a report from the Children's Oncology Group and the Utah Population Database

Relatively little is known about the epidemiology and factors underlying susceptibility to childhood rhabdomyosarcoma (RMS). To better characterize genetic susceptibility to childhood RMS, we evaluated the role of family history of cancer using data from the largest case–control study of RMS and the Utah Population Database (UPDB). RMS cases (n = 322) were obtained from the Children's Oncology Group (COG). Population-based controls (n = 322) were pair-matched to cases on race, sex, and age. Conditional logistic regression was used to evaluate the association between family history of cancer and childhood RMS. The results were validated using the UPDB, from which 130 RMS cases were identified and matched to controls (n = 1300) on sex and year of birth. The results were combined to generate summary odds ratios (ORs) and 95% confidence intervals (CI). Having a first-degree relative with a cancer history was more common in RMS cases than controls (ORs = 1.39, 95% CI: 0.97–1.98). Notably, this association was stronger among those with embryonal RMS (ORs = 2.44, 95% CI: 1.54–3.86). Moreover, having a first-degree relative who was younger at diagnosis of cancer (<30 years) was associated with a greater risk of RMS (ORs = 2.37, 95% CI: 1.34–4.18). In the largest analysis of its kind, we found that most children diagnosed with RMS did not have a family history of cancer. However, our results indicate an increased risk of RMS (particularly embryonal RMS) in children who have a first-degree relative with cancer, and among those whose relatives were diagnosed with cancer at <30 years of age

Refinement of risk stratification for childhood rhabdomyosarcoma using FOXO1 fusion status in addition to established clinical outcome predictors: A report from the Children's Oncology Group

Background: Previous studies of the prognostic importance of FOXO1 fusion status in patients with rhabdomyosarcoma (RMS) have had conflicting results. We re�examined risk stratification by adding FOXO1 status to traditional clinical prognostic factors in children with localized or metastatic RMS. Methods: Data from six COG clinical trials (D9602, D9802, D9803, ARST0331, ARTS0431, ARST0531; two studies each for low�, intermediate� and high�risk patients) accruing previously untreated patients with RMS from 1997 to 2013 yielded 1727 evaluable patients. Survival tree regression for event�free survival (EFS) was conducted to recursively select prognostic factors for branching and split. Factors included were age, FOXO1, clinical group, histology, nodal status, number of metastatic sites, primary site, sex, tumor size, and presence of metastases in bone/bone marrow, soft tissue, effusions, lung, distant lymph nodes, and other sites. Definition and outcome of the proposed risk groups were compared to existing systems and cross�validated results. Results: The 5�year EFS and overall survival (OS) for evaluable patients were 69% and 79%, respectively. Extent of disease (localized versus metastatic) was the first split (EFS 73% vs 30%; OS 84% vs. 42%). FOXO1 status (positive vs negative) was significant in the second split both for localized (EFS 52% vs 78%; OS 65% vs 88%) and metastatic disease (EFS 6% vs 46%; OS 19% vs 58%). Conclusions: After metastatic status, FOXO1 status is the most important prognostic factor in patients with RMS and improves risk stratification of patients with localized RMS. Our findings support incorporation of FOXO1 status in risk stratified clinical trials

MODEL PENGELOLAAN PASCA TANGKAP SEBAGAI UPAYA PENGENTASAN KEMISKINAN MASYARAKAT KAMPUNG NELAYAN DI PULAU ENGGANO

Relatively little is known about the epidemiology and factors underlying susceptibility to childhood rhabdomyosarcoma (RMS). To better characterize genetic susceptibility to childhood RMS, we evaluated the role of family history of cancer using data from the largest case-control study of RMS and the Utah Population Database (UPDB). RMS cases (n=322) were obtained from the Children's Oncology Group (COG). Population-based controls (n=322) were pair-matched to cases on race, sex, and age. Conditional logistic regression was used to evaluate the association between family history of cancer and childhood RMS. The results were validated using the UPDB, from which 130 RMS cases were identified and matched to controls (n=1300) on sex and year of birth. The results were combined to generate summary odds ratios (ORs) and 95% confidence intervals (CI). Having a first-degree relative with a cancer history was more common in RMS cases than controls (ORs=1.39, 95% CI: 0.97-1.98). Notably, this association was stronger among those with embryonal RMS (ORs=2.44, 95% CI: 1.54-3.86). Moreover, having a first-degree relative who was younger at diagnosis of cancer (&lt;30years) was associated with a greater risk of RMS (ORs=2.37, 95% CI: 1.34-4.18). In the largest analysis of its kind, we found that most children diagnosed with RMS did not have a family history of cancer. However, our results indicate an increased risk of RMS (particularly embryonal RMS) in children who have a first-degree relative with cancer, and among those whose relatives were diagnosed with cancer at &lt;30years of age

