HER-2/neu and CD117 (c-kit) overexpression in patients with pesticide exposure and extensive stage small cell lung carcinoma (ESSCLC).

BACKGROUND: The rate of detection of HER-2/neu and CD117 (c-kit) overexpression in small cell lung cancer (SCLC) has varied widely; between 5-35% and 21-70% respectively. METHODS: To evaluate the relationship between pesticide exposure and HER-2/neu and CD117 overexpression in extensive stage SCLC (ESSCLC), we identified patients with ESSCLC and assessed pesticide exposure using a predetermined questionnaire. An exposure index (hours/day x days/year x years) > or = 2400 hours was considered as 'exposed.' HER-2/neu overexpression was evaluated on archival tissue using the DAKO Hercep test, and CD117 testing was performed using immunohistochemistry (A4052 polyclonal antibody). RESULTS: 193 ESSCLC patients were identified. Pesticide exposure data could be obtained on 174 patients (84 females and 109 males) with a mean age of 68.5 years. 53/174 (30.4%) revealed HER-2/neu overexpression. 54/174 (31.03%) specimens showed CD117 overexpression by IHC. On multivariate analysis, HER-2/neu overexpression was associated with diminished survival (p < 0.001). In comparison, CD117 expression did not have an adverse prognostic value (p = 0.025). 41/53 (77.4%) patients with HER-2/neu overexpression and 47/121 (38.8%) patients without overexpression had exposure to pesticides (odds ratio: 5.38; p < 0.01). Among the cohort tested for CD117, 29/54 (53.7%) patients with CD117 overexpression and 59/120 (49.2%) patients without CD117 overexpression had pesticide exposure (odds ratio: 1.18; p = 0.12). CONCLUSION: Pesticide exposure affects HER-2/neu but not CD117 overexpression. Future studies are needed to determine specific pesticide(s)/pesticide components that are responsible for HER-2/neu overexpression in ESSCLC, and to validate our findings in other solid tumors that overexpress HER-2/neu.

Role of her-2/neu overexpression and clinical features at presentation as predictive factors in meningiomas.

Prediction of outcome in patients with meningiomas remains a significant problem to date. We have evaluated the role of symptoms at presentation and overexpression of her-2/neu overexpression as independent prognostic factors in meningiomas. In a retrospective study on patients with biopsy-proven diagnosis of meningioma, her-2/neu overexpression was evaluated using immunohistochemistry (IHC) performed on paraffin-embedded specimens. An IHC score of > or =2+ was considered positive for overexpression. Two hundred thirty-seven patients thus identified between January 1986 and December 1999 included 149 females and 88 males, with a mean age of 63.44 years. Survival was estimated using the Kaplan-Meier method. Incidence of meningiomas in females (62.8%) was significantly greater than in males. Focal neurodeficits, headache, and seizures (39.66%) were the most common presenting complaints and were not related to tumor behavior/outcome. Syncope at presentation was associated with a decreased survival, but this symptom constituted only 2.53% of the total, so reliable conclusions could not be drawn. Only 6 (2.53%) specimens revealed HER-2/neu overexpression by IHC. HER-2/neu overexpression is not a predictor of tumor behavior and has no role as a prognostic factor in meningiomas. Syncope as the clinical presentation at diagnosis may predict a poor outcome, but needs further investigation.

Immunohistochemical determination of HER-2/neu, c-Kit (CD117), and vascular endothelial growth factor (VEGF) overexpression in malignant melanoma.

PURPOSE: To determine the prevalence and evaluate the possible prognostic value of the molecular targets in malignant melanoma, we studied the overexpression of HER-2/neu, c-Kit, and vascular endothelial growth factor (VEGF) in this patient population. MATERIALS AND METHODS: Overexpression of HER-2/neu, c-Kit, and VEGF was evaluated using immunohistochemical assays in 202 archival tissue specimens. RESULTS: Only two patients (0.9%) revealed HER-2/neu overexpression, whereas 46 (22.8%) revealed c-Kit and 42 (20.8%) specimens showed VEGF overexpression. Multivariate analysis performed did not show a significant difference in survival between c-Kit-positive and c-Kit-negative groups (P = 0.36) and VEGF-positive and VEGF-negative groups (P = 0.25). Interestingly, c-Kit was more likely to be overexpressed in the superficial spreading type and VEGF was overexpressed preferentially in the amelanotic melanoma type. CONCLUSIONS: HER-2/neu has no role in melanogenesis. Both c-Kit (expressed in superficial spreading disease) and VEGF (expressed in amelanotic melanoma) may have significant therapeutic implications as molecular targets, which warrants further investigation.

