Search

Salicylic acid (SA) is a plant hormone involved in a series of growth, development, and stress responses in plants. Nonexpressor of pathogenesis-related genes 1 (NPR1) is the core regulatory gene in the process of SA-mediated SAR. Whether NPR1 is involved in pollen tube growth mediated by SA and its derivative MeSA (methyl salicylate) remains to be explored. Here we found that the contents of endogenous SA and MeSA in self- or cross-pollinated pistils changed significantly, and exogenous SA and MeSA significantly promoted pollen germination and pollen tube elongation of Camellia oleifera at lower concentrations. CoNPR1, CoNPR3.1, CoNPR3.2, and CoNPR5 were identified, and they were all located in the nucleus. A high level of consistency was observed across the phylogenetic relationships, gene structures, and functional domains, indicating a clear division of function, as observed in other species. The expression level of CoNPR1, CoNPR3.1, CoNPR3.2, and CoNPR5 in self- and cross-pollinated pistil had certain regularity. Furthermore, they exhibited tissue specific expression pattern. CoNPR1 and CoNPR3.1 were expressed in pollen tubes, whose expression was regulated by SA or MeSA, and their expression patterns were basically consistent with the trend of pollen germination. These results indicate that SA and MeSA are involved in the pollen tube growth of C. oleifera, and CoNPRs may play an important role therein. This article is protected by copyright. All rights reserved.

CircRNA is a kind of covalent head-to-tail looped RNA and plays an important role in tumor development. However, the identification of new potential targetable circRNAs to inhibit cancer development is still a huge challenge. In this study, we found that circEHMT1 inhibited migration and invasion of breast cancer cells. Mechanistically, we identified miR-1233-3p as a target of circEHMT1, and the circEHMT1/miR-1233-3p axis regulated matrix metalloprotease 2 (MMP2) by modulating the transcription factor Krϋppel-like factor 4 (KLF4). In summary, we showed that circEHMT1 has potential as a prognostic factor in breast cancer and played a tumor suppressor role via the circEHMT1/miR-1233-3p/KLF4/MMP2 axis.

Background Caseinolytic protease P (ClpP), which is located on the inner mitochondrial membrane, degrades mitochondrial proteins damaged by oxidative stress. The role of ClpP varies among tumor types. However, the expression pattern and biological functions of ClpP in breast cancer (BC) have not yet been investigated. Methods The Cancer Genome Atlas (TCGA) and Kaplan Meier-plotter database were used to analyze the expression level of ClpP in BC tissues, relationships with clinicopathological characteristics, and the influence on the prognosis of BC. Protein and mRNA expression levels of ClpP in BC cell lines and tissues were detected by quantitative real-time PCR, western blot and immunohistochemical (IHC) analyses. The colony formation assay, transwell assay and flow cytometric analysis were performed to assess various functions of ClpP. Western blot analysis was also conducted to determine the mechanism of ClpP. Results ClpP expression was markedly increased in BC cells and tissues. High expression of ClpP was significantly correlated with the T stage, estrogen receptor (ER) expression, and poor recurrence-free survival (RFS) in TCGA and Kaplan Meier-plotter database. ClpP silencing significantly inhibited proliferation, migration, invasion, and promoted apoptosis of BC cells, which resulted in suppression of the Src/PI3K/Akt signaling pathway. The gain-of-function assay confirmed partial these results.

Oil-tea tree (Camellia oleifera) is the most important edible oil tree species in China with late-acting self-incompatibility (LSI) properties. The mechanism of LSI is uncertain, which seriously hinders the research on its genetic characteristics, construction of genetic map, selection of cross breeding parents and cultivar arrangement. To gain insights into the LSI mechanism, we performed cytological, transcriptomic, proteomic and metabolomic studies on self- and cross-pollinated pistils. The studies identified 166,591 transcripts, 6851 proteins and 6455 metabolites. Transcriptomic analysis revealed 1197 differentially expressed transcripts between self- and cross-pollinated pistils and 47 programmed cell death (PCD)-control transcripts. Trend analysis by Pearson correlation categorized nine trend graphs linked to 226 differentially expressed proteins and 38 differentially expressed metabolites. Functional enrichment analysis revealed that the LSI was closely associated with PCD-related genes, mitogen-activated protein kinase (MAPK) signaling pathway, plant hormone signal transduction, ATP-binding cassette (ABC) transporters and ubiquitin-mediated proteolysis. These particular trends in transcripts, proteins and metabolites suggested the involvement of PCD in LSI. The results provide a solid genetic foundation for elucidating the regulatory network of PCD-mediated self-incompatibility in C. oleifera.

