Apatinib for chemotherapy-refractory advanced metastatic gastric cancer: results from a randomized, placebo-controlled, parallel-arm, phase II trial

Apatinib: A novel receptor tyrosine kinase inhibitor for the treatment of gastric cancer

Metastatic gastric cancer is a lethal disease characterized by a very short overall survival, underlining a critical need of new therapeutic options. Unfortunately, although several molecular targets have been investigated, only very few recently approved agents, such as trastuzumab in the HER2-positive setting and ramucirumab, led to a clinical improvement in the outcome of metastatic gastric cancer patients. VEGF (vascular endothelial growth factor) is one of the most potent angiogenic factors and is a signalling molecule secreted by many solid tumours. Since high VEGF expression is one of the characteristic features of gastric carcinomas, targeting VEGF is therefore considered as a promising therapeutic strategy for gastric cancer. In the scenario of possible new target therapies with particular regard to angiogenesis, apatinib is a novel receptor tyrosine kinase inhibitor selectively targeting VEGFR-2. It is an orally-bioavailable agent currently being studied in several solid tumour types showing a promising activity in gastric cancer. Due to the recent positive results as a third line of treatment for metastatic gastric cancer patients, apatinib may be an interesting and novel type of targeted treatment for metastatic gastric cancer in several lines of therapy. In this review, we summarize the available data of apatinib, mainly focused on the clinical aspect, in advanced/metastatic gastric cancer.

Novel anti-angiogenic therapeutic strategies in colorectal cancer

INTRODUCTION

Anti-angiogenetic agents are currently the standard of care in metastatic CRC patients. Bevacizumab, aflibercept, regorafenib and recently ramucirumab have significantly improved both progression-free and overall survival in different lines of treatment. Since bevacizumab's approval, a number of novel anti-VEGF agents have been tested in preclinical and clinical models.

AREAS COVERED

This review is focused on the most recent clinical results of novel agents targeting VEGF and its receptors with a major focus on those investigated recently in clinical trials.

EXPERT OPINION

In the last 15 years, a number of new anti-angiogenetic agents have been tested. Unfortunately, most of them have demonstrated unacceptable toxicities or failed to show activity. When tested as single agents, encouraging preliminary results were reported with fruquintinib, famitinib, and nintedanib. Interesting novel mechanisms of action are also being explored: VGX-100 is a monoclonal antibody (mAb) which binds to VEGF-C, inhibiting activation of VEGFR-2 and VEGFR-3 when combined with bevacizumab; tanibirumab is a mAb which binds to VEGFR-2 and vanucizumab is a bispecific mAb binding both to VEGF-A and Angiopoietin-2. Data about the combination of these agents with chemotherapy are very encouraging, even though preliminary. However, the definition of specific predictive biomarkers remains a priority.

Metastatic gastric cancer treatment: Second line and beyond

Advanced gastric cancer (aGC), not amenable to curative surgery, is still a burdensome illness tormenting afflicted patients and their healthcare providers. Whereas combination chemotherapy has been shown to improve survival and tumor related symptoms in the frontline setting, second-line therapy (SLT) is subject to much debate in the scientific community, mainly because of the debilitating effects of GC, which would impede the administration of cytotoxic therapy. Recent data has provided sufficient evidence for the safe use of SLT in patients with an adequate performance status. Taxanes, Irinotecan and even some Fluoropyrimidine analogs were found to provide a survival advantage in this subset of patients. Most importantly, quality of life measures were also improved through the use of adequate therapy. Even more pertinent were the findings involving antiangiogenic agents, which would add measurable improvements without significantly jeopardizing the patients’ well-being. Further lines of therapy are cause for much more debate nowadays, but specific targeted agents have shown considerable promise in this context. We herein review noteworthy published data involving the use of additional lines of the therapy after failure of standard frontline therapies in patients with aGC.

Bevacizumab combined with docetaxel, oxaliplatin, and capecitabine, followed by maintenance with capecitabine and bevacizumab, as first-line treatment of patients with advanced HER2-negative gastric cancer: A multicenter phase 2 study

BACKGROUND

The current study was a multicenter, single-arm, phase 2 study performed to investigate the feasibility and efficacy of bevacizumab combined with docetaxel, oxaliplatin, and capecitabine (B-DOC) in patients with advanced human epidermal growth factor receptor 2 (HER2)-negative, previously untreated, gastric or gastroesophageal adenocarcinoma.

METHODS

Tumor HER2 status was determined centrally. Patients received 6 cycles of bevacizumab at a dose of 7.5 mg/kg, docetaxel at a dose of 50 mg/m(2) , and oxaliplatin at a dose of 100 mg/m(2) (all on day 1) combined with capecitabine at a dose of 850 mg/m(2) twice daily (days 1-14) every 3 weeks followed by maintenance with capecitabine and bevacizumab in patients with disease control. The primary objective was to demonstrate a progression-free survival (PFS) of >6.5 months, according to the 95% confidence interval (95% CI). Secondary endpoints included safety, objective response rate, overall survival (OS), analyses of circulating tumor cells (CTCs), and pharmacogenetic analyses.

RESULTS

Sixty eligible patients were enrolled. The median PFS was 8.3 months (95% CI, 7.2-10.9 months). The objective response rate was 70% (95% CI, 55%-83%) and the disease control rate was 96% (95% CI, 85%-99%). The median OS was 12.0 months (95% CI, 10.2-16.1 months). According to CTC-AE v4.0, the most common treatment-related grade ≥3 adverse events were neutropenia (20%), leukocytopenia (18%), diarrhea (15%), and nausea/vomiting (15%). The presence of CTCs at baseline was strongly predictive of PFS (hazard ratio [HR], 3.8; P =.007) and OS (HR, 3.4; P =.014). The methylenetetrahydrofolate reductase (MTHFR) 677C>T genotype was strongly associated with PFS (HR, 4.7 for TT vs CC or CT; P =.0007) and OS (HR, 5.9; P =.0001).

CONCLUSIONS

The B-DOC regimen plus maintenance was feasible and active. CTCs were found to be prognostic in patients treated with B-DOC. Docetaxel-based triplet chemotherapy as a backbone for targeted therapies is feasible and deserves further study. Cancer 2016;122:1434-1443. © 2016 American Cancer Society.

Targeted therapy for gastric cancer: Current status and future directions (Review)

According to the 2012 statistics of the International Agency for Research on Cancer (IARC), gastric cancer is the fifth most common malignancy, and the third leading cause of cancer-related deaths worldwide. Conventional chemotherapy and radiation have shown limited efficacy for advanced gastric cancer, showing an overall survival (OS) rate of ~10 months. Trastuzumab, a monoclonal antibody against human epidermal growth factor receptor 2 (HER2), is the first approved molecularly targeted agent for HER2-overexpressing gastric cancer, which was found to prolong the OS and the progression-free survival (PFS) of patients. However, HER2 overexpression is present only in a minority of patients with gastric cancer. Hence, other targeted agents are urgently needed. Ramucirumab, a novel human IgG1 monoclonal antibody that selectively targets the extracellular domain of VEGF receptor 2 (VEGFR2), is regarded as a new standard second-line treatment for patients with advanced gastric cancer. The combination of two or more targeted agents directed against two different molecular targets may improve the survival of patients with advanced gastric cancer. Although great efforts have been made, the effect of targeted therapy for gastric cancer is limited. One key reason is that participants in clinical trials for new targeted agents were not selected by detection of the targeted molecule. Here, we review clinical trials related to molecular targets such as anti-epidermal growth factor receptor signaling including anti-HER2 and anti-EGFR1, anti-VEGF signaling, anti-mammalian target of rapamycin (mTOR), tyrosine kinase inhibitors (TKIs) and anti-MET.

