Determination of the ED95 of intranasal sufentanil combined with intranasal dexmedetomidine for moderate sedation during endoscopic ultrasonography.

BACKGROUND: Sedation during endoscopic ultrasonography (EUS) poses many challenges and moderate-to-deep sedation are often required. The conventional method to preform moderate-to-deep sedation is generally intravenous benzodiazepine alone or in combination with opioids. However, this combination has some limitations. Intranasal medication delivery may be an alternative to this sedation regimen. AIM: To determine, by continual reassessment method (CRM), the minimal effective dose of intranasal sufentanil (SUF) when combined with intranasal dexmedetomidine (DEX) for moderate sedation of EUS in at least 95% of patients (ED95). METHODS: Thirty patients aged 18-65 and scheduled for EUS were recruited in this study. Subjects received intranasal DEX and SUF for sedation. The dose of DEX (1 µg/kg) was fixed, while the dose of SUF was assigned sequentially to the subjects using CRM to determine ED95. The sedation status was assessed by modified observer's assessment of alertness/sedation (MOAA/S) score. The adverse events and the satisfaction scores of patients and endoscopists were recorded. RESULTS: The ED95 was intranasal 0.3 µg/kg SUF when combined with intranasal 1 µg/kg DEX, with an estimated probability of successful moderate sedation for EUS of 94.9% (95% confidence interval: 88.1%-98.9%). When combined with intranasal 1 µg/kg DEX, probabilities of successful moderate sedation at each dose level of intranasal SUF were as follows: 0 µg/kg SUF, 52.8%; 0.1 µg/kg SUF, 75.4%; 0.2 µg/kg SUF, 89.9%; 0.3 µg/kg SUF, 94.9%; 0.4 µg/kg SUF, 98.0%; 0.5 µg/kg SUF, 99.0%. CONCLUSION: The ED95 needed for moderate sedation for EUS is intranasal 0.3 µg/kg SUF when combined with intranasal 1 µg/kg DEX, based on CRM.

Prospective, randomized comparison of two supplemental oxygen methods during gastroscopy with propofol mono-sedation in obese patients.

BACKGROUND: Hypoxemia is a common complication in obese patients during gastroscopy with sedation. The Wei nasal jet tube (WNJT) is a new special nasopharyngeal airway with the ability to provide supraglottic jet ventilation and oxygen insufflation via its built-in wall channels. The aim of this study was to compare the efficacy and safety of the WNJT vs a nasal cannula for supplemental oxygen during gastroscopy with propofol mono-sedation in obese patients. AIM: To compare the efficacy and safety of the WNJT vs a nasal cannula for supplemental oxygen during gastroscopy with propofol mono-sedation in obese patients. METHODS: A total of 103 obese patients with a body mass index of 30 kg/m2 or more undergoing elective gastroscopy under propofol mono-sedation were randomly assigned to receive supplemental oxygen at 5 L/min through either a WNJT (WNJT group, n = 51) or a nasal cannula (nasal cannula group, n = 52). The lowest pulse oxygen saturation (SpO2) and mild and severe hypoxemia during gastroscopy were recorded. The primary outcome was the incidence of hypoxemia. RESULTS: The lowest SpO2 during gastroscopy with propofol mono-sedation was significantly increased in the WNJT group compared with the nasal cannula group. The incidence of mild hypoxemia and total incidence of hypoxemia were significantly lower in the WNJT group than in the nasal cannula group. Other than a higher incidence of epistaxis in the WNJT group, the occurrence of adverse events was similar between the devices. While neither device demonstrated a statistically significant difference in satisfaction among patients, the WNJT did result in improved satisfaction among anesthetists and physicians. CONCLUSION: During gastroscopy with propofol mono-sedation in obese patients, the WNJT, when compared with a nasal cannula for supplemental oxygen, can significantly reduce the occurrence of hypoxemia and improve both arterial oxygenation and satisfaction among anesthetists and physicians. The use of the WNJT may, however, lead to epistaxis in a few patients. In view of this clinically acceptable risk-benefit ratio, the WNJT may be recommended as an alternative tool for supplemental oxygen for the prevention of hypoxemia during gastroscopy with propofol mono-sedation in obese patients.

