Transcriptome and DNA Methylation Responses in the Liver of Yellowfin Seabream Under Starvation Stress.

Fish suffer from starvation due to environmental risks such as extreme weather in the wild and due to insufficient feedings in farms. Nutrient problems from short-term or long-term starvation conditions can result in stress-related health problems for fish. Yellowfin seabream (Acanthopagrus latus) is an important marine economic fish in China. Understanding the molecular responses to starvation stress is vital for propagation and culturing yellowfin seabream. In this study, the transcriptome and genome-wide DNA methylation levels in the livers of yellowfin seabream under 14-days starvation stress were analyzed. One hundred sixty differentially expressed genes (DEGs) by RNA-Seq analysis and 737 differentially methylated-related genes by whole genome bisulfite sequencing analysis were identified. GO and KEGG pathway enrichment analysis found that energy metabolism-related pathways such as glucose metabolism and lipid metabolism were in response to starvation. Using bisulfite sequencing PCR, we confirmed the presence of CpG methylation differences within the regulatory region of a DEG ppargc1a in response to 14-days starvation stress. This study revealed the molecular responses of livers in response to starvation stress at the transcriptomic and whole genome DNA methylation levels in yellowfin seabream.

First identification of two co-existing genome-wide significant sex quantitative trait loci (QTL) in red tilapia using integrative QTL mapping.

Red tilapia ( Oreochromis spp .) is one of the most popular fish in China due to its bright red appearance, fast growth rate, and strong adaptability. Understanding the sex determination mechanisms is of vital importance for the selection of all-male lines to increase aquacultural production of red tilapia. In this research, the genetic architecture for sex from four mapping populations ( n=1 090) of red tilapia was analyzed by quantitative trait loci (QTL)-seq, linkage-based QTL mapping, and linkage disequilibrium (LD)-based genome-wide association studies. Two genome-wide significant QTL intervals associated with sex were identified on ChrLG1 (22.4-23.9 Mb) and ChrLG23 (32.0-35.9 Mb), respectively. The QTL on ChrLG1 was detected in family 1 (FAM1), FAM2, and FAM4, and the other QTL on ChrLG23 was detected in FAM3 and FAM4. Four microsatellite markers located within the QTL were successfully developed for marker-assisted selection. Interestingly, three ( lpp, sox14, and amh) of the 12 candidate genes located near or on the two QTL intervals were abundantly expressed in males, while the remaining genes were more highly expressed in females. Seven genes ( scly, ube3a, lpp, gpr17, oca2, cog4, and atp10a) were significantly differentially expressed between the male and female groups. Furthermore, LD block analysis suggested that a cluster of genes on ChrLG23 may participate in regulating sex development in red tilapia. Our study provides important information on the genetic architecture of sex in red tilapia and should facilitate further exploration of sex determination mechanisms in this species.

Two variants on T2DM susceptible gene HHEX are associated with CRC risk in a Chinese population.

Increasing amounts of evidence has demonstrated that T2DM (Type 2 Diabetes Mellitus) patients have increased susceptibility to CRC (colorectal cancer). As HHEX is a recognized susceptibility gene in T2DM, this work was focused on two SNPs in HHEX, rs1111875 and rs7923837, to study their association with CRC. T2DM patients without CRC (T2DM-only, n=300), T2DM with CRC (T2DM/CRC, n=135), cancer-free controls (Control, n=570), and CRC without T2DM (CRC-only, n=642) cases were enrolled. DNA samples were extracted from the peripheral blood leukocytes of the patients and sequenced by direct sequencing. The χ2 test was used to compare categorical data. We found that in T2DM patients, rs1111875 but not the rs7923837 in HHEX gene was associated with the occurrence of CRC (p= 0.006). for rs1111875, TC/CC patients had an increased risk of CRC (p=0.019, OR=1.592, 95%CI=1.046-2.423). Moreover, our results also indicated that the two variants of HEEX gene could be risk factors for CRC in general population, independent on T2DM (p< 0.001 for rs1111875, p=0.001 for rs7923837). For rs1111875, increased risk of CRC was observed in TC or TC/CC than CC individuals (p<0.001, OR= 1.780, 95%CI= 1.385-2.287; p<0.001, OR= 1.695, 95%CI= 1.335-2.152). For rs7923837, increased CRC risk was observed in AG, GG, and AG/GG than AA individuals (p< 0.001, OR= 1.520, 95%CI= 1.200-1.924; p=0.036, OR= 1.739, 95%CI= 0.989-3.058; p< 0.001, OR= 1.540, 95%CI= 1.225-1.936). This finding highlights the potentially functional alteration with HHEX rs1111875 and rs7923837 polymorphisms may increase CRC susceptibility. Risk effects and the functional impact of these polymorphisms need further validation.

Comparative Effectiveness of Risk-adapted Surveillance vs Retroperitoneal Lymph Node Dissection in Clinical Stage I Nonseminomatous Germ Cell Testicular Cancer: A Retrospective Follow-up Study of 81 Patients.

PURPOSE: To retrospective assess the potential predictors for relapse and create an effective clinical mode for surveillance after orchidectomy in clinical stage I non-seminomatous germ cell testicular tumors (CSI-NSGCTs). MATERIALS AND METHODS: We analyzed data for CSI-NSGCTs patients with non-lymphatic vascular invasion, %ECa < 50% (percentage of embryonal carcinoma < 50%), and negative or declining tumor markers to their half-life following orchidectomy (defined as low-risk patients); these patients were recruited from four Chinese centers between January 1999 and October 2013. Patients were divided into active surveillance group and retroperitoneal lymph node dissection (RPLND) group according to different therapeutic methods after radical orchidectomy was performed. The disease-free survival rates (DFSR) and overall survival rates (OSR) of the two groups were compared by Kaplan-Meier analysis. RESULTS: A total of 121 patients with CSI-NSGCT were collected from four centers, and 81 low-risk patients, including 54 with active surveillance and 27 with RPLND, were enrolled at last. The median follow-up duration was 66.2 (range 6-164) months in the RPLND group and 65.9 (range 8-179) months in the surveillance group. OSR was 100% in active surveillance and RPLND groups, and DFSR was 89.8% and 87.0%, respectively. No significant difference was observed between these two groups (X2=0.108, P=0.743). No significant difference was observed between the patients with a low percentage of embryonal carcinoma (<50%) and those without embryonal carcinoma (87.0% and 91.9%, X2=0.154, P=0.645). No treatment-related complications were observed in the active surveillance group whereas minor and major complications were observed in 13.0% and 26.1% of the RPLND group, respectively. CONCLUSIONS: Active surveillance resulted in similar DFSR and OSR compared with RPLND in our trial. Patients with low-risk CSI-NSGCTs could benefit from risk-adapted surveillance after these patients were subjected to radical orchidectomy.