Novel targets in the treatment of advanced gastric cancer: a perspective review

Gastric cancer is responsible for a high burden of disease globally. Although more extensive use of chemotherapy together with the recent introduction of the two targeted agents trastuzumab and ramucirumab have contributed to marginal outcome prolongation, overall survival for patients with advanced stage disease remains poor. Over the last decade, a number of novel agents have been examined in clinical trials with largely disappointing results. Potential explanations for this are the absence of molecularly selected trial populations or weak predictive biomarkers within the context of a highly heterogeneous disease. In the recently published gastric cancer The Cancer Genome Atlas (TCGA) project a new classification of four different tumour subtypes according to different molecular characteristics has been proposed. With some overlap, several relatively distinct and potentially targetable pathways have been identified for each subtype. In this perspective review we match recent trial results with the subtypes described in the gastric cancer TCGA aiming to highlight data regarding novel agents under evaluation and to discuss whether this publication might provide a framework for future drug development.

Clinical efficacy of Apatinib in treatment of advanced gastric cancer

AIM: To evaluate the efficacy and safety of Apatinib in advanced gastric cancer patients after failure of second-line or beyond treatment.

METHODS: From October 2014 to August 2015, 60 patients with pathologically confirmed advanced gastric cancer who failed second line or beyond treatment were enrolled in the study. All the patients were given Apatinib 850 mg/d orally until disease progression. Clinical efficacy and adverse reactions were observed. Kaplan-Meier method was used for survival analysis.

RESULTS: According to the Response Evaluation Criteria in Solid Tumors (RECIST) standard, all the patients can be evaluated for therapeutic effects. Complete response (CR) rate was 0% (0/60), partial response (PR) rate was 3.33% (2/60), stable disease (SD) rate 38.33 (23/60), and progressive disease (PD) rate 58.33% (35/60). The objective response rate (CR + PR) and the disease control rate (CR + PR + SD) were 3.33% and 38.33% (23/60), respectively. The median progression-free survival time was 3.76 mo. Patients with α-fetoprotein (AFP) positive gastric cancer had the higher disease control rate and better survival compared to the AFP negative patients. Main adverse reactions were hypertension and bone marrow suppression.

CONCLUSION: Administration of Apatinib in advanced gastric cancer patients after failure of second-line or beyond treatment is still beneficial in terms of higher disease control rate and better survival, and adverse reactions are tolerable.

Randomized, Double-Blind, Placebo-Controlled Phase III Trial of Apatinib in Patients With Chemotherapy-Refractory Advanced or Metastatic Adenocarcinoma of the Stomach or Gastroesophageal Junction

PURPOSE

There is currently no standard treatment strategy for patients with advanced metastatic gastric cancer experiencing progression after two or more lines of chemotherapy. We assessed the efficacy and safety of apatinib, a novel vascular endothelial growth factor receptor 2 tyrosine kinase inhibitor, in patients with advanced gastric or gastroesophageal junction adenocarcinoma for whom at least two lines of prior chemotherapy had failed.

PATIENTS AND METHODS

This was a randomized, double-blind, placebo-controlled phase III trial. Patients from 32 centers in China with advanced gastric or gastroesophageal junction adenocarcinoma, for whom two or more prior lines of chemotherapy had failed, were enrolled. Patients were randomly assigned to oral apatinib 850 mg or placebo once daily. The primary end points were overall (OS) and progression-free survival (PFS).

RESULTS

Between January 2011 and November 2012, 267 patients were enrolled. Median OS was significantly improved in the apatinib group compared with the placebo group (6.5 months; 95% CI, 4.8 to 7.6 v 4.7 months; 95% CI, 3.6 to 5.4; P = .0149; hazard ratio, 0.709; 95% CI, 0.537 to 0.937; P = .0156). Similarly, apatinib significantly prolonged median PFS compared with placebo (2.6 months; 95% CI, 2.0 to 2.9 v 1.8 months; 95% CI, 1.4 to 1.9; P < .001; hazard ratio, 0.444; 95% CI, 0.331 to 0.595; P < .001). The most common grade 3 to 4 nonhematologic adverse events were hand-foot syndrome, proteinuria, and hypertension.

CONCLUSION

These data show that apatinib treatment significantly improved OS and PFS with an acceptable safety profile in patients with advanced gastric cancer refractory to two or more lines of prior chemotherapy.

Targeted therapies in gastric cancer treatment: where we are and where we are going

Gastric cancer (GC) is one of the most common malignancies and a major cause of cancer-related deaths worldwide. Its incidence has significantly declined over the last few decades, probably due to the identification of specific etiologic agents such as Helicobacter pylori and other dietary and environmental risk factors. Nevertheless, most of the cases are unfortunately diagnosed at an advanced stage justifying median overall survival rates frequently not exceeding one year. Palliative combination chemotherapy usually represented by a platinum-based doublet is the mainstay of treatment in the metastatic setting. Adding a third drug such as an anthracycline or a taxane has been shown to improve response rate and provide limited survival benefits in fit selected patients. Unlike other tumors, the introduction of molecularly targeted drugs in the medical armamentarium for GC is relatively recent with trastuzumab and ultimately ramucirumab constituting the only agents approved to date. Recent advances in the understanding of GC biology have led to the development of novel targeted therapies holding the promise to further improve treatment outcomes. The aim of this paper is to review the main available data coming from clinical trials of targeted drugs and to describe some of the most interesting molecules in clinical development in GC. These include drugs targeting EGFR, angiogenesis, c-MET, FGFR2, mTOR and immune checkpoints.

Intracellular autocrine VEGF signaling promotes EBDC cell proliferation, which can be inhibited by Apatinib

Tumor cells produce vascular endothelial growth factor (VEGF) which can interact with membrane or cytoplasmic VEGF receptors (VEGFRs) to promote cell growth. We aimed to investigate the role of extracellular/intracellular autocrine VEGF signaling and Apatinib, a highly selective VEGFR2 inhibitor, in extrahepatic bile duct cancer (EBDC). We found conditioned medium or recombinant human VEGF treatment promoted EBDC cell proliferation through a phospholipase C-γ1-dependent pathway. This pro-proliferative effect was diminished by VEGF, VEGFR1 or VEGFR2 neutralizing antibodies, but more significantly suppressed by intracellular VEGFR inhibitor. The rhVEGF induced intracellular VEGF signaling by promoting nuclear accumulation of pVEGFR1/2 and enhancing VEGF promoter activity, mRNA and protein expression. Internal VEGFR2 inhibitor Apatinib significantly inhibited intracellular VEGF signaling, suppressed cell proliferation in vitro and delayed xenograft tumor growth in vivo, while anti-VEGF antibody Bevacizumab showed no effect. Clinically, overexpression of pVEGFR1 and pVEGFR2 was significantly correlated with poorer overall survival (P = .007 and P = .020, respectively). In conclusion, the intracellular autocrine VEGF loop plays a predominant role in VEGF-induced cell proliferation. Apatinib is an effective intracellular VEGF pathway blocker that presents a great therapeutic potential in EBDC.