Helicobacter pylori infection is associated with the co-occurrence of bacteria in the oral cavity and the gastric mucosa.

BACKGROUND: Pathogens capable of impacting gastrointestinal tract tumor development are located in the oral cavity, but whether these oral bacteria are able to colonize the gastric mucosa in gastric cancer (GC) patients and whether Helicobacter pylori infection can influence this process remains to be established. METHODS: Microbial 16S rDNA deep sequencing was conducted to characterize bacteria present in paired gastric mucosa and tongue coating samples in 27 patients with superficial gastritis (SG) and 11 GC patients. RESULTS: While the overall composition of the gastric mucosa and tongue coating microbiomes differed substantially, certain bacteria were present in both of these communities. The co-occurrence of bacteria between the tongue coating and gastric mucosa differed significantly between SG and GC patients. Of the 15 most abundant shared oral bacteria genera (the core shared oral bacteria), which were associated with differences in microbiota composition between these tongue coating and gastric mucosa, three were enriched in the gastric mucosa of GC patients relative to SG patients, whereas, 12 were depleted in GC patient samples. Furthermore, the prevalence and relative abundance of these core shared oral bacteria in the gastric mucosa were also linked to H. pylori infection status, and the core shared oral bacteria were also associated with the overall composition of the gastric mucosal microbiome. CONCLUSIONS: Helicobacter pylori infections are linked to the co-occurrence of bacteria in the oral microbiome and the gastric mucosal microbiome. Ectopic colonization of oral microbes may be a primary driver of H. pylori-induced gastric microbial dysbiosis in patients with GC.

A Comparison of Tumor-Associated and Non-Tumor-Associated Gastric Microbiota in Gastric Cancer Patients.

BACKGROUND: How gastric cancer (GC) incidence is associated with changes in the gastric microbiome has not been firmly established. The present study therefore aims to investigate the microbial communities present within the gastric mucosa of patients with superficial gastritis (SG) or GC. METHODS: Paired tumor and paracancerous samples of the gastric mucosa were collected from 18 patients being surgically treated for GC and from 32 patients with SG being treated via gastroscopy. The gastric microbiome in these samples was then profiled via 16S rRNA sequencing, with a linear discriminant analysis effect size (LEfSe) approach used to identify and compare different bacteria, and with PICRUSt used for predictive functional analyses. RESULTS: GC patients exhibited a distinct gastric microbiota profile from that observed in SG patients. These changes were evident in both tumor and paracancerous tissues from GC patients. Specifically, we found that 6 bacterial genera were specifically enriched in GC tissue samples relative to SG samples, while 18 genera were depleted in these same samples. Based on the differential abundance of these bacteria, we were able to calculate microbial dysbiosis index (MDI) values, which were significantly higher in GC patients than in SG patients. In addition, MDI values were negatively correlated with gastric Shannon index and were positively correlated with relative Helicobacter spp. abundance. Importantly, these MDI values were readily able to discriminate between GC and SG patient samples. Functional analysis suggested that GC patients were more likely to harbor a nitrosating microbial community. CONCLUSIONS: GC patients exhibited a gastric microbiome profile distinct from that observed in SG patients, with these differences being evident in both tumor and paracancerous tissues. Differences in the relative abundance of Helicobacter spp. may be the primary driver of gastric dysbiosis in GC patients.

Comparison of two supplemental oxygen methods during gastroscopy with propofol mono-sedation in patients with a normal body mass index.

