Clinical effectiveness and toxicity of second-line irinotecan in advanced gastric and gastroesophageal junction adenocarcinoma: a single-center observational study

Four Immune-Related Long Non-coding RNAs for Prognosis Prediction in Patients With Hepatocellular Carcinoma

BACKGROUND

Long non-coding RNA (LncRNA) plays an important role in the occurrence and development of hepatocellular carcinoma (HCC). This study aims to establish an immune-related LncRNA model for risk assessment and prognosis prediction in HCC patients.

METHODS

Hepatocellular carcinoma patient samples with complete clinical data and corresponding whole transcriptome expression were obtained from the Cancer Genome Atlas (TCGA). Immune-related genes were acquired from the Gene Set Enrichment Analysis (GSEA) website and matched with LncRNA in the TCGA to get immune-related LncRNA. Least Absolute Shrinkage and Selection Operator (LASSO) regression was used for screening the candidate LncRNAs and calculating the risk coefficient to establish the prognosis model. Patients were divided into a high-risk group and a low-risk group depending on the median risk score. The reliability of the prediction was evaluated in the validation cohort and the whole cohort. GSEA and principal component analysis were used for function evaluation.

RESULTS

A total of 319 samples met the screening criteria and were randomly distributed across the training cohort and the validation cohort. After comparison with the IMMUNE_RESPONSE gene set and the IMMUNE_SYSTEM_PROCESS gene set, a total of 3094 immune-related LncRNAs were screened. Ultimately, four immune-related LncRNAs were used to construct a formula using LASSO regression. According to the formula, the low-risk group showed a higher survival rate than the high-risk group in the validation cohort and the whole cohort. The receiver operating characteristic curves data demonstrated that the risk score was more specific than other traditional clinical characteristics in predicting the 5-year survival rate for HCC.

CONCLUSION

The four-immune-related-LncRNA model can be used for survival prediction in HCC and guide clinical therapy.

A methylation-based mRNA signature predicts survival in patients with gastric cancer

Background

Evidence suggests that altered DNA methylation plays a causative role in the occurrence, progression and prognosis of gastric cancer (GC). Thus, methylated-differentially expressed genes (MDEGs) could potentially serve as biomarkers and therapeutic targets in GC.

Methods

Four genomics profiling datasets were used to identify MDEGs. Gene Ontology enrichment and Kyoto Encyclopaedia of Genes and Genomes pathway enrichment analysis were used to explore the biological roles of MDEGs in GC. Univariate Cox and LASSO analysis were used to identify survival-related MDEGs and to construct a MDEGs-based signature. The prognostic performance was evaluated in two independent cohorts.

Results

We identified a total of 255 MDEGs, including 192 hypermethylation-low expression and 63 Hypomethylation-high expression genes. The univariate Cox regression analysis showed that 83 MDEGs were associated with overall survival. Further we constructed an eight-MDEGs signature that was independent predictive of prognosis in the training cohort. By applying the eight-MDEGs signature, patients in the training cohort could be categorized into high-risk or low-risk subgroup with significantly different overall survival (HR = 2.62, 95% CI 1.71–4.02, P < 0.0001). The prognostic value of the eight-MDEGs signature was confirmed in another independent GEO cohort (HR = 1.35, 95% CI 1.03–1.78, P = 0.0302) and TCGA-GC cohort (HR = 1.85, 95% CI 1.16–2.94, P = 0.0084). Multivariate cox regression analysis proved the eight-MDEGs signature was an independent prognostic factor for GC.

Conclusion

We have thus established an innovative eight-MDEGs signature that is predictive of overall survival and could be a potentially useful guide for personalized treatment of GC patients.

Irinotecan Induces Autophagy-Dependent Apoptosis and Positively Regulates ROS-Related JNK- and P38-MAPK Pathways in Gastric Cancer Cells

Background

Irinotecan (IRI) is considered an option for second-line treatment of advanced gastric cancer; however, acquired drug resistance currently limits its clinical application. Recently, many researchers have shown that autophagy plays a crucial role in the resistance of tumor cells to chemotherapy and radiotherapy. In this study, we investigated the relationship between autophagy and antitumor activity of IRI in gastric cancer cells.