Arf induction by Tgfβ is influenced by Sp1 and C/ebpβ in opposing directions.

Recent studies show that Arf, a bona fide tumor suppressor, also plays an essential role during mouse eye development. Tgfβ is required for Arf promoter activation in developing mouse eyes, and its capacity to induce Arf depends on Smads 2/3 as well as p38 Mapk. Substantial delay between activation of these pathways and increased Arf transcription imply that changes in the binding of additional transcription factors help orchestrate changes in Arf expression. Focusing on proteins with putative DNA binding elements near the mouse Arf transcription start, we now show that Tgfβ induction of this gene correlated with decreased expression and DNA binding of C/ebpβ to the proximal Arf promoter. Ectopic expression of C/ebpβ in mouse embryo fibroblasts (MEFs) blocked Arf induction by Tgfβ. Although basal levels of Arf mRNA were increased by C/ebpβ loss in MEFs and in the developing eye, Tgfβ was still able to increase Arf, indicating that derepression was not the sole factor. Chromatin immunoprecipitation (ChIP) assay showed increased Sp1 binding to the Arf promotor at 24 and 48 hours after Tgfβ treatment, at which time points Arf expression was significantly induced by Tgfβ. Chemical inhibition of Sp1 and its knockdown by RNA interference blocked Arf induction by Tgfβ in MEFs. In summary, our results indicate that C/ebpβ and Sp1 are negative and positive Arf regulators that are influenced by Tgfβ

Temporally distinct roles for tumor suppressor pathways in cell cycle arrest and cellular senescence in Cyclin D1-driven tumor

Abstract Background Cellular senescence represents a tumor suppressive response to a variety of aberrant and oncogenic insults. We have previously described a transgenic mouse model of Cyclin D1-driven senescence in pineal cells that opposes tumor progression. We now attempted to define the molecular mechanisms leading to p53 activation in this model, and to identify effectors of Cyclin D1-induced senescence. Results Senescence evolved over a period of weeks, with initial hyperproliferation followed by cell cycle arrest due to ROS production leading to activation of a DNA damage response and the p53 pathway. Interestingly, cell cycle exit was associated with repression of the Cyclin-dependent kinase Cdk2. This was followed days later by formation of heterochromatin foci correlating with RB protein hypophosphorylation. In the absence of the Cdk4-inhibitor p18Ink4c, cell cycle exit was delayed but most cells eventually showed a senescent phenotype. However, tumors later arose from this premalignant, largely senescent lesion. We found that the p53 pathway was intact in tumors arising in a p18Ink4c-/- background, indicating that the two genes represent distinct tumor suppressor pathways. Upon tumor progression, both p18Ink4c-/- and p53-/- tumors showed increased Cdk2 expression. Inhibition of Cdk2 in cultured pre-tumorigenic and tumor cells of both backgrounds resulted in decreased proliferation and evidence of senescence. Conclusion Our findings indicate that the p53 and the RB pathways play temporally distinct roles in senescence induction in Cyclin D1-expressing cells, and that Cdk2 inhibition plays a role in tumor suppression, and may be a useful therapeutic target.</p

Inverse correlation of C/ebpβ and <i>Arf</i> expression during Tgfβ treatment.

