A phase II Study Evaluating Combined Neoadjuvant Cetuximab and Chemotherapy Followed by Chemoradiotherapy and Concomitant Cetuximab in Locoregional Oesophageal Cancer Patients.

BACKGROUND: Pre-operative chemoradiotherapy using a 5-fluorouracil (5-FU)/cisplatin backbone is widely used to improve surgical outcomes in locoregional oesophageal cancer patients, despite a non-negligible failure rate. OBJECTIVE: We evaluated intensification of this approach to improve patient outcomes by adding cetuximab to induction 5-FU/cisplatin/docetaxel (TPF) and to chemoradiotherapy in a phase II study. PATIENTS AND METHODS: Between November 2006 and April 2009, 50 patients with stage II-IVa squamous cell carcinoma (SCC) or adenocarcinoma of the oesophagus or gastro-oesophageal junction initiated three TPF/cetuximab cycles. Six weeks later, patients with response or stabilisation initiated 6 weeks of cisplatin/cetuximab/radiotherapy, followed by surgery. The primary objective was the clinical complete response (cCR) rate after induction therapy plus chemoradiotherapy in intent-to-treat patients. RESULTS: Thirty-eight patients were evaluable after chemoradiotherapy, 84% of whom showed disease control. Six patients (12%) achieved a cCR, with a 54% overall response rate. Twenty-seven patients underwent surgery, 11 of whom (22%; nine SCC, two adenocarcinoma) had a pathological CR (41%). Fifteen patients were alive after a median follow-up of 23.2 months. Median progression-free survival was 12.2 months (95% confidence interval [CI] 1.7-22.8). Median overall survival was 23.4 months (95% CI 12.2-36.6) and was significantly longer among the 22 patients with complete resection than in the five patients without (42.1 vs. 24.9 months; p = 0.02, hazard ratio: 3.6, 95% CI 1.1-11.6). The toxicity profile was acceptable. CONCLUSIONS: Neoadjuvant cetuximab/TPF followed by chemoradiotherapy in locoregional oesophageal carcinoma patients is feasible and offers a modest response rate in this trial. The results of combining trimodality neoadjuvant treatment with cetuximab are consistent with the literature. Registration: The study is registered at ClinicalTrials.gov (NCT00733889).

Correction to: A Phase II Study Evaluating Combined Neoadjuvant Cetuximab and Chemotherapy Followed by Chemoradiotherapy and Concomitant Cetuximab in Locoregional Oesophageal Cancer Patients.

Errors were subsequently identified in the article and the following corrections should be noted.

Targeting STAT3 with silibinin to improve cancer therapeutics.

Signal transducer and activator of transcription 3 (STAT3) has a prominent role in mediating resistance to conventional chemo-/radio-therapies and modern targeted drugs. While a number of STAT3 inhibitors have been shown to enhance the efficacy of therapeutic agents in vitro, the majority of them have yet to enter clinical evaluation mostly because of lack of efficacy issues. Silibinin is the main component of the silymarin complex, a standardized extract obtained from the seeds of the milk thistle herb Silybum marianum. This review summarizes current evidence supporting the ability of silibinin to function as a natural down-modulator of STAT3 activity. We examine the reported capacity of silibinin to reduce the toxicity of cancer treatments and to reverse tumor cell resistance via STAT3 inhibition. We also briefly review our clinical data in cancer patients treated with oral nutraceutical products containing silibinin. The beneficial effects of silibinin might accelerate the design of strategies aimed to overcome and prevent the emergence of STAT3-mediated cancer drug resistance in clinical settings.

EphA2 receptor activation with ephrin-A1 ligand restores cetuximab efficacy in NRAS-mutant colorectal cancer cells.

