Clinical evaluation of a multitarget fecal immunochemical test-sDNA test for colorectal cancer screening in a high-risk population: a prospective, multicenter clinical study.

Colorectal cancer (CRC) is a major malignancy threatening the health of people in China and screening could be effective for preventing the occurrence and reducing the mortality of CRC. We conducted a multicenter, prospective clinical study which recruited 4,245 high-risk CRC individuals defined as having positive risk-adapted scores or fecal immunochemical test (FIT) results, to evaluate the clinical performance of the multitarget fecal immunochemical and stool DNA (FIT-sDNA) test for CRC screening. Each participant was asked to provide a stool sample prior to bowel preparation, and FIT-sDNA test and FIT were performed independently of colonoscopy. We found that 186 (4.4%) were confirmed to have CRC, and 375 (8.8%) had advanced precancerous neoplasia among the high CRC risk individuals. The sensitivity of detecting CRC for FIT-sDNA test was 91.9% (95% CI, 86.8-95.3), compared with 62.4% (95% CI, 54.9-69.3) for FIT (P < 0.001). The sensitivity for detecting advanced precancerous neoplasia was 63.5% (95% CI, 58.3-68.3) for FIT-sDNA test, compared with 30.9% (95% CI, 26.3-35.6) for FIT (P < 0.001). Multitarget FIT-sDNA test detected more colorectal advanced neoplasia than FIT. Overall, these findings indicated that in areas with limited colonoscopy resources, FIT-sDNA test could be a promising further risk triaging modality to select patients for colonoscopy in CRC screening.

Folate receptor-positive circulating tumor cells in predicting ground-glass nodules malignancy.

OBJECTIVE: To study the clinical significance of folate receptor-positive circulating tumor cells (FR+CTCs) in determining malignancy of ground-glass nodules (GGNs) and assess the added value of FR+CTC in the classic GGN evaluation model (Mayo Model). METHODS: Sixty-five patients with single indeterminate GGN were recruited. Twenty-two participants had benign/pre-malignant diseases, and forty-three had lung cancers, as confirmed by histopathology examination. FR+CTC was enumerated by CytoploRare® Kit. A CTC model was drawn based on the multivariate logistic analysis. The area under the receiver operating characteristic curve (AUC) was analyzed to evaluate the diagnostic performance of FR+CTC, CTC model and Mayo model. RESULTS: In the cohort, the mean age of 13 males and 9 females with benign/pre-malignant diseases was 57.7 ± 10.2 years. The mean age of 13 males and 30 females with lung cancers was 53.8 ± 11.7 years. There was no significant difference between the age and the smoking history (P=0.196 and P=0.847, respectively). FR+CTC can effectively differentiate lung cancer from benign/pre-malignant diseases [sensitivity: 88.4%, specificity: 81.8%, the AUCs was 0.8975, 95% confidence interval (CI): 0.8174-0.9775] in patients with GGN. Multivariate analysis revealed that FR+CTC level, tumor size, and tumor location were independent predictors of GGN malignancy (P<0.05). The prediction model based on these factors showed better diagnostic efficiency than the Mayo model (AUC: 0.9345 vs. 0.6823), yielding superior sensitivity (81.4% vs. 53.5%) and specificity (95.5% vs. 86.4%). CONCLUSION: The FR+CTC exhibited a promising potential in determining the malignancy of indeterminate GGNs, and the CTC model's diagnostic efficiency was superior to the Mayo model.

Circ8199 encodes a protein that inhibits the activity of OGT by JAK2-STAT3 pathway in esophageal squamous cell carcinoma.

Esophageal squamous cell carcinoma (ESCC) is an invasive malignant tumor with a high incidence rate and mortality. It is imperative to study its tumorigenesis and development for better treatment. CircRNA has been proven to play an important role in various cancers. Our previous studies found that the circ8199 gene is associated with tumor prognosis. To further clarify the role of circ8199 in ESCC, we performed functional experiments and found that overexpression of circ8199 significantly inhibited the proliferation of ESCC cells and the activity of O-linked N-acetylglucosamine transferase (OGT) simultaneously. Further experiments demonstrated that circ8199 could interact with OGT, leading to a decrease in OGT's activity. The reduction of circ8199 expression stimulated the binding activity between OGT and its downstream gene JAK2, promoting the O-GlcNAc glycosylation modification of JAK2 and activating the JAK2-STAT3 pathway. Our study indicated that circ8199 regulates the JAK2-STAT3 pathway through OGT, providing a candidate mechanism for drug discovery and development.

MicroRNA-134 prevents the progression of esophageal squamous cell carcinoma via the PLXNA1-mediated MAPK signalling pathway.

