Prognostic impact of Ki-67 in patients with gastric cancer-the importance of depth of invasion and histologic differentiation

The Prognostic Importance of Ki-67 in Gastrointestinal Carcinomas: A Meta-analysis and Multi-omics Approach

PURPOSE

This study aimed to determine if Ki-67, a commonly used marker to measure tumor proliferation, is a reliable prognostic factor in various types of gastrointestinal (GI) cancers based on current high-quality multivariable evidence.

METHODS

A comprehensive search was conducted in PubMed, Embase, Scopus, and ISI Web of Science databases to investigate the association between Ki-67 positivity and overall survival (OS) and disease/recurrence-free survival (DFS/RFS) in GI cancers. Heterogeneity was assessed using Chi-square-based Q and I2 analyses and publication bias using funnel plots and Egger's analysis. In addition, Ki-67 levels in different GI cancers were examined by different platforms. The prognostic capability of Ki-67, gene ontology (GO), and pathway enrichment analysis were obtained from GEPIA2 and STRING.

RESULTS

Totally, 61 studies, involving 13,034 patients, were deemed eligible for our evaluation. The combined hazard ratios (HRs) demonstrated the prediction ability of overexpressed Ki-67 for a worse OS (HR: 1.67, P < 0.001; HR: 1.37, P = 0.021) and DFS/RFS (HR: 2.06, P < 0.001) in hepatocellular and pancreatic malignancies, respectively, as confirmed by multi-omics databases. However, similar correlation was not found in esophageal, gastric, and colorectal cancers. Furthermore, most of the associations were identified to be robust based on different subcategories and publication bias assessment. Finally, enriched Ki-67-related genes were found to be involved in various important signaling pathways, such as cell cycle, P53 signaling network, and DNA damage responses.

CONCLUSION

This study supports that Ki-67 can serve as an independent prognostic biomarker for pancreatic and hepatocellular malignancies in clinical settings.

Nomogram development and validation to predict Ki-67 expression of hepatocellular carcinoma derived from Gd-EOB-DTPA-enhanced MRI combined with T1 mapping

Objective

As an important biomarker to reflect tumor cell proliferation and tumor aggressiveness, Ki-67 is closely related to the high early recurrence rate and poor prognosis, and pretreatment evaluation of Ki-67 expression possibly provides a more accurate prognosis assessment and more better treatment plan. We aimed to develop a nomogram based on gadolinium ethoxybenzyl diethylenetriamine pentaacetic acid (Gd-EOB-DTPA)-enhanced magnetic resonance imaging (MRI) combined with T1 mapping to predict Ki-67 expression in hepatocellular carcinoma (HCC).

Methods

This two-center study retrospectively enrolled 148 consecutive patients who underwent preoperative Gd-EOB-DTPA-enhanced MRI T1 mapping and surgically confirmed HCC from July 2019 to December 2020. The correlation between quantitative parameters from T1 mapping, ADC, and Ki-67 was explored. Three cohorts were constructed: a training cohort (n = 73) and an internal validation cohort (n = 31) from Shunde Hospital of Southern Medical University, and an external validation cohort (n = 44) from the Sixth Affiliated Hospital, South China University of Technology. The clinical variables and MRI qualitative and quantitative parameters associational with Ki-67 expression were analyzed by univariate and multivariate logistic regression analyses. A nomogram was developed based on these associated with Ki-67 expression in the training cohort and validated in the internal and external validation cohorts.

Results

T1rt-Pre and T1rt-20min were strongly positively correlated with Ki-67 (r = 0.627, r = 0.607, P < 0.001); the apparent diffusion coefficient value was moderately negatively correlated with Ki-67 (r = -0.401, P < 0.001). Predictors of Ki-67 expression included in the nomogram were peritumoral enhancement, peritumoral hypointensity, T1rt-20min, and tumor margin, while arterial phase hyperenhancement (APHE) was not a significant predictor even included in the regression model. The nomograms achieved good concordance indices in predicting Ki-67 expression in the training and two validation cohorts (0.919, 0.925, 0.850), respectively.

