Prognostic significance of immunohistochemical expression of EGFR and C-erbB-2 oncoprotein in curatively resected gastric cancer

Human epidermal growth factor receptor-2 gene expression positivity determined by silver in situ hybridization/immunohistochemistry methods and associated factors in a cohort of Sri Lankan patients with gastric adenocarcinoma: a prospective study

OBJECTIVE

Positive human epidermal growth factor 2 (HER2) expression and its predictive clinicopathological features remain unclear in Sri Lankan gastric cancer (GC) patients. Here, we aimed to determine GC HER2 status predictors by analyzing associations between clinicopathological features and HER2 expression using immunohistochemistry (IHC) and silver in situ hybridization (SISH).

METHODS

During this 4-year prospective study, clinicopathological data were collected from participants in the National Hospital of Sri Lanka. HER2 IHC and SISH were performed using commercial reagents. Using chi-square tests, associations of HER2-IHC/SISH with clinicopathological features were analyzed.

RESULTS

Overall, 145 GC patients were included, 69 had gastrectomies and 76 had biopsies. Positive HER2 expression by IHC was associated with age <60 years, high T stage (assessed pathologically in resections and radiologically in biopsies), high nuclear grade, tumor necrosis, mitosis >5/high-power field, with additional perineural invasion and lymphovascular invasion in resections. These features, excluding lymphovascular invasion but including male sex, were associated with HER2 expression by SISH.

CONCLUSIONS

Age <60 years, high nuclear grade, tumor necrosis, and perineural invasion are associated factors of HER2 status. These could be used to triage GC patients for HER2 status testing in limited resource settings where IHC/SISH analysis is costly.

Deep muscularis propria tumor invasion without lymph node metastasis as a unique subclassification of stage IB gastric cancer: a retrospective study

Background

The prognosis difference based on the depth of tumor muscularis propria invasion in gastric cancer (GC) was still debated, and therapy strategy for stage IB GC patient required further investigation.

Methods

A total of 380 patients with pT2 GC after radical surgery were retrospectively analyzed, including 185 in superficial muscularis propria (sMP) group and 195 in deep muscularis propria (dMP) group.

Results

The overall survival (OS) was significantly better for patients in sMP group than for patients in dMP group (P = 0.007). In multivariate analysis, depth of tumor invasion, pN stage, age, primary location, positive expression of p53, elevated maximal LDH, elevated initial CA19-9 and AFP level were independent prognostic factors for OS. The sMP group had a significantly better OS than dMP group (P = 0.014) in pN0 stage. After further stratification, the survival outcomes were not significantly different between deep muscularis propria tumor invasion without lymph node metastasis (dMPN0) group (stage IB) and superficial muscularis propria tumor invasion with stage 1–2 lymph node metastasis (sMPN1–2) group (stage II) (P = 0.100). Patients with adjuvant chemotherapy had a statistically better survival than those without in dMPN0 group (P = 0.045) and dMPN0 patients with adjuvant chemotherapy had better OS than sMPN1–2 patients (P = 0.015). In addition, greater postoperative survival could be observed in sMPN0 patients than dMPN0 patients in p53-positive group (P = 0.002), and similar OS could be seen between dMPN0 patients with p53-positive and T2N1–2 patients (P = 0.872).

Conclusion

As a unique subclassification of stage IB GC, appropriate adjuvant chemotherapy should be considered for patients with dMPN0 stage. In addition, positive expression of p53, elevated LDH could be potential factors in identifying the different prognoses for stage IB GC patients.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12876-021-02090-z.

Expression of HER2/c-erbB-2, EGFR Protein in Gastric Carcinoma and its Clinical Significance

Objective

To investigate the HER2/c-erbB-2, epidermal growth factor receptor (EGFR) protein expression in gastric cancer and association with patients’ clinical pathology characteristics and prognosis.