BACKGROUND: MicroRNAs (miRNAs) are involved in oncogenesis of esophageal squamous cell carcinoma (ESCC). miR-134 is reported to have a tumour-suppressive role but its role in ESCC is not known. The present study was designed to examine whether miR-134 inhibits ESCC development and further explored relevant underlying mechanisms. METHODS: Differentially expressed genes related to ESCC were identified from microarray gene expression profiles. Immunohistochemical staining and RT-qRCR assays identified elevated PLXNA1 expression levels and low miR-134. The relationship between miR-134 and PLXNA1 was predicted and further verified by a dual-luciferase reporter assay. The expression levels of miR-134 and PLXNA1 in ESCC cells were modified by miR-134 mimic/inhibitor and siRNA against PLXNA1, respectively. Thereafter, the expression of MAPK signalling pathway-related proteins, as well as the viability, migration, invasion, cell cycle and cell apoptosis of ESCC cells was investigated. FINDINGS: The results showed that miR-134 could block the MAPK signalling pathway by downregulating PLXNA1. When miR-134 was overexpressed or PLXNA1 was silenced, cell apoptosis was enhanced, the cell cycle was retarded, and the cell proliferation, migration and invasion were suppressed. In vivo experiments confirmed that miR-134 overexpression or PLXNA1 silencing restrained tumour growth and lymph node metastasis. INTERPRETATION: These findings demonstrate that cancer cell proliferation, migration, invasion, and tumour metastasis of ESCC can be suppressed by overexpression of miR-134 through downregulating PLXNA1, which subsequently blocks the MAPK signalling pathway. These results provide new potential targets and strategies for the treatment of ESCC.

Long Noncoding RNA HOST2 Promotes Epithelial-Mesenchymal Transition, Proliferation, Invasion and Migration of Hepatocellular Carcinoma Cells by Activating the JAK2-STAT3 Signaling Pathway.

BACKGROUND/AIMS: This study aims to examine the effect of long noncoding RNA HOST2 (LncRNA HOST2) on epithelial-mesenchymal transition (EMT), proliferation, invasion and migration of hepatocellular carcinoma (HCC) cells via activation of the JAK2-STAT3 signaling pathway. METHODS: HCC and para-cancerous tissues were collected from 136 HCC patients. Immunohistochemistry was used to detect the expression of JAK2 and STAT3. HCC SMMC7721 cells were grouped into blank, negative control (NC), HOST2 mimic and HOST2 inhibitor groups. The mRNA and protein expression levels of HOST2, JAK2, STAT3, E-cadherin, vimentin, Snail, Slug, Twist and Zeb1 in tissues and cells were determined by reverse transcription -quantitative polymerase chain reaction (RT-qPCR) and Western blotting, respectively. An MTT assay, scratch test and Transwell assay were applied to measure cell proliferation, migration and invasion, respectively. RESULTS: The levels of JAK2, STAT3 and vimentin were higher in HCC tissues, while the expression of E-cadherin was lower in HCC tissues compared with para-cancerous tissues. The silencing of HOST2 significantly decreased cell proliferation, migration and invasion, reduced the levels of HOST2, JAK2, STAT3 and vimentin, and elevated the expression of E-cadherin. HOST2 silencing also decreased the levels of Snail, Slug and Twist but increased the level of Zeb1 protein, while the opposite findings were observed in the HOST2 mimic group. CONCLUSION: These results reveal a possible mechanism in HCC in which LncRNA HOST2 may increase EMT and enhance proliferation, invasion and metastasis of HCC cells via activation of the JAK2-STAT3 signaling pathway.

The synergistic effect of esophageal squamous cell carcinoma KYSE150 cells and M2 macrophages on lymphatic endothelial cells.

Objective: This study aimed to investigate whether tumor-associated macrophages (TAMs) and esophageal squamous cell carcinoma (ESCC) cells could synergistically influence the generation of lymphatic vessels via the VEGF-C/VEGFR-3 signaling pathway and to address its mechanism. Methods: M2 macrophages were sorted with immunomagnetic beads and induced in vitro. VEGF-C siRNA plasmids were constructed and transfected into M2 macrophages and the ESCC cell line KYSE150. Different conditioned culture media before and after transfection were collected and classified into different groups for culturing ESCC-associated lymphatic endothelial cells (ESCC-LECs). Using the CCK-8 assay, Transwell cell migration assay and Matrigel three-dimensional culture, the proliferation, migration and ring forming abilities of ESCC-LECs before and after transfection were compared, respectively. With ELISA, western blot and q(RT)-PCR, VEGF-C concentrations in conditioned culture media and the protein and mRNA expression levels of VEGFR-3 in LECs before and after transfection were compared, respectively. Results: Before transfection, ESCC-LECs in the group with mixed culture medium had stronger proliferation, migration and ring forming abilities than the other groups. The VEGF-C concentration and VEGFR-3 protein and mRNA expression levels were higher in the mixed culture medium group than in the other groups. After transfection, all indices were the lowest in the mixed culture medium group. Conclusions: M2 macrophages can enhance the proliferation, migration and ring forming abilities of ESCC-LECs. ESCC cells and M2 macrophages have synergistic effects on the proliferation, migration and ring forming abilities of ESCC-LECs. VEGF-C siRNA can inhibit the proliferation, migration and ring forming abilities of ESCC-LECs by silencing the expression of VEGF-C and its receptor VEGFR-3 in KYSE150 cells and M2 macrophages.