Conclusions

T1rt-Pre and T1rt-20min had a strong positive correlation with the Ki-67 expression in HCC, and Gd-EOB-DTPA enhanced MRI combined with T1 mapping-based nomogram effectively predicts high Ki-67 expression in HCC.

Potential stem cell-Conditioned medium and their derived exosomes versus omeprazole in treatment of experimental model of gastric ulcer

Gastric ulcer is a common frequent clinical problem affecting all age and gender. This work aims to compare between the therapeutic effects of stem cell derived exosomes, stem cells conditioned medium and omeprazole on the healing of gastric ulcer model. Fifty rats were, assigned into 5 groups; control, gastric ulcer, omeprazole-treated, conditioned medium- treated, and exosomes-treated groups. Gastric ulcer was induced by aspirin dissolved in 1% carboxymethyl cellulose at a daily dose of 200 mg/kg for 5 consecutive days. Stomach specimens were obtained for histological, biochemical, and immunohistochemical assessments. The gastric ulcer group revealed widening of the fundic glands lumen containing, exfoliated dead cells. There was a remarkable distortion of the normal histological structure of the gastric mucosa with surface lining epithelial cell sloughing, vascular congestion and inflammatory cell infiltration. Both exosomes and conditioned medium treatments ameliorated almost all of the histopathological changes. Interestingly, the healing effect of exosomes was greater because it restored the histological architecture of gastric mucosa to nearly normal. In conclusion, this work may pave the future for using stem cell derived exosomes as a more convenient and effective adjuvant therapy in gastric ulcer.

Cyclin D1 Serves as a Poor Prognostic Biomarker in Stage I Gastric Cancer

TNM stage still serves as the best prognostic marker in gastric cancer (GC). The next step is to find prognostic biomarkers that detect subgroups with different prognoses in the same TNM stage. In this study, the expression levels of epidermal growth factor receptor (EGFR) and cyclin D1 were assessed in 96 tissue samples, including non-tumorous tissue, adenoma, and carcinoma. Then, the prognostic impact of EGFR and cyclin D1 was retrospectively investigated in 316 patients who underwent R0 resection for GC. EGFR positivity increased as gastric tissue became malignant, and cyclin D1 positivity was increased in all the tumorous tissues. However, there was no survival difference caused by the EGFR positivity, while the cyclin D1-postive group had worse overall survival (OS) than the cyclin D1-negative group in stage I GC (10-year survival rate (10-YSR): 62.8% vs. 86.5%, p = 0.010). In subgroup analyses for the propensity score-matched (PSM) cohort, there were also significant differences in the OS according to the cyclin D1 positivity in stage I GC but not in stage II and III GC. Upon multivariate analysis, cyclin D1 positivity was an independent prognostic factor in stage I GC. In conclusion, cyclin D1 may be a useful biomarker for predicting prognosis in stage I GC.

Immunohistochemical expression of FOXP3 in gastric carcinoma; its relation to Ki-67 proliferation marker, HER2/neu expression, and other clinicopathological parameters

Gastric cancer is common cancer in the world. Contradictory results regarding FOXP3 expression in gastric carcinoma were detected and the role of Ki-67 in prognosis is not completely understood. Furthermore, due to increasing use of anti-HER2 drug trastuzumab for gastric cancer, assessment of HER2 expression becomes important. This study tried to assess the FOXP3 expression in gastric carcinoma and to study the relation between its expression and Ki-67 and HER2/neu expression and relation between their expression and other clinicopathological variables. This retrospective study was carried out on 60 gastric adenocarcinoma cases. Tissue microarrays and immunohistochemical staining for FOXP3, Ki-67 and HER2/neu were done and then assessed and scored. HER2/neu expression showed significant relation to Lauren histological type and lymph node status. High Ki-67 index was related significantly to patients' age, lympho-vascular tumor emboli, peri-neural invasion, tumor grade, lymph node status, and cancer stage. There was significant relation between high FOXP3 expression and patients' age, lympho-vascular tumor emboli, peri-neural invasion, tumor grade, lymph node status, and cancer stage. Direct positive significant relationships between HER2/neu, Ki-67, and FOXP3 expression were noticed. Finally, high FOXP3 expression, positive HER2/neu, and high Ki-67 nuclear proliferation index may be an indication of the aggressiveness of gastric carcinoma.

