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991.
This study reports an autopsy case of a 53 year-old male with rapidly progressive extra-nodal NK/T-cell lymphoma accompanied with unusual clinical and pathologic features. He was initially presented with localized swelling and tenderness in the right lower extremity and the biopsy from the calf muscle was interpreted as granulomatous myositis masquerizing lymphoma. The biopsy from erythematous skin lesion of trunk showed infiltration of medium sized atypical lymphoid cells with relatively plump cytoplasm and immunophenotype of CD30+, CD56+/- and surface CD3-, which lead to the diagnosis of CD30+ anaplastic large cell lymphoma. About 2 months later, nasal obstruction was developed and the nasal biopsy was done. After confirmation of EBV infection, he was finally diagnosed as extra-nodal NK/T-cell lymphoma with peculiar immunophenotype of CD3 dim+ and CD30+. Despite the chemotherapy, he was going rapidly downhill and died of respiratory and multi-organ failure 8 months after the onset of soft tissue lesion. At autopsy, disseminated angiocentric lymphoma was found all over the internal organs including the brain. This case emphasizes that extra-nodal NK/T-cell lymphoma should be considered as a cause of granulomatous myositis and can express CD30 positivity and CD3 weak positivity, which are unusual but rarely predominant feature of NK/T-cell lymphoma.  相似文献   
992.
The chemotherapeutic agent temozolomide (TMZ) and the anti-angiogenic agent thalidomide (THD) have both demonstrated anti-tumor activity in patients with recurrent malignant glioma. Combination treatment with TMZ and THD in patients with glioblastoma multiforme (GBM) appears to be more effective than treatment with either drug alone. To investigate the mechanism of this anti-tumor effect, we examined the combined effects of TMZ and THD in a rat glioma xenograft model. We found that combination treatment markedly inhibited the growth of tumors that were orthotopically implanted into rat brains. Using proliferating cell nuclear antigen (PCNA) staining, we observed a significant decrease in cell proliferation in these tumors. CD31 staining of the microvasculature revealed a significant decrease in angiogenesis. We also found increased apoptosis in treated tumors by terminal deoxynucleotidyl-mediated deoxyuridine triphosphate nick-end labeling (TUNEL) assay. We further demonstrated that the expression of angiogenic factors, such as vascular endothelial cell growth factor (VEGF) and basic fibroblastic growth factor (bFGF), were inhibited by THD. THD also decreased the number of ED1-positive, activated macrophages or microglial cells, which produce pro-angiogenic molecules around the glioma. Taken together, these results suggest that combination treatment with TMZ and THD inhibits tumor growth via the induction of apoptosis and the inhibition of angiogenesis in a rat model and may be a promising therapy for malignant gliomas.  相似文献   
993.

Background

The purpose of the study was to compare cancer detection rates between 12-core transrectal ultrasound-guided prostate biopsy (TRUS-Bx) and multiparametric magnetic resonance imaging (mpMRI)-guided target prostate biopsy (MRI-TBx) according to prostate-specific antigen (PSA) level in biopsy-naive patients.

Patients and Methods

A retrospective study was conducted in 2009 biopsy-naive patients with suspected prostate cancer (PSA ≤20 ng/mL). Patients underwent TRUS-Bx (n = 1786) or MRI-guided target prostate biopsy (MRI-TBx; n = 223) from September 2013 to March 2017 and were stratified according to each of 4 PSA cutoffs. MRI-TBx was performed on lesions with Prostate Imaging Reporting and Data System (PI-RADS) scores of 3 to 5 on mpMRI. Clinically significant prostate cancer (csPCa) was defined as Gleason ≥7. Propensity score matching was performed using the prebiopsy variables, which included age, PSA, prostate volume, and PSA density.

Results

Propensity score matching resulted in 222 patients in each group. There were significant differences between the TRUS-Bx and MRI-TBx groups in the overall detection rates of prostate cancer (41.4% vs. 55.4%; P = .003) and csPCa (30.1% vs. 42.8%; P = .005). However, across PSA cutoffs, MRI-TBx detected more prostate cancer than TRUS-Bx at PSA levels of 2.5 to <4 (29.5% vs. 56.6%; P < .001). The csPCa detection rates of TRUS-Bx and MRI-TBx did not differ significantly within the PSA cutoffs. There was a significantly higher detection rate of prostate cancer and csPCa in lesions with PI-RADS scores 4 and 5 than in those with a score of 3.