[Antitumour efficacy of a novel oncolytic adenovirus Ad-TD-RFP for human nasopharyngeal carcinoma].

OBJECTIVE: To evaluate the antitumor efficacy of Ad-TD-RFP for human nasopharyngeal carcinoma cells (C666-1) in vitro and in vivo. METHODS: The oncolytic effects of Ad-TD-RFP and control virus dl11520 on C666-1 cells were determined by cytotoxicity assay (MTS assay). Viral replication of Ad-TD-RFP and dl11520 was detected at different time points (24 h, 48 h, 72 h and 96 h) by tissue culture infective dose (TCID(50)) in C666-1 cells implanted subcutaneously into the flank in each of BALB/c nude mice. The xenografts were injected intratumorally with Ad-TD-RFP or dl1520 to investigate their effects on tumor growth. RESULTS: The concentration for 50% of maximal effect (EC(50)) values of Ad-TD-RFP and dl1520 were (107.6 ± 3.2) pt/cell and (174.1 ± 4.0) pt/cell, respectively (t = 22.6, P < 0.001). The Ad-TD-RFP replication was 3-14 folds more than dl1520 replication at four time points (24 h, 48 h, 72 h and 96 h) in C666-1 cells (t values were 33.6, 23.4, 20.8 and 17.3, respectively, P < 0.001). The average tumor volumes of PBS group, dl1520 group and Ad-TD-RFP group were (1765.5 ± 713.9) mm(3), (1036.9 ± 623.8) mm(3), and (420.8 ± 238.7) mm(3), respectively (F = 12.0, P < 0.05) on day 67 after treatment. CONCLUSIONS: The antitumour efficacy of the novel oncolytic adenovirus Ad-TD-RFP for human nasopharyngeal carcinoma C666-1 cells is superior to that of dl1520 in vitro and in vivo. The outcome of this study provides an experimental basis for the treatment of human nasopharyngeal carcinoma by viral gene therapy.

[TAp63gamma-induced apoptosis mediated by apoptosis inducing factor in human esophageal squamous carcinoma EC9706 cells].

OBJECTIVE: To study the molecular mechanism of TAp63gamma-induced cell apoptosis. METHODS: Transcription and protein expression of apoptosis inducing factor and p63 were investigated by immunohistochemistry and RT-PCR in human esophageal squamous carcinoma cell line EC9706 respectively. Twenty-four hours after transfection with pcDNA3.1-TAp63gamma, the apoptosis and translocation of apoptosis inducing factor in EC9706 cells were studied by flow cytometry, laser confocal microscopy and mitochondrial/cytosol/nuclear extraction analysis respectively. Down-regulation of apoptosis inducing factor protein was achieved by RNAi and pretreatment with caspase inhibitor zVAD.fmk of EC9706 cells. RESULTS: Presence of protein expressions of apoptosis inducing factor and absence of TAp63gamma was observed in the cytoplasm of untransfected cells. RT-PCR verified the subtype of p63 in EC9706 cells was DeltaNp63. After 24 hours of transfection, both nuclear and cytoplasmic expression of apoptosis inducing factor protein were observed in cells transfected with TAp63gamma and p53 expression vectors, but not in cells transfected with control vector. Cell apoptosis rates were 1.37%, 13.64%, 4.52%, 4.03% and 1.91% in the pcDNA3.1 transfection group, pcDNA3.1-TAp63gamma transfection group, apoptosis inducing factor siRNA and pcDNA3.1-TAp63gamma transfection group, zVAD.fmk treatment group, and the group receiving apoptosis inducing factor siRNA, plus zVAD.fmk treatment and pcDNA3.1-TAp63gamma transfection, respectively. CONCLUSIONS: Apoptosis inducing factor of EC9706 cells is released from mitochondria into both the cytoplasm and nucleus during TAp63gamma induced apoptosis. Down-regulation of apoptosis inducing factor inhibits TAp63gamma-induced apoptosis. Overall, TAp63gamma-induced apoptosis is dependent on the expression of apoptosis inducing factor and caspase.

The actin gene promoter-driven bar as a dominant selectable marker for nuclear transformation of Dunaliella salina.