HER-2 positivity is a high risk of recurrence of stage I gastric cancer

BACKGROUND/AIMS

The treatment of gastric cancer remains unsatisfactory. We aimed to investigate the prognostic value of immunohistochemical staining in gastric cancer.

METHODS

We analyzed 505 (279 early staged, 226 advanced-staged) gastric cancer tissues from patients who underwent radical gastric resection between January 2014 and December 2016. Available surgical specimens immunohistochemically stained for p53, epidermal growth factor receptor (EGFR), human EGFR 2 (HER-2), E-cadherin, and Ki-67 were reviewed. We evaluated the association between positivity to various biomarkers and disease recurrence, disease-free survival, lymph node metastasis, and microscopic lymphovascular invasion.

RESULTS

The median follow-up duration was 32.5 months (range, 7 to 70). Advanced gastric cancer cases showed high Ki-67 expression; other cases showed unremarkable expression. Concerning disease recurrence, lymphatic invasion, and disease-free interval, all biomarkers had no prognostic effects. HER-2-positive stage I gastric cancer tended to occur in old patients and in the upper one-third of the stomach (p = 0.01). HER-2 positivity was significantly correlated with disease recurrence (p = 0.01), lymphatic invasion (p = 0.03), and vascular invasion (p = 0.03) in stage I cases.

CONCLUSION

Only HER-2 was associated with the recurrence of stage I gastric cancer. HER-2-positive stage I gastric cancer requires additional therapy despite curative resection.

TP53 Co-Mutational Features and NGS-Calibrated Immunohistochemistry Threshold in Gastric Cancer

Purpose

TP53 is the most frequently mutated gene in gastric cancer and it can be potentially used for gastric cancer diagnosis and screening. However, standardized clinical approaches that could accurately and cost-effectively detect TP53 mutations in gastric cancer are largely lagged behind.

Patients and Methods

We conducted next-generation sequencing (NGS) analysis of 425 cancer-related genes in 42 gastric cancer patients in our cohort. A 1313-patient cohort derived from the cBioPortal database was used for validation. We performed immunohistochemistry (IHC) staining with four commonly used p53 antibodies, and the NGS results were used as the gold standard to optimize the IHC threshold for each antibody.

Results

By NGS analysis, we found that around 80% of gastric cancer patients in our cohort harbored TP53 alterations. Genetic alterations of BRCA1/2 or KMT2B were mostly exclusive with TP53 mutations, so were the MSI status or low grade of tumors. These results were further validated using the data from cBioPortal. We then used the NGS-derived TP53 status to optimize four commonly used IHC antibodies for detecting TP53 mutations. We showed that all antibodies could achieve more than 93% accuracy when proper IHC positivity thresholds were used, especially for the SP5 antibody that could reach 100% sensitivity and specificity with the 20% threshold.

Conclusion

Our results indicated that exclusivity between TP53 and BRCA mutations could be potentially used as a cost-effective way to predict BRCA status. Also, setting proper IHC thresholds for each specific antibody is critical to accurately detect TP53 mutations and facilitate disease diagnosis.

Analysis of Endoscopy Findings to Identify Early Gastric Cancers with Tumor Budding: A Retrospective Study

BACKGROUND

No reliable method has been reported for determining tumor budding with frozen sections during surgical procedures. This study investigated endoscopic features predictive of tumor budding in early gastric cancers (EGC).

METHODS

This retrospective study evaluated data from 137 patients diagnosed with EGC who underwent endoscopy, followed by endoscopic submucosal dissection (ESD); 71 patients underwent a second gastrectomy. Based on pathological analyses, lesions were categorized as being positive (n = 80) or negative for tumor budding (n = 57). Endoscopic features were analyzed using multivariable logistic regression. Patient survival rates were analyzed with Kaplan-Meier method and log-rank test.

