Effect of GLIM-defined malnutrition on postoperative clinical outcomes in patients with colorectal cancer.

BACKGROUND: Malnutrition is common in colorectal cancer patients. Malnutrition is recognized as a risk factor for adverse postoperative outcomes, yet there are no consistent diagnostic criteria for it. Thus, the Global Leadership Initiative on Malnutrition published new universal criteria. We aimed to investigate the prevalence of malnutrition with the application of Global Leadership Initiative on Malnutrition criteria, and explore the correlations between Global Leadership Initiative on Malnutrition-defined malnutrition and postoperative clinical outcomes in colorectal cancer patients. METHODS: We included a cohort of 918 patients who underwent radical resection surgery for colorectal cancer from July 2014 to October 2019. Malnutrition was diagnosed based on the Global Leadership Initiative on Malnutrition criteria. The associations between nutritional status and postoperative clinical outcomes were analyzed by the Kaplan-Meier method, logistic and Cox regression analyses. RESULTS: Among the included patients, 23.6% were diagnosed as malnutrition based on Global Leadership Initiative on Malnutrition criteria. Global Leadership Initiative on Malnutrition-defined malnutrition was associated with total postoperative complications [odds ratio: 1.497 (1.042-2.152), P = 0.029]. Further, Global Leadership Initiative on Malnutrition-diagnosed malnutrition was an independent risk factor for overall survival [hazard ratio: 1.647 (1.048-2.587), P = 0.030] and disease-free survival [hazard ratio: 1.690 (1.169-2.441), P = 0.005]. CONCLUSIONS: The Global Leadership Initiative on Malnutrition criteria is effective to assess malnutrition. Preoperative malnutrition is associated with postoperative complications, overall survival and disease-free survival in colorectal cancer patients after radical resection surgery.

Sox7 negatively regulates prostate-specific membrane antigen (PSMA) expression through PSMA-enhancer.

BACKGROUND: PSMA expression in the prostate epithelium is controlled by a cis-element, PSMA enhancer (PSME). PSME contains multiple binding sites for Sox proteins, and in this study, we identified Sox7 protein as a negative regulator of PSMA expression through its interaction with PSME. METHODS: The statistical correlation between Sox7 and PSMA mRNA expression was evaluated using five prostate cancer studies from cBioportal. In vitro and in vivo interaction between Sox7 and PSME was evaluated by chromatin immunoprecipitation (ChIP), electrophoretic mobility shift assay (EMSA), and luciferase reporter assay. Synthetic oligonucleotides were generated to define the sites in PSME that interact with Sox7 protein. Sox7 mutants were generated to identify the region of this protein required to regulate PSMA expression. Sox7 was also stably expressed in LNCaP/C4-2 and 22Rv1 cells to validate the regulation of PSMA expression by Sox7 in vivo. RESULTS: Sox7 mRNA expression negatively correlated with PSMA/FOLH1 and PSMAL/FOLH1B mRNA expression in Broad/Cornell, TCGA and MSKCC studies, but not in two studies containing only metastatic prostate tumors. PC-3 cells mostly expressed the 48.5 KDa isoform 2 of Sox7, and the depletion of this isoform did not restore PSMA expression. Ectopic expression of canonical, wild-type Sox7 in C4-2 and 22Rv1 cells suppressed PSMA protein expression. ChIP assay revealed that canonical Sox7 protein preferentially interacts with PSME in vivo, and EMSA identified the SOX box sites #2 and #4 in PSME as required for its interaction. Sox7 was capable of directly binding to PSME and suppressed PSME-mediated transcription. The NLS regions of Sox7, but not its ß-catenin interacting motif, are essential for this suppressing activity. Furthermore, restoration of wild-type Sox7 expression but not Sox7-NLS mutant in Sox7-null prostate cancer cell lines suppressed PSMA expression. CONCLUSIONS: The inactivation of canonical Sox7 is responsible for the upregulated expression of PSMA in non-metastatic prostate cancer.

