de la edad, y las personas mayores, en particular las de ≥70 años, representaron la mayoría de las muertes.LIMITACIONES:Datos de diferentes países con diferente calidad y precisión.CONCLUSIONES:Ha habido grandes variaciones en las cargas y tendencias de la enfermedad inflamatoria intestinal entre cinco países asiáticos, EE. UU. y el Reino Unido durante las últimas tres décadas. Estos hallazgos pueden ayudar a los formuladores de políticas a tomar mejores decisiones públicas y asignar los recursos apropiados. Consulte Video Resumen en http://links.lww.com/DCR/B996 . (Traducción- Dr. Francisco M. Abarca-Rendon ).

Prediction of tissue origin of adenocarcinomas in the esophagogastric junction by DNA methylation.

BACKGROUND: Prediction of tissue origin of esophagogastric junction (EGJ) adenocarcinomas can be important for therapeutic decision, but no molecular marker is available. Here, we aimed to develop such a marker taking advantage of tissue-specific profiles of DNA methylation. METHODS: DNA methylation profiles of gastric adenocarcinomas (GACs) were obtained by an Infinium HumanMethylation450 BeadChip array, and those of esophageal adenocarcinoma (EACs) were obtained from the TCGA database. DNA from formalin-fixed paraffin-embedded (FFPE) samples was analyzed by bisulfite pyrosequencing. RESULTS: In the screening set, 51 of 145,841 CpG sites in CpG islands were methylated at significantly higher levels in 30 GACs compared to those in 30 EACs. Among them, SLC46A3 and cg09177106 were unmethylated in all the 30 EACs. Predictive powers of these two markers were successfully confirmed in an independent validation set (18 GACs and 18 EACs) (SLC46A3, sensitivity = 77.8%, specificity = 100%; cg09177106, sensitivity = 83.3%, specificity = 94.4%), and could be applied to FFPE samples (37 GACs and 18 EACs) (SLC46A3, P = 0.0001; cg09177106, P = 0.0028). On the other hand, EAC-specific markers informative in the FFPE samples could not be isolated. Using these GAC-specific markers, nine of 46 (19.6%) TCGA EGJ adenocarcinomas were predicted to be GACs. CONCLUSIONS: Two GAC-specific markers, SLC46A3 and cg09177106, had a high specificity for identifying the tissue origin of EGJ adenocarcinoma.

The novel role and function of LINC01235 in metastasis of gastric cancer cells by inducing epithelial-mesenchymal transition.

LncRNAs play a vital role in the tumorigenesis of gastric cancer (GC). This study determined that LINC01235 expression has greater fold changes by analyzing TCGA RNA-Seq data. The qRT-PCR assay confirmed that LINC01235 is significantly over-expressed in GC cells and tissues. Additionally, the overall survival analysis showed that patients with a higher LINC01235 expression had a poorer prognosis than those with a lower LINC01235 expression. Univariate Cox regression analysis indicated that high LINC01235 expression is positively correlated with poor prognosis. Moreover, LINC01235 was an independent poor prognostic marker for GC in multivariate Cox analysis. Invitro assays suggested that LINC01235 knockdown suppresses GC cell migration and invasion. GSEA revealed that high LINC01235 expression is strongly enriched in the EMT pathway. Western blotting results revealed that LINC01235 silencing decreases the expression of EMT-induced proteins. In conclusion, LINC01235 can promote GC cell metastasis via EMT and function as a prognostic biomarker.

High flow nasal oxygen versus conventional oxygen therapy in gastrointestinal endoscopy with conscious sedation: Systematic review and meta-analysis with trial sequential analysis.

