Background-Obesity is a major risk factor for the development of cardiovascular disease. Emerging evidence indicates that leptin, a protein encoded by the obesity gene, is linked with cardiac hypertrophy in obese humans and directly induces cardiomyocyte hypertrophy in vitro. However, the mechanisms by which leptin induces cardiomyocyte hypertrophy are poorly understood. Methods and Results-This study investigated how leptin contributes to cardiomyocyte hypertrophy. Cultured neonatal rat cardiomyocytes were used to evaluate the effects of leptin on hypertrophy. Both endothelin-1 (ET-1) and reactive oxygen species (ROS) levels were elevated in a concentration-dependent manner in cardiomyocytes treated with leptin for 4 hours compared with those cells without leptin treatment. ET-1 stimulated ROS production in a concentrationdependent manner in cardiomyocytes. The augmentation of ROS levels in cardiomyocytes treated with both leptin and ET-1 was reversed by a selective ET A receptor antagonist, ABT-627, and catalase, a hydrogen peroxide-decomposing enzyme. After treatment for 72 hours, leptin or ET-1 concentration-dependently increased total RNA levels, cell surface areas, and protein synthesis in cardiomyocytes, all of which were significantly inhibited by ABT-627 or catalase treatment. Conclusions-These findings indicate that leptin elevates ET-1 and ROS levels, resulting in hypertrophy of cultured neonatal rat cardiac myocytes. The ET-1-ET A -ROS pathway may be involved in cardiomyocyte hypertrophy induced by leptin. ET A receptor antagonists and antioxidant therapy may provide an effective means of ameliorating cardiac dysfunction in obese humans.

We have previously shown that dysregulation of miR-21 functioned as an oncomiR in breast cancer. The aim of the present study was to elucidate the mechanisms by which miR-21 regulate breast tumor migration and invasion. We applied pathway analysis on genome microarray data and target-predicting algorithms for miR-21 target screening, and used luciferase reporting assay to confirm the direct target. Thereafter, we investigated the function of the target gene phosphoinositide-3-kinase, regulatory subunit 1 (α) (PIK3R1), and detected PIK3R1 coding protein (p85α) by immunohistochemistry and miR-21 by RT-qPCR on 320 archival paraffin-embedded tissues of breast cancer to evaluate the correlation of their expression with prognosis. First, we found that PIK3R1 suppressed growth, invasiveness, and metastatic properties of breast cancer cells. Next, we identified the PIK3R1 as a direct target of miR-21 and showed that it was negatively regulated by miR-21. Furthermore, we demonstrated that p85α overexpression phenocopied the suppression effects of antimiR-21 on breast cancer cell growth, migration and invasion, indicating its tumor suppressor role in breast cancer. On the contrary, PIK3R1 knockdown abrogated antimiR-21-induced effect on breast cancer cells. Notably, antimiR-21 induction increased p85α, accompanied by decreased p-AKT level. Besides, antimiR-21/PIK3R1-induced suppression of invasiveness in breast cancer cells was mediated by reversing epithelial-mesenchymal transition (EMT). p85α downregulation was found in 25 (7.8%) of the 320 breast cancer patients, and was associated with inferior 5-year disease-free survival (DFS) and overall survival (OS). Taken together, we provide novel evidence that miR-21 knockdown suppresses cell growth, migration and invasion partly by inhibiting PI3K/AKT activation via direct targeting PIK3R1 and reversing EMT in breast cancer. p85α downregulation defined a specific subgroup of breast cancer with shorter 5-year DFS and OS, which may require more aggressive treatment.

1 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2017;46:1611-1618.

Introduction: Metastasis is the primary cause of lung cancer-related death. Nevertheless, the underlying molecular mechanisms and evolutionary patterns of lung cancer metastases are still elusive.Methods: We performed whole-exome sequencing for 40 primary tumors (PTs) and 61 metastases from 47 patients with lung cancer, of which 40 patients had paired PTs and metastases. The PT-metastasis genomic divergence, metastatic drivers, timing of metastatic dissemination, and evolutionary origins were analyzed using appropriate statistical tools and mathematical models.Results: There were various degrees of genomic heterogeneity when comparing the paired primary and metastatic lesions or comparing metastases of different sites. Multiple metastasis-selected/enriched genetic alterations were found, such as MYC amplification, NKX2-1 amplification, RICTOR amplification, arm 20p gain, and arm 11p loss, and these results were were also featured in a meta-analysis cross-validated using an independent cohort from Memorial Sloan-Kettering Cancer Center database. To elucidate the metastatic seeding time, we applied a metastatic model and found 61.1% of the tumors were late dissemination, in which the metastatic seeding happened approximately 2.74 years before clinical detection. One exception was lymph

The differences in dfs and os between those three subgroups were significant (all p < 0.05 in paired comparisons). Multivariate Cox regression showed that subtype and ypN staging adjusted by pcr were the only two independent factors predicting dfs. ConclusionsAxillary lymph node status after nac, adjusted for pcr in breast and axilla, predicts differential dfs in patients without prior sentinel lymph node biopsy. KEY WORDSBreast cancer, neoadjuvant chemotherapy, axillary restaging, pathologic complete response, prognosis

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We used methylation-sensitive restriction fingerprinting (MSRF) to identify novel CpG (5'-CG-3' palindrome; p, phosphate group)-rich sequences that are methylated differentially between the hepatocellular carcinoma (HCC) genomes and adjacent nontumorous liver tissues. A 199-base-pair sequence methylated in HCC tumor tissue was isolated and showed high homology to the 5' CpG island of the zinc fingers and homeoboxes protein 2 (ZHX2) gene. By using bisulfite sequencing, we confirmed that hypermethylation of the 5' CpG island of ZHX2 occurred in some HCC and HepG2 cell lines but not in 6 normal liver tissue samples. By using methylation-specific polymerase chain reaction, we detected methylation of the 5' CpG island of ZHX2 in 46.9% of the HCCs. Reverse transcription-polymerase chain reaction demonstrated that ZHX2 messenger RNA (mRNA) was expressed in all 6 normal liver tissue samples but in only 13.3% of the methylated HCCs. Treatment of HepG2 with 5-aza-deoxycytidine could demethylate the promoter and increase ZHX2 mRNA expression. These results suggest that hypermethylation-mediated silencing of ZHX2 is an epigenetic event involved in HCC.

We used methylation-sensitive restriction fingerprinting (MSRF) to identify novel CpG (5'-CG-3' palindrome; p, phosphate group)-rich sequences that are methylated differentially between the hepatocellular carcinoma (HCC) genomes and adjacent nontumorous liver tissues. A 199-base-pair sequence methylated in HCC tumor tissue was isolated and showed high homology to the 5' CpG island of the zinc fingers and homeoboxes protein 2 (ZHX2) gene. By using bisulfite sequencing, we confirmed that hypermethylation of the 5' CpG island of ZHX2 occurred in some HCC and HepG2 cell lines but not in 6 normal liver tissue samples. By using methylation-specific polymerase chain reaction, we detected methylation of the 5' CpG island of ZHX2 in 46.9% of the HCCs. Reverse transcription-polymerase chain reaction demonstrated that ZHX2 messenger RNA (mRNA) was expressed in all 6 normal liver tissue samples but in only 13.3% of the methylated HCCs. Treatment of HepG2 with 5-aza-deoxycytidine could demethylate the promoter and increase ZHX2 mRNA expression. These results suggest that hypermethylation-mediated silencing of ZHX2 is an epigenetic event involved in HCC.