Dual PI3K-BRD4 Inhibitor SF1126 Inhibits Colorectal Cancer Cell Growth in Vitro and in Vivo.

BACKGROUND/AIMS: Bromodomain-containing protein 4 (BRD4) and phosphatidylinositol 3-kinase (PI3K) are key oncogenic cascades in colorectal cancer (CRC). SF1126 is a novel and potent PI3K-BRD4 dual inhibitor. METHODS: CRC cells and human colon epithelial cells were treated with SF1126. Cell survival was tested by MTT and soft agar colony formation assays. Cell proliferation was tested by BrdU ELISA method. Cell apoptosis was tested by a TUNEL staining method and Histone DNA ELISA. Western blotting was utilized to test the signaling proteins. A HT-29 xenograft mice model was established to study the anti-tumor activity of SF1126 in vivo. RESULTS: SF1126 potently inhibited the survival, proliferation, and progression of the cell cycle in an established CRC cell line (HT-29) and primary human colon cancer cells. Significant activation of apoptosis was detected in SF1126-treated CRC cells. In CRC cells, SF1126 blocked Akt-mammalian target of rapamycin (mTOR) complex1/2 signaling and downregulated BRD4 target proteins (Myc and cyclin D1). Further studies showed that SF1126 activated p38 signaling in CRC cells. In contrast, the p38 inhibitors or p38 short hairpin RNA inhibited SF1126-induced cytotoxicity and apoptosis in CRC cells. In vivo, subcutaneous administration of SF1126 significantly inhibited HT-29 xenograft tumor growth in nude mice. CONCLUSION: SF1126 inhibits CRC cell growth possibly by targeting PI3K-Akt-mTOR, BRD4, and p38 signaling.

p53-inducible gene 3 promotes cell migration and invasion by activating the FAK/Src pathway in lung adenocarcinoma.

The p53-inducible gene 3 (PIG3) is one of the p53-induced genes at the onset of apoptosis, which plays an important role in cell apoptosis and DNA damage response. Our previous study reported an oncogenic role of PIG3 associated with tumor progression and metastasis in non-small cell lung cancer (NSCLC). In this study, we further analyzed PIG3 mRNA expression in 504 lung adenocarcinoma (LUAD) and 501 lung squamous cell carcinoma (LUSC) tissues from The Cancer Genome Atlas database and we found that PIG3 expression was significantly higher in LUAD with lymph node metastasis than those without, while no difference was observed between samples with and without lymph node metastasis in LUSC. Gain and loss of function experiments were performed to confirm the metastatic role of PIG3 in vitro and to explore the mechanism involved in its oncogenic role in NSCLC metastasis. The results showed that PIG3 knockdown significantly inhibited the migration and invasion ability of NSCLC cells, and decreased paxillin, phospho-focal adhesion kinase (FAK) and phospho-Src kinase expression, while its overexpression resulted in the opposite effects. Blocking FAK with its inhibitor reverses PIG3 overexpression-induced cell motility in NSCLC cells, indicating that PIG3 increased cell metastasis through the FAK/Src/paxillin pathway. Furthermore, PIG3 silencing sensitized NSCLC cells to FAK inhibitor. In conclusion, our data revealed a role for PIG3 in inducing LUAD metastasis, and its role as a new FAK regulator, suggesting that it could be considered as a novel prognostic biomarker or therapeutic target in the treatment of LUAD metastasis.

MiR-539 inhibits proliferation and migration of triple-negative breast cancer cells by down-regulating LAMA4 expression.

