Perioperative chemotherapy with fluorouracil plus leucovorin, oxaliplatin, and docetaxel versus fluorouracil or capecitabine plus cisplatin and epirubicin for locally advanced, resectable gastric or gastro-oesophageal junction adenocarcinoma (FLOT4): a randomised, phase 2/3 trial.

BACKGROUND: Docetaxel-based chemotherapy is effective in metastatic gastric and gastro-oesophageal junction adenocarcinoma. This study reports on the safety and efficacy of the docetaxel-based triplet FLOT (fluorouracil plus leucovorin, oxaliplatin and docetaxel) as a perioperative therapy for patients with locally advanced, resectable tumours. METHODS: In this controlled, open-label, phase 2/3 trial, we randomly assigned 716 patients with histologically-confirmed advanced clinical stage cT2 or higher or nodal positive stage (cN+), or both, resectable tumours, with no evidence of distant metastases, via central interactive web-based-response system, to receive either three pre-operative and three postoperative 3-week cycles of 50 mg/m2 epirubicin and 60 mg/m2 cisplatin on day 1 plus either 200 mg/m2 fluorouracil as continuous intravenous infusion or 1250 mg/m2 capecitabine orally on days 1 to 21 (ECF/ECX; control group) or four preoperative and four postoperative 2-week cycles of 50 mg/m2 docetaxel, 85 mg/m2 oxaliplatin, 200 mg/m2 leucovorin and 2600 mg/m2 fluorouracil as 24-h infusion on day 1 (FLOT; experimental group). The primary outcome of the trial was overall survival (superiority) analysed in the intention-to-treat population. This trial is registered with ClinicalTrials.gov, number NCT01216644. FINDINGS: Between Aug 8, 2010, and Feb 10, 2015, 716 patients were randomly assigned to treatment in 38 German hospitals or with practice-based oncologists. 360 patients were assigned to ECF/ECX and 356 patients to FLOT. Overall survival was increased in the FLOT group compared with the ECF/ECX group (hazard ratio [HR] 0·77; 95% confidence interval [CI; 0.63 to 0·94]; median overall survival, 50 months [38·33 to not reached] vs 35 months [27·35 to 46·26]). The number of patients with related serious adverse events (including those occurring during hospital stay for surgery) was similar in the two groups (96 [27%] in the ECF/ECX group vs 97 [27%] in the FLOT group), as was the number of toxic deaths (two [<1%] in both groups). Hospitalisation for toxicity occurred in 94 patients (26%) in the ECF/ECX group and 89 patients (25%) in the FLOT group. INTERPRETATION: In locally advanced, resectable gastric or gastro-oesophageal junction adenocarcinoma, perioperative FLOT improved overall survival compared with perioperative ECF/ECX. FUNDING: The German Cancer Aid (Deutsche Krebshilfe), Sanofi-Aventis, Chugai, and Stiftung Leben mit Krebs Foundation.

Maintenance strategies after first-line oxaliplatin plus fluoropyrimidine plus bevacizumab for patients with metastatic colorectal cancer (AIO 0207): a randomised, non-inferiority, open-label, phase 3 trial.