Methods

HER2/c-erbB-2 and EGFR protein expression was examined by immunohistochemical assay in gastric cancer tissue and corresponding paired normal gastric tissue of 67 patients of gastric carcinoma. The HER2/c-erbB-2, EGFR protein positive expression rate in cancer tissue and normal gastric tissue were compared. The correlation between HER2/c-erbB-2, EGFR protein positive expression and patients’ clinical pathology characteristics and survival was evaluated.

Results

The positive expression rate of HER2/c-erbB-2 in the cancer and paired normal gastric tissues were 32.8% (22/67) and 4.5% (3/67), respectively with statistical difference (p<0.05). And the positive expression rate of EGFR in cancer and paired normal gastric tissues were 41.8% (28/67) and 5.9 (4/67), respectively, with statistical difference (p<0.05). HER2/c-erbB-2 positive expression in cancer tissue was significant correlated with the pathology grading (p<0.05), tumor invasion depth (p<0.05) and local regional lymph node metastasis (p<0.05); EGFR positive expression in cancer tissue was significant correlated with the tumor invasion depth (p<0.05) and local regional lymph node metastasis (p<0.05). The median survival time was 13.14 and 23.6 months respectively for HER2/c-erbB-2 positive and negative expression groups respectively with statistical difference ( HR=2.26, 9%CI:1.06-4.80, p<0.05). However, the median survival time was 15.47 and 22.87 months for EGFR positive and negative expression groups respectively, without statistical difference (HR=1.78, 9%CI:0.96-3.29, p>0.05).

Conclusion

Positive expression of HER2/c-erbB-2 and EGFR proteins in cancer tissue was significant higher than normal gastric tissue and have significant correlation with prognosis.

The Prognostic Significance of c-MET and EGFR Overexpression in Resected Gastric Adenocarcinomas

OBJECTIVES

Epidermal growth factor receptor (EGFR) and c-MET are tyrosine kinase growth factor receptors implicated in gastric cancer (GC), and their pathways appear to be interdependent. The aim of this study was to investigate the prognostic value of EGFR and c-MET protein overexpression by immunohistochemistry in Canadian patients with resected GC and correlate it with clinicopathologic characteristics and overall survival (OS).

MATERIALS AND METHODS

Tissue microarray blocks were constructed from 120 resected GCs stained with EGFR and c-MET and scored semiquantitatively (0 to 3+). Each receptor's expression was compared with clinicopathologic characteristics and survival. Descriptive statistics, Kaplan-Meyer, and Cox regression were used for statistical analyses.

RESULTS

Of the 113 interpretable cases, overexpression of EGFR and c-MET was noted in 17 (15%) and 65 (57%), respectively; coexpression of EGFR and c-MET was observed in 12 (10%) of GC. EGFR and c-MET overexpression correlated with poor OS: median 13 versus 30 months in EGFR positive versus negative GC (hazard ratio [HR]=1.67, P=0.11); 27 versus 49 months in c-MET positive versus negative GC (HR=1.17, P=0.49), respectively. GC coexpressing EGFR and c-MET was significantly correlated with poor survival: 12 versus 29 months in double-positive versus rest of tumors both in univariate (HR=2.62, P=0.003) and multivariate analyses (HR=2.58, P=0.01).

CONCLUSIONS

This study describes the prevalence and prognostic value of EGFR and c-MET in a Canadian population of patients undergoing curative intent resection for GC. Both c-MET and EGFR overexpression trended toward poor OS, but only the group with EGFR+/c-MET+ GC reached statistical significance on multivariate analysis.

Clinicopathologic and prognostic significance of human epidermal growth factor receptor in patients with gastric cancer: An updated meta-analysis

Purpose

The aim of this update meta-analysis was to clarify the clinicopathologic and prognostic significance of human epidermal growth factor receptor(EGFR) expression in gastric cancer patients.

Experimental Design

Several electronic databases were searched from January 1970 to May 2016. The odds ratio (OR) was calculated to assess the association between EGFR expression and pathological parameters. The hazard ratio (HR) and 95% CI were calculated to explore the relationship between EGFR expression and overall survival.

