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Background:Overexpression of p185HER2 is an established poor prognostic factor in breast cancer, portending an aggressive course and potential for early metastasis. On the other hand, monoclonal antibody trastuzumab is widely used in the clinic to target this overexpressed oncogene. Unfortunately, ∼30-40% of all patients overexpressing HER2 respond to trastuzumab, warranting further research regarding the structure and additional modulation of the receptor. In this study, we aimed to investigate the response to trastuzumab in terms of the potential roles of several oncogenic pathways (phosphatase and tensin homologue (PTEN) and phosphatidylinositol 3-kinase (PI3K)) and a truncated receptor protein, p95HER2, retrospectively.Materials and methods:Paraffin-embedded primary tumour tissues of 100 HER2-positive metastatic breast cancer patients who received trastuzumab with combination cytotoxic chemotherapy were analysed with immunohistochemical method for p95HER2, p85 (PI3K) and PTEN. Relationship between variables were tested via χ2, Fischer's exact test and Mann-Whitney U tests, wherever appropriate. Progression-free survival (PFS) and overall survival (OS) periods were calculated with Kaplan-Meier method and survival curves of subgroups were compared with log-rank test.Results:Percentage of patients was found to be 33%, 57% and 42% positive for p95 expression, PTEN and PI3K, respectively. p95-expressing tumours had statistically lower response rates for trastuzumab than tumours not expressing p95 (P=0.001). On the contrary, PTEN-expressing tumours had statistically higher response rates for trastuzumab than tumours not expressing PTEN (P=0.012). PI3K expression had no significant effect on trastuzumab response. Median PFS for p95-expressing and not expressing tumours were 8 months (95% CI, 2.5-13.4 months) and 22 months (95% CI, 9.9-34 months), respectively (P=0.0001). Median PFS for PTEN-expressing and not expressing tumours were 15.3 months (95% CI, 12.6-34 months) and 12.1 months (95% CI, 7.9-16.2 months), respectively (P=0.04). Median OS for p95-expressing and not expressing tumours were 24 months (95% CI, 8.3-40.4 months) and 29.1 months (95% CI, 8.6-43.2 months), respectively (P=0.045). Median OS for PTEN-expressing and not expressing tumours were 25.1 months (95% CI, 7.5-40.1 months) and 26.8 months (95% CI, 8.1-42 months), respectively, which was not statistically significant (P=0.5). Level of PI3K expression had no effect on PFS and OS in our patient population. Presence of visceral metastases HR=2.38 ((95% CI, 1.2-4.5), P=0.009), p95 expression HR=2.1 ((95% CI, 1.1-3.7), P=0.03) and response to trastuzumab HR=2.2 ((95% CI, 1.18-4.47), P=0.014) are identified as factors independently affecting PFS. Response to trastuzumab HR=1.7 ((95% CI, 1.14-3.47), P=0.013) was identified as the single parameter influencing survival by Cox regression analysis.Conclusions:Presence of p95 predicted a poorer response to trastuzumab treatment, shorter PFS and OS in our HER2-positive metastatic breast cancer cohort. In addition, loss of PTEN predicted a poorer response to trastuzumab treatment and shorter PFS but not OS. We could not find an effect of PI3K expression on the above-mentioned parameters. [ABSTRACT FROM AUTHOR]

There are no data regarding the late toxicity of trastuzumab (T) administration with radiotherapy (RT). In this experimental study, we aimed to asses if concurrent or sequential administration of T has any impact for the development of radiation-induced pulmonary fibrosis in rats. Fifty-four female Wistar-albino rats were divided into 6 groups. First group of rats (Group 1; concurrent T) had irradiation to whole thoracic region concurrently with T. Second group (Group 2: sequential T-RT) received thoracic irradiation, 1 week after T. Third group (Group 3: sequential RT-T) had thoracic irradiation first and they had T injection 1 week after RT. Fourth group (Group 4: T only) had only T application. Fifth group (Group 5: RT) had only RT. The last group (Group 6: sham) of rats were observed without any application. A single dose of 12 Gy was given to both lungs with an anterior field at 2 cm depth. T dose which was equivalent to 6 mg/kg adult dose was calculated for each rat, and injected by the tail vein. As an end point the extent of pulmonary fibrosis for each field was graded on a scale from 0 (normal lung or minimal fibrous thickening) to 4 (total fibrous obliteration of the field) at histopathological examination. The mean value of fibrosis scores were 1.44, 1.77, 1.75 and 1.62 for Group 1, 2, 3 and 5, respectively, without any statistically significant differences among them ( P > 0.05). The mean value of fibrosis scores for Group 4 and 6 were 0.25 and 0.33, respectively ( P > 0.05). When the mean value of fibrosis scores of the groups which had RT with or without T, compared with the observation and the T only groups, the difference was significant ( P < 0.05) (one-way ANOVA and Tukey HSD post hoc tests) As a conclusion: addition of T to thoracic irradiation either sequentially or concomitantly did not increase radiation-induced pulmonary fibrosis in rats. [ABSTRACT FROM AUTHOR]

Anemia is a frequent complication of cancer and its treatment. A defect in erythropoietin production has been advocated as being the main cause of anemia in cancer patients. We studied serum erythropoietin levels in 74 patients with solid tumors and in a control group consisting of 20 otherwise healthy individuals without any malignancy, who have only iron deficiency anemia. Serum erythropoietin levels were measured by enzyme immunoassay in cancer patients without anemia (n=34), and in anemic cancer patients (n=40); either receiving chemotherapy (n=21) or not (n=19). Anemic cancer patients were found to have decreased response of erythropoietin for a given hemoglobin level (mean, 40.1+/-34.7 u/ml), compared with the patients having only iron deficiency anemia (mean, 69.7+/-68.6 u/ml) (P<0.05). In patients with iron deficiency anemia having no malignancy, erythropoietin response was remarkably high and inversely correlated with the level of hemoglobin (r=-0.69; P=0. 05). Although there was no correlation between hemoglobin and erythropoietin response in cancer anemia (r=-0.07), serum levels of erythropoietin were found to be higher in anemic cancer patients (mean, 40.1+/-34.7 u/ml), compared with cancer patients with normal hemoglobin values (mean, 19.96+/-18.4 u/ml). There was not any statistically significant difference between erythropoietin levels in anemic cancer patients with or without chemotherapy (mean, 43. 7+/-37.7 u/ml and 41.9+/-30.08 u/ml respectively; P>0.05). No difference in serum erythropoietin levels were noted in patients treated with cisplatin or non-cisplatin containing regimens (mean, 48.36+/-33.12 u/ml and 38.55+/-43.52 u/ml, respectively; P>0.05). In this study, we demonstrated that anemia in cancer patients was caused by blunted erythropoietin response, rather than its quantitative deficiency. Serial measurements, however, should be considered in patients receiving chemotherapy. [ABSTRACT FROM AUTHOR]

This paper presents an experimental technique for measuring internal strains of loaded artificial solids by means of single-strand, strain-gage wires. Specifically, in the present investigation, strain-gage wires were embedded lengthwise within rectangular prisms which were made of either pure-epoxy resin or silica crystals in an epoxy-resin matrix. Several prisms of both types were compressed longitudinally or loaded as simply supported beams. Experimentally measured unidirectional internal strains are compared with theoretically expected values, and agreement between experiment and theory is good. Thus, the validity of this new technique is demonstrated. [ABSTRACT FROM AUTHOR]