Identifying the dose response relationship between seminal metal at low levels and semen quality using restricted cubic spline function.

Environmental exposure to metals, including essential and nonessential elements, may be related to semen quality. Our goal was to explore the continuous relationship between seminal metals and sperm parameters. A restricted cubic spline (RCS) was applied to automatic selection criteria to ascertain the optimal smoothing degree. We recruited 841 male volunteers from Henan Province, China. Eighteen seminal metals, namely Al, Cr, Mn, Cu, Zn, Se, As, Ni, Cd, Pb, Co, V, Rb, Ag, Ba, TI, Fe, and Li, and 21 semen parameters were detected. Seminal malondialdehyde (MDA) was also detected to express oxidative stress. We revealed a non-linear relationship of the vanadium and chromium exposure to semen parameters. There were inverse 'U' shapes found between seminal Cr and sperm concentrations, total sperm count, and semen quality. The best semen quality was observed when the seminal Cr concentration was 5.05 ppb, and an increase or decrease in chromium concentration led to decreased semen quality. The V concentration was associated with reduced sperm concentration, total sperm count, normal morphology, and progressive motility at high doses (V > 0.58 ppb). Seminal MDA had a strong adverse association with sperm motility parameters, such as curve line velocity (VCL) (P < 0.001), straight line velocity (VSL) (P = 0.004), velocity of average path (VAP) (P < 0.001), and lateral head movement (ALH) (P = 0.001), whereas it was adversely associated with seminal Zn (ß [95% confidence interval (CI)], -0.28(-0.41-0.16), P < 0.001) after adjusting for confounding factors. Our findings represent the curves of the dose-response relationship between seminal Cr, seminal V, and semen quality, in which seminal MDA was a good indicator of sperm movement. These models provide new insight into the dose-relationship between metal exposure and semen quality, and further investigation is needed to validate this.

Long noncoding RNA ABHD11-AS1 promote cells proliferation and invasion of colorectal cancer via regulating the miR-1254-WNT11 pathway.

The purpose of our study was to investigate the effects of the long noncoding RNA (lncRNA) ABHD11-AS1 on colorectal cancer (CRC) progression and further explore its possible underlying mechanisms. In the study, we found that ABHD11-AS1 was highly expressed in CRC tissues and cell lines. High ABHD11-AS1 expression was correlated with poor overall survival of patients with CRC. ABHD11-AS1 knockdown reduced CRC cell proliferation, in vitro invasion, and in vivo tumor growth. Investigation of the underlying mechanism showed that ABHD11-AS1 could act as a molecular sponge of miR-1254, and WNT11 was a downstream target of miR-1254 in CRC. Moreover, there was a negative association between ABHD11-AS1 expression (or WNT11) and miR-1254 in CRC tissues. The rescue assays showed that WNT11 overexpression partially rescued the effects of ABHD11-AS1 inhibition on CRC progression. Thus, we demonstrated that ABHD11-AS1 promotes CRC progression through the miR-1254-WNT11 pathway, which provides a new insight into the therapeutic strategies for CRC.

Low Serum Levels of miR-101 Are Associated with Poor Prognosis of Colorectal Cancer Patients After Curative Resection.

BACKGROUND Recent studies showed low expression of microRNA (miR)-101 in various malignancies. However, the association of serum miR-101 and colorectal cancer (CRC) remains unknown. We investigated diagnostic and prognostic significance of serum miR-101 in CRC. MATERIAL AND METHODS A total of 263 consecutive CRC patients and 126 healthy controls were enrolled in this study. Serum miR-101 levels were measured using real-time quantitative reverse transcription polymerase chain reactions. The association between serum miR-101 level and survival outcome was analyzed. RESULTS Serum miR-101 in CRC patients was significantly lower than in healthy volunteers (P<0.001). Low serum miR-101 level was significantly associated with advanced cancer stage. Moreover, survival analysis demonstrated that patients with a low serum miR-101 had poorer 5-year overall survival than patients with a high serum miR-101 level (p=0.041). Serum miR-101 level also were confirmed as an independent risk factor for CRC in multivariate analysis (hazard ratio, 1.468; 95%CI, 0.981-1.976; p<0.001). CONCLUSIONS Serum miR-101 level was significantly downregulated in CRC patients and was closely correlated with poor clinical outcome, suggesting that serum miR-101 might be a useful diagnostic and prognostic marker for CRC.

