Purpose We hypothesized that four criteria could help identify malignant mesotheliomas (MMs) most likely linked to germline mutations of BAP1 or of other genes: family history of MM, BAP1-associated cancers, or multiple malignancies; or age younger than 50 years. Patients and Methods Over the course of 7 years, 79 patients with MM met the four criteria; 22 of the 79 (28%) reported possible asbestos exposure. They were screened for germline BAP1 mutations by Sanger sequencing and by targeted next-generation sequencing (tNGS) for germline mutations in 55 additional cancer-linked genes. Deleterious mutations detected by tNGS were validated by Sanger sequencing. Results Of the 79 patients, 43 (16 probands and 27 relatives) had deleterious germline BAP1 mutations. The median age at diagnosis was 54 years and median survival was 5 years. Among the remaining 36 patients with no BAP1 mutation, median age at diagnosis was 45 years, median survival was 9 years, and 12 had deleterious mutations of additional genes linked to cancer. When compared with patients with MMs in the SEER cohort, median age at diagnosis (72 years), median survival for all MM stages (8 months), and stage I (11 months) were significantly different from the 79 patients with MM in the current study ( P < .0001). Conclusion We provide criteria that help identify a subset of patients with MM who had significantly improved survival. Most of these patients were not aware of asbestos exposure and carried either pathogenic germline mutations of BAP1 or of additional genes linked to cancer, some of which may have targeted-therapy options. These patients and their relatives are susceptible to development of additional cancers; therefore, genetic counseling and cancer screening should be considered.

Asbestos causes malignant transformation of primary human mesothelial cells (HM), leading to mesothelioma. The mechanisms of asbestos carcinogenesis remain enigmatic, as exposure to asbestos induces HM death. However, some asbestos-exposed HM escape cell death, accumulate DNA damage, and may become transformed. We previously demonstrated that, upon asbestos exposure, HM and reactive macrophages releases the high mobility group box 1 (HMGB1) protein that becomes detectable in the tissues near asbestos deposits where HMGB1 triggers chronic inflammation. HMGB1 is also detectable in the sera of asbestos-exposed individuals and mice. Searching for additional biomarkers, we found higher levels of the autophagy marker ATG5 in sera from asbestos-exposed individuals compared to unexposed controls. As we investigated the mechanisms underlying this finding, we discovered that the release of HMGB1 upon asbestos exposure promoted autophagy, allowing a higher fraction of HM to survive asbestos exposure. HMGB1 silencing inhibited autophagy and increased asbestos-induced HM death, thereby decreasing asbestos-induced HM transformation. We demonstrate that autophagy was induced by the cytoplasmic and extracellular fractions of HMGB1 via the engagement of the RAGE receptor and Beclin 1 pathway, while nuclear HMGB1 did not participate in this process. We validated our findings in a novel unique mesothelial conditional HMGB1-knockout (HMGB1-cKO) mouse model. Compared to HMGB1 wild-type mice, mesothelial cells from HMGB1-cKO mice showed significantly reduced autophagy and increased cell death. Autophagy inhibitors chloroquine and desmethylclomipramine increased cell death and reduced asbestos-driven foci formation. In summary, HMGB1 released upon asbestos exposure induces autophagy, promoting HM survival and malignant transformation.

We describe the electrochemical detection of DNA methylation through the direct oxidation of both 5-methylcytosine (mC) and cytosine (C) in 5'-CG-3' sequence (CpG) oligonucleotides using a sputtered nanocarbon film electrode after digesting a longer CpG oligonucleotide with endonuclease P1. Direct electrochemistry of the longer CpG oligonucleotides was insufficient for obtaining the oxidation currents of these bases because the CG rich sequence inhibited the direct oxidation of each base in the longer CpG oligonucleotides, owing to the conformational structure and its very low diffusion coefficient. To detect C methylation with better quantitativity and sensitivity in the relatively long CpG oligonucleotides, we successfully used an endonuclease P1 to digest the target CpG oligonucleotide and yield an identical mononucleotide 2'-deoxyribonucleoside 5'-monophosphate (5'-dNMP). Compared with results obtained without P1 treatment, we achieved 4.4 times higher sensitivity and a wider concentration range for mC detection with a resolution capable of detecting a subtle methylated cytosine difference in the CpG oligonucleotides (60mer).

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The transcribed-ultraconserved regions (T-UCRs) are a novel class of non-coding RNAs, which are absolutely conserved (100%) between the orthologous regions of the human, rat and mouse genomes. Previous studies have described that several T-UCRs show differential expressions in cancers and might be involved in cancer development. We investigated the transcriptional levels of representative 26 T-UCRs and determined the regions that were differently expressed in prostate cancer (PCa) and gastric cancer (GC). A quantitative reverse transcription-polymerase chain reaction analysis revealed the downregulation of Uc.158+A expression by a DNA methylation-associated mechanism, which was restored by 5-Aza-dC (5-aza-2'-deoxycytidine) treatment. Bisulfite genomic sequencing using cell lines and tissue samples demonstrated cancer-specific CpG hypermethylation in both GC and PCa. However, Uc.416+A was only overexpressed in GC and we identified an miR-153 binding site in the possible regulatory region of Uc.416+A using online databases. Along with a forced expression or knockdown of miR-153 in MKN-74 GC cells, the transcriptional levels of Uc.416+A were significantly disturbed. A luciferase reporter gene assay supported the direct regulation of Uc.416+A expression by miR-153. Furthermore, Uc.416+A was associated with cell growth through the regulation of IGFBP6 (insulin-like growth factor-binding protein 6) in GC. These findings suggest an oncogenic role of Uc.416+A in GC, which suggests that our approach would provide new insights into functional studies of T-UCRs in cancer biology.

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Objectives:To assess the long-term outcomes of transrectal high-intensity focused ultrasound (HIFU) for patients with localized prostate cancer. Methods: From May 2003 to present, 137 consecutive patients with T1-2 prostate cancer were treated using the Sonablate 500 and then followed for more than 12 months after their last HIFU treatment. A prostate biopsy was routinely carried out at 6 months and serum prostate-specific antigen (PSA) was measured every 3 months after HIFU. Oncological outcomes as well as treatment-related complications were assessed. Disease-free survival (DFS) was judged using the Phoenix definition (PSA nadir + 2 ng/mL), negative histological findings and no local or distant metastasis. Results:The median follow up after HIFU was 36 months (range 12-84 months). No patients received adjuvant therapy during this period. The PSA nadir occurred at 2 months after HIFU and the median level was 0.07 ng/mL (0.01-2.01 ng/mL). Of the 133 patients who underwent prostate biopsy or transurethral resection of the prostate at 6 months or later after HIFU, six were positive for cancer cells (4.5%). There were no major postoperative complications, but urge incontinence (16 cases) and dysuria (33 cases) occurred after removal of the urethral catheter. The 5-year DFS rate was 78% based on these criteria, and 91%, 81% and 62% in the low-, intermediate-and high-risk group, respectively. Conclusions: HIFU represents an effective, repeatable and minimally invasive treatment. It is particularly effective for low-and intermediate-risk patients, and it should be considered as an option for localized prostate cancer.

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