Patients with wild-type KRAS metastatic colorectal cancer (mCRC) that harbors NRAS activating mutations do not benefit from anti-EGFR therapies. Very little is known about oncogenic NRAS signaling driving mCRC unresponsiveness to the EGFR-directed antibody cetuximab. Using a system of paired NRAS-mutant and wild-type isogenic mCRC cell lines to explore signaling pathways engaged by the common oncogenic NRAS Q61K variant upon challenge with cetuximab, we uncovered an unexpected mechanism of resistance to cetuximab involving dysregulation of the ephrin-A1/EphA2 signaling axis. Parental NRAS+/+ cells, but not NRASQ61K/+ cells, activated the ephrin receptor ephA1 in response to cetuximab treatment. Moreover, whereas cetuximab treatment significantly downregulated EPHA2 gene expression in NRAS+/+ cells, EPHA2 expression in NRASQ61K/+ cells was refractory to cetuximab. Remarkably, pharmacologically mimicked ephrin-A1 engagement to ephA2 converted NRAS-mutant into RAS wild-type mCRC cells in terms of cetuximab efficacy. Accordingly, activation of the ephA2 receptor by bioactive recombinant human ephrin-A1/Fc-fusion protein suppressed the cetuximab-unresponsive hyperactivation of MAPK and AKT and fully restored cetuximab activity in NRAS-mutant colorectal cells. Collectively, these findings reveal that the clinical benefit of cetuximab in mCRC might necessarily involve the suppression of the ligandless oncogenic signaling of the ephA2 receptor. Hence, ligand-dependent tumor suppressor signaling using therapeutic ephA2 agonists might offer new therapeutic opportunities to clinically widen the use of cetuximab in NRAS-mutated and/or ephA2-dependent mCRC tumors.

Synthetic lethal interaction of cetuximab with MEK1/2 inhibition in NRAS-mutant metastatic colorectal cancer.

KRAS mutations are an established predictor of lack of response to EGFR-targeted therapies in patients with metastatic colorectal cancer (mCRC). However, little is known about the role of the rarer NRAS mutations as a mechanism of primary resistance to the anti-EGFR monoclonal antibody cetuximab in wild-type KRAS mCRC. Using isogenic mCRC cells with a heterozygous knock-in of the NRAS activating mutation Q61K, we aimed to elucidate the mechanism(s) by which mutant NRAS blocks cetuximab from inhibiting mCRC growth. NRASQ61K/+ cells were refractory to cetuximab-induced growth inhibition. Pathway-oriented proteome profiling revealed that cetuximab-unresponsive ERK1/2 phosphorylation was the sole biomarker distinguishing cetuximab-refractory NRASQ61K/+ from cetuximab-sensitive NRAS+/+ cells. We therefore employed four representative MEK1/2 inhibitors (binimetinib, trametinib, selumetinib, and pimasertib) to evaluate the therapeutic value of MEK/ERK signaling in cetuximab-refractory NRAS mutation-induced mCRC. Co-treatment with an ineffective dose of cetuximab augmented, up to more than 1,300-fold, the cytotoxic effects of pimasertib against NRASQ61K/+ cells. Simultaneous combination of MEK1/2 inhibitors with cetuximab resulted in extremely high and dose-dependent synthetic lethal effects, which were executed, at least in part, by exacerbated apoptotic cell death. Dynamic monitoring of real-time cell growth rates confirmed that cetuximab synergistically sensitized NRASQ61K/+ cellsto MEK1/2 inhibition. Our discovery of a synthetic lethal interaction of cetuximab in combination with MEK1/2 inhibition for the NRAS mutant subgroup of mCRC underscores the importance of therapeutic intervention both in the MEK-ERK and EGFR pathways to achieve maximal therapeutic efficacy against NRAS-mutant mCRC tumors.

Capecitabine and irinotecan with bevacizumab 2-weekly for metastatic colorectal cancer: the phase II AVAXIRI study.

