Phase II study of cetuximab in combination with FOLFIRI in patients with untreated advanced gastric or gastroesophageal junction adenocarcinoma (FOLCETUX study)

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.

Molecular targeted agents for gastric and gastroesophageal junction cancer

Despite recent improvements in surgical techniques and chemotherapy, advanced cancers of the stomach and gastroesophageal junction (GEJ) continue to have poor clinical outcomes. However, molecules intimately related to cancer cell proliferation, invasion, and metastasis have been studied as candidates for molecular targeted agents. Target molecules, such as the epidermal growth factor receptor, vascular endothelial growth factor receptor, and P13k/Akt/mTor pathway, as well as the insulin-like growth factor receptor, c-Met pathways, fibroblast growth factor receptor, and other pathways are considered to be promising candidates for molecular targeted therapy for gastric and GEJ cancer. In this review we focus on the recent developments in targeting relevant pathways in these types of cancer.

What is the reference cytotoxic regimen for advanced gastric cancer: standard versus optimal therapy?

Advanced gastric cancer is an aggressive disease, with continued poor clinical outcomes. In the past two decades, many clinical trials have been conducted, testing chemotherapy agents in different combinations. However, many of these trials have employed aggressive regimens, which may be not suitable for some patients with advanced disease and poor performance status seen in clinical settings. In addition, geographic and ethnic differences in disease pathogenesis/biology, treatment strategies and drug metabolism make universal application of these trial results difficult. Here, we summarize the extant data on chemotherapy agents in gastric cancer, and try to deduce the best combination(s) that may be utilized in this disease, or that may be suitable for particular subgroup patient populations. Importantly, we discuss future directions - how we need to move away from testing various cytotoxic agent permutations and combinations, towards smarter trials that employ targeted therapies.

Gene expression signature analysis identifies vorinostat as a candidate therapy for gastric cancer

BACKGROUND

Gastric cancer continues to be one of the deadliest cancers in the world and therefore identification of new drugs targeting this type of cancer is thus of significant importance. The purpose of this study was to identify and validate a therapeutic agent which might improve the outcomes for gastric cancer patients in the future.

METHODOLOGY/PRINCIPAL FINDINGS

Using microarray technology, we generated a gene expression profile of human gastric cancer-specific genes from human gastric cancer tissue samples. We used this profile in the Broad Institute's Connectivity Map analysis to identify candidate therapeutic compounds for gastric cancer. We found the histone deacetylase inhibitor vorinostat as the lead compound and thus a potential therapeutic drug for gastric cancer. Vorinostat induced both apoptosis and autophagy in gastric cancer cell lines. Pharmacological and genetic inhibition of autophagy however, increased the therapeutic efficacy of vorinostat, indicating that a combination of vorinostat with autophagy inhibitors may therapeutically be more beneficial. Moreover, gene expression analysis of gastric cancer identified a collection of genes (ITGB5, TYMS, MYB, APOC1, CBX5, PLA2G2A, and KIF20A) whose expression was elevated in gastric tumor tissue and downregulated more than 2-fold by vorinostat treatment in gastric cancer cell lines. In contrast, SCGB2A1, TCN1, CFD, APLP1, and NQO1 manifested a reversed pattern.

CONCLUSIONS/SIGNIFICANCE

We showed that analysis of gene expression signature may represent an emerging approach to discover therapeutic agents for gastric cancer, such as vorinostat. The observation of altered gene expression after vorinostat treatment may provide the clue to identify the molecular mechanism of vorinostat and those patients likely to benefit from vorinostat treatment.

Phase II trial of modified FOLFOX6 and erlotinib in patients with metastatic or advanced adenocarcinoma of the oesophagus and gastro-oesophageal junction

BACKGROUND

There is increased recognition that cancers of the upper GI tract comprise distinct epidemiological and molecular entities. Erlotinib has shown activity in patients with adenocarcinoma of the oesophagus/gastro-oesophageal junction (GEJ), but not in distal gastric cancer. mFOLFOX6 is one of several active regimens used to treat adenocarcinoma of the Eso/GEJ. This study evaluates the efficacy and safety of mFOLFOX6 and erlotinib in patients with metastatic or advanced Eso/GEJ cancers.

METHODS

Patients with previously untreated advanced or metastatic Eso/GEJ adenocarcinoma are treated with oxaliplatin 85 mg m(-2), 5-FU 400 mg m(-2), LV 400 mg m(-2) on day 1, 5-FU 2400 mg m(-2) over 48 h and erlotinib 150 mg PO daily. Treatment was repeated every 14 days. The primary objective was response rate (RR), secondary objectives include toxicity, progression-free survival (PFS), overall survival (OS) and to correlate clinical outcome with expression patterns and molecular alterations in the epidermal growth factor receptor-dependent pathways.

RESULTS

A total of 33 patients were treated and evaluable: there were two complete responses, 15 partial responses for an objective RR of 51.5% (95% CI, 34.5-68.6%). Median PFS was 5.5 months (95% CI, 3.1-7.5 months) and median OS was 11.0 months (95% CI, 8.0-17.4 months). The most common grade 3-4 toxicities were: diarrhoea (24%), nausea/vomiting (11%), skin rash (8%) and peripheral neuropathy (8%). The frequency of alterations was KRAS mutations (8%), EGFR mutations (0%) and HER2 amplification (19%).

CONCLUSION

In patients with Eso/GEJ adenocarcinoma, mFOLFOX6 and erlotinib is active, has an acceptable toxicity profile and FOLFOX ± erlotinib could be considered for further development.

A phase II trial of gefitinib for recurrent or metastatic cancer of the esophagus or gastroesophageal junction

BACKGROUND

Conventional chemotherapeutic agents are of limited benefit in patients with recurrent or metastatic cancer of the esophagus or gastroesophageal junction (GEJ). We report results from a phase II trial in this population using gefitinib, an oral epidermal growth factor receptor inhibitor.

PATIENTS AND METHODS

Eligibility required a diagnosis of esophageal or GEJ adenocarcinoma or squamous cell carcinoma, which was either metastatic or recurrent and incurable after initial therapy. No more than one prior chemotherapy regimen was permitted. Treatment consisted of gefitinib 250 mg daily for a minimum of 8 weeks.

RESULTS

Between April 2003 and January 2010, 58 patients, including 18 who were chemotherapy-naïve, were entered into this trial. Toxicity was modest, although most experienced grade 1-2 diarrhea and/or skin rash. There were 4 partial responders (7%) and 10 patients with stable disease (17%). The clinical benefit (partial response and stable disease) lasted for a median 6.1 months. Median survival for all patients was 5.5 months with survival projections at 1-year of 24.6% and at 2-years of 12.5%.

CONCLUSION

Gefitinib was well tolerated but of limited efficacy in patients with recurrent or metastatic esophageal or GEJ cancer. Further study of this or similar agents will require better patient selection.

Biweekly cetuximab and irinotecan as second-line therapy in patients with gastro-esophageal cancer previously treated with platinum

BACKGROUND

Until recently there has been no proven second-line therapy for patients with advanced gastro-esophageal cancer (GEC). Since 2004, Denmark has had a national health program where non-proven therapy can be offered to patients with advanced cancer, after approval by an expert panel appointed by the National Board of Health. This program has accelerated the introduction and implementation of new therapies in Denmark. Inspired by therapy in metastatic colorectal cancer, a combination of cetuximab and irinotecan (Cetiri) was chosen for second-line therapy in GEC patients. We report our experience with Cetiri as second-line therapy in patients with GEC.