OBJECTIVES: Although conventional oxygen therapy (COT) is widely used, hypoxemia frequently occurs in gastrointestinal endoscopy with conscious sedation and can lead to life-threatening consequences. High flow nasal oxygen (HFNO) has been applied to improve oxygenation in clinical entities. However, its efficacy to prevent hypoxemia in gastrointestinal endoscopy with conscious sedation has not been evaluated. METHODS: We searched databases to identify randomized controlled trials that compared the efficacy of HFNO with COT in gastrointestinal endoscopy with conscious sedation. The primary outcome was hypoxemia. Meta-analyses with trial sequential analysis were performed using a random-effects model. RESULTS: Eight trials with 3212 patients were included. Compared with COT, HFNO significantly reduced the risk of hypoxemia (eight trials; 3212 patients; risk ratio 0.30; 95% confidence interval [CI] 0.13-0.70). Trial sequential analysis showed that the cumulative Z curve did not cross the monitoring or futility boundaries, nor reach the required information size line, indicating that more trials are needed to reach a definitive conclusion. Subgroup analyses indicated the superiority of HFNO over COT with respect to hypoxemia in patients at low risk and high risk. HFNO further improved the lowest oxygen saturation (four trials; 459 patients; mean difference 2.30, 95% CI 0.84-3.77). CONCLUSIONS: Compared with COT, HFNO can reduce the risk of hypoxemia and improve the lowest oxygen saturation in gastrointestinal endoscopy with conscious sedation. However, the results should be interpreted with caution due to substantial heterogeneity and limited evidence. Further studies are needed to verify the preliminary findings.

[Establishment and Preliminary Analysis of Lung Cancer Cell Line A549 with Stable MAP4 K4 Knockdown].

Objective: To analyze the effect of knocking down MAP4 K4 expression on the proliferation and migration of cancer cells, and to explore its underlining molecular mechanisms. Methods: A stable knockdown MAP4 K4 cell line was constructed and the subcellular localization of the cells was determined with immunofluorescence, cell proliferation assay and cell migration assay. In addition, the effects of down-regulated MAP4 K4 expression were analyzed by examining the difference between the proliferation and migration of cancer cells in the knockdown group and those of the control group. Results: MAP4 K4 was localized in focal adhesion and cell edges in A549 cells. Stable knockdown of MAP4 K4 expression induced cancer cells to grow in clusters and arrested the progression of the cell cycle and cell migration. Further analysis found that knocking down MAP4 K4 expression in A549 cells induced the accumulation of epithelial cell marker E-cadherin, and subsequently, the down-regulation of N-cadherin, a mesenchymal cell marker, thereby disrupting the "cadherin switch" and the epithelial-mesenchymal conversion. Then, the control group and the knockdown group both received the combined treatment of cisplatin at a final concentration of 5 µmol/L and paclitaxel at a final concentration of 20 nmol/L. The stably knocked down MAP4 K4 expressing cells showed significantly enhanced toxicity of chemotherapeutic drugs to cancer cells. Conclusion: The study shows that MAP4 K4 regulates the malignant phenotypes of cancer cells and chemoresistance by regulating "cadherin switch" to promote epithelial-mesenchymal transition in A549 cells.

DLX6-AS1/miR-204-5p/OCT1 positive feedback loop promotes tumor progression and epithelial-mesenchymal transition in gastric cancer.

BACKGROUND: Accumulating evidence indicates that long non-coding RNAs (lncRNAs) participate in progression of gastric cancer (GC). Nevertheless, the function and expression level of DLX6-AS1 in GC remain unknown. METHODS: We explored the sequencing data of DLX6-AS1 downloaded from The Cancer Genome Atlas. The expression of DLX6-AS1, miR-204-5p and OCT1 in 56 GC patients and GC cell lines was quantified by qRT-PCR and western blotting. Furthermore, we performed in vitro functional assays to assess proliferation, invasion and migration of GC cells by knockdown of DLX6-AS1. The expression level of epithelial-mesenchymal transition (EMT)-related genes was also determined by qRT-PCR and western blotting. Actin remodeling was detected by F-actin phalloidin staining. The luciferase reporter assay and chromatin immunoprecipitation assay was utilized to confirm the bioinformatic prediction. The function of the DLX6-AS1/miR-204-5p/OCT1 axis in GC proliferation was clarified by rescue assays. RESULTS: We first demonstrated that DLX6-AS1 was upregulated in GC tissues and cell lines and was associated with T3/T4 invasion, distant metastasis and poor clinical prognosis. Further functional analysis showed that downregulation of DLX6-AS1 inhibited GC cell proliferation, migration, invasion and EMT in vitro. Mechanistic investigation indicated that DLX6-AS1 acted as a cancer-promoting competing endogenous RNA (ceRNA) by binding miR-204-5p and upregulating OCT1. Moreover, the transcription factor OCT1 was confirmed to enhance DLX6-AS1 expression by targeting the promoter region. CONCLUSIONS: This study revealed that OCT1-induced DLX6-AS1 promoted GC progression and the EMT via the miR-204-5p/OCT1 axis, suggesting that this lncRNA might be a promising prognostic biomarker and therapeutic target for GC.