Results

Finally 7229 patients with gastric cancer from 25 eligible studies were included in the present meta analysis. High EGFR expression was found to be significantly related with tumor differentiation (OR=1.96, 95%CI: 1.14-3.34, Z=2.43, P=0.015), lymph node metastasis (OR=2.20, 95% CI: 1.63-2.96, Z=5.17, P=0.001), and tumor stage (OR=2.13, 95% CI: 1.35-3.36, Z=3.25, P=0.001). However, high EGFR expression was not significantly associated with invasion depth (OR=2.09, 95% CI: 0.4-11.05, Z=0.87, P=0.385). The pooled HR suggested that high EGFR expression was significantly correlated with overall survival (HR=1.19, 95% CI 1.04-1.37, Z=2.44, P=0.015).

Conclusions

The present meta-analysis demonstrated that high EGFR expression significantly predicts poor prognosis, suggesting that high EGFR expression may serve as a predictive biomarker for poor prognosis in patients with gastric cancer.

The clinicopathological parameters and prognostic significance of HER2 expression in gastric cancer patients: a meta-analysis of literature

Background

Human epidermal growth factor receptor-2 (HER2) is regarded as an important and promising target in the treatment of HER2-positive breast cancers. However, the correlation of clinicopathological characteristics and prognostic significance of HER2 overexpression in gastric cancer patients remains unclear. Our aim was to clarify this issue.

Methods

Embase, PubMed, and the Cochrane Library were searched for relevant articles published up to May 2016. Outcomes of interest contained sex, age, tumor size, tumor site, tumor node metastasis (TNM) stage, distant metastasis, lymph node metastasis, Lauren’s classification, differentiation grade, lymphovascular invasion, neural invasion, and multivariate analysis data for overall survival.

Results

A total of 41 studies of 17,494 gastric cancer patients were identified with HER2 test. HER2 positive rate was 19.07% (95% CI = 9.16, 28.98). There existed statistical significance between HER2 overexpression and patients’ prognosis (RR = 1.47, 95% CI = 1.09, 1.98). Male patients (OR = 1.48, 95% CI = 1.34, 1.65), proximal tumors (OR = 1.25, 95% CI = 1.07, 1.47), intestinal-type tumors (OR = 3.37, 95% CI = 2.54, 4.47), advanced stage cancers (OR = 1.35, 95% CI = 1.10, 1.66), lymph node metastasis (OR = 1.26, 95% CI = 1.14, 1.41), well-differentiated cancers (OR = 1.79, 95% CI = 1.15, 2.76), and distant metastasis (OR = 1.91, 95% CI = 1.08, 3.38) were correlated with higher HER2 expression rates. However, no statistical differences existed in age, tumor size, lymphovascular invasion, or neural invasion. Subgroup analysis revealed that HER2 expression rates reported in articles from Asian (19.52%) countries were quantitatively higher than those from European (16.91%) areas. Results were consistent with those reports that define HER2 status according to trastuzumab for gastric cancer (ToGA) criteria.

Conclusion

This study showed that HER2 overexpression was associated with poor prognosis in gastric cancer patients. HER2 positive rates may be associated with sex, tumor site, TNM staging system, distant metastasis, lymph node metastasis, Lauren’s classification, and differentiation grade in gastric cancer patients. The HER2 expression rate in Asians may be higher than that in Europeans. This study offers a convenient way for doctors to select patients for relevant HER2 detection and following treatment.

Electronic supplementary material

The online version of this article (doi:10.1186/s12957-017-1132-5) contains supplementary material, which is available to authorized users.