BACKGROUND: Recent studies have shown that laminin subunit alpha 4 (LAMA4) plays an important role in carcinogenesis. However, its molecular biological function in triple-negative breast cancer (TNBC) has not been entirely clarified. This study investigated the expression of LAMA4 in TNBC and its effect on cell proliferation, migration and invasion. Furthermore, we also identified the potential miRNA directly targeting LAMA4. METHODS: Western blot, Real-time quantitative PCR (qPCR) and immunohistochemical staining (IHC) were used to detect the expression of LAMA4 in TNBC. The effects of LAMA4 on TNBC cell proliferation, migration and invasion were also explored in vitro. The potential miRNA that targets LAMA4 was determined by dual luciferase reporter assay and verified by qPCR and western blot analysis. RESULTS: Our study showed LAMA4 mRNA (p = 0.001) and protein (p = 0.005) expression in TNBC tissue samples were elevated compared with adjacent normal tissue samples, and LAMA4 was mainly expressed in the cytoplasm of breast carcinoma cells. Knockdown of LAMA4 inhibited TNBC cell proliferation, migration and invasion in vitro. Moreover, further study revealed that LAMA4 was a putative target of miR-539, and miR-539 negatively regulated LAMA4 expression by directly targeting its 3'-UTR. CONCLUSIONS: Our study suggested that miR-539 suppressed the expression of LAMA4. LAMA4 plays an important role in tumor progression and may be an important target in treatment of TNBC.

Escin-induced DNA damage promotes escin-induced apoptosis in human colorectal cancer cells via p62 regulation of the ATM/γH2AX pathway.

Escin, a triterpene saponin isolated from horse chestnut seed, has been used to treat encephaledema, tissue swelling and chronic venous insufficiency. Recent studies show that escin induces cell cycle arrest, tumor proliferation inhibition and tumor cell apoptosis. But the relationship between escin-induced DNA damage and cell apoptosis in tumor cells remains unclear. In this study, we investigated whether and how escin-induced DNA damage contributed to escin-induced apoptosis in human colorectal cancer cells. Escin (5-80 µg/mL) dose-dependently inhibited the cell viability and colony formation in HCT116 and HCT8 cells. Escin treatment induced DNA damage, leading to p-ATM and γH2AX upregulation. Meanwhile, escin treatment increased the expression of p62, an adaptor protein, which played a crucial role in controlling cell survival and tumorigenesis, and had a protective effect against escin-induced DNA damage: knockdown of p62 apparently enhanced escin-induced DNA damage, whereas overexpression of p62 reduced escin-induced DNA damage. In addition, escin treatment induced concentration- and time-dependent apoptosis. Similarly, knockdown of p62 significantly increased escin-induced apoptosis in vitro and produced en escin-like antitumor effect in vivo. Overexpression of p62 decreased the rate of apoptosis. Further studies revealed that the functions of p62 in escin-induced DNA damage were associated with escin-induced apoptosis, and p62 knockdown combined with the ATM inhibitor KU55933 augmented escin-induced DNA damage and further increased escin-induced apoptosis. In conclusion, our results demonstrate that p62 regulates ATM/γH2AX pathway-mediated escin-induced DNA damage and apoptosis.

Prediction of cancer progression in a group of 73 gastric cancer patients by circulating cell-free DNA.

BACKGROUND: Circulating cell-free DNA (ccf-DNA) in plasma may contain both specific and non-specific of tumor markers. The concentration and integrity of ccf-DNA may be clinical useful for detecting and predicting cancer progression. METHODS: Plasma samples from 40 healthy controls and 73 patients with gastric cancers (two stage 0, 17 stage I, 11 stage II, 33 stage III, and 10 stage IV according to American Joint Committee on Cancer stage) were assessed respectively. qPCR targeting the Alu repeats was performed using two different sets of primers amplifying the long and short segments. DNA integrity was calculated as a ratio of the long to the short fragments of Alu repeats. RESULTS: Plasma DNA concentration was significantly higher in patients with stage III and IV gastric cancers than in healthy controls (p = 0.028 and 0.029 respectively). The receiver operating characteristic (ROC) curve for discriminating patients with stage III and IV gastric cancers from healthy controls had an area under the curve (AUC) of 0.744 (95% CI, 0.64 to 0.85). Circulating cell-free DNA concentration increased within 21 days following surgery and dropped by 3 months after surgery. CONCLUSIONS: Concentration of ccf-DNA is a promising molecular marker for assessing gastric cancer progression. TRIAL REGISTRATION: Current Controlled Trials ChiCTR-DDT-12002848 , 8 October 2012.