Targeted therapies in gastric cancer and future perspectives

Advanced gastric cancer (AGC) is associated with a high mortality rate and, despite multiple new chemotherapy options, the survival rates of patients with AGC remains poor. After the discovery of targeted therapies, research has focused on the new treatment options for AGC. In the last two decades, many targeted molecules were developed against AGC. Currently, two targeted therapy molecules have been approved for patients with AGC. In 2010, trastuzumab was the first molecule shown to improve survival in patients with HER2-positive AGC as part of a first-line combination regimen. In 2014, ramucirumab was the second targeted molecule to improve survival rates and was suggested as treatment for patients with AGC who had progressed after first-line platinum plus fluoropyrimidine with or without anthracycline chemotherapy. Ramucirumab was the first targeted therapy acting as a single agent in patients with advanced gastroesophageal cancers. Although these two molecules were introduced into clinical use, many other promising molecules have been tested in phase I-II trials. It is obvious that in the near future many different targeted therapies will be in use for treatment of AGC. In this review, the current status of targeted therapies in the treatment of AGC and gastroesophageal junction tumors, including HER (2-3) inhibitors, epidermal growth factor receptor inhibitors, tyrosine kinase inhibitors, antiangiogenic agents, c-MET inhibitors, mammalian target of rapamycin inhibitors, agents against other molecular pathways fibroblast growth factor, Claudins, insulin-like growth factor, heat shock proteins, and immunotherapy, will be discussed.

Current Molecular Targeted Therapy in Advanced Gastric Cancer: A Comprehensive Review of Therapeutic Mechanism, Clinical Trials, and Practical Application

Despite the great progress in the treatment of gastric cancer, it is still the third leading cause of cancer death worldwide. Patients often miss the opportunity for a surgical cure, because the cancer has already developed into advanced cancer when identified. Compared to best supportive care, chemotherapy can improve quality of life and prolong survival time, but the overall survival is often short. Due to the molecular study of gastric cancer, new molecular targeted drugs have entered the clinical use. Trastuzumab, an antibody targeting human epidermal growth factor receptor 2 (HER2), can significantly improve survival in advanced gastric cancer patients with HER2 overexpression. Second-line treatment of advanced gastric cancer with ramucirumab, an antibody targeting VEGFR-2, alone or in combination with paclitaxel, has been proved to provide a beneficial effect. The VEGFR-2 tyrosine kinase inhibitor, apatinib, can improve the survival of advanced gastric cancer patients after second-line chemotherapy failure. Unfortunately, none of the EGFR targeting antibodies (cetuximab or panitumumab), VEGF targeting monoclonal antibodies (bevacizumab), mTOR inhibitor (everolimus), or HGF/MET pathway targeting drugs has a significant survival benefit. Many other clinical trials based on molecular markers are underway. This review will summarize targeted therapies for advanced gastric cancer.

Recurrence of gastric cancer in patients who are disease-free for more than 5 years after primary resection

BACKGROUND

Late recurrence of gastric cancer is rare and there are few data on recurrence in patients who are disease free for >5 years after gastrectomy. The aim of this study was to evaluate the predictors and status of tumor recurrence among these patients.

METHODS

Clinicopathologic characteristics, patterns of recurrence, and postrecurrence survival were analyzed in patients who were diagnosed as disease free at 5 years postoperatively and thereafter experienced recurrence. Independent factors associated with the late recurrence were analyzed.

RESULTS

Among 1,573 patients who underwent curative surgery from June 1992 to December 2006, 348 patients had recurrence. Of them, 7.6% (n = 25) suffered from late recurrence after 5 years after gastrectomy. Among patients who were diagnosed as disease free at 5 years after surgery, it accounted for 2.8% (25/902). Cases with late recurrence were characterized by more aggressive clinicopathologic features than those without recurrence. The median time to recurrence was 88.8 months (range, 64.8-238.0); of the 25 patients, 18 (72.0%) had recurrence within 8 years after surgery. The most common pattern was peritoneal recurrence (n = 19; 76.0%). The estimated median survival after recurrence was 9.4 months. On multivariate analysis, pT4 classification was the only independent risk factor for late recurrence. There were 185 patients with pT4 tumor who had no recurrence at 5 years after surgery; 19 (10.3%) had late recurrence.

CONCLUSION

pT4 tumor was the only important predictor of late recurrence. Whether extended follow-up for T4 tumors affects survival needs to be demonstrated in more large-scale studies.

Controlling angiogenesis in gastric cancer: A systematic review of anti-angiogenic trials

PURPOSE

Angiogenesis is a promising therapeutic target to inhibit tumor growth. This review summarizes data from clinical trials of anti-angiogenic agents in gastric cancer.

DESIGN

A systematic search of PubMed, Embase and conference databases is performed to identify clinical trials with specific anti-angiogenic agents in gastric cancer treatment

RESULTS

The risk of disease progression (37-52%) and death (19-22%) with ramucirumab as second-line treatment decreases in phase III trials in advanced gastric cancer. No significant improvement in overall survival (OS) with the addition of bevacizumab to chemotherapy is shown. Bevacizumab or ramucirumab combined with traditional chemotherapy is associated with higher adverse event rate compared to chemotherapy alone. Except for apatinib, phase II trials of other tyrosine kinase inhibitors (TKIs) may improve overall response rate, but there are no significant improvements in OS and progression-free survival (PFS) when combined with chemotherapy.

CONCLUSION

Phase III trials in advanced gastric cancer have demonstrated improved outcome with ramucirumab as second-line treatment. Most of the other studies on anti-angiogenic agents in gastric cancer have reported improvement in response rate but not in OS compared to chemotherapy alone. Future research is expected in optimizing the anti-angiogenic therapy combined with traditional treatment.

Targeted therapy for advanced gastric cancer: A review of current status and future prospects

In the West in particular, the vast majority of gastric cancer (GC) patients present with advanced-stage disease. Although combination chemotherapy is still the most important component of treatment for these patients, it confers a modest survival advantage. Recently, increased knowledge of the key molecular signaling pathways involved in gastric carcinogenesis has led to the discovery of specific molecular-targeted therapeutic agents. Some of these agents such as trastuzumab and ramucirumab have changed the treatment paradigm for this disease. In this paper, we will summarize the current clinical status of targeted drug therapy in the management of GC.

