TU-100 exerts a protective effect against bacterial translocation by maintaining the tight junction.

PURPOSE: We previously reported that TU-100 suppresses irinotecan hydrochloride (CPT-11)-induced inflammatory cytokines and apoptosis. However, the mechanism underlying this effect has not been fully elucidated. The aim of this study was to further clarify the mechanism of CPT-11-induced bacterial translocation (BT) and the effect of TU-100 on BT. METHODS: Cell cytotoxicity was assessed in vitro by a WST-8 assay. For the in vivo experiments, rats were randomly divided into 3 groups: the control group, the CPT-11 group (250 mg/kg i.p. for 2 days), and the CPT-11 and TU-100 co-treated group (1000 mg/kg, p.o. for 5 days). All of the rats were sacrificed on day 6 and their tissues were collected. RESULTS: CPT-11 and TU-100 co-treatment improved CPT-11 the related cytotoxicity in vitro. All CPT-11-treated rats developed different grades of diarrhea and BT was observed in 80% of the rats. CPT-11 caused a significant increase in the expression of TLR4, IL-6, TNF-α, IL-1ß and caspase-3 mRNAs in the large intestine. The expression of tight junction (TJ) marker mRNAs (occludin, claudin-1 and 4, and ZO-1) was significantly decreased in comparison to the control group. TU-100 co-treatment significantly reversed diarrhea, BT, and the expression of TLR2, IL-6, TNF-α, IL-1ß and caspase-3, and improved the expression of occludin, claudin-4 and ZO-1. CONCLUSIONS: TU-100 can suppress the adverse effects associated with CPT-11 and improve the function of the TJ. It is possible that this occurs through the TLR pathway.

The relationship of CD133, histone deacetylase 1 and thrombospondin-1 in gastric cancer.

BACKGROUND/AIM: Gastric cancer is one of the most common types of cancer. Cancer stem cells (CSCs) have been reported to play important roles in multiple cancer types. This study investigated the correlation between cluster of differentiation 133 (CD133), histone deacetylase 1 (HDAC1) and thrombospondin-1 (THBS1) expression in advanced gastric cancer. MATERIALS AND METHODS: The study included 65 patients with gastric cancer with recurrence after surgery. Expression of CD133, HDAC1 and THBS1 was examined by immunohistochemistry. Prognostic factors were investigated by multivariate analysis using Cox's proportional hazard model. RESULTS: Clinicopathological variables, including survival, of patients positive for CD133 expression (n=6, 23%), were compared with those without CD133 expression (n=20, 77%). Positive HDAC1 expression and THBS1 expression were observed in 34 (52%) and 17 (26%) patients, respectively. Using univariate analysis, positive expression of CD133 and negative expression of THBS1 predicted significantly worse prognosis. Multivariate analysis revealed CD133-positive and THBS1-negative expression were independent prognostic indicators. CONCLUSION: CD133 expression and THBS1 expression were prognostic factors, and a negative relationship between HDAC and THBS1 was observed in advanced gastric cancer. These biomarkers may help determine postoperative treatment in patients with gastric cancer.

Risk Model for Distal Gastrectomy When Treating Gastric Cancer on the Basis of Data From 33,917 Japanese Patients Collected Using a Nationwide Web-based Data Entry System.

OBJECTIVE: To establish a risk model for distal gastrectomy in Japanese patients with gastric cancer. BACKGROUND: Risk stratification for distal gastrectomy in Japanese patients with gastric cancer improves surgical outcomes. METHODS: The National Clinical Database was constructed for risk determination in gastric cancer-related gastrectomy among Japanese individuals. Data from 33,917 gastric cancer cases (1737 hospitals) were used. The primary outcomes were 30-day and operative mortalities. Data were randomly assigned to risk model development (27,220 cases) and test validation (6697 cases) subsets. Stepwise selection was used for constructing 30-day and operative mortality logistic models. RESULTS: The 30-day, in-hospital, and operative mortality rates were 0.52%, 1.16%, and 1.2%, respectively. The morbidity was 18.3%. The 30-day and operative mortality models included 17 and 21 risk factors, respectively. Thirteen variables overlapped: age, need for total assistance in activities of daily living preoperatively or within 30 days after surgery, cerebrovascular disease history, more than 10% weight loss, uncontrolled ascites, American Society of Anesthesiologists score (≥ class 3), white blood cell count more than 12,000/µL or 11,000/µL, anemia (hemoglobin: males, <13.5 g/dL; females, <12.5 g/dL; or hematocrit: males, <37%; females <32%), serum albumin less than 3.5 or 3.8 g/dL, alkaline phosphatase more than 340 IU/L, serum creatinine more than 1.2 mg/dL, serum Na less than 135 mEq/L, and prothrombin time-international normalized ratio more than 1.25 or 1.1. The C-indices for the 30-day and operative mortalities were 0.785 (95% confidence interval, 0.705-0.865; P < 0.001) and 0.798 (95% confidence interval, 0.746-0.851; P < 0.001), respectively. CONCLUSIONS: The risk model developed using nationwide Japanese data on distal gastrectomy in gastric cancer can predict surgical outcomes.