RESULTS

Mean age of our study population was 66 years (range, 31-86 years). The tumor budding-positive cohort (73.3 ± 5.9 years) was significantly older than the tumor budding-negative cohort (56.7 ± 7.6 years) (p < 0.001). Endoscopic features significantly different between tumor budding-positive and budding-negative groups included tumor size (p = 0.003), remarkable redness (p = 0.015), and margin elevation (p < 0.001). Tumor size (odds ratio (OR): 1.561; 95% confidence interval (CI): 0.984, 2.285; p = 0.047) and margin elevation (OR: 2.141; 95% CI: 1.147, 5.117; p = 0.003) were independent predictors of tumor budding. Margin elevation was found in 19.3% of tumor budding-negative and 53.8% of budding-positive cases. In the tumor budding-positive group, ESD and second gastrectomy were associated with disease-free survival.

CONCLUSIONS

Margin elevation and large tumor size (> 29 mm) of EGCs on endoscopy are promising imaging biomarkers for predicting tumor budding in EGCs. ESD and a second gastrectomy can be better for tumor budding-positive patients with EGCs.

Identification of hub genes and discovery of promising compounds in gastric cancer based on bioinformatics analysis

Aim: To explore the mechanism of gastric carcinogenesis by mining potential hub genes and to search for promising small-molecular compounds for gastric cancer (GC). Materials & methods: The microarray datasets were downloaded from Gene Expression Omnibus database and the genes and compounds were analyzed by bioinformatics-related tools and software. Results: Six hub genes (MKI67, PLK1, COL1A1, TPX2, COL1A2 and SPP1) related to the prognosis of GC were confirmed to be upregulated in GC and their high expression was correlated with poor overall survival rate in GC patients. In addition, eight candidate compounds with potential anti-GC activity were identified, among which resveratrol was closely correlated with six hub genes. Conclusion: Six hub genes identified in the present study may contribute to a more comprehensive understanding of the mechanism of gastric carcinogenesis and the predicted potential of resveratrol may provide valuable clues for the future development of targeted anti-GC inhibitors.

Ribosomal DNA copy number is associated with P53 status and levels of heavy metals in gastrectomy specimens from gastric cancer patients

The ribosomal DNA (rDNA) can act as a sensor and responder of cancer-associated stress. Here we investigated rDNA copy number in gastric cancers and its association with existing biomarkers and metals exposure. This study was performed on paired tumor and adjacent normal tissues obtained from 65 gastric cancer patients who underwent gastrectomy. Immunohistochemistry was used to assess HER-2, E-cadherin, EGFR, CK (pan), CK20, CK7, TopoⅡ, CAM5.2, P53, and Ki-67 expression. Inductively coupled plasma mass spectrometry (ICP-MS) was used to detect the concentrations of 17 metals in gastric tissues. rDNA copy number was detected by qPCR in genomic DNA isolated from tissue samples. Associations between the expression of existing markers, metal concentrations, and rDNA copy number were evaluated. Within patients with gastric cancer, the copy number of the 45S rDNA components (18S, 5.8S, 28S) and the 5S rDNA in tumor tissues were significantly higher than those in adjacent normal tissues, whereas mitochondrial DNA (mtDNA) copy number was significantly lower in tumor tissues than that in adjacent normal tissues. Further analysis revealed that the increase in 18S, 5.8S, and 28S rDNA copy number in tumor tissues was diminished in the context of EGFR and P53 loss. Moreover, analysis of metals revealed particularly high concentrations of As, Cd, Cr, Cu and Fe in the gastric tissues of these patients. Intriguingly, rDNA copy number variation across individuals was correlated with the concentrations of some metals. The rDNA was amplified in tumor tissues of gastric cancer patients, and its amplification may be associated with metals exposure. The expression of EGFR and P53 may influence rDNA copy number, with diminished amplification of the rDNA in cancers that were negative for these biomarkers. Our observation further our understanding of rDNA copy number in gastric cancer and its potential as a simple and useful marker in gastric cancer monitoring.

