Jin-Long Yu

Studies have found that long noncoding RNA HEIH (lncRNA-HEIH) is upregulated and facilitates hepatocellular carcinoma tumor growth. However, its clinical significances, roles, and action mechanism in colorectal cancer (CRC) remains unidentified. lncRNA-HEIH expression in CRC tissues and cell lines was measured by quantitative real-time polymerase chain reaction. Cell CountingKit-8, ethynyl deoxyuridine incorporation assay, terminal deoxynucleotidyl transferase dUTP nick end labeling staining, and nude mice xenografts assays were performed to investigate the roles of lncRNA-HEIH. RNA pull-down, RNA immunoprecipitation, chromatin immunoprecipitation, and luciferase reporter assays were performed to investigate the action mechanisms of lncRNA-HEIH. In this study, we found that lncRNA-HEIH is significantly increased in CRC tissues and cell lines. lncRNA-HEIH expression is positively associated with tumor size, invasion depth, and poor prognosis of CRC patients. Enhanced expression of lncRNA-HEIH promotes CRC cell proliferation and decreases apoptosis in vitro, and promotes CRC tumor growth in vivo. Whereas knockdown of lncRNA-HEIH inhibits CRC cell proliferation and induces apoptosis in vitro, and suppresses CRC tumor growth in vivo. Mechanistically, lncRNA-HEIH physically binds to miR-939. The interaction between lncRNA-HEIH and miR-939 damages the binding between miR-939 and nuclear factor κB (NF-κB), increases the binding of NF-κB to Bcl-xL promoter, and promotes the transcription and expression of Bcl-xL. Moreover, Bcl-xL expression is positively associatedwith lncRNA-HEIH in CRC tissues. Blocking the interaction between lncRNA-HEIH and miR-939 abolishes the effects of lncRNA-HEIH on CRC tumorigenesis. This study demonstrated that lncRNA-HEIH promotes CRC tumorigenesis through counteracting miR-939‒mediated transcriptional repression of Bcl-xL, and suggested that lncRNA-HEIH may serve as a prognostic biomarker and therapeutic target for CRC.

Previous studies used to enumerate circulating tumor cells to predict prognosis and therapeutic effect of colorectal cancer. However, increasing studies have shown that only circulating tumor cells enumeration was not enough to reflect the heterogeneous condition of tumor. In this study, we classified different metastatic-potential circulating tumor cells from colorectal cancer patients and measured FAM172A expression in circulating tumor cells to improve accuracy of clinical diagnosis and treatment of colorectal cancer. Blood samples were collected from 45 primary colorectal cancer patients. Circulating tumor cells were enriched by blood filtration using isolation by size of epithelial tumor cells, and in situ hybridization with RNA method was used to identify and discriminate subgroups of circulating tumor cells. Afterwards, FAM172A expression in individual circulating tumor cells was measured. Three circulating tumor cell subgroups (epithelial/biophenotypic/mesenchymal circulating tumor cells) were identified using epithelial–mesenchymal transition markers. In our research, mesenchymal circulating tumor cells significantly increased along with tumor progression, development of distant metastasis, and vascular invasion. Furthermore, FAM172A expression rate in mesenchymal circulating tumor cells was significantly higher than that in epithelial circulating tumor cells, which suggested that FAM172A may correlate with malignant degree of tumor. This hypothesis was further verified by FAM172A expression in mesenchymal circulating tumor cells, which was strictly related to tumor aggressiveness factors. Mesenchymal circulating tumor cells and FAM172A detection may predict highrisk stage II colorectal cancer. Our research proved that circulating tumor cells were feasible surrogate samples to detect gene expression and could serve as a predictive biomarker for tumor evaluation.