METHODS

All patients had histologically confirmed GEC and all patients had progressive disease during or after first-line platinum-containing chemotherapy. The patients received cetuximab 500 mg/m(2) on day 1 and irinotecan 180 mg/m(2) on day 1 every 2nd week until progression or unacceptable toxicity. Toxicity was prospectively evaluated according to the National Cancer Institute Common Terminology Criteria for Adverse Events (NCI-CTCAE) version 3.0.

RESULTS

From December 2007 to February 2009, 50 consecutive patients received Cetiri as second-line therapy. Median performance status (PS) was 1. The median number of courses was seven. Seven patients (14%) had a partial response. Median progression-free survival (PFS) was 3.3 months and overall survival (OS) was 5.5 months; two patients are still alive without progressive disease. Major toxicities were: diarrhea (8%), fatigue (10%), neutropenia (16%), and febrile neutropenia (2%).

CONCLUSION

Cetiri every two weeks is a convenient and well-tolerated second-line regimen in GEC patients. A promising effect was seen in patients with PS 0-1 and in patients who developed a rash.

Targeting key signalling pathways in oesophageal adenocarcinoma: A reality for personalised medicine?

Cancer treatments are rapidly changing. Curative treatment for oesophageal adenocarcinoma currently involves surgery and cytotoxic chemotherapy or chemoradiotherapy. Outcomes for both regimes are generally poor as a result of tumor recurrence. We have reviewed the key signalling pathways associated with oesophageal adenocarcinomas and discussed the recent trials of novel agents that attempt to target these pathways. There are many trials underway with the aim of improving survival in oesophageal cancer. Currently, phase 2 and 3 trials are focused on MAP kinase inhibition, either through inhibition of growth factor receptors or signal transducer proteins. In order to avoid tumor resistance, it appears to be clear that targeted therapy will be needed to combat the multiple signalling pathways that are in operation in oesophageal adenocarcinomas. This may be achievable in the future with the advent of gene signatures and a combinatorial approach.

Anti-HER agents in gastric cancer: from bench to bedside

Despite some advances in the past few years, the search for effective treatment modalities for advanced gastric and gastro-esophageal junction cancer is far from over. Available data clearly demonstrate that the development of new drugs will have little, if any, chance of success if it is not guided by in-depth knowledge of disease biology. However, using biologic agents to target key molecular pathways, such as those regulated by human epidermal growth factor receptor (HER) family members, may be effective. Indeed, the positive results achieved by the anti-HER2 agent trastuzumab in a phase III trial in HER2-positive patients support this approach. Many new anti-HER molecules are now under evaluation for the treatment of gastric and gastro-esophageal junction cancer, but so far attempts to identify reliable predictive factors from phase I and II trials have produced inconclusive results. In addition, large phase III trials are still being conducted in molecularly unselected populations. Refining patient selection is essential to maximize the benefit of targeted agents, to avoid significant toxicities and for the development of alternative therapeutic approaches in patients who have nonresponsive disease.

An open-label, multicentre biomarker-oriented AIO phase II trial of sunitinib for patients with chemo-refractory advanced gastric cancer

BACKGROUND

Sunitinib monotherapy in pretreated patients with advanced gastric cancer (AGC) was investigated. Preplanned analyses of tumour biomarkers on treatment outcome were performed.

PATIENTS AND METHODS

Patients received sunitinib 50mg/day for 4 weeks with 2 weeks rest until disease progression or unacceptable toxicity. The primary end-point was objective response rate (ORR). Secondary end-points included progression-free survival (PFS), overall survival (OS) and safety.

RESULTS

Fifty-two patients were enrolled and treated (safety population, SP). In the intention to treat population (n=51); the ORR was 3.9%, median PFS was 1.28 months [95% CI, 1.18-1.90], median OS was 5.81 months [95% CI, 3.48-12.32], the estimated one-year survival rate was 23.7% [95%CI: 12.8-36.5]. In subgroup analyses, tumour VEGF-C expression compared with no expression was associated with significantly shorter median PFS (1.23 versus 2.86 months, logrank p=0.0119) but there was no difference in tumour control rate (p=0.142). In the SP, serious adverse events occurred in 26 patients, leading to 13 deaths, all sunitinib unrelated. Thirty-eight patients died from progressive disease, nine died <60 days after treatment start.

CONCLUSION

Sunitinib monotherapy was associated with limited tumour response and good/moderate tolerability in this setting.

Molecularly targeted therapy for gastric cancer: current status and future prospects

Gastric cancer remains the second leading cause of cancer death worldwide. Currently, chemotherapy is the mainstay of treatment for patients with metastatic gastric cancer. Although new chemotherapeutic regimens improved the survival of patients with advanced gastric cancer, the median survival in all randomized trials remains unsatisfactory. Novel treatment options are urgently needed to improve the outcome of patients with advanced gastric cancer. Understanding the molecular pathways that characterize cell growth, apoptosis, angiogenesis and invasion has enabled us to use new approaches to treat this disease in clinical situations. The aim of this review is to summarize the most recent publications on targeted therapies for advanced gastric cancer.

Targeting metastatic upper gastrointestinal adenocarcinomas

Upper gastrointestinal (GI) tumors, including adenocarcinoma of the esophagus, stomach, pancreas, and biliary tree, have traditionally been difficult to treat with cytotoxic chemotherapeutic agents. There has been little drug development success in treating these cancers over the last 20 years, perhaps a reflection of a combination of the aggressive biology of these tumors, the void in effective and specific drug development for these varied tumors, and the lack of properly designed, biologically-based clinical trials. Recently, so called "targeted agents" have risen to the forefront in the care of cancer patients and have made strong impacts in many areas of oncology, particularly gastrointestinal stromal tumors (GIST), colon, breast, and lung cancers. Unfortunately, slow progress has been made using such agents in upper GI tumors. However, more recently, trials in some tumor types have demonstrated gains in progression free survival and overall survival. In this review, we discuss the drugs and pathways that have been most successful in the treatment of upper GI tumors and present the relevant data supporting their use for each tumor site. Additionally, we will explore a few novel pathways that may prove effective in the treatment of upper GI malignancies in the near future.

Critical appraisal of trastuzumab in treatment of advanced stomach cancer

Advanced or metastatic gastric cancer constitutes the majority of patients in clinical practice. In North America, about 70% of cases are advanced or metastatic when diagnosed, which is higher than the 50% reported in Japan. This difference in presentation is reflected in 5-year overall survival, which is about 20% in North America and 40%-60% in Japan. Despite numerous efforts of randomized studies on advanced gastric cancer, no globally accepted standard regimen has yet been established. Systemic chemotherapy provides palliation and prolongs survival, but the prognosis remains poor. Several monotherapies and combined regimens are currently available and vary around the world. Additionally, several molecular targeting agents are under evaluation in international randomized studies. Human epidermal growth factor receptor-2 (HER-2) is overexpressed or amplified in approximately 22% of patients with gastric cancer. Trastuzumab, a recombinant humanized anti-HER-2 monoclonal antibody, is the first biological therapy that has showed a survival improvement by nearly three months (reduced risk of death by 26%). Therefore, trastuzumab in combination with cisplatin is a reasonable treatment option for patients with advanced gastric cancer who are HER-2 positive. This paper will focus on trastuzumab, its chemical and pharmacological characteristics, and the relevant efficacy, safety, and tolerability studies.

