Expression analysis of differentially expressed miRNAs in male and female chicken embryos

MicroRNAs (miRNAs) are small non-coding RNA molecules that play key roles in the regulation of development processes of many tissues and organs at the post-transcriptional level. However, little is known about how they affect chicken gonadal development. We examined the expression of four miRNAs (miR-218, -200b, -196, and -206) in chicken embryonic gonads at embryonic days 3.5-6.5. Their target genes were predicted by miRDB, TargetScan and PicTar algorithms. The expression levels of these four miRNAs differed with sex to varying degrees; miR-200b was expressed at a significantly higher level in female gonads during the entire interval. The whole mount in situ hybridization result showed considerably higher expression of miR-200b in females than in males in E5.5 embryos. The miRNA target scanning results indicated several genes with functions in gonad development and gonad function. We conclude that miR-200b is involved in the regulation of gonad development and sexual differentiation of chicken embryos.

Poly(3-hexylthiophene) nanostructured materials for organic electronics applications

Semiconducting polymers have been developed during the last few decades and are currently used in various organic electronics applications. Regioregular poly(3-hexylthiophene) (P3HT) is the most employed semiconducting polymer for organic electronics applications. The development of living Grignard metathesis polymerization (GRIM) allowed the synthesis of P3HT with well-defined molecular weights and functional end groups. A large number of block copolymers containing P3HT have been reported, and their opto-electronic properties have been investigated. The performance of P3HT homopolymer and block copolymers in field-effect transistors and bulk heterojunction solar cells are discussed in this review. The morphology of the P3HT materials is also discussed.

Loss of p53 and altered miR15-a/16-1MCL-1 pathway in CLL: insights from TCL1-Tg:p53(-/-) mouse model and primary human leukemia cells

Chronic lymphocytic leukemia (CLL) patients with deletion of chromosome 17p, where the p53 gene is located, often develop more aggressive disease with poor clinical outcomes. To investigate the underlying mechanisms for the highly malignant phenotype of 17p- CLL and to facilitate in vivo evaluation of potential drugs against CLL with p53 deletion, we have generated a mouse model with TCL1-Tg:p53(-/-) genotype. These mice develop B-cell leukemia at an early age with an early appearance of CD5+ / IgM+ B cells in the peritoneal cavity and spleen, and exhibit an aggressive path of disease development and drug resistance phenotype similar to human CLL with 17p deletion. The TCL1-Tg:p53(-/-) leukemia cells exhibit higher survival capacity and are more drug resistant than the leukemia cells from TCL1-Tg:p53wt mice. Analysis of microRNA expression reveals that p53 deletion resulted in a decrease of miR-15a and miR-16-1, leading to an elevated expression of Mcl-1. Primary leukemia cells from CLL patients with 17p deletion also show a decrease in miR-15a/miR-16-1 and an increase in Mcl-1. Our study suggests that the p53/miR15a/16-1/Mcl-1 axis may be an important pathway that regulates Mcl-1 expression and contributes to drug resistance and aggressive phenotype in CLL cells with loss of p53.

Distinct long-term neurocognitive outcomes after equipotent sevoflurane or isoflurane anaesthesia in immature rats

BACKGROUND

Many anaesthetics when given to young animals cause cell death and learning deficits that persist until much later in life. Recent attempts to compare the relative safety or toxicity between different agents have not adequately controlled for the relative dose of anaesthetic given, thereby making direct comparisons difficult.

METHODS

Isoflurane or sevoflurane were given at 1 minimum alveolar concentration (MAC) for 4 h to postnatal day 7 (P7) rat pups. Beginning at P75 these animals underwent fear conditioning and at P83 Morris water maze testing to assess working memory, short-term memory and early long-term memory using delays of 1 min, 1 h, and 4 h.

RESULTS

No difference between groups was seen in fear conditioning experiments. Morris water maze learning was equivalent between groups, and no difference was seen in working memory. Sevoflurane-treated animals had a deficit in early long-term memory, and isoflurane-treated animals had a deficit in both short-term and early long-term memory.

