The transcription factor hypoxia-inducible factor-1␣ (HIF-1␣) plays pivotal roles in physiology and pathophysiology. Constitutive or hypoxia-induced HIF-1␣ overexpression is observed in many types of cancers including prostate adenocarcinoma, in which it is associated with resistance to apoptosis and therapeutic agents. BCL-xL, a hypoxia-responsive, anti-apoptotic protein of the Bcl-2 family, is also overexpressed in prostate carcinoma and many other cancers. Despite this connection, whether BCL-xL expression is directly regulated by HIF-1␣ is not known. We used prostate cancer PC-3 cell with constitutive high HIF-1␣ level as a model to address this important question. We first generated prostate cancer PC-3 cells in which HIF-1␣ was stably knocked-down (HIF-KD) by using small interference RNA. BCL-xL was dramatically decreased in HIF-KD PC-3 cells, in parallel with sensitization to apoptosis with caspase-3 activation as well as decreased cell proliferation. We then demonstrated that HIF-1␣ directly regulated BCL-xL transcription by binding to a hypoxia-responsive element in the BCL-xL promoter (؊865 to ؊847) by reporter gene assay, chromatin immunoprecipitation, and electrophoretic mobility shift and supershift assays. HIF-1␣-dependent BCL-xL overexpression may be an important mechanism by which HIF-1␣ protects prostate cancer cells from apoptosis and leads to treatment resistance.
The putative tumor suppressor miR145 is transcriptionally regulated by TP53 and is downregulated in many tumors; however, its role in prostate cancer is unknown. On the other hand, BCL2/adenovirus E1B 19-kDa interacting protein 3 (BNIP3) is overexpressed in various tumors, including prostate cancer, and may transcriptionally repress the apoptosis-inducing factor (AIF) gene. Although BNIP3 transcription is controlled by hypoxia-inducible factor 1α (also elevated in prostate cancer), we postulated the posttranscriptional regulation of BNIP3 by miR145 through bioinformatics analysis, and herein we experimentally showed that miR145 negatively regulated BNIP3 by targeting its 3′-untranslated region. Artificial overexpression of miR145 by using adenoviral vectors in prostate cancer PC-3 and DU145 cells significantly downregulated BNIP3, together with the upregulation of AIF, reduced cell growth, and increased cell death. Artificial overexpression of wild-type TP53 in PC-3 cells (which lack TP53 protein) and DU145 cells (in which mutated nonfunctioning TP53 is expressed) significantly upregulated miR145 expression with consequent effects on BNIP3 and cell behavior as with miR145 overexpression. Analysis of prostate cancer (n = 134) and benign prostate (n = 83) tissue sample showed significantly decreased miR145 and increased BNIP3 expression in prostate cancer (P < 0.001), particularly in those with tumor progression, and both molecular changes were associated with unfavorable outcome. Abnormalities of the miR145-BNIP3 pair as part of TP53-miR145-BNIP3-AIF network may play a major role in prostate cancer pathogenesis and progression. Cancer Res; 70(7); 2728-38. ©2010 AACR.
TFE3-translocation renal cell carcinoma (TFE3-tRCC) is a rare and heterogeneous subtype of kidney cancer with no standard treatment for advanced disease. We describe comprehensive molecular characteristics of 63 untreated primary TFE3-tRCCs based on whole-exome and RNA sequencing. TFE3-tRCC is highly heterogeneous, both clinicopathologically and genotypically. ASPSCR1-TFE3 fusion and several somatic copy number alterations, including the loss of 22q, are associated with aggressive features and poor outcomes. Apart from tumors with MED15-TFE3 fusion, most TFE3-tRCCs exhibit low PD-L1 expression and low T-cell infiltration. Unsupervised transcriptomic analysis reveals five molecular clusters with distinct angiogenesis, stroma, proliferation and KRAS down signatures, which show association with fusion patterns and prognosis. In line with the aggressive nature, the high angiogenesis/stroma/proliferation cluster exclusively consists of tumors with ASPSCR1-TFE3 fusion. Here, we describe the genomic and transcriptomic features of TFE3-tRCC and provide insights into precision medicine for this disease.
The presence of IDC-P in initial diagnosed metastatic prostate cancer, even among patients with more aggressive pattern, was firstly found to be significantly and independently associated with earlier occurrence of CRPC and poorer OS. We recommended the presence of IDC-P should be a routine record in pathological report of clinical diagnosis and other potential therapeutic regimen might be added to intervene in the integrated therapy as early as possible. Prostate 75:225-232, 2015. © 2014 Wiley Periodicals, Inc.
