Circular RNA hsa_circ_0064559 affects tumor cell growth and progression of colorectal cancer.

BACKGROUND: Colorectal cancer (CRC) is the second leading cause of cancer-related deaths globally. It is essential to identify new CRC-associated therapeutic targets and diagnostic biomarkers. Previous studies have demonstrated that a series of circular RNAs (circRNAs) play a crucial role in CRC pathogenesis. This study assessed the potential of hsa_circ_0064559 in tumor cell growth and progression of CRC. METHODS: Six pairs of matched CRC and normal colorectal tissue samples were sequenced using the Affymetrix Clariom D array. Using RNA interference, the expression of thirteen circRNAs was knocked down in CRC cells. The proliferation of CRC cell lines (RKO and SW620 cells) was detected using 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide (MTT) assay. Apoptosis and cell cycle were determined by flow-cytometric analysis. An in vivo study uses nude mice to establish a CRC mouse model. The differentially expressed genes were analyzed using Affymetrix primeview human GeneChip array and verified by polymerase chain reaction. RESULTS: Affymetrix Clariom D array analysis revealed that thirteen circRNAs were upregulated in CRC. The proliferation of CRC cell lines was decreased, while the proportion of apoptotic and G1 phase cells was higher after hsa_circ_0064559 knockdown. In vivo xenograft nude mice model revealed that the volume and weight of the tumor were reduced by hsa_circ_0064559 knockdown. In Affymetrix primeview human GeneChip array, we found six upregulated genes (STAT1, ATF2, TNFRSF10B, TGFBR2, BAX, and SQSTM1) and two downregulated genes (SLC4A7 and CD274) related to apoptosis and proliferation of colorectal cancer cells after hsa_circ_0064559 knockdown. CONCLUSIONS: The hsa_circ_0064559 knockdown could inhibit the proliferation, promote apoptosis in CRC cell lines in vitro, and inhibit the development of CRC tumors in vivo. The mechanism may be related to activating a wide range of signaling pathways. The hsa_circ_0064559 may be a potential biomarker for early diagnosis or prognosis of CRC and a novel drug target for CRC therapy.

The clinical utility of image-guided iodine-125 seed in patients with unresectable pancreatic cancer.

In the present study, we investigated the clinical effects of image-guided iodine-125 ((125)I) seed on unresectable pancreatic cancer. Twenty-five patients with unresectable pancreatic cancer were enrolled in this study, including 13 patients with seed implantation and 12 patients as control. The survival status, clinical benefits, objective curative effects, and relevant tumor markers were analyzed to assess the feasibility and safety of interstitial (125)I seed implantation. We found that the clinical benefit rate of the seed implantation group is 92.3 % (12/13), compared with 41.7 % (5/12) in the control, and the difference was statistically significant (p < 0.01). Compared with control, patients with seed implantation had significantly shorter operative time, less bleeding, higher albumin, shorter periods to bowel movement, and normal diet as well as lower risk of complications (p < 0.001). The differences of objective curative effects adverse effects, complications, and median survival between these two groups were not significant statistically (p > 0.05). In conclusion, (125)I seed implantation provides a safe and effective method to inhibit the tumor development, relieve pain, and improve quality of life for unresectable pancreatic cancer. These findings need to be validated by conducting further studies with larger cohorts.

BAG3 regulates cell proliferation, migration, and invasion in human colorectal cancer.

Bcl2-associated athanogene 3 (BAG3) has been reported to be elevated in various tumors. However, it is unclear whether BAG3 has a functional role in the initiation and progression of colorectal cancer (CRC). Here, we collected CRC samples and cell lines to validate the pathway by using gene and protein assays. RT-PCR showed that the expression of BAG3 mRNA in CRC tissues was obviously higher than that in non-tumor tissues (p < 0.001). Immunohistochemical analysis showed that immunoreactivity of BAG3 was found in most CRC tissues and strongly correlated with TNM stage (p = 0.001), differentiation (p = 0.003), and metastasis (p = 0.010). Low expression of BAG3 in HCT-8 significantly reduced cellular proliferation, migration, and invasion. The analysis of in vitro cell showed that HCT-8 cells were exposed to si-BAG3, and its growth was inhibited depending on modulation of cell cycle G1/S checkpoints and cell cycle regulators, involving cyclin D1, cyclin A2, and cyclin B1. Furthermore, suppression of the epithelial-mesenchymal transition (EMT) by si-BAG3 is linked to the decreased expression of E-cadherin and the increased expression of N-cadherin, vimentin, and MMP9. In conclusion, in the present study, we demonstrated that BAG3 overexpression plays a critical role in cell proliferation, migration, and invasion of colorectal cancer. Our data suggests targeted inhibition of BAG3 may be useful for patients with CRC.