BACKGROUND: The definition of a best maintenance strategy following combination chemotherapy plus bevacizumab in metastatic colorectal cancer is unclear. We investigated whether no continuation of therapy or bevacizumab alone are non-inferior to fluoropyrimidine plus bevacizumab, following induction treatment with a fluoropyrimidine plus oxaliplatin plus bevacizumab. METHODS: In this open-label, non-inferiority, randomised phase 3 trial, we included patients aged 18 years or older with histologically confirmed, previously untreated metastatic colorectal cancer, Eastern Cooperative Oncology Group (ECOG) performance status of 0-2, adequate bone marrow, liver, and renal function, no pre-existing neuropathy greater than grade 1, and measurable disease, from 55 hospitals and 51 private practices in Germany. After 24 weeks of induction therapy with either fluorouracil plus leucovorin plus oxaliplatin or capecitabine plus oxaliplatin, both with bevacizumab, patients without disease progression were randomly assigned centrally by fax (1:1:1) to standard maintenance treatment with a fluoropyrimidine plus bevacizumab, bevacizumab alone, or no treatment. Both patients and investigators were aware of treatment assignment. Stratification criteria were response status, termination of oxaliplatin, previous adjuvant treatment with oxaliplatin, and ECOG performance status. At first progression, re-induction with all drugs of the induction treatment was a planned part of the protocol. Time to failure of strategy was the primary endpoint, defined as time from randomisation to second progression after maintenance (and if applicable re-induction), death, or initiation of further treatment including a new drug. Time to failure of strategy was equivalent to time to first progression for patients who did not receive re-induction (for any reason). The boundary for assessment of non-inferiority was upper limit of the one-sided 98·8% CI 1·43. Analyses were done by intention to treat. The study has completed recruitment, but follow-up of participants is ongoing. The trial is registered with ClinicalTrials.gov, number NCT00973609. FINDINGS: Between Sept 17, 2009, and Feb 21, 2013, 837 patients were enrolled and 472 randomised; 158 were randomly assigned to receive fluoropyrimidine plus bevacizumab, 156 to receive bevacizumab monotherapy, and 158 to receive no treatment. Median follow-up from randomisation is 17·0 months (IQR 9·5-25·4). Median time to failure of strategy was 6·9 months (95% CI 6·1-8·5) for the fluoropyrimidine plus bevacizumab group, 6·1 months (5·3-7·4) for the bevacizumab alone group, and 6·4 months (4·8-7·6) for the no treatment group. Bevacizumab alone was non-inferior to standard fluoropyrimidine plus bevacizumab (hazard ratio [HR] 1·08 [95% CI 0·85-1·37]; p=0·53; upper limit of the one-sided 99·8% CI 1·42), whereas no treatment was not (HR 1·26 [0·99-1·60]; p=0·056; upper limit of the one-sided 99·8% CI 1·65). The protocol-defined re-induction after first progression was rarely done (30 [19%] patients in the fluoropyrimidine plus bevacizumab group, 67 [43%] in the bevacizumab monotherapy group, and 73 [46%] in the no treatment group. The most common grade 3 adverse event was sensory neuropathy (21 [13%] of 158 patients in the fluoropyrimidine plus bevacizumab group, 22 [14%] of 156 patients in the bevacizumab alone group, and 12 [8%] of 158 patients in the no treatment group). INTERPRETATION: Although non-inferiority for bevacizumab alone was demonstrated for the primary endpoint, maintenance treatment with a fluoropyrimidine plus bevacizumab may be the preferable option for patients following an induction treatment with a fluoropyrimidine, oxaliplatin, and bevacizumab, as it allows the planned discontinuation of the initial combination without compromising time with controlled disease. Only a few patients were exposed to re-induction treatment, thus deeming the primary endpoint time to failure of strategy non-informative and clinically irrelevant. Progression-free survival and overall survival should be considered primary endpoints in future trials exploring maintenance strategies.

Tumour response and secondary resectability of colorectal liver metastases following neoadjuvant chemotherapy with cetuximab: the CELIM randomised phase 2 trial.

BACKGROUND: Neoadjuvant chemotherapy for unresectable colorectal liver metastases can downsize tumours for curative resection. We assessed the effectiveness of cetuximab combined with chemotherapy in this setting. METHODS: Between Dec 2, 2004, and March 27, 2008, 114 patients were enrolled from 17 centres in Germany and Austria; three patients receiving FOLFOX6 alone were excluded from the analysis. Patients with non-resectable liver metastases (technically non-resectable or > or =5 metastases) were randomly assigned to receive cetuximab with either FOLFOX6 (oxaliplatin, fluorouracil, and folinic acid; group A) or FOLFIRI (irinotecan, fluorouracil, and folinic acid; group B). Randomisation was not blinded, and was stratified by technical resectability and number of metastases, use of PET staging, and EGFR expression status. They were assessed for response every 8 weeks by CT or MRI. A local multidisciplinary team reassessed resectability after 16 weeks, and then every 2 months up to 2 years. Patients with resectable disease were offered liver surgery within 4-6 weeks of the last treatment cycle. The primary endpoint was tumour response assessed by Response Evaluation Criteria In Solid Tumours (RECIST), analysed by modified intention to treat. A retrospective, blinded surgical review of patients with radiological images at both baseline and during treatment was done to assess objectively any changes in resectability. The study is registered with ClinicalTrials.gov, number NCT00153998. FINDINGS: 56 patients were randomly assigned to group A and 55 to group B. One patient in each group were excluded from the analysis of the primary endpoint because they discontinued treatment before first full dose, one patient in group B was excluded because of early pulmonary embolism. A confirmed partial or complete response was noted in 36 (68%) of 53 patients in group A, and 30 (57%) of 53 patients in group B (difference 11%, 95% CI -8 to 30; odds ratio [OR] 1.62, 0.74-3.59; p=0.23). The most frequent grade 3 and 4 toxicities were skin toxicity (15 of 54 patients in group A, and 22 of 55 patients in group B), and neutropenia (13 of 54 patients in group A and 12 of 55 patients in group B). R0 resection was done in 20 (38%) of 53 patients in group A and 16 (30%) of 53 of patients in group B. In a retrospective analysis of response by KRAS status, a partial or complete response was noted in 47 (70%) of 67 patients with KRAS wild-type tumours versus 11 (41%) of 27 patients with KRAS-mutated tumours (OR 3.42, 1.35-8.66; p=0.0080). According to the retrospective review, resectability rates increased from 32% (22 of 68 patients) at baseline to 60% (41 of 68) after chemotherapy (p<0.0001). INTERPRETATION: Chemotherapy with cetuximab yields high response rates compared with historical controls, and leads to significantly increased resectability. FUNDING: Merck-Serono, Sanofi-Aventis, and Pfizer.