TEM and conventional rectal surgery for T1 rectal cancer: a meta-analysis.

BACKGROUND/AIMS: To compare transanal endoscopic microsurgery (TEM) with conventional radical surgery (CRS) for T1 rectal cancer focusing on safety, feasibility and efficacy of both procedures. METHODOLOGY: An online search of Ovid, Medline, Embase, Pubmed and Cochrane Controlled Trials Register was undertaken to identify studies comparing TEM with CRS published in English between 1984 and March 2010. Only studies comparing TEM with CRS for T1 rectal cancer treatment and with a minimum of 20 cases were included. The parameters compared were postoperative complications, hospital mortality, recurrence rate and 5-year survival. RESULTS: Five studies met screening criteria and 397 patients were enrolled in the meta-analysis; 216 were treated with TEM and the rest received CRS. Complications were observed in 16/196 in the TEM group and 77/163 in the CRS group. The difference was significant (p=0.01). The rate of mortality was 3.68% in CRS group, and 0 in TEM group (p=0.01). The 5-year survival was similar (p=0.84), the TEM group was 80.1% and the CRS group was 81.0%. However, there was more recurrence in the TEM group compared to CRS group (p=0.0004). TEM group was 12.0%, while CRS group was 0.5%. CONCLUSION: Compared with CRS, TEM had significant shorter hospital stay and fewer postoperative complications. TEM is a safe, feasible and effective option for T1 rectal cancer. Though TEM had a slightly higher rate of recurrence than CRS, no significant difference on 5-year survival was observed.

Impact of Body Composition and Physical Function on Quality of Life After Gastrectomy for Gastric Cancer.

PURPOSE: Patients with gastric cancer after gastrectomy often suffer from a decline in their quality of life (QoL), but the relationship between body composition (BC) and physical function on QoL has rarely been studied. This study aims to evaluate and determine the changes in QoL after gastrectomy and the impact of BC and physical function on QoL. METHODS: A total of 311 gastric cancer patients completed EORTC QLQ-C30 and EORTC QLQ-STO22 questionnaires before and 1, 3, 6 months post-surgery. Data including BC, handgrip strength (HGS) and 6-m gait speed (GS) were collected prospectively. Multiple linear regression analysis was used to determine the correlation between QoL and BC, HGS and GS. RESULTS: Patients had significantly worse scores after surgery on most function and symptom scales (p < 0.001), but most of these scales recovered within 6 months after surgery. A higher subcutaneous fat area (SFA)was associated with increased symptom scores 1 month after surgery. A higher GS is associated with a better global health status symptom. CONCLUSION: Patients suffer from a decline in their QoL after gastrectomy for gastric cancer. Intervention strategies aiming at reducing SFA and improving GS may improve the QoL in patients underwent gastrectomy for gastric cancer.

Carcinoma of the right side colon accompanied by Sister Mary Joseph's nodule and inguinal nodal metastases: a case report and literature review.

Umbilical metastases from intraperitoneal malignancies are universally referred to Sister Mary Joseph's nodule (SMJN). The most frequent primary tumor sites include the stomach and ovaries. SMJN caused by colon cancer is uncommon. Likewise, carcinoma of the right side colon metastasizing to inguinal lymph nodes is considered almost impossible. To the best of our knowledge, there is no report of right side colon cancer synchronously involving both the umbilicus and inguinal lymph nodes in the literature. We present a case of right side colon cancer (RSCC) metastasizing to the umbilicus and inguinal lymph nodes, which was confirmed by routine pathological evaluation and immuohistochemistry.

Etiological analysis of parastomal hernia by computed tomography examination.