Robotic versus laparoscopic low anterior resection for rectal cancer: a meta-analysis.

BACKGROUND: The objective of this meta-analysis was to compare the clinical and oncologic outcomes of robotic low anterior resection (R-LAR) with conventional laparoscopic low anterior resection (L-LAR). METHODS: A search in the MEDLINE, Embase, and Ovid databases was performed for studies published before July 2014 that compared the clinical and oncologic outcomes of R-LAR and L-LAR. The methodological quality of the selected studies was assessed. Depending on statistical heterogeneity, a fixed or random effects model was used for the meta-analysis. The clinical and oncologic outcomes evaluated included operative time, estimated blood loss, length of hospital stay, rate of conversion to open surgery, post-operative complications, circumferential margin status, and number of lymph nodes collected. RESULTS: Eight studies, including 324 R-LAR cases and 268 conventional L-LAR cases, were analyzed. The meta-analysis showed that R-LAR was associated with a shorter hospital stay (mean difference (MD) = -1.03; 95% confidence interval (CI) = -1.78, -0.28; P = 0.007), lower conversion rate (odds ratio (OR) = 0.08; 95% CI = 0.02, 0.31; P = 0.0002), lower rate of circumferential margin involvement (OR = 0.5; 95% CI = 0.25, 1.01; P = 0.05), and lower overall complication rate (MD = 0.65; 95% CI = 0.43, 0.99; P = 0.04) compared with L-LAR. There was no difference in operative time (MD = 28.4; 95% CI = -3.48, 60.27; P = 0.08), the number of lymph nodes removed (MD = -0.63; 95% CI = -0.78, 2.05; P = 0.38), and days to return of bowel function (MD = -0.15; 95% CI = -0.37, 0.06; P = 0.17). CONCLUSIONS: R-LAR was shown to be associated with a shorter hospital stay, lower conversion rate, lower rate of circumferential margin involvement, and lower overall complication rate compared with L-LAR. There were no differences in operative time, the number of lymph nodes removed, and days to return of bowel function.

Cell surface nucleolin interacts with CXCR4 receptor via the 212 c-terminal portion.

Previously, we reported that CXCR4 receptor interacted with cell surface nucleolin, and the synergy of CXCR4 and nucleolin plays an essential role in malignant transformation. Here, we continued to conduct a structure-function analysis of nucleolin to identify which portion can efficaciously bind to CXCR4. In the present study, the expression of CXCR4 and nucleolin in 100 cases of papillary thyroid cancer (PTC) samples was investigated through immunohistochemistry (IHC). Subsequently, using nucleolin mutants and pull-down assay, we investigated precise interactions between CXCR4 and nucleolin in HEK-293 cells. A previous study demonstrated CXCR4 and nucleolin co-expressed in cell lines, and the present study further identified that CXCR4 and nucleolin co-expressed in PTC tissues, instead of normal tissues. The nucleolin mutant analysis revealed that nucleolin can efficaciously bind CXCR4 to activate CXCR4 signaling by 212 C-terminal domain. Conversely, N-terminal, RBD and GAR mutants of nucleolin showed no sign of activation of CXCR4 signaling, and differences were statistically insignificant (p > 0.05). In conclusion, these results suggested nucleolin is essential to activate CXCR4 signaling via 212 C-terminal domain, which is required for cell growth, migration, and invasiveness. Furthermore, nucleolin may interact with more G protein-coupled receptors, at least chemokine receptor. Our study will lay a new foundation for cancer therapy by antagonizing nucleolin and CXCR4.

P21-activated kinase 1 and 4 were associated with colorectal cancer metastasis and infiltration.

