E2F8-CENPL pathway contributes to homologous recombination repair and chemoresistance in breast cancer.

Chemoresistance poses a significant obstacle to the treatment of breast cancer patients. The increased capacity of DNA damage repair is one of the mechanisms underlying chemoresistance. Bioinformatic analyses showed that E2F8 was associated with cell cycle progression and homologous recombination (HR) repair of DNA double-strand breaks (DSBs) in breast cancer. E2F8 knockdown suppressed cell growth and attenuated HR repair. Accordingly, E2F8 knockdown sensitized cancer cells to Adriamycin and Cisplatin. Centromere protein L (CENPL) is a transcriptional target by E2F8. CENPL overexpression in E2F8-knockdowned cells recovered at least in part the effect of E2F8 on DNA damage repair and chemotherapy sensitivity. Consistently, CENPL knockdown impaired DNA damage repair and sensitized cancer cells to DNA-damaging drugs. These findings demonstrate that targeting E2F8-CENPL pathway is a potential approach to overcoming chemoresistance.

Abnormal ECG detection based on an adversarial autoencoder.

Automatic detection and alarm of abnormal electrocardiogram (ECG) events play an important role in an ECG monitor system; however, popular classification models based on supervised learning fail to detect abnormal ECG effectively. Thus, we propose an ECG anomaly detection framework (ECG-AAE) based on an adversarial autoencoder and temporal convolutional network (TCN) which consists of three modules (autoencoder, discriminator, and outlier detector). The ECG-AAE framework is trained only with normal ECG data. Normal ECG signals could be mapped into latent feature space and then reconstructed as the original ECG signal back in our model, while abnormal ECG signals could not. Here, the TCN is employed to extract features of normal ECG data. Then, our model is evaluated on an MIT-BIH arrhythmia dataset and CMUH dataset, with an accuracy, precision, recall, F1-score, and AUC of 0.9673, 0.9854, 0.9486, 0.9666, and 0.9672 and of 0.9358, 0.9816, 0.8882, 0.9325, and 0.9358, respectively. The result indicates that the ECG-AAE can detect abnormal ECG efficiently, with its performance better than other popular outlier detection methods.

Protective effect of diminazene attenuates myocardial infarction in rats via increased inflammation and ACE2 activity.

The present study aimed to investigate whether diminazene attenuates myocardial infarction (MI) in rats. In addition, the present study investigated whether ACE2 signaling was involved in the effects of diminazene on protein function. A rat model of acute myocardial infarction (AMI) was established by occlusion of the left anterior descending coronary artery. The AMI model rats received intraperitoneal injections of diminazene (5 mg/kg/day) for 3 days. Treatment with diminazene significantly inhibited the expression of casein kinase and lactate dehydrogenase, and reduced infarct size in AMI rats. The findings indicated that diminazene significantly reduced the levels of inflammatory factors including tumor necrosis factor­α and interleukin­6, suppressed the protein expression of cytochrome c oxidase subunit 2 (COX­2) and inducible nitric oxide synthase (iNOS), and activated angiotensin­converting enzyme 2 (ACE2), angiotensin II receptor type 1 (AT1R) and MAS1 proto­oncogene, G protein­coupled receptor (MasR) protein expression in AMI model rats. In conclusion, the present study demonstrated that diminazene attenuated AMI in rats via suppression of inflammation, reduction of COX­2 and iNOS expression, and activation of the ACE2/AT1R/MasR signaling pathway.

Establishment of a gastric cancer subline with high metastatic potential using a novel microfluidic system.

Metastasis is an important hallmark of malignant tumors. In this study, we developed a microfluidic system to screen highly metastatic sublines via differential resolution of cell invasiveness. The system was composed of a PDMS-glass device connected with a syringe pump and a Petri dish. To facilitate the selection process, a long-term cell invasion driving force based on a chemotactic factor gradient was created using the Petri dish-based liquid supply pattern, and the invasive cells were collected for round-by-round selection via an open region in the chip. Using the system, we established an SGC-7901/B2 subline from the human gastric cancer SGC-7901 cell line by only two rounds of selection. In vitro assays showed that the SGC-7901/B2 cells were superior to the parental cells in proliferation and invasiveness. Furthermore, an in vivo tumorigenicity assay demonstrated that compared with the parental cells, the subline had stronger spontaneous metastatic and proliferative capability, which led to a shorter survival duration. Additionally, the protein expression differences including E-cadherin and Smad3 between the subline and parental cells were revealed. In conclusion, this microfluidic system is a highly effective tool for selecting highly metastatic sublines, and SGC-7901/B2 cells could serve as a potential model for tumor metastasis research.

