Dalotuzumab in chemorefractory KRAS exon 2 mutant colorectal cancer: Results from a randomised phase II/III trial

Limited data are available on the efficacy of anti-IGF-1R agents in KRAS mutant colorectal cancer (CRC). We analysed the outcome of 69 chemorefractory, KRAS exon 2 mutant CRC patients who were enrolled in a double-blind, randomised, phase II/III study of irinotecan and cetuximab plus dalotuzumab 10 mg/kg once weekly (arm A), dalotuzumab 7.5 mg/kg every second week (arm B) or placebo (arm C). Objective response rate (5.6% vs. 3.1% vs. 4.8%), median progression-free survival (2.7 vs. 2.6 vs. 1.4 months) and overall survival (7.8 vs. 10.3 vs. 7.8 months) were not statistically significantly different between treatment groups. Most common grade ≥3 treatment-related toxicities included neutropenia, diarrhoea, hyperglycaemia, fatigue and dermatitis acneiform. Expression of IGF-1R, IGF-1, IGF-2 and EREG by quantitative real-time polymerase chain reaction was assessed in 351 patients from the same study with available data on KRAS exon 2 mutational status. Median cycle threshold values for all biomarkers were significantly lower (i.e., higher expression, p < 0.05) among patients with KRAS wild-type compared to those with KRAS exon 2 mutant tumours. No significant changes were found according to location of the primary tumour with only a trend towards lower expression of IGF-1 in colon compared to rectal cancers (p = 0.06). Albeit limited by the small sample size, this study does not appear to support a potential role for anti-IGF-1R agents in KRAS exon 2 mutant CRC. Data on IGF-1R, IGF-1 and IGF-2 expression here reported may be useful for patient stratification in future trials with inhibitors of the IGF pathway.ope

Cetuximab and chemotherapy as initial treatment for metastatic colorectal cancer

BACKGROUND: We investigated the efficacy of cetuximab plus irinotecan, fluorouracil, and leucovorin (FOLFIRI) as first-line treatment for metastatic colorectal cancer and sought associations between the mutation status of the KRAS gene in tumors and clinical response to cetuximab. METHODS: We randomly assigned patients with epidermal growth factor receptor-positive colorectal cancer with unresectable metastases to receive FOLFIRI either alone or in combination with cetuximab. The primary end point was progression-free survival. RESULTS: A total of 599 patients received cetuximab plus FOLFIRI, and 599 received FOLFIRI alone. The hazard ratio for progression-free survival in the cetuximab-FOLFIRI group as compared with the FOLFIRI group was 0.85 (95% confidence interval [CI], 0.72 to 0.99; P=0.048). There was no significant difference in the overall survival between the two treatment groups (hazard ratio, 0.93; 95% CI, 0.81 to 1.07; P=0.31). There was a significant interaction between treatment group and KRAS mutation status for tumor response (P=0.03) but not for progression-free survival (P=0.07) or overall survival (P=0.44). The hazard ratio for progression-free survival among patients with wild-type-KRAS tumors was 0.68 (95% CI, 0.50 to 0.94), in favor of the cetuximab-FOLFIRI group. The following grade 3 or 4 adverse events were more frequent with cetuximab plus FOLFIRI than with FOLFIRI alone: skin reactions (which were grade 3 only) (in 19.7% vs. 0.2% of patients, P<0.001), infusion-related reactions (in 2.5% vs. 0%, P<0.001), and diarrhea (in 15.7% vs. 10.5%, P=0.008). CONCLUSIONS: First-line treatment with cetuximab plus FOLFIRI, as compared with FOLFIRI alone, reduced the risk of progression of metastatic colorectal cancer. The benefit of cetuximab was limited to patients with KRAS wild-type tumors.ope

Protection against DNA damage-induced apoptosis by the angiogenic factor thymidine phosphorylase

Thymidine phosphorylase (TP) is involved both in pyrimidine nucleoside metabolism and in angiogenesis. TP also conferred the resistance to hypoxia-induced apoptosis of the cancer cells. In U937 cells, DNA damage-inducing agents significantly enhanced the expression of TP. Cell lines stably transfected with TP cDNA were more resistant to the DNA damage-inducing agents than the mock-transfected cells and showed augmented activity of Akt. The cytoprotective function of TP against DNA damage was independent of its enzymatic activity. The resistance to apoptosis was partially abrogated by treatment with the phosphatidyl inositol 3-kinase (PI3K) inhibitors, suggesting that the cytoprotective function of TP is mediated, at least in part, by regulation of the PI3K/Akt pathway. These findings indicate that TP expression in increased by various stress including DNA damage and that TP molecules confer resistance to DNA damage-induced apoptosis in cancer cells.ope