BACKGROUND: The optimal sequence of chemotherapeutic agents is not firmly established for the treatment of metastatic colorectal cancer (mCRC). This phase II multi-centre study investigated the efficacy and tolerability of a standard capecitabine plus irinotecan (XELIRI) regimen with bevacizumab in previously untreated patients with mCRC. METHODS: Patients received intravenous irinotecan 175 mg/m(2) on day 1 and oral capecitabine 1000 mg/m(2) (800 mg/m(2) for patients >65 years of age) twice daily on days 2-8, followed by a 1-week rest, and bevacizumab 5 mg/kg as an intravenous infusion on day 1 every 2 weeks. RESULTS: Seventy-seven patients were included in the intention-to-treat and safety populations. Progression-free survival at 9 months was 61%. The overall response and disease control rates were 51% and 84%, respectively. Median progression-free and overall survival times were 11.9 and 24.8 months, respectively. 48 patients (62%) had at least one grade 3/4 adverse event, the most common being asthenia, diarrhoea and neutropenia. Quality of life varied little over the study period with mean visual analogue scale general health scores ranging from 71 to 76 over cycles 1-11. CONCLUSION: Our study found irinotecan and capecitabine administered fortnightly with bevacizumab in patients with mCRC to be an effective and tolerable regimen. TRIAL REGISTRATION: clinicaltrials.gov identifier NCT00875771. Trial registration date: 04/02/2009.

Discovery and validation of an INflammatory PROtein-driven GAstric cancer Signature (INPROGAS) using antibody microarray-based oncoproteomics.

This study aimed to improve gastric cancer (GC) diagnosis by identifying and validating an INflammatory PROtein-driven GAstric cancer Signature (hereafter INPROGAS) using low-cost affinity proteomics. The detection of 120 cytokines, 43 angiogenic factors, 41 growth factors, 40 inflammatory factors and 10 metalloproteinases was performed using commercially available human antibody microarray-based arrays. We identified 21 inflammation-related proteins (INPROGAS) with significant differences in expression between GC tissues and normal gastric mucosa in a discovery cohort of matched pairs (n=10) of tumor/normal gastric tissues. Ingenuity pathway analysis confirmed the "inflammatory response", "cellular movement" and "immune cell trafficking" as the most overrepresented biofunctions within INPROGAS. Using an expanded independent validation cohort (n = 22), INPROGAS classified gastric samples as "GC" or "non-GC" with a sensitivity of 82% (95% CI 59-94) and a specificity of 73% (95% CI 49-89). The positive predictive value and negative predictive value in this validation cohort were 75% (95% CI 53-90) and 80% (95% CI 56-94), respectively. The positive predictive value and negative predictive value in this validation cohort were 75% (95% CI 53-90) and 80% (95% CI 56-94), respectively. Antibody microarray analyses of the GC-associated inflammatory proteome identified a 21-protein INPROGAS that accurately discriminated GC from noncancerous gastric mucosa.

Oxaliplatin in combination with infusional 5-fluorouracil as first-line chemotherapy for elderly patients with metastatic colorectal cancer: a phase II study of the Spanish Cooperative Group for the Treatment of Digestive Tumors.

BACKGROUND: We previously reported a 35% overall response rate (ORR) with biweekly 5-fluorouracil (5-FU) continuous infusion (TTD [Spanish Cooperative Group for Digestive Tumour Therapy] schedule) plus irinotecan as first-line therapy in elderly patients with metastatic colorectal cancer (mCRC). The present study also was carried out in elderly patients to determine the efficacy and safety of the same 5-FU schedule plus oxaliplatin. PATIENTS AND METHODS: Patients (aged ≥72 years old) with mCRC, measurable disease, ECOG (Eastern Cooperative Oncology Group) ≤2, and no prior treatment were treated with oxaliplatin 85 mg/m(2) plus 5-FU 3000 mg/m(2) as a 48-hour infusion every 2 weeks. RESULTS: The study included 134 patients, of whom, 129 were eligible. The main comorbidities were hypertension (44%), diabetes (17%), and chronic obstructive pulmonary disease (11%). The ORR and disease control rate (ORR plus stable disease) were 52% and 80%, respectively. With a median follow-up of 14 months, the median progression-free survival and overall survival were 9.1 and 16.3 months, respectively. The most frequent grade 3/4 adverse events included neutropenia (16%), diarrhea (11%), and grade 3 neurotoxicity (18%). No correlation was found between efficacy or safety and comorbidities. CONCLUSIONS: To our knowledge, this is the largest phase II prospective study in elderly patients with mCRC. The observed efficacy and safety of this schedule compared favorably with those reported in this population, including regimens with monoclonal antibodies.

Transcriptional upregulation of HER2 expression in the absence of HER2 gene amplification results in cetuximab resistance that is reversed by trastuzumab treatment.