PCR-based assays versus direct sequencing for evaluating the effect of KRAS status on anti-EGFR treatment response in colorectal cancer patients: a systematic review and meta-analysis.

BACKGROUND: The survival rate of colorectal cancer (CRC) patients carrying wild-type KRAS is significantly increased by combining anti-EGFR monoclonal antibody (mAb) with standard chemotherapy. However, conflicting data exist in both the wild-type KRAS and mutant KRAS groups, which strongly challenge CRC anti-EGFR treatment. Here we conducted a meta-analysis in an effort to provide more reliable information regarding anti-EGFR treatment in CRC patients. METHODS: We searched full reports of randomized clinical trials using Medline, the American Society of Clinical Oncology (ASCO), and the European Society for Medical Oncology (ESMO). Two investigators independently screened the published literature according to our inclusive and exclusive criteria and the relative data were extracted. We used Review Manager 5.2 software to analyze the data. RESULTS: The addition of anti-EGFR mAb to standard chemotherapy significantly improved both progression-free survival (PFS) and median overall survival (mOS) in the wild-type KRAS group; hazard ratios (HRs) for PFS and mOS were 0.70 [95% confidence interval (CI), 0.58-0.84] and 0.83 [95% CI, 0.75-0.91], respectively. In sub-analyses of the wild-type KRAS group, when PCR-based assays are employed, PFS and mOS notably increase: the HRs were 0.74 [95% CI, 0.62-0.88] and 0.87 [95% CI, 0.78-0.96], respectively. In sub-analyses of the mutant KRAS group, neither PCR-based assays nor direct sequencing enhance PFS or mOS. CONCLUSION: Our data suggest that PCR-based assays with high sensitivity and specificity allow accurate identification of patients with wild-type KRAS and thus increase PFS and mOS. Furthermore, such assays liberate patients with mutant KRAS from unnecessary drug side effects, and provide them an opportunity to receive appropriate treatment. Thus, establishing a precise standard reference test will substantially optimize CRC-targeted therapies.

Detection of low-abundance KRAS mutations in colorectal cancer using microfluidic capillary electrophoresis-based restriction fragment length polymorphism method with optimized assay conditions.

Constitutively active KRAS mutations have been found to be involved in various processes of cancer development, and render tumor cells resistant to EGFR-targeted therapies. Mutation detection methods with higher sensitivity will increase the possibility of choosing the correct individual therapy. Here, we established a highly sensitive and efficient microfluidic capillary electrophoresis-based restriction fragment length polymorphism (µCE-based RFLP) platform for low-abundance KRAS genotyping with the combination of µCE and RFLP techniques. By using our self-built sensitive laser induced fluorescence (LIF) detector and a new DNA intercalating dye YOYO-1, the separation conditions of µCE for ΦX174 HaeIII DNA marker were first optimized. Then, a Mav I digested 107-bp KRAS gene fragment was directly introduced into the microfluidic device and analyzed by µCE, in which field amplified sample stacking (FASS) technique was employed to obtain the enrichment of the RFLP digestion products and extremely improved the sensitivity. The accurate analysis of KRAS statuses in HT29, LS174T, CCL187, SW480, Clone A, and CX-1 colorectal cancer (CRC) cell lines by µCE-based RFLP were achieved in 5 min with picoliter-scale sample consumption, and as low as 0.01% of mutant KRAS could be identified from a large excess of wild-type genomic DNA (gDNA). In 98 paraffin-embedded CRC tissues, KRAS codon 12 mutations were discovered in 28 (28.6%), significantly higher than that obtained by direct sequencing (13, 13.3%). Clone sequencing confirmed these results and showed this system could detect at least 0.4% of the mutant KRAS in CRC tissue slides. Compared with direct sequencing, the new finding of the µCE-based RFLP platform was that KRAS mutations in codon 12 were correlated with the patient's age. In conclusion, we established a sensitive, fast, and cost-effective screening method for KRAS mutations, and successfully detected low-abundance KRAS mutations in clinical samples, which will allow provision of more precise individualized cancer therapy.

A novel bisulfite-microfluidic temperature gradient capillary electrophoresis platform for highly sensitive detection of gene promoter methylation.