BACKGROUND: P21-activated kinases (PAKs) are small guanosine triphosphate effectors that play critical roles in many fundamental cellular functions, including cytoskeletal reorganization and cell motility. PAKs are widely expressed in a variety of tissues and are often overexpressed in multiple cancer types. The aim of this study was to investigate the relationship between PAK1 and PAK4 and clinicopathologic features of colorectal cancer. METHODS: PAK1 and PAK4 expression in colorectal cancer patients were investigated via TaqMan real-time polymerase chain reaction and immunohistochemistry and clinical analysis. RESULTS: The relative expression levels of PAK1 and PAK4 gene in colorectal carcinoma tissues were significantly higher than those in normal tissues (P < 0.01). PAK4 expression was higher than PAK1 in the same cancer tissue. The expression of PAK1 and PAK4 increased gradually with the clinical stages in carcinoma tissues (P < 0.01). PAK1 expression was higher in lymph node positive patients, and PAK4 expression was higher in infiltration into serous layer patients (P < 0.05). PAK1 overexpression group has a higher recurrence/metastasis rate compared with that of the PAK1 low expression group. Follow-up analysis showed that the median progression-free survival time of the PAK1 high expression group was significantly shorter than that of the PAK1 low expression group. CONCLUSIONS: PAK1 and PAK4 expression were associated with colorectal cancer metastasis and infiltration, PAK1 high expression may indicate poor prognosis of colorectal cancer.

[Silencing HMGB1 expression by lentivirus-mediated small interfering RNA (siRNA) inhibits the proliferation and invasion of colorectal cancer LoVo cells in vitro and in vivo].

OBJECTIVE: To inquire into the influence of silencing HMGB1 expression by small interfering RNA (siRNA) on cell growth, proliferation, invasion and metastasis of colorectal cancer LoVo cells both in vitro and in vivo. METHODS: Lentivirus-mediated HMGB1 siRNA was transfected into LoVo cells to silence the HMGB1 expression. The HMGB1 mRNA and protein expression after siRNA transfection was detected by RT-PCR and Western blot. MTT assay was used to observe the cell proliferation and to draw a growth curve. Cell cycle was measured by flow cytometry. The ability of invasion and speed of cell migration were evaluated by transwell chamber invasion and cell scratch assay. The influence of HMGB1 silencing on the proliferation of LoVo cells in vivo was observed in LoVo tumor-bearing nude mice. RESULTS: Lentivirus-mediated siRNA was successfully transfected into colorectal cancer cell line LoVo. The expression of HMGB1 mRNA and protein in the HMGB1-siRNA group were 0.24±0.04 and 0.21±0.03, respectively. Compared with the HMGB1-siRNA-Neg group (0.82±0.13, 1.15±0.18) and control group (0.93±0.15, 1.21±0.20), the difference was significant (P<0.05). MTT assay showed that the cell proliferation in the HMGB1-siRNA group was significantly inhibited when compared with that in the HMGB1-siRNA-Neg group and control group (P<0.05). Flow cytometry showed that the proliferation index (PI) of HMGB1-siRNA group was 38.27±1.32, significantly lower than 54.66±1.74 in the HMGB1-siRNA-Neg group and 57.43±1.29 in the control group (P<0.05). The transwell assay showed that the number of penetrated cells in the HMGB1-siRNA group was 14.0±3.5, significantly lower than 51.0±6.7 in the HMGB1-siRNA-Neg group and 68.0±5.3 in the control group (P<0.05). Similarly, the scrape wound recovered significantly slower in the HMGB1-siRNA group (83.61±23.21) µm than that in the other two groups (202.86±46.46) µm and (214.58±57.38) µm(P<0.05). The nude mouse xenograft tumor experiment showed that the final tumor volume was (521±34) mm3 in the HMGB1-siRNA group, significantly smaller than that in the HMGB1-siRNA-Neg group of (763±46) mm3 and control group of (802±51) mm3 (P<0.05). CONCLUSIONS: Lentivirus-mediated HMGBl-siRNA can effectively inhibit the HMGB1 expression in colorectal cancer LoVo cells both in vitro and in vivo. HMGB1 gene silencing can slow the growth of colorectal cancer cells, extend the cell proliferation cycle, decrease their invasion and migration, and significantly inhibit the growth of xenograft tumor in nude mice.

The clinical implications of Crk-like adaptor protein expression in papillary thyroid microcarcinoma.

Papillary thyroid microcarcinoma (PMC) is the most common subtype of thyroid carcinomas with satisfactory prognosis. Crk-like (CrkL) adaptor protein was identified in the development of many carcinomas. However, the clinical implications of CrkL protein in PMC were still unknown. Here, we conducted immunohistochemistry to test and analyze CrkL expression in papillary thyroid carcinoma (PTC) (50 cases), PMC (50 cases), and nodular goiter (50 cases), and then western blot further identified the expression of CrkL proteins. In our present study, the positive rate and the mean optical density (MOD) value of CrkL expression in PTC and PMC tissues were statistically significantly different, compared with nodular goiter (p = 0.021, 0.037) and normal thyroid tissues (p = 0.003, 0.009), respectively. In addition, CrkL expression was not associated with age, gender, and tumor number. Conversely, significant differences between CrkL expression and metastasis (p < 0.01) and violation of capsule (p < 0.01) were observed. Notably, western blot indeed identified that the metastasis group of either PTC or PMC tissues had about twofold increased expression of CrkL compared with their non-metastasis groups (p < 0.05). In conclusion, CrkL is highly expressed in papillary thyroid carcinoma and papillary thyroid microcarcinoma and closely correlated to metastasis. Therefore, it is essential to carry out neck lymph node clearance in patients with papillary thyroid microcarcinoma.

The correlation of bone morphogenetic protein 2 with poor prognosis in glioma patients.

Glioma is the most common type of human intracranial cancers and has poor prognosis. Bone morphogenetic protein 2 (BMP2) plays important roles in cancer cell signalings (Vecht et al. Oncologist 19:751-9, 2014). Here, we aimed to investigate the correlation of BMP2 with patient prognosis as well as pathological indicators. Immunohistochemistry was used to test BMP2 proteins in 45 gliomas of distinct malignancy grade, and Kaplan-Meier survival analysis was performed to assess prognostic significance. BMP2 protein was also detected in cell lines by Western blot. We observed that BMP2 protein was stained in 44.4% (20 out of 45) of all glioma tissues, including 32.1% of low-grade (I + II) gliomas and 52.9% of high-grade (III + IV) gliomas. Grade IV gliomas potently expressed BMP2 proteins. Western blot showed BMP2 protein expressed in cell lines NHA, A172, T98G, U87, and U251. In addition, BMP2 expression was significantly associated with WHO grade (p = 0.024). According to log-rank test and Cox regression model, BMP2 can be suggested as an independent prognostic factor, apart from WHO grade. Taken together, BMP2 is differently highly expressed in different grades of gliomas and correlated to WHO grade. BMP2 also independently indicates poor prognosis in old glioma patients, which is indicative of an effectively therapeutic target.

Cell surface nucleolin is crucial in the activation of the CXCL12/CXCR4 signaling pathway.

Recently, CXCL12-CXCR4 has been focused on therapeutic strategies for papillary thyroid carcinoma (PTC) and other cancers. At the same time, cell surface nucleolin is also over-expressed in PTC and others. Interestingly, a few reports suggest that either CXCR4 or cell surface nucleolin is a co-receptor for HIV-1 entry into CD4+ T cells, which indicates that there is a relationship between CXCR4 and nucleolin. In this study, antibody and siRNA were used to identify effects of cell surface nucleolin and CXCR4 on cell signaling; soft-agar colony formation assay and Transwell assay were used to determine roles of nucleolin and CXCR4 in cell proliferation and migration. Importantly, co-immunoprecipitation was used to demonstrate the relationship between CXCR4 and nucleolin. Results showed CXCR4 and nucleolin were co-expressed in PTC cell line K1, B-CPAP, and TPC-1. Either cell surface nucleolin or CXCR4 was necessary to prompt extracellular signal-regulated kinase phosphorylation. When blocked, CXCR4 or nucleolin can significantly affect TPC-1 proliferation and migration (p < 0.01). Co-immunoprecipitation analysis identified that nucleolin can bind and interact with CXCR4 to activate CXCR4 signaling. This study suggests that nucleolin is crucial in the activation of CXCR4 signaling, which affects cell growth, migration, and invasiveness. Further, nucleolin may interact with other receptors. Our study also offers new ideas for cancer therapy.

Robotic versus laparoscopic right colectomy: a meta-analysis.

BACKGROUND: The objective of this meta-analysis was to compare the clinical safety and efficacy of robotic right colectomy (RRC) with conventional laparoscopic right colectomy (LRC). METHODS: A literature search was performed for comparative studies reporting perioperative outcomes of RRC and LRC. The methodological quality of the selected studies was assessed. Depending on statistical heterogeneity, the fixed effects model or the random effects model were used for the meta-analysis. Operative time, estimated blood loss, length of hospital stay, conversion rates to open surgery, postoperative complications, and related outcomes were evaluated. RESULTS: Seven studies, including 234 RRC cases and 415 conventional LRC cases, were analyzed. The meta-analysis showed that RRC had longer operative times (P < 0.00001), lower estimated blood losses (P = 0.0002), lower postoperative overall complications (P = 0.02), and significantly faster bowel function recovery (P < 0.00001). There were no differences in the length of hospital stay (P = 0.12), conversion rates to open surgery (P = 0.48), postoperative ileus (P = 0.08), anastomosis leakage (P = 0.28), and bleeding (P = 0.95). CONCLUSIONS: Compared to LRC, RRC was associated with reduced estimated blood losses, reduced postoperative complications, longer operative times, and a significantly faster recovery of bowel function. Other perioperative outcomes were equivalent.

[Inhibitory effect of silencing of HMGB1 gene expression on the invasive and metastatic abilities of MGC-803 gastric cancer cells].

OBJECTIVE: To investigate the effect of high mobility group box-1 (high mobility group box B 1, HMGB1) on the invasive and metastatic abilities of gastric cancer cell line MGC-803 and analyze the possible mechanisms. METHODS: HMGB1 gene targeting siRNA was designed and synthesized, and HMGB1 siRNA oligonucleotides were transfected into the MGC-803 cells with Lipofectamine 2000. The invasive and migratory abilities were detected by transwell assay and scratch assay. The Matrigel matrix glue adhesive ability of MGC-803 cells was evaluated by MTT assay. NF-κB activity was detected by electrophoretic mobility shift assay. The mRNA and protein levels of HMGB1 and MMP-9 were determined by RT-PCR and Western blot, respectively. RESULTS: The siRNA down-regulated the levels of HMGB1 mRNA and protein. Compared with that of the control group, the number of invasive (142.7 ± 3.4 /view vs. 303.5 ± 4.3/view) and migratory (293.7 ± 4.4/view vs. 445.5 ± 5.6/view) cells was significantly increased (P < 0.05) and the adhesive ability of MGC-803 cells to Matrigel was significantly elevated (33.4 ± 0.03% vs. 57.4 ± 4.2%, P < 0.05). In addition, silencing of HMGB1 gene significantly inhibited the activity of NF-κB and the relative expression folds of mRNA (0.2 ± 0.1 vs. 1.4 ± 0.4, P < 0.05)and protein (0.4 ± 0.1 vs. 2.3 ± 0.7, P < 0.05) of MMP-9. CONCLUSION: Silencing of HMGB1 can effectively inhibit the invasion and migration of gastric cancer cells and this effect of HMGB1 may be partly due to its regulation of NF-κB and MMP-9 expressions.

Effect of HMGB1 silencing on cell proliferation, invasion and apoptosis of MGC-803 gastric cancer cells.

High-mobility group box 1 (HMGB1) is a multifunctional protein with intranuclear and extracellular functions. Although HMGB1 is overexpressed in approximately 85% of gastric cancers, the role of HMGB1 in gastric cancer biology remains unclear. In this study, we investigate the effect of downregulation of HMGB1 on the biological behavior of gastric cancer cells. MGC-803 gastric cancer cells were transduced with HMGB1-specific RNAi lentiviral vectors. Real-time polymerase chain reaction and Western blot analysis of HMGB1 mRNA and protein, respectively, validated the silencing effects. HMGB1-specific silencing significantly decreased cell proliferation. The impact on proliferation was observed at the cell cycle level--the number of cells in the G0/G1 phase increased, whereas that in S and G2/M phases decreased. Cell cycle changes were accompanied by decreases in cyclin D1 expression. Furthermore, HMGB1 silencing sensitized cells to apoptosis that was induced by oxaliplatin and mediated by the caspase-3 pathway. Finally, silencing of HMGB1 expression significantly reduced cellular metastatic ability and MMP-9 expression in MGC-803 cells. In summary, HMGB1 not only plays an essential role in the proliferation and invasion of MGC-803 cells but also represents a potential target for the therapeutic intervention of gastric cancer.

Small interfering RNA-mediated downregulation of beta-catenin inhibits invasion and migration of colon cancer cells in vitro.

BACKGROUND: Abnormal regulation of Wnt/beta-catenin signaling and subsequently increased beta-catenin expression have been found to be involved in the proliferation and growth of colon cancer cells. Whether the down-regulation of beta-catenin in colon cancer may result in compromised invasion and migration in vitro still remains to be determined. MATERIAL/METHODS: A human colon cancer cell line (LoVo cells) was transfected with small interfering RNA (siRNA) targeting beta-catenin. RT-PCR, Western blot assay, flow cytometry, cell adhesion assay, scratch wound assay, and matrigel invasion assay were performed, and the correlation between cell invasion and migration and beta-catenin expressions was analyzed. RESULTS: siRNA-mediated down-regulation of beta-catenin elevated the E-cadherin expression but reduced the MMP-7 and CD44v6 expressions, which increased the adhesion between LoVo cells but decreased the adhesion of LoVo cells to fibronectin. Significant inhibition of cell invasion and migration was also observed following RNA interference with beta-catenin siRNA. CONCLUSIONS: siRNA-mediated downregulation of beta-catenin could be valuable for defining gene expression and functional programs downstream of oncogenic beta-catenin signals, which, in turn, may be helpful to isolate novel diagnostic markers, and for designing tumor-specific intervention at downstream targets of oncogenic beta-catenin.

[Correlation of VEGF and Ki67 expression with sensitivity to neoadjuvant chemoradiation in rectal adenocarcinoma].

OBJECTIVE: To investigate the correlation of expression of vascular endothelial growth factor (VEGF) and proliferating cell nuclear antigen (Ki67) with sensitivity to neoadjuvant chemoradiation in rectal adenocarcinoma. METHODS: Samples of pretreatment biopsies and the resected specimens after neoadjuvant therapy in 32 patients with rectal adenocarcinoma were collected, and the expression of Ki67 and VEGF were detected by immunohistochemistry using specific antibodies. The correlation of Ki67 and VEGF expression with clinicopathological factors were analyzed. RESULTS: The level of VEGF expression was significantly correlated with lymph node metastasis (P = 0.033), depth of tumor invasion (P = 0.007) and TNM stage (P = 0.016), but not with histological type, tumor size, age and gender of the patients (P > 0.05). However, VEGF expression was found to be negatively and significantly correlated with the sensitivity to neoadjuvant chemoradiation (P = 0.016), and a transient increase of VEGF expression was detected in the resected specimens after neoadjuvant therapy (P = 0.035). Ki67 labeling index (Ki67-LI) was found to be significantly correlated with lymph node metastasis (P = 0.028), but not with tumor size, age and gender of the patients (P > 0.05). It was also found that tumors with lower Ki67-LI expression were more sensitive to neoadjuvant therapy than that with higher expression of Ki67-LI (P = 0.032). In contrast with VEGF, the Ki67 expression level decreased after neoadjuvant therapy, but no statistical significance was found between pretreatment and posttreatment specimens (P > 0.05). CONCLUSION: The preliminary results of this study demonstrate that the expression of VEGF and Ki67 in pretreatment biopsy of rectal adenocarcinoma may be used as a biomarker to predict tumor response to neoadjuvant chemoradiation.

Identification of the differential expressive tumor associated genes in rectal cancers by cDNA microarray.

AIM: To identify tumor associated genes of rectal cancer and to probe the application possibility of gene expression profiles for the classification of tumors. METHODS: Rectal cancer tissues and their paired normal mucosa were obtained from patients undergoing surgical resection of rectal cancer. Total RNA was extracted using Trizol reagents. First strand cDNA synthesis was indirectly labeled with aminoallyl-dUTP and coupled with Cy3 or Cy5 dye NHS mono-functional ester. After normalization to total spots, the genes which background subtracted intensity did not exceed 2 SD above the mean blank were excluded. The data were then sorted to obtain genes differentially expressed by >or= 2 fold up or down in at least 5 of the 21 patients. RESULTS: In the 21 rectal cancer patients, 23 genes were up-regulated in at least 5 samples and 15 genes were down-regulated in at least 5 patients. Hierachical cluster analysis classified the patients into two groups according to the clinicopathological stage, with one group being all above stage II and one group all below stage II. CONCLUSION: The up-regulated genes and down-regulated genes may be molecular markers of rectal cancer. The expression profiles can be used for classification of rectal cancer.

MicroRNA­499 rs3746444 A/G polymorphism functions as a biomarker to predict recurrence following endoscopic submucosal dissection in primary early gastric cancer.

The aim of the present study was to investigate the molecular mechanism, including the potential regulatory and signaling pathways, of platelet­derived growth factor receptor ß (PDGFRB), which underlies the recurrence of early gastric cancer (EGC) following endoscopic submucosal dissection (ESD). Online microRNA (miRNA) target prediction tools were used, which identified PDGFRB as the candidate target gene of miR­499a in gastric cancer cells, and PFGRBR was then confirmed as the direct gene using a luciferase reporter assay system. The Kaplan­Meier method was used to plot recurrence­free curves, which were compared between genotype groups. A negative regulatory association between miR­499a and PDGFRB was established by investigating the relative luciferase activity at different concentrations of miR­499a mimics. Furthermore, as the rs3746444 polymorphism has been previously reported to interfere with the expression of miR­499a, the present study investigated the expression levels of different genotypes, including TT (n=20), TC (n=9) and CC (n=3), the results of which supported the hypothesis that the presence of the minor allele (C) of the rs3746444 polymorphism compromised the expression of miR­499a. The present study also performed polymerase chain reaction and western blot analyses to examine the mRNA and protein expression levels of PFGRBR among different genotypes or cells treated with different concentrations of miR­499a mimics/inhibitors, which indicated the negative regulatory association between miR­499a and PDGFRB. The present study also investigated the relative viabilities of EGC cells transfected with miR­499a mimics (50 and 100 nM) and miR­499a inhibitors (100 nM), and confirmed that miR­499a negatively interfered with the viability of the EGC cells. The miR­499a rs3746444 polymorphism was also recognized as a biomarker to predict recurrence following ESD in patients with EGC via analyzing the recurrence­free rates among patients with EGC with different genotypes. The results showed that PDGFRB was validated as a target of miR­499a, and rs3746444 was identified as a potential biomarker to predict the recurrence of EGC following ESD.

Antitumor effects of oncolytic herpes simplex virus type 2 against colorectal cancer in vitro and in vivo.

BACKGROUND: The incidence of colorectal cancer (CRC) is on the rise. Furthermore, late-stage diagnoses and limited efficacious treatment options make CRC a complex clinical challenge. Therefore, a new therapeutic regimen with a completely novel therapeutic mechanism is necessary for CRC. In the present study, the therapeutic efficacy of oncolytic herpes simplex virus type 2 (oHSV2) in CRC was assessed in vitro and in vivo. oHSV2 is an oncolytic agent derived from herpes simplex virus type 2 that encodes granulocyte-macrophage colony-stimulating factor. MATERIALS AND METHODS: We investigated the cytopathic effects of oHSV2 in CRC cell lines using the MTT assay. Then, cell cycle progression and apoptosis of oHSV2 were examined by flow cytometry. We generated a model of CRC with mouse CRC cell CT26 in BALB/c mice. The antitumor effects and adaptive immune response of oHSV2 were assessed in tumor-bearing mice. The therapeutic efficacy of oHSV2 was compared with the traditional chemotherapeutic agent, 5-fluorouracil. RESULTS: The in vitro data showed that oHSV2 infected the CRC cell lines successfully and that the tumor cells formed a significant number of syncytiae postinfection. The oHSV2 killed cancer cells independent of the cell cycle and mainly caused tumor cells necrosis. The in vivo results showed that oHSV2 significantly inhibited tumor growth and prolonged survival of tumor-bearing mice without weight loss. With virus replication, oHSV2 not only resulted in a reduction of myeloid-derived suppressor cells and regulatory T cells in the spleen, but also increased the number of mature dendritic cells in tumor-draining lymph nodes and the effective CD4+T and CD8+T-cells in the tumor microenvironment. CONCLUSION: Our study provides the first evidence that oHSV2 induces cell death in CRC in vitro and in vivo. These findings indicate that oHSV2 is an effective therapeutic cancer candidate that causes an oncolytic effect and recruits adaptive immune responses for an enhanced therapeutic impact, thus providing a potential therapeutic tool for treatment of CRC.