CONCLUSIONS

Both isoflurane and sevoflurane delivered at 1 MAC for 4 h to immature rats caused a deficit in long-term memory. Isoflurane also caused a deficit in short-term memory. Isoflurane might be more detrimental than sevoflurane in very young animals.

CpG ODN-induced matrix metalloproteinase-13 expression is mediated via activation of the ERK and NF-κB signalling pathways in odontoblast cells

AIM

To investigate the effects of CpG ODN (CpG oligodeoxynucleotides) to model the action of bacterial challenge on pulpal matrix metalloproteinase-13 (MMP-13) expression and elucidate the associated intracellular signalling pathways.

METHODOLOGY

Real-time PCR was used to detect the effects of CpG ODN on MMP-13 mRNA expression levels in a murine odontoblast-lineage cell line (OLCs). The possible involvement of TLR9/MyD88, NF-κB or MAPK pathways involved in the CpG ODN-induced MMP-13 expression was examined by real-time PCR, transient transfection, luciferase activity assay and ELISA. Western blotting was performed to assay the phosphorylation of ERK at a range of time points.

RESULTS

MMP-13 was constitutively expressed in OLCs, and their exposure to CpG ODN significantly increased MMP-13 expression. Pre-treatment of OLCs with the inhibitory peptide MyD88, or chloroquine, attenuated the CpG ODN-induced expression of MMP-13. Treatment of the OLCs with CpG ODN increased NF-κB-luciferase activity. This activity was decreased by the over-expression of a nondegrading mutant of IκBα (IκBαSR), although enhanced by the over-expression of NF-κB p65. MMP-13 expression induced by CpG ODN was markedly suppressed by NF-κB inhibitors (pyrrolidine dithiocarbamate, PDTC), IκBα phosphorylation inhibitors (Bay 117082) or IκB protease inhibitor (L-1-tosylamido-2-phenylethyl chloromethyl ketone, TPCK). The inhibitor of ERK1/2, U0126, but not inhibitors of p38 MAPK and JNK, SB203580 and SP600125, decreased CpG ODN-mediated MMP-13 expression.

CONCLUSION

The CpG ODN-induced MMP-13 expression in OLCs is mediated through TLR9, NF-κB and the ERK pathway indicating that potentially the recognition of CpG ODN by TLR9 on odontoblasts may regulate the remodelling of injured dental pulp and hard tissues by inducing MMP-13 expression.

Abstract P2-05-05: Circulating HER2 extracellular domain (ECD) predicts a poor prognosis for metastatic breast cancer patients

Background: Amplification or overexpression of HER2 has been shown to play an important role in approximately 30% of breast cancers and is strongly associated with increased recurrence and a worse prognosis. The HER2 extracellular domain (ECD) may be cleaved and shed from the surface of breast cancer cells and serum HER2 ECD levels can be detected by enzyme-linked immunosorbent assay (ELISA). In this study, we explored the relationship between circulating HER2 ECD and tissue HER2 status, then we also examined its predictive value in a cohort of metastatic breast cancer patients.

Methods: Two hundred and seven metastatic breast cancer patients from March 2009 to July 2011 were involved in this prospective study at Zhejiang Cancer Hospital. The patients were identified histopathologically as having breast cancer by pathologists and staged mainly based on the pathology, the clinical manifestation, and the imaging findings of CT and MRI according to the classification system of the International Union Against Cancer. Serum HER2 ECD levels were measured by ELISA. Tissue HER2 was determined by IHC and FISH in tumor samples, respectively.

Results: The level of serum HER2 ECD was at least more than 15 ng/ml in 31.4% (65/207) metastatic breast cancer patients, 39.1%(43/110) in HER2-positive patients and 23.4%(22/94) in HER2-negative cases, respectively, P = 0.017. We also found that high serum HER2 ECD levels (≥15 ng/ml) were significantly associated with elevated serum CEA (52.1% v 21.5%, OR 3.978, 95%CI 2.138–7.401, P = 0.000), CA125 (48.5% v 23.5%, OR 3.064, 95%CI 1.650–5.691, P = 0.000), CA153 (53.2% v 17.1%, OR 5.48, 95%CI 2.897–10.366, P = 0.000), LDH (53.3% v 23.1%, OR 3.798, 95%CI 2.011–7.173, P = 0.000) and AKP (51.2% v 26.5%, OR 2.911, 95%CI 1.442–5.879, P = 0.002), respectively. For the effect of HER2 ECD on the site of relapse, still there were statistically significant correlation between increased serum HER2 ECD levels and liver involvement (42.7% v 24.0%, OR 2.358, 95%CI 1.294–4.297, P = 0.005), brain metastasis (50.0% v 26.7%, OR 2.744, 95%CI 1.397–5.391, P = 0.003) and visceral involved (37.9% v 14.8%, OR 3.511, 95%CI 1.548–7.961, P = 0.002), respectively. While serum HER2 ECD levels were not related to age, BMI, tumor size, lymph node involvement and hormone receptors status, respectively (P>0.05).

Conclusions: Monitoring the circulating levels of the HER2 ECD in patients with metastatic breast cancer provides a real-time assessment of tumor burden and indicates poor prognosis, and may provide important information for reassessment of HER2 in HER2-negative metastatic breast cancer.

Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr P2-05-05.

Comparison of double contrast-enhanced ultrasound and MDCT for assessing vascular involvement of pancreatic adenocarcinoma: preliminary results correlated with surgical findings

PURPOSE

To investigate the accuracy of double contrast-enhanced ultrasound (DCEUS) for assessing vascular involvement by pancreatic adenocarcinoma.

MATERIALS AND METHODS

38 patients with pancreatic adenocarcinoma proven by postoperative pathology or biopsy were enrolled in this study. DCEUS (intravenous microbubbles combined with an oral contrast agent) and 16-row multi-detector CT (MDCT) were performed preoperatively to assess vascular invasion by pancreatic adenocarcinoma. The diagnostic accuracy of DCEUS and MDCT for assessing vascular involvement was calculated and compared. ROC curves were used to evaluate the diagnostic confidences of the two methods. The inter- and intra-observer reliability of DCEUS for assessing vascular invasion was investigated in the present study.

RESULTS

Almost perfect agreement between DCEUS and MDCT was obtained using Kappa analysis (k = 0.83, p = 0.000). Compared with surgical findings, the sensitivity, specificity, positive predictive value, negative predictive value and accuracy of peripancreatic vascular invasion were 66.67 %, 100 %, 100 %, 60 %, and 77.78 %, respectively, for DCEUS and 75 %, 100 %, 100 %, 66.67 %, and 83.33 %, respectively, for MDCT. There was no significant difference in accuracy between DCEUS and MDCT for evaluating peripancreatic vascular invasion (p = 0.108). The combination of DCEUS and MDCT increased the diagnostic confidence in assessing peripancreatic vascular invasion with an area under ROC curve from 0.83 for DCEUS (p = 0.025) and 0.88 for MDCT (p = 0.011) to 0.92 for both combined (p = 0.005). The intra- and inter-observer reproducibility were both almost perfect for assessing the peripancreatic vascular invasion by DCEUS with a Kappa value of 0.94 (p = 0.000) for intra-observer and 0.83 (p = 0.000) for inter-observer.

CONCLUSION

DCEUS could be considered as a reliable and accurate method for evaluating the peripancreatic vascular invasion of pancreatic adenocarcinoma.

Preoperative T staging of advanced gastric cancer using double contrast-enhanced ultrasound

PURPOSE

To determine the accuracy of double contrast-enhanced ultrasound (DCEUS), in which intravenous microbubbles are used together with an oral contrast agent, in the preoperative T staging of advanced gastric cancer.

MATERIALS AND METHODS

This prospective, ethics committee-approved study recruited 350 patients who gave informed consent. All had gastric cancer proved by endoscopic biopsy and underwent preoperative ultrasound staging using the TNM classification (UICC 2002). The results of DCEUS were compared with postoperative pathologic findings. The staging accuracy of oral contrast-enhanced ultrasound (OCEUS) and DCEUS were compared to each other. Sensitivity and specificity for assessing serosal involvement by DCEUS were evaluated, and the concordance of this method was analyzed using Kappa statistics.