Targeting HER 2 and angiogenesis in gastric cancer

Gastric cancer is one of the most commonly diagnosed and the second leading cause of cancer death worldwide. Surgery combined with multimodal therapy remains the only curative therapy. However, local relapse or distant metastases occur in more than 50% of radically resected patients. Due to molecular therapies, targeting HER2 and angiogenesis, major advances in the treatment of gastric cancer could be achieved. Nevertheless, development of resistance to monoclonal antibodies, such as trastuzumab, is arising. Currently a number of promising new therapeutic are under investigation, combining chemotherapy with newly developed agents to overcome cancer resistance. In this review we report current clinical applications of targeted therapies and overview ongoing trials, investigating the use of monoclonal antibodies in (HER2 positive) gastric cancer.

Systemic therapy beyond first-line in advanced gastric cancer: An overview of the main randomized clinical trials

Following progression on first-line platinum and fluoropyrimidine-based chemotherapy, prognosis for advanced gastric cancer patients is extremely poor. Thus, new and effective treatments are required. Based on positive results of recent randomized controlled trials, second-line monochemotherapies with either irinotecan or taxanes confer a median overall survival of approximately 5 months in gastro-esophageal and gastric adenocarcinoma. Combination of weekly paclitaxel and ramucirumab, a novel anti-angiogenic VEGFR2 antibody, pushes the overall survival up to over 9.5 months, whereas apatinib, a novel oral VEGFR2 tyrosine kinase inhibitor, seems to be promising in heavily pretreated patients. In contrast, the role of EGFR/HER2 and mTOR inhibitors is controversial. Studies are heterogeneous for tumor population, geographical areas, quality of life assessment, type of first-line therapy and response to that, making clinical practice application of the trial results difficult. Furthermore, sustainability is challenging due to high cost of novel biotherapies.

Vascular and Metabolic Implications of Novel Targeted Cancer Therapies: Focus on Kinase Inhibitors

Novel targeted cancer therapies, especially kinase inhibitors, have revolutionized the treatment of many cancers and have dramatically improved the survival of several types of malignancies. Because kinases not only are important in cancer development and progression, but also play a critical role in the cardiovascular (CV) system and metabolic homeostasis, important CV and metabolic sequelae have been associated with several types of kinase inhibitors. This paper reviews the incidences and highlights potential mechanisms of vascular and metabolic perturbations associated with 3 classes of commonly used kinase inhibitors that target the vascular endothelial growth factor signaling pathway, the ABL kinase, and the phosphoinositide 3-kinase/AKT/mammalian target of rapamycin signaling pathway. We propose preventive, screening, monitoring, and management strategies for CV care of patients treated with these novel agents.

Novel targeted agents for the treatment of lung cancer in China

Since the discovery of epidermal growth factor receptor mutations and epidermal growth factor receptor tyrosine kinase inhibitors, lung cancer treatment in China has entered the precision era. However, novel targeted agents based on novel biomarkers still need to be developed. In the current study, the authors review the biomarker features of lung cancer in the Chinese population and the novel agents that are aimed at novel targets. Furthermore, they discuss issues that require improvement for the production of novel drugs and provided future directions for development in China.

Apatinib for molecular targeted therapy in tumor

As tumor angiogenesis is one of the hallmarks of cancer, the inhibition of vascular endothelial growth factor signaling has become an attractive anticancer approach. Apatinib, a small-molecule inhibitor of vascular endothelial growth factor receptor-2, has demonstrated encouraging anticancer activity across a broad range of malignancies, including gastric cancer, non-small-cell lung cancer, breast cancer, and hepatocellular carcinoma. In this up-to-date review, focus is not only on the structure, mechanisms, and pharmacokinetics of apatinib, but also on summarizing clinical trials and making recommendations of apatinib for patients with advanced solid tumors.

Meta-analysis of regression of advanced solid tumors in patients receiving placebo or no anti-cancer therapy in prospective trials

BACKGROUND

A meta-analysis of prospective trials systematically investigated regression of advanced solid tumors in patients receiving placebo or no anticancer therapy to inform on spontaneous regressions.

PATIENT AND METHODS

Arms of randomized controlled trials (RCTs) of metastatic solid tumors receiving placebo or no anti-cancer therapy were used. Statistical analyses were conducted to calculate the overall response rate (ORR) and to detect differentials based on histology, progression at baseline and prior therapies.

RESULTS

A total of 7676 patients were evaluable from 61 RCTs evaluating 18 solid tumors. The ORR was 1.95% (95% CI: 1.52-2.48%). There was no significant effect of histology (p=0.110), baseline progressive disease (p>0.20) or the line of therapy (p>0.20) on ORR.

CONCLUSIONS

Spontaneous regressions are seen across all advanced solid tumors. Some malignancies demonstrated higher rates of spontaneous regressions and may be relatively immunotherapy responsive.

Targeted therapy in gastroesophageal cancers: past, present and future

Gastroesophageal cancer is a significant global problem that frequently presents at an incurable stage and has very poor survival with standard chemotherapy approaches. This review will examine the epidemiology and molecular biology of gastroesophageal cancer and will focus on the key deregulated signaling pathways that have been targeted in the clinic. A comprehensive overview of clinical data highlighting successes and failures with targeted agents will be presented. Most notably, HER2-targeted therapy with the monoclonal antibody trastuzumab has proven beneficial in first-line therapy and has been incorporated into standard practice. Targeting the VEGF pathway has also proven beneficial, and the VEGFR-targeted monoclonal antibody ramucirumab is now approved for second-line therapy. In contrast to these positive results, agents targeting the EGFR and MET pathways have been evaluated extensively in gastroesophageal cancer but have repeatedly failed to show benefit. An increased understanding of the molecular predictors of response to targeted therapies is sorely needed. In the future, improved molecular pathology approaches should subdivide this heterogeneous disease entity to allow individualization of cancer therapy based on integrated and global identification of deregulated signaling pathways. Better patient selection, rational combinations of targeted therapies and incorporation of emerging immunotherapeutic approaches should further improve the treatment of this deadly disease.

Comprehensive analyses using next-generation sequencing and immunohistochemistry enable precise treatment in advanced gastric cancer

BACKGROUND

In advanced gastric cancer (AGC), most clinical trials are designed on the basis of protein expression or gene amplification of specific genes. Recently, next-generation sequencing (NGS) allowed us to comprehensively profile the tumor gene status. This study aimed to elucidate the profiling between gene alterations and protein expression in AGC to aid in future clinical trials on AGC.

PATIENTS AND METHODS

Formalin-fixed, paraffin-embedded tumor samples from 121 stage III/IV gastric cancer patients were examined for protein expression of tyrosine kinase receptors (RTKs; ERBB2, EGFR, c-MET, and FGFR2) using immunohistochemistry (IHC). Furthermore, 409 cancer-related genes were sequenced to detect mutations and copy number variations using NGS.

RESULTS

Most ERBB2 overexpression (IHC 3+) cases (80.0%) had ERBB2 amplification and did not have other RTK amplification or oncogene mutations. However, one-fourth of MET overexpression cases (25.0%) had ERBB2 alterations. EGFR and FGFR2 overexpression cases had ERBB2 alterations or other gene alterations such as KRAS or PIK3CA. On the other hand, most of the four RTK amplification cases (88.2%) were mutually exclusive with each amplification. However, RTK amplification did not simply correlate with protein overexpression, whereas cases with RTK high-level amplification had protein overexpression and rarely showed other co-existing gene alterations.