Robot-assisted versus conventional laparoscopic operation in anus-preserving rectal cancer: a meta-analysis.

OBJECTIVE: The aim of this meta-analysis is to provide recommendations for clinical practice and prevention of postoperative complications, such as circumferential resection margin (CRM) involvement, and compare the amount of intraoperative bleeding, safety, operative time, recovery, outcomes, and clinical significance of robot-assisted and conventional laparoscopic procedures in anus-preserving rectal cancer. METHODS: A literature search (PubMed) was performed to identify biomedical research papers and abstracts of studies comparing robot-assisted and conventional laparoscopic procedures. We attempted to obtain the full-text link for papers published between 2000 and 2016, and hand-searched references for relevant literature. RevMan 5.3 software was used for the meta-analysis. RESULTS: Nine papers (949 patients) were eligible for inclusion; there were 473 patients (49.8%) in the robotic group and 476 patients (50.2%) in the laparoscopic group. According to the data provided in the literature, seven indicators were used to complete the evaluation. The results of the meta-analysis suggested that robot-assisted procedure was associated with lower intraoperative blood loss (mean difference [MD] -41.15; 95% confidence interval [CI] -77.51, -4.79; P=0.03), lower open conversion rate (risk difference [RD] -0.05; 95% CI -0.09, -0.01; P=0.02), lower hospital stay (MD -1.07; 95% CI -1.80, -0.33; P=0.005), lower overall complication rate (odds ratio 0.58; 95% CI 0.41, 0.83; P=0.003), and longer operative time (MD 33.73; 95% CI 8.48, 58.99; P=0.009) compared with conventional laparoscopy. There were no differences in the rate of CRM involvement (RD -0.02; 95% CI -0.05, 0.01; P=0.23) and days to return of bowel function (MD -0.03; 95% CI -0.40, 0.34; P=0.89). CONCLUSION: The Da Vinci robot was superior to laparoscopy with respect to blood loss, open conversion, hospital stay, and postoperative complications during anus-preserving rectal cancer procedures; however, conventional laparoscopy had an advantage regarding operative time. The remaining indicators (CRMs and recovery from intestinal peristalsis) did not differ.

Expression and mechanism of microRNA-181A on incidence and survival in late liver metastases of colorectal cancer.

The emerging role of microRNA-181A (miR-181A) in CRC patients with late liver metastases was studied. In the present study we investigated the association between expression and mechanism of miRNA-181A, liver metastasis and prognosis of colorectal cancer (CRC). The expression of miR-181A and PTEN in CRC patients with late liver metastases was higher than that of the normal (control) group, whereas the expression of miR-181A and PTEN was lower in all pathological groups (TNM I-TNM IV). Overall survival (OS) of lower expression miR-181A CRC patients with late liver metastases was higher than that of higher expression miR-181A CRC patients with late liver metastases. The expression of miR-181A and PTEN in the colon cell line NCM460 was lower than that of the colon cancer SW620 cell line. Upregulation of miR-181A promoted cell viability and inhibited apoptosis of SW620 cells, suppressed PTEN expression and activated phosphorylation of AKT (p-AKT) in SW620 cells. Additionally, downregulation of miR-181A inhibited cell viability of SW620 cells through promotion of PTEN and inhibition of p-AKT. Together, our results indicate that miR-181A expression is associated with CRC patients with late liver metastases through PTEN/AKT signaling.