RESULTS

The accuracies of OCEUS and DCEUS in determining the T stage of advanced gastric cancer were 75.1 % (70.4 % for T2, 79.5 % for T3, 68.1 % for T4) and 87.4 % (83.3 % for T2, 89.7 % for T3, 87.2 % for T4), respectively, and the difference between the two methods was statistically significant (χ2 = 17.364, p< 0.001). The performance of DCEUS for staging lesions in the cardia (69.81 %), fundus (85.71 %) and body (85.56 %) had lower accuracy than that of other parts (93.94 % for antrum; 92.11 % for pylorus). Sensitivity and specificity for assessing serosal involvement by DCEUS were 98.76 % and 83.33 % respectively. The reliability was almost perfect with Kappa values of 0.89 (p< 0.001) for intra-observer and 0.82 (p< 0.001) for inter-observer agreement.

CONCLUSION

DCEUS could be considered as an accurate, non-invasive, and reliable diagnostic method for preoperative staging of advanced gastric cancer.

In-vitro antitumor-activity of the plant ribosome-inactivating proteins map-30 and gap-31

MAP 30 and GAP 31 are plant proteins isolated from Momordica charantia and Gelonium multiflorum, respectively. They have recently been shown to inhibit HIV-1 infection and replication. These proteins also possess a novel DNA topoisomerase-poison-like activity as well as ribosome inactivation. They were submitted to the Anti-Cancer Drug Screening Program of the National Cancer Institute and found to have potent anti-tumor activity against certain human tumor cell lines. The most sensitive cell lines responded to MAP 30 and GAP 31 with GI(50) that ranged from 0.01 to 10 mu g/ml and were unrelated to tumor type. These included cell lines from renal, non-small cell lung, and breast cancer. Targeted immunofusions made with MAP 30 or GAP 31 may be most effective toward these types of tumors.

Effect of the IGF-1/PTEN/Akt/FoxO signaling pathway in the duodenal mucosa of rats subjected to water immersion and restraint stress

The insulin growth factor 1/phosphatase and tensin homologue deleted on chromosome 10/Akt/forkhead box (IGF-1/PTEN/Akt/FoxO) signaling pathway reportedly exhibits gastroprotective effects by reducing water immersion and restraint stress (WRS)-induced gastric mucosal cell apoptosis. We examined the expression and localization of IGF-1, PTEN, Akt, and FoxO proteins, caspase-3 activity, and the number of apoptotic cells in the duodenal mucosa of rats subjected to WRS to confirm whether the IGF-1/PTEN/Akt/FoxO signaling pathway has a role in the duodenal mucosa. The results indicated that WRS enhanced cell apoptosis in the duodenal mucosa. In addition, in normal rats, PTEN was found mainly in the cellular cytoplasm of the duodenal glands and lamina propria of villi. IGF-1 and total Akt were observed in the cellular cytoplasm of the duodenal glands. In addition, total Akt was found in the cellular cytoplasm of the myenteric plexus. FoxO3a and FoxO4 were primarily concentrated in the cellular cytoplasm of the lamina propria. Specifically, PTEN, FoxO3a and FoxO4 were also localized in the cellular cytoplasm of lamina propria of restituted villi in the duodenal mucosa of rat subjected to WRS. In addition, messenger RNA transcript levels of IGF-1, PTEN, Akt1, Akt2, FoxO3, and FoxO4 were upregulated in the duodenal mucosa, with a peak between the 4th and 8th day after 7 h of WRS. Furthermore, the results also suggested that Akt3 messenger RNA transcript levels in the duodenal mucosa of rats after WRS showed no significant differences compared with those in the non-WRS group. Collectively, our results implied that the IGF-1/ PTEN/Akt/FoxO signaling pathway was effective in regulating cellular apoptosis in the duodenal mucosa of rats after WRS.