BACKGROUND: Hypoxemia due to respiratory depression and airway obstruction during upper gastrointestinal endoscopy with sedation is a common concern. The Wei nasal jet tube (WNJT) is a new nasopharyngeal airway with the ability to provide supraglottic jet ventilation and oxygen insufflation via its built-in wall channel. The available evidence indicates that with a low oxygen flow, compared with nasal cannula, the WNJT does not decrease the occurrence of hypoxemia during upper gastrointestinal endoscopy with propofol sedation. To date, there has been no study assessing the performance of WNJT for supplemental oxygen during upper gastrointestinal endoscopy with sedation when a moderate oxygen flow is used. AIM: To determine whether the WNJT performs better than the nasal prongs for the prevention of hypoxemia during gastroscopy with propofol mono-sedation when a moderate oxygen flow is provided in patients with a normal body mass index. METHODS: This study was performed in 291 patients undergoing elective gastroscopy with propofol mono-sedation. Patients were randomized into one of two groups to receive either the WNJT (WNJT group, n = 147) or the nasal cannula (nasal cannula group, n = 144) for supplemental oxygen at a 5-L/min flow during gastroscopy. The lowest SpO2 during gastroscopy was recorded. The primary endpoint was the incidence of hypoxemia or severe hypoxemia during gastroscopy. RESULTS: The total incidence of hypoxemia and severe hypoxemia during gastroscopy was significantly decreased in the WNJT group compared with the nasal cannula group (P = 0.000). The lowest median SpO2 during gastroscopy was significantly higher (98%; interquartile range, 97-99) in the WNJT group than in the nasal cannula group (96%; interquartile range, 93-98). Epistaxis by device insertion in the WNJT group occurred in 7 patients but stopped naturally without any treatment. The two groups were comparable in terms of the satisfaction of physicians, anesthetists and patients. CONCLUSION: With a moderate oxygen flow, the WNJT is more effective for the prevention of hypoxemia during gastroscopy with propofol mono-sedation compared with nasal prongs, but causing slight epistaxis in a few patients.

Comparison of two supplement oxygen methods during gastroscopy with intravenous propofol anesthesia in obese patients: study protocol for a randomized controlled trial.

BACKGROUND: Hypoxemia is a major complication in obese patients undergoing gastrointestinal endoscopy under intravenous anesthesia or sedation due to altered airway anatomy. We design this randomized controlled trial (RCT) to compare efficacy and safety of the Wei nasal jet tube (WNJT) and nasal prongs for supplement oxygen during gastroscopy with intravenous propofol anesthesia in obese patients. METHODS: The study will be a single-center, prospective RCT. A total of 308 obese patients will be recruited and randomly assigned to receive either the WNJT (group A) or nasal prongs (group B). During gastroscopy with intravenous propofol anesthesia, 5 L/min of oxygen will be delivered through the jet port of the WNJT in the group A and via the nasal prongs in the group B. The primary outcome is the incidence of hypoxemia and severe hypoxemia. The secondary outcomes are adverse events during the gastroscopy, postoperative complications, and satisfaction of the anesthetist, physician, and patient. DISCUSSION: This RCT aims to clarify whether the WNJT can result in reduced incidences of hypoxemia and complications and provide improved satisfaction to the anesthetist, physician, and patient. Thus, it can be determined if the WNJT is a useful tool for supplement oxygen in obese patients undergoing gastroscopy with intravenous propofol anesthesia. The results will provide the evidence for anesthesiologists to make a decision regarding the choice of supplementary oxygen methods in this condition. TRIAL REGISTRATION: Chinese Clinical Trial, ChiCTR-IOR-17013089 . Registered on 23 October 2017.

Efficacy and safety of using premedication with simethicone/Pronase during upper gastrointestinal endoscopy examination with sedation: A single center, prospective, single blinded, randomized controlled trial.

