The association among HER2, MET and FOXP3 expression and tumor regression grading in gastric adenocarcinoma.

Although the introduction of the perioperative chemotherapy on the management of gastric cancer has improved patients survival, heterogeneity of clinical outcomes has been evidenced in parallel to different histopathological regression pattern of gastric cancer cells. Thus, this study evaluated the tumor regression grading (TRG) in a series of post-treatment gastric tumors and its associations with HER2, MET, and FOXP3 expression. Material of 54 gastric cancer samples was available for TRG evaluation and immunohistochemistry. We found that total and subtotal pathologic response were significantly associated to the intestinal subtype (p = 0.04) and that well-differentiated tumors were significantly correlated with total or partial response (p = 0.019). Although not associated with the TRG, FOXP3 expression in gastric tumors was associated to poorly differentiated tumors (p = 0.03), to the diffuse and mixed subtypes together (p = 0.04) and to the presence of vascular infiltration (p = 0.04), while HER2 overexpression was associated to better differentiated cases (p = 0.04) and to the absence of vascular infiltration (p = 0.02). MET expression, however, showed no association with the analyzed clinicopathological factors. This study highlights the role of tissue differentiation on pathological response to neoadjuvant chemotherapy in gastric cancer and shows no impact between FOXP3, HER2 and MET expression in terms of TRG.

Is c-Met oncoprotein expression an adverse prognosticator in extrahepatic bile duct cancer treated with curative resection followed by adjuvant chemoradiotherapy?

PURPOSE: To analyze the expression of c-Met, and to investigate correlations between the expression of c-Met, clinicopathologic variables, and survival in patients undergoing curative surgery followed by adjuvant chemoradiotherapy for extrahepatic bile duct (EHBD) cancer. METHODS: Ninety EHBD cancer patients who underwent curative resection followed by adjuvant chemoradiotherapy were enrolled. Expression of c-Met was assessed with immunohistochemical staining on tissue microarray. The correlation between clinicopathologic variables and survival outcomes was evaluated using Kaplan-Meier method and Cox proportional hazard model. RESULTS: On univariate analysis, 66 patients (76.7 %) showed c-Met expression. c-Met expression had a significant impact on 5-year overall survival (OS) (43.0 % in c-Met(+) vs. 25.0 % in c-Met(-), p = 0.0324), but not on loco-regional relapse-free survival or distant metastasis-free survival (DMFS). However, on multivariate analysis incorporating tumor location and nodal involvement, survival difference was not maintained (p = 0.2940). Tumor location was the only independent prognostic factor predicting OS (p = 0.0089). Hilar location tumors, nodal involvement, and poorly differentiated tumors were all identified as independent prognostic factors predicting inferior DMFS (p = 0.0030, 0.0013, and 0.0037, respectively). CONCLUSIONS: This study showed that c-Met expression was not associated with survival outcomes in EHBD cancer patients undergoing curative resection followed by adjuvant chemoradiotherapy. Further studies are needed to fully elucidate the prognostic value of c-Met expression in these patients.

Study of growth factors and receptors in carcinoma ex pleomorphic adenoma.

Carcinoma ex pleomorphic adenoma (CXPA) is a rare malignant salivary gland tumor derived from a pre-existing pleomorphic adenoma. It is a good model to study the evolution of carcinogenesis, starting with in situ areas to frankly invasive carcinoma. Growth factors are associated with several biological and neoplastic processes by transmembrane receptors. In order to investigate, by immunohistochemistry, the expression of some growth factors and its receptors [EGF receptor, fibroblast growth factor, fibroblast growth factor receptor 1, fibroblast growth factor receptor 2, hepatocyte growth factor, c-Met, transforming growth factor (TGF) beta1, TGFbetaR-II and insulin-like growth factor receptor 1] in the progression of CXPA, we have used ten cases of CXPA in several degrees of invasion- intracapsular, minimally and frankly invasive carcinoma- with only epithelial component. Slides were qualitatively and semi-quantitatively evaluated according to the percentage of stained tumor cells from 0 to 3 (0 = less than 10%; 1 = 10-25%; 2 = 25-50%; 3 = more than 50% of cells). Malignant epithelial cells starting with in situ areas showed stronger expression than luminal cells of pleomorphic adenoma for all antibodies. Most of the intracapsular, minimally and frankly invasive CXPA presented score 3. However, score 2 was more evident in the frankly invasive one. In small nests of invasive carcinoma, negative cells were observed probably indicating that the proliferative process is replaced by the invasive mechanism. Altogether this data infers that these factors may contribute to cell proliferation during initial phases of the tumor.

Interleukin-6 stimulates tubular regeneration in rats with glycerol-induced acute renal failure.

UNLABELLED: Interleukin-6 stimulates tubular regeneration in rats with glycerol-induced acute renal failure. BACKGROUND: Interleukin 6 (IL-6) is a pleiotropic cytokine released after endotoxemia, trauma and organ injury. IL-6 may act in cellular proliferation activating transduction signals and Ras/Map cascade or the HGF/c-met axis. We tested the effect of IL-6 in the regeneration of tubular epithelia after acute tubular necrosis (ATN) in rats. METHODS: Rats with glycerol-induced acute renal failure (Gly-ARF) were treated with IL-6 200 microg/kg/day. Functional, histological and immunohistochemical tests were done 24 and 72 h after Gly-ARF to localise mitotic cells (BrdU). The renal expression of c-met (Western-Blot) and circulating levels of HGF (ELISA) were also determined. RESULTS: Rats with Gly-ARF had reduced creatinine clearance that was not influenced by IL-6. The histological appearance of ATN was also unaffected by IL-6. The IL-6 treated rats showed a significant increase in tubular cell proliferation in cortex and medulla, as well as in the expression of c-met protein in the renal cortex, compared to untreated Gly-ARF rats. The plasma HGF concentration was equally elevated in treated and untreated Gly-ARF rats. DISCUSSION: IL-6 stimulates tubular regeneration after Gly-ARF and increases the expression of c-met in the renal cortex. Gly-ARF rats have high circulating levels of HGF that is targeted to act in the injured kidneys by the IL-6 overexpressed renal c-met.