Evaluation of EGFR inhibitor-mediated acneiform skin toxicity within the double-blind randomized EVITA trial: A thorough gender-specific analysis using the WoMo score.

Acne-like skin reactions frequently occur in patients undergoing treatment with drugs inhibiting the epidermal growth factor receptor. Recently, the effects of vitamin K1 containing cream (Reconval K1) as prophylactic skin treatment in addition to doxycycline were explored in a double-blind randomized phase II trial (EVITA) in patients with metastatic colorectal cancer receiving cetuximab. EVITA demonstrated a trend towards less severe skin rash in Reconval K1-treated patients using the tripartite WoMo skin reaction grading score as a thorough tool for quantification of drug related skin reactions. This gender-specific analysis of the EVITA trial evaluated the application of the WoMo score for assessment of epidermal growth factor receptor (EGFR)-related skin toxicities according to treatment arm and gender. To show the robustness of results parametric and non-parametric statistical analyses were conducted. All three parts of the WoMo score independently demonstrated the superiority of the treatment arm (Reconval K1) regarding a significant reduction in acneiform skin reactions in women. Men did not benefit from Reconval K1 cream at any time point in none of the WoMo score analyses. The treatment effect in women was confirmed by the use of skin rash categories based on the final WoMo overall score and mixed effect longitudinal multiple linear regression analysis. The WoMo score represents a sensitive tool for studies exploiting treatments against EGFR mediated acne-like skin rash. Part C of the WoMo score seems to be sufficient for quantification of drug related skin toxicities in further studies. Standard WoMo skin reaction score values for future studies are provided.

Use of early tumor shrinkage to predict long-term outcome in metastatic colorectal cancer treated with cetuximab.

PURPOSE: Early tumor shrinkage (ETS) is associated with long-term outcome in patients with chemorefractory metastatic colorectal cancer (mCRC) receiving cetuximab. This association was investigated in the first-line setting in the randomized CRYSTAL and OPUS mCRC trials, after controlling for KRAS tumor mutation status. METHODS: Radiologic assessments at week 8 were used to calculate the relative change in the sum of the longest diameters of the target lesions. Time-dependent receiver operating characteristics provided Cτ-indices (time-dependent c-index). Cox regression models and subpopulation treatment effect pattern plot analysis investigated associations between ETS (radiologic tumor size decrease at week 8) and survival and progression-free survival (PFS). RESULTS: In both trials, in patients with KRAS wild-type mCRC, Cτ values for PFS and survival were higher (P < .001) in those receiving chemotherapy plus cetuximab versus chemotherapy alone, indicating a stronger predictive value of ETS for long-term outcome in these patients. In the CRYSTAL and OPUS trials, respectively, the cutoff value of ETS ≥ 20% (v < 20%) identified patients with KRAS wild-type mCRC receiving chemotherapy plus cetuximab with longer PFS (medians 14.1 v 7.3 months, hazard ratio [HR] = 0.32; P < .001, and medians 11.9 v 5.7 months, HR = 0.22; P < .001) and survival (medians 30.0 v 18.6 months, HR = 0.53; P < .001 and medians 26.0 v 15.7 months, HR = 0.43; P = .006). CONCLUSION: ETS was significantly associated with long-term outcome in patients with KRAS wild-type mCRC treated first-line with chemotherapy plus cetuximab. Validation in prospective trials is required to assess the value of this on-treatment marker in the clinical decision-making process.

A review of the treatment options for skin rash induced by EGFR-targeted therapies: Evidence from randomized clinical trials and a meta-analysis.