Microsatellite instability (MSI-H) is associated with a high immunoscore but not with PD-L1 expression or increased survival in patients (pts.) with metastatic colorectal cancer (mCRC) treated with oxaliplatin (ox) and fluoropyrimidine (FP) with and without bevacizumab (bev): a pooled analysis of the AIO KRK 0207 and RO91 trials.

INTRODUCTION: In a retrospective analysis of two randomized phase III trials in mCRC patients treated first line with oxaliplatin, fluoropyrimidine with and without Bevacizumab (the AIO KRK 0207 and R091 trials) we evaluated the association of high microsatellite instability (MSI-H), immunoscore (IS) and PD-L1 expression in relation to overall survival (OS). METHODS: In total, 550 samples were analysed. Immunohistochemical analysis of the MMR proteins and additionally fragment length analysis was performed, molecular examinations via allele-discriminating PCR in combination with DNA sequencing. Furthermore PD-L1 and IS were assessed. RESULTS: MSI-H tumors were more frequent in right sided tumors (13.66% vs. 4.14%) and were correlated with mutant BRAF (p = 0.0032), but not with KRAS nor NRAS mutations (MT). 3.1% samples were found to be PD-L1 positive, there was no correlation of PDL1 expression with MSI-H status, but in a subgroup analysis of MSI-H tumors the percentage of PD-L1 positive tumors was higher than in MSS tumors (9.75% vs. 2.55%). 8.5% of samples showed a positive IS, MSI-H was associated with a high IS. The mean IS of the pooled population was 0.57 (SD 0.97), while the IS of MSI-H tumors was significantly higher (mean of 2.4; SD 1.4; p =< 0.0001). DISCUSSION: Regarding OS in correlation with MSI-H, PD-L1 and IS status we did not find a significant difference. However, PD-L1 positive mCRC tended to exhibit a longer OS compared to PD-L1 negative cancers (28.9 vs. 22.1 months).

Molecular analysis of the polymorphisms of thymidylate synthase on cell-free circulating DNA in blood of patients with advanced colorectal carcinoma.

As a key enzyme in folate metabolism, the thymidylate synthase (TS) is important for the synthesis of nucleotides. Its polymorphisms may affect the TS gene expression and the susceptibility for Fluoropyrimidine (FU)-based chemotherapies. In this study, we assessed the relationship between the TS genotypes and clinical outcome to 5-FU-based chemotherapy, and examined whether cell-free circulating DNA is applicable for these molecular analyses. We combined the variable number tandem repeat (VNTR) and single nucleotide (SNP) polymorphisms of the TS promoter and the deletion variants (1494del6) in the 3'UTR with the occurrence of loss of heterozygosity (LOH) at the microsatellite markers D18S59, D18S1140, and D18S976 mapped up- and downstream to the TS locus. Cell-free blood DNA, tumor tissues, and leukocytes of 51 patients with advanced colorectal cancer were used. Genotyping revealed linkage disequilibrium between TS promoter and 3'UTR (p = 0.03) in blood and leukocytes. Inverse associations of the response to therapy with the number of polymorphisms (p = 0.05) and the 494del6 polymorphism (p < 0.02) were detected on serum DNA. The quantification of serum DNA showed significant correlations with the 1494del6 variant (p = 0.006) in tumor tissues and the combined polymorphisms in leukocytes (p < 0.04). In contrast to the low LOH frequency in blood, LOH spanned more than one marker in the primary tumor of the majority of the patients suggesting the loss of the entire TS locus. Our data provide insight into the molecular diversity of the regulation of the TS gene expression. This is the first study that compares multi-variant TS genotypes in different clinical specimens.

Graft-versus-host disease prophylaxis with everolimus and tacrolimus is associated with a high incidence of sinusoidal obstruction syndrome and microangiopathy: results of the EVTAC trial.

A calcineurin inhibitor combined with methotrexate is the standard prophylaxis for graft-versus-host disease (GVHD) after allogeneic hematopoietic stem cell transplantation (HSCT). Everolimus, a derivative of sirolimus, seems to mediate antileukemia effects. We report on a combination of everolimus and tacrolimus in 24 patients (median age, 62 years) with either myelodysplastic syndrome (MDS; n = 17) or acute myeloid leukemia (AML; n = 7) undergoing intensive conditioning followed by HSCT from related (n = 4) or unrelated (n = 20) donors. All patients engrafted, and only 1 patient experienced grade IV mucositis. Nine patients (37%) developed acute grade II-IV GVHD, and 11 of 17 evaluable patients (64%) developed chronic extensive GVHD. Transplantation-associated microangiopathy (TMA) occurred in 7 patients (29%), with 2 cases of acute renal failure. The study was terminated prematurely because an additional 6 patients (25%) developed sinusoidal obstruction syndrome (SOS), which was fatal in 2 cases. With a median follow-up of 26 months, the 2-year overall survival rate was 47%. Although this new combination appears to be effective as a prophylactic regimen for acute GVHD, the incidence of TMA and SOS is considerably higher than seen with other regimens.