Protein kinase Cι is a new prognostic factor in gastric cancer.

PURPOSES: Protein kinase Cι (PKCι) is an important oncogenic K-ras effector, and its expression is correlated with tumor angiogenesis. The role of PKCι in gastric cancer remains unclear. The aim of this study was to clarify the role of PKCι in gastric cancer. METHODS: Twenty-eight patients with gastric cancer who underwent gastrectomy were enrolled in this study. The expression of PKCι mRNA was determined, as were the clinicopathological factors. The patients were divided into PKCι high and low expression groups. The 5-year survival rate, ERK mRNA level and VEGF mRNA level were compared between the two groups. The prognostic factors were investigated by a multivariate analysis. RESULTS: High expression of PKCι was observed to be associated with a lack of differentiation, tumor invasion ≥muscularis propria≤, stage III and IV disease and peritoneal dissemination. The 5-year survival rate in the PKCι high group was lower than that in the PKCι low group. The multivariate analysis revealed that a high expression level of PKCι was an independent prognostic factor. The expression levels of ERK and VEGF in the PKCι high group were higher than those in the PKCι low group. CONCLUSION: Our results indicate that PKCι is correlated with tumor progression and angiogenesis. PKCι may be a new prognostic factor for gastric cancer.

Phase I trial of neoadjuvant preoperative chemotherapy with S-1, oxaliplatin, and bevacizumab plus radiation in patients with locally advanced rectal cancer.

BACKGROUND: This phase I study was performed to determine the maximum tolerated dose (MTD), recommended dose (RD), and dose-limiting toxicities (DLTs) of oxaliplatin combined with preoperative chemoradiotherapy with S-1, oxaliplatin, and bevacizumab in locally advanced rectal cancer. METHODS: Eligible patients had a newly diagnosed clinical stage T1-4 N0-3 M0 rectal adenocarcinoma within 12 cm of the anal verge suitable for curative resection. Conformal radiation therapy was given (4 fields, 2 Gy daily fractions, 5 days/week, total dose 40 Gy) with concurrent S-1 (80 mg/m(2)/day orally, days 1-5, 8-12, 15-19, and 22-26), bevacizumab (90 min continuous intravenous infusion at 5 mg/kg, days 1 and 15), and oxaliplatin (120 min continuous intravenous infusion, days 1, 8, 15, and 22). The initial oxaliplatin dose (40 mg/m(2)/day) was gradually increased to determine the MTD and RD. Surgery was performed 6 weeks after completion of preoperative chemoradiotherapy. RESULTS: 11 patients were enrolled. The MTD of oxaliplatin was considered to be 60 mg/m(2), because three of five patients developed DLTs such as diarrhea and hives. The recommended dose of oxaliplatin was set at 50 mg/m(2). Of the patients who received oxaliplatin at ≤ RD, 5 (83.3%) had a clinical response [four pathological responses and one pathological complete response (Grade 3)]. CONCLUSIONS: With this new regimen, the MTD of oxaliplatin was 60 mg/m(2), and the RD for phase II studies was 50 mg/m(2). This new regimen appears to provide worthwhile outcomes for locally advanced rectal cancer and merits a phase II study.

Duodenal-jejunal bypass improves diabetes and liver steatosis via enhanced glucagon-like peptide-1 elicited by bile acids.