Alterations in the ubiquitin-proteasome system (UPS) and UPS-associated proteins have been implicated in the development of many human malignancies. In this study, we investigated the expression profiles of 797 UPS-related genes using HiSeq data from The Cancer Genome Atlas and identified that PSMD2 was markedly upregulated in breast cancer. High PSMD2 expression was significantly correlated with poor prognosis. Gene set enrichment analysis revealed that transcriptome signatures involving proliferation, cell cycle, and apoptosis were critically enriched in specimens with elevated PSMD2. Consistently, PSMD2 knockdown inhibited cell proliferation and arrested cell cycle at G0/G1 phase in vitro, as well as suppressed tumor growth in vivo. Rescue assays demonstrated that the cell cycle arrest caused by silencing PSMD2 partially resulted from increased p21 and/or p27. Mechanically, PSMD2 physically interacted with p21 and p27 and mediated their ubiquitin-proteasome degradation with the cooperation of USP14. Notably, intratumor injection of therapeutic PSMD2 small interfering RNA effectively delayed xenograft tumor growth accompanied by p21 and p27 upregulation. These data provide novel insight into the role of PSMD2 in breast cancer and suggest that PSMD2 may be a potential therapeutic target.

// Yunhai Li 1, 2 , Jing Huang 1 , Jiazheng Sun 1 , Shili Xiang 1 , Dejuan Yang 1, 2 , Xuedong Ying 1, 2 , Mengqi Lu 1 , Hongzhong Li 1, 2 , Guosheng Ren 1, 2 1 Chongqing Key Laboratory of Molecular Oncology and Epigenetics, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China 2 Department of Endocrine and Breast Surgery, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China Correspondence to: Hongzhong Li, email: tibetlhz@126.com Guosheng Ren, email: rengs726@126.com Keywords: proteasome alpha subunits, cancer, oncomine, TCGA, Kaplan-Meier plotter Received: June 19, 2016 Accepted: December 01, 2016 Published: December 10, 2016 ABSTRACT Proteasome alpha subunits (PSMAs) have been shown to participate in the malignant progression of human cancers. However, the expression patterns and prognostic values of individual PSMAs remain elusive in most cancers. In the present study, we investigated the mRNA expression levels of seven PSMAs in different kinds of cancers using Oncomine and The Cancer Genome Atlas (TCGA) databases. The prognostic significance of PSMAs was also determined by Kaplan-Meier Plotter and PrognScan databases. Combined with Oncomine and TCGA, the mRNA expression levels of PSMA1-7 were significantly upregulated in breast, lung, gastric, bladder and head and neck cancer compared with normal tissues. Moreover, only PSMA6 and PSMA5 were not overexpressed in colorectal and kidney cancer, respectively. In survival analyses based on Kaplan-Meier Plotter, PSMA1-7 showed significant prognostic values in breast, lung and gastric cancer. Furthermore, potential correlations between PSMAs and survival outcomes were also observed in ovarian cancer, colorectal cancer and melanoma by Kaplan-Meier Plotter and PrognScan. These data indicated that PSMAs might serve as novel biomarkers and potential therapeutic targets for multiple human cancers. However, further studies are needed to explore the detailed biological functions and molecular mechanisms involved in tumor progression.

The abnormal expression of microRNAs is a key hallmark of breast cancer. Nevertheless, the biological roles of miR-1247-5p in breast cancer remain unknown. In this study, we revealed that miR-1247-5p expression was markedly decreased in breast cancer. It was a valuable diagnostic biomarker for breast cancer with the area under the curve of more than 0.80. Reduced miR-1247-5p expression was significantly correlated with patient age, tumor size, and poor prognosis in The Cancer Genome Atlas cohort including 839 breast cancer patients. Multivariate Cox regression analysis demonstrated that miR-1247-5p was an independent prognostic indicator for overall survival (hazard radio [HR] = 1.683, 95% confidence interval [CI] = 1.087-2.606, p = 0.020) and recurrence-free survival (HR = 2.496, 95% CI = 1.576-3.951, p 0.001). Moreover, functional studies showed that overexpression of miR-1247-5p inhibited proliferation and induced apoptosis in breast cancer cells. Bioinformatics analysis and mechanistic investigations revealed that Dishevelled 1 (DVL1) was a direct target of miR-1247-5p. Inhibition of DVL1 by miR-1247-5p resulted in the suppression of Wnt/β-catenin signaling, whereas overexpression of DVL1 abrogated the miR-1247-5p-mediated effect. These data reveal that miR-1247-5p, as an oncosuppressor in breast cancer, may be a promising prognostic biomarker and therapeutic target.