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Objectives

Renal cell carcinoma (RCC) is characterized by a propensity for extension into the renal vein and inferior vena cava (IVC) and is associated with poor prognosis. BAP1 mutation, which occurs in about 15% of patients with clear cell RCC (ccRCC), also predicts poor prognosis. The aim of this study was to elucidate the association between BAP1 protein expression and clinicopathological outcomes in patients with nonmetastatic ccRCC with an IVC tumor thrombus (IVCTT).

Material and methods

Thirty-five patients with nonmetastatic ccRCC with an IVCTT who underwent radical nephrectomy and tumor thrombectomy at our institution from 1999 to 2010 were retrospectively evaluated. Immunohistochemical (IHC) analyses were performed for the expression of BAP1 protein, and the associations between the expression of BAP1 and clinical outcomes were assessed. Survival analyses were performed using the Kaplan-Meier method and log-rank test. Multivariate analyses of the associations between disease-free survival (DFS) and clinical variables including BAP1 protein expression, tumor size, Karnofsky performance status (KPS) score, and the extension level of the tumor thrombus were performed using a Cox proportional hazard model.

Results

The median follow-up time was 58.8 months (range: 2–130 months). The median age was 68 years (range: 37–80 years). The median size of the primary tumor was 9.6 cm (range: 3.0–15.0 cm). The IVCTT extended above and below the diaphragm in 10 (28.6%) and 25 (71.4%) patients, respectively. The KPS score was>80 in 23 patients (65.7%). BAP1 protein expression on IHC was positive in 24 cases (68.8%) and negative in 11 cases (31.2%). The median overall survival in cases with BAP1-negative and -positive tumor on IHC staining were 44.7 and 81.5 months, respectively (P = 0.052). BAP1-negative tumor on IHC staining was associated with a significantly shorter DFS than BAP1-positive tumor (median DFS = 10.0 vs. 26.0 months, respectively; P = 0.011). Multivariate analysis showed that only BAP1-negative tumor on IHC staining was significantly associated with shorter DFS (P = 0.004).

Conclusions

Patients whose tumors had loss of BAP1 protein expression were significantly associated with poor prognosis in patients with ccRCC with an IVCTT who underwent radical nephrectomy and tumor thrombectomy.  相似文献   
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According to TCGA database, mutations in PPP6C (encoding phosphatase PP6) are found in c. 10% of tumors from melanoma patients, in which they coexist with BRAF and NRAS mutations. To assess PP6 function in melanoma carcinogenesis, we generated mice in which we could specifically induce BRAF(V600E) expression and delete Ppp6c in melanocytes. In these mice, melanoma susceptibility following UVB irradiation exhibited the following pattern: Ppp6c semi-deficient (heterozygous) > Ppp6c wild-type > Ppp6c-deficient (homozygous) tumor types. Next-generation sequencing of Ppp6c heterozygous and wild-type melanoma tumors revealed that all harbored Trp53 mutations. However, Ppp6c heterozygous tumors showed a higher Signature 1 (mitotic/mitotic clock) mutation index compared with Ppp6c wild-type tumors, suggesting increased cell division. Analysis of cell lines derived from either Ppp6c heterozygous or wild-type melanoma tissues showed that both formed tumors in nude mice, but Ppp6c heterozygous tumors grew faster compared with those from the wild-type line. Ppp6c knockdown via siRNA in the Ppp6c heterozygous line promoted the accumulation of genomic damage and enhanced apoptosis relative to siRNA controls. We conclude that in the presence of BRAF(V600E) expression and UV-induced Trp53 mutation, Ppp6c haploinsufficiency promotes tumorigenesis.  相似文献   
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To retrospectively investigate the effects of indigo carmine intravenous injection on oxygen reserve index (ORi?) in 20 patients who underwent elective gynecologic surgery under general anesthesia. The study subjects were patients who underwent elective gynecologic surgery under general anesthesia between April 2016 and January 2017, and were administered a 5-ml intravenous injection of 0.4% indigo carmine for clinical purposes during surgery with ORi monitoring. Changes in ORi within 20 min after indigo carmine injection were observed. A relevant decrease in ORi was defined as ≥?10% reduction in ORi from pre-injection level. ORi rapidly decreased after indigo carmine intravenous injection in all patients. In 10 of 19 patients, ORi decreased to 0 after indigo carmine injection. The median lowest value of ORi was 0 (range 0–0.16) and the median time to reach the lowest value of ORi was 2 min (range 1–4 min) after injection. ORi values returned to pre-injection levels within 20 min in 13 of 19 patients, and the median time to return to pre-injection levels was 10 min (range 6–16 min) after injection. During ORi monitoring it is necessary to consider the rapid reduction in ORi after intravenous injection of indigo carmine.  相似文献   
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