Prediction of efficacy and side effects of chemotherapy in colorectal cancer.

Treatment of gastrointestinal cancers has significantly advanced over the last several years with the introduction of effective chemotherapeutic and targeted drugs. Providing individual treatment with low toxicity but maximum benefit is still an unsolved problem. Inter-individual variation of drug toxicity and efficacy is mainly determined by genetic polymorphisms. The genetic approach of pharmacogenetics and pharmacogenomics is developing as a valuable tool to design tailored therapy. This review focuses on clinically significant polymorphisms in genes involved in metabolism of chemotherapy used in gastrointestinal cancer: fluoropyrimidines, irinotecan, and platinum. In addition, the first results of pharmacogenetics in targeted therapy including cetuximab and bevacizumab are discussed.

Pharmacogenetic analysis of liver toxicity after busulfan/cyclophosphamide-based allogeneic hematopoietic stem cell transplantation.

UNLABELLED: THE AIM of this study was to evaluate the impact of genomic polymorphisms of methylene-tetrahydrofolate-reductase (MTHFR-C677T, MTHFR-A1298C) and various glutathione S-transferases (GSTP1-Ilel05Val, GSTA1*a/b, GSTM1, GSTT1) on the occurrence of liver toxicity in patients receiving allogeneic hematopoietic stem cell transplantation (HSCT). PATIENTS AND METHODS: Eighty-four adult patients were enrolled in this retrospective study. All patients were treated with busulfan/cyclophosphamide as a conditioning regimen and received cyclosporine and short-course MTX for GvHD prophylaxis. Genotyping was performed using PCR based restriction-fragment-length-polymorphism (RFLP) techniques. RESULTS: Multivariate analysis identified the MTHFR-A1298C polymorphism as an independent predictor for maximum levels of bilirubin (p=0.0025) and duration of hyperbilirubinaemia (p=0.013). Furthermore, there was an association between this polymorphism and the occurrence of the sinusoidal obstruction syndrome (SOS) (p=0.048). No significant associations between the MTHFR-C677T or the various GST polymorphisms and liver toxicity were observed. CONCLUSION: The MTHFR-A1298C polymorphism might be associated with liver toxicity in patients receiving allogeneic HSCT.

Effect of Neoadjuvant Chemotherapy Followed by Surgical Resection on Survival in Patients With Limited Metastatic Gastric or Gastroesophageal Junction Cancer: The AIO-FLOT3 Trial.

IMPORTANCE: Surgical resection has a potential benefit for patients with metastatic adenocarcinoma of the stomach and gastroesophageal junction. OBJECTIVE: To evaluate outcome in patients with limited metastatic disease who receive chemotherapy first and proceed to surgical resection. DESIGN, SETTING, AND PARTICIPANTS: The AIO-FLOT3 (Arbeitsgemeinschaft Internistische Onkologie-fluorouracil, leucovorin, oxaliplatin, and docetaxel) trial is a prospective, phase 2 trial of 252 patients with resectable or metastatic gastric or gastroesophageal junction adenocarcinoma. Patients were enrolled from 52 cancer care centers in Germany between February 1, 2009, and January 31, 2010, and stratified to 1 of 3 groups: resectable (arm A), limited metastatic (arm B), or extensive metastatic (arm C). Data cutoff was January 2012, and the analysis was performed in March 2013. INTERVENTIONS: Patients in arm A received 4 preoperative cycles of fluorouracil, leucovorin, oxaliplatin, and docetaxel (FLOT) followed by surgery and 4 postoperative cycles. Patients in arm B received at least 4 cycles of neoadjuvant FLOT and proceeded to surgical resection if restaging (using computed tomography and magnetic resonance imaging) showed a chance of margin-free (R0) resection of the primary tumor and at least a macroscopic complete resection of the metastatic lesions. Patients in arm C were offered FLOT chemotherapy and surgery only if required for palliation. Patients received a median (range) of 8 (1-15) cycles of FLOT. MAIN OUTCOMES AND MEASURES: The primary end point was overall survival. RESULTS: In total, 238 of 252 patients (94.4%) were eligible to participate. The median (range) age of participants was 66 (36-79) years in arm A (n = 51), 63 (28-79) years in arm B (n = 60), and 65 (23-83) years in arm C (n = 127). Patients in arm B (n = 60) had only retroperitoneal lymph node involvement (27 patients [45%]), liver involvement (11 [18.3%]), lung involvement (10 [16.7%]), localized peritoneal involvement (4 [6.7%]), or other (8 [13.3%]) incurable sites. Median overall survival was 22.9 months (95% CI, 16.5 to upper level not achieved) for arm B, compared with 10.7 months (95% CI, 9.1-12.8) for arm C (hazard ratio, 0.37; 95% CI, 0.25-0.55) (P < .001). The response rate for arm B was 60% (complete, 10%; partial, 50%), which is higher than the 43.3% for arm C. In arm B, 36 of 60 patients (60%) proceeded to surgery. The median overall survival was 31.3 months (95% CI, 18.9-upper level not achieved) for patients who proceeded to surgery and 15.9 months (95% CI, 7.1-22.9) for the other patients. CONCLUSIONS AND RELEVANCE: Patients with limited metastatic disease who received neoadjuvant chemotherapy and proceeded to surgery showed a favorable survival. The AIO-FLOT3 trial provides a rationale for further randomized clinical trials. TRIAL REGISTRATION: clinicaltrials.gov identifier: NCT00849615.