IGF-IR cooperates with ERα to inhibit breast cancer cell aggressiveness by regulating the expression and localisation of ECM molecules

IGF-IR is highly associated with the behaviour of breast cancer cells. In ERα-positive breast cancer, IGF-IR is present at high levels. In clinical practice, prolonged treatment with anti-estrogen agents results in resistance to the therapy with activation of alternative signaling pathways. Receptor Tyrosine Kinases, and especially IGF-IR, have crucial roles in these processes. Here, we report a nodal role of IGF-IR in the regulation of ERα-positive breast cancer cell aggressiveness and the regulation of expression levels of several extracellular matrix molecules. In particular, activation of IGF-IR, but not EGFR, in MCF-7 breast cancer cells results in the reduction of specific matrix metalloproteinases and their inhibitors. In contrast, IGF-IR inhibition leads to the depletion by endocytosis of syndecan-4. Global important changes in cell adhesion receptors, which include integrins and syndecan-4 triggered by IGF-IR inhibition, regulate adhesion and invasion. Cell function assays that were performed in MCF-7 cells as well as their ERα-suppressed counterparts indicate that ER status is a major determinant of IGF-IR regulatory role on cell adhesion and invasion. The strong inhibitory role of IGF-IR on breast cancer cells aggressiveness for which E2-ERα signaling pathway seems to be essential, highlights IGF-IR as a major molecular target for novel therapeutic strategies.

Evaluation of the Expression of the Human Epithelial Receptor 2 (HER2) in Gastric Carcinoma

Objective. To evaluate the HER2 expression on gastric adenocarcinoma from a Brazilian population and also to analyze the relations between the receptor and clinical characteristics, as well as the survival status. Materials and Methods. A retrospective analysis was conducted from January of 2008 to July of 2012, considering only gastrectomies with curative intent. Tumors were tested for HER2 status using immunohistochemistry. The relation between HER2 status and clinical aspects, surgical findings, and survival were also analyzed. Results. 222 patients with gastric carcinoma were submitted to surgery during that period, but only 121 (54,5%) were with curative intention. The immunohistochemistry revealed that 4 patients (3,3%) were HER2-positive, 6 patients (4,9%) HER2-undetermined, and 111 patients (91,7%) HER2-negative. There was no statistical concordance between HER2 status and survival or the clinical aspects. Conclusion. The HER2 overexpression rate was very low in this Brazilian population sample and cannot be considered as a prognostic factor.

Clinical utility of HER2 assessed by immunohistochemistry in patients undergoing curative resection for gastric cancer

Purpose

We sought to determine whether human epidermal growth factor receptor 2 (HER2) and vascular endothelial growth factor (VEGF) expression were independent prognostic factors for gastric cancer (GC).

Patients and methods

A total of 678 consecutive patients with GC undergoing curative surgery between October 2010 and December 2012 had resected tissue examined for HER2 and VEGF expression using immunohistochemistry. Immunohistochemical expression of HER2 was analyzed using the DAKO-HercepTest™ and scored according to published reports. VEGF expression was calculated by multiplying the score for the percentage of positive cells by the intensity score. We defined positive expression as a score of 1+, 2+, or 3+, and a score of 0 was defined as negative expression. We compared these results to clinicopathological characteristics, including overall survival (OS).

Results

Multivariate analysis revealed that HER2 expression was independently associated with shorter OS (hazard ratio [HR], 1.55; 95% confidence interval [CI], 1.10–2.18; P=0.01) and with higher tumor–nodes–metastasis stage (HR, 3.88; 95% CI, 2.67–5.64; P<0.001) in patients with GC. VEGF expression was not associated with OS (HR, 1.25; 95% CI, 0.86–1.82; P=0.24). HER2 expression was still identified as an independent prognostic factor in Stage II–III patients treated with surgery and adjuvant chemotherapy (P=0.004) but not in patients who received surgery alone (P=0.61). Among patients with Stage III GC, those without HER2 expression survived longer with adjuvant chemotherapy (median 43.9 vs 32.2 months, respectively; P=0.04), whereas those with HER2 expression did not (median 37.1 vs 33.9 months, respectively; P=0.67).