CONCLUSION

AGC involves a complicated arrangement of protein expression and gene alterations. Comprehensive analyses of NGS and IHC will be necessary to design the optimal therapy for treating the appropriate population of patients in future clinical trials.

Clinical utility of ramucirumab in advanced gastric cancer

Gastric cancer is currently the third most common cause of cancer deaths worldwide. Prognosis remains poor with most patients presenting with advanced or metastatic disease. A better understanding of angiogenesis has led to the investigation of drugs that inhibit the vascular endothelial growth factor (VEGF) pathway including anti-VEGF antibody therapy (eg, bevacizumab), inhibitors of angiogenic receptor tyrosine kinases (eg, sunitinib, sorafenib, apatinib, regorafenib), and inhibitors of vascular endothelial growth factor receptors (VEGFRs) (eg, ramucirumab). Ramucirumab, a VEGFR-2 inhibitor, is the first anti-angiogenic agent approved by the US Food and Drug Administration for use in the treatment of advanced gastric cancers. This review will focus on the clinical utility and potential use of ramucirumab in advanced gastric cancer.

The combinational therapy of trastuzumab and cetuximab inhibits tumor growth in a patient-derived tumor xenograft model of gastric cancer

PURPOSE

Gastric cancer (GC) is one of the leading causes of cancer mortality worldwide. Although therapeutic strategies for GC have improved, the prognosis for advanced GC remains poor. Herein, the present study sought to design a personalized cancer therapy specific to a stage III GC patient.

METHODS

The tumor was surgically removed and was used to establish a patient-derived tumor xenograft (PDTX) model utilizing nude mice. Various molecular-targeted anticancer treatments were tested in the study, including control (no treatment), bevacizumab, cetuximab, bevacizumab + cetuximab, trastuzumab, and trastuzumab + cetuximab.

RESULTS

Trastuzumab + cetuximab treatment exhibited the best antitumor growth effect, followed by trastuzumab, bevacizumab + cetuximab, cetuximab, and bevacizumab. Similarly, trastuzumab + cetuximab was also the most effective treatment at inducing apoptosis and cell cycle arrest in primary cultures of the patient's gastric cancer cells. Among all treatments tested in the study, trastuzumab + cetuximab showed the most profound effect in reducing the protein expression of proliferation and metastatic markers (VEGF, MMP-7, EGFT, Ki-67 and, PCNA) in tumors obtained from PDTX models, which may be the mechanism underlying the profound antitumor growth effect exerted by trastuzumab + cetuximab.

CONCLUSIONS

The data indicate that trastuzumab + cetuximab combinational therapy should be the most effective antitumor growth therapy for the GC patient whom we took the cancer cells from.

A Case Report of Gastrointestinal Hemorrhage and Perforation During Apatinib Treatment of Gastric Cancer

Apatinib is a novel tyrosine kinase inhibitor targeting vascular endothelial growth factor receptor-2, which shows good efficacy and safety in clinical trials for chemotherapy-refractory gastric cancer patients. Till now, there is no case report after apatinib came in the market. We presented a 55-year-old Chinese woman with advanced gastric cancer, who received apatinib after failure of second-line chemotherapy. On the 19th day of apatinib administration, she suffered from gastrointestinal hemorrhage. Then, her condition rapidly deteriorated to gastrointestinal perforation. Although the patient received timely medical and surgical treatment, she finally died of septic shock. Although apatinib shows exciting efficacy and good tolerance in phase II and III clinical trials, this novel targeted drug should be prescribed carefully and close clinical monitoring is needed when using it.

Chemotherapy beyond second-line in advanced gastric cancer

Patients with advanced gastric cancer (AGC) can be treated with multiple lines of chemotherapy. Although several randomized trials have demonstrated the benefit of second-line chemotherapy compared with best supportive care, there is no evidence that further lines of chemotherapy will result in substantial prolongation of survival. Despite this, the practice of offering chemotherapy beyond second-line agents to AGC patients is not uncommon if their performance status is well-preserved and they are willing to receive subsequent active treatments. The choice of chemotherapeutic agents depends on the patient's prior regimens. However, there are important controversial issues in the salvage setting of AGC, including a subset of patients who may benefit from chemotherapy, that still remain unanswered. This report reviews the available evidence regarding the impact of third- and subsequent lines of chemotherapy on survival and quality of life in patients with AGC.

Angiogenic inhibitors in gastric cancers and gastroesophageal junction carcinomas: A critical insight

Advanced gastric cancer ranks second as the global leading cause of cancer-related death and improvements in systemic chemotherapy have reached a plateau. Advanced molecular sequencing techniques help identifying patients more likely to respond to targeted agents; nevertheless we are still far from major breakthroughs. Although antiangiogenic drugs have produced notable advances, redundant pathways or mechanisms of resistance may limit their efficacy. Novel compounds have been recently developed to specifically target VEGF receptors, PlGF, FGF, MET, and angiopoietin. Ramucirumab, a monoclonal antibody specifically directed against the VEGFR-2, has emerged as a novel therapeutic opportunity. REGARD and RAINBOW were the first phase III studies to report the value of this strategy in gastric cancer patients, and other ongoing trials are testing novel antiangiogenic compounds. The aim of our review is to present the state-of-the-art of novel antiangiogenic compounds in advanced gastric cancer, underlying the biology, their mechanism of action, and their clinical results.

Critical evaluation of ramucirumab in the treatment of advanced gastric and gastroesophageal cancers

Gastric (GC) and gastroesophageal junction (GEJ) cancers are two global health problems with a relatively high mortality, particularly in the advanced stage. Inhibition of angiogenesis is now contemplated as a classic treatment preference for myriad tumor types encompassing renal cell carcinoma, non-small cell lung cancer, colorectal cancer, glioblastoma, and ovarian cancer, among others. Bevacizumab and ramucirumab have been widely investigated in GC and GEJ cancer, with some controversy about their therapeutic role. Ramucirumab is a monoclonal antibody for vascular endothelial growth factor receptor-2, with demonstrated activity both as a monotherapy and as a part of combination strategy in the management of advanced GC/GEJ cancer. In this review article, we present a critical evaluation of the preclinical and clinical data underlying the use of this drug in this indication. Moreover, we provide a spotlight on the future perspectives in systemic therapy for advanced GC/GEJ cancer.

Determination and Pharmacokinetic Study of Apatinib in Rat Plasma by UPLC

In this study, a simple, sensitive, and robust analytical method based on ultra-performance liquid chromatography (UPLC) has been developed for the determination of apatinib in rat plasma using carbamazepine as internal standard (IS). After sample preparation by a simple liquid-liquid extraction, chromatography was performed on an Acquity UPLC BEH C18 column (2.1 × 50 mm, 1.7 µm particle size) and total run time was 2.0 min. The method was linear over the concentration range 5-1000 ng/mL with a lower limit of quantification of 5 ng/mL. Inter- and intraday precision were all within 6.5% and the accuracy was ≤3.5%. Recoveries of apatinib and IS were >80%. Stability studies showed that apatinib was stable under a variety of storage conditions. The method was successfully applied to a pharmacokinetic study involving oral administration of apatinib to rats.