The recent identification of HER2 gene amplification as a novel predictor of resistance to the EGFR (HER2)-targeted antibody cetuximab and of response to combination therapies against EGFR and HER2 in wild-type KRAS tumor settings may represent a further step toward personalized medicine for patients with colorectal cancer. Herein, we show that transcriptional upregulation of HER2 expression in the absence of HER2 gene amplification is a molecular phenomenon that takes place in EGFR-dependent, wild-type KRAS squamous cell carcinoma (SCC) cells that acquire resistance to cetuximab. Since cetuximab activity against cetuximab-refractory SCC cells can be fully restored in the presence of the anti-HER2 monoclonal antibody trastuzumab, our findings suggest that, beyond HER2 gene amplification, we might need to redefine the threshold values for HER2 positivity to improve the accuracy of the selection of cetuximab-refractory patients with wild-type KRAS that may benefit from receiving a cetuximab/trastuzumab combination.

Evolution of the predictive markers amphiregulin and epiregulin mRNAs during long-term cetuximab treatment of KRAS wild-type tumor cells.

Molecular mechanisms other than activating KRAS mutations should underlie the occurrence of weaker versus stronger responses to cetuximab (CTX) in EGFR-dependent carcinomas with either an intact KRAS signaling or in which KRAS mutations do not predict CTX efficacy. We hypothesized that KRAS wild-type (WT) tumor cell-line models chronically adapted to grow in the presence of CTX could be interrogated to establish if the positive predictive value of the mRNAs coding for the EGFR ligands amphiregulin (AR) and epiregulin (EPI) could be significantly altered during and/or after treatment with CTX. Gene expression analyses using real-time (kinetic) RT-PCR were performed to monitor the transcriptional evolution of EGFR ligands EGF, TGFα, AR, BTC, EPI, NRG and HB-EGF in experimental modes induced to exhibit acquired resistance to the mono-HER1 inhibitor CTX, the mono-HER2 inhibitor trastuzumab (Tzb) or the dual HER1/HER2 inhibitor lapatinib (LPT). Gene expression signatures for EGFR ligands distinctively related to the occurrence of unresponsiveness to CTX, Tzb or LPT, with minimal overlap between them. CTX's molecular functioning largely depended on the overproduction of the mRNAs coding for the EGFR ligands AR and EPI. Thus, a dramatic down-regulation of AR/EPI mRNA expression occurred upon loss of CTX efficacy in EGFR-positive tumor cells with an intact regulation of RAS signaling. Unlike KRAS mutations, which are informative of unresponsiveness to CTX solely in mCRC, our hypothesis-generating data suggest that expression status of AR and EPI mRNAs might be evaluated as dynamic predictors of response in KRAS WT patients receiving any CTX-based therapy.

Interferon/STAT1 and neuregulin signaling pathways are exploratory biomarkers of cetuximab (Erbitux®) efficacy in KRAS wild-type squamous carcinomas: a pathway-based analysis of whole human-genome microarray data from cetuximab-adapted tumor cell-line models.

KRAS mutation status is being used as the sole biomarker to predict therapeutic efficacy of cetuximab in metastatic colorectal cancer (mCRC). A significant number of mCRC patients with KRAS wild-type (WT) tumors, however, do not benefit from cetuximab. We are also lacking efficacy predictors in head and neck squamous cell carcinomas with an intact KRAS signaling and in non-small cell lung cancer in which KRAS mutations do not predict cetuximab efficacy. We recently established pre-clinical models of EGFR gene-amplified KRAS WT A431 squamous carcinoma cells chronically adapted to grow in the presence of cetuximab. We employed the ingenuity pathway analysis software to functionally interpret data from Agilent's whole human genome arrays in the context of biological processes, networks, and pathways. Cetuximab-induced activation of the interferon (IFN)/STAT1 appeared to switch from 'growth inhibitory' in acutely-treated cells to 'pro-survival' in chronically-adapted cells. Cetuximab treatment appeared to negatively select initially dominant IFN-sensitive clones and promoted selection of IFN- and cetuximab-refractory tumor clones constitutively bearing an up-regulated IFN/STAT1 signaling. High-levels of mRNAs coding for the EGFR ligands amphiregulin (AREG), epiregulin (EREG), and neuregulin-1/heregulin (NRG1) predicted for acute cetuximab's functioning. Chronic cetuximab, however, appeared to negatively select initially dominant AREG/EREG/NRG1-positive clones to promote selection of cetuximab-refractory clones exhibiting a knocked-down neuregulin signaling. Our current evolutionary mapping of the transcriptomic changes that occur during cetuximab-induced chronic blockade of EGFR/KRAS WT signaling strongly suggests that mRNAs coding for IFN/STAT1- and EGFR ligands-related genes can be evaluated as novel predictors of efficacy in KRAS WT squamous cancer patients being treated with cetuximab.