STAT3 Inhibition for Gastroenteropancreatic Neuroendocrine Tumors: Potential for a New Therapeutic Target?

BACKGROUND

Gastroenteropancreatic neuroendocrine tumors (GEP-NETs) are highly vascular neoplasms treated similarly, irrespective of tumor location. The expression of pro-angiogenic factors (STAT3, VEGF, and HIF-1α) and their association with adverse pathologic factors and disease recurrence following resection remains unclear.

METHODS

All patients with non-metastatic GEP-NETs who underwent curative-intent resection from 2000 to 2013 were included. Immunohistochemistry was performed for pro-angiogenic factors, Ki-67 index, and CD31 using tissue microarrays made in triplicate by a pathologist blinded to other clinicopathologic variables. Primary outcome was a 3-year recurrence-free survival (3-yrRFS); secondary outcomes were correlation of pro-angiogenic factors with Ki-67 index, adverse pathologic factors, and CD31 expression, a marker of microvascular density.

RESULTS

Of 144 GEP-NETs resected, STAT3 expression was high in 12 (8%) and low in 132 (92%) pts. High STAT3 expression was associated with worse 3-yrRFS compared to low expression (55% vs 84%; p = 0.003). High VEGF expression had a 3-yrRFS of 76% vs 82% for low expression (p = 0.09). HIF-1α expression was not associated with RFS. Ki-67 ≥ 3% was associated with worse 3-yrRFS (≥ 3%: 51% vs < 3%: 84%; p < 0.001), as was the presence of increased microvascular density (CD31 > median: 75% vs CD31 < median: 86%; p = 0.04). High STAT3 expressing tumors were more likely to have a Ki-67 ≥ 3% (42% vs 7%; p < 0.001). LVI was present in 82% of high STAT3 tumors compared to only 50% with low STAT3 (p = 0.058). CD31 expression was similar between groups (58% vs 49%; p = 0.5).

CONCLUSIONS

In resected GEP-NETs, high STAT3 expression is associated with an increased Ki-67 index, presence of lymphovascular invasion and worse 3-yr RFS. STAT3 may be a novel therapeutic target for patients undergoing resection of high-risk tumors.

Development of a novel gene signature in patients without Helicobacter pylori infection gastric cancer

Gastric cancer (GC) is one of the most fatal common cancers in worldwide. Helicobacter pylori (H. pylori) infection is closely related to the development of GC, although the mechanism is still unclear. In our study, we aim to develop a robust messenger RNA (mRNA) signature associated with H. pylori (-) GC that can sensitively and efficiently predict the prognostic. The RNA-seq expression profile and corresponding clinical data of 598 gastric cancer samples and 63 normal samples obtained from The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus database. Using gene set enrichment analysis H. pylori (+) GC and H. pylori (-) GC patients and normal samples to select certain genes for further analysis. Using univariate and multivariate Cox regression model to establish a gene signature for predicting the overall survival (OS). Finally, we identified G2/M related seven-mRNA signature (TGFB1, EGF, MKI67, ILF3, INCENP, TNPO2, and CHAF1A) closely related to the prognosis of patients with H. pylori (-) GC. The seven-mRNA signature was identified to act as an independent prognostic biomarker by stratified analysis and multivariate Cox regression analysis. It was also validated on two test groups from TCGA and GSE15460 and shown that patients with high-risk scores based on the expression of the seven mRNAs had significantly shorter survival times compared to patients with low-risk scores (P < .0001). In this study, we developed a seven-mRNA signature related to G2/M checkpoint from H. pylori (-) GCs that as an independent biomarker potentially with a good performance in predicting OS and might be valuable for the clinical management for patients with GC.