ZEB1-AS1 initiates a miRNA-mediated ceRNA network to facilitate gastric cancer progression.

BACKGROUND: Currently, cancer-related competing endogenous RNA (ceRNA) networks are attracting significant interest. As long noncoding RNA ZEB1-AS1 has been reported to function as an oncogene due to sponging microRNAs (miRNAs) in several cancers, we hypothesized that it could interact with specific miRNAs to form regulatory networks and facilitate the growth of gastric cancer (GC). METHODS: MiRNAs interacting with ZEB1-AS1 were screened for and selected by bioinformatics analysis. Overexpression or repression of ZEB1-AS1 was performed to determine whether it could regulate selected miRNAs. Quantitative real-time polymerase chain reactions (qPCR) validated the expression profiles of ZEB1-AS1 and miR-149-3p in GC cell lines and tissue. Statistical analysis determined the clinical significance of ZEB1-AS1 in relation to miR-149-3p. Cell counting, wound healing and transwell assays were performed to assess cell proliferation, migration and invasion. A luciferase reporter assay was utilized to confirm the putative miR-149-3p-binding sites in ZEB1-AS1. RESULTS: Briefly, bioinformatics analysis inferred that ZEB1-AS1 interacts with miR-204, miR-610, and miR-149. Gain- or loss-of function assays suggested that ZEB1-AS1 negatively regulates miR-149-3p, miR-204-5p and miR-610 in GC cells. Validated by qPCR, ZEB1-AS1 was up-regulated and miR-149-3p down-regulated in GC cells and tissue. Data analyses indicated that ZEB1-AS1 and miR-149-3p are associated with the independent diagnosis and prognosis of GC. Functional assays support the theory that miR-149-3p hinders GC proliferation, migration and invasion, whereas its overexpression abrogates the corresponding effects induced by ZEB1-AS1. Lastly, dissection of the molecular mechanisms involved indicated that ZEB1-AS1 can regulate GC partly via a ZEB1-AS1/miR-149-3p axis. CONCLUSIONS: ZEB1-AS1 can interact with specific miRNAs, forming a miRNA-mediated ceRNA network and promoting GC progress, partly through a ZEB1-AS1/miR-149-3p axis.

Correction to: ZEB1­AS1 initiates a miRNA­mediated ceRNA network to facilitate gastric cancer progression.

[This corrects the article DOI: 10.1186/s12935-019-0742-0.].

Downregulation of microRNA-376a in Gastric Cancer and Association with Poor Prognosis.

BACKGROUND/AIMS: MicroRNAs have a significant role in the tumorigenesis and progression of cancers, including gastric cancer (GC). Our study aimed to identify a novel biomarker to predict the prognosis of patients with GC. METHODS: The GC microarray dataset, GSE28700, was downloaded from the Gene Expression Omnibus (GEO) database and screened for differentially expressed miRNAs (DEMs). The downregulation of miR-376a expression was verified in GC cell lines and 82 paired GC tissues by performing RT-qPCR and the correlation between its expression and clinicopathological characteristics was also explored. The target genes of miR-376a were predicted using TargetScan7.1, miRDB, and DIANA website tools. A functional enrichment analysis was performed to explore the biological role of the common target genes. RESULTS: Bioinformatics analysis found that miR-376a was downregulated in GC tissues. Compared with the control group, RT-qPCR results showed that the expression of miR-376a in GC cell lines and tissues were also significantly decreased. The expression of miR-376a was statistically associated with T and N stage. Survival analysis with Kaplan-Meier showed that GC patients in the low expression group had a poorer prognosis than those in the high expression group (median survival of 26.4 and 46.9 months, respectively). Univariate and multivariate analysis demonstrated that low miR-376a expression was an independent prognostic marker for poor survival. Functional enrichment analysis indicated that the common targets genes were involved in cell-cell communication, VEGF and mTOR1-mediated signaling, and epithelial-to-mesenchymal transition (EMT). CONCLUSION: The results suggest that miR-376a could play an important role in the tumorigenesis and progression of GC and act as a novel therapeutic target and prognostic indicator in patients with GC.

miR-1236-3p inhibits invasion and metastasis in gastric cancer by targeting MTA2.