Phase II study of trastuzumab and cisplatin as first-line therapy in patients with HER2-positive advanced gastric or gastroesophageal junction cancer.

INTRODUCTION: HER2 over-expression and/or amplification are present in 9-38% of gastric or gastroesophageal junction (GEJ) cancers and are correlated to poor outcome. We conducted a multicentre phase II trial to evaluate trastuzumab in combination with cisplatin in patients with untreated HER2-positive advanced gastric or GEJ cancer. MATERIALS AND METHODS: Chemo-naïve patients with measurable, non-resectable, advanced or metastatic gastric or GEJ adenocarcinoma, with HER2 over-expression and/or amplification (IHC 3+, or IHC 2+ and FISH+), age ≥18 years, ECOG ≤2, left ventricle ejection fraction ≥50% and adequate organ function were eligible. Treatment consisted of trastuzumab (8 mg/kg on cycle 1 day 1 as loading; 6 mg/kg in subsequent cycles) and cisplatin (75 mg/m(2)), both intravenously on day 1, every 21 days. RESULTS: Twenty-two out of 228 patients (10%) were HER2- positive and were included in this phase II trial. The median age was 66 years and ECOG 0/1 was 41%/59%. The median number of cycles was 4 (range 1-41). The confirmed ORR was 32% and disease control was achieved in 64% of patients. Median time to progression was 5.1 months. Grade 3 adverse events included asthenia (27%), neutropenia (18%), anorexia (14%), diarrhoea (9%) and abdominal pain (9%). There were no grade 4 toxicities or treatment-related deaths. Higher baseline HER extracellular domain (ECD) levels were associated with better outcome in terms of response and survival. CONCLUSIONS: Trastuzumab in combination with cisplatin is an active regimen and has a favourable toxicity profile in advanced HER2-positive gastric or gastroesophageal cancers.

Stem cell property epithelial-to-mesenchymal transition is a core transcriptional network for predicting cetuximab (Erbitux™) efficacy in KRAS wild-type tumor cells.

Beyond a well-recognized effect of KRAS mutations in determining de novo inefficacy of cetuximab (CTX) in metastatic colorectal cancer, we urgently need a biomarker signature for predicting CTX efficacy in KRAS wild-type (WT) tumors. CTX-adapted EGFR gene-amplified KRAS WT tumor cell populations were induced by stepwise-chronic exposure of A431 epidermoid cancer cells to CTX. Genome-wide analyses of 44K Agilent's whole human arrays were bioinformatically evaluated by Gene Set Enrichment Analysis (GSEA)-based screening of the KEGG pathway database. Molecular functioning of CTX was found to depend on: (i) The occurrence of a positive feedback loop on Epidermal Growth Factor Receptor (EGFR) activation driven by genes coding for EGFR ligands (e.g., amphiregulin); (ii) the lack of a negative feedback on mitogen-activated protein kinase (MAPK) activation regulated by dual-specificity phosphatases (e.g., DUSP6) and; (iii) the transcriptional status of gene pathways controlling the epithelial-to-mesenchymal transition (EMT) and its reversal (MET) program (actin cytoskeleton and cell-cell communication-e.g., keratins-focal adhesion signaling-e.g., integrins-and EMT-inducing cytokines - e.g., transforming growth factor-ß). Quantitative real-time PCR, high-content immunostaining, and flow-cytometry analyses confirmed that CTX efficacy depends on its ability to promote: (i) Stronger cell-cell contacts by up-regulating the expression of the epithelial markers E-cadherin and occludin; (ii) down-regulation of the epithelial transcriptional repressors Zeb, Snail, and Slug accompanied by restoration of cortical F-actin; and (iii) complete prevention of the CD44(pos)/CD24(neg/low) mesenchymal immunophenotype. The impact of EGFR ligands/MAPK phosphatases gene transcripts in predicting CTX efficacy in KRAS WT tumors may be tightly linked with the ability of CTX to concurrently reverse the EMT status, a pivotal property of migrating cancer stem cells.

