Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0024623 (gastric cancer)
 36,219 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Despite a decline in the incidence in Western countries, gastric cancer is still the second most common cause of cancer-related death worldwide. Many advances have been made in diagnosis and treatment of gastric cancer in the last decades but the prognosis for gastric cancer patients remains disappointing, especially in more advanced stages. The poor outcome associated with surgical resection with curative intent has generated intensive investigation of combined modality treatment approaches including systemic chemotherapy and radiotherapy to prevent recurrences and improve survival. In this setting the use of perioperative chemotherapy or postoperative chemoradiotherapy has demonstrated to give survival benefits. In advanced disease, major improvements of the last years are represented by the introduction of oral fluoropyrimidines and drugs such as docetaxel or irinotecan and the demonstration of efficacy of the anti-HER2 agent trastuzumab.
 ...
PMID:Chemotherapy for locally advanced and metastatic gastric cancer: state of the art and future perspectives. 2049 40

Overexpression/amplification of human epidermal growth factor receptor (HER)2/neu (erbB-2) oncogene plays a causal role in carcinogenesis and correlates with a poor clinical prognosis. However, little is known about HER2 in gastric cancer. In this study, we explored the pharmacological activities of natural triterpenoid corosolic acid (CRA) in HER2 signaling and its role in gastric cancer development and progression. In this study, CRA dramatically inhibited HER2 expression in a dose- and time-dependent manner, effectively inhibited cell proliferation, and induced G(0)/G(1) arrest through the induction of p27(kip1) and cyclin D(1) down-regulation. CRA exposure enhanced apoptotic cell death, as confirmed by caspase-3 and poly (ADP-ribose) polymerase cleavage activities. CRA inhibited signaling pathways downstream of HER2, including phospho-proteins such as Akt and Erk. In addition, CRA combined with adriamycin and 5-fluorouracil enhanced this growth inhibition, but not with docetaxel and paclitaxel. These findings demonstrate that CRA suppresses HER2 expression, which in turn promotes cell cycle arrest and apoptotic cell death of gastric cancer cells, providing a rationale for future clinical trials of CRA in the treatment of HER2-positive gastric cancers.
 ...
PMID:Down-regulation of human epidermal growth factor receptor 2/neu oncogene by corosolic acid induces cell cycle arrest and apoptosis in NCI-N87 human gastric cancer cells. 2052 55

Trastuzumab-based therapy has been shown to confer overall survival benefit in HER2-positive patients with advanced gastric cancer in a large multicentric trial (ToGA study). Subgroup analysis identified adenocarcinomas of the stomach and gastroesophageal (GE) junction with overexpression of HER2 according to immunohistochemistry (IHC) as potential responders. Due to recent approval of trastuzumab for HER2 positive metastatic gastric and GE-junction cancer in Europe (EMEA) HER2 diagnostics is now mandatory with IHC being the primary test followed by fluorescence in situ hybridization (FISH) in IHC2+ cases. However, in order to not miss patients potentially responding to targeted therapy determination of a HER2-positive status for gastric cancer required modification of scoring as had been proposed in a pre-ToGA study. To validate this new HER2 status testing procedure in terms of inter-laboratory and inter-observer consensus for IHC scoring a series of 547 gastric cancer tissue samples on a tissue microarray (TMA) was used. In the first step, 30 representative cores were used to identify specific IHC HER2 scoring issues among eight French and German laboratories, while in the second step the full set of 547 cores was used to determine IHC HER2 intensity and area score concordance between six German pathologists. Specific issues relating to discordance were identified and recommendations formulated which proved to be effective to reliably determine HER2 status in a prospective test series of 447 diagnostic gastric cancer specimens.
 ...
PMID:HER2 diagnostics in gastric cancer-guideline validation and development of standardized immunohistochemical testing. 2066 45