INTRODUCTION: Parastomal hernia is a common complication after stoma formation. The definitive risk factors for parastomal hernia development remain unclear. AIM: This study evaluated the risk factors through computed tomography (CT) scan of patients with parastomal hernia. MATERIAL AND METHODS: All patients who underwent an operation at our institution from January 2008 to February 2014 were included. We recorded patient-related and operation-related variables, and CT scans were checked. All the variables were analyzed with SPSS 19 to identify the risk factors for parastomal hernia formation. RESULTS: Of the 128 patients who underwent colostomy, 49 (38.3%) developed a parastomal hernia during a median follow-up period of 20.1 months (range: 4-84 months). Hernia development was significantly associated with the thickness of subcutaneous fat in the abdominal wall, the location of the stoma, anteroposterior diameter and horizontal diameter of the body. The defect size of the abdominal wall is another risk factor. The larger the defect size of the abdominal wall, the larger is the parastomal stoma (3.79 ±1.51 vs. 2.13 ±0.74 cm horizontally and 4.90 ±2.25 vs. 2.94 ±0.73 cm vertically, p < 0.001). The hernia contents protrude into the hernial sac through the path of the inner side more than the outer side (77.6% vs. 12.2%). CONCLUSIONS: Our findings in Chinese patients with parastomal hernia match those from Western countries: obesity, the location of the stoma, and the defect size of the abdominal wall are significant risk factors for parastomal hernia formation. The mesenteric region is a weak area, which is a site prone to parastomal hernia, and should be protected.

LY294002 induces p53-dependent apoptosis of SGC7901 gastric cancer cells.

AIM: To study the effects of LY294002, an inhibitor of class I phosphatidylinositol 3-kinase (PI3K), on proliferation and apoptosis of SGC7901 gastric cancer cells. METHODS: The MTT assay was used to determine the cytotoxic effects of LY294002. Cell cycle distribution was analyzed using flow cytometry and apoptosis was assessed using flow cytometry analysis after staining DNA with propidium iodide. Mitochondrial membrane potential was measured using the fluorescent probe JC-1. Expression of p53 and PUMA was determined using real-time RT-PCR and Western blotting analysis. RESULTS: The viability of SGC7901 cells was significantly reduced by LY294002 treatment. Expression of p53 and PUMA was induced, and mitochondrial membrane potential collapsed after treatment with LY294002. LY294002 induced apoptotic cell death. CONCLUSION: Activation of the p53 pathway is involved in LY294002-induced SGC7901 cell death.

A novel LC-MS/MS method for mepivacaine determination and pharmacokinetic study in a single-dose two-period crossover in healthy subjects.

The objective of this work was to develop a simple, selective, and sensitive LC-MS/MS method for the quantitation of the mepivacaine in Chinese biological matrix. The calibration curve of mepivacaine ranged from 0.5 to 2000 ng/mL with the lower limit of quantitation being 0.5 ng/mL. This sensitivity was high enough to describe the profile of blood mepivacaine level versus time. Thereby it was very desirable for the pharmacokinetic study because of its high sensitivity and accuracy. The study used a single-dose two-period crossover design principle. For the pharmacokinetic analysis of plasma, the mean (SD) values obtained were as follows: t1/2, 1.63 (0.43) h; Cmax, 435.3 (67.4) ng/ml; AUC0-t, 1546.9 (339.7) ng/ml·h; AUC0-∞, 1982.3 (421.4) ng/ml·h; Tmax, 0.62 (0.31) h. The validated method has been successfully applied to assess the pharmacokinetic study of mepivacaine after a single administration to Chinese volunteers.

Simple instruments facilitating achievement of transanal total mesorectal excision in male patients.

AIM: To assess the efficacy of a modified approach with transanal total mesorectal excision (taTME) using simple customized instruments in male patients with low rectal cancer. METHODS: A total of 115 male patients with low rectal cancer from December 2006 to August 2015 were retrospectively studied. All patients had a bulky tumor (tumor diameter ≥ 40 mm). Forty-one patients (group A) underwent a classical approach of transabdominal total mesorectal excision (TME) and transanal intersphincteric resection (ISR), and the other 74 patients (group B) underwent a modified approach with transabdominal TME, transanal ISR, and taTME. Some simple instruments including modified retractors and an anal dilator with a papilionaceous fixture were used to perform taTME. The operative time, quality of mesorectal excision, circumferential resection margin, local recurrence, and postoperative survival were evaluated. RESULTS: All 115 patients had successful sphincter preservation. The operative time in group B (240 min, range: 160-330 min) was significantly shorter than that in group A (280 min, range: 200-360 min; P = 0.000). Compared with group A, more complete distal mesorectum and total mesorectum were achieved in group B (100% vs 75.6%, P = 0.000; 90.5% vs 70.7%, P = 0.008, respectively). After 46.1 ± 25.6 mo follow-up, group B had a lower local recurrence rate and higher disease-free survival rate compared with group A, but these differences were not statistically significant (5.4% vs 14.6%, P = 0.093; 79.5% vs 65.1%, P = 0.130). CONCLUSION: Retrograde taTME with simple customized instruments can achieve high-quality TME, and it might be an effective and economical alternative for male patients with bulky tumors.

Preclinical study of cinobufagin as a promising anti-colorectal cancer agent.

Here, we assessed the anti-colorectal cancer (CRC) cell activity of cinobufagin (CBG). We found that CBG exerted potent cytotoxic and anti-proliferative activity against CRC lines (HCT-116 and HT-29) and primary human CRC cells. Meanwhile, it activated apoptosis, and disrupted cell-cycle progression in the cells. At the signaling level, CBG treatment in CRC cells provoked endoplasmic reticulum stress (ER stress), the latter was evidenced by caspase-12 activation, CHOP expression, as well as PERK and IRE1 phosphorylations. Contrarily, the ER stress inhibitor salubrinal, the caspase-12 inhibitor and CHOP shRNA remarkably attenuated CBG-induced CRC cell death and apoptosis. Further, CBG in-activated mammalian target or rapamycin complex 1 (mTORC1), which appeared responsible for proliferation inhibition in CRC cells. Introduction of a constitutively-active S6K1 ("ca-S6K1") restored proliferation of CBG-treated CRC cells. Finally, CBG intraperitoneal injection suppressed HCT-116 xenograft tumor growth in the nude mice. CHOP upregulation and mTORC1 in-activation were also noticed in CBG-treated HCT-116 tumors. The results of this preclinical study suggest that CBG could be tested as promising anti-CRC agent.

Clinical significance of immunohistochemical expression of hypoxia-inducible factor-1alpha as a prognostic marker in rectal adenocarcinoma.

BACKGROUND: Hypoxia-inducible factor-1alpha (HIF-1alpha), a subunit of hypoxia-inducible factor-1 (HIF-1), furnishes tumor cells with the means of adapting to stress parameters, such as tumor hypoxia, and promotes critical steps in tumor progression and aggressiveness by inducing angiogenesis and regulating energy metabolism. In this study, we investigated the relationship between HIF-1alpha and vascular endothelial growth factor (VEGF) and clinicopathologic characteristics, and evaluated the role of HIF-1alpha expression in patients with rectal adenocarcinoma. PATIENTS AND METHODS: The immunohistochemical expression of HIF-1alpha and VEGF was evaluated in 30 formalin-fixed, paraffin-embedded postoperative rectal adenocarcinoma tissue samples. Correlations with clinicopathologic characteristics were determined by cross-tabulations. The impact of the immunoreactivity of HIF-1alpha with regard to the overall survival and local control endpoints was determined by univariate analyses. RESULTS: Increased HIF-1alpha expression was strongly associated with VEGF positivity (P = 0.002), Dukes stage (P = 0.017), and lymph node metastasis (P = 0.001). No correlation was found between the level of HIF-1alpha expression and histologic grade (P = 0.63). The Kaplan-Meier curves showed a significantly shorter overall survival (P = 0.0087) and local control (P = 0.0438) for patients with high HIF-1alpha expression. CONCLUSION: These results show that HIF-1alpha might represent an important biologic marker evaluating the prognosis of patients with rectal adenocarcinoma.

Effects of autophagy regulation of tumor-associated macrophages on radiosensitivity of colorectal cancer cells.

