DNA modifications such as 5-methylcytosine (5mC) and 5-hydroxymethylcytosine (5hmC) are epigenetic marks known to affect global gene expression in mammals. Given their prevalence in the human genome, close correlation with gene expression and high chemical stability, these DNA epigenetic marks could serve as ideal biomarkers for cancer diagnosis. Taking advantage of a highly sensitive and selective chemical labeling technology, we report here the genome-wide profiling of 5hmC in circulating cell-free DNA (cfDNA) and in genomic DNA (gDNA) of paired tumor and adjacent tissues collected from a cohort of 260 patients recently diagnosed with colorectal, gastric, pancreatic, liver or thyroid cancer and normal tissues from 90 healthy individuals. 5hmC was mainly distributed in transcriptionally active regions coincident with open chromatin and permissive histone modifications. Robust cancer-associated 5hmC signatures were identified in cfDNA that were characteristic for specific cancer types. 5hmC-based biomarkers of circulating cfDNA were highly predictive of colorectal and gastric cancers and were superior to conventional biomarkers and comparable to 5hmC biomarkers from tissue biopsies. Thus, this new strategy could lead to the development of effective, minimally invasive methods for diagnosis and prognosis of cancer from the analyses of blood samples.

Our analysis of the largest SM cohort in scale from a single institution offers a comprehensive view of the clinical characteristics of surgically treated SM, revealing the distinct biology of SM in comparison to its cranial counterparts, and providing guidance to improve surgical management of SM.

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Malignant gliomas are the most common and devastating primary brain tumors in adults. The rapid invasion of tumor cells into the adjacent normal brain tissues is a major cause of treatment failure, yet the mechanisms that regulate this process remain poorly understood. MicroRNAs have recently emerged as regulators of invasion and metastasis by acting on multiple signaling pathways. In this study, we found that miR-622 is significantly downregulated in glioma tissues and cell lines. Functional experiments showed that increased miR-622 expression reduced glioma cell invasion and migration, whereas decreased miR-622 expression enhanced cell invasion and migration. Moreover, activating transcription factor 2 (ATF2), an important transcription factor that regulate tumor invasion, was identified as a direct target of miR-622. Knockdown of ATF2 using small interefering RNA recapitulated the anti-invasive function of miR-622, whereas restoring the ATF2 expression attenuated the function of miR-622 in glioma cells. Furthermore, clinical data indicated that miR-622 and ATF2 were inversely expressed in glioma specimens. Our findings provide insight into the specific biological behavior of miR-622 in tumor invasion and migration. Targeting miR-622/ATF2 axis is a novel therapeutic approach for blocking glioma invasion.

BackgroundRecent studies have shown that disruption of circadian rhythms is one of the tumor promoting factors which contribute to mammalian cancer development and progression, but very little is known about the molecular changes of circadian genes in colorectal carcinoma (CRC). Thus, in this study, changes in the expression of human Period2 (hPer2), one of the key circadian clock regulators, in CRC and its correlation with prognosis were investigated.MethodsImmunohistochemical (IHC) staining and real-time PCR for hPer2 were performed for 38 CRC cases.ResultsIHC analysis detected positive staining for hPer2 in 81.6% (31/38) of CRC tissues and 97.4% (37/38) of surrounding non-cancerous tissues (P < 0.05). Most colorectal cells in non-cancerous tissues were homogeneously stained. In contrast, in the paired cancerous tissues, a heterogeneous pattern was found with a significant portion of cancer cells displaying negative or weak hPer2 staining. In over 60% cases (24/38), the staining for hPer2 was much stronger in non-cancerous cells than in the paired cancerous cells. Well-differentiated cancer cells are more likely to maintain hPer2 expression than poorly-differentiated ones. Furthermore, associations of decreased hPer2 levels with patients' age, histological grade, TNM stage and expression of nucleus proliferation related antigen: Ki67 were also detected (P < 0.05). Expression of hPer2 did not correlate with that of either p53 or C-erB-2. Similar to hPer2 protein expression, quantitative RT-PCR for hPer2 also showed decreased mRNA expression in CRC.ConclusionThese results suggest a role for hPer2 in normal colorectal cell function and the potential deregulation of hPer2 expression in the development, invasion, and metastasis of CRC.

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The effect of adjuvant radiotherapy in management for high‐grade meningiomas, especially atypical meningiomas, remains controversial. We aimed to explore the role of adjuvant radiotherapy in this population. A total of 162 adults with high‐grade meningiomas (99 atypical meningiomas and 63 anaplastic meningiomas) were treated from 2003 to 2008 at Huashan Hospital. One hundred and seventeen patients presented with primary and 45 with recurrent disease. One hundred and fifteen patients (70.9%) were treated with adjuvant radiotherapy after surgical resection. The median follow‐up was 76.5 months (range 1‐142 months). Kaplan‐Meier survival curve and Cox proportional hazards modeling were used for analyses. Adjuvant radiotherapy was associated with prolonged progression‐free survival (PFS) and overall survival (OS) in patients with newly diagnosed anaplastic meningiomas irrespective of extent of resection (PFS, P = .001; OS, P = .003). Gross total resection was the only independent prognostic factor for those with newly diagnosed atypical meningiomas (PFS, P < .001; OS, P = .012). A survival benefit for adjuvant radiation was also found in subgroup analysis of patients with high‐grade meningiomas who underwent subtotal resection (PFS, P = .023; OS, P = .013). Among recurrent high‐grade meningiomas, radiotherapy offered no statistically significant improvement in either PFS or OS. Adjuvant radiotherapy is associated with improved survival in patients with newly diagnosed anaplastic meningiomas and those high‐grade meningiomas following subtotal resection. However, there was no significant correlation identified between postoperative radiation and outcome for recurrent high‐grade meningiomas. Future prospective randomized trials may help clarify the optimal tailored treatment for patients with high‐grade meningioma.

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