Schizandrin A exhibits potent anticancer activity in colorectal cancer cells by inhibiting heat shock factor 1.

Heat shock factor 1 (HSF1) is a powerful multifaceted oncogenic modifier that plays a role in maintaining the protein balance of cancer cells under various stresses. In recent studies, there have been reports of increased expression of HSF1 in colorectal cancer (CRC) cells, and the depletion of the HSF1 gene knockdown has inhibited colon cancer growth both in vivo and in vitro. Therefore, HSF1 is a promising target for colon cancer treatment and chemoprevention. In the present study, we found that Schizandrin A (Sch A) significantly inhibited the growth of CRC cell lines by inducing cell cycle arrest, apoptosis and death. Through HSE luciferase reporter assay and quantitative PCR (qPCR), we identified Sch A as a novel HSF1 inhibitor. In addition, Sch A could effectively inhibit the induction of HSF1 target proteins such as heat-shock protein (HSP) 70 (HSP70) and HSP27, whether in heat shock or normal temperature culture. In the Surface Plasmon Resonance (SPR) experiment, Sch A showed moderate affinity with HSF1, further confirming that Sch A might be a direct HSF1 inhibitor. The molecular docking and molecular dynamic simulation results of HSF1/Sch A suggested that Sch A formed key hydrogen bond and hydrophobic interactions with HSF1, which may contribute to its potent HSF1 inhibition. These findings provide clues for the design of novel HSF1 inhibitors and drug candidates for colon cancer treatment.

Circular RNA hsa_circ_000984 promotes colon cancer growth and metastasis by sponging miR-106b.

Circular RNAs (circRNAs) as a novel type of noncoding RNAs (ncRNAs) are widely studied in the development of human various diseases, including cancer. Here, we found circular RNA hsa_circ_000984 encoded by the CDK6 gene was remarkably upregulated in the tissues of colorectal cancer (CRC) patients and in the CRC cell lines. Moreover, high expression level of hsa_circ_000984 was significantly associated with advanced colorectal cancer. Further analysis revealed that hsa_circ_000984 knockdown could inhibit cell proliferation, migration, invasion in vitro and tumor formation in vivo in CRC cell lines. Mechanically, we found that hsa_circ_000984 may act as a competing endogenous RNA (ceRNA) by competitively binding miR-106b and effectively upregulate the expression of CDK6, thereby inducing a series of malignant phenotypes of tumor cells. Taken together, these observations suggest that the hsa_circ_000984 could mediate the expression of gene CDK6 by acting as a ceRNA, which may contribute to a better understanding of between the regulatory miRNA network and CRC pathogenesis.

Lymphovascular invasion is a high risk factor for stage I/II colorectal cancer: a systematic review and meta-analysis.

The prognostic value of lymphovascular invasion (LVI) in stage I/II colorectal cancer (CRC) does not reach a consensus. To systematically assess prognostic significance of LVI, databases of PubMed, Web of Science, and Embase were searched from inception up to 10 Dec 2016. The pooled hazard ratio (HR) and 95% confidence intervals (CI) were used to determine the prognostic effects. Nineteen relevant studies including 9881 total patients were enrolled. Our results showed that LVI is significantly associated with poor prognosis in overall survival (OS) (HR=2.15, 95 % CI=1.72-2.68, P < 0.01) and disease-free survival (DFS) (HR=1.73, 95% CI=1.50-1.99, P < 0.01), which is similar in stage II patients. Further subgroup analysis revealed that the significance of the association between LVI and worse prognosis in CRC patients is not affected by below factors, including geographic setting, LVI positive rate, treatment, tumor site, and quality of the study. The current meta-analysis suggests that LVI may be a poor prognostic factor for stage I/II CRC patients.

Depletion of UBA protein 2-like protein inhibits growth and induces apoptosis of human colorectal carcinoma cells.

Ubiquitin-proteasome system regulates cell proliferation, apoptosis, angiogenesis, and motility, which are processes with particular importance for carcinogenesis. UBA protein 2-like protein (UBAP2L) was found to be associated with proteasome; however, its biological function is largely unknown. In this study, the mRNA levels of UBAP2L in human normal and colorectal carcinoma tissues were analyzed using the datasets from the publicly available Oncomine database ( www.oncomine.org ) and found UBAP2L was overexpressed in colorectal carcinoma tissues. Furthermore, we elucidated the role of UBAP2L in human colorectal cancer via an RNA interference lentivirus system in three colorectal carcinoma cell lines HCT116, SW1116, and RKO. Knockdown of UBAP2L led to suppressed cell proliferation and impaired colony formation. UBAP2L depletion in HCT116 and RKO cells also induced cell cycle arrest as well as apoptosis. Moreover, the phosphorylation of PRAS40, Bad, and the cleavage of PARP were remarkably increased after UBAP2L knockdown by Intracellular signaling array and also the activation of P38 was obviously decreased and the cleavage of Caspase 3 and Bax were increased after UBAP2L silencing by western blot assay, indicated that UBAP2L might be involved in the cell growth by the regulation of apoptosis-related proteins. Our findings indicated that UBAP2L may be essential for colorectal carcinoma growth and survival. Lentivirus-mediated small interfering RNA against UBAP2L might serve as a potential therapeutic approach for the treatment of colorectal cancer.

Clinical research of intraperitoneal implantation of sustained-release 5-fluorouracil in advanced colorectal cancer.

BACKGROUND: The objective of this study was to investigate the safety and long-term clinical effect of intraperitoneal implantation of sustained-release 5-fluorouracil in patients with advanced colorectal cancer during radical resection. METHODS: A total of 202 patients with advanced colorectal cancer undergoing radical operations were randomly divided into an experimental group (98 cases, intraoperative intraperitoneal implantation of sustained-release 5-fluorouracil 600 mg as local chemotherapy) and a control group (104 cases, without local chemotherapy). The clinical data of the two groups was compared including toxicity, complications, local recurrence rate, distant metastasis, disease-free survival, and 1-, 3-, and 5-year survival rates. RESULTS: Both groups of patients were followed up for more than 5 years, the longest follow-up time was 7.5 years. Bone marrow suppression, hepato-renal function, postoperative anastomotic leakage, pelvic effusion, incision infection, the incidence of intestinal obstruction, venting time, and hospital stay after operation (days) between two groups had no statistical significant difference. Locoregional recurrence and liver metastasis rate were decreased significantly in experimental group (P = 0.04 and 0.04). Extensive peritoneal metastasis and other organ metastasis rates had no significant difference between two groups. In the experimental group, 1-, 3-, and 5-year survival rates were higher than in the control group (95.92 vs 87.50 %, 77.55 vs 64.42 %, and 56.12 vs 40.38 %), which had significant difference. Disease-free survival (DFS) of the experimental group was higher than that of the control group (χ (2) = 5.00, P = 0.025). CONCLUSIONS: Intraperitoneal implantation of sustained-release 5-fluorouracil is safe for advanced colorectal cancer during radical resection, which can reduce locoregional recurrence rate and liver metastasis rate. The long-term efficacy was reliable, and long-term survival and disease-free survival rate can be improved.

Functional Genetic Variations at the microRNA Binding-Site in the CD44 Gene Are Associated with Risk of Colorectal Cancer in Chinese Populations.

CD44 as one of the most putative stem cell markers plays a key role in many cellular processes, including cancer cell growth and migration. Functional single nucleotide polymorphisms (SNPs) of CD44 may modulate its gene functions and thus cancer risk. In the current study, we investigated if polymorphisms in the 3'-untranslated region (UTR) of CD44 are associated with increased susceptibility to colorectal cancer (CRC) by conducting a case-control study of 946 CRC patients and 989 cancer-free controls. Three polymorphisms (rs13347C/T, rs10836347C/T, rs11821102G/A) in the 3'-UTR of CD44 were genotyped. We found that the variant genotypes (CT and TT) of rs13347 (adjusted odds ratio (OR)=1.79, 95% confidence interval (CI)=1.50-2.17) increased an individual's susceptibility to CRC, compared with rs13347CC homozygous genotypes. We also found that CRC patients with the CT/TT genotype had a 1.6-fold increased risk for developing advanced (stage III + IV) CRC. Furthermore, functional assays showed that the C to T base change at rs13347C/T disrupts the binding site for the microRNA hsa-mir-509-3p, thereby increasing CD44 transcriptional activity and expression level. These findings suggest that the rs13347C/T in microRNA binding site may be potential biomarkers for genetic susceptibility to CRC.

Downregulation of NIT2 inhibits colon cancer cell proliferation and induces cell cycle arrest through the caspase-3 and PARP pathways.

Colorectal cancer, also known as colon cancer is the most devastating malignancy worldwide. Previous studies have reported that Nit2, a member of the nitrilase superfamily, is a potential tumor suppressor, although its function remains elusive in colon cancer. In the present study, we employed an RNA interference lentivirus system to silence endogenous NIT2 expression in the colon cancer cell line, HCT116. The knockdown efficiency was determined by RT-qPCR and western blot analysis. The depletion of NIT2 markedly inhibited colon cancer cell proliferation and colony formation and induced cell cycle arrest in the G0/G1 phase, as shown by MTT assay, colony formation assay and flow cytometric analysis, respectively. Further investigation with an intracellular signaling array demonstrated that the depletion of NIT2 triggered the apoptosis of colon cancer cells through the caspase-3 and poly(ADP-ribose) polymerase (PARP) pathways. Our findings suggest that NIT2 may be an oncogene in human colon cancer and may thus serve as a promising therapeutic target for the treatment of colon cancer.

Lentivirus-mediated knockdown of eukaryotic translation initiation factor 3 subunit D inhibits proliferation of HCT116 colon cancer cells.

Dysregulation of protein synthesis is emerging as a major contributory factor in cancer development. eIF3D (eukaryotic translation initiation factor 3 subunit D) is one member of the eIF3 (eukaryotic translation initiation factor 3) family, which is essential for initiation of protein synthesis in eukaryotic cells. Acquaintance with eIF3D is little since it has been identified as a dispensable subunit of eIF3 complex. Recently, eIF3D was found to embed somatic mutations in human colorectal cancers, indicating its importance for tumour progression. To further probe into its action in colon cancer, we utilized lentivirus-mediated RNA interference to knock down eIF3D expression in one colon cancer cell line HCT116. Knockdown of eIF3D in HCT116 cells significantly inhibited cell proliferation and colony formation in vitro. Flow cytometry analysis indicated that depletion of eIF3D led to cell-cycle arrest in the G2/M phase, and induced an excess accumulation of HCT116 cells in the sub-G1 phase representing apoptotic cells. Signalling pathways responsible for cell growth and apoptosis have also been found altered after eIF3D silencing, such as AMPKα (AMP-activated protein kinase alpha), Bad, PRAS40 [proline-rich Akt (PKB) substrate of 40 kDa], SAPK (stress-activated protein kinase)/JNK (c-Jun N-terminal kinase), GSK3ß and PARP [poly(ADP-ribose) polymerase]. Taken together, these findings suggest that eIF3D might play an important role in colon cancer progression.

NQO1 C609T polymorphism and colorectal cancer susceptibility: a meta-analysis.

INTRODUCTION: A FEW STUDIES HAVE REPORTED AN ASSOCIATION BETWEEN NADP(H): quinine oxidoreductase 1 (NQO1) C609T polymorphism and susceptibility to colorectal cancer (CRC). However, the results were inconsistent rather than conclusive. We performed a meta-analysis to examine this association in various populations. MATERIAL AND METHODS: Eligible articles were identified by a search of several databases up until June 30, 2013. Summary odds ratios (ORs) and 95% confidence intervals (CIs) were calculated to assess the strength of the association. RESULTS: Overall, 14 case-control studies with 4,461 cases and 5,474 controls were included in this meta-analysis. The results indicated that the NQO1 C609T polymorphism was significantly associated with CRC susceptibility (summary ORs (95% CIs): 1.30 (1.07-1.59) for CT vs. CC, 1.64 (1.15-2.33) for TT vs. CC, 1.34 (1.10-1.64) for TT/CT vs. CC, and 1.43 (1.10-1.87) for TT vs. CT/CC). Subgroup analyses indicated that the T allele was significantly associated with CRC susceptibility in both Asians and Caucasians, and was also observed in high quality studies and hospital-based case-control studies. Specifically, we found a positive association between the NQO1 C609T polymorphism and CRC susceptibility in smokers, but not in non-smokers. CONCLUSIONS: The results of this meta-analysis suggest that the NQO1 C609T polymorphism significantly contributes to increased susceptibility to CRC in both Asians and Caucasians.

Myotubularin-related phosphatase 3 promotes growth of colorectal cancer cells.