Tumor­associated macrophages (TAMs), a major component of the tumor microenvironment, are crucial to the processes of tumor growth, infiltration and metastasis, and contribute to drug resistance. The importance of TAMs in radiation resistance of colorectal cancer remains unclear. To investigate the effects of autophagy regulation of TAMs on the radiosensitivity of colorectal cancer cells, the current study induced TAM formation from THP­1 monocyte cells. Sequential treatment of THP­1 cells with PMA for 72 h and human recombinant interleukin­4 for 24 h was used to stimulate THP­1 differentiation to TAMs. Expression of the cell surface markers CD68, CD204 and CD206, and changes to cell morphology were used to confirm successful differentiation. The TAMs were stimulated to promote or inhibit autophagy during co­culture with LoVo colorectal adenocarcinoma cells. The cells were irradiated, with subsequent measurement of LoVo colony formation and apoptosis. Additionally, the expression of p53, Bcl­2, survivin and Smac proteins was assessed by western blotting. Monodansylcadaverin staining was used to analyze the presence of autophagic vacuoles in TAM, and western blot analysis was used to assess the expression of Beclin­1, LC3B I and II, ATG­3, ­5 and ­7. The results demonstrated TAM autophagy to be markedly altered by rapamycin and bafilomycin A1 treatment. Following co­culture with TAMs, the colony formation rate and survival fraction of LoVo cells were significantly higher than those in the control group (P<0.05). It was further demonstrated that the regulation of autophagy in TAMs was able to inhibit the colony formation of LoVo colorectal cancer cells. Upregulation of TAM autophagy using rapamycin exhibited more effective inhibition of LoVo colony formation than autophagy downregulation. Notably, apoptosis was significantly increased in LoVo cells when co­cultured with TAMs only, or with rapamycin­mediated autophagy upregulated TAMs, compared with LoVo cells cultured alone (P<0.01). Expression of Bcl­2, survivin and p53 were reduced in LoVo cells co­cultured with TAMs, compared with the control group (P<0.05), whereas Smac expression was increased in the co­culture groups (P<0.01). It was demonstrated that rapamycin­mediated autophagy stimulation in TAMs led to reduced expression levels of survivin and Bcl­2, however, Smac expression was increased. The upregulation of autophagy in TAMs inhibited proliferation and induced apoptosis in colon cancer cells, and altered the expression of radiosensitivity­associated proteins. This data indicated that the radiosensitivity of colorectal cancer cells is associated with autophagy of TAM, and that stimulating TAM autophagy may increase the radiosensitivity of colorectal cancer cells.

Neurogenic differentiation factor NeuroD confers protection against radiation-induced intestinal injury in mice.

The gastrointestinal tract, especially the small intestine, is particularly sensitive to radiation, and is prone to radiation-induced injury as a result. Neurogenic differentiation factor (NeuroD) is an evolutionarily-conserved basic helix-loop-helix (bHLH) transcription factor. NeuroD contains a protein transduction domain (PTD), which allows it to be exogenously delivered across the membrane of mammalian cells, whereupon its transcription activity can be unleashed. Whether NeuroD has therapeutic effects for radiation-induced injury remains unclear. In the present study, we prepared a NeuroD-EGFP recombinant protein, and explored its protective effects on the survival and intestinal damage induced by ionizing radiation. Our results showed that NeuroD-EGFP could be transduced into small intestine epithelial cells and tissues. NeuroD-EGFP administration significantly increased overall survival of mice exposed to lethal total body irradiation (TBI). This recombinant NeuroD also reduced radiation-induced intestinal mucosal injury and apoptosis, and improved crypt survival. Expression profiling of NeuroD-EGFP-treated mice revealed upregulation of tissue inhibitor of metalloproteinase 1 (TIMP-1), a known inhibitor of apoptosis in mammalian cells. In conclusion, NeuroD confers protection against radiation-induced intestinal injury, and provides a novel therapeutic clinical option for the prevention of intestinal side effects of radiotherapy and the treatment of victims of incidental exposure.