Purpose: Fumarate hydratase–deficient renal cell carcinoma (FH-deficient RCC) is a rare but lethal subtype of RCC. Little is known about the genomic profile of FH-deficient RCC, and the therapeutic options for advanced disease are limited. To this end, we performed a comprehensive genomics study to characterize the genomic and epigenomic features of FH-deficient RCC. Experimental Design: Integrated genomic, epigenomic, and molecular analyses were performed on 25 untreated primary FH-deficient RCCs. Complete clinicopathologic and follow-up data of these patients were recorded. Results: We identified that FH-deficient RCC manifested low somatic mutation burden (median 0.58 mutations per megabase), but with frequent somatic copy-number alterations. The majority of FH-deficient RCCs were characterized by a CpG sites island methylator phenotype, displaying concerted hypermethylation at numerous CpG sites in genes of transcription factors, tumor suppressors, and tumor hallmark pathways. However, a few cases (20%) with low metastatic potential showed relatively low DNA methylation levels, indicating the heterogeneity of methylation pattern in FH-deficient RCC. Moreover, FH-deficient RCC is potentially highly immunogenic, characterized by increased tumor T-cell infiltration but high expression of immune checkpoint molecules in tumors. Clinical data further demonstrated that patients receiving immune checkpoint blockade–based treatment achieved improved progression-free survival over those treated with antiangiogenic monotherapy (median, 13.3 vs. 5.1 months; P = 0.03). Conclusions: These results reveal the genomic features and provide new insight into potential therapeutic strategies for FH-deficient RCC.
By detecting spontaneous low-frequency fluctuations (LFF) of blood oxygen level–dependent (BOLD) signals, resting-state functional magnetic resonance imaging (rfMRI) measurements are believed to reflect spontaneous cerebral neural activity. Previous fMRI studies were focused on the examination of motor-related areas and little is known about the functional changes in the extra-motor areas in amyotrophic lateral sclerosis (ALS) patients. The aim of this study is to investigate functional cerebral abnormalities in ALS patients on a whole brain scale. Twenty ALS patients and twenty age- and sex-matched healthy volunteers were enrolled. Voxel-based analysis was used to characterize the alteration of amplitude of low frequency fluctuation (ALFF). Compared with the controls, the ALS patients showed significantly decreased ALFF in the visual cortex, fusiform gyri and right postcentral gyrus; and significantly increased ALFF in the left medial frontal gyrus, and in right inferior frontal areas after grey matter (GM) correction. Taking GM volume as covariates, the ALFF results were approximately consistent with those without GM correction. In addition, ALFF value in left medial frontal gyrus was negatively correlated with the rate of disease progression and duration. Decreased functional activity observed in the present study indicates the underlying deficits of the sensory processing system in ALS. Increased functional activity points to a compensatory mechanism. Our findings suggest that ALS is a multisystem disease other than merely motor dysfunction and provide evidence that alterations of ALFF in the frontal areas may be a special marker of ALS.
In this study, vitamin C was administered at various times as a sour stimulant to thyroid cancer patients, and the effect on salivary absorbed dose of therapeutic radioiodine ( 131 I) was investigated. Methods: Patients with differentiated thyroid cancer who had been prepared for thyroid remnant ablation after total thyroidectomy were prospectively recruited and, using a randomnumber table, were divided into 4 groups. In the hypothyroid condition, the patients in groups A, B, C, and D began sucking vitamin C (100 mg every 4 h in the daytime over 6 d) at 1, 5, 13, and 25 h, respectively, after receiving 3.7 GBq of 131 I. Scintigraphic images of the head and neck were serially acquired after 131 I administration to assess biokinetics in the salivary glands. Calculation of salivary absorbed dose was based on the MIRD schema of the Society of Nuclear Medicine. Results: Seventytwo patients (18,18,19, and 17 patients from groups A, B, C, and D, respectively) were eligible for the analysis of salivary dosimetry. Differences in absorbed doses to the parotid salivary gland (0.18 6 0.11, 0.16 6 0.07, 0.16 6 0.09, and 0.16 6 0.12 mGy/MBq in groups A, B, C, and D, respectively; P 5 0.37) and submandibular salivary gland (0.19 6 0.05, 0.17 6 0.05, 0.18 6 0.07, and 0.17 6 0.06 mGy/MBq, respectively; P 5 0.28) were not statistically significant among groups. Salivary cumulated activities arising from the first 24 h after 131 I administration accounted for 86.08% 6 7.89% (range, 75%298%) of total cumulated activities. Differences in salivary absorbed dose during the first 24 h were not statistically significant among the 4 groups either (P 5 0.32 and 0.24, respectively, for the parotid and submandibular salivary glands). Conclusion: Salivary stimulation with vitamin C at any time after 131 I administration has only a limited effect on salivary absorbed dose in thyroid cancer patients.
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