BACKGROUND: MicroRNAs deregulation are common in human tumor progression. miR-1236-3p has been reported to function as tumor suppressor microRNA in various malignancies. The aim of this study was to demonstrate the downregulated expression of miR-1236-3p in gastric cancer (GC) tissues and cell lines, and clarify its biological function in GC. METHODS: Real-time polymerase chain reaction was used to measure the mRNA level of miR-1236-3p in GC. Dual luciferase assay was used to demonstrate that MTA2 was one of the candidate target genes of miR-1236-3p. Western blots were utilized to detect the protein levels. Cell function assays were also performed to determine the function of miR-1236-3p in GC. RESULTS: miR-1236-3p expression, which was associated with lymph node metastasis, differentiation and clinical stage, was significantly reduced in GC tissues and cell lines. miR-1236-3p over-expression could inhibit GC cell proliferation, migration and invasion, and inhibition of miR-1236-3p expression had opposite effects. Furthermore, we demonstrated that MTA2 was a candidate target of miR-1236-3p, and miR-1236-3p over-expression significantly inhibited the process of epithelial-mesenchymal transition. We also found that miR-1236-3p could suppress the PI3K/Akt signaling pathway in GC cells. CONCLUSIONS: Our results suggest that miR-1236-3p functions as a tumor suppressor in GC and could be a promising therapeutic target for GC.

Up-regulation of CRKL by microRNA-335 methylation is associated with poor prognosis in gastric cancer.

BACKGROUND: MicroRNAs have been suggested to play a vital role in regulating carcinogenesis, tumor progression and invasion. MiR-335 is involved in suppressing metastasis and invasion in various human cancers. However, the mechanisms responsible for the aberrant expression of miR-335 in gastric cancer (GC) remain unknown. METHODS: Expression of miR-335 in four GC cell lines and 231 GC tissues was determined by real-time quantitative reverse transcriptase-polymerase chain reaction (qRT-PCR). DNA methylation status in the CpG islands upstream of miR-335 in GC cell lines and tissues was determined by methylation-specific PCR and bisulfite sequence-PCR. The effects of the demethylating agent 5-aza-2'-deoxycytidine on cell proliferation, apoptosis, cell cycle, migration, and invasion were investigated in GC cell lines. RESULTS: Cancer-specific methylation was detected in the upstream CpG-rich regions of miR-335, which dramatically silenced its transcriptional activity in GC cell lines and tissues. Low levels of miR-335 expression and high levels of miR-335 methylation in GC tissues were associated with poor clinical features and prognosis. Restoration of miR-335 expression in GC cells promoted cell apoptosis, inhibited tumor cell migration, invasion, and proliferation, and arrested the cell cycle at G0/G1 phase. Overexpression of miR-335 significantly reduced the activity of a luciferase reporter containing the 3' untranslated region of V-crk avian sarcoma virus CT10 oncogene homolog-like (CRKL). CONCLUSIONS: MiR-335 functions as a tumor suppressor and may be silenced by promoter hypermethylation. It plays a role in inhibiting tumor cell migration, invasion, and proliferation, arresting the cell cycle at G0/G1 phase, and promoting apoptosis in GC cells through targeting CRKL.

Type D personality is associated with delaying patients to medical assessment and poor quality of life among rectal cancer survivors.