Conclusion

Prebiopsy mpMRI and subsequent targeted biopsy had a higher detection rate than TRUS-Bx in patients with prostate cancer and csPCa.  相似文献   
994.
Both hypermethylation of the tumor suppressor gene RASSF1A and activating mutations of the KRAS and/or BRAF gene have been reported in a variety of human cancers. To investigate these epigenetic and genetic alterations in endometrial carcinoma (EC), we examined their frequency in 4 uterine EC cell lines and in 75 sporadic primary ECs. Using methylation specific PCR, we found RASSF1A methylation in 25 of 75 (33.3%) ECs. RASSF1A methylation was significantly associated with microsatellite instability (MSI, p < 0.001) and also with hMLH1 methylation (p < 0.001). KRAS mutations were detected in 14 of 75 (18.7%) ECs. BRAF mutations were identified in only 3 of 75 (4.0%) ECs and were not found in ECs with KRAS mutations or RASSF1A methylation. RASSF1A methylation was more frequent in KRAS mutation-negative ECs than in KRAS mutation-positive ECs (37.7% vs 14.3%), but this inverse correlation is not statistically significant (p = 0.122). However, we observed that RASSF1A methylation was inversely correlated with KRAS and/or BRAF mutations (p = 0.028) in MSI-negative ECs, while this inverse correlation disappeared in MSI-positive ECs. Furthermore, in MSI-positive ECs, 2 cases of concomitant RASSF1A methylation and KRAS mutation were found. Taken together, these results provide strong evidence that, in EC tumorigenesis, RASSF1A promoter hypermethylation is as important as KRAS mutations in activating the RAS pathway.  相似文献   
995.
Endostatin is the C-terminal antiangiogenic fragment of the extracellular matrix protein collagen XVIII, and is generated by tumor-derived proteases. The presence of serum endostatin in patients with gastric cancer has not been reported. The authors assessed the serum levels of endostatin in patients with gastric carcinoma and evaluated their association with the levels of vascular endothelial growth factor (VEGF) and the clinical outcome. A total of 107 patients with gastric cancer were included in the study. Pretherapeutic serum levels of endostatin and VEGF were measured using an ELISA, and compared with those in 23 healthy controls. The serum levels of endostatin and VEGF were higher in gastric cancer patients than in healthy controls (endostatin, 70.1 +/- 16.6 vs. 52.2 +/- 6.2 ng/mL [p < 0.001]; VEGF, 55.1 +/- 7.6 vs. 32.1 +/- 2.4 ng/mL [p < 0.001]; mean +/- SD). Serum endostatin levels were significantly associated with the presence of distant metastases (r = 0.556, p < 0.001) and VEGF levels (r = 0.335, p < 0.001), but not with the depth of tumor invasion, differentiation, or regional lymph node status. A serum endostatin level above the 75th percentile of the distribution for the patients (79.2 ng/mL) was associated with a poor outcome (last follow-up at 42 months; median survival time, 9 vs. 20 months [log-rank, p = 0.017]; median time to progression, 5 vs. 10 months [log-rank, p = 0.022]) in the patients with metastatic gastric cancer. The results suggest for the first time that an elevated serum level of endostatin at the diagnosis of metastatic gastric cancer could be predictive of a poor outcome.  相似文献   
996.
A new anthracycline ID6105 (11-hydroxyaclacinomycin X, Hyrubicin), which has potent antitumor activities against a broad range of cancer cell lines, was produced by hybrid biosynthetic approach. We investigated ID6105-induced apoptosis and in vivo efficacy on experimental tumors, and also defined its optimal dosing schedule. From PARP cleavage assay and caspase-3 activation assay, we found that ID6105 can induce apoptosis in tumor cells and its ability was superior to doxorubicin. In human tumor xenograft models, ID6105 showed greater antitumor effects on SW620 and NCI-H23 than doxorubicin. The 1 mg/kg of ID6105 treatment reduced size of tumor by 93% in NCI-H23 model whereas doxorubicin (2 mg/kg) showed only 39% inhibition rate. In SW620 model, 0.3 mg/kg of ID6105 proved to be comparable to 2 mg/kg of doxorubicin. Testing with several dosing schedule such as qd10, qd5, and q4d3, we decided intravenous qd5 treatment was an optimal schedule as a dose regimen of ID6105. In conclusion, ID6105 is a potent apoptosis-inducing anthracycline and effective in treatment of tumors with qd5 dosing schedule.  相似文献   
997.
998.
