Relationship between loneliness and proangiogenic cytokines in newly diagnosed tumors of colon and rectum.

OBJECTIVE: To investigate the association of serum levels of proangiogenic cytokines with different indices of social support and loneliness by measuring the levels of expression of two important proangiogenic cytokines, vascular endothelial growth factor (VEGF), and interleukin-6 in tumors of colon and rectum. Lack of social support has been prospectively associated with cancer progression. METHODS: Fifty-one newly diagnosed patients with colorectal tumors (mean age, 68.3 years) completed two measures of loneliness 1 to 2 days before their surgical treatment. The first was an explicit self-report questionnaire, which tapped into negative feelings as a result of low social support. The second was a standardized computer-based task, which measured loneliness implicitly. Immunohistochemical analyses were performed on tumor tissues post surgery to determine the expression of cytokines. RESULTS: Logistic regression showed that higher levels of implicit loneliness independently predicted stronger expression of VEGF, controlling for Dukes stage and explicit loneliness, both of which were nonsignificant predictors. No significant relationships were found between the loneliness measures and interleukin-6. CONCLUSIONS: The results of this study suggest VEGF to be an angiogenic mechanism through which loneliness may lead to worse cancer-related outcomes. Implications are discussed in terms of devising targeted psychosocial and immunotherapeutic interventions for cancer patients with low social support.

CD117/KIT expression in pancreatic adenocarcinoma.

OBJECTIVE: CD117/KIT overexpression is common in neoplasms such as gastrointestinal stromal tumors and predicts clinical response to tyrosine kinase inhibitors. Pancreatic adenocarcinoma has a poor prognosis, and therefore, targeted molecular therapy may be beneficial. Marked differences in the incidence of CD117/KIT expression have been reported in pancreatic adenocarcinoma. The aim of this study was to test the hypothesis that CD117/KIT expression is unusual in pancreatic adenocarcinoma. METHODS: CD117/KIT immunohistochemistry was performed on 23 archival pancreatic adenocarcinoma samples using 2 primary antibodies. RESULTS: Satisfactory internal and external positive control labeling was achieved for both primary antibodies. No tumor cell labeling was identified using one primary antibody, whereas all cases showed cytoplasmic CD117/KIT staining with the second. However, CD117/KIT expression was also identified using the latter within nuclei and benign pancreatic epithelium, suggesting that artifactual staining was occurring. CONCLUSIONS: Pancreatic adenocarcinoma does not express CD117/KIT as assessed using the primary immunohistochemical antibody usually used in our laboratory for CD117/KIT detection. The variation in reported incidence of CD117/KIT expression in pancreatic adenocarcinoma is because of methodological differences in immunohistochemical technique. Ideally, immunohistochemical studies of this molecule should be combined with mutational status testing of the c-kit gene.