Methods

We used MTT assay, flow cytometry and immunofluorescence staining to detect viability, apoptosis and autophagy in gastric cancer. Western blotting assay was used to determine the expression of LC3, Beclin-1, P62, cleaved PARP and Caspase 3. In vivo animal study was performed finally.

Results

We found that IRI treatment dose- and time-dependently inhibited growth and induced apoptosis in gastric cancer cells. Moreover, IRI treatment caused autophagy in these cells, whereas autophagy inhibitors—3-methyladenine (3-MA), chloroquine (CQ), and Beclin-1 small interfering RNA (siRNA)—suppressed cytotoxicity of IRI. A mechanistic analysis showed that IRI-induced autophagy and apoptosis were related to increased reactive oxygen species (ROS) accumulation and activation of the JNK- and p38-MAPK pathways. Further in vivo experiments revealed that IRI suppressed tumor growth, induced autophagy, and stimulated the JNK- and p38-MAPK pathways, whereas 3-MA attenuated these effects.

Conclusion

Taken together, these results indicate that IRI stimulates the ROS-related JNK- and p38-MAPK pathways to promote autophagy-dependent apoptosis. Thus, a combination of IRI with a pharmacological autophagy enhancer may be a promising therapeutic strategy against gastric cancer.

Downregulated Circular RNA hsa_circ_0000291 Suppresses Migration And Proliferation Of Gastric Cancer Via Targeting The miR-183/ITGB1 Axis

Background

Circular RNAs are implicated in a variety of cancers. This investigation found that hsa_circ_0000291 expression was upregulated in gastric cancer (GC) cell lines, yet its role in GC has not yet been reported.

Objective

To explore the effects of hsa_circ_0000291 on GC cell proliferation and invasion.

Materials and methods

In the current research, we used the gastric cancer cell lines MGC803 and MKN-28 to study hsa_circ_0000291 function. The relationship between hsa_circ_0000291, miR-183 and ITGB1 was analyzed by firefly luciferase analysis and Western blots, and qRT-PCR approaches were used for protein and gene expression analysis, respectively. Tumor growth and metastasis were determined in nude mice xenografts using MKN-28 cells, with or without hsa_circ_000r0291 downregulation.

Results

Our data showed that hsa_circ_0000291 was upregulated in GC cell lines, whereas hsa_circ_0000291 silencing suppressed cell metastasis and proliferation in in vivo and in vitro studies. Our results showed that the downregulation of hsa_circ_0000291 suppressed integrin beta 1 (ITGB1) expression via miR-183 “sponging,” which was validated by rescue experiments using the luciferase reporter assay. Our observations suggested that hsa_circ_0000291 silencing suppressed the aggressive, metastatic GC phenotype.

Conclusion

Taken together, hsa_circ_0000291 knockdown inhibited GC cell metastasis and growth by regulating the miR-183/ITGB1 axis. Importantly, this approach could provide a therapy target and potential biomarker for the diagnosis and treatment of GC.

The role of different adjuvant therapies in locally advanced gastric adenocarcinoma

Background and Purpose

Complete surgical resection remains the only curative treatment option in locally advanced gastric cancer (GC). Several studies were conducted to prevent local recurrence and to increase the chance of cure. The aim of this study was to summarize our experience in locally advanced GC patients treated with adjuvant chemoradiotherapy (CRT) and to evaluate overall survival (OS), disease-free survival (DFS), toxicity rate and compliance to treatment.

Materials and Methods

Locally advanced GC stage IB-III were included. Adjuvant CRT consisted of 45–50.4 Gy (1.8 Gy/day, 5 days/week) with concomitant Macdonald regimen (Mcd) or Epirubicin, Cisplatin and 5-Fluorouracil (ECF) scheme. Univariate and multivariate analysis of several prognostic factors for OS was conducted.

Results

Fourty-nine GC patients were treated: 24 received Mcd and 25 received ECF. Median follow up was 48 months. Acute grade 3–4 toxicity was observed in 6 patients. The 2-year and 5-year OS rates were 65.3% and 41.5%, respectively. The 2-year and 5-year DFS were 59.2% and 41.2%, respectively. No prognostic factors were significantly associated with OS.

Conclusions

Adjuvant CRT is a feasible strategy in locally advanced GC. It has an acceptable toxicity rate and it is able to increase both DFS and OS.