BACKGROUND AND AIM: Bariatric surgery not only elicits weight loss but also rapidly resolves diabetes. However, the mechanisms remain unclear. The present study investigates how diabetes and liver steatosis are improved after duodenal-jejunal bypass (DJB) compared with a glucagon-like peptide-1 (GLP-1) analog and correlations between bile acids and GLP-1 secretion. METHODS: We initially determined the effects of bile acids on GLP-1 in vitro and then assigned 12 male 16-week-old Otsuka Long-Evans Tokushima Fatty rats to groups that underwent DJB, a sham operation, or were treated with the GLP-1 receptor agonist, liraglutide (n = 4 each). Blood glucose, insulin, GLP-1, serum bile acids, liver steatosis, and the number of GLP-1 positive cells (L cells) in the small intestine and colon were investigated in the three groups at eight weeks postoperatively. RESULTS: Levels of GLP-1mRNA were upregulated and GLP-1 secretion increased in cells incubated with bile acids in vitro. Weight gain was suppressed more in the DJB than in the sham group in vivo. Diabetes was more improved and GLP-1 levels were significantly higher in the DJB than in the sham group. Serum bile acids were significantly increased, the number of L cells in the ileum was upregulated compared with the sham group, and liver steatosis was significantly improved in the DJB compared with the other two groups. CONCLUSIONS: Duodenal-jejunal bypass might improve diabetes and liver steatosis by enhancing GLP-1 secretion through increasing serum bile acids and the proliferation of L cells in the ileum, compared with liraglutide.

CD133 expression is correlated with poor prognosis in colorectal cancer.

BACKGROUND/AIMS: Cancer stem cells (CSC) was reported to play an important role in various kinds of cancer. CD133 is one of the cancer stem cell markers in solid cancers. However, the correlation between CD133 expression and the clinicopathological factors in colorectal cancer (CRC) remains unclear. METHODOLOGY: Forty patients with CRC who underwent operations were enrolled. Expression of CD133 was investigated by immunohistochemistry (IHC). The staining was observed in the cytoplasm of cancer cells and the patients who have the staining were defined as CD133-positive cases. The patients were divided into two groups: the CD133-positive group (n = 22) and negative group (n = 18). Clinicopathological factors were compared between the two groups. The prognostic factors were investigated by multivariate analysis. RESULTS: In the CD133-positive group, the incidence of lymph node and liver metastasis, lymphatic and venous invasion, as well as the progression of stage of cancer were higher than that in the CD133-negative group. The 5-year survival rate and the disease-free survival rate in the CD133-positive group were lower than that in the CD133-negative group. The multivariate analysis revealed that CD133 expression tended to be an independent prognostic factor. CONCLUSIONS: CD133 expression is correlated with poor prognosis in CRC.

Cyclopamine decreased the expression of Sonic Hedgehog and its downstream genes in colon cancer stem cells.

UNLABELLED: Backround: Most solid cancers including colon cancer are believed to be initiated from and maintained by cancer stem cells (CSCs), that are responsible for treatment resistance, resulting in tumor relapse. The aim of this study was to clarify the possible role of the Sonic Hedgehog (Shh) signaling pathway in the regulation of cancer stem cells. MATERIALS AND METHODS: The HCT-116 cell line was cultured with fetal bovine serum in RPMI-1640 medium and its sphere was grown in serum-free non-adherent culture. Gene expressions were analyzed by quantitative real-time polymerase chain reaction (qRT-PCR) from cells treated with and without cyclopamine. RESULTS: HCT-116 sphere-derived cells grown in serum-free, non-adherent culture, showed significantly increased expression of stem cell markers, Shh downstream genes and epithelial-mesenchymal transition (EMT) markers compared to parental cells grown in conventional culture. The expression of stemness markers, Shh downstream genes and EMT markers were higher in cancer spheres than the parental cell line and down-regulated by cyclopamine treatment in a dose-dependent manner. CONCLUSION: Overall, these findings show that cyclopamine treatment could down-regulate the expression of stemness markers, shh downstream genes and EMT markers on HCT-116 spheres.

Effect of light irradiation by light emitting diode on colon cancer cells.