BACKGROUND: Agents targeting the epidermal growth factor receptor (EGFR) are amongst the most extensively used of the targeted agents in the therapy of some of the most common solid tumors. Although they avoid many of the classic side effects associated with cytotoxic chemotherapy, they are associated with unpleasant cutaneous toxicities which can affect treatment compliance and impinge on patient quality of life. To date, despite a plethora of consensus recommendations, expert opinions and reviews, there is a paucity of evidence-based guidance for the management of the skin rash that occurs in the treatment of patients receiving EGFR-targeted therapies. METHODS: A literature search was conducted as a first step towards investigating not only an evidence-based approach to the management of skin rash, but also with a view to designing future randomized trials. RESULTS: The literature search identified seven randomized trials and a meta-analysis was conducted using the data from four of these trials involving oral antibiotics. The meta-analysis of the data from these four trials suggests that prophylactic antibiotics might reduce the relative risk of severe rash associated with EGFR-targeted agents by 42-77%. Vitamin K cream was also identified as having a potential role in the management EGFR-targeted agent induced rash. CONCLUSIONS: This review and meta-analysis clearly identify the need for further randomized studies of the role of oral antibiotics in this setting. The results of the ongoing randomized trials of the topical application of vitamin K cream plus or minus doxycycline and employing prophylactic versus reactive strategies are eagerly awaited.

Phase I study of matuzumab in combination with 5-fluorouracil, leucovorin and cisplatin (PLF) in patients with advanced gastric and esophagogastric adenocarcinomas.

BACKGROUND: To evaluate the safety and tolerability of two different weekly doses of the fully humanized epidermal growth factor receptor (EGFR)-targeting monoclonal antibody matuzumab combined with high-dose 5-fluorouracil, leucovorin and cisplatin (PLF) in the first-line treatment of patients with EGFR-positive advanced gastric and esophagogastric adenocarcinomas. METHODS: Patients were treated in two matuzumab dose groups with the first cohort of patients receiving 400 mg matuzumab in combination with PLF. Based on the safety observations the next cohort of patients received 800 mg matuzumab. The study was conducted in two parts, with phase A, designed to assess the safety and tolerability of the combination, and phase B designed to be a treatment continuation for those patients benefiting from treatment. Treatment cycles were 7 weeks each. Each patient received the dose of matuzumab they were assigned to at study entry for the duration of the study. RESULTS: Fifteen EGFR-positive patients were enrolled into the two matuzumab dose groups; 400 mg dose n=7; 800 mg dose n=8. All patients experienced at least one adverse event (AE). No patient experienced any serious AE which was considered to be related to matuzumab. Two grade 3 AEs possibly related to matuzumab occurred in 2 different patients (13.3 %), both in the 800 mg dose group. No dose-limiting toxicity (DLT) was observed in the 400 mg group. The maximum tolerated dose of matuzumab was not reached. The best confirmed overall response rate was 26.7 %. CONCLUSION: Matuzumab, in combination with PLF, demonstrated an acceptable safety profile with modest anti-tumor activity.

Addition of cetuximab to chemotherapy as first-line treatment for KRAS wild-type metastatic colorectal cancer: pooled analysis of the CRYSTAL and OPUS randomised clinical trials.

BACKGROUND: The CRYSTAL and OPUS randomised clinical trials demonstrated that adding cetuximab to first-line chemotherapy in patients with KRAS wild-type metastatic colorectal cancer (mCRC) significantly improved treatment outcome compared with chemotherapy alone. The objective of this pooled analysis was to further investigate these findings in patients with KRAS wild-type tumours using extended survival data and following an enhancement in the ascertainment rate of KRAS and BRAF tumour mutation status from these studies. METHODS: Pooled individual patient data from each study were analysed for overall survival (OS), progression-free survival (PFS) and best overall response rate (ORR) in patients evaluable for KRAS and BRAF mutation status. Treatment arms were compared according to mutation status using log-rank and Cochran-Mantel-Haenszel tests. RESULTS: In 845 patients with KRAS wild-type tumours adding cetuximab to chemotherapy led to a significant improvement in OS (hazard ratio [HR] 0.81; p=0.0062), PFS (HR 0.66; p<0.001) and ORR (odds ratio 2.16; p<0.0001). BRAF mutations were detected in 70/800 evaluable tumours. No significant differences were found in outcome between the treatment groups in these patients. Prognosis was worse in each treatment arm for patients with BRAF tumour mutations compared with those with BRAF wild-type tumours. CONCLUSION: Analysis of pooled data from the CRYSTAL and OPUS studies confirms the consistency of the benefit obtained across all efficacy end-points from adding cetuximab to first-line chemotherapy in patients with KRAS wild-type mCRC. BRAF mutation does not appear to be a predictive biomarker in this setting, but is a marker of poor prognosis.