Multimodal treatment of gastric cancer in the west: Where are we going?

The incidence of gastric cancer (GC) is decreasing worldwide, especially for intestinal histotype of the distal third of the stomach. On the contrary, proximal location and diffuse Lauren histotype have been reported to be generally stable over time. In the west, no clear improvement in long-term results was observed in clinical and population-based studies. Results of treatment in these neoplasms are strictly dependent on tumor stage. Adequate surgery and extended lymphadenectomy are associated with good long-term outcome in early-stage cancer; however, results are still unsatisfactory for advanced stages (III and IV), for which additional treatments could provide a survival benefit. This implies a tailored approach to GC. The aim of this review was to summarize the main multimodal treatment options in advanced resectable GC. Perioperative or postoperative treatments, including chemotherapy, chemoradiotherapy, targeted therapies, and hyperthermic intraperitoneal chemotherapy have been reviewed, and the main ongoing and completed trials have been analyzed. An original tailored multimodal approach to non-cardia GC has been also proposed.

Systemic chemotherapy as a main strategy for liver metastases from gastric cancer

BACKGROUND

Liver metastasis is associated with poor prognosis in gastric cancer. Surgical resection and systemic chemotherapy have been reported to be effective in gastric cancer with liver metastasis (GCLM). However, the best strategy for GCLM has not been established.

METHODS

From May 2009 to July 2014, a consecutive series of GCLM patients in Zhongshan Hospital of Fudan University were studied. Treatment strategies were evaluated with regard to different extents of metastases.

RESULTS

A total of 163 patients were included. The overall survival was 10.1 months. Active treatment significantly prolongs the survival of GCLM patients. The overall survival time for patients with liver-limited metastases and extra-hepatic liver metastases was 11.6 mo and 8.7 mo, respectively (P = 0.012). The median survival time for liver-limited disease of H1, H2 and H3 was 14.2, 15.8, and 8.5 months, respectively (H3 vs H2, P = 0.001; H3 vs H1, P = 0.000; H1 vs H2, P = 0.900). Systemic chemotherapy was chosen as the main strategy for the 'extensive' patients with extra-hepatic metastases and H3 type liver-limited metastases. Patients' survival was benefited by multi-line chemotherapy. No differences were shown between systemic chemotherapy and curative resection or palliative resection in H1 and H2 liver-limited metastases (16.0 mo vs 12.0 mo, P = 0.711; 16.0 vs 18.8 months, P = 0.654).

CONCLUSION

Systemic chemotherapy was the main treatment for gastric cancer patients with liver metastases. Curative resection could be considered for highly selected patients.

A systematic review and meta-analysis of randomized trials on the role of targeted therapy in the management of advanced gastric cancer: Evidence does not translate?

It is still uncertain if targeted therapy-based regimens in advanced gastric cancer actually produce survival benefit. To shed light on this important question, we performed a systematic review and meta-analyses on each relevant targeted-pathway. By searching literature databases and proceedings of major cancer meetings in the time-frame 2005-2014, 22 randomized clinical trials exploring targeted therapy for a total of 7022 advanced gastric cancer patients were selected and included in the final analysis. Benefit was demonstrated for antiangiogenic agents in terms of overall survival (HR 0.759; 95%CI 0.655-0.880; p < 0.001). Conversely no benefit was found for EGFR pathway (HR 1.077; 95%CI 0.847-1.370; p = 0.543). Meta-analysis of HER-2 pathway confirmed improvement in terms of survival outcome, already known for this class of drugs (HR 0.823; 95%CI 0.722-0.939; p = 0.004). Pooled analysis demonstrated a significant survival benefit (OS: HR 0.823; PFS: HR 0.762) with acceptable tolerability profile for targeted-based therapies as compared to conventional treatments. This finding conflicts with the outcome of most individual studies, probably due to poor trial design or patients selection. In conclusion, our findings demonstrate a significant survival benefit for targeted therapy in its whole, which can be ascribed to anti-angiogenic and anti-HER2 agents.

Current and Future Therapies for Advanced Gastric Cancer

The treatment of patients with advanced gastric cancer remains a challenging area of oncology. Extensive trials of differing chemotherapy regimens have yielded no international consensus on the optimal combination, and overall survival with chemotherapy alone remains poor. Recently an improved understanding of the molecular drivers of the disease has opened up promising new avenues of treatment through the use of biological targeted agents. The anti-HER2 monoclonal antibody trastuzumab was the first targeted agent to significantly prolong survival in the first-line treatment of a molecularly-selected subgroup of patients. More recently the anti-vascular endothelial growth factor receptor 2 monoclonal antibody ramucirumab has demonstrated a modest survival benefit in previously treated patients as both a monotherapy and in combination with chemotherapy. Immunotherapy and the use of checkpoint inhibitors are a further exciting area of development with promising preliminary results for the activity of the anti-Programmed Death 1 Receptor antibody pembrolizumab and ongoing trials of a number of immune-modulating agents. Continuing research to identify novel targets and therapies aims to make further incremental gains in survival. In this review we outline the evidence base supporting current chemotherapy regimens and describe the latest advances in the development and use of molecularly targeted and immune-modulating agents.

Emerging kinase inhibitors of the treatment of gastric cancer

INTRODUCTION

Gastric cancer (GC) is the fifth most common malignancy in the world. In the last years, for the first time in literature, the addition of a targeted therapy to standard chemotherapy has proved to prolong median overall survival. In this scenario, kinase inhibitors (KIs), smaller intracellular agents, could be an interesting and novel type of targeted treatment of metastatic GC both in first and further lines of therapy.

AREAS COVERED

Several KI have been evaluated in the preclinical setting. This review will underline the most relevant targeted pathways involved in GC tumorigenesis and disease progression including EGFR, VEGFR, c-MET, mTOR, fibroblast growth factor receptor, Src and Aurora kinases.

EXPERT OPINION

Despite the good results of TOGA, RAINBOW and REGARD trials about the addition of monoclonal antibodies to standard of care in GC, the addition of KI seems not to achieve comparable interesting results in management of GC. However, an improved patient selection before and during treatment according to molecular characteristics, as well as combination studies evaluating the synergistic effect of combination schedules of different KIs and standard chemotherapy, or KI plus KI or KI plus antibodies-based therapy may reveal interesting results and lead to understand mechanisms of multi-drug resistance.