Colorectal cancer (CRC) is one of the most common cancers all over the world. It is essential to search for more effective diagnostic and therapeutic methods for CRC. Abnormal nicotinamide adenine dinucleotide (NAD) metabolism has been considered as a characteristic of cancer cells. In this study, nicotinamide mononucleotide adenylyl transferases (NMNATs) as well as p53-mediated cancer signaling pathways were investigated in patients with colorectal cancer. The CRC tissues and adjacent normal tissues were obtained from 95 untreated colorectal cancer patients and were stained for expression of nicotinamide mononucleotide adenylyl transferase 2 (NMNAT2) and p53. The survival rate was analyzed by the Kaplan-Meier method and the log-rank test. The multivariate Cox proportional hazard regression analysis was conducted as well. Our data demonstrated that expression of NMNAT2 and p53 was significantly higher in CRC tissues, while NMNAT2 expression is in correlation with the invasive depth of tumors and TNM stage. Significant positive correlation was found between the expression of NMNAT2 and the expression of p53. However, NMNAT2 expression was not a statistically significant prognostic factor for overall survival. In conclusion, our results indicated that NMNAT2 might participate in tumorigenesis of CRC in a p53-dependent manner and NMNAT2 expression might be a potential therapeutic target for CRC.

The present study was designed to elucidate the regulatory role of a novel protein FAM172A in carcinogenesis of colorectal carcinoma (CRC). Investigation of clinical samples using Western blotting showed that expression of FAM172A is significantly lower in cancerous tissues than in adjacent tissues. Furthermore, we constructed in vitro model for continuous overexpression and silencing of FAM172A with a retroviral vector system. FAM172A suppressed the proliferative and invasive potentials of LOVO cells as shown in MTT test, transwell migration assay, wound healing assay, 3D-culture morphologic study, and xenograft experiment. RT-PCR and Western blotting showed that FAM172A overexpression inhibited expressions of Cyclin D1, CDK2, MMP-2, MMP-9, PERK, elF2α, ATF6, XBP1, and GRP78, while FAM172A silencing induced their expressions. FAM172A might regulate ERS through PERK-elF2α, ATF6-XBP1-GRP78 signal pathway. The results implicated that FAM172A functioned as a tumor suppressor in colorectal carcinoma.

To investigate the clinical value of three-dimensional (3D) high-definition (HD) laparoscope in laparoscopic radical resection of gastric cancer. From January to December, 2013, 40 patients underwent radical resection of gastric cancer with 3D HD laparoscopy (3D group) and another 40 patients received 2D HD laparoscopy (2D group). The duration of surgery, intra-operative blood loss, learning curve, and costs during hospitalization were compared between the two groups. The average operation duration of 3D group was 2.8=0.6 h, significantly shorter that in the 2D group (3.2=0.8 h, P0.05). The mean hospitalization cost was 75 000=16 000 RMB Yuan in 3D group, similar to significantly lower than that of 71 000=13 000 RMB Yuan in 2D group (P>0.05). 3D HD laparoscopy can provide three-dimensional vision and better sense of depth to facilitate precise operation and shorten the operation time. The high-definition 3D vision also allows surgeons to quickly improve surgical skills and shorten the learning curve.

目的: 探讨重组腺病毒介导KDR-CDglyTK系统杀伤胃癌SCG7901细胞时细胞缝隙连接与旁观者效应的关系. 方法: 感染复数(multiplicity of infection, MOI) = 100时, 将携带融合基因重组腺病毒体外感染SCG7901、HeLa细胞, 检测细胞的感染效率以及转基因肿瘤细胞在mRNA水平上融合基因的表达; 用荧光漂白恢复技术(fluorescence recovery after photobleaching, FRAP)检测SCG7901、HeLa细胞以及芹黄素作用上述两种细胞的细胞间通讯功能. 将已转染细胞和未转染细胞分别按10%:90%和5%:95%两种比例混合, 用含或不含芹黄素的培养基, 培养24 h后, 在不同组中分别加入GCV、5-FC两者的混合液, 72 h后用MTT法检测细胞存活率. 结果: 受感染的SCG7901和HeLa细胞中均有绿色荧光蛋白的表达. 图像中观察到在芹黄素作用下SCG7901细胞淬灭后荧光强度明显降低, 随后随着时间的推移, 被淬灭细胞的荧光强度逐渐恢复, 在相同时间内其恢复强度较未应用上调剂的SCG7901细胞要强; 而在芹黄素作用下的HeLa细胞被淬灭后荧光强度明显降低, 随时间的推移荧光强度无明显恢复, 在上调剂芹黄素作用下的SCG7901与HeLa细胞间的荧光恢复率有差异. 同时, 观察到双自杀基因系统在转基因细胞比例分别占5%、10%时, SCG7901细胞在空白组、前药组、芹黄素组、前药+芹黄素组间细胞生存率有差异(F = 144.42, P = 0.000)、(F = 407.83, P = 0.000), 而HeLa细胞在各组间的细胞生存率无统计学意义(F = 0.386, P = 0.765)、(F = 0.895, P = 0.472). 结论: FRAP技术证实SCG7901细胞间通讯功能与缝隙连接有一定关系, 而HeLa细胞不存在细胞间通讯功能. 双自杀基因系统治疗SCG7901细胞时存在旁观者效应而且上调剂可以扩大其旁杀效应; 但HeLa细胞不存在旁观者效应. 双自杀基因系统治疗胃癌细胞时旁观者效应与细胞间缝隙连接有关.