miR-144-3p Induces Cell Cycle Arrest and Apoptosis in Pancreatic Cancer Cells by Targeting Proline-Rich Protein 11 Expression via the Mitogen-Activated Protein Kinase Signaling Pathway.

microRNAs (miRNAs) have been proved to be involved in many events of tumor development and progression, including cell proliferation, cell apoptosis, and cell cycle arrest. However, the potential role of miR-144-3p in pancreatic cancer (PC) remains elusive. In this study, we demonstrated that miR-144-3p was decreased in PC tissues and PANC-1 cells, whereas proline-rich protein 11 (PRR11) was remarkably increased. miR-144-3p mimics were discovered to inhibit cell proliferation by arresting cells at the S-phase of the cell cycle, and inducing cell apoptosis in PANC-1 cells. The effects of miR-144-3p on cell proliferation and cell apoptosis were reversed after treatment with the miR-144-3p inhibitor. Furthermore, a luciferase activity assay indicated that miR-144-3p directly targeted PRR11 3'-UTR. Moreover, transfection with miR-144-3p mimics inhibited the expression of PRR11. miR-144-3p mimics also upregulated the expression of p-JNK and p-p38, whereas they downregulated the expression of p-ERK. The effects of miR-144-3p on mitogen-activated protein kinase pathway proteins were reversed by the miR-144-3p inhibitor. PRR11 overexpression attenuated the effect of miR-144-3p mimics on cell apoptosis and cell cycle arrest. The expression of caspase-3 was decreased by enhanced PRR11. In summary, our findings indicated that miR-144-3p induced cell cycle arrest and apoptosis in PC by targeting PRR11. Therefore, the targeting of miR-144-3p could serve as a potential therapeutic strategy for the treatment of PC.

TXNIP overexpression suppresses proliferation and induces apoptosis in SMMC7221 cells through ROS generation and MAPK pathway activation.

Thioredoxin binding protein (thioredoxin-interacting protein, TXNIP), known as vitamin D3 increase protein 1, has been identified as a tumor suppressor in various cancers such as pancreatic, breast, lung and thyroid cancer. However, the role of TXNIP in hepatocellular carcinoma cell proliferation and apoptosis remains unknown. In this study, we first used qRT-PCR, western blotting and immunohistochemistry to compare the expression of TXNIP between hepatocellular carcinoma tissues and tumor-adjacent normal liver tissues. In vitro, we explored the role of TXNIP in hepatocellular carcinoma progression via transfection of the pcDNA-3.1-TXNIP plasmid into SMMC7221 cells. Our results showed that the expression of TXNIP was significantly decreased in hepatocellular carcinoma tissues. Moreover, TXNIP over-expression inhibited hepatocellular carcinoma cell proliferation and induced apoptosis by triggering mitochondrial-mediated ROS generation and activating MAPK pathways. This study provides insight into the molecular mechanisms of TXNIP overexpression in liver cancer cell survival and apoptosis and indicated that TXNIP may be a novel promising agent for liver cancer treatment.

NOR1 promotes hepatocellular carcinoma cell proliferation and migration through modulating the Notch signaling pathway.