Gastric foveolar-type adenomas endoscopically showing a raspberry-like appearance in the Helicobacter pylori -uninfected stomach

Background and study aims  Foveolar-type adenoma is described as a very rare tumor that occurs in individuals without Helicobacter pylori (HP) infection and diagnosed as adenocarcinoma in the Japanese Classification of Gastric Carcinoma (JCGC). However, we have frequently encountered patients with foveolar-type adenoma that endoscopically resembles a hyperplastic polyp, suggesting that it has just been overlooked to date. Here, we analyzed clinicopathological characteristics of a special subtype of foveolar-type adenoma showing specific endoscopic findings. Patients and methods  From a total of 212 patients with gastric cancer resected during a 22-month period, we enrolled 14 (6.6 %) diagnosed with foveolar-type adenoma (adenocarcinoma in JCGC). HP infection status was determined by eradication history, HP serum IgG antibody level, urea breath test, and endoscopic and histological findings. All lesions were observed using white-light endoscopy and narrow-band imaging with magnification endoscopy (NBIME). Endoscopically resected lesions were histologically examined. Results  None of 14 patients had a current or past history of HP infection. All lesions were visualized on non-atrophic gastric mucosa as small reddish protrusions with fine granular surface, showing a raspberry-like appearance. NBIME showed papillary or gyrus-like microstructures with irregular capillary. Lesions were histologically diagnosed as foveolar-type adenoma showing MUC5AC-positive gastric mucin phenotype. Ki-67 was overexpressed (median labeling index 69.9 %, range 28.4 - 92.1 %), though all lesions were an intraepithelial tumor without stromal invasion. p53 over-staining was not seen in any. Conclusions  Raspberry-like lesions on non-atrophic gastric mucosa in HP-uninfected individuals should be evaluated for the possibility of a special subtype of foveolar-type adenoma.

Prevalence of Her3 in gastric cancer and its association with molecular prognostic markers: a Saudi cohort based study

Her 3 is a member of epidermal growth factor receptors. Mutated, oncogenic Her3 is reported in gastric and colonic cancers with emerging evidence that Her3 can be a potential target for molecular therapies. There is a paucity of studies regarding Her3 and its prognostic implications in gastric cancer in our region. In this study, we evaluated prevalence of Her3 in gastric cancer, in a Saudi cohort of cases, along with its association with prognostic markers p53 and Ki-67. The study was conducted in Department of Pathology of King Fahd Hospital of Imam Abdulrahman Bin Faisal University, Dammam, KSA. Fifty cases of gastric carcinoma were selected from the pathology files that fulfilled the inclusion criteria. Clinico-pathological parameters, Laurens histological classification, and immunohistochemical staining for Her3, p53, and Ki-67 were done. Her 3 positive cases were also evaluated for Her-2neu co-expression. Her3 positivity was seen in 16% (n = 8) out of a total of 50 cases. The median age of presentation was 44 years. Within Her3 positive cases, a female preponderance of 63% (n = 5), presence of high grade tumors in 75% (n = 6), diffuse gastric carcinoma in 63% (n = 5), diffuse to focal p53 positivity in 63% (n = 5), and a high to moderate Ki-67 proliferation index in 75% (n = 6) of cases was seen. Her3 expression was independent of Her-2neu status. Her3 prevalence of 16% with a median age of 44 years at presentation was less than in other reported studies, highlighting the concept of ethnic and regional variation in tumor characteristics. Her3 association with diffuse gastric carcinoma, high grade tumors, diffuse to focal p53 positivity and high to moderate Ki-67 proliferation index points towards a more aggressive clinical behavior.

Computed tomographic characteristics of gastric schwannoma

Objective

This study aimed to characterize the computed tomographic (CT) features of gastric schwannoma (GS).

Methods

We retrospectively reviewed CT images of 19 cases of histologically proven GS between January 2010 and December 2015. Tumor location, size, contour, margin, growth pattern, and degree and pattern of enhancement, perigastric lymph nodes, ulceration, necrosis, and calcification were evaluated.

Results

GS was located in the gastric body (73.7%), gastric antrum (15.8%), and gastric fundus (10.5%), with a mean maximum diameter of 4.5 ± 1.8 cm. All tumors presented as oval, well-defined solid masses, with exophytic (36.8%), endoluminal (15.8%), or mixed (47.4%) growth patterns. Ulcers (57.9%) and perigastric lymph nodes (47.4%) were observed. Moderate enhancement (87.5%) was observed in the portal phase. Eighteen (94.7%) cases showed homogeneous enhancement.