To study the selective killing effect of adenovirus (Ad)-mediated double suicide gene system driven by the KDR promoter (KDR-CDglyTK) on human colon adneocarcinoma SW480 cells. KDR-expressing SW480 cells and LS174T cells that did not express KDR were infected by KDR-CDglyTK, and the infection efficiency and the expression of CDglyTK in the cells were detected by RT-PCR. The infected cells were treated with the prodrugs 5-FC and GCV at different concentrations, and the cell-killing effects and bystander effects were evaluated by MTT method. DNA content and the cell cycle changes in SW480 cells were detected by flow cytometry. The expression of green fluorescent protein (GFP) was observed in 95% of the infected SW480 and LS174T cells with a multiplicity of infection (MOI) of 100. RT- PCR demonstrated that the product of CD/TK gene existed in SW480 cells infected by Ad- KDR- CD/TK, but not in infected LS174 cells. The infected SW480 cells exhibited high sensitivity to the prodrugs, but the infected LS174T cells did not (P<0.01). Bystander effects of the double suicide gene system were observed in the coculture of the infected and non-infected SW480 cells. At the MOI of 100, treatment of the infected cells with the prodrugs resulted in increased cell percentage in G(0)-G(1) phase and decreased percentage in S phase and the prodrug-treated cells showed an apoptotic peak in flow cytometry. CDglyTK fusion gene system driven by the KDR promoter selectively kills and induces the apoptosis of the KDR-CDglyTK SW480 cells.

To study the inhibitory effect of adenovirus-mediated fusion gene system driven by KDR promoter on the proliferation of human gastric adneocarcinoma SCG7901 cells and observe the bystander effect in vitro. SCG7901, ECV304 and HepG2 cells were infected with Ad-KDR-CDglyTK and Ad-CMV-CDglyTK at a multiplicity of infection (MOI) of 100, and the infection efficiency and the mRNA expressions of the transferred fusion gene were investigated. GCV and/or 5-FC at different concentrations were added into the culture medium of the infected cells to observe the targeted antitumor effect and bystander effect of CDglyTK suicide gene driven by KDR promoter. With the MOI of the adenovirus of 100, the fluorescence emitted by green fluorescent protein (GFP) was observed in 95% of the infected SCG7901, ECV304 and HepG2 cells. All the cells infected by Ad-CMV-CDglyTK and SCG7901 and ECV304 cells infected by Ad-KDR-CDglyTK were highly sensitive to the prodrugs. In comparison, HepG2 cells infected with Ad-KDR-CDglyTK did not show much sensitivity to the two prodrugs. Following treatment with the prodrugs at the same concentration, the infected SCG7901 and ECV304 cells exhibited gradually lowered survival rates as the culture time was prolonged, whereas the transgenic HepG2 cells showed no such time-dependent changes. When the non-infected cells were cocultured with the transgenic cells, the bystander effect of CDglyTK gene was observed, which increased with the ratio of the transgenic cells. In these mixed cell culture systems, GCV and 5-FC showed obvious synergetic effect in suppressing the cell survival. The CDglyTK fusion gene system driven by KDR promoter can inhibit the proliferation of SCG7901 and ECV304 cells with obvious bystander effect in vitro. The combination of the prodrugs produces obvious synergetic effect against the cell survival.