We aimed to elucidate the clinical significance of the expressions of HER2, epidermal growth factor receptor (EGFR), insulin-like growth factor receptor (IGF-1R), and vascular endothelial growth factor receptor 1, 2, 3 (VEGF-R1, VEGF-R2, and VEGF-R3) in gastric cancer. The study group comprised 57 patients who had undergone gastrectomy at the National Cancer Center Hospital and subsequently received first-line chemotherapy (S-1 monotherapy [n=29] or irinotecan+cisplatin [n=28]) for recurrent or residual tumors. We performed immunohistochemical analysis of formalin-fixed paraffinembedded specimens of surgically removed primary tumors to determine the expressions of HER2, EGFR, IGF-1R, and VEGFR1 in tumor cells and the expressions of VEGF-R1, VEGF-R2, and VEGF-R3 in tumor stromal vessels. The expressions of HER2 (p=0.017) and IGF-1R (p=0.025) were significantly more common in intestinal type tumors than in diffuse type. The protein expressions did not correlate with tumor response in either chemotherapy-regimen group. Among the patients who underwent S-1 monotherapy, those with cytoplasmic VEGF-R1-positive tumors had significantly shorter progression-free survival (logrank, p=0.017). In the survival analysis of all the patients, coexpression of membranous IGF-1R and VEGF-R3 in stromal vessels was the most significant predictor of poor survival (hazard ratio, 1.82; 95% CI, 1.31-2.63; p<0.001). The results of our study will facilitate more efficient use of molecular targeted agents in patients with gastric cancer.
 ...
PMID:[Impact of HER2, EGFR, IGF-1R, and VEGFR expressions on the outcome of chemotherapy for advanced gastric cancer]. 2071 73

Gastric cancer (GC) is an important cause of morbidity and mortality worldwide. In addition to environmental factors, genetic factors also play an important role in GC etiology, as demonstrated by the fact that only a small proportion of individuals exposed to the known environmental risk factors develop GC. Molecular studies have provided evidence that GC arises not only from the combined effects of environmental factors and susceptible genetic variants but also from the accumulation of genetic and epigenetic alterations that play crucial roles in the process of cellular immortalization and tumorigenesis. This review is intended to focus on the recently described basic aspects that play key roles in the process of gastric carcinogenesis. Genetic variation in the genes DNMT3A, PSCA, VEGF, and XRCC1 has been reported to modify the risk of developing gastric carcinoma. Several genes have been newly associated with gastric carcinogenesis, both through oncogenic activation (MYC, SEMA5A, BCL2L12, RBP2 and BUBR1) and tumor suppressor gene inactivation mechanisms (KLF6, RELN, PTCH1A, CLDN11, and SFRP5). At the level of gastric carcinoma treatment, the HER-2 tyrosine kinase receptor has been demonstrated to be a molecular target of therapy.
 ...
PMID:Genetic and epigenetic alteration in gastric carcinogenesis. 2105 51

Surgery is the only curative therapy for gastric cancer. In the metastatic setting the objective of treatment is to manage symptoms, improve quality of life and prolong survival, but current treatment options have limited efficacy and some of them exhibit unfavourable toxicity profiles. Fluoropyrimidine, taxanes and platinum-based regimens are used most frequently and offer a response rate of 30-50% with a median overall survival of =1 year. These discouraging data support the need for new therapeutic strategies based on targeted drugs. Trastuzumab, a monoclonal antibody against HER2, has shown survival benefits when given with chemotherapy in all setting of HER2-positive breast cancer patients. The ToGA trial, the first study evaluating the efficacy and safety of adding trastuzumab to chemotherapy in HER-2 positive advanced gastric cancer, showed a significant superiority of combination over chemotherapy alone. Based on these results trastuzumab combined with a cisplatin and fluoropyrimidine regimen appear the new reference treatment for HER-2 positive metastatic gastric cancer.
 ...
PMID:Human epidermal growth factor receptor 2 (HER2) in gastric cancer: a new therapeutic target. 2112 4

Although medical treatment has been shown to improve quality of life and prolong survival, no significant progress has been made in the treatment of advanced gastric cancer (AGC) within the last two decades. Thus, the choice of optimum standard first-line chemotherapy regimen for AGC remains debatable, and most responses to chemotherapy are partial and of short duration, with a median survival of approximately 7-11 mo and survival at 2 years rarely more than 10%. Recently, remarkable progress in tumor biology has led to the development of new agents that target critical aspects of oncogenic pathways. For AGC, several molecular targeting agents are now under evaluation in international randomized studies, and trastuzumab, an anti-HER2 monoclonal antibody, has shown antitumor activity against HER-2 positive AGC. However, this benefit is limited to only about 20% of patients with AGC (patients with HER-2 positive AGC). Therefore, there remains a critical need for both the development of more effective agents and the identification of predictive and prognostic molecular markers to select those patients who will benefit most from specific chemotherapeutic regimens and targeted therapies.
 ...
PMID:Recent advances in chemotherapy for advanced gastric cancer. 2116 Jun 59

Molecular therapies targeting HER2 are part of the established drug armamentarium in breast carcinoma. Now the ToGA trial, an international multicenter phase III clinical study, involving 24 countries globally, has shown that the anti-HER2 humanized monoclonal antibody Trastuzumab is effective in prolonging survival in HER2-positive carcinoma of the stomach and the gastroesophageal junction (GEJ). Similarly to breast carcinoma, >20% of gastric cancers show HER2 overexpression and/or amplification, and this percentage increases to 33% in GEJ tumors. Thus, as in breast carcinoma, pathologists are now asked to evaluate HER2 status in gastric carcinoma samples. As validated in the ToGA trial, the HER2 testing criteria that must be used in evaluating both gastric carcinoma biopsies and surgical specimens significantly differ from those routinely applied in breast carcinoma. The main variations with regard to the pattern of reactivity in HER2-expressing cells are as follows: the completeness of membrane staining is not a "conditio sine qua non" and the number of stained cells necessary to consider a case as positive is different. We must also take note of the much more frequent heterogeneity of HER2 positivity in gastric cancer compared with breast carcinoma and the less stringent correlation between HER2 amplification and protein overexpression that is observed in gastric carcinoma, where more than 20% of cases may carry HER2 amplification, although of low level, without HER2 expression. In these patients, in the ToGA trial, there was no apparent benefit from adding Trastuzumab to chemotherapy: for this reason the European Medicines Agency, while approving usage of Trastuzumab for metastatic adenocarcinoma treatment, indicated HER2 testing by immunohistochemistry as first evaluation assay, followed by fluorescence in situ hybridization in 2+ equivocal cases. HER2 testing in gastric carcinoma is a new field, opening several opportunities: for patients with gastric cancer, this is a new promising therapeutic option; for pathologists, strengthening our role in therapy selection and emphasizing our duty of providing accurate and reproducible HER2 testing results; for all interested in understanding the biology of gastric and GEJ cancer and in discovering new possible molecular therapy targets.
 ...
PMID:HER2 testing in gastric cancer. 2116 38

HER2 positivity is thought to be a negative prognostic factor in gastric cancer (GC), correlating with poor survival rates. Reported HER2-positivity rates in GC have varied widely (6-35%). Objective of this study is to determine rate of positivity and describe clinical and pathological characteristics of HER-2(+) GC. 100 GC tumour samples were centrally screened by immunohistochemistry and FISH. 9% of cases were positive. More positivity HER2 was found in advanced stages (III/IV) vs. early stages (I/II)(p=0.045) ; intestinal histology subtype vs diffuse/ mixed (p=0.045) and gastro-oesophageal junction cancer vs GC ( p=0.005).
 ...
PMID:[HER2 expression in gastric cancer in Peru]. 2126 59

Trastuzumab, a HER2 directed treatment has shown clinical benefit in HER2 amplified gastric cancer. This study demonstrated the potent antitumor activity of HM781-36B, a quinazoline-based irreversible pan-HER inhibitor, in HER2 amplified gastric cancer cells (SNU216 and N87) in vitro and in vivo. HM781-36B inhibited phosphorylation of HER family and downstream signaling molecules, and induced apoptosis and G1 arrest. Furthermore, HM781-36B exerted synergistic effects with chemotherapeutic agents in both HER2 amplified and HER2 non-amplified gastric cancer cells. Therefore, HM781-36B may be useful for the treatment of HER2 amplified gastric cancer alone or in combination with chemotherapeutic agents.
 ...
PMID:Antitumor activity of HM781-36B, an irreversible Pan-HER inhibitor, alone or in combination with cytotoxic chemotherapeutic agents in gastric cancer. 2130 21


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>