Conclusion

HER2 expression is independently associated with OS in GC, especially in patients who are at higher risk and receive adjuvant chemotherapy after curative resection. HER2 expression may have important clinical utility in directing adjuvant treatment for Stage III GC patients.

The prognostic impact of EGFR, ErbB2 and MET gene amplification in human gastric carcinomas as measured by quantitative Real-Time PCR

PURPOSE

Identification of critical genes which play pivotal roles in controlling tumor growth and survival will establish the basis for developing therapeutic targets. In this study, we focused on frequencies of EGFR, ErbB2 and MET gene amplification in gastric cancer patients to develop personalized medicine to improve the treatment.

METHOD

EGFR, ErbB2 and MET gene amplification, and mRNA expression were analyzed by the quantitative Real-Time PCR in paraffin-embedded samples from 115 patients with gastric cancer.

RESULTS

EGFR, ErbB2 and MET genes were amplified in 11.3 % (13/115), 6.1 % (7/115) and 19.1 % (22/115) of cancerous specimens, respectively. The correlation coefficient test clearly indicated that gene amplification in these three genes was positively correlated with mRNA transcription (EGFR: R = 0.631, p = 0.009; ErbB2: R = 0.652, p = 0.023; MET: R = 0.715, p < 0.001). EGFR and MET gene amplification was significantly associated with Ki-67 MI (p = 0.022 and p = 0.015). MET amplification was also significantly associated with age of ≥60 years (p = 0.021) and tumor size of ≥5 cm (p = 0.032). MET amplification, but not EGFR and ErbB2, was a significant prognostic factor in poor survival among patients with gastric cancer.

CONCLUSIONS

EGFR, ErbB2 and MET genes are frequently amplified in gastric carcinoma. EGFR, ErbB2 and MET gene amplification is positively correlated with mRNA transcription. MET gene amplification correlates with a poor prognosis and poor survival in gastric carcinomas.

Role of human epidermal growth factor receptor 2 in gastric cancer: biological and pharmacological aspects

Amplification of the human epidermal growth factor receptor 2 (HER2) gene and overexpression of the HER2 protein is found in 15%-20% of patients with gastric and gastroesophageal junction cancer. The degree of HER2 overexpression and amplification varies with the location of the carcinoma, with higher expression in the gastroesophageal and proximal parts compared to the distal parts of the stomach. Further, HER2 overexpression and amplification also seems to be related to the Lauren histological classification, with higher levels found in the intestinal phenotype compared to the diffuse and mixed types. The prognostic properties of HER2 overexpression and amplification are still under debate, but a large number of studies seem to indicate that HER2 is a negative prognostic factor. The usefulness of HER2 targeted therapy in gastric cancer was demonstrated in the ToGA trial, where HER2-positive patients with advanced gastric and gastroesophageal junction adenocarcinoma were randomized to receive 5-FU/capecitabine and cisplatin, either alone or in combination with trastuzumab. A statically significant gain in overall survival was seen in patients who received the combined treatment of trastuzumab and chemotherapy. Patients with a strong overexpression of the HER2 protein (IHC3+) specifically benefited from the treatment, with a median overall survival of 17.9 mo. As a consequence of the positive results of the ToGA trial, patients with advanced gastric or gastroesophageal junction adenocarcinoma are now routinely tested for HER2. The ToGA trial must be characterized as a landmark in the treatment of gastric cancer and it has paved the way for a number of new HER2 targeted compounds such as pertuzumab, ado-trastuzumab emtansine, lapatinib, afatinib, and dacomitinib, which are currently undergoing phase II and III clinical testing. Overall, this review will discuss the current status of HER2 in gastric and gastroesophageal junction cancer and the future direction in relation to HER2 target therapy.