BACKGROUND/AIM: Recent studies have demonstrated the efficacy of irradiation from light emitting diodes (LED) for wound healing, anti-inflammation and anticancer therapies. However, little is known about the effects of visible light in colon cancer cells. The purpose of this study was to evaluate the biological response (including gene expression changes) of human colon cancer cells to different wavelengths of LED irradiation. MATERIALS AND METHODS: Human colon cancer cells (HT29 or HCT116) were seeded onto laboratory dishes that were then put on LED irradiation equipment with a 465 nm-, 525 nm-, or 635 nm-LED. Irradiation at 15 or 30 mW was performed 10 min/day, each day for 5 days. The cell counting kit8 was then used to measure cell viability. Apoptosis and expression of several mRNAs (caspase, MAPK and autophagy pathway) in HT29 cultures irradiated with 465 nm LED were evaluated via AnnexinV/PI and RT-PCR, respectively. RESULTS: Viability of HT29 and HCT116 cells was lower in 465 nm-LED irradiated cultures than in control cultures, but viability of HT29 cells did not differ between control cultures and 525 nm-LED or 635 nm-LED irradiated cultures. Moreover, the expression of FAS, caspase-3, capase-8, and JUK were significantly higher in 465 nm-LED irradiated cultures than in control cultures, and expression of ERK1/2 and LC3 was lower in blue-irradiated cells. CONCLUSION: LED irradiation at 465 nm inhibited the proliferation of HT29 cells and of HCT116 cells. Notably, LED irradiation at 465 nm promoted apoptosis inHT29 cultures via the extrinsic apoptosis pathway and the MAPK pathway.

Hybrid technique for laparoscopic incisional ventral hernia repair combining laparoscopic primary closure and mesh repair.

INTRODUCTION: Incisional ventral hernia is one of the most common surgical complications after laparotomy. Laparoscopic repair of incisional ventral hernia has been conducted recently, and the advantages of this procedure have been reported. However, in large orifice cases, the recurrence rate is increased. To improve recurrence rates in large cases, a hybrid method combining laparoscopic primary closure and mesh repair can be applied. MATERIALS AND SURGICAL TECHNIQUE: Monofilament thread was inserted into the abdominal cavity for hernia closure and pulled from the other side of the orifice. The same procedure was performed from the upper side to the lower side without closure, and all thread was placed in line. Both sides of the thread were then introduced to the midline of the incision through a subcutaneous route. This procedure was conducted with an introducer. All threads were tied, and then a mesh was placed. DISCUSSION: Hybrid techniques already combine mini-laparotomy for hernia closure and subsequent laparoscopic intraoperative onlay mesh for reinforcement, but such techniques require laparotomy. In our technique, closure of the linea alba does not require laparotomy. All procedures were performed laparoscopically. This procedure is very easy and safe, and does not require the abdominal cavity to be opened. Thus, hybrid methods are effective for treating cases of incisional hernia involving a large orifice.

Expression of Stathmin1 in gastric adenocarcinoma.

BACKGROUND: Over expression of Stathmin1 (STMN1), activation-induced cytidine deaminase (AID) and protein kinase C iota (PKCi) proteins participate in the regulation of carcinogenesis. In the present study, we investigated the expression of STMN1 in patients with gastric adenocarcinoma and also determined the correlation of STMN1 with AID and PKCi proteins. MATERIALS AND METHODS: This study was conducted in the Tokushima University Hospital between September 2009 and September 2010 on a total of 59 patients with gastric adenocarcinoma. Stathmin1, AID and PKCi protein expressions were evaluated by immuno-histochemistry in gastric adenocarcinoma. RESULTS: A strong expression of STMN1 was significantly associated with gender- and poorly differentiated gastric adenocarcinoma (p<0.05). A high mRNA level of STMN1 was found in the tumor tissue of gastric adenocarcinoma compared to non-tumor tissue (p<0.05). In addition, STMN1 expression was significantly correlated with AID and PKCi protein expressions in gastric adenocarcinoma (p<0.05). CONCLUSION: High mRNA level of the Stathmin1 gene was significantly expressed in gastric tumor tissue than non-tumor and strong expression of STMN1 protein is correlated with poorly-differentiated gastric adenocarcinoma.