Association between glutathione S-transferase P1, T1, and M1 genetic polymorphism and survival of patients with metastatic colorectal cancer.

BACKGROUND: Members of the glutathione S-transferase (GST) superfamily are important in cellular defense mechanisms. These enzymes attach reduced glutathione to electrophilic groups in a wide variety of toxic compounds, including chemotherapeutic agents. Certain polymorphisms in GSTs are associated with changes in enzyme activity, sensitivity to chemotherapy, and overall patient survival. In a retrospective study, we investigated associations between common polymorphisms in genes for several GST subclasses (GSTP1, GSTT1, GSTM1) and survival of patients with metastatic colorectal cancer receiving 5-fluorouracil (5-FU)/oxaliplatin chemotherapy. METHODS: During 1998-2000, 107 previously treated patients with advanced colorectal cancer received 5-FU/oxaliplatin combination chemotherapy. Associations between deletion polymorphisms in GSTM1 and GSTT1 genes and between a polymorphism in the GSTP1 gene that generates an Ile(105)Val in the GSTP1 protein and survival were evaluated using relative risks (RRs) of dying and the log-rank test. All statistical tests were two-sided. RESULTS: Patients heterozygous for the GSTP1 polymorphism had an RR = 0.47 (95% confidence interval [CI] = 0.27 to 0.81) compared with patients homozygous for the GSTP1 (105)Ile allele. Patients homozygous for the mutant polymorphism had an RR = 0.16 (95% CI = 0.04 to 0.63). After adjustment for performance status and tumor site, the stratified RRs were 0.28 (95% CI = 0.07 to 1.10) for patients with two (105)Val alleles and 0.64 (95% CI = 0.36 to 1.16) for those with one (105)Val allele (P =.042). Patients with the (105)Val/(105)Val genotype survived a median of 24.9 months, those with the (105)Ile/(105)Ile genotype a median of 7.9 months, and those with the (105)Ile/(105)Val genotype a median of 13.3 months (P<.001). The GSTM1 and GSTT1 genotypes were not associated with survival or clinical response. CONCLUSIONS: The GSTP1 Ile(105)Val polymorphism is associated in a dose-dependent fashion with increased survival of patients with advanced colorectal cancer receiving 5-FU/oxaliplatin chemotherapy.

A novel single nucleotide polymorphism within the 5' tandem repeat polymorphism of the thymidylate synthase gene abolishes USF-1 binding and alters transcriptional activity.

Thymidylate synthase (TS) gene expression is modulated by a polymorphism in the 5' regulatory region of the gene. The polymorphism consists mainly of either two repeats (2R) or three repeats (3R) of a 28-bp sequence, yielding greater TS gene expression and protein levels with a 3R genotype. Two USF family E-box consensus elements are found within the tandem repeats of the 3R genotype, and one is found within the 2R genotype. These elements bind USF proteins in vitro by electrophoretic mobility shift analysis and in vivo by chromatin immunoprecipitation assay. We show that the additional USF consensus element within the 3R construct confers greater transcriptional activity relative to the 2R construct. Mutagenesis of the USF sites shows that the transcriptional regulation of TS is dependent, in part, on USF proteins binding within the tandem repeats. In addition, we identified a novel G-->C single nucleotide polymorphism in the second repeat of 3R alleles within the USF consensus element that alters the ability of USF proteins to bind and thus alters the transcriptional activation of TS gene constructs bearing this genotype. Through RFLP analysis, we determined the respective frequencies of the C allele (3RC) among all 3R alleles in non-Hispanic whites, Hispanic whites, African Americans, and Singapore Chinese to be 56%, 47%, 28%, and 37%, respectively. Based on our findings, this novel single nucleotide polymorphism should be considered when the 5' tandem repeat polymorphism is being used as a predictor of clinical outcome to TS inhibitors.