Targeted therapies for metastatic esophagogastric cancer

The prognosis and long-term survival for patients with metastatic esophagogastric cancer (EGC) is poor. Historically, the mainstay of treatment has been combination chemotherapy. More recently, a number of targeted therapies have been developed and are being studied with the goal of improving response rate and survival in patients with metastatic EGC. To date, the only targeted therapy which has been clinically approved is trastuzumab which targets the HER2/Neu oncogene. However, only a small group of patients with EGCs are HER2 amplified, and there are other important targets/pathways which play a role in the development of these cancers that are currently being studied. With the identification of these other clinically relevant pathways, it is anticipated that several other therapies will be approved in the future.

Cetuximab enhances the activities of irinotecan on gastric cancer cell lines through downregulating the EGFR pathway upregulated by irinotecan

PURPOSE : Treatment effects of advanced gastric cancer (AGC) are unsatisfactory, and novel therapeutic approaches are much needed. The epidermal growth factor receptor (EGFR) monoclonal antibody cetuximab inhibits the growth of several human cancer cells but has been tested rarely for the treatment of GC. The synergy between cetuximab and irinotecan has been reported in colorectal cancer, but the mechanisms are still not fully clarified. Consequently, we hypothesized cetuximab/irinotecan combination should enhance the antitumor activity of irinotecan in GC cells. METHODS : The in vitro antiproliferative, pro-apoptotic, cell cycle arrest effects and induction of senescence were examined in SGC-7901 and MKN-45 GC cell lines. The effects of cetuximab or irinotecan as single agents or the combination on the expression of p53, p16, and EGFR signaling pathways were also studied. RESULTS : The study revealed that cetuximab alone did not show any antiproliferative, pro-apoptotic, cell cycle arrest or cellular senescence effect on GC cells but when combined with irinotecan synergistically inhibits GC cell proliferation and induces apoptosis and G2/M phase arrest. Irinotecan increases phosphorylation of EGFR, MAPK, and AKT and decreases the expression of P27(Kip1), which could be all abrogated by its combination with cetuximab. The combination could also inhibit the expression of Cyclin D1 and phosphorylated mTOR while had no impact on p53, p16, PTEN, and HIF-1alpha. CONCLUSIONS : Cetuximab enhances the activities of irinotecan on GC cells via the downregulation of the EGFR pathway upregulated by irinotecan. Combination therapy with cetuximab and irinotecan, a novel therapeutic approach, warrants further study in GC.

Low-dose taxotere enhances the ability of sorafenib to induce apoptosis in gastric cancer models

Despite the low efficacy of conventional antitumour drugs, chemotherapy remains an essential tool in controlling advanced gastric and oesophageal cancers. We aimed to provide a biological rationale based on the sorafenib-taxotere interaction for the clinical treatment of gastric cancer. In vitro experiments were performed on four human gastric cancer cell lines (GK2, AKG, KKP and NCI-N87). Cytotoxicity was evaluated by sulforhodamine B (SRB) assay, cell cycle perturbations, apoptosis and mitotic catastrophe were assessed by flow cytometric and microscopic analyses, and protein expression was studied by Western blot. In the in vivo experiments, nude mice xenografted with the most resistant line were treated with sorafenib and docetaxel singly or in association. Sorafenib inhibited cell growth (IG(50) values ranged from 3.4 to 8.1 μM) and caused down-regulation of MAP-K/ERK phosphorylation and of mcl-1 and p-bad expression after a 48-hr exposure. Apoptosis induction was associated with caspase-3 and -9 activation and mitochondrial membrane depolarization. The drug combination enhanced apoptosis (up to 80%) and produced a synergistic interaction when low doses of the taxane preceded administration of the antityrosine kinase. This synergism was probably due to the induction of an anomalous multidiploid G0-G1 peak and to consequent mitotic catastrophe, which increased sensitivity to sorafenib. Consistent with in vitro results, the docetaxel-sorafenib sequence exhibited high therapeutic efficacy in NCI-N87 mouse xenografts producing tumour weight inhibition (> 65%), tumour growth delay (up to 25 days) and increased mouse survival (30%). Our findings suggest the potential clinical usefulness of treatment with sorafenib and docetaxel for advanced gastric cancer.

Oncogenic mutations in gastric cancer with microsatellite instability

AIM

Mitogen-activated protein kinase (MAPK) cascade and phosphatidylinositol 3-kinase (PI3K) survival pathways are frequently activated in the progression of gastrointestinal malignancies. In this study, we aimed to determine the frequency of gene mutations in members of these pathways--Epithelial Growth Factor Receptor (EGFR), KRAS, BRAF, PIK3CA and MLK3 in a series of 63 gastric carcinomas with high levels of microsatellite instability (MSI).

METHODS

Gene mutation analysis was performed by PCR amplification followed by direct sequencing. In selected tumour cases, EGFR expression was evaluated by immunohistochemistry. Association studies between molecular data and clinicopathologic characteristics were performed.

RESULTS

Mutations in EGFR (3'-untranslated region [UTR] polyA repeat), KRAS, PIK3CA and MLK3 genes occurred in 30 (47.6%), 11 (17.5%), 9 (14.3%) and 2 (3.2%) of the MSI gastric cancer (GC) cases, respectively. No BRAF or EGFR hotspot mutations were identified. Overall, mutations in at least one of these genes were found in 55.6% (35/63) of gastric carcinomas. From those mutant cases 40.0% (14/35) of them had concomitant gene mutations, always involving EGFR polyA deletions. Interestingly, we observed significant associations between oncogenic mutations and female gender (p = 0.046) old age of diagnosis (p = 0.001) and intestinal subtype (p = 0.043).

CONCLUSION

Our results show that MSI gastric carcinoma frequently shows activation of EGFR-MAPK and PI3K pathways. Within all alterations found, deletions of the A13 repeats of EGFR were common, suggesting this molecular event as an important biomarker for stratification of GC patients for treatment with EGFR inhibitors.

A multicenter phase II trial of single-agent cetuximab in advanced esophageal and gastric adenocarcinoma

BACKGROUND

Epidermal growth factor receptor (EGFR) is overexpressed in a significant proportion of esophageal and gastric carcinomas. Although previous studies have examined tyrosine kinase inhibitors of EGFR, there remains limited data regarding the role of EGFR-directed monoclonal antibody therapy in these malignancies. We carried out a multi-institutional phase II study of cetuximab, a monoclonal antibody against EGFR, in patients with unresectable or metastatic esophageal or gastric adenocarcinoma.

PATIENTS AND METHODS

Thirty-five patients with previously treated metastatic esophageal or gastric adenocarcinoma were treated with weekly cetuximab, at an initial dose of 400 mg/m(2) followed by weekly infusions at 250 mg/m(2). Patients were followed for toxicity, treatment response, and survival.

RESULTS

Treatment with cetuximab was well tolerated; no patients were taken off study due to drug-related adverse events. One (3%) partial treatment response was noted. Two (6%) patients had stable disease after 2 months of treatment. Median progression-free survival and overall survival were 1.6 and 3.1 months, respectively.

CONCLUSION

Although well tolerated, cetuximab administered as a single agent had minimal clinical activity in patients with metastatic esophageal and gastric adenocarcinoma. Ongoing studies of EGFR inhibitors in combination with other agents may define a role for these agents in the treatment of esophageal and gastric cancer.

Efficacy of irinotecan in combination with 5-fluorouracil (FOLFIRI) for metastatic gastric or gastroesophageal junction adenocarcinomas (MGA) treatment

OBJECTIVES

The most commonly used schedules are 5-FU in combination with CDDP with or without epirubicin (ECF) or docetaxel (TCF) in treatment of MGA patients (pts), independently of HER status. We evaluated the efficacy of FOLFIRI regimen in a large retrospective series of MGA pts.