To study the selective killing effects of adenovirus (Ad)-mediated double suicide gene system driven by KDR promoter (KDR-CdglyTK) on the human hepatic carcinoma cells and human umbilical vein endothelial cells (HUVECs). KDR-expressing BEL-7402 and HUVECs and HepG2 cells that did not express KDR were infected by KDR-CdglyTK, and the infection efficiency and the expression of CdglyTK in the cells was detected by RT-PCR. The infected cells were treated with the the prodrugs 5-FC and GCV at different concentrations, and the cell-killing effects and bystander effects were evaluated by MTT method. At the multiplicity of infection (MOI) of 100, the recombinant AdKDR-CDglyTK showed similar infection efficiency in the 3 cell lines. RT-PCR demonstrated CDglyTK expression in the recombinant adenovirus and the 3 infected cell lines. BEL-7402 and HUVECs infected by the KDR-CdglyTK, but not the HepG2 cells, were highly sensitive to the prodrugs (P<0.001). Bystander effects of the double suicide gene system were observed in the coculture of the infected and non-infected BEL-7402 and HUVECs. The double suicide gene system driven by KDR promoter has specific killing effect on KDR-expressing hepatocellular carcinoma cells and HUVECs.

To investigate the effect of 5-aminolevulinic acid (ALA)-mediated photodynamic therapy (PDT) on human gastric cancer xenografts in vivo and to explore its potential tumoricidal mechanism. Cultured MGC-803 human gastric cancer cells were injected below the skins of the nude mice to develop the tumor model. The tumor-bearing nude mice were examined under the Leica LT-9 MACIMSYSPULS to detect the fluorescence. The tumor volume of day 1, 3, 7, 14, 21 after treatment were measured, and its histological changes were also studied. The tissues of the tumors in nude mice of the control group, light group, 5-ALA group and PDT group were examined with the electron microscope and apoptosis was detected by TUNEL assay. The tumor model was successfully developed. The tumor in the nude mice emitted the red fluorescence under the Leica LT-9 MACIMSYSPULS. The tumor volumes were (0.189+/-0.010) cm(3), (0.183+/-0.011) cm(3), (0.185+/-0.019)cm(3), (0.182+/-0.015)cm(3) for the control group, light group, 5-ALA group, PDT group, respectively at day 1 after treatment, while at day 3, (0.294+/-0.010) cm(3), (0.280+/-0.013) cm(3), (0.278+/-0.016) cm(3), (0.183+/-0.014) cm(3); at day 7, (0.409+/-0.016) cm(3), (0.411+/-0.009) cm(3), (0.407+/-0.015) cm(3), (0.221+/-0.008) cm(3); at day 14, (0.970+/-0.055) cm(3), (0.976+/-0.054) cm(3), (0.981+/-0.032)cm(3), (0.318+/-0.005) cm(3); at day 21, (1.495+/-0.059) cm(3), (1.513+/-0.057) cm(3), (1.524+/-0.063) cm(3), (0.446+/-0.042) cm(3) (F=1003.086, P=0.000). The histology demonstrated that most tumor blood vessels were congested and necrosis developed after PDT while not in the control group, light group and 5-ALA group. Necrosis and apoptosis were observed in the cells of the tumors of the PDT group examined by TUNEL and electron microscope while not in the cells of the tumors of the other groups. 5-aminolevulinic acid-mediated photodynamic therapy (PDT) can induce injury to human gastric cancer xenografts and inhibit the tumor growth while light only and 5-ALA only can not. 5-aminolevulinic acid-mediated photodynamic therapy (ALA- PDT) appears to be a promising therapy for human gastric cancer, whose mechanism involves in the destruction of the tumors partly by apoptosis other than necrosis.