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A cat with multiple subcutaneous nodules suggesting a soft tissue sarcoma by physical and computed tomographic examination was diagnosed as being affected by subcutaneous filariosis based on cytologic and ultrasonographic assessments. Nodules were surgically removed and extracted nematodes were identified by PCR as Dirofilaria repens. Furthermore, DNA of Dipetalonema dracunculoides (syn. Acantocheilonema dracunculoides) was detected by PCR, with no evidence of circulating microfilariae. To the best of the authors' knowledge, this represents the first report describing adults of D repens in multiple subcutaneous nodules in a cat. Cytopathologic examination allowed characterization of the parasitic nature of the nodules. Veterinary practitioners should be aware of the possible nodular presentation of D repens in cats and should include D repens in the differential diagnosis of subcutaneous neoformations in the cat.

The occurrence of psychotic symptoms is common in Alzheimer's disease (AD), configuring a possibly distinguished clinical entity defined "Psychosis in Alzheimer's Disease" (AD-P). In order to investigate demographic clinical and biological variables potentially associated to the occurrence of AD-P, 148 AD patients were selected. Mini-Mental State Examination (MMSE), Activities of Daily Living (ADL), and Instrumental Activities of Daily Living (IADL) scores, socio-economic status and 5-HTTLPR and APOE gene polymorphisms were determined for each subject. AD-P patients were significantly more frequent carriers of the long (L) allele of 5-HTTLPR. The percentage of AD-P increased with the number of copies of the L-allele: 13% among S homozygote; 36% among heterozygotes; 51% among L-homozygotes. No difference resulted between AD-P and non-psychotic AD (AD-NP) in the distribution of the epsilon4 allele of APOE. The risk of AD-P was increased in L/L homozygous (OR = 7.25, p = 0.003) and, to a lesser extent, in heterozygous (OR = 3.91; p = 0.018). Backward logistic regression analysis showed that the risk for AD-P was increased in older subjects (OR = 1.07; p = 0.018) while an increase of MMSE score was protective (OR = 0.90; p = 0.004). The occurrence of AD-P resulted significantly related to age at examination, cognitive status, and to the presence of the 5-HTTLPR L-allele.

Gemcitabine is considered the standard first-line therapy for patients with advanced pancreatic cancer. More recent strategies have focused on improving the efficacy of gemcitabine by either improving the method of delivery or by combining gemcitabine with other non-cross-resistant chemotherapy agents or with small-molecule drugs. However, the clinical benefits, response rates, and duration of responses have been modest. Deoxycytidine kinase (dCK) is the rate-limiting enzyme involved in the metabolism of gemcitabine. The expression of dCK has been postulated to be correlative of gemcitabine resistance. We determined the relationship of dCK immunohistochemical protein expression and/or genetic status of dCK in a panel of human pancreatic cancer tissues and pancreatic cancer cell lines and determined the relationship of these variables to the clinical outcome of patients treated with gemcitabine. We report that dCK protein expression is expressed in the majority of pancreatic cancers analyzed (40 of 44 cases, 91%) and showed a range of labeling intensities ranging from 1+ (labeling weaker in intensity than normal lymphocytes present in same section) to 3+ (labeling greater in intensity than normal lymphocytes present in same section). When labeling intensity was compared with survival, low dCK expression (1+ labeling) was correlated with both overall survival (P < 0.009) and progression-free survival following gemcitabine treatment (P < 0.04). Low dCK labeling intensity was also significantly correlated with patient age (70.3 ± 8.1 versus 59.8 ± 7.4 years; P < 0.0006), suggesting that age-related methylation of the dCK gene may account in part for the observed differences. Sequencing of the entire dCK coding sequence in 17 cell lines and 9 patients' cancer tissues with disease progression while on gemcitabine did not identify any mutations, suggesting that genetic alterations of dCK are not a common mechanism of resistance to gemcitabine for this tumor type. Moreover, dCK labeling showed similar patterns and intensities of labeling among matched pretreatment and post-treatment tissues. In summary, pretreatment levels of dCK protein are most correlated with overall survival following gemcitabine treatment and are stable even after resistance to gemcitabine is clinically documented.

The Epidermal Growth Factor Receptor (EGFR) plays a role in multiple tumor cell processes and is targeted by several anticancer therapies. Although EGFR mutations may determine tumor susceptibility in a small proportion of patients, knowledge of the EGFR signaling pathway status in tumors may help guide further drug development and hypothesis-driven combination studies. We aimed to validate and apply a novel computer-aided immunohistochemical (IHC) technique to characterize the status of EGFR signaling in matched colorectal tumor and normal colon tissue samples. Tissue Microarrays (TMA)were made from both cancerous and normal colorectal tissue in 18 patients and stained with antibodies against EGFR, phospho-EGFR (pEGFR), Akt, pAkt, MAPK, and pMAPK. TMA's were quantitatively scored using the Automated Cellular Imaging System (ACIS II, Chromavision, Inc). ACIS was compared against cell line Western blotting, ELISA, and visual scoring (0-3+) by a pathologist. We found that ACIS analysis was highly reproducible and results were well correlated with other techniques. A post-scan "image microdissection" technique of analyzing heterogeneous human samples showed good correlation between paired human samples [Pearson correlation for tumors, 0.922 (p.001)]. Cancer samples had markedly higher staining of pEGFR, Akt, pAkt, MAPK, and pMAPK. We conclude that ACIS IHC of human tissue samples is quantitative, reproducible, and correlates with Western blots and ELISA in cell line pellets as well as pathologist's scores of human samples. Colorectal tumors show higher staining of pEGFR and downstream effectors compared to matched normal colorectal tissues.