METHODS

Two hundred and twelve pts from 13 French centers were treated with at least one cycle of FOLFIRI (irinotecan 180 mg/m2 intravenous (i.v.) over 90 minutes on day 1 with folinic acid (FA) 400mg/m2 i.v. over two hours followed by 5-FU 400mg/m2 i.v. bolus then 5- FU 2400 mg/m2 continuous infusion over 46 hours on day 1, repeated every 14 days). Primary tumour sites were 120 (58%) stomach and 92 (42%) gastroesophageal junction. FOLFIRI was administered as first-line in 137 (65%) pts and as later-line in 75 (35%) pts for MGA.

RESULTS

There was no difference between chemonaive and not chemonaive pts treated as firstline in terms of response rate 37% (95% CI: 25-50) vs 44% (95% CI: 21-69), median PFS, 6.7 (95% CI: 5.5-9.9) vs 5.3 months (95% CI: 3.6-6.9) (P = 0.25), and OS, 13.1 (95% CI: 11.7-18.7) vs 8.8 months (95% CI: 7.3—15.6) (P = 0.19), respectively. There was no difference between pts treated as second or later-line in terms of response rate 20% (95% CI: 8-39) vs 22% (95% CI: 6-48), median PFS, four months (95% CI: 2.8-5.4) vs 3.5 months (95% CI: 2.3-4.5) (P = 0.56), and OS, 10.4 months (95% CI: 5.4-14.4) vs 5.3 months (95% CI: 3.5-11.3) (P = 0.58), respectively. The global grade 3-4 toxicities were: diarrhea 11%, vomiting 9%, neutropenia 18%, febril neutropenia 4% (one toxic death).

CONCLUSIONS

This retrospective study confirms the activity and good tolerance of FOLFIRI regimen in MGA as first-line as well as later-line.

Esophageal adenocarcinoma: treatment modalities in the era of targeted therapy

Esophageal adenocarcinoma is an aggressive malignancy with a poor outcome, and its incidence continues to rise at an alarming rate. Current treatment strategies combining chemotherapy, radiation, and surgery are plagued with high rates of recurrence and metastasis. Multiple molecular pathways including the epidermal growth factor receptor, vascular endothelial growth factor, v-erb-b2 erythroblastic leukemia viral oncogene homolog (ERBB2), and Aurora kinase pathways are activated in many esophageal adenocarcinomas. In many cases, these pathways have critical roles in tumor progression. Research on the mechanisms by which these pathways contribute to disease progression has resulted in numerous biologic agents and small molecules with the potential to improve outcome. The promise of targeted therapy and personalized medicine in improving the clinical outcome is now closer than it has ever been.

Cetuximab with irinotecan, folinic acid and 5-fluorouracil as first-line treatment in advanced gastroesophageal cancer: a prospective multi-center biomarker-oriented phase II study

BACKGROUND

Cetuximab plus irinotecan/folinic acid/5-fluorouracil (5-FU) (IF) was evaluated as first-line treatment of patients with advanced gastric cancer and gastroesophageal junction tumors. Preplanned analyses of the influence of tumor biomarkers on treatment outcome were carried out.

PATIENTS AND METHODS

Patients received weekly cetuximab (400 mg/m(2) on day 1, subsequently 250 mg/m(2)) plus irinotecan (80 mg/m(2)) and a 24-hour continuous infusion of folinic acid (200 mg/m(2)) and 5-FU (1500 mg/m(2)) on days 1, 8, 15, 22, 29 and 36 of a 50-day cycle, until progressive disease (PD).

RESULTS

The most common grade 3/4 toxic effects in 49 patients were diarrhea (15%) and skin toxic effects (14%). In 48 assessable patients, the overall response rate was 46% and disease control rate was 79%. Median progression-free survival (PFS) and overall survival (OS) was 9.0 months [95% confidence interval (CI) 7.1-15.6] and 16.5 months (95% CI 11.7-30.1), respectively. Tumor response was more common than nonresponse in epidermal growth factor receptor-expressing tumors (P = 0.041). Tumor PTEN expression was associated with longer PFS (P = 0.035) and OS (P = 0.0127) than no PTEN expression.

CONCLUSION

Cetuximab plus IF was well tolerated and efficacy data were encouraging. This treatment combination and the role of selected biomarkers are under investigation in the ongoing phase III EXPAND trial.

DNA polymerase η protein expression predicts treatment response and survival of metastatic gastric adenocarcinoma patients treated with oxaliplatin-based chemotherapy

Background

DNA polymerase η (pol η) is capable of bypassing DNA adducts produced by cisplatin or oxaliplatin and is associated with cellular tolerance to platinum. Previous studies showed that defective pol η resulted in enhanced cisplatin or oxaliplatin sensitivity in some cell lines. The purpose of the present study was to investigate the role of pol η protein expression in metastatic gastric adenocarcinoma.

Methods

Four gastric adenocarcinoma cell lines were chosen to explore the relationship between pol η protein expression and oxaliplatin sensitivity by western blotting and MTT assay. Eighty metastatic gastric adenocarcinoma patients treated with FOLFOX or XELOX regimen as first-line chemotherapy were analyzed, corresponding pretreatment formalin-fixed paraffin-embedded tumor tissues were used to detect pol η protein expression by immunohistochemistry. Relationship between pol η protein expression and clinical features and outcome of these patients was analyzed.

Results

A positive linear relationship between pol η protein expression and 48 h IC50 values of oxaliplatin in four gastric cancer cell lines was observed. Positivity of pol η protein expression was strongly associated with poor treatment response, as well as shorter survival at both univariate (8 versus 14 months; P < 0.001) and multivariate (hazard ratio, 4.555; 95% confidence interval, 2.461-8.429; P < 0.001) analysis in eighty metastatic gastric adenocarcinoma patients.

Conclusions

Our study indicates that polη is a predictive factor of treatment response and survival of metastatic gastric adenocarcinoma patients treated with FOLFOX or XELOX as first-line chemotherapy. Therefore confirming the value of polη in studies with prospective design is mandatory.

Effects of valproic acid on the cell cycle and apoptosis through acetylation of histone and tubulin in a scirrhous gastric cancer cell line

BACKGROUND

Management of peritoneal dissemination is the most critical problem in gastric cancer. This study was performed to investigate the inhibitory effects of valproic acid (VPA) on a highly peritoneal-seeding cell line of human scirrhous gastric cancer, OCUM-2MD3, and to explore the mechanism and the potential of VPA.

METHODS

The effects of VPA on the growth of OCUM-2MD3 cells were assessed by MTT assay. In addition, paclitaxel (PTX) was combined with VPA to evaluate their synergistic effects. HDAC1 and HDAC2 expression were evaluated by western blotting in OCUM-2MD3 cells and other gastric cancer cell lines (TMK-1, MKN-28). The acetylation status of histone H3 and α-tubulin after exposure to VPA were analyzed by western blotting. The activities of cell cycle regulatory proteins and apoptosis-modulating proteins were also examined by western blotting. The effects of VPA in vivo were evaluated in a xenograft model, and apoptotic activity was assessed by TUNEL assay.

RESULTS

OCUM-2MD3 cells showed high levels of HDAC1 and HDAC2 expression compared with TMK-1 and MKN-28. The concentration of VPA required for significant inhibition of cell viability (P < 0.05) was 5 mM at 24 h and 0.5 mM at 48 h and 72 h. The inhibition of VPA with PTX showed dose-dependent and combinatorial effects. VPA increased acetyl-histone H3, acetyl-α-tubulin, and p21WAF1 levels accompanied by upregulation of p27, caspase 3, and caspase 9, and downregulation of bcl-2, cyclin D1, and survivin. In the xenograft model experiment, the mean tumor volume of the VPA-treated group was significantly reduced by 36.4%, compared with that of the control group at 4 weeks after treatment (P < 0.01). The apoptotic index was significantly higher in the VPA-treated group (42.3% ± 3.5%) than in the control group (7.7% ± 2.5%) (P < 0.001).

CONCLUSIONS

VPA induced dynamic modulation of histone H3 and α-tubulin acetylation in relation with the anticancer effect and the enhancement of PTX in the OCUM-2MD3 cell line. Therefore, VPA in combination with PTX is expected to be a promising therapy for peritoneal dissemination of scirrhous gastric cancer.

A phase 2 trial of erlotinib in patients with previously treated squamous cell and adenocarcinoma of the esophagus

BACKGROUND

Tyrosine kinase inhibitors (TKIs) of the epidermal growth factor receptor (EGFR) have activity in solid tumors. The authors evaluated an oral EGFR TKI, erlotinib, in patients with previously treated esophageal cancer.

METHODS

Thirty patients with measurable, metastatic cancer of the esophageal and gastroesophageal junction received 150 mg erlotinib daily. EGFR-negative tumors (6 patients; 20%) and EGFR-over expressing tumors (24 patients; 80%) were treated. Most patients were men (70%) with adenocarcinoma (57%) and had received previous chemotherapy (97%).

RESULTS

Two partial responses were observe d in the EGFR-positive cohort (2 of 24 patients; 8%), and no responses were observed in the EGFR-negative cohort (0 of 6 patients). Reponses were limited to patients who had squamous cell carcinoma (2 of 13 patients; 15%; response duration, 5.5-7 months). The time to tumor progression was longer in patients who had squamous cell carcinoma (3.3 months; range, 1-24 months) compared with patients who had adenocarcinoma (1.6 months; range, 1-6 months; P = .026). Therapy was tolerable with the expected toxicity of skin rash (grade 1-2, 67%; grade 3, 10%).

CONCLUSIONS

Erlotinib had limited activity in patients with esophageal cancer, and responses and some protracted stable disease were observed in those with squamous cell carcinoma. Efficacy according to EGFR status could not be assessed given the rarity of EGFR-negative tumors. The current results indicated that further evaluation of this agent in squamous cell carcinoma is warranted. Cancer 2011. © 2010 American Cancer Society.

Phase I dose-finding study of sorafenib in combination with capecitabine and cisplatin as a first-line treatment in patients with advanced gastric cancer

BACKGROUND

To define maximum-tolerated dose (MTD), dose-limiting toxicities (DLTs), and preliminary efficacy of sorafenib plus capecitabine/cisplatin in advanced gastric cancer (AGC) patients.

METHODS

Four dose-level combinations were tested in a standard 3 + 3 dose escalation design. Level 1: sorafenib 400 mg/d, capecitabine 1,600 mg/m(2)/d, cisplatin 80 mg/m(2). Level 2: sorafenib 800 mg/d, capecitabine 1,600 mg/m(2)/d, cisplatin 80 mg/m(2). Level 3: sorafenib 800 mg/d, capecitabine 2,000 mg/m(2)/d, cisplatin 80 mg/m(2). Level 1A: sorafenib 800 mg/d, capecitabine 1,600 mg/m(2)/d, cisplatin 60 mg/m(2).

RESULTS

There were 1 DLT at Level 2, and 2 DLTs at Level 3 (Level 3 was MTD). Since the relative dose intensity (RDI) of sorafenib and capecitabine could not be maintained at Level 2, Level 1A was newly investigated. As no DLT was observed and RDI remained above 80%, Level 1A is the recommended dose for the next clinical trial. Objective response rate was 62.5% (10 of 16 patients, 95% CI; 38.8-86.2%). Median progression-free survival and overall survival were 10.0 months (95% CI; 7.4-13.8) and 14.7 months (95% CI; 12.0-20.0), respectively.

CONCLUSIONS

Sorafenib 400 mg bid daily, capecitabine 800 mg/m(2) bid (days 1-14), and cisplatin 60 mg/m(2) (day 1) is recommended for further development in AGC.

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.

Cetuximab as second-line therapy in patients with metastatic esophageal adenocarcinoma: a phase II Southwest Oncology Group Study (S0415)

INTRODUCTION

Esophageal adenocarcinomas commonly express the epidermal growth factor receptor. This trial assessed the 6-month overall survival probability in metastatic esophageal cancer patients treated with cetuximab as second-line therapy.

METHODS

This was a multicenter, open-label phase II study of single-agent cetuximab for metastatic esophageal adenocarcinoma patients who failed one prior chemotherapy regimen. Adequate organ function and Zubrod performance status of 0 to 2 were required. Patients received cetuximab 400 mg/m intravenously (IV) on week 1 and 250 mg/m IV weekly thereafter. The primary objective was to determine 6-month overall survival. Secondary end points included progression-free survival, response rate, and toxicity. Tumor tissue was collected for correlative studies.

RESULTS

Sixty-three patients were registered, with eight ineligible or never treated. Fifty-five eligible patients (49 men, 6 women; median age = 61.2 years [range, 30.7-88.5]) were enrolled. Twenty patients survived more than 6 months for a 6-month overall survival rate of 36% (95% confidence interval [CI]: 24-50%). The median overall survival was 4.0 months (95% CI: 3.2-5.9). Median progression-free survival was 1.8 months (95% CI: 1.7-1.9). One partial response and two unconfirmed partial responses were observed. Two patients experienced grade 4 fatigue. There was one treatment-related death due to pneumonitis. Germline polymorphisms of epidermal growth factor receptor, epidermal growth factor, interleukin (IL)-8, cyclooxygenase (COX)-2, vascular epidermal growth factor receptor (VEGF), CCND1, neuropilin 1 (NRP1), and K-ras mutational status were not associated with response or survival.

CONCLUSIONS

The 6-month overall survival rate of 36% observed on this study failed to meet the primary survival objective. Thus, cetuximab alone cannot be recommended in the second-line treatment of metastatic esophageal cancer.

New insights into the mechanisms of gastric cancer multidrug resistance and future perspectives

Gastric cancer is still the second leading cause of cancer death worldwide. Chemotherapy is one of the major treatment options for advanced gastric cancer. The efficacy of chemotherapy for gastric cancer is poor due to insensitivity and the development of multidrug resistance (MDR). Gastric cancer MDR involves a large number of molecules and complex mechanisms. Classical drug-resistant molecules, such as P-glycoprotein/ABCB1 and MRP1/ABCC1, have been found to play important roles in mediating MDR in some gastric cancers. In recent years, new molecules and mechanisms have been found to be associated with the development of gastric cancer MDR and might provide new targets for tackling gastric cancer MDR. Combined use of molecularly targeted therapy with chemotherapy may offer improved outcomes for gastric cancer patients and might provide new threads of hope for gastric cancer treatment.