Conclusions

GS typically presents as a mass in the stomach with an exophytic or mixed growth pattern, moderate homogeneous enhancement, and is prone to be accompanied by perigastric lymph node inflammatory reactive swelling. Larger GSs are more likely to be associated with ulcers.

Establishment and characterization of the GC-030-35 cell line derived from gastric hepatoid adenocarcinoma

Purpose

Gastric hepatoid adenocarcinoma is a rare subtype of primary gastric cancer and is a high-grade form of malignancy. However, the pathogenesis and molecular biology of gastric hepatoid adenocarcinoma remain poorly understood. The aim of this study was to establish and characterize a new human gastric hepatoid adenocarcinoma cell line, GC-030-35.

Materials and methods

The GC-030-35 cell line was established from tumor cells from a 58-year-old Chinese man with gastric hepatoid adenocarcinoma. The cultured cells underwent immunocytochemistry and flow cytometry to confirm the tumor cell phenotype. RNA sequencing was performed to analyze the differences in gene expression between GC-030-35 cells compared with normal gastric epithelial cells. A zebrafish assay was performed. Gene enrichment analysis and interrogation of the bioinformatics databases, the Gene Ontology (GO) database and the Kyoto Encyclopedia of Genes and Genomes (KEGG) database, were used for pathway analysis.

Results

Flow cytometry analysis of the GC-030-35 cells showed a positive expression rate for CD44+ of 10.7%, high cell clonality, an average plating efficiency of 32%, cell-doubling time of 29.2 hours, and cell proliferation for >15 generations in serial culture. The zebrafish assay showed the ability of the GC-030-35 cells to proliferate, promote angiogenesis, and metastasize. RNA sequencing identified the functional clustering of 6,601 differentially expressed genes of GC-030-35, which were significantly different when compared with nonneoplastic gastric epithelial cells. Pathway enrichment analysis and interrogation of the GO and KEGG bioinformatics databases identified genes for microbial metabolism in diverse environments (63 genes), metabolism of xenobiotics by cytochrome P450 (CYP450; 25 genes), and the drug metabolism cytochrome P450 (28 genes).

Conclusion

A human gastric hepatoid adenocarcinoma cell line, GC-030-35, was developed and characterized by comparison with normal gastric epithelial cells. Bioinformatics and gene analysis data showed that the CYP450 gene was significantly differentially expressed by GC-030-35 cells.

The Use of CD44 Variant 9 and Ki-67 Combination Can Predicts Prognosis Better Than Their Single Use in Early Gastric Cancer

Purpose

We previously demonstrated that CD44v9 and Ki-67 played an important role in predicting poor prognosis of early gastric cancer (EGC). However, little is known about combined use of both biomarkers as prognostic biomarker. The present study was performed to investigate the significance of CD44v9 and Ki-67 expression as a combination biomarker for EGC.

Materials and Methods

With tissue microarray for 158 EGC tissues, we performed immunohistochemical staining for CD44v9 and Ki-67. The whole patients were divided into three groups (group A, CD44v9-negative/Ki-67–low; group B, neither group A or C; and group C, CD44v9-positive/Ki-67–high). Its clinical significance was re-analyzed with adjustment via propensity score matching (PSM). For validation, we performed bootstrap resampling.

Results

The median follow-up duration was 90.4 months (range, 3.7 to 120.4 months). In the comparison according to CD44v9/Ki-67 expression, the combined use of the two biomarker clearly separated the three groups by 5-year survival rates (5-YSR, 96.3%, 89.8%, and 76.8% in group A, B, and C, respectively; p=0.009). After PSM, 5-YSR were 97.7% and 76.8% in group A+B and group C, respectively (p=0.002). Multivariable analysis demonstrated that group C had independently poor prognosis (hazard ratio, 9.137; 95% confidence interval, 1.187 to 70.366; p=0.034) compared with group A. Bootstrap resampling internally validated this result (p=0.016).