Different role of functional domains of hTR in DNA binding to telomere and telomerase reconstruction

Even if template sequence of hTR played an essential role in telomere binding, a 326 nucleotide fragment of hTR containing template, pseudoknot, and CR4–5 domains is critical for both binding with telomeric DNA and reconstitution of telomerase activity. A functional study with antisense oligonucleotides suggested that targeted disruption of the template region efficiently abrogated both telomeric DNA binding and telomerase activity, whereas disruption of the CR4–5 region induced only loss of telomerase activity. hTR interacts with telomeric DNA via structural region composed of the template, pseudoknot, and CR4–5 domains, however, each structural domain plays a distinct role in telomere binding and telomerase activity reconstitution.ope

Infusional 5-Fluorouracil, Leucovorin and Docetaxel in Advanced Gastric Cancer

PURPOSE: This study was performed to estimate the response rate and toxicity of a combination chemotherapy, which included infusional 5-Fluorouracil, Leucovorin and Docetaxel in the treatment of patients with an advanced gastric carcinoma. MATERIALS AND METHODS: Twenty two advanced gastric cancer patients, with a bidimensionally measurable or an evaluable disease, were enrolled in this study. The patients received a 5-fluorouracil 1, 000 mg/m2 intravenous (IV) 24 hour infusion (Day 1~3), leucovorin 20 mg/m2 (Day 1~3) and docetaxel 75 mg/m2 intravenously (Day 2) every 3 weeks. RESULTS: The overall response rate was 45.0%. The median duration of response was 10.0 weeks (range: 4~24), the median time to response was 8 weeks (range: 8~20) the median time to progression was 30.0 weeks (95% CI: 16.3~43.2) and the median overall survival duration was 36.0 weeks (95% CI: 1.7~70.2). The median cumulative dose of 5-fluorouracil were 316.2 mg/m2/week and docetaxel was 23.9 mg/m2/week. WHO grade III, IV neutropenia, thromocytopenia and anemia occurred in 50.0%, 4.5% and 4.5% of patients, respectively. There were no occurrence of WHO grade III and IV nausea, vomiting, mucositis, conspitation, diarrhea, or neurotoxicity. CONCLUSION: This chemotherapy regimen, including infusional 5-fluorouracil, leucovorin and docetaxel was an active agent against advanced gastric cancer patients, especially for previous chemotherapy naive patients.ope

Japanese Cancer Association Meeting UICC International Session - What is Cost-effectiveness in Cancer Treatment?

The Japan National Committee for the Union for International Cancer Control (UICC) and UICC-Asia Regional Office (ARO) organized an international session as part of the official program of the 72nd Annual Meeting of the Japanese Cancer Association to discuss the topic "What is cost-effectiveness in cancer treatment?" Healthcare economics are an international concern and a key issue for the UICC. The presenters and participants discussed the question of how limited medical resources can be best used to support life, which is a question that applies to both developing and industrialized countries, given that cancer treatment is putting medical systems under increasing strain. The emergence of advanced yet hugely expensive drugs has prompted discussion on methodologies for Health Technology Assessment (HTA) that seek to quantify cost and effect. The session benefited from the participation of various stakeholders, including representatives of industry, government and academia and three speakers from the Republic of Korea, an Asian country where discussion on HTA methodologies is already advanced. In addition, the session was joined by a representative of National Institute for Health and Care Excellence (NICE) of the United Kingdom, which has pioneered the concept of cost-effectiveness in a medical context. The aim of the session was to advance and deepen understanding of the issue of cost-effectiveness as viewed from medical care systems in different regions.ope

Suppression of peritoneal metastasis by expression of murine endostatin cDNA

Peritoneal seeding is one of problems to be solved in gastrointestinal and ovarian cancers. Angiogenesis is the critical step for a dormancy tumor cluster to be an overt metastatic nodule. However, whether an anti-angiogenesis strategy is effective in the control of peritoneal metastases is still obscure. In this study, we evaluated whether endostatin, an endogenous angiogenesis inhibitor, suppresses peritoneal metastases. MATERIALS AND METHODS: We transduced a human gastric cancer cell line, AGS and a murine renal cancer cell line, Renca, with the plasmid pEndoSTHB, which encodes a secretable form of murine endostatin. Endostatin expression was tested with western blotting, and the biological activity of the secreted endostatin was confirmed with in vitro endothelial cell growth inhibition. In the animal experiments, stable transfectants were injected intraperitoneally. RESULTS: We demonstrated secretion of endostatin from two cell lines transduced with the plasmid pEndoSTHB. Conditioned media secreted from pEndoSTSB-transduced mammalian cells were shown to potently inhibit endothelial cell growth in vitro. We selected stable transfectants with similar in vitro growth rates of their parental cell lines. Significant tumor growth inhibition was observed in the endostatin-expressing Renca cells intraperitoneal injection group at days of 28, compared to the null transfectants intraperitoneal injection control group. CONCLUSION: These results support that peritoneal seeding is angiogenesis-dependant and an anti-angiogenesis strategy is a good way to control peritoneal metastases.ope