Neoadjuvant treatment of esophageal cancer

The management of esophageal cancer has been evolving over the past 30 years. In the United States, multimodality treatment combining chemotherapy and radiotherapy (RT) prior to surgical resection has come to be accepted by many as the standard of care, although debate about its overall effect on survival still exists, and rightfully so. Despite recent improvements in detection and treatment, the overall survival of patients with esophageal cancer remains lower than most solid tumors, which highlights why further advances are so desperately needed. The aim of this article is to provide a complete review of the history of esophageal cancer treatment with the addition of chemotherapy, RT, and more recently, targeted agents to the surgical management of resectable disease.

Epirubicin, oxaliplatin, and capecitabine with or without panitumumab for advanced esophagogastric cancer: dose-finding study for the prospective multicenter, randomized, phase II/III REAL-3 trial

PURPOSE

Epirubicin, oxaliplatin, and capecitabine (EOC) is a standard treatment in advanced esophagogastric cancer. Panitumumab (P) is a fully human, immunoglobulin G2 monoclonal antibody targeting epidermal growth factor receptor. Randomized Trial of EOC +/- Panitumumab for Advanced and Locally Advanced Esophagogastric Cancer (REAL-3) will evaluate whether the addition of P to EOC improves survival in patients with advanced esophagogastric adenocarcinoma and undifferentiated carcinoma.

PATIENTS AND METHODS

The original design of REAL-3 added P 9 mg/kg to the standard dose of EOC (dose level [DL] + 1). Due to toxicity, a dose de-escalation was made to EOC + P DL-1 (epirubicin 50 mg/m(2), oxaliplatin130 mg/m(2), capecitabine 1,000 mg/m(2)/d + P 9 mg/kg every 3 weeks). After additional toxicity was observed, the study was amended to include two additional EOC + P dose levels. Using a 3 + 3 design, dose-limiting toxicities (DLTs) were assessed weekly during cycle 1. Patients were randomly assigned 1:1 to EOC +/- P.

RESULTS

Between July 2008 and October 2009, 29 patients were randomly selected for standard-dose EOC (n = 13) or EOC + P (n = 16). Five patients were treated at DL + 1, with grade 3 diarrhea in four of five patients by cycle 4. At DL-1, one patient had grade 3 diarrhea and grade 5 infection. Three patients were treated at DL-3, and then six were treated at DL-2, without DLTs.

CONCLUSION

The recommended dose for EOC + P is epirubicin 50 mg/m(2), oxaliplatin 100 mg/m(2), capecitabine 1,000 mg/m(2)/d, and P 9 mg/kg every 3 weeks. This dose has been selected for the ongoing phase II/III REAL-3 study.

Novel perspectives for the treatment of gastric cancer: from a global approach to a personalized strategy

Although recent advances have been made, surgery still remains the mainstay of any curative treatment for gastric cancer patients, with radical gastrectomy representing the procedure of choice. However, patients with locally advanced disease show high rates of locoregional or distant recurrence even after potentially curative resections. According to global results presented in the setting of locally advanced resectable gastric carcinoma, perioperative chemotherapy may be considered a valuable option. On the other hand, clinical trials for advanced gastric cancer seem to suggest that a limit in efficacy has been reached for standard chemotherapy. Interesting data are expected from the development of targeted agents that, similarly to other cancer sites, showed appealing results in gastric cancer as well. Along with new effective therapeutic opportunities, better clinical and molecularly driven patient selection will represent the cornerstone of the global care for these patients.

Recent advances in chemotherapy for advanced gastric cancer

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.

A phase II study of irinotecan with biweekly, low dose leucovorin and bolus and continuous infusion 5-fluorouracil (modified FOLFIRI) as first line therapy for patients with recurrent or metastatic gastric cancer

BACKGROUND

To determine the activity and toxicities of a low-dose leucovorin plus 5-fluorouracil (5-FU) regimen, combined with irinotecan and administered every 2 weeks (modified FOLFIRI), as a first-line therapy for patients with advanced gastric cancer.

METHOD

Patients were treated with cycles of 150 mg/m irinotecan on day 1 plus 50 mg of LV, followed by a 400 mg/m 5-FU bolus and a 22-hour continuous infusion of 600 mg/m 5-FU on days 1 and 2.

RESULTS

The median patient age was 55 years (range, 29-75 years), and 77% (34/44) of the patients had a performance status (Eastern Cooperative Oncology Group) of 0 or 1. Of the 44 patients evaluated for their tumor response, 3 patients (6.8%) and 14 patients (31.8%) achieved a complete and partial response, respectively, with an overall response rate of 38.6% (95% confidence interval, 23.7%-53.6%). 13 patients (29.6%) evidenced a stable disease, and 14 patients (31.8%) progressed during the course of the treatment. The median time to progression and overall survival time were 4.9 months (range, 0.9-22.8 months) and 10.3 months (range, 1.2-29.0 months) from the start of the chemotherapy, respectively. A total of 293 cycles were assessed for toxicity. The major hematologic toxicities included grade 1 to 2 anemia (27.6%), neutropenia (48.8%), and grade 3 to 4 neutropenia (12.6%). There were 7 cycles of neutropenic fever. Nonhematological toxicities were observed grade 3 vomiting (6.8%), grade 3 diarrhea (4.5%), and grade 3 mucositis (2.3%). We noted no treatment-related deaths.

CONCLUSIONS

The modified FOLFIRI regimen-lowering of irinotecan and LV doses-is a safe and feasible regimen as a first-line therapy for patients with recurrent or metastatic gastric cancer.

Matuzumab plus epirubicin, cisplatin and capecitabine (ECX) compared with epirubicin, cisplatin and capecitabine alone as first-line treatment in patients with advanced oesophago-gastric cancer: a randomised, multicentre open-label phase II study

BACKGROUND

Clinical data showed promising antitumour activity with feasible tolerability for matuzumab plus epirubicin, cisplatin and capecitabine (ECX) chemotherapy in untreated advanced oesophago-gastric (OG) cancer. The aim was to evaluate the efficacy of matuzumab plus ECX versus ECX alone.

PATIENTS AND METHODS

In this multicentre, randomised open-label phase II study, 72 patients with metastatic OG cancer were randomly assigned to either 800 mg matuzumab weekly plus epirubicin 50 mg/m², cisplatin 60 mg/m² on day 1 and capecitabine 1250 mg/m² daily in a 21-day cycle (ECX) or the same ECX regimen alone. The primary end point was objective response. Secondary end points included progression-free survival (PFS), overall survival (OS), quality of life, safety and tolerability.

RESULTS

Following random assignment, 35 patients (median age 59 years) received ECX/matuzumab and 36 patients (median age 64 years) ECX. The addition of matuzumab to ECX did not improve objective response: 31% for ECX/matuzumab [95% confidence interval (CI) 17-49] compared with 58% for the ECX arm (95% CI 41-74) P = 0.994 (one sided). There was no significant difference in median PFS: 4.8 months (95% CI 2.9-8.1) for ECX/matuzumab versus 7.1 months (95% CI 4.4-8.5) for ECX, or in median OS: 9.4 months (95% CI 7.5-16.2), compared with 12.2 months (95% CI 9.8-13.8 months). Grade 3/4 treatment-related toxicity was observed in 27 and 25 patients in the ECX/matuzumab and ECX groups, respectively.

CONCLUSION

Matuzumab 800 mg weekly combined with ECX chemotherapy does not increase response or survival for patients with advanced OG cancer. Therefore, ECX/matuzumab should not be examined further in phase III trials.