The effect of epiregulin on epidermal growth factor receptor expression and proliferation of oral squamous cell carcinoma cell lines

Background

Epiregulin (EPR) is a novel member of the epidermal growth factor (EGF) family. It has been shown to promote wound healing in oral epithelium, enhance proliferation of other epithelial tissues, and is involved in several epithelial-related malignancies such as colorectal, lung, and bladder carcinoma. More recently, EPR transcripts were found to be high in a study on archival oral squamous cell carcinoma (OSCC) specimens. This implies that EPR may be responsible for the progression of OSCC. The aim of this was to elucidate the effects of EPR on (i) cell morphological changes, (ii) cell proliferation and (iii) receptor expression of the H-series OSCC cell lines.

Methods

The clinicopathological origin and the expression of the epidermal growth factor receptor (EGFR) and ErbB4 receptors of the H-series cell lines were initially characterised. Based on these parameters, two of the H-series cell lines, namely H103 and H357 were selected for downstream experiments. The cell lines were treated with 1 ng/ml, 10 ng/ml, and 20 ng/ml of EPR for 24 and 48 hours in all subsequent experiments. Untreated cells acted as the control which was used for comparison with each treated group. The cell morphological changes, cell proliferation and receptor expression of the OSCC cell lines were evaluated using phase contrast microscopy, 5-bromo-2’-deoxy-uridine (BrdU) assays and flow cytometry respectively. The results were compared and analysed using the student t-test.

Results

There were no appreciable morphological changes in the cells regardless of the dose of EPR tested nor between the different timelines. There were no significant changes in cell proliferation after EPR treatment. As for the effect of EPR on receptor expression, 20 ng/ml of EPR significantly reduced the density of EGFR expression (p value = 0.049) in the H103 cell line after the 24-hour treatment. No other statistically significant changes were detected.

Conclusions

The results show that EPR had no effect on the morphology and proliferativity of OSCC cells. However, the significant decline in EGFR expression after EPR treatment suggests that EPR might play an important role in the regulation of EGFR expression and hence OSCC progression.

Effect of epidermal growth factor receptor status on the outcomes of patients with metastatic gastric cancer: A pilot study

The expression of epidermal growth factor receptor (EGFR) has been linked to clinical outcome in several solid tumors. However, the clinical significance of EGFR (c-erbB1) in gastric cancer remains unclear. The present study was designed to detect the clinical implications of EGFR in the Turkish population. Paraffin-embedded tissue microarrays containing gastric cancer tissue were obtained from 30 patients. EGFR expression was detected using immunohistochemistry. The correlation of this biomarker to the clinicopathological features and survival of patients with gastric cancer was studied. The overall positivity rate of EGFR was 63.3%. EGFR expression was significantly correlated with an improved progression-free survival (PFS) and overall survival (OS) rate (P=0.039 and 0.01, respectively). EGFR expression is a good prognostic marker for patients with gastric cancer.

Metastatic gastric cancer treatment: a little slow but worthy progress

Metastatic gastric cancer is incurable and remains one of the leading causes of cancer-related deaths around the world. Despite the significant progress in its systemic treatment, metastatic gastric cancer is still a major therapeutic challenge for oncologists. Newer chemotherapy regimens and the addition of molecularly targeted agents to chemotherapy seem to provide better clinical outcomes for patients with metastatic gastric cancer. The objective of this article is to review the current treatment approach for this formidable disease.

The prognostic impact of epidermal growth factor receptor in patients with metastatic gastric cancer

Background

The epidermal growth factor receptor (EGFR) is a potential target of anticancer therapy in gastric cancer. However, its prognostic role in metastatic gastric or gastroesophageal junction (GE) cancer has not been established yet.

Methods

EGFR status was analyzed by immunohistochemistry (IHC) in paraffin-embedded samples from 357 patients who received chemotherapy in 4 first-line trials. Automated RNA extraction from paraffin and RT-quantitative PCR were additionally used to evaluate EGFR mRNA expression in 130 patients.