A 5'-flanking region of an actin gene from the green unicellular alga Dunaliella salina (D. salina) was cloned using a genome-walking method by PCR and its structural features were characterized. Two repetitive sequences found, over 75 bp in length each, were located at position -573 and -424 bp,respectively, relative to the AUG codon. The actin gene promoter region of D. salina displayed a consensus sequence of GCTC (G/C) AAGGC, a CCAAT motif and two TATA-like motifs that did not have a canonical sequence of a TATA box. The 5' flanking region of the actin gene was exploited to direct expression of the bialaphos resistance gene (bar) from Streptomyces hygroscopicus as a dominant marker in the nuclear transformation of D. salina. Direct selection of bar resistant transformants was achieved by allowing a 24 h period of recovery of cells transformed by biolistic procedure, followed by growth of the cells for one week under standard condition prior to harvesting and plating on the solid medium containing 0.5 microg/mL of phosphinothricin (PPT). Five colonies picked from the plate were analyzed, of which the integration of the bar gene was demonstrated in the nuclear genome. Southern blotting revealed that only one of five transformants contained a single copy of the bar gene whereas others contained multiple copies,suggesting that nuclear transformation of D. salina mainly occurred through illegitimate recombination events,resulting in ectopic integration of the introduced DNA. The integration patterns of the foreign DNA in this experiment appeared not to influence the bar gene expression in the transformants containing single or multiple inserts. The bar gene expression in the five transformants was verified by RT-PCR, confirming transcription of the chimeric DNA. These transformants were maintained on agar plates in the absence of PPT for more than seven months and retained resistance to the herbicide at 1 microg/mL. This work demonstrates that the actin gene promoter-driven expression of the bar gene may be used as a dominant selectable marker for nuclear transformation of D. salina.

[Cloning and functional analyses of promoters of two carbonic anhydrase genes from Dunaliella salina].

The cloning vectors pMD-DCA1 and pMD-CA containing the promoters of duplicated carbonic anhydrase 1 (DCA1) and carbonic anhydrase (CA) genes, respectively, from Dunaliella salina, and expression vector pDM307 containing bar-NOS polyA fragment were digested with EcoR I. The bar-NOS polyA fragment was fused, respectively, to the fragments of the vectors pMD-DCA1 and pMD-CA to form transgenic D. salina expression vectors pMDDC-B and pMDC-B. The micro-shots were prepared by coating two constructs (pMDDC-B and pMDC-B) with gold particle. Each sample was bombarded once, twice, and thrice, respectively, with micro-projectile gun at a rupture pressure of 690 kPa in helium gas. The screening culture of the bombarded alga cells was performed in PKS liquid and solid medium containing 3 mg/L phosphinothricin (PPT) to develop the transformed cells of D. salina. Analyses of the transformed cells were carried out through PCR, Southern blotting, and Northern blotting. The results of screening culture showed that the expression of the external bar gene of vectors pMDDC-B and pMDC-B was stable and transient, respectively, in the transformed D. salina cells. In the meantime, the transformed efficiency of particle bombardment twice was higher than that of once or thrice particle bombardment at a rupture pressure of 690 kPa in helium gas. PCR and Southern blotting analyses indicated that the external bar gene was integrated into the genome of the cells. Northern analysis indicated that expression efficiency of the bar gene driven by DCA1 promoter was regulated by the gradient concentration of sodium chloride, and the positive blotting signal intensity of the bar mRNA was highest in the medium containing 2 mol/L of sodium chloride. The findings of the present study suggest that promoter of the DCA1 gene may be an inducible promoter following a hyperosmotic shock with high activity and safety in the research of transgenic D. salina. The tandem GT sequences of the promoter region of DCA1 and CA genes may be related to the molecular mechanisms of the extreme halo-toleration of the unicellular green alga, D. salina.

[Cloning and characterization of Hsp70a cDNA fragment of Dunaliella salina].

The present study is to obtain heat shock protein 70a cDNA fragment from Dunaliella salina. Two pairs of degenerate primers were designed according to conserved motifs of DIDLGTT,DQGNRTTP,PAYFNDS and ATKDAG of the homologous amino acid sequences and used to amplify hsp70a cDNA fragment from heat-shock-treated Dunaliella salina by nest PCR technique. The resulting PCR products were inserted into T-vector then transformed into JM109. Ten colonies were selected to determine their sequences. Homologous analysis of the deduced amino acid sequences were performed by BLAST and subsequently compared with GenBank data. Three of ten nucleotide sequences were obtained,of which there was 372 bp coding 126 amino acids. The sequences shared high homology with hsp70a,with identity 96% to Chlamydomonas reinhardtii, 94% to Petunia, 93% to Pisumsativum, 92% to tomato, 92% to human,90% to Drosophila and 89% to yeast respectively. It can be concluded that the cloned sequence is putatively hsp70a cDNA fragment from Dunaliella salina.