Targeted therapy in gastric cancer

Gastric cancer is often diagnosed at an advanced stage. Although chemotherapy prolongs survival and improves quality of life, the survival of gastric cancer patients with advanced disease is short. Thanks to recent insights into the molecular pathways involved in gastric carcinogenesis, new targeted treatment options have become available for gastric cancer patients. Trastuzumab, an antibody targeted to HER-2, was shown to improve survival of advanced gastric cancer patients harboring HER-2 overexpression due to gene amplification in their tumor cells, and is currently also explored in adjuvant and neoadjuvant settings. Another agent with promising results in clinical trials is ramucirumab, an antibody targeting VEGFR-2. No clear survival benefit, however, were experienced with agents targeting EGFR (cetuximab, panitumumab), VEGF-A (bevacizumab), or mTOR (everolimus). Drugs targeting c-MET/HGF are currently under investigation in biomarker-selected cohorts, with promising results in early clinical trials. This review will summarize the current status of targeted treatment options in gastric cancer.

Progression-free survival as a surrogate endpoint for overall survival in patients with third-line or later-line chemotherapy for advanced gastric cancer

BACKGROUND

The correlation between overall survival (OS) and progression-free survival (PFS) has been evaluated in patients with metastatic or advanced gastric cancer who have received first-line and/or second-line chemotherapy. However, no corresponding analysis has been done for patients who have undergone third-line or later-line chemotherapy.

METHODS

A total of 303 patients from the Phase II/III studies of apatinib were pooled (the Phase II study as a training data set, the Phase III study as a testing data set). Landmark analyses of PFS at 2 months from randomization were performed to minimize lead time bias. The Cox proportional hazard model was used to test for the significance effect of PFS rate at 2 months in predicting OS. Additionally, the PFS/OS correlations were evaluated by the normal induced copula (National Institute for Health and Care Excellence) estimation model.

RESULTS

The median OS was 3.37 months (95% confidence interval 2.63-3.80) in patients who experienced progression at 2 months and 5.67 months in patients who did not (95% confidence interval 4.83-6.67; P<0.0001). Compared with patients who did not progress at 2 months, the adjusted hazard ratio for death was 3.39 (95% confidence interval 1.79-6.41; P<0.0001) for patients who experienced progression at 2 months. Moreover, the correlation of PFS/OS was 0.84 (95% confidence interval 0.74-0.90). Similar results were found in the testing data set.

CONCLUSION

These results indicate that PFS correlates strongly with OS, suggesting PFS may be a useful early endpoint for patients with advanced gastric cancer who have undergone third-line or later-line chemotherapy. These observations require prospective validation.

Establishment and characterization of patient-derived tumor xenograft using gastroscopic biopsies in gastric cancer

The patient-derived tumor xenograft (PDTX) model has become the most realistic model for preclinical studies. PDTX models of gastric cancer using surgical tissues are reported occasionally; however, the PDTX models using gastroscopic biopsies, which are best for evaluating new drugs, are unreported. In our study, a total of 185 fresh gastroscopic biopsies of gastric cancer were subcutaneously transplanted into NOD/SCID (Nonobese Diabetic/Severe Combined Immunodeficiency) mice. Sixty-three PDTX models were successfully established (34.1%, 63/185) and passaged to maintain tumors in vivo, and the mean latency period of xenografts was 65.86 ± 32.84 days (11–160 days). Biopsies of prior chemotherapy had a higher transplantation rate (52.1%, 37/71) than biopsies after chemotherapy (21.9%, 25/114; P = 0.000). No differences were found between the latency period of xenografts and characteristics of patients. The pathological and molecular features of PDTX as well as chemosensitivity were highly consistent with those of primary tumors of patients. The genetic characteristics were stable during passaging of PDTX models. In summary PDTX models using gastroscopic biopsies in gastric cancer were demonstrated for the first time, and the biological characteristics of the PDTX models were highly consistent with patients, which provided the best preclinical study platform for gastric cancer.

Inhibition of β-catenin and STAT3 with a curcumin analog suppresses gastric carcinogenesis in vivo

BACKGROUND

Potent chemotherapy for advanced gastric cancer has not been completely established. Many molecularly targeted therapies are under investigation, but their therapeutic outcomes are not promising because they do not target specific and/or critical targets of gastric carcinogenesis. Although the molecular basis of gastric carcinogenesis remains poorly understood, nuclear localization of β-catenin was observed in approximately 50 % of gastric cancer specimens. Recent studies have suggested that activation of signal transducer and activator of transcription 3 (STAT3) contributes to gastric carcinogenesis in a mouse model. A newly synthesized curcumin analog has inhibitory potential against β-catenin and STAT3.

METHODS

Using a transgenic mouse model of gastric cancer in which β-catenin, cyclooxygenase 2, and microsomal prostaglandin E synthase 1 activation is induced, we examined a curcumin analog with the most enhanced potential for treating gastric cancer through oral administration. Inhibition of these targets was demonstrated using microarray and immunohistochemical analyses.

RESULTS

The curcumin analog GO-Y031 decreased the incidence of gastric carcinogenesis to 54.5 % of that of the control (50.0 % vs 91.7 %, p = 0.043), and tumor size was reduced to 51.6 % of that of the control (1.6 mm vs 3.1 mm, p = 0.03). β-Catenin and STAT3 levels were suppressed to 26.2 % (p = 0.00023) and 44.8 % (p = 0.025), respectively, of those of the control. Moreover, macrophage infiltration was suppressed with GO-Y031.

CONCLUSION

β-Catenin and STAT3 can be pharmacologically inhibited in vivo with a curcumin analog, which effectively inhibits β-catenin and STAT3.

Gastric Carcinogenesis and Underlying Molecular Mechanisms: Helicobacter pylori and Novel Targeted Therapy

The oxygen-derived free radicals that are released from activated neutrophils are one of the cytotoxic factors of Helicobacter pylori-induced gastric mucosal injury. Increased cytidine deaminase activity in H. pylori-infected gastric tissues promotes the accumulation of various mutations and might promote gastric carcinogenesis. Cytotoxin-associated gene A (CagA) is delivered into gastric epithelial cells via bacterial type IV secretion system, and it causes inflammation and activation of oncogenic pathways. H. pylori infection induces epigenetic transformations, such as aberrant promoter methylation in tumor-suppressor genes. Aberrant expression of microRNAs is also reportedly linked to gastric tumorogenesis. Moreover, recent advances in molecular targeting therapies provided a new interesting weapon to treat advanced gastric cancer through anti-human epidermal growth factor receptor 2 (HER-2) therapies. This updated review article highlights possible mechanisms of gastric carcinogenesis including H. pylori-associated factors.

Targeting vascular endothelial growth factor (VEGF) pathway in gastric cancer: preclinical and clinical aspects

The prognosis of advanced gastric cancer has been dreadful with the majority of patients dying of their disease within 1 year of the diagnosis. In the advanced stage several therapeutic options can be discussed, including molecular targeted agents, but biological predicting factors are lacking. A number of molecular targets have been studied over the last decade bringing to several phase II studies; however very few agents moved into phase III clinical trials. The VEGFR-2 inhibitor monoclonal antibody ramucirumab has been recently approved in advanced progressing gastric cancer. This article reviews the basic science as well as clinical data of VEGF signaling in advanced gastric cancer with special emphasis on the different VEGF targeting agents tested previously in this disease.