Due to changes in lifestyle, particularly changes in dietary habits, colorectal cancer (CRC) increased in recent years despite advances in treatment. Nearly one million new cases diagnosed worldwide and half a million deaths make CRC a leading cause of cancer mortality. In the present study, we aimed to investigate the role of myotubularin-related phosphatase 3 (MTMR3) in CRC cell growth via lentivirus-mediated small interfering RNA (siRNA) transduction in human colon cancer cell lines HCT116 and SW1116. The effect of MTMR3 knockdown on cell growth was evaluated by MTT, colony formation, and flow cytometry assays. The effect of MTMR3 knockdown on cell apoptosis was evaluated by flow cytometry with Annexin V/7-AAD double staining. The activation of apoptotic markers, Bad and PARP, was detected using Intracellular Signaling Array. Knockdown of MTMR3 resulted in a significant reduction in cell proliferation in both HCT116 and SW1116 cells. Moreover, knockdown of MTMR3 led to S phase cell cycle arrest. Furthermore, knockdown of MTMR3 induced cell apoptosis via phosphorylation of Bad and cleavage of PARP. These results indicate that MTMR3 may play an important role in the progression of CRC and suggest that siRNA mediated silencing of MTMR3 could be an effective tool in CRC treatment.

[Relationship between E-CD and Snail expressions and tumor invasion, metastasis and prognosis in colorectal cancer].

OBJECTIVE: To study the E-CD and Snail expressions in colorectal cancer and their relationship with colorectal cancer invasion, metastasis and prognosis. METHODS: Immunohistochemical staining (EnVision) was used to detect the E-CD and Snail expressions in 30 normal colorectal mucosa, 30 colorectal adenoma and 142 colorectal cancer tissues. RESULTS: E-CD in the normal colorectal mucosa was strongly positive expressed (90.0%), significantly higher than that in colorectal adenomas (63.3%) and colorectal cancer tissues (41.5%). E-CD expression was significantly related to tumor differentiation, invasion depth, vascular invasion, lymph node metastasis and Dukes' stage (P < 0.05), but not to the patients' age, gender, tumor size and tumor histological type (P > 0.05). The 1-, 3- and 5-year survival rates of the E-CD positive patients with colorectal cancer were significantly higher than that in E-CD negative patients. The positive expression rate of Snail in colorectal cancer tissues (52.1%) was significantly higher than that in normal colorectal mucosa (6.7%) and colorectal adenomas (26.7%, P < 0.05). The snail expression was significantly correlated to tumor histological type, differentiation, invasion depth, vascular invasion, lymph node metastasis and Duke's stage (P < 0.05), but not to patients' age, sex and tumor size (P > 0.05). The 1-, 3- and 5-year survival rates of Snail negative patients with colorectal cancer was significantly higher than that in patients with positive expression (P < 0.05). The expressions of E-CD and Snail in colorectal cancer tissues were inversely correlated (P < 0.05). Cox multivariate analysis showed that E-CD and Snail can be used as independent prognostic indicators (P < 0.05). CONCLUSION: E-CD and Snail expressions in colorectal cancer are related to the tumor invasion, metastasis and prognosis. Low expression of E-CD and high expression of Snail are related to the advanced stage, and poor prognosis in colorectal cancer patients. E-CD and Snail can be used as independent prognostic indicators.

[Clinical study of a new intracolonic drainage to protect low rectal anastomotic leakage].

OBJECTIVE: To investigate the value of using protective new intracolonic drainage in decreasing low colorectal anastomotic leakage. METHODS: One hundred and nineteen cases of rectal cancer accepted low anterior resection were randomly assigned to study group (n=55) and control group (n=64). The study group was added with a new intracolonic drainage composed of biofragmentable anastomosis ring and condom during operation. The control group was added with protective ileostomy during operation. The results of surgery were compared between the two groups. RESULTS: All the cases were followed up over three months and there were no perioperative death. There were no significant differences in physiopathological factors such as age, sex, body type, site of tumor, size of tumor, differentiation of tumor, site of anastomosis, condition of nutrition, concomitant disease between the two groups. In the study group, anastomotic leakage occurred in 4 cases (7.3%), the drainage devices were ablated 18.3 days after operations and there were no drainage-related complications; light anastomotic stenosis occurred in 3 cases (5.5%) three months after operations. Among the cases with leakage, no severe abdominal infection was found, the time of abdominal drainage was 4.8 days, and the amount of abdominal drainage was 12.8 ml/d in primary three days after leakage. In the control group, anastomotic leakage occurred in 7 cases (10.9%), ostomy-related complications occurred in 29 cases (45.3%), anastomotic stenosis occurred in 18 cases (28.1%) and severe anastomotic stenosis occurred in 4 cases (6.3%) after three months. Among the cases with leakage, severe infection occurred in two cases, anastomotic spoiled occurred in one case, the amount of abdominal drainage was 35.4 ml/d in primary three days after leakage, and the time of abdominal drainage was 17.1 days. There was no significant difference in the rate of anastomotic leakage between the two groups (P>0.05). But there were significant differences in the amount of abdominal drainage, the time of abdominal drainage and abdominal infection in the cases of anastomotic leakage (P<0.01). There was significant difference in anastomotic stenosis after three months between the two groups (P<0.01). CONCLUSIONS: The intracolonic drainage is a simple, safe and effective method in protecting low colorectal anastomotic leakage, and avoiding harmful results caused by anastomotic leakage. Compared with protective ileostomy, intracolonic drainage can avoid stomy-related physical mental suffering and complications, the rate of later anastomotic stenosis is less, and the time of abdominal drainage is shorter in the cases with leakage.