BACKGROUND AND AIM: To investigate the efficacy and safety of premedication with simethicone/Pronase during esophagogastroduodenoscopy (EGD) with sedation. METHODS: Six hundred and ten patients were randomly allocated to two groups based on type of premedication given. Premedication used in the control group was 10 mL lidocaine hydrochloride mucilage (LHM, N = 314) and premedication used in the intervention group was 80 mL simethicone/Pronase solution plus 10 mL lidocaine hydrochloride mucilage (SP/LHM, N = 296). EGD was done under sedation. Visibility scores, number of mucosal areas that needed cleansing, water consumption for cleansing, time taken for examination, diminutive lesions, pathological diagnosis, patients' gag reflex and oxygenation (pulse oximetry) were recorded. RESULTS: SP/LHM has significantly lower total visibility score than LHM (7.978 ± 1.526 vs 6.348 ± 1.097, P < 0.01). During the procedure, number of intragastric areas that needed cleansing and amount of water consumed were significantly less in the SP/LHM than in the LHM group (P < 0.01). In SP/LHM (P = 0.01), endoscopy procedure duration was significantly longer. Although there was no significant difference in rate of detection of diminutive lesions between LHM and SP/LHM, the endoscopist carried out more biopsies in SP/LHM. This led to a higher rate of diagnosis of atrophic gastritis (P = 0.014) and intestinal metaplasia (P = 0.024). There was no significant difference in gag reflex (P = 0.604) and oxygenation during the endoscopy procedure for either group of patients. CONCLUSION: Routine use of premedication with simethicone/Pronase should be recommended during EGD with sedation.

Identification of RING-box 2 as a potential target for combating colorectal cancer growth and metastasis.

Development of cancer metastasis is a key contributor to mortality in patients with colorectal cancer. High expression of RING-box 2 (RBX2) in cancer cells is known to play a key role in tumor progression. However, the role of RBX2 in colorectal cancer progression is not well elucidated. In this study, we silenced RBX2 via CRISPR/Cas9 in two colorectal cancer cell lines, HCT116 and SW480. RBX2 knockout attenuated proliferation, colony formation and enhanced sensitivity of colorectal cancer cells to paclitaxel treatment. Invasive property of HCT116 and SW480 cells was also attenuated by RBX2 silencing. We confirmed that increased RBX2 correlated with higher tumor cells growth and metastasis abilities by ectopic expression of RBX2 in HCT116 and SW480 cells. In vivo studies suggested that knockout of RBX2 inhibited xenografts growth and metastasis to lung tissue, whereas ectopic expression of RBX2 promoted these cellular functions. Mechanically, RBX2 induced gastric cancer cell growth and metastasis by activating mammalian target of rapamycin/S6 kinase 1 (mTOR/S6K1). Treatment of everolimus, the specific mTOR inhibitor, significantly attenuated RBX2-mediated cell proliferation and mobility in vitro. Taken together, these results revealed a novel role of RBX2 in colorectal cancer cell growth and metastasis via the mTOR pathway and suggested RBX2 may serve as a therapeutic target in colorectal cancer.

FOXQ1 promotes cancer metastasis by PI3K/AKT signaling regulation in colorectal carcinoma.

Colorectal cancer is one of the major health problems, with invade surrounding tissues, and migrate to distant organs being the most critical concern, thus identified metastasis associated hallmarks and more efficacious treatment are urgently needed. It found that forkhead box q1 (FOXQ1) is aberrant expression in variety of human cancers and FOXQ1 is involved in oncogenic pathways. However, the role of FOXQ1 has been unexplored in colorectal cancer metastasis to date. Here, expression of FOXQ1 was higher in colorectal cancer tissue samples and cancer cell lines than in normal colorectal tissue and cell lines. Further research suggested that FOXQ1 positively regulated cell proliferation in colorectal cancer and down-regulation of CDK6, extracellular regulated protein kinases 1/2 (ERK1/2) and mammalian target of rapamycin (mTOR). In corresponding to this result, over-expression of FOXQ1 significantly promoted colorectal cancer growth in vivo. Moreover, down regulation of FOXQ1 expression in colorectal carcinoma cell HCT116 and LOVO strikingly inhibits tumor growth in vivo. Finally, FOXQ1-dependent inhibition of colorectal cancer cell migration and invasion and down-regulation of focal adhesion kinase (FAK), phosphatidyl inositol 3-kinase (PI3K) phosphorylation, AKT (v-akt murine thymoma viral oncogene) phosphorylation and matrix metalloproteinase-2/9 (MMP-2/9) expression. These integrated efforts have identified FOXQ1 as a tumor promoter and might provide promising approaches for colorectal cancer metastasis treatment.