Gene polymorphisms of epidermal growth factor receptor and its downstream effector, interleukin-8, predict oxaliplatin efficacy in patients with advanced colorectal cancer.

BACKGROUND: Researchers have recently reported an association between the epidermal growth factor receptor (EGFR) pathway and platinum-chemotherapy sensitivity in cancer patients. The (CA)(n) repeat polymorphism in intron 1 of the EGFR gene has been identified and found to alter EGFR expression in vitro as well as in vivo. A higher number of these CA repeats is associated with lower EGFR levels, whereas a low number of repeats is associated with higher EGFR levels. A second key polymorphism within the EGFR pathway (HER1 R497K) is a single nucleotide change (G-A) in codon 497 of the EGFR gene, which leads to an arginine-lysine substitution in the extracellular domain of subdomain IV. Furthermore, interleukin-8 (IL-8), recently identified as an EGFR downstream effector, plays a vital role in tumor angiogenesis and progression. Three other polymorphisms, each related to the IL-8 gene, have also been identified as playing a pivotal role in the EGFR pathway: T-251A in the promoter region of the IL-8 gene, G+2607C in exon 2 of the IL-8 receptor CXCR1 gene, and C+785T in exon 11 of the IL-8 receptor CXCR2 gene. PATIENTS AND METHODS: In this study, we employed a 5'-end 33P-gATP-labeled polymerase chain reaction (PCR) protocol as well as the PCR-restriction fragment length polymorphism method in order to determine the genotypes for the previously mentioned polymorphisms in 105 patients with metastatic colorectal cancer. Tests were conducted to establish whether these polymorphisms could predict clinical outcome to 5-flourouracil/oxaliplatin chemotherapy. RESULTS: Among all patients assessed, those possessing < 20 EGFR CA repeats were more likely to show disease progression than were patients with >or= 20 CA repeats (P = 0.019; log-rank test). Also, patients with the CXCR1 GC genotype were found to have an increased relative risk of time to tumor progression that was 1.55 (95% CI, 0.8-3.0) times that of patients with the homozygous GG genotype (P = 0.17; log-rank test). CONCLUSION: Overall, our data suggest that gene polymorphisms active in the EGFR pathway may be associated with the sensitivity of colorectal cancer patients to platinum-based chemotherapy.

Tailoring chemotherapy in advanced colorectal cancer.

In this post-genomic era, the individualization of chemotherapy through the study of pharmacogenetics is becoming an ever attainable reality. Keys to individual variations in drug response and toxicity are being identified through the study of drug targets, metabolizing enzymes, efflux and DNA repair systems at the genomic, mRNA and protein levels. Several promising pharmacogenetic candidates with predictive and/or prognostic value have been identified. These candidates, along with others yet to be identified, could in the near future allow for the tailoring of therapy with an ever increasing chemotherapeutic armamentarium. Well-designed and large prospective analyses, which include relevant pharmacogenetic parameters, are needed to confirm the initial clinical associations reported thus far.

CHAMP: A Phase II Study of Panitumumab With Pemetrexed and Cisplatin Versus Pemetrexed and Cisplatin in the Treatment of Patients With Advanced-Stage Primary Nonsquamous Non-Small-Cell Lung Cancer With Particular Regard to the KRAS Status.

INTRODUCTION: The aim of the study was to investigate the efficacy and tolerability of panitumumab, a fully human antiepidermal growth factor receptor monoclonal antibody, in combination with pemetrexed/cisplatin in patients with stage IIIB to IV primary nonsquamous non-small-cell lung cancer and wild type V-Ki-ras2 Kirsten rat sarcoma viral oncogene homolog (KRAS). Results were compared with those obtained in a control group of patients who received a pemetrexed/cisplatin regimen only. PATIENTS AND METHODS: This was a phase II, randomized, open-label study with 2 treatment arms. In total, 96 patients received panitumumab at a dose of 9 mg/kg in combination with pemetrexed 500 mg/m(2) and cisplatin 75 mg/m(2) (n = 49) or pemetrexed/cisplatin alone (n = 47). The primary outcome measure was progression-free survival at 6 months. Secondary end points of the study included overall survival, tumor response, quality of life, and safety outcomes. The CHAMP study is registered with ClinicalTrials.gov, number NCT01088620. RESULTS: Progression-free survival at 6 months did not indicate a benefit of panitumumab as a supplement to the standard therapy of pemetrexed/cisplatin whereas the overall survival showed a clear difference between the treatment groups in favor of the standard therapy. Results might be affected by the higher rates of serious adverse events and higher death rates within the panitumumab arm. CONCLUSIONS: Results from the present study indicate that combination of cisplatin/pemetrexed with panitumumab should not be recommended for patients with adenocarcinoma and KRAS wild type because of lack of efficacy, lack of improvement of quality of life, and because of the increase in toxicity rates compared with patients in the control arm, who received standard chemotherapy of pemetrexed/cisplatin.