Effect of pesticide exposure on HER-2/neu overexpression seen in patients with extensive stage small cell lung carcinoma.

PURPOSE: The aim of this study was to evaluate the relationship, if any, between pesticide exposure and overexpression of the HER-2/neu oncoprotein in extensive stage small cell lung cancer (ESSCLC). EXPERIMENTAL DESIGN: The records of all patients with a diagnosis of ESSCLC from January 1991 through April 2001 were reviewed in our retrospective study. Pesticide risk (herbicide and insecticide) was assessed by telephone interviews using a predetermined questionnaire with emphasis on type of exposure, use of protective measures, and duration of exposure. An exposure index was calculated (h/day x days/year x years), and patients with an index > 2400 h were considered as exposed. HER-2/neu overexpression was assessed by immunohistochemistry using the Hercep test developed by Dako. Statistical analysis was performed using SPSS-10. RESULTS: A total of 193 patients (84 females and 109 males), with a mean age of 68.5 years (range, 42-90 years) were included in the study. Of these, 57 (29.5%) revealed HER-2/neu overexpression by immunohistochemistry. After adjusting for age, smoking, Eastern Cooperative Oncology Group score, and treatment, HER-2/neu overexpression was associated with a statistically significant diminished survival (P < 0.001; Mann-Whitney U test). We contacted 53 of 57 patients with overexpression and 121 of 136 patients without HER-2/neu overexpression to ascertain a history of pesticide exposure. Forty-one of 53 (77.4%) patients with HER-2/neu overexpression and 47 of the 121 patients without overexpression (38.8%) were exposed to pesticides. We found that patients with history of pesticide exposure had a higher risk of having HER-2/neu overexpression (odds ratio, 5.38; P < 0.01, 95% confidence interval, 2.5-11.2) CONCLUSIONS: HER-2/neu is overexpressed in approximately 30% patients with ESSCLC and is associated with decreased survival. Also, pesticide exposure seems to be related to HER-2/neu overexpression seen in our patient population. Future studies are needed to validate our findings and also to determine which pesticide(s)/pesticide components are actually responsible for HER-2/neu overexpression seen in ESSCLC.

Prevalence of pesticide exposure in young males (

Evidence implicating pesticides as causative agents of prostate cancer is controversial, and specifically, data in young adults is lacking. Hence, we performed a preliminary study evaluating the relationship between pesticide exposure and prostate cancer in young males. After approval from the University of North Dakota Institutional Review Board and Human Subjects Committee, a retrospective study was performed on all young males (2400 hours were considered as 'exposed.' The 2400 hour cut-off value was chosen on the basis of previous reports indicating that this figure represents heavy exposure to genotoxic agents. Statistical analysis was obtained using SPSS-10ledR;. Between 1991 and 2001, 61 young males with adenocarcinoma of the prostate were identified, of whom 56 patients with a mean age of 47 years (range: 40-49) had complete records of treatment and could be contacted for completion of the questionnaire. The most common stage at presentation was Stage III and the mean Gleason's score was 7.5 (range 5-9). Interestingly, almost a third (16/56, 28.6%) of patients had stage IV disease at presentation. 37/56 (66.1%) patients had 'significant' exposure in our study. In addition, interestingly, the mean survival in the subgroup of patients with pesticide exposure was 11.3 months (SD: +/- 2.3 months), while the mean survival in the patients without pesticide exposure (n = 19) was 20.1 months (SD: +/- 3.1 months), with p-value <0.01. Although our study is relatively small, it does reveal preliminary evidence linking pesticide exposure to the early development of, possibly aggressive, prostate adenocarcinoma. Future, larger, epidemiological studies are needed to confirm the findings of our study.