Growing evidence suggests that obesity, an established cause of renal cell cancer (RCC), may also be associated with a better prognosis. To evaluate the association between RCC survival and obesity, we analyzed a large cohort of patients with RCC and undertook a meta‐analysis of the published evidence. We collected clinical and pathologic data from 1,543 patients who underwent nephrectomy for RCC between 1994 and 2008 with complete follow‐up through 2008. Patients were grouped according to BMI (kg/m2): underweight <18.5, normal weight 18.5 to <23, overweight 23 to <25 and obese ≥25. We estimated survival using the Kaplan–Meier method and Cox proportional hazard models to examine the impact of BMI on overall survival (OS) and cancer‐specific survival (CSS) with adjustment for covariates. We performed a meta‐analysis of BMI and OS, CSS and recurrence‐free survival (RFS) from all relevant studies using a random‐effects model. The 5‐year CSS increased from 76.1% in the lowest to 92.7% in the highest BMI category. A multivariate analysis showed higher OS [hazard ratio (HR) = 0.45; 95% CI: 0.29–0.68) and CSS (HR = 0.47; 95% CI: 0.29–0.77] in obese patients than in normal weight patients. The meta‐analysis further corroborated that high BMI significantly improved OS (HR = 0.57; 95% CI: 0.43–0.76), CSS (HR = 0.59; 95% CI: 0.48–0.74) and RFS (HR = 0.49; 95% CI: 0.30–0.81). Our study shows that preoperative BMI is an independent prognostic indicator for survival among patients with RCC.  相似文献   
999.
The aim of this study was to analyze the effect of the type of local surgical treatment on survival in young women aged less than 40 years with T1 breast cancer. We analyzed data from 3,512 patients aged ≤40 years old who were diagnosed with T1 breast cancer from the Korean Breast Cancer Registry database between January 1988 and December 2006 and underwent either breast-conserving therapy (BCT) or mastectomy. The overall survival (OS) and breast-cancer-specific survival (BCSS) were compared between BCT and mastectomy. Of the 3,512 patients analyzed, 1,951 (55.6 %) underwent BCT, and 1,561 (44.4 %) underwent mastectomy. The median follow-up period was 111.0 (79.0–131.5) months. Overall, the 10-year OS rates for BCT and mastectomy were 95 and 92.1 %, respectively (p = 00004), and the 10-year BCSS rates for BCT and mastectomy patients were 96.9 and 94.9 %, respectively (p = 0.12). In node-negative patients, no significant difference was observed in either the OS (adjusted hazard ratio [HR] 1.072; 95 % CI, 0.750–1.5332, p = 0.704) or BCSS (adjusted HR 0.988; 95 % CI, 0.620–1.574, p = 0.960) rate between the BCT and mastectomy groups. In node-positive patients, no significant difference was observed in the OS (adjusted HR 1.634; 95 % CI, 0.982–2.272, p = 0.59) and BCSS (adjusted HR 1.410; 95 % CI, 0.755–2.633, p = 0.281) rates between the BCT and mastectomy groups. In this large, population-based analysis of young women with T1 breast cancer, the OS and BCSS were not different between BCT and mastectomy.  相似文献   
1000.
Promoter hypermethylation of the ADAM23 gene, which is normally involved in cell‐to‐cell and cell‐to matrix adhesion, has been reported in pancreatic, breast and brain cancer, and recently the role of this gene was examined in gastric cancer. In this study, we analyzed ADAM23 expression in colorectal cancer cell lines and examined its methylation by methylation‐specific PCR (MSP) and bisulfate‐modified DNA sequencing analysis. Methylated cells were treated with 5‐aza‐2′‐deoxycytidine to restore the ADAM23 expression. We then examined ADAM23 methylation status in colorectal cancer tissues and their corresponding normal tissues. We found that ADAM23 was aberrantly silenced or expressed at very low levels in 28 of the 32 (88%) colorectal cancer cell lines. MSP analysis showed that ADAM23 was methylated in 29 of 32 (91%) colorectal cancer cell lines and attenuated expression of ADAM23 was found to be related to hypermethylation in its promoter region. Moreover, the CpG dinucleotide methylation threshold of 70–90% was found to be required for complete silencing. In addition, when some cell lines without ADAM23 expression were treated with 5‐aza‐2′‐deoxycytidine, ADAM23 was reexpressed. In colorectal cancer tissues, the promoter region of ADAM23 was hypermethylated in 36 of 76 (47%). These results demonstrated that ADAM23 may be down‐regulated by aberrant promoter hypermethylation during the progression of colorectal cancer. © 2008 Wiley‐Liss, Inc.  相似文献   
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