A 6 bp polymorphism in the thymidylate synthase gene causes message instability and is associated with decreased intratumoral TS mRNA levels.

OBJECTIVE: A 6 bp deletion polymorphism in the thymidylate synthase (TS) gene was investigated in order to determine its function. METHODS: A luciferase system was used to investigate the function of the 6 bp/1494 polymorphism in vitro. A group of 43 patients with colorectal carcinoma were evaluated for the 6 bp/1494 polymorphism and for intratumoral TS mRNA levels in vivo. RESULTS: The 3'UTR of TS containing the +6 bp polymorphism resulted in an approximate 35% decrease in luciferase activity and mRNA levels, while the TS-3'UTR bearing the -6 bp deletion resulted in an approximate 70% decrease in luciferase activity and mRNA levels. The TS-3'UTR construct containing the -6 bp/1494 deletion also had a higher rate of message degradation compared to the +6 bp/1494 construct. Individuals homozygous for the insertion (+6 bp/+6 bp) had significantly higher TS mRNA levels compared to individuals that were homozygous for the deletion (-6 bp/-6 bp) (P < 0.007). We determined the frequency of the -6 bp/1494 deletion polymorphism to be 41% in non-Hispanic whites, 26% in Hispanic whites, 52% in African-Americans and 76% in Singapore Chinese. CONCLUSIONS: These results suggest that the -6 bp/1494 deletion polymorphism in the 3'UTR of TS is associated with decreased mRNA stability in vitro and lower intratumoral TS expression in vivo. Further, the 6 bp/1494 polymorphism varies greatly within different ethnic populations and is in linkage disequilibrium with the TS 5' tandem repeat enhancer polymorphism. Taken together, these data suggest that the 6 bp/1494 polymorphism may be a useful screening tool in predicting TS mRNA expression.

Cyclooxygenase-2 inhibitors in colorectal cancer.

Cyclooxygenase (COX) enzyme-dependent arachidonic acid metabolites occupy key positions in important physiologic processes such as immunity, reproduction, and vascular integrity. Large retrospective and prospective population-based studies have shown that the use of both nonselective, nonsteroidal anti-inflammatory drugs and selective COX-2 inhibitors are associated with decreased colorectal cancer incidence and mortality rate. A majority of animal studies provide strong evidence that prevention of intestinal tumors is more efficiently accomplished by COX-2 selective inhibition rather than by COX-1 suppression. The inducible COX-2 isoform is overexpressed in colorectal tissues and is associated with critical events of tumorigenesis. COX-2 expression correlates with expression of angiogenic factors and new blood vessel formation. Inhibition of COX-2 favors apoptosis and causes a dose-dependent decline of tumor growth and metastasis in these models. These data, together with the fact that COX-2 inhibitors cause less toxic side effects compared with nonselective nonsteroidal anti-inflammatory drugs, render these new compounds promising candidates in chemoprevention and treatment of colorectal cancer. Results from initial clinical trials suggest that COX-2 inhibitors may be able to reduce the polyp burden in patients with familial polyposis coli. However, further clinical studies are needed to evaluate whether COX-2 inhibition will be effective in all types of colorectal tumor tissues. This is especially true for neoplastic lesions that express COX-2 at a lower level (eg, hereditary nonpolyposis colorectal cancer) and for colorectal tumors of patients with inflammatory bowel disease. In summary, COX-2 inhibitors represent a new and very promising group of chemotherapeutic agents with great potential for both colorectal cancer prevention and treatment.

Implications of genetic testing in the management of colorectal cancer.

The prognosis of patients with colorectal cancer is impacted by various factors at the time of diagnosis, including location of the tumor, gender, age and overall performance status of the patient. Optimal postoperative management of patients who have undergone successful tumor resection involves the utilization of reliable determninants of prognosis to help select patients who would benefit from adjuvant treatment, while sparing others from drug-related adverse effects. Tailoring chemotherapy for patients with disseminated cancer, or for patients who receive adjuvant chemotherapy, is also critical. Interpatient differences in tumor response and drug toxicity are common during chemotherapy. Genomic variability of key metabolic enzyme complexes, drug targets, and drug transport molecules is an important contributing factor. The identification of genetic markers of response and prognosis will aid in the development of more individualized chemotherapuetic strategies for cancer patients. Potential prognostic indicators in colorectal cancer include oncogenes, tumor suppressor genes, genes involved in angiogenic and apoptotic pathways and cell proliferation, and those encoding targets of chemotherapy. Specifically, molecular markers such as deletion of 18q (DCC), p27 and microsatellite instability are promising as indicators of good or poor prognosis. Molecular determinants of efficacy and host toxicity of the most commonly used drugs in colorectal cancer, fluoracil, irinotecan and oxaliplatin, are being investigated. Alterations in gene expression, protein expression and polymorphic variants in genes encoding thymidylate synthase, dihydropyrimidine dehydrogenase, dUTP nucleotidehydrolase and thymidine phosphorylase (for fluoropyrimidine-based chemotherapy), uridine diphosphate glucosyltransferase (UGT) 1A1 and carboxylesterase (for irinotecan therapy), and excision repair cross-complementing genes (ERCC1 and ERCC2) and glutathione-S-transferase P1 (for oxalilplatin-based regimens) may be useful as markers for clinical drug response, survival and host toxicity.

Pharmacogenetic aspects in treatment of colorectal cancer--an update.

Pharmacogenomic analyses will become crucial to predict patients' toxicity to treatment and will also help to predict the tumor response. Processes of drug metabolism, drug efflux, DNA-repair and characteristics of drug targets are critical checkpoints of drug efficacy. These crucial pathways for drug action have been part of pharmacogenomic studies evaluating the impact of genomic variants on transcription, translation, protein structure and substrate binding of the genes involved. Promising candidates have been identified with predictive value for response and toxicity to chemotherapy in colorectal cancers. These candidates need to be incorporated into large, prospective clinical trials to confirm their impact for response and survival to chemotherapy that has been reported in retrospective analyses. Confirmed predictive markers, together with additional yet to be identified pharmacogenomic key players, will provide the basis for tailoring chemotherapy in the future.

The -9Ala/-9Val polymorphism in the mitochondrial targeting sequence of the manganese superoxide dismutase gene (MnSOD) is associated with age among Hispanics with colorectal carcinoma.

Recently a T to C substitution in the mitochondrial targeting sequence of the manganese superoxide dismutase (MnSOD) gene was observed that changes the amino acid sequence of the protein from valine (V) to alanine (A) and is associated with a decreased defense capacity against oxidative stress. We investigated whether this polymorphism of the MnSOD gene is associated with increased risk for colorectal cancer among Hispanics and non-Hispanic whites. All controls (63 Hispanic, 58 non-Hispanic) and colorectal cancer cases (64 Hispanic, 61 non-Hispanic) were genotyped using a fluorogenic 5'-nuclease assay. The observed alanine frequency was 0.62 among disease-free Hispanics and 0.51 among non-Hispanic whites controls. No significant differences were observed between cancer patients and disease-free controls in either ethnic group (p=0.90) excluding this polymorphism as a risk factor for colorectal cancer in Hispanics and non-Hispanic whites. Among Hispanic individuals with colorectal cancer the alanine allele was observed more frequently in young patients. Patients homozygous for the alanine allele (24/64) showed a mean age of 37.6 years compared to 42.3 years for heterozygotes (29/64) and 48.4 years for patients homozygous for the V allele (p=0.045, ANOVA). The data demonstrate that the -9Val/-9Ala substitution is more common in Hispanics than in non-Hispanic whites. Furthermore, the data suggest that the alanine allele of this polymorphism may be associated with an increased risk to develop colorectal cancer at a young age in Hispanics.

ERCC1 gene polymorphism as a predictor for clinical outcome in advanced colorectal cancer patients treated with platinum-based chemotherapy.

Excision repair cross-complementation group 1 (ERCC1) is a highly conserved protein and an essential member of the nucleotide excision repair pathway. DNA repair is an important mechanism for resistance to platinum-based chemotherapy. Previous studies have shown that ERCC1 gene expression is associated with clinical outcome to platinum chemotherapy in a variety of cancers. Recently, 2 common polymorphisms in the ERCC1 gene have been described. The first is a single nucleotide polymorphism at codon 188 of the ERCC1 gene that causes a C-->T change but codes for the same amino acid, asparagine. This polymorphism may be associated with differential ERCC1 gene expression. The second is also a signal nucleotide polymorphism in the 3'-untranslated region and may affect MRNA stability. We hypothesized that these 2 polymorphisms may be associated with clinical outcome to platinum-based chemotherapy. We assessed the relationship between these ERCC1 gene polymorphism and clinical outcome to platinum-based chemotherapy in 106 patients with advanced refractory colorectal cancer. We found a significant associated between the ERCC1 codon 118 polymorphism and clinical outcome. Patients with the C/C genotype had a median survival of 15.3 months (95% CI, 6.0-12.1) and 11.1 months (95% CI, 5.8-16.2) for those with C/T and T/T genotypes, respectively. The ERCC1 codon 118 polymorphism may be a useful predictor of clinical outcome in advanced colorectal cancer patients treated with platinum-based chemotherapy.