Down-regulation of CYLD as a trigger for NF-κB activation and a mechanism of apoptotic resistance in hepatocellular carcinoma cells.

The cylindromatosis gene (CYLD) was identified as a tumor suppressor gene, which is mutated in familial cylindromatosis (Brooke-Spiegler syndrome), an autosomal-dominant predisposition to multiple tumors of the skin appendages. CYLD is a deubiquitinating enzyme acting as a negative regulator of the nuclear factor κB (NF-κB) signaling pathway by removing lysine-63-linked polyubiquitin chains from NF-κB activating proteins. In order to investigate the role of CYLD in apoptotic signaling in human hepatocellular carcinoma (HCC) cells, we first studied the expression levels of CYLD in HCC tissues. CYLD expression was lower in HCC both at protein and mRNA levels compared to the surrounding non-malignant tissue. In order to further study the role of CYLD in the apoptotic sensitivity of HCC cells, CYLD was specifically down-regulated in HCC cell lines via RNA interference. The specific down-regulation of CYLD resulted in increased resistance towards treatment with doxorubicin, 5-fluorouracil and cisplatin. In addition, the down-regulation of CYLD in HCC cells decreased the sensitivity towards tumor necrosis factor-α-induced apoptosis. The CYLD knockdown also led to the degradation of the NF-κB inhibitor, IκB-α, resulting in enhanced NF-κB activity in HCC cells. Finally, we found that CYLD expression was triggered by the multikinase inhibitor, sorafenib, by the inhibition of Raf-1, as well as by the blockage of the pro-survival kinases, MEK (U0126) and the epidermal growth factor receptor (AG1478). In summary, we show that CYLD is down-regulated in human HCC and is involved in the apoptotic resistance of HCC cells. Our data identify the reconstitution of CYLD expression as an attractive approach for overcoming resistance to treatment in HCC.

TRAIL-induced apoptosis of hepatocellular carcinoma cells is augmented by targeted therapies.

AIM: To analyze the effect of chemotherapeutic drugs and specific kinase inhibitors, in combination with the death receptor ligand tumor necrosis factor-related apoptosis inducing ligand (TRAIL), on overcoming TRAIL resistance in hepatocellular carcinoma (HCC) and to study the efficacy of agonistic TRAIL antibodies, as well as the commitment of antiapoptotic BCL-2 proteins, in TRAIL-induced apoptosis. METHODS: Surface expression of TRAIL receptors (TRAIL-R1-4) and expression levels of the antiapoptotic BCL-2 proteins MCL-1 and BCL-x(L) were analyzed by flow cytometry and Western blotting, respectively. Knock-down of MCL-1 and BCL-x(L) was performed by transfecting specific small interfering RNAs. HCC cells were treated with kinase inhibitors and chemotherapeutic drugs. Apoptosis induction and cell viability were analyzed via flow cytometry and 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. RESULTS: TRAIL-R1 and -R2 were profoundly expressed on the HCC cell lines Huh7 and Hep-G2. However, treatment of Huh7 and Hep-G2 with TRAIL and agonistic antibodies only induced minor apoptosis rates. Apoptosis resistance towards TRAIL could be considerably reduced by adding the chemotherapeutic drugs 5-fluorouracil and doxorubicin as well as the kinase inhibitors LY294002 [inhibition of phosphoinositol-3-kinase (PI3K)], AG1478 (epidermal growth factor receptor kinase), PD98059 (MEK1), rapamycin (mammalian target of rapamycin) and the multi-kinase inhibitor Sorafenib. Furthermore, the antiapoptotic BCL-2 proteins MCL-1 and BCL-x(L) play a major role in TRAIL resistance: knock-down by RNA interference increased TRAIL-induced apoptosis of HCC cells. Additionally, knock-down of MCL-1 and BCL-x(L) led to a significant sensitization of HCC cells towards inhibition of both c-Jun N-terminal kinase and PI3K. CONCLUSION: Our data identify the blockage of survival kinases, combination with chemotherapeutic drugs and targeting of antiapoptotic BCL-2 proteins as promising ways to overcome TRAIL resistance in HCC.

Bcl-x(L) and Myeloid cell leukaemia-1 contribute to apoptosis resistance of colorectal cancer cells.

AIM: To explore the role of Bcl-x(L) and Myeloid cell leukaemia (Mcl)-1 for the apoptosis resistance of colorectal carcinoma (CRC) cells towards current treatment modalities. METHODS: Bcl-x(L) and Mcl-1 mRNA and protein expression were analyzed in CRC cell lines as well as human CRC tissue by Western blot, quantitative PCR and immunohistochemistry. Bcl-x(L) and Mcl-1 protein expression was knocked down or increased in CRC cell lines by applying specific siRNAs or expression plasmids, respectively. After modulation of protein expression, CRC cells were treated with chemotherapeutic agents, an antagonistic epidermal growth factor receptor (EGFR1) antibody, an EGFR1 tyrosine kinase inhibitor, or with the death receptor ligand TRAIL. Apoptosis induction and cell viability were analyzed. RESULTS: Here we show that in human CRC tissue and various CRC cell lines both Bcl-x(L) and Mcl-1 are expressed. Bcl-x(L) expression was higher in CRC tissue than in surrounding non-malignant tissue, both on protein and mRNA level. Mcl-1 mRNA expression was significantly lower in malignant tissues. However, protein expression was slightly higher. Viability rates of CRC cells were significantly decreased after knock down of Bcl-x(L) expression, and, to a lower extent, after knock down of Mcl-1 expression. Furthermore, cells with reduced Bcl-x(L) or Mcl-1 expression was more sensitive towards oxaliplatin- and irinotecan-induced apoptosis, and in the case of Bcl-x(L) also towards 5-FU-induced apoptosis. On the other hand, upregulation of Bcl-x(L) by transfection of an expression plasmid decreased chemotherapeutic drug-induced apoptosis. EGF treatment clearly induced Bcl-x(L) and Mcl-1 expression in CRC cells. Apoptosis induction upon EGFR1 blockage by cetuximab or PD168393 was increased by inhibiting Mcl-1 and Bcl-x(L) expression. More strikingly, CD95- and TRAIL-induced apoptosis was increased by Bcl-x(L) knock down. CONCLUSION: Our data suggest that Bcl-x(L) and, to a lower extent, Mcl-1, are important anti-apoptotic factors in CRC. Specific downregulation of Bcl-x(L) is a promising approach to sensitize CRC cells towards chemotherapy and targeted therapy.

Phase I trial of cetuximab in combination with capecitabine, weekly irinotecan, and radiotherapy as neoadjuvant therapy for rectal cancer.

PURPOSE: To establish the feasibility and efficacy of chemotherapy with capecitabine, weekly irinotecan, cetuximab, and pelvic radiotherapy for patients with locally advanced rectal cancer. METHODS AND MATERIALS: Twenty patients with rectal cancer (clinical Stage uT3-T4 or N+) received a standard dosing regimen of cetuximab (400 mg/m(2) on Day 1 and 250 mg/m(2) on Days 8, 15, 22, and 29) and escalating doses of irinotecan and capecitabine according to phase I methods: dose level I, irinotecan 40 mg/m(2) on Days 1, 8, 15, 22, and 29 and capecitabine 800 mg/m(2) on Days 1-38; dose level II, irinotecan 40 mg/m(2) and capecitabine 1000 mg/m(2); and dose level III, irinotecan 50 mg/m(2) and capecitabine 1000 mg/m(2). Radiotherapy was given to a dose of 50.4 Gy (45 Gy plus 5.4 Gy). Resection was scheduled 4-5 weeks after termination of chemoradiotherapy. RESULTS: On dose level I, no dose-limiting toxicities occurred; however, Grade 3 diarrhea affected 1 of 6 patients on dose level II. Of 5 patients treated at dose level III, 2 exhibited dose-limiting toxicity (diarrhea in 2 and nausea/vomiting in 1). Therefore, dose level II was determined as the recommended dose for future studies. A total of 10 patients were treated on dose level II and received a mean relative dose intensity of 100% of cetuximab, 94% of irinotecan, and 95% of capecitabine. All patients underwent surgery. Five patients had a pathologically complete remission and six had microfoci of residual tumor only. CONCLUSION: Preoperative chemoradiotherapy with cetuximab, capecitabine, and weekly irinotecan is feasible and well tolerated. The preliminary efficacy is very promising. Larger phase II trials are ongoing.

Investigating the formation and growth of alpha-particle radiation-induced foci of altered hepatocytes: a model-based approach.

The effect of alpha-particle radiation on the formation and increase in volume of preneoplastic liver lesions was investigated in an animal experiment. Mice were divided into four groups; two groups received different doses of the alpha-particle-labeled antibody (213)Bi-anti CD19 ((213)Bi-CD19), Thorotrast was administered to one group, and one group was left untreated. Hematoxylin and eosin-stained liver sections were evaluated for preneoplastic foci of altered hepatocytes 6, 12 and 17 months after treatment. The density and size distribution of focal transections were described by a mechanistic model for the formation and growth of foci of altered hepatocytes. The negative control and the (213)Bi-CD19 groups were combined to investigate the dose-response relationship for model parameters describing the formation and growth of foci of altered hepatocytes. Although (213)Bi-CD19 was given by single injection, the effect on formation of foci of altered hepatocytes lasted for the entire experiment. Likelihood-ratio tests comparing nested models showed that (213)Bi-CD19 increases the rates of both the formation and growth of foci of altered hepatocytes. Comparing the effects of Thorotrast with those of (213)Bi-CD19 revealed that Thorotrast had an effect similar to that of a low dose of (213)Bi-CD19, but the effect on focus formation was slightly smaller whereas the effect on focus growth was slightly higher for Thorotrast, in contrast to a low dose of (213)Bi-CD19.

Treatment of primary glioblastoma multiforme with cetuximab, radiotherapy and temozolomide (GERT)--phase I/II trial: study protocol.

BACKGROUND: The implementation of combined radiochemotherapy (RCHT) with temozolomide (TMZ) has lead to a significant increase in overall survival times in patients with Glioblastoma multiforme (GBM), however, outcome still remains unsatisfactory. The majority of GBMs show an overexpression and/or amplification of the epidermal growth factor receptor (EGFR). Therefore, addition of EGFR-inhibition with cetuximab to the current standard treatment approach with radiotherapy and TMZ seems promising. METHODS/DESIGN: GERT is a one-armed single-center phase I/II trial. In a first step, dose-escalation of TMZ from 50 mg/m2 to 75 mg/m2 together with radiotherapy and cetuximab will be performed. Should safety be proven, the phase II trial will be initiated with the standard dose of 75 mg/m2 of TMZ. Cetuximab will be applied in the standard application dose of 400 mg/m2 in week 1, thereafter at a dose of 250 mg/m2 weekly. A total of 46 patients will be included into this phase I/II trial. Primary endpoints are feasibility and toxicity, secondary endpoints are overall and progression-free survival. An interim analysis will be performed after inclusion of 15 patients into the main study. Patients' enrollment will be performed over a period of 2 years. The observation time will end 2 years after inclusion of the last patient. DISCUSSION: The goal of this study is to evaluate the safety and efficacy of combined RCHT-immunotherapy with TMZ and cetuximab as first-line treatment for patients with primary GBM.