[Surgical treatment for local recurrence of rectal carcinoma after operation].

OBJECTIVE: To evaluate the value of reoperation for local recurrence of rectal carcinoma. METHODS: The data of 62 cases with post-operative local recurrence of rectal carcinoma were analyzed retrospectively. RESULTS: All the 62 patients received reoperation. Thirty two of those patients were treated with radical resection (16 patients combined multiple organ resection), 6 palliative resection, 11 colostomy, and 13 laparatomy only. The 1-, 3- and 5-year survival rates in the patients accepted radical resection were 90.6%, 59.4% and 18.8% respectively. But in patients undergone palliative resection and combined therapy, survival time was 6-24 months with median survival time of 16 months. The patients, accepted laparatomy and intra-abdominal chemotherapy, all died within 2-14 months postoperatively. For patients with postoperative recurrence time >5 years, <2 years and 2-5 years, the reoperation resection rates were 100%(11/11), 62.9%(22/35), and 31.3%(5/16) respectively, and there were significant differences among 3 groups (P<0.01). The rate of reoperation resection of pure local recurrence was 80.0%(32/40). The rate of reoperation resection of local recurrence, associated with near organ invasion, was 27.3%(6/22). The difference was significant(P<0.01). The reoperation resection rate of first operation with Dixon or Miles was 61.9%(26/42) and 30.0%(6/20), and the difference was significant as well(P<0.05). CONCLUSIONS: The recurrence of rectal carcinoma still needs positive operation in order to prolong the survival time and improve the quality of life of the patient. First operative procedure, post-operative recurrence time and recurrence type are important factors of reoperative resection.

[Rule of lymph node metastasis in colorectal cancer and its affecting factors].

OBJECTIVE: To investigate the rule of lymph node metastasis in colorectal cancer and its affecting factors, and to provide clues for clinical diagnosis and treatment of colorectal cancer patients. METHODS: The clinical data of 1166 cases of colorectal cancer receiving surgical resection were analyzed retrospectively.The relationships between clinicopathologic variables and lymph node metastases were evaluated by crosstabs and logistic regression in SPSS 10.0 for windows. RESULTS: The rate of lymph node metastasis in colorectal cancer was 49.7%. After entering crosstabs estimation, gender and tumor site were not significantly correlated with lymph node metastasis in colorectal cancer(chi2=1.46, r=0.035, P>0.05 and chi2=3.86, r=0.012, P>0.05). Age, tumor size, the massive type of the tumor, the differentiating degree of the tumor, histology type and the depth of tumor invasion were proved to be independent factors influencing the lymph node metastasis in colorectal cancer (chi2 =13.1, r=0.064, P<0.05 and chi2=77.161, r=0.245, P<0.01 and chi2=144.831, r=0.341, P<0.01 and chi2=128.310, r=0.318, P<0.01 and chi2=120.418, r=0.319, P<0.01 and chi2=227.287, r=0.434, P<0.01). After entering logistic regression estimation, the correlativity of risk factor of lymph node metastasis in colorectal cancer: the depth of tumor invasion > the massive type of the tumor>the differentiating degree of the tumor > tumor size. Preoperative blood serum CEA level was significantly correlated with lymph node metastasis (chi2=509.599, r=0.661, P<0.01). CONCLUSION: The depth of tumor invasion is the most risk factor of lymph node metastasis in colorectal cancer. Preoperative high level of blood serum CEA indicates the occurrence of lymph node metastasis.