Bariatric surgery-induced weight loss reduces hepatic lipid peroxidation levels and affects hepatic cytochrome P-450 protein content.

OBJECTIVE: To evaluate the effects of surgical weight loss on hepatic lipid peroxidation levels and cytochrome P-450 protein expression in patients with nonalcoholic fatty liver disease (NAFLD). SUMMARY BACKGROUND DATA: NAFLD and nonalcoholic steatohepatitis (NASH) affect hepatic cytochrome P-450 (CYP) protein expression and activity, and CYP2E1 may play a role in the pathogenesis of NAFLD and NASH through induction of oxidative stress and lipid peroxidation. NAFLD and NASH are associated with increased systemic lipid peroxidation levels and elevated hepatic CYP2E1 activity, but hepatic CYP3A4/5 activity is decreased. METHODS: Liver biopsies from 20 patients with NAFLD who underwent bariatric surgery were obtained intraoperatively and at 15 +/- 7 months following surgery. Hepatic malondialdehyde (MDA) levels (a marker of lipid peroxidation), CYP2E1 and CYP3A4/5 protein expression, and steatosis, as a percent of total area, were measured by immunohistochemistry followed by digital image quantitation. RESULTS: Following weight loss, as reflected by reduced BMI (54 +/- 9 vs. 37 +/- 9 kg/m2; P < 0.001), features of the metabolic syndrome, grade and stage of liver disease, and liver histology were all significantly improved (P < 0.01). Hepatic MDA staining (35 +/- 18% vs. 23 +/- 14%; P = 0.02), CYP2E1 protein content (68 +/- 9% vs. 56 +/- 11%; P < 0.001), and steatosis (17 +/- 7% vs. 2 +/- 3%; P < 0.001) were significantly reduced following weight loss. CYP3A4/5 protein content was unchanged (57 +/- 13% vs. 55 +/- 13%; P = 0.433). The reduction in lipid peroxidation was independently associated with changes in CYP2E1 protein expression after bariatric surgery (r = 0.477; P = 0.033). CONCLUSION: Elevations in hepatic lipid peroxidation and CYP2E1 expression that are seen in NAFLD improve significantly with weight loss induced by bariatric surgery.

FOXP3 expression and nodal metastasis of breast cancer.

PURPOSE: T regulatory cells, a subset of T lymphocytes, function to suppress immune responses. FOXP3, a member of the forkhead family of transcription factors, is a good marker for T regulatory cells. Since sentinel nodes are important sites of immunomodulation in breast cancer, we studied the association between T regulatory cells and nodal metastasis using FOXP3 expression in sentinel nodes with and without metastatic breast carcinoma. METHODS: Following sample size calculations, we selected 140 sentinel nodes from breast cancer patients; 70 with metastasis (sentinel node+) and 70 without metastasis (sentinel node-). FOXP3 expression in sentinel nodes was studied by immunohistochemistry. Cortical cells expressing FOXP3 were counted in 10 high power fields. RESULTS: In the evaluable cases, the node positive (n = 66) and negative (n = 69) groups were well balanced for all clinicopathological parameters except histological type. The mean number of T regulatory cells expressing FOXP3 (per 10 hpf) was 139 in the node positive and 132 in the node negative group (P = 0.540). The mean number of T regulatory cells was 162 in patients ≤35 years of age (n = 8) compared to 133 in older patients (P = 0.250). Primary tumor pathological characteristics like tumor type, grade, size, and ER, PR, and HER2 status did not correlate with FOXP3 expression. CONCLUSIONS: The number of FOXP3-expressing T regulatory cells does not differ significantly between sentinel node+ and sentinel node- samples. It was also not affected by primary tumor characteristics like tumor type, grade, size, hormone receptor, and HER2 status.

Apoptosis in spermatocytic and usual seminomas: a light microscopic and immunohistochemical study.

Despite its alarming appearance, spermatocytic seminoma virtually never metastasizes. We hypothesized that this paradox may at least be partially related to increased apoptosis compared to metastasizing germ cell tumors since high expression of proapoptotic factors correlates with indolent behavior in other tumor systems, notably CD30-positive cutaneous lymphoma, another neoplasm where phenotype and behavior do not match. We therefore compared apoptosis and apoptotic regulators in 17 spermatocytic seminomas (2 with sarcoma) and 18 usual seminomas by light microscopy and using immunostains for caspase-3, p53, bcl-2, bcl-xL, FADD, FAS and survivin. We found significantly greater numbers of apoptotic cells and activated caspase-3-positive cells in spermatocytic seminoma compared to usual seminoma (P<0.01). There was over a 10-fold range in apoptotic cells in usual seminoma but only a 4-fold variation in spermatocytic seminoma. Spermatocytic seminoma had decreased p53 expression compared to usual seminoma, with marked variation in bcl-2 expression and increased FADD. The two sarcomas in spermatocytic seminoma, however, showed decreased apoptosis and caspase-3 reactivity, with upregulation of p53 and bcl-2 and decreased FADD expression. We conclude that apoptosis, caspase-3 and FADD expression are increased in spermatocytic seminoma compared to usual seminoma. Apoptotic parameters are decreased in sarcomatous transformation of spermatocytic seminoma. The increased apoptosis of spermatocytic seminoma, possibly mediated by FAS independent activation of the death receptor pathway, may provide some insight into its excellent prognosis. The variation in apoptosis of usual seminomas merits investigation as a prognostic parameter.