To evaluate the immunohistochemical expression of GLUT1, human erythrocyte glucose transporter 1, and fatty acid synthase (FAS), 66 human breast carcinomas and adjacent peritumoral tissue were studied. GLUT1 and FAS were expressed in 53 and 61 carcinomas, in 17 and 14 typical/atypical hyperplastic tissues, and in 16 and 13 tissues adjacent to tumor normal breast tissue, respectively. Statistical analysis revealed association between invasive carcinomas, invasive carcinomas with in situ component and GLUT1 immunostaining. GLUT1 staining was associated with tumor grade, FAS with tumor stage, and GLUT1 and FAS coexpression with tumor grade. Controls expressed no immunostaining. GLUT1 and FAS are new markers involved in the biologic activities of cancer cells. GLUT1 and FAS coexpression may indicate increased use of energy by the neoplastic cells correlated with poorly differentiated features and aggressive behavior. The innovative finding that GLUT1 and FAS are observed in mammary carcinoma adjacent nonneoplastic tissues may suggest a role in detecting initial phases of breast carcinogenesis.

Analysis of gene expression of cancer cell lines exposed to erlotinib, a small molecule inhibitor of the epidermal growth factor receptor (EGFR), showed a marked increase in EGFR mRNA in resistant cell lines but not in susceptible ones. Because cetuximab induces EGFR down-regulation, we explored the hypothesis that treatment with cetuximab would interfere with erlotinib-induced EGFR up-regulation and result in antitumor effects. Exposure of the resistant biliary tract cancer cell line HuCCT1 but not the susceptible A431 epidermoid cell line to erlotinib induced EGFR mRNA and protein expression. Combined treatment with cetuximab blunted the erlotinib-induced EGFR up-regulation and resulted in inhibition of cell proliferation and apoptosis in the HuCCT1 cells. Blockage of erlotinib-induced EGFR synthesis in HuCCT1 cells by small interfering RNA resulted in identical antitumor effects as cetuximab, providing mechanistic specificity. In mice xenografted with A431, HuCCT1, and the pancreatic cancer cell line Panc430, maximal growth arrest and decrease in Ki67 proliferation index were documented with combined therapy, and EGFR down-regulation was observed in cetuximab-treated tumors. These results may indicate that resistance to EGFR kinase inhibition may be, at least in part, mediated by a highly dynamic feedback loop consisting of up-regulation of the EGFR upon exposure to EGFR kinase inhibitors. Abrogation of this response by small interfering RNA-mediated EGFR mRNA down-regulation and/or by cetuximab-mediated protein clearance induced tumor arrest across several cancer models with different EGFR expression levels, suggesting that resistance and sensitivity are dynamic events where proportional decrease in the target rather than absolute content dictates outcome.

We explored the immunohistochemical expression of fatty acid synthase (FAS) in Paget's disease of the vulva (PDV) and its association with clinico-pathological features. FAS is a recently discovered molecule involved in energy supply of normal cells. FAS is also overexpressed in neoplastic tissues because of their increased necessity of energy. Specimens from 20 patients with PDV were immunohistochemically evaluated; increased FAS expression was observed in 7 of 8 patients with invasive PDV (87%), in 3 of 4 patients with microinvasive PDV (75%), and in 1 of 8 patients with noninvasive PDV (12%). Statistical analysis revealed that increased FAS expression was associated with invasive PDV (p = 0.04). To our knowledge, this association of FAS in PDV is the first to be reported in literature. These observations reveal that FAS is a reliable marker of aggressiveness in PDV. The knowledge of FAS statistical association in invasive PDV is an important finding that may stratify these patients in different prognostic groups and determine therapeutic approaches for patient care.

In order to evaluate the prognostic significance of fatty acid synthase (FAS), the key enzyme in fatty acid biosynthesis, in ovarian benign and malignant tumors 98 patients with ovarian masses were immunohistochemically evaluated. Histologic features of the lesions and expression for FAS were statistically associated with clinical data and disease-free survival over a 5-year follow-up period. The mean age of patients was 65 years. TNM surgical stages were I in 31.8%, II in 28.2% and III in 40% of cases. The 5-year disease-free survival of the 85 malignant common epithelial ovarian tumors was 47.1% while 35.3 of patients died with active disease. Seventy-eight (79.6%) out of 98 cases expressed FAS in the neoplastic epithelial cells and 42 (42.9%) in the non-neoplastic stromal cells. Statistical analysis revealed FAS expression and stage of the disease to be significantly correlated to recurrence and survival rates only in the malignant common epithelial tumors. Moreover, multivariate analysis showed FAS expression (p=0.05) and tumor stage (p=0.03) to be independent prognostic predictors. FAS is a reliable predictor of recurrence and disease-free survival in common epithelial ovarian tumors along with neoplastic stage. Clinical data, other histologic subtypes and grading were not statistically significant.