Conclusion

This study suggests that both positive CD44v9 and high Ki-67 expression are associated with poor prognosis in EGC, and the combined use of these markers provides better prognostic stratification than the single use of them.

LncRNA ZEB2-AS1 contributes to the tumorigenesis of gastric cancer via activating the Wnt/β-catenin pathway

Studies have shown that long noncoding RNA Zinc finger E-box-binding homeobox 2 antisense RNA 1 (ZEB2-AS1) is involved in the progression of lung cancer, bladder cancer, and hepatocellular carcinoma. However, its role in the pathogenesis of gastric cancer remains unknown. The Wnt/β-catenin pathway contributes to the development of gastric cancer. ZEB2-AS1 expression was firstly detected in the gastric carcinoma tissue samples as well as in gastric cancer cells. Knockdown of ZEB2-AS1 was performed by ZEB2-AS1-shRNA, and the viability, migration, invasion, and apoptosis of gastric cancer cells were determined by CCK-8, scratch assay, transwell, and flow cytometry, respectively. Furthermore, levels of Ki-67, PCNA, VEGF, MMP9, epithelial-mesenchymal transition (EMT) markers (E-cadherin, Vimentin and ZEB2), cleaved caspase 3/8/9 and PARP, active β-catenin, c-Myc, cyclinD1, and AXIN2 were assayed by Western blot or real-time PCR. Additionally, the role and mechanism of ZEB2-AS1 were confirmed in a xenograft nude mouse model. We found ZEB2-AS1 expression was increased in gastric carcinoma samples, and it was correlated with tumor progression. Also, its expression was elevated in gastric cancer cells. Knockdown of ZEB2-AS1 reduced the proliferation, migration, invasion, and EMT, but increased the apoptosis of gastric carcinoma cells. Furthermore, ZEB2-AS1 downregulation remarkably suppressed the expression of Ki-67, PCNA, VEGF and MMP9, and the activation of Wnt/β-catenin signaling, whereas elevated the levels of cleaved caspase 3/8/9 and PARP in gastric cancer cells. And ZEB2 overexpression reversed the effects of ZEB2-AS1 downregulation on the proliferation, EMT and inactivation of Wnt/β-catenin signaling. Additionally, ZEB2-AS1 knockdown inhibited tumor growth, Ki-67 staining, and the expression of VEGF, MMP9, active β-catenin, c-Myc, cyclinD1, and AXIN2 in mice. In conclusion, ZEB2-AS1 promotes the tumorigenesis of gastric carcinoma that is related to the upregulation of ZEB2 and the activation of the Wnt/β-catenin pathway.

Establishment and Characterization of gc-006-03, a Novel Human Signet Ring Cell Gastric Cancer Cell Line Derived from Metastatic Ascites

Signet ring cell gastric cancer (SRCGC) is a special type of gastric cancer with rapid progression and poor prognosis. However, few available SRCGC cell lines from Chinese patients can be used for research, the molecular mechanism of its growth and metastasis is still incompletely understood. In this study, we established and characterized a novel SRCGC cell line, gc-006-03.The cells showed a tendency to pile up without contact inhibition. G-band karyotypes of gc-006-03 were revealed hypotriploid with a modal chromosome number of 51. Immunohistochemistry analysis showed that the cells were positive for CEA, CK7, CDX2 and Ki-67(45%), and negative for CK20, TTF1and Li-cadherin. Flow cytometry analysis showed that gc-006-3 had 25% of CD44⁺ cells. The cells possessed strong clonality and high plating efficiency, and the doubling time was 36h. The cells grew vigorously for more than 100 passages in serial culture. Meanwhile, the cells showed a high rate of tumor formation. Tumors were observed in all of the nude mice (5/5) given injections of the cells. The metastatic capability of the cell line was found in zebrafish injected the cells. The results of whole genome sequencing revealed the unique genomic characteristics of gc-006-03. In summary, this new stable cell line may be useful in basic and clinical research on gastric signet ring cell carcinoma.