Dysregulation of cellular signaling in gastric cancer

The pathogenesis of gastric cancer is complex and related to multiple factors. Dysregulation of intracellular signaling pathways represents a common pathogenic mechanism and may be amenable to drug targeting. Multiple well-established oncogenic pathways, such as those mediated by cell cycle regulators, nuclear factor-kappaB, cyclooxygenase-2 and epidermal growth factor receptor are implicated in gastric carcinogenesis. Emerging evidence also underscores the importance of signaling pathways involved in the developmental process, including transforming growth factor-beta/bone morphogenetic protein signaling, Wnt/beta-catenin signaling, Hedgehog signaling and Notch signaling. Understanding their biological significance will provide a rational basis for drug development. Their relative importance and cross-talk in gastric carcinogenesis, however, are still not completely understood and warrant further investigation.

Phase II study of sunitinib as second-line treatment for advanced gastric cancer

Purpose. This phase II, open-label, multicenter study assessed the oral, multitargeted, tyrosine kinase inhibitor sunitinib in patients with advanced gastric or gastroesophageal junction adenocarcinoma who had received prior chemotherapy. Experimental design. Patients received sunitinib 50 mg/day on Schedule 4/2 (4 weeks on treatment, followed by 2 weeks off treatment). The primary endpoint was objective response rate; secondary endpoints included clinical benefit rate, duration of response, progression-free survival (PFS), overall survival (OS), pharmacokinetics, pharmacodynamics, safety and tolerability, and quality of life. Results. Of 78 patients enrolled, most had gastric adenocarcinoma (93.6%) and metastatic disease (93.6%). All were evaluable for safety and efficacy. Two patients (2.6%) had partial responses and 25 patients (32.1%) had a best response of stable disease for ≥6 weeks. Median PFS was 2.3 months (95% confidence interval [CI], 1.6–2.6 months) and median OS was 6.8 months (95% CI, 4.4–9.6 months). Grade ≥3 thrombocytopenia and neutropenia were reported in 34.6% and 29.4% of patients, respectively, and the most common non-hematologic adverse events were fatigue, anorexia, nausea, diarrhea, and stomatitis. Pharmacokinetics of sunitinib and its active metabolite were consistent with previous reports. There were no marked associations between baseline soluble protein levels, or changes from baseline, and measures of clinical outcome. Conclusions. The progression-delaying effect and manageable toxicity observed with sunitinib in this study suggest that although single-agent sunitinib has insufficient clinical value as second-line treatment for advanced gastric cancer, its role in combination with chemotherapy merits further study.

Gastric carcinoma in China: Current status and future perspectives (Review)

Gastric cancer is one of the most frequently occurring cancers in China, with an estimated 380,000 new cases each year, accounting for more than 40% of the worldwide annual cancer incidence. There is geographical clustering of the distribution of gastric cancer in China, with most of the high-risk areas being rural. D2 resection is the standard lymphadenectomy for curative resection in China, but more extensive lymphadenectomy is conducted for selected patients. Perioperative chemotherapy, postoperative chemotherapy or chemoradiotherapy can be combined with surgery. It remains uncertain which option is best, but if surgery is insufficient, adjuvant chemoradiotherapy is recommended. In the palliative setting, although there is no standard first-line chemotherapy, regimens based on taxane, oxaliplatin or capecitabine, or the epirubicin, cisplatin, 5-fluorouracil regimen and its modifications are the most common options selected by Chinese oncologists. Several studies to evaluate target therapy are ongoing, but it is too early to draw any conclusions. However, the development of target therapy is likely to become a milestone in the treatment of gastric cancer.

Construction and characterization of a novel fusion protein MG7-scFv/SEB against gastric cancer

Antibody-targeted superantigen has been developed into a new strategy to treat many malignant tumors. In this study, for specific targeting to gastric cancer cell, superantigen SEB (Staphylococcal Enterotoxin B) was genetically fused to the single-chain variable fragment of gastric carcinoma-associated antibody MG7(MG7-scFv) that recognizes the MG7 antigen frequently expressed in gastric cancer cell. The recombinant MG7-scFv/SEB fusion proteins are expressed in E. coli as inclusion bodies, and the purified MG7-scFv/SEB retains high binding affinity with gastric cancer cell SGC-7901 (positive MG7 antigen expression). When incubated with effector cell-peripheral blood mononuclear cells (PBMCs), MG7-scFv/SEB could effectively inhibit the proliferation and induce apoptosis of SGC-7901. After being treated with MG7-scFv/SEB, PBMCs remarkably increased the production of Th1 cytokines (IFN-gamma, IL-2), and slightly increased the production of Th2 cytokines (IL-4, IL-10) in vitro. It was observed that gastric-tumor-bearing rats administrated with MG7-scFv/SEB showed more inflammatory cell infiltration, more significant tumor inhibition, and longer survival time than those of rats treated with SEB or NS (Normal Saline). The data indicated that MG7-scFv/SEB fusion protein could specifically target gastric cancer cell, enhance the activity of T cells and induce tumor cell apoptosis to exert the antitumor effect on gastric cancer.

Novel investigational drugs for gastric cancer

BACKGROUND

Gastric cancer still represents a leading cause of death worldwide. Several cytotoxic agents have demonstrated activity and combination regimens improve progression-free survival, overall survival and quality of life. Nevertheless, now there is no standard therapy for advanced gastric cancer patients.

OBJECTIVE

To evaluate the role of new investigational agents.

METHODS

We analysed Phase I, II and III studies that evaluated tailored drugs directed against the epidermal growth factor receptor (EGFR), the c-erbB2, the vascular endothelial growth factor (VEGF), the vascular endothelial growth factor receptor (VEGFR), the matrix metalloproteinases (MMP) and the mammalian target of rapamycin (mTOR).

CONCLUSION

Data from Phase II trials indicate the potential of improved efficacy of chemotherapy when administered in combination with bevacizumab and cetuximab. Trastuzumab results are ongoing, while marimastat has not obtained clinical developments even if it has demonstrated to be an active drug in this setting of patients.

Epidermal growth factor receptor intron 1 CA dinucleotide repeat polymorphism and survival of advanced gastric cancer patients treated with cetuximab plus modified FOLFOX6

Cetuximab is a monoclonal antibody targeting epidermal growth factor receptor (EGFR). The present study investigated the association between germline genetic polymorphisms and the treatment outcome of cetuximab plus modified leucovovin, fluorouracil, and oxaliplatin (FOLFOX)6 chemotherapy in advanced gastric cancer (AGC). DNA from peripheral blood mononuclear cells of 38 patients enrolled in a phase II study of cetuximab plus modified FOLFOX6 were analyzed for 16 polymorphisms in eight genes (EGFR, epidermal growth factor, transforming growth factor-alpha (TGFA), thymidylate synthase, excision repair cross-complementation group 1, Xeroderma pigmentosum group D, and fragment c gamma receptors (FCGR)2A and 3A). The EGFR intron 1 CA repeat polymorphism was associated with survival. Twenty-one patients had low repeats (sum of both alleles or=38). Patients with low CA repeats had longer progression-free survival (adjusted hazard ratio [HR] 0.42 [95% confidence interval [CI] 0.19-0.96], P = 0.040) and overall survival (adjusted HR 0.40 [95% CI 0.16-0.99], P = 0.048) compared with patients with high CA repeats. In addition, the tumor EGFR expression was higher in patients with a lower number of CA repeats. The association between the CA repeat status and survival was not found in a separate cohort of AGC patients (n = 68) treated only with modified FOLFOX6. These results suggest that the EGFR intron 1 CA repeat polymorphism could be a useful, predictive biomarker of cetuximab efficacy in AGC and merits further investigation in randomized studies.