Clinical advances in the development of novel VEGFR2 inhibitors

Angiogenesis inhibitors have produced significant advances in the treatment of several tumors including colorectal, lung, ovarian and renal carcinomas. These agents, however, modestly impact on the overall cure rate, and their activity is often limited because of the early outbreak of redundant pathways or resistance mechanisms. Moreover, no clear predictive factor has been identified for treatment selection in the clinic. Preclinical evidence suggest that antibodies targeting the vascular endothelial growth factor (VEGF) axis may exert their activity throughout the inhibition of VEGF receptor 2 (VEGFR2) phosphorylation, a key factor in the cancer angiogenic process. Among other molecules, ramucirumab, an intravenously administered, fully humanized monoclonal antibody (mAb) targeting the extracellular domain of the receptor, and apatinib, a potent oral inhibitor of the intracellular domain, are emerging as original antiangiogenic opportunities. This up-to-date review focuses on the development of VEGFR2 inhibitors across multiple cancers and presents results of the most recent researches, ranging from early phase I studies to randomized phase III trials, in which those drugs have been tested as a single-agent or in combination with different chemotherapy regimens.

Apatinib for the treatment of gastric cancer

INTRODUCTION

Antiangiogenesis therapy plays an important role in cancer treatment. Apatinib mesylate, a small molecule tyrosine kinase inhibitor targeting vascular endothelial growth factor receptor-2, has been recommended as third-line treatment for metastatic gastric cancer patients.

AREAS COVERED

The current review summarizes the publications and conference reports relating to apatinib from preclinical and clinical research in gastric cancer. Apatinib showed good safety, tolerance and treatment efficacy in Phase I/II studies. In a Phase III study, apatinib prolonged the median overall survival of patients with chemotherapy-refractory metastatic gastric cancer by 55 days and the median progression-free survival by 25 days compared with placebo.

EXPERT OPINION

Apatinib is a new treatment option for advanced gastric cancer. Apatinib is expected to have a broader application when it has been evaluated worldwide. The key issues are to find biomarkers and overcome drug resistance.

Gastrointestinal cancer. Over the RAINBOW--renaissance in antiangiogenesis

The RAINBOW study has demonstrated that ramucirumab plus paclitaxel as second-line treatment for advanced-stage gastric cancer prolongs survival compared with paclitaxel alone. These data confirm that ramucirumab represents a new effective treatment option for gastric cancer. Nevertheless, new treatment options remain eagerly awaited in this disease with dismal outcomes.

Multicenter phase II study of apatinib in non-triple-negative metastatic breast cancer

Background

Apatinib is a tyrosine kinase inhibitor targeting vascular endothelial growth factor receptor 2(VEGFR-2). This study was conducted to assess the efficacy and safety of apatinib in patients with non-triple-negative metastatic breast cancer who had received prior chemotherapy for their metastatic disease.

Methods

This multicenter, open-label, single arm study enrolled patients with non-triple-negative breast cancer, pretreated with anthracycline, taxanes and capecitabine, and who failed in the metastatic setting at least 1 and at most 4 prior chemotherapy regimens and at least one endocrine drug for hormone receptor-positive patients as well as at least one anti-Her2 drug for Her2-positive patients. The primary end point of this study was progression free survival (PFS). Secondary end points included objective response rate (ORR), disease control rate (DCR), overall survival (OS), and toxicity. Apatinib was administered as 500 mg daily on days 1 through 28 of each 4-week cycle.

Results

38 patients were enrolled with a median age of 49 years (range, 35 to 62 years) and received apatinib for a median of 4 cycles (range from 0 to 10 cycles). 18 (47.4%) patients experienced dose reduction during treatment. The median relative dose intensity (relative to assigned dose for each cycle) was 82% (range, 45.0% to 100.0%). Median follow-up time was 10.1 months. Median PFS of all 38 patients was 4.0 months (95% confidence interval (CI), 2.8 m – 5.2 m). 36 patients were eligible for efficacy analysis. ORR was 16.7% (6/36). DCR was 66.7% (24/36). Median OS was 10.3 months (95% CI, 9.1 m – 11.6 m). The most common grade 3/4 treatment-related AEs were hypertension (20.5%), hand-foot syndrome (10.3%), and proteinuria (5.1%). Of three possibly drug-related SAEs recorded in the study, 2 (3.4%) deaths occurred within 28 days of last treatment and were both considered to be the result of disease progression. The other one was grade 2 diarrhea needing hospitalization.

Conclusions

Apatinib exhibited objective efficacy in heavily pretreated, metastatic non-triple-negative breast cancer with manageable toxicity, and it might be better to be tested in breast cancer with high angiogenesis dependency.

Trial registration

ClinicalTrials.gov: NCT01653561.

Pathogenetic mechanisms in gastric cancer

Gastric cancer (GC) is a major public health issue as the fourth most common cancer and the second leading cause of cancer-related death. Recent advances have improved our understanding of its molecular pathogenesis, as best exemplified by elucidating the fundamental role of several major signaling pathways and related molecular derangements. Central to these mechanisms are the genetic and epigenetic alterations in these signaling pathways, such as gene mutations, copy number variants, aberrant gene methylation and histone modification, nucleosome positioning, and microRNAs. Some of these genetic/epigenetic alterations represent effective diagnostic and prognostic biomarkers and therapeutic targets for GC. This information has now opened unprecedented opportunities for better understanding of the molecular mechanisms of gastric carcinogenesis and the development of novel therapeutic strategies for this cancer. The pathogenetic mechanisms of GC are the focus of this review.

Chemotherapy or targeted therapy as second-line treatment of advanced gastric cancer. A systematic review and meta-analysis of published studies

Chemotherapy is a cornerstone in treatments of gastric cancer, but despite its benefit, less than 60% of patients receive salvage therapy in clinical practice. We performed a systematic review and meta-analysis based on trial data on the role of second-line treatment of advanced gastric cancer. MEDLINE/PubMed and Cochrane Library were searched for randomized phase III trials that compared active therapy to best supportive care in advanced gastric cancer. Data extraction was conducted according to the PRISMA statement. Summary HR for OS was calculated using a hierarchical Bayesian model and subgroup analysis was performed based on baseline Eastern Cooperative Oncology Group Performance Status (ECOG) performance status (0 vs. 1 or more). A total of 1,407 patients were evaluable for efficacy, 908 were treated in the experimental arms, with chemotherapy (231 pts) or with targeted therapies (677 pts). The risk of death was decreased by 18% (HR = 0.82; 95% CI, 0.79-0.85; posterior probability HR≥1: <0.00001) with active therapies. Chemotherapy and ramucirumab were able to decrease this risk by 27% and 22%, respectively. No differences were found between chemotherapy and ramucirumab. In patients with ECOG = 0 a greater benefit was found for chemotherapy with a reduction of the risk of death by 43% and no benefits were found for ramucirumab or everolimus. In patients with ECOG = 1 or more a significant reduction of the risk of death by 32% was reported in patients treated with ramucirumab, even if no significant difference was reported between chemotherapy and ramucirumab. This analysis reports that active and available therapies are able to prolong survival in patients with advanced gastric cancer with a different outcome based on initial patient's performance status. New trials based on a better patient stratification are awaited.