Results

EGFR protein expression (any grade) and overexpression (3+) were observed in 43% and 11% of patients, respectively. EGFR positivity correlated with intestinal type histology (p = 0.05), but not with other clinicopathologic characteristics. Median follow-up was 18.2 months. Median overall survival (OS) was similar in patients with EGFR positive vs. those with EGFR negative tumors, regardless whether positivity was defined as ≥1+ (10.6 vs. 10.9 months, p = 0.463) or as 3+ (8.6 vs. 10.8 months, p = 0.377). The multivariate analysis indicated that EGFR status is not an independent prognostic factor (hazard ratio 0.85, 0.56 to 1.12, p = 0.247). There were also no significant differences in overall survival when patients were categorized according to median (p = 0.116) or quartile (p = 0.767) distribution of EGFR mRNA gene expression. Similar distributions of progression-free survival according to EGFR status were observed.

Conclusions

Unlike different cancer types where EGFR-positive disease is associated with an adverse prognostic value, EGFR positivity is not prognostic of patient outcome in metastatic gastric or GE cancer.

Advanced HER2-positive gastric cancer: current and future targeted therapies

The prognostic value of human epidermal growth factor receptor 2 (HER2) in gastric cancer is controversial. Consensus guidelines have standardized the testing of HER2 status in gastric cancer. Overexpression of this receptor occurs in approximately 20% of gastric and gastro-esophageal junction adenocarcinomas, predominantly those of the intestinal type. Recently, trastuzumab has emerged as the first targeted drug to improve overall survival when combined with chemotherapy in advanced HER2-positive gastric cancer. Primary and secondary resistance to trastuzumab has become a major problem and new strategies to overcome this resistance are needed. A high percentage of advanced HER2-positive gastric cancer patients who progress on trastuzumab therapy are candidates for second-line therapy. New families of targeted drugs, including tyrosine kinase inhibitors (TKIs) such as lapatinib and PF-00299804, mammalian target of rapamycin (mTOR) pathway inhibitors such as everolimus, heat-shock protein 90 (HSP90) inhibitors such as AUY922, HER dimerization inhibitors such as pertuzumab, and antibody-chemotherapy conjugates such as trastuzumab-emtansine (T-DM1), could offer alternative second-line treatments when trastuzumab-based first-line therapy fails.

Bioinformatics analysis with graph-based clustering to detect gastric cancer-related pathways

Despite a dramatic reduction in incidence and mortality rates, gastric cancer still remains one of the most common malignant tumors worldwide, especially in China. We sought to identify a set of discriminating genes that could be used for characterization and prediction of response to gastric cancer. Using bioinformatics analysis, two gastric cancer datasets, GSE19826 and GSE2685, were merged to find novel target genes and domains to explain pathogenesis; we selected differentially expressed genes in these two datasets and analyzed their correlation in order to construct a network. This network was examined to find graph clusters and related significant pathways. We found that ALDH2 and CCNB1 were associated with gastric cancer. We also mined for the underlying molecular mechanisms involving these differently expressed genes. We found that ECM-receptor interaction, focal adhesion, and cell cycle were among the significantly associated pathways. We were able to detect genes and pathways that were not considered in previous research on gastric cancer, indicating that this approach could be an improvement on the investigative mechanisms for finding genetic associations with disease.

HER2 as a Prognostic Marker in Gastric Cancer - A Systematic Analysis of Data from the Literature

Through the recent conduct of the ToGA trial, HER2 has shown to be predictive for the treatment with trastuzumab in advanced gastric and gastro-oesophageal cancer. When it comes to the prognostic properties the situation is different. Despite the fact that it is more than 20 years ago since the first studies demonstrating an association between a positive HER2 status and poor prognosis were published the issue is still controversial. In this current systematic review a large number of studies on HER2 and gastric cancer have been reviewed. The studies included in this review should fulfill the following two criteria. First criterion: The number of patients in each study should be ≥ 100, and the HER2 status should have been determined either by immunohistochemistry (IHC) or in situ hybridization (ISH). Second criterion: The selected articles should include an analysis of the association between the HER2 status and survival or relevant clinicopathological characteristics. Forty-two publications with a total of 12,749 patients fulfilled the two criteria and were reviewed in detail. The majority of the publications (71%) showed that a HER2-postive status measured either by IHC or ISH was associated with poor survival and/or clinicopathological characteristics, such as serosal invasion, lymph node metastases, disease stage, or distant metastases. Based on the current analysis a clear trend towards a potential role for HER2 as a negative prognostics factor in gastric cancer was shown, suggesting that HER2 overexpression and/or amplification is a molecular abnormality that might be linked to the development of gastric cancer.