Identification of HRAS as cancer-promoting gene in gastric carcinoma cell aggressiveness.

Gastric carcinoma is one of the most lethal malignancies of cancers and its prognosis remains dismal due to the paucity of effective therapeutic targets. Herein, we showed that HRAS is markedly up-regulated in gastric carcinoma. Prognostic analysis indicated that HRAS expression might be a prognostic indicator for the survival of patients with gastric carcinoma. Ectopic expression of HRAS in gastric carcinoma cells accelerated proliferation, migration, invasion, angiogenesis, and clone formation ability of gastric carcinoma cells in vitro. Furthermore, HRAS over-expressing significantly promoted the tumorigenicity of gastric carcinoma cells in vivo whereas silencing endogenous HRAS caused opposite outcomes. Moreover, we demonstrated that HRAS enhanced gastric carcinoma aggressiveness by activating VEGFA/PI3K/AKT pathway and Raf-1 signaling. Together, our results provide new evidence that HRAS overexpression promotes the progression of gastric carcinoma and might represent a novel therapeutic target for its treatment.

Regional Arterial Infusion Chemotherapy improves the Pathological Response rate for advanced gastric cancer with Short-term Neoadjuvant Chemotherapy.

To identify clinicopathologic and treatment variables that could predict pathologic tumor response to short-term neoadjuvant chemotherapy (NAC) for patients with locally advanced gastric cancer. A retrospective analysis was conducted of 178 patients who underwent short-term NAC with EOX regimen followed by surgery from January 2008 to December 2010. Neoadjuvant treatment response was evaluated using tumor regression grade. Relationships between pathologic tumor response and clinicopathological factors were evaluated using logistic regression analysis. The benefits of regional arterial infusion chemotherapy were investigated separately. The postoperative pathological response rate was 46.1% (82/178) and 4 patients (2.2%) had complete pathological remission. Pathological response was significantly associated with tumor differentiation (P = 0.008), abnormal a-fetoprotein levels (P = 0.01) and administration approach to chemotherapy (intravenous versus regional arterial infusion chemotherapy) (P = 0.018). Most bone marrow toxicities, vomiting, nausea, alopecia, and fatigue were acceptable. Grade 3/4 toxicities were not commonly observed. The 3-year overall survival (OS) and recurrence free survival (RFS) were 67.0% and 53.0%, respectively. Regional arterial infusion NAC group had significantly better median RFS (48.0 versus 34.0 months) than the intravenous NAC group (P = 0.049). In conclusion, regional arterial infusion NAC can improve the pathological response rate of advanced gastric cancer treated with EOX regimen.

Formononetin, a novel FGFR2 inhibitor, potently inhibits angiogenesis and tumor growth in preclinical models.

Most anti-angiogenic therapies currently being evaluated in clinical trials target vascular endothelial growth factor (VEGF) pathway, however, the tumor vasculature can acquire resistance to VEGF-targeted therapy by shifting to other angiogenesis mechanisms. Therefore, other potential therapeutic agents that block non-VEGF angiogenic pathways need to be evaluated. Here we identified formononetin as a novel agent with potential anti-angiogenic and anti-cancer activities. Formononetin demonstrated inhibition of endothelial cell proliferation, migration, and tube formation in response to basic fibroblast growth factor 2 (FGF2). In ex vivo and in vivo angiogenesis assays, formononetin suppressed FGF2-induced microvessel sprouting of rat aortic rings and angiogenesis. To understand the underlying molecular basis, we examined the effects of formononetin on different molecular components in treated endothelial cell, and found that formononetin suppressed FGF2-triggered activation of FGFR2 and protein kinase B (Akt) signaling. Moreover, formononetin directly inhibited proliferation and blocked the oncogenic signaling pathways in breast cancer cell. In vivo, using xenograft models of breast cancer, formononetin showed growth-inhibitory activity associated with inhibition of tumor angiogenesis. Moreover, formononetin enhanced the effect of VEGFR2 inhibitor sunitinib on tumor growth inhibition. Taken together, our results indicate that formononetin targets the FGFR2-mediated Akt signaling pathway, leading to the suppression of tumor growth and angiogenesis.