Bilateral Breast Cancer: Differential Diagnosis Using Histological and Biological Parameters

BACKGROUND: Contralateral breast cancer is either a metastatic lesion or the second primary cancer. From biological and therapeutic viewpoints, it is important to differentiate metastatic lesions from second primary cancer in bilateral breast cancer. METHODS: Based on Chaudary's histological criteria, we analysed the tumors in 14 and 27 patients with synchronous and metachronous bilateral breast cancers with full histological and biological evaluations. The Nottingham combined histological grade and immunohistochemistry (IHC) for the estrogen receptor, progesterone receptor and cerbB-2 were used. RESULTS: The median age of the patients at first diagnosis was 41 years (range, 26-68 years) and the median time interval between first and second tumors was 34 months (range; 7-209 months) in metachronous cancers. The histopathological type was found in 93% of synchronous cancers and 59% of metachronous cancers (P = 0.02). The concordance rates of T stage and TNM stage were 71 and 64% respectively in synchronous cancers, while they were 24 and 32% respectively in metachronous cancers (P = 0.03). For progesterone receptor status, the concordance rates were 86 and 52% in synchronous and metachronous cancers respectively (P = 0.03). In addition, there was no statistically significant difference in terms of N stage, histological grade, intraductal component, estrogen receptor status, or cerbB-2 expression. CONCLUSION: In spite of the limitation of Chaudary's criteria and the number of patients involved, the combination of histopathological type, T stage and TNM stage shows that synchronous cancers are closer to same clonal lesions (metastatic lesions) than metachronous cancers and that a biomarker, such as progesterone receptor status, plays a role in addition to the histological parameters in differentiating metastatic cancers from second primary cancers.ope

Metastatic Model of Human Gastric Cancer by Orthotopic Transplantation

Purpose: The metastatic animal model of human cancer is important from a practical point of view in the research of cancer metastasis, because it resembles the original tumors morphologically, biologically and biochemically. We developed the animal model to investigate the clinically relevant metastasis of gastric cancer which is the leading cause of death in Korea. Methods: Seven to eight-week-old specific-pathogen-free (SPF) BALB/c-nu mice were used. We developed an orthotopic transplantation model using the tissue obtained from an inoculation of the gastric cancer cell suspension (YCC-3) into a subcutaneous layer of mice. The mice were kept in laminar-flow cabinets under SPF condition and inspected everyday.Results: Mice were sacrificed 8∼12 weeks after the operation when they showed either a measurable mass or signs of distress. The metastatic pattern of this animal model was very similar to that of human gastric cancer. At autopsy, the local growth of the gastric cancer, lymph node metastasis and any distant metastasis were noted. Conclusion: We developed an animal model for human gastric cancer metastasis that will enhance our understanding of the biology of cancer metastasis and it will contribute to the development of the research and treatment of cancer metastasis.ope

An association between RRM1 haplotype and gemcitabine-induced neutropenia in breast cancer patients

PURPOSE: We examined the pattern of single-nucleotide polymorphisms (SNPs) of gemcitabine metabolism-related and target genes in breast cancer patients and evaluated their association with drug response or toxicity. PATIENTS AND METHODS: SNPs in deoxycytidine kinase (dCK), deoxycytidine monophosphate deaminase (DCTD), and ribonucleotide reductase M1 polypeptide (RRM1) were analyzed with genomic DNA of 10 breast cancer cell lines, 74 peripheral blood mononuclear cell (PBMC) samples from advanced breast cancer patients treated with gemcitabine, and 56 PBMC samples from healthy volunteers. RESULTS: The incidences of SNPs of breast cancer patients were 1.4% in dCK (626 A>G), 10.8% in DCTD (315 T>C), 40.5% in the first RRM1 (1082 C>A), 44.6% in the second RRM1 (2455 A>G), 44.6% in the third RRM1 (2464 G>A), and 23% in two RRM1 sites (2455 A>G and 2464 G>A) that were similar to those of the normal control group. We found a double SNP of RRM1 (2455 A>G and 2464 G>A) to be the novel haplotype that was associated with a lower frequency of chemotherapy-induced toxicity, such as neutropenia (p < .01) and G-CSF requirement (p < .005). CONCLUSION: RRM1 haplotype showed an association with susceptibility to gemcitabine monotherapy in breast cancer patients.ope