Comparisons of inflammatory cytokines expressions in drain after laparoscopic versus open surgery.

BACKGROUND/AIMS: Laparoscopic surgery reduces the risk of postoperative adhesion compared with open surgery. The aim of this study was to assess the advantage of laparoscopic surgery in terms of postoperative adhesion. METHODOLOGY: Eleven patients participated in this study (laparoscopic surgery: 6 patients, open surgery: 5 patients). Body temperature, heart rate, the duration until the first postoperative flatus and the beginning of diet were investigated on postoperative day 0, 1, 3, and 5, respectively. Serum level of WBC and CRP, PAI-1 and IFN-gamma level in the drainage tube were also measured at the same time. RESULTS: There is no significant difference between the two groups in body temperature. The laparoscopic group revealed significantly lower WBC on POD 0 and CRP on POD 1 compared with the open group. PAI-1 was significantly lower on POD 3 and 5 in the laparoscopic group. IFN-gamma in the laparoscopic group tended to be suppressed compared with the open group. CONCLUSIONS: Laparoscopic surgery may decrease the risk of postoperative abdominal adhesion compared with open surgery by suppressing early postoperative inflammation.

The role of activation-induced cytidine deaminase expression in gastric adenocarcinoma.

BACKGROUND: Gastric adenocarcinoma is one of the most common malignant tumors and the leading cause of malignancy-related death worldwide. Studies have reported overexpression of activation-induced cytidine deaminase (AID) and protein kinase c iota (PKCi) proteins showing involvement in the regulation of carcinogenesis. In the present study, we investigated the expression of AID and PKCi in patients with gastric adenocarcinoma and determined the correlation between these proteins. MATERIALS AND METHODS: This study was conducted between September 2009 and September 2010 on a total of 59 patients with gastric adenocarcinoma at the Tokushima University Hospital. AID, PKCi and mutated p53 protein expressions were evaluated by immunohistochemistry in gastric adenocarcinoma. RESULTS: High AID and PKCi expression was significantly (p<0.05) associated with poorly-differentiated gastric adenocarcinoma. In addition, PKCi expression was significantly correlated with clinicopathological findings such as a lymph node metastasis, and venous and lymphatic invasion (p<0.05). Furthermore, AID expression was significantly correlated with PKCi and mutated p53 protein expression in gastric adenocarcinoma (p<0.05). CONCLUSION: High AID and PKCi expressions were significantly correlated with poorly-differentiated gastric adenocarcinoma.

Characteristics of internal hernia after gastrectomy with Roux-en-Y reconstruction for gastric cancer.

BACKGROUND: Although the internal hernias have been a huge topic in the field of bariatric surgery, there were a few reports in gastric cancer. The purpose of this study was to analyze the incidence, clinical features, and prevention of internal hernia after gastrectomy for gastric cancer. METHODS: Twelve patients who underwent surgical treatment for internal hernia in our hospital after gastrectomy were analyzed. Features, including incidence, symptoms, and signs, were investigated in detail. RESULTS: The operative procedures for preceding gastrectomies were open distal gastrectomy in three patients, open total gastrectomy in three patients, laparoscopic-assisted distal gastrectomy in two patients, and laparoscopic total gastrectomy in four patients. The most frequent sites of internal hernias were jejunojejunostomy mesenteric defects (five patients) and Petersen's defect (five patients), mesenterium of transverse colon (one patient), and esophagus hiatus (one patient). There was no significant difference between open and laparoscopic preceding gastrectomies. After closure of the mesenteric defect was introduced, no further internal hernias occurred. On CT examination, the whirl sign was present in ten patients on 3D images. CONCLUSIONS: The present data suggest the importance of early recognition and treatment of internal hernia, as well as its prevention by closure of mesenteric defects.

Benefits of simultaneous laparoscopic resection of primary colorectal cancer and liver metastases.