Advanced gastric cancer--slow but steady progress

Progress in gastric cancer has been slow, but steady. Historically, patients commonly presented with significant disease related co-morbidity and received treatment of marginal benefit but unfortunately associated with significant toxicity. Today there is no universally accepted reference standard chemotherapy for this disease. However, there is reason for optimism. Meta-analyses of randomized trials have shown a benefit for first-line combination chemotherapy. Current three drug chemotherapy regimens remain toxic, though perhaps less so than previously, and can result in a small but significant survival advantage in carefully chosen patients. Incremental improvements have been observed in both treatment-related toxicity and survival after first-line therapy. More patients are candidates for chemotherapy beyond progression with first-line therapy and response rates with second-line regimens are similar to those seen in other solid tumor malignancies. Although there is no randomized data to support its use second-line treatment should be considered in appropriate patients. Even before the integration of targeted therapies in the treatment of gastric cancer, it was evident that survival for more than 2 years is possible in a subset of patients and large retrospective studies have highlighted clinicopathologic factors associated with improved survival. Presently, with the addition of targeted therapy, especially anti-angiogenic and anti-Her2 therapy, and a better understanding of the biology of the disease, perhaps a sense of optimism should indeed suppress the nihilism commonly associated with this disease.

Esophagogastric cancer: targeted agents

Because of the poor prognosis for patients with locally advanced and metastatic esophageal, gastroesophageal junction and gastric cancers, increasing attention has focused on the integration of targeted agents into current therapies. The molecular targets of these agents include epidermal growth factor receptor (EGFR), vascular endothelial growth factor (VEGF) or its receptor, cyclooxygenase-2 (COX-2), mammalian target of rapamycin (mTOR) and components and regulators of the cell cycle. In this review article, we briefly discuss pre-clinical data and the rationale for targeting these pathways and summarize the results of clinical trials to-date, including completed and ongoing phase III evaluations.

Docetaxel: its role in current and future treatments for advanced gastric cancer

A globally accepted standard chemotherapy remains undetermined in gastric cancer, but the recent introduction of active "new-generation agents" such as taxanes, irinotecan (CPT-11), oxaliplatin, S-1, and capecitabine, offers hope for markedly improving patient outcomes. Docetaxel, as well as the other new-generation agents, plays a key role in the development of the new-era chemotherapy, and the incorporation of taxanes has provided several regimens, such as docetaxel/cisplatin/5-fluorouracil (5-FU) (DCF), that could become standard treatment. The DCF regimen is now regarded as a standard treatment option in advanced gastric cancer in selected patients in good condition. Many institutions and cooperative groups continue to study a variety of docetaxel-based combinations with "new-generation cytotoxic agents" in various treatment settings, and recent attention has been focused on the incorporation of biological agents, such as cetuximab, bevacizumab, everolimus, and sunitinib, into docetaxel-containing combinations as another innovative approach. The ongoing clinical trials of a number of new regimens will clarify their clinical benefits in gastric cancer treatment. Along with the development of more active docetaxel combination regimens, the identification of predictive biomarkers for each regimen has been intensively studied recently. This review focuses on docetaxel as a key agent in gastric cancer chemotherapy, and discusses the role of this taxane in current and future treatments for advanced gastric cancer.

Advances in the pharmacological treatment of gastro-oesophageal cancer

Despite a sharp decline in the incidence of gastric cancer during the second half of the 20th century, this malignancy remains the second leading cause of cancer mortality in the world. The incidence and mortality rate of gastric cancer increase with age; at present, the median ages at diagnosis are 67 years for men and 72 years for women in the US. This article reviews and discusses current medical treatment options for both the general population and elderly gastric cancer patients. Management of localized gastric cancer has changed significantly over recent years. Adjuvant chemoradiation is not generally recommended outside the US. After decades of trials of adjuvant chemotherapy with inconclusive results, a significant survival benefit for perioperative combination chemotherapy - as compared with surgery alone - in patients with resectable or locally advanced gastro-oesophageal cancer was recently demonstrated in the UK MAGIC trial. A further large, randomized trial from Japan demonstrated a significant survival benefit for adjuvant chemotherapy with S-1 after D2 resection for gastric cancer. However, both trials are applicable only to the population in which the trials were conducted. Specific data on elderly patients are missing. For patients with metastatic disease, oral fluoropyrimidines, such as capecitabine, have been developed. In Asian patients, treatment with the oral fluoropyrimidine S-1 is safe and effective. Docetaxel, oxaliplatin and irinotecan have demonstrated activity against gastric cancer in appropriately designed, randomized, phase III trials and have increased the available treatment options significantly. In addition, according to preliminary data, trastuzumab in combination with chemotherapy has significantly improved activity when compared to chemotherapy alone in patients with human epidermal receptor (HER)-2-positive gastric and gastro-oesophageal cancers. Thus, therapeutic decisions in patients with advanced gastric cancer may be adapted to the molecular subtype and co-morbidities of the individual patient. Data from retrospective analyses suggest that oxaliplatin seems to be better tolerated than cisplatin in elderly patients.

Cetuximab plus oxaliplatin/leucovorin/5-fluorouracil in first-line metastatic gastric cancer: a phase II study of the Arbeitsgemeinschaft Internistische Onkologie (AIO)

BACKGROUND

Cetuximab enhances the efficacy of chemotherapy in several cancer types. This trial assessed the activity of cetuximab and chemotherapy in advanced gastric cancer.

METHODS

Patients with previously untreated, metastatic, gastric cancer received cetuximab 400 mg m(-2) at first infusion followed by weekly infusions of 250 mg m(-2) combined with FUFOX (oxaliplatin 50 mg m(-2), 5-FU 2000 mg m(-2), and DL-folinic acid 200 mg m(-2) d1, 8, 15 and 22 qd36). The primary endpoint was tumour response.

RESULTS

Overall, 52 patients were enrolled. The most common grade 3/4 toxicities were diarrhoea (33%), and skin toxicity (24%). Efficacy was evaluable in 46 patients who showed a response rate of 65% (CI 95%: 50-79%) including four complete responses. Time to progression (TTP) was 7.6 months (CI 95%: 5.0-10.1 months) and overall survival (OS) was 9.5 months (CI 95%: 7.9-11.1 months). Epidermal growth factor receptor (EGFR) was detectable in 60% of tumours but showed no correlation with treatment outcome. A KRAS mutation was found in only 1 of 32 (3%) tumour samples analysed.

CONCLUSION

Cetuximab plus FUFOX showed an interesting high response rate in metastatic gastric cancer. Cetuximab plus platinum-fluoropyrimidine chemotherapy is at present being investigated in a phase III randomised controlled trial.

Recommendations on current approach to gastric cancer

The management of gastric cancer has been updated by the Grupo Español de Tratamiento de Tumores Digestivos (TTD). A multidisciplinary approach is essential in these patients including a precise diagnosis and staging and correct nutritional evaluation. For resectable disease, surgical resection remains the treatment mainstay and both perioperatory chemotherapy and postoperatory chemo-radiotherapy are considered standard complementary treatments. In advanced disease chemotherapy should always be considered. There are different reference schemes (TCF, XC, ECF, EXC) and the therapeutic option has to be individualised. Recently a phase III trial has shown a significant improvement in overall survival when trastuzumab is added to cisplatin-capecitabine or cisplatin-5-fluorouracil in patients with HER2+ advanced gastric cancer. Currently, there are several ongoing clinical trials evaluating the role of other new drugs against cellular targets. It would be desirable to incorporate biomarker studies in these trials in order to identify the best treatment for each patient.