OBJECTIVE: The aim of this research was to explore quality of life (QoL), mental health status, type D personality, symptom duration, and emergency admissions of Chinese rectal cancer patients as well as the relationship between these factors. METHODS: Type D personality was measured with the 14-item Type D Personality Scale (DS14). Mental health status was measured with the Hospital Anxiety and Depression Scale (HADS). The QoL outcomes were assessed longitudinally using the European Organization for Research and Treatment of Cancer QLQ-C30 and QLQ-CR38 questionnaires at the baseline and 6 months after diagnosis. RESULTS: Of the 852 survivors who responded (94 %), 187 (22 %) had a type D personality. The proportion of patients with duration of symptoms >1 month and being diagnosed after emergency admissions in type D group is significantly higher than that in non-type D group. At both of the time points, type D patients reported statistically significant lower scores on most of the functional scales, global health status/QoL scales, and worse symptom scores compared to patients without a type D personality. At the 6-month time point, a higher percentage of patients in the type D group demonstrated QoL deterioration. Clinically elevated levels of anxiety and depression were more prevalent in type D than in non-type D survivors. CONCLUSIONS: Type D personality was associated with poor QoL and mental health status among survivors of rectal cancer, even after adjustment for confounding background variables. Type D personality might be a general vulnerability factor to screen for subgroups at risk for longer symptom duration and emergency admissions in clinical practice.

The biological role of extracellular vesicles in gastric cancer metastasis.

Gastric cancer (GC) is a tumor characterized by high incidence and mortality, with metastasis being the primary cause of poor prognosis. Extracellular vesicles (EVs) are an important intercellular communication medium. They contain bioactive substances such as proteins, nucleic acids, and lipids. EVs play a crucial biological role in the process of GC metastasis. Through mechanisms such as remodeling the tumor microenvironment (TME), immune suppression, promoting angiogenesis, and facilitating epithelial-mesenchymal transition (EMT) and mesothelial-mesenchymal transition (MMT), EVs promote invasion and metastasis in GC. Further exploration of the biological roles of EVs will contribute to our understanding of the mechanisms underlying GC metastasis and may provide novel targets and strategies for the diagnosis and treatment of GC. In this review, we summarize the mechanisms by which EVs influence GC metastasis from four aspects: remodeling the TME, modulating the immune system, influencing angiogenesis, and modulating the processes of EMT and MMT. Finally, we briefly summarized the organotropism of GC metastasis as well as the potential and limitations of EVs in GC.

Ubiquitin-specific proteases: From biological functions to potential therapeutic applications in gastric cancer.

Deubiquitination, a post-translational modification regulated by deubiquitinases, is essential for cancer initiation and progression. Ubiquitin-specific proteases (USPs) are essential elements of the deubiquitinase family, and are overexpressed in gastric cancer (GC). Through the regulation of several signaling pathways, such as Wnt/ß-Catenin and nuclear factor-κB signaling, and the promotion of the expression of deubiquitination- and stabilization-associated proteins, USPs promote the proliferation, metastasis, invasion, and epithelial-mesenchymal transition of GC. In addition, the expression of USPs is closely related to clinicopathological features, patient prognosis, and chemotherapy resistance. USPs therefore could be used as prognostic biomarkers. USP targeting small molecule inhibitors have demonstrated strong anticancer activity. However, they have not yet been tested in the clinic. This article provides an overview of the latest fundamental research on USPs in GC, aiming to enhance the understanding of how USPs contribute to GC progression, and identifying possible targets for GC treatment to improve patient survival.

Hospital volume-mortality association after esophagectomy for cancer: a systematic review and meta-analysis.

BACKGROUND: Postoperative mortality plays an important role in evaluating the surgical safety of esophagectomy. Although postoperative mortality after esophagectomy is partly influenced by the yearly hospital surgical case volume (hospital volume), this association remains unclear. METHODS: Studies assessing the association between hospital volume and postoperative mortality in patients who underwent esophagectomy for esophageal cancer were searched for eligibility. Odds ratios were pooled for the highest versus lowest categories of hospital volume using a random effects model. The dose-response association between hospital volume and the risk of postoperative mortality was analyzed. The study protocol was registered with PROSPERO. RESULTS: Fifty-six studies including 385 469 participants were included. A higher-volume hospital significantly reduced the risk of postesophagectomy mortality by 53% compared with their lower-volume counterparts (odds ratio, 0.47; 95% CI: 0.42-0.53). Similar results were found in subgroup analyses. Volume-outcome analysis suggested that postesophagectomy mortality rates remained roughly stable after the hospital volume reached a plateau of 45 esophagectomies per year. CONCLUSIONS: Higher-volume hospitals had significantly lower postesophagectomy mortality rates in patients with esophageal cancer, with a threshold of 45 esophagectomies per year for a high-volume hospital. This remarkable negative correlation showed the benefit of a better safety in centralization of esophagectomy to a high-volume hospital.