Knockdown of long non-coding RNA HOTAIR inhibits proliferation and invasiveness and improves radiosensitivity in colorectal cancer.

Colorectal cancer (CRC) is still one of the most important neoplasias causing human death. Multidisciplinary therapy has won consensus in the management of CRC, of which, radiotherapy occupies an important position. However, radioresistance is still a major obstacle in local control of CRC. Overexpression of long non-coding RNA HOTAIR has been found to correlate with tumorigenesis and poor prognosis in several types of cancer. In the present study, we analyzed HOTAIR expression levels of 53 CRC patients in tumor and adjacent normal tissue by real-time quantitative PCR. Knockdown of HOTAIR by RNA interference was performed to explore its roles in cell proliferation, migration, invasion, apoptosis and radiosensitivity. Results showed that CRC patients had higher HOTAIR expression in tumor tissues compared with adjacent normal tissues. In vitro, downregulation of HOTAIR reduced proliferation, migration and invasiveness while enhanced apoptosis and radio-sensitivity of CRC cells. Taken together, our findings suggest that long non-coding RNA HOTAIR expression is closely associated with tumor invasion and radiosensitivity, indicating the potential role in diagnostics and therapeutics of CRC.

Effects of 5­fluorouracil and class III phosphoinositide 3­kinase small interfering RNA combination therapy on SGC7901 human gastric cancer cells.

The aim of the present study was to investigate the effects of small interfering RNA­mediated inhibition of Class III phosphoinositide 3­kinase (PI3K) signal transduction on the proliferation, apoptosis and autophagy of SGC7901 gastric cancer cells. The present study also aimed to examine the contribution of autophagic inhibition to the antitumor effects of 5­fluorouracil (5­FU). A PI3K(III)­RNA interference (i)­green fluorescent protein (GFP) recombinant replication adenovirus (AD) and the negative control (NC)­RNAi­GFP control AD were constructed and infected into SGC7901 cells. A methyl thiazolyl tetrazolium assay was used to determine the growth rate of the SGC7901 cells. Immunofluorescent staining was used to detect microtubule­associated protein 1 light chain 3 expression. The mitochondrial membrane potential was measured using the JC­1 fluorescent probe. Autophagic expression was monitored with MDC staining and transmission electron microscopy. The results revealed that following combination treatment of the SGC7901 gastric cancer cells with 5­FU + PI3K(III)­RNAi­AD, the optical density absorbance values at 24, 48 and 72 h were 0.17 ± 1.64, 0.13 ± 4.64 and 0.11 ± 3.56%, respectively, with cell viability inhibition ratios of 45.89 ± 6.67, 72.57 ± 9.48 and 87.51 ± 4.65%, respectively. As compared with the other treatment groups, the inhibition rate in the combined treatment group was significantly higher (P<0.05). The percentages of the cells with green fluorescence in the combined treatment group were 74.4 ± 3.86 (24 h), 82.3 ± 1.84 (48 h) and 92.5 ± 1.1% (72 h), which were larger than those of the other groups. The percentage of cells with green fluorescence became larger, which indicated that the mitochondrion membrane potential had been reduced to a greater extent. MDC staining revealed that the number of autophagic vacuoles in the cells (measured at 24, 48 and 72 h) decreased gradually with time, with more autophagic vacuoles observed in the cells in the control group at 24 h than those in the other treatment groups. Fewest autophagic vacuoles were identified in the combined treatment group. Using a fluorescence microscope, the immune fluorescence expression of microtubule­associated proteins 1A/1B light chain 3A, which is the specific protein of autophagy, in the combined treatment group was observed to be significantly downregulated, as compared with the other groups. As determined by transmission electron microscopic observation of the SGC7901 gastric cancer cells, the degree of autophagy in the combined treatment group was significantly reduced, as compared with that of the other treatment groups. In conclusion, following combined treatment with 5­FU and an inhibitor of class III PI3K signal transduction, the proliferation of SGC7901 cells was significantly suppressed, the mitochondrion membrane potentials were significantly reduced and the expression levels of autophagic markers were significantly downregulated.