<p>(A). Schematic diagram showing potential C/ebpβ, Smad, Sp1 and E2F binding sites at the <i>Arf</i> promoter. (B). Tgfβ decreases C/ebpβ binding to the <i>Arf</i> locus in MEFs. Quantitative analysis of representative chromatin immunoprecipitation (ChIP) assays of using wild type MEFs exposed to vehicle (V) or Tgfβ (T) for 1.5 hours or 24 hours. ChIP assay was carried out using antibodies specific to C/ebpβ and IgG. Immunoprecipitated DNA and input DNA were amplified with primers for proximal regions genomic <i>Arf</i> promoter. <i>p</i>-values as follows: 0.1 (<a href="mailto:@" target="_blank">@</a>) and 0.2 (%) for Tgfβ versus corresponding vehicle. (C). Quantitative analysis of real time, RT-PCR using total RNA isolated from WT MEFs shows the expression of C/ebpβ mRNA changes during Tgfβ treatment up to 72 hours. The data is plotted as the fold changes of target genes from cells treated with Tgfβ (T) (5 ng/ml) versus the same cells treated with vehicle (V) (4 mM HCl). The significant changes between Tgfβ treatment and vehicle treatment was marked as * (p<0.05). (D) Representative western blot of lysates from wild type MEFs treated with Tgfβ (T) and vehicle (V) at different time points showing the inverse correlation of C/ebpβ and <i>Arf</i> protein expression.</p

The effects of overexpression or absence of C/ebpβ on <i>Arf</i> induction by Tgfβ.

<p>(A). β-galactosidase activity in <i>Arf ^lacZ/lacZ</i> MEFs showing the effects of ectopically-expressed C/ebpβ (LAP form) on <i>Arf</i> induction following 48 hour exposure to Tgfβ. Significant increase (*) and decrease (#) of Arf^lacZ expression is represented in the figure. *, #, p<0.05. (B) Representative western blot for the indicated proteins using lysates from wild type MEFs, exposed to 48 hours of Tgfβ (T) and vehicle (V) after transduction using Gfp- or C/ebpβ (LAP form)-expressing retrovirus. (C) qRT-PCR using total RNA isolated from <i>C/ebpβ ^+/+</i> and <i>C/ebpβ ^−/−</i> MEFs exposed to vehicle (V) or Tgfβ (T) for 48 hours. Differences in transcript level between Tgfβ- and vehicle-treated <i>C/ebpβ ^+/+</i> MEFs are significant [p<0.05 (*)]. Differences in transcript level between vehicle-treated <i>C/ebpβ ^+/+</i> and <i>C/ebpβ ^−/−</i> MEFs are significant, too [p<0.05 (**)]. (D) Representative western blot for the indicated proteins using lysates from <i>C/ebpβ ^+/+</i> and <i>C/ebpβ ^−/−</i> MEFs exposed to vehicle (V) or Tgfβ (T) for 48 hours.</p

Loss of C/ebpβ increases <i>Arf</i> mRNA expression in vitreous of developing eye.

<p>(A). qRT-PCR analysis using total RNA isolated from the vitreous (V), lens (L) and retina (R) from E13.5 WT mouse embryos. Expression was normalized to that of <i>Gapdh</i>. (B) qRT-PCR analysis using total RNA isolated from the vitreous from E13.5 <i>C/ebpβ ^+/+</i> and <i>C/ebpβ ^−/−</i> mouse embryos. Expression was normalized to that of <i>Gapdh</i>. (C) <i>Arf</i> expression is limited to previously identified sites in <i>C/ebpβ ^−/−</i> mice during development. (a, b) Representative photomicrographs of hematoxylin- and eosin-stained and X-Gal stained slides of P1 mouse eye of the indicated genotype. Note that <i>Arf</i>-expressing cells are limited to the vitreous (blue staining) in the <i>Arf ^lacZ/lacZ, C/ebpβ ^−/−</i> embryo, similar to the littermate <i>Arf ^lacZ/lacZ, C/ebpβ ^+/+</i> control embryo. (c,d) Representative whole-mount, E13.5 embryo from mice of the indicated genotype, following X-gal staining. Note that <i>Arf</i>-expressing cells are limited to the umbilical artery (arrow) in the <i>Arf ^lacZ/lacZ, C/ebpβ ^−/−</i> embryo, similar to its littermate <i>Arf ^lacZ/lacZ, C/ebpβ ^+/+</i> control embryo. K, kidney; B, bladder. (D). Representative photomicrographs of hematoxylin- and eosin-stained slides of E15.5 embryos showing there is no primary vitreous hyperplasia in <i>C/ebpβ ^−/−</i> embryos. Arrows denote the cellular area of the primary vitreous.</p