The hypermethylated tumor suppressor gene promoters are widely recognized as promising markers for cancer screening and ideal targets for cancer therapy, however, a major obstacle in their clinical study is highly sensitive screening. To address this limitation, we developed a novel bisulfite-microfluidic temperature gradient capillary electrophoresis (bisulfite-µTGCE) platform for gene methylation analysis by combining bisulfite treatment and slantwise radiative heating system-based µTGCE. Bisulfite-treated genomic DNA (gDNA) was amplified with universal primers for both methylated and unmethylated sequences, and introduced into glass microfluidic chip to perform electrophorectic separation under a continuous temperature gradient based on the formation of heteroduplexes. Eight CDKN2A promoter model fragments with different number and location of methylation sites were prepared and successfully analyzed according to their electrophoretic peak patterns, with high stability, picoliter-scale sample consumption, and significantly increased detection speed. The bisulfite-µTGCE could detect methylated gDNA with a detection limit of 7.5pg, and could distinguish as low as 0.1% methylation level in CDKN2A in an unmethylated background. Detection of seven colorectal cancer (CRC) cell lines with known and unknown methylation statuses of CDKN2A promoter and 20 tumor tissues derived from CRC patients demonstrated the capability of detecting hypermethylation in real-world samples. The wider adaptation of this platform was further supported by the detection of the CDKN2A and MLH1 promoters' methylation statuses in combination. This highly sensitive, fast, and low-consumption platform for methylation detection shows great potential for future clinical applications.

[Study on the relationship between copper, lysyl oxidase and premature rupture of membranes].

OBJECTIVE: To determine the relationships between maternal serum copper, amniotic copper, lysyl oxidase (LOX) and collagen III in pregnant women with premature rupture of membranes (PROM) and without PROM. METHODS: One hundred women with PROM were enrolled in this study, and divided into 37-42 weeks, 34-36(+6) weeks and 28-33(+6) weeks according to gestational age. One hundred non-PROM pregnancies matching the same gestational ages were recruited as control group. Copper of maternal serum and amnion in two groups were compared by FAAS method. Amniotic LOX was analyzed by fluorometry. Amniotic collagen III was detected by immunohistochemical method and computer image analysis system (absorbance, A). Linear correlation analysis was used to explore the relationships between maternal serum copper, amniotic copper, LOX and collagen III. RESULTS: (1) For 37-42 weeks pregnant women, serum copper was correlated positively with amniotic copper in two groups, r = 0.82 (P < 0.001), but for other parameters, the serum and amniotic levels had no correlations. (2) For 34-36(+6) and 28 - 33(+6) weeks pregnant women, there were positive correlations between serum copper, amniotic copper, LOX and collagen III in two groups (P < 0.01). (3) For 37-42 weeks pregnant women, serum copper and amniotic copper had no difference between two groups (P > 0.05), but amniotic LOX and collagen III decreased significantly compared with controls, being [(0.53 +/- 0.10) microg/g vs (0.75 +/- 0.10) microg/g, P < 0.01], (0.36 +/- 0.01 vs 0.37 +/- 0.01, P < 0.05) respectively. (4) For 34 - 36(+6) weeks pregnant women, serum copper, amniotic copper, LOX and collagen III reduced obviously between two groups (P < 0.01), being respectively [(115.23 +/- 9.56) mg/L vs (139.03 +/- 10.59) mg/L], [(0.21 +/- 0.04) microg/mg vs (0.29 +/- 0.04) microg/mg], [(0.54 +/- 0.10) microg/g vs (0.70 +/- 0.13) microg/g], and (0.36 +/- 0.01 vs 0.37 +/- 0.01). (5) For 28-33(+6) weeks pregnant women, serum copper, amniotic copper, LOX and collagen III also reduced obviously between two groups (P < 0.01), [(120.31 +/- 8.04) microg/L vs (136.40 +/- 8.21) microg/L], [(0.21 +/- 0.04) microg/mg vs (0.26 +/- 0.03) microg/mg], [(0.62 +/- 0.09) microg/g vs (0.72 +/- 0.09) microg/g], and (0.35 +/- 0.01 vs 0.38 +/- 0.01). CONCLUSION: For term pregnant women, the decreases of amniotic LOX and collagen III in PROM group are not affected by serum copper, perhaps by excessive degeneration of amnion; for non-term pregnant women, the decreases of serum copper, amniotic copper, LOX and collagen III are correlated directly with PROM.