Methylation synthetic lethality: Exploiting selective drug targets for cancer therapy.

In cancer, synthetic lethality refers to the drug-induced inactivation of one gene and the inhibition of another in cancer cells by a drug, resulting in the death of only cancer cells; however, this effect is not present in normal cells, leading to targeted killing of cancer cells. Recent intensive epigenetic research has revealed that aberrant epigenetic changes are more frequently observed than gene mutations in certain cancers. Recently, numerous studies have reported various methylation synthetic lethal combinations involving DNA damage repair genes, metabolic pathway genes, and paralogs with significant results in cellular models, some of which have already entered clinical trials with promising results. This review systematically introduces the advantages of methylation synthetic lethality and describes the lethal mechanisms of methylation synthetic lethal combinations that have recently demonstrated success in cellular models. Furthermore, we discuss the future opportunities and challenges of methylation synthetic lethality in targeted anticancer therapies.

Neoadjuvant chemotherapy for nonmetastatic esophago-gastric adenocarcinomas: a systematic review and meta-analysis.

OBJECTIVE: A systematic review and meta-analysis was performed to investigate the efficacy of neoadjuvant chemotherapy for nonmetastatic esophago-gastric adenocarcinomas. METHODS: Electronic databases were searched systematically from January 1980 to July 2012 and a total of 2,587 patients from 17 randomized controlled trials were subjected to meta-analysis. The odds ratios (ORs) for overall survival (OS) and progression-free survival (PFS) were calculated. RESULTS: Seventeen randomized controlled trials were obtained and various comparisons of treatment approaches were performed. Randomized controlled trials detected no differences in these comparisons: R0 resection for neoadjuvant chemotherapy versus none; Preoperative chemotherapy versus surgery alone: 3-year OS, 5-year OS, 5-year OS in Europe, 3-year PFS; Preoperative chemotherapy plus postoperative chemotherapy versus postoperative chemotherapy: 1-year OS, 5-year OS; Preoperative chemotherapy versus preoperative chemoradiotherapy: 3-year OS. Randomized controlled trials detected significant differences in these comparisons: Preoperative chemotherapy plus postoperative chemotherapy versus surgery alone: 3-year and 5-year PFS, 5-year OS; Subgroup analysis examining preoperative chemotherapy versus surgery alone: 5-year OS in Asia; Preoperative chemotherapy versus postoperative chemotherapy: 1-year OS. CONCLUSION: The current limited evidence suggests that preoperative chemotherapy can be applied to patients with nonmetastatic esophago-gastric adenocarcinomas (specifically, advanced esophago-gastric cancer). However, the results should be interpreted with caution because of the statistically low power and the heterogeneity among study designs; therefore, our results need validations in future studies.

Association of hospital volume and long-term survival after esophagectomy: A systematic review and meta-analysis.

Background: It remains controversial whether esophageal cancer patients may benefit from esophagectomy in specialized high-volume hospitals. Here, the effect of hospital volume on overall survival (OS) of esophageal cancer patients post esophagectomy was assessed. Methods: PubMed, Embase, and Cochrane Library were systematically searched for relevant published articles between January 1990 and May 2022. The primary outcome was OS after esophagectomy in high- vs. low-volume hospitals. Random effect models were applied for all meta-analyses. Subgroup analysis were performed based on volume grouping, sample size, study country, year of publication, follow-up or study quality. Sensitivity analyses were conducted using the leave-one-out method. The Newcastle-Ottawa Scale was used to assess the study quality. This study followed the Preferred Reporting Items for Systematic Reviews and Meta-analysis guidance, and was registered (identifier: INPLASY202270023). Results: A total of twenty-four studies with 113,014 patients were finally included in the meta-analysis. A significant improvement in OS after esophagectomy was observed in high-volume hospitals as compared to that in their low-volume counterparts (HR: 0.77; 95% CI: 0.71-0.84, P < 0.01). Next, we conducted subgroup analysis based on volume grouping category, consistent results were found that high-volume hospitals significantly improved OS after esophagectomy than their low-volume counterparts. Subgroup analysis and sensitivity analyses further confirmed that all the results were robust. Conclusions: Esophageal cancer should be centralized in high-volume hospitals.