Cyclooxygenase-2 knockdown using retinoic acid chalcone (RAC), a promising therapeutic strategy for colon cancer.

Retinoic acid is an effective agent in the treatment of epithelial and hematological malignancies. The present study demonstrates that retinoic acid chalcone (RAC), an analogue of retinoic acid inhibits cell proliferation and induces apoptosis in HCT-15 and CT26.WT colon cancer cell lines. In HCT-15 cells the percentage of apoptotic cells increased from 32.4 ± 3, 45.0 ± 3 to 72.6 ± 5% respectively at 10, 15 and 20 µg/mL compared to 3.7% in control. Similarly in CT26.WT cells the percentage increased from 28.6 ± 3, 41.2 ± 3 to 65.4 ± 5% on treatment with 10, 15 and 20 µg/mL concentrations of RAC after 72 h compared to 2.9 ± 1% in control. Western blotting, fluorescence-activated cell sorting analysis and reverse transcription-PCR assays were used to investigate these effects. RAC inhibited the overexpression of COX-2, PGE2 and PGE2 receptor (EP1 and EP4) in the colon cancer cell lines. RAC mediated inhibition of cell growth and induction of apoptosis through COX-2 inhibition was also confirmed by treating the HCT-15 and CT26.WT colon cancer cells with COX-2 inhibitor, indomethacin and transfection of cells with COX-2 small interfering RNA. In nude mice with tumor xenografts, treatment with RAC-supplemented diet caused inhibition of COX-2, PGE2, and PGE2 receptors (EP1, EP3, and EP4) in tumors. Thus RAC can be a potential candidate for the treatment of colon cancer through the inhibition of COX-2 expression and subsequent inhibition of PGE2 and PGE2 receptors.

Prognosis after resection for hepatitis B virus-associated intrahepatic cholangiocarcinoma.

AIM: To investigate the prognostic factors after resection for hepatitis B virus (HBV)-associated intrahepatic cholangiocarcinoma (ICC) and to assess the impact of different extents of lymphadenectomy on patient survival. METHODS: A total of 85 patients with HBV-associated ICC who underwent curative resection from January 2005 to December 2006 were analyzed. The patients were classified into groups according to the extent of lymphadenectomy (no lymph node dissection, sampling lymph node dissection and regional lymph node dissection). Clinicopathological characteristics and survival were reviewed retrospectively. RESULTS: The cumulative 1-, 3-, and 5-year survival rates were found to be 60%, 18%, and 13%, respectively. Multivariate analysis revealed that liver cirrhosis (HR = 1.875, 95%CI: 1.197-3.278, P = 0.008) and multiple tumors (HR = 2.653, 95%CI: 1.562-4.508, P < 0.001) were independent prognostic factors for survival. Recurrence occurred in 70 patients. The 1-, 3-, and 5-year disease-free survival rates were 36%, 3% and 0%, respectively. Liver cirrhosis (HR = 1.919, P = 0.012), advanced TNM stage (stage III/IV) (HR = 2.027, P < 0.001), and vascular invasion (HR = 3.779, P = 0.02) were independent prognostic factors for disease-free survival. Patients with regional lymph node dissection demonstrated a similar survival rate to patients with sampling lymph node dissection. Lymphadenectomy did not significantly improve the survival rate of patients with negative lymph node status. CONCLUSION: The extent of lymphadenectomy does not seem to have influence on the survival of patients with HBV-associated ICC, and routine lymph node dissection is not recommended, particularly for those without lymph node metastasis.