Elderly patients with advanced colorectal cancer derive similar benefit without excessive toxicity after first-line chemotherapy with oxaliplatin-based combinations: comparative outcomes from the 03-TTD-01 phase III study.

PURPOSE: Healthy elderly patients with metastatic colorectal cancer may benefit from chemotherapy as much as the younger population. This analysis compares the outcomes of first-line oxaliplatin plus fluoropyrimidines in elderly versus young patients. PATIENTS AND METHODS: 348 patients were randomized to capecitabine 1000 mg/(m2 12 h), days 1-14 plus oxaliplatin 130 mg/m2 day 1, every 3 weeks or weekly infusional 5-FU 2250 mg/m2 over 48 h plus bimonthly oxaliplatin 85 mg/m2. We evaluated response rate, time to progression, overall survival and toxicity according to age. RESULTS: ORR for elderly and young patients were 34.9% and 44.7%, respectively (p=0.081). Median TTP did not differ between the two groups: 8.3 months for patients > or =70 years and 9.6 months for those <70 years (p=0.114). Median OS was 16.8 months and 20.5 months for the > or =70 and <70 years groups, respectively (p=0.74). With XELOX, mild paresthesia and an increase in transaminase levels were more frequent for young patients, whereas grade 3/4 diarrhea was higher in those > or =70 years (25% vs. 8%, p=0.005). For FUOX, only paresthesia was significantly lower in patients > or =70 years (53% vs. 71%, p=0.032). CONCLUSION: Elderly patients with MCRC benefit from first-line oxaliplatin-fluoropyrimidine combinations as much as younger patients, without increased toxicity.

Phase III study of capecitabine plus oxaliplatin compared with continuous-infusion fluorouracil plus oxaliplatin as first-line therapy in metastatic colorectal cancer: final report of the Spanish Cooperative Group for the Treatment of Digestive Tumors Trial.

PURPOSE: The aim of this phase III trial was to compare the efficacy and safety of capecitabine plus oxaliplatin (XELOX) versus Spanish-based continuous-infusion high-dose fluorouracil (FU) plus oxaliplatin (FUOX) regimens as first-line therapy for metastatic colorectal cancer (MCRC). PATIENTS AND METHODS: A total of 348 patients were randomly assigned to receive XELOX (oral capecitabine 1,000 mg/m2 bid for 14 days plus oxaliplatin 130 mg/m2 on day 1 every 3 weeks) or FUOX (continuous-infusion FU 2,250 mg/m2 during 48 hours on days 1, 8, 15, 22, 29, and 36 plus oxaliplatin 85 mg/m2 on days 1, 15, and 29 every 6 weeks). RESULTS: There were no significant differences in efficacy between XELOX and FUOX arms, which showed, respectively, median time to tumor progression (TTP; 8.9 v 9.5 months; P = .153); median overall survival (18.1 v 20.8 months; P = .145); and confirmed response rate (RR; 37% v 46%; P = .539). The safety profile of the two regimens was similar, although there were lower rates of grade 3/4 diarrhea (14% v 24%) and grade 1/2 stomatitis (28% v 43%), and higher rates of grade 1/2 hyperbilirubinemia (37% v 21%) and grade 1/2 hand-foot syndrome (14% v 5%) with XELOX versus FUOX, respectively. CONCLUSION: This randomized study shows a similar TTP of XELOX compared with FUOX in the first-line treatment of MCRC, although there was a trend for slightly lower RR and survival. XELOX can be considered as an alternative to FUOX.