Hepatocellular carcinoma (HCC) is one of the most common malignant tumors worldwide. Previous studies have reported that the oxidored-nitro domain containing protein 1 (NOR1) is a novel tumor suppressor in several tumors. Recent evidence suggests that NOR1 is strongly expressed in HCC cells. However, its role and mechanism in HCC are unclear. In the current study, Western blot and qPCR detected strong NOR1 mRNA and protein expression in HepG2 and Hep3B cells. After transfection with NOR1 siRNA or pcDNA3.1-myc-his-NOR1, the proliferation and migration of HepG2 and Hep3B cells were analyzed in vitro. HepG2 or Hep3B cells overexpressing NOR1 showed an increased proliferation and migration, whereas siRNA-mediated silencing of NOR1 showed the opposite effect. Furthermore, NOR1 activated the Notch signaling pathway, indicated by increased levels of Notch1, NICD, Hes1, and Hey1 in protein. Importantly, the Notch inhibitor DAPT downregulated Notch activation and further enhanced siNOR1-induced reduction of cell proliferation and migration in HepG2 and Hep3B cells, whereas DAPT reversed the effect of NOR1 overexpression on cell proliferation and migration. In conclusion, these results indicate that NOR1 may be involved in the progression of HCC and thus may be a potential target for the treatment of liver cancer.

MicroRNA-708 is downregulated in hepatocellular carcinoma and suppresses tumor invasion and migration.

BACKGROUND: MicroRNA-708 (miR-708) has been identified as one of down-regulated miRNAs in hepatocellular carcinoma (HCC) tissues by Taqman miRNAs array and confirmed quantitatively by reverse transcription polymerase chain reaction (qRT-PCR). However, its involvement in HCC remains unclear. The aim of this study was to investigate the roles of miR-708 in carcinogenesis and cancer progression of HCC. MATERIALS AND METHODS: QRT-PCR was performed to detect the expression of miR-708 in 100 pairs of HCC and adjacent non cancerous tissues. Then, its associations with various clinicopathological features of HCC patients were statistically evaluated. After that, we also observed the effects of enforced miR-708 expression on migration and invasion of HCC cells in vitro. RESULT: Our data confirmed that the expression level of miR-708 in HCC tissues was significantly lower than those in adjacent non-cancerous tissues (P=0.001). In addition, low miR-708 expression was found to be closely correlated with high Edmondson-Steiner grading (P=0.02) and advanced Tumor Node Metastasis (TNM) stage (P=0.01). Furthermore, the enforced expression of miR-708 could suppress the migration and invasion of HCC cell lines in vitro. CONCLUSION: Our findings support that miR-708, which is frequently down-regulated in HCC, may contribute to the aggressive progression of HCC and inhibit HCC cell mobility. Further studies on the identification of its target genes are required to be performed.

Krüppel-like factor 4 acts as an oncogene in colon cancer stem cell-enriched spheroid cells.

Cancer stem cells (CSCs), a rare population in any type of cancers, including colon cancer, are tumorigenic. It has been thought that CSCs are responsible for cancer recurrence, metastasis, and drug resistance. Isolating CSCs in colon cancers is challenging, and thus the molecular mechanism regulating the self-renewing and differentiation of CSCs remains unknown. We cultured DLD-1 cells, one of types of cells derived from colon cancers, in serum-free medium to obtain spheroid cells. These cells possessed the characteristics of CSCs, with the expression of CD133, CD166, Lgr5, and ALDH1, higher capacities of chemo-resistance, migration, invasion, and tumorigenicity in vitro and in vivo than the adherent DLD-1 cells. Krüppel-like factor 4 (KLF4) is essential factor for maintaining self-renewal of adult and embryonic stem cells. It has been used to induce pluripotent stem cells (iPS) from somatic cells. Since KLF4 is expressed in colon cancer cells, we investigated its role in spheroid cells isolated from DLD-1 cells and found that KLF4 was overexpressed only in spheroid cells and reducing the expression of KLF4 by short-hairpin RNA significantly decreased the capacities of these cells to resist the chemicals, migrate, invade, and generate tumors in vitro and in vivo. The spheroid cells with reduced KLF4 expression also had decreased expression of CSCs markers and mesenchymal markers. Taken together, culturing DLD-1 cells in serum-free medium enriches CSCs and the expression of KLF4 is essential for the characteristics of CSCs in DLD-1; thus KLF4 can be a potential therapeutic target for treating colon cancer.