Impact of occult hepatitis B virus infection on outcome after resection for non-B non-C hepatocellular carcinoma.

BACKGROUND: To investigate the clinicopathologic characteristics of patients with both hepatitis B virus-surface antigen and hepatitis C virus antibody negative hepatocellular carcinoma (non-B non-C HCC [NBNC-HCC]) and examine the impact of occult hepatitis B virus infection (OBI) on patients' survival. METHODS: All patients with OBI were identified from a database of patients with NBNC-HCC who underwent surgical resection between January 1, 2006, and December 31, 2008. Their clinicopathologic and survival characteristics were compared with NBNC-HCC patients without OBI. RESULTS: Out of the 86 NBNC-HCC patients, 59 patients (68.6%) with OBI. A higher prevalence of hepatitis B core antigen positive rate, low platelet count, portal hypertension, and liver cirrhosis were observed in NBNC-HCC patients with OBI. The 1- and 3-y recurrence free survival rates were 66% and 25% in OBI group and 89% and 70% in the no OBI group, respectively (P < 0.001). The 1-, 3-, and 5-y overall survival rates were 86%, 55%, and 51% in OBI group and 93%, 85%, and 66% in no OBI group, respectively (P = 0.112). Multivariate analysis revealed that OBI (hazard ratio [HR] = 2.122; 95% confidence interval [CI], 1.086-4.149; P = 0.028), liver cirrhosis (HR = 2.411; 95% CI, 1.337-4.345; P = 0.003), and vascular invasion (HR = 5.858; 95% CI, 2.799-12.261; P < 0.001) were independent poor prognostic factors for recurrence free survival of patients with NBNC-HCC. CONCLUSIONS: NBNC-HCC patients with OBI had a poorer prognosis. OBI can be a useful predictor for recurrence in patients with NBNC-HCC after surgery.

Insulin-like growth factor receptor-1 overexpression is associated with poor response of rectal cancers to radiotherapy.

AIM: To explore the potential correlation between insulin-like growth factor receptor-1 (IGF-1R) expression and rectal cancer radiosensitivity. METHODS: Eighty-seven rectal cancer patients (cTNM I-III) treated in our department between January 2011 and December 2012 were enrolled. All subjects were treated with preoperative radiotherapy and radical resection of rectal carcinoma. Immunohistochemistry and reverse transcription polymerase chain reaction (RT-PCR) were performed to detect IGF-1R expression in pre-treatment and postoperative colorectal cancer specimens. Radiosensitivity for rectal cancer specimens was evaluated by observing rectal carcinoma mass regression combined with fibrosis on HE staining, degree of necrosis and quantity of remaining tumor cells. The relative IGF-1R expression was evaluated for association with tumor radiosensitivity. RESULTS: Immunohistochemistry showed diffuse IGF-1R staining on rectal cancer cells with various degrees of signal density. IGF-1R expression was significantly correlated with cTNM staging (P = 0.012) while no significant association was observed with age, sex, tumor size and degree of differentiation (P = 0.424, 0.969, 0.604, 0.642). According to the Rectal Cancer Regression Grades (RCRG), there were 31 cases of RCRG1 (radiation sensitive), 28 cases of RCRG2 and 28 cases of RCRG3 (radiation resistance) in 87 rectal cancer subjects. IGF-1R protein hyper-expression was significantly correlated with a poor response to radiotherapy (P < 0.001, r = 0.401). RT-PCR results from pre-radiation biopsy specimens also showed that IGF-1R mRNA negative group exhibited a higher radiation sensitivity (P < 0.001, r = 0.497). Compared with the pre-radiation biopsy specimens, the paired post-operative specimens showed a significantly increased IGF-1R protein and mRNA expression in the residual cancer cells (P < 0.001, respectively). CONCLUSION: IGF-1R expression level may serve as a predictive biomarker for radiosensitivity of rectal cancer before preoperative radiotherapy.