Evolving standards of care in advanced gastric cancer

Despite its decreasing incidence in western countries, the care of gastric cancer remains a concern, as many patients are diagnosed with advanced disease. Whereas localized gastric cancer has benefited from advances in surgical management and perioperative chemotherapy, patients with unresectable or metastatic disease have a poor prognosis. However, advances in chemotherapy have still arisen, with the onset of more convenient and active schedules of treatment, but no significant breakthrough has been achieved in terms of survival. Recent trials in advanced gastric cancer have been focusing on targeted therapies. This article aims to focus on the current state of the art in terms of chemotherapy for advanced gastric cancer, as well as to describe and explain the rationale and hopes for newer therapies that are currently under investigation.

Clinicopathologic factors associated with HER2-positive gastric cancer and its impact on survival outcomes--a systematic review

With the availability of a therapeutic target and an effective agent in trastuzumab, a systematic examination of the literature to investigate the role of human epidermal growth factor 2 (HER2) as a prognostic factor for survival and its association with clinicopathologic markers may improve treatment. An electronic search of the MEDLINE and PubMed databases (January 1990 to January 2011) was undertaken to identify translational studies that correlated HER2 with clinicopathologic markers and/or survival outcome. This review included 49 studies totaling 11,337 patients. Forty-four percent of patients had Stage I/II, and 56% had Stage III/IV disease. Immunohistochemistry was most commonly used to assess HER2 expression, identifying a median rate of 18% (range, 4-53%) of gastric cancer demonstrating HER2 overexpression. In patients with and without HER2 overexpression, the median 3-year disease-free survival rate was 58% (range, 50-88%) and 86% (range, 62-97%), respectively. Of the 35 studies reporting the impact of HER2 overexpression on survival, 20 studies (57%) reported no difference in overall survival, two studies (6%) reported significantly longer overall survival in patients with HER2 overexpression and 13 studies (37%) reported significantly poorer overall survival in patients with HER2 overexpression. The median overall survival and 5-year survival rate was 21 (range, 10-57) months and 42%, and 33 (range, 13-80) months and 52% in patients with and without HER2 overexpression, respectively. HER2 overexpression appears to be associated with poorer survival and with intestinal-type gastric cancer in this group of patients for whom majority undergone curative gastrectomy.

Clinical significance of EGFR expression in Chinese gastric cancer patients

AIM: To investigate the correlation between epidermal growth factor receptor (EGFR) protein expression and clinicopathological parameters in patients with gastric cancer.

METHODS: The expression of EGFR protein in 775 gastric adenocarcinoma specimens was examined by immunohistochemistry using the EliVisionTM plus kit.

RESULTS: The positive rate of EGFR protein overexpression in gastric adenocarcinoma was 17.03% (132/775). EGFR protein overexpression is associated with tumor invasion depth, histotype, differentiation, and lymph node metastasis (all P < 0.05), but not with sex, age, tumor site, TNM stage, and distant metastasis (all P > 0.05). Multivariate analysis demonstrated that tumor invasion depth, histotype, differentiation, and lymph node metastasis were significant predictors of EGFR protein overexpression in gastric cancer (all P < 0.05).

CONCLUSION: Detection of EGFR protein expression can be used to assess the malignant biological behavior and prognosis of gastric cancer and therefore provides a theoretical target for therapy of gastric cancer.