INTRODUCTION: Recently, consensus on the optimal strategy for resectable synchronous colorectal liver metastases (LM) seems to have shifted toward simultaneous resection. However, there are still relatively few reports about simultaneous laparoscopic resection. The aim of this study is to evaluate the outcomes of patients who underwent simultaneous laparoscopic resection. METHODS: We evaluated 14 patients who underwent simultaneous resection of primary colorectal cancer and LM in our hospital from 2004 to 2012. Patients were selected by matched pair analysis based on the number of LM (≤4) and tumor size (≤5 cm). We divided them into two groups: the simultaneous laparoscopic resection of primary colorectal cancer and LM (Lap-S) group (n = 7) and the simultaneous open resection of primary colorectal cancer and LM (Open-S) group (n = 7). Clinical and oncologic outcomes were compared between the groups. RESULTS: The Lap-S patients were significantly older than the Open-S patients. The mean operative times of Lap-S and Open-S were 472 min and 466 min, respectively. The mean blood loss was significantly smaller in the Lap-S group (153 mL) than in the Open-S group (496 mL). There was no surgical mortality in either group. The incidence of postoperative complications in the Lap-S and Open-S groups was 12.3% and 33.0%, respectively. The mean postoperative hospital stay was significantly shorter in the Lap-S group (16 days) than in the Open-S group (36 days). There was no significant difference in long-term survival between the two groups. CONCLUSION: Lap-S patients had equivalent long-term outcomes to Open-S patients. Therefore, given its technical feasibility and safety, Lap-S may be one of the most promising options in selected patients.

The effect of polysaccharide k with S-1 based chemotherapy in advanced gastric cancer.

BACKGROUND/AIMS: Polysaccharide K (PSK) is widely used in Japan as a biological response modifier for cancer patients. We investigated the effects of PSK with S-1 based chemotherapy for advanced gastric cancer patients in immune response. METHODOLOGY: Nine advanced gastric cancer patients who underwent chemotherapy at the University of Tokushima were included in this study. In all patients, 3g PSK was received orally and S-1 based chemotherapy for 2 weeks alternately for 8 weeks. Serial changes in immunological parameters (Foxp3, Natural killer (NK), CD4/CD8) were monitored. RESULTS: The levels of Foxp3 at 8 weeks was significantly decreased compared with 2 weeks (4.26% vs. 3.11%). In NK activity at 8 weeks was significantly increased compared with 2 weeks (27% vs. 47%). CONCLUSIONS: These results of this study suggested that chemotherapy with PSK improved the immune response in advanced gastric cancer patients. Especially Foxp3 was concerned in this mechanism.

Impact of C-reactive protein on prognosis of patients with colorectal carcinoma.

BACKGROUND/AIMS: The aim of this study was to investigate the impact of preoperative serum C-reactive protein (CRP) level as a prognostic indicator in patients with colorectal carcinoma (CRC). METHODOLOGY: We investigated the correlation between preoperative CRP level and clinicopathological factors including prognosis of 167 patients who underwent resection for CRC retrospectively. Clinicopathological variables were compared between patients with serum CRP levels >1mg/dL (29 patients; high-CRP group) and patients with serum CRP levels <1mg/dL (138 patients; low-CRP group). RESULTS: In high-CRP group, 9 patients were stage I+II and 20 patients ware stage III+IV. In low-CRP group, 93 patients were stage I+II and 45 patients were stage III+IV. There were significant differences in the clinical stage, tumor diameter, curativity, final stage between the two groups (p<0.01). The overall survival and recurrence-free survival rates in high-CRP group were lower compared with the rates in low-CRP group (p<0.05 and p=0.14). In addition, the overall survival rate in stage I+II patients with high-CRP was significantly lower than that in patients with low-CRP (p<0.05). Using multivariate analysis, the preoperative elevation of serum CRP level was an independent prognostic factor in patients with CRC (p<0.05). CONCLUSIONS: We found that the preoperative elevation of serum CRP to be an independent prognostic indicator of CRC.

Efficacy of PET-CT for predicting the malignant potential of gastrointestinal stromal tumors.

PURPOSES: Gastrointestinal stromal tumor (GIST) is the most common sarcoma of the intestinal tract. The risk category is usually determined by tumor size and mitotic count, but accurate preoperative diagnosis of GIST is very difficult. The purpose of this study is to evaluate the efficacy of positron emission tomography (PET)-CT for predicting the malignant potential of gastrointestinal stromal tumors. METHODS: Ten patients with GIST who underwent a preoperative PET-CT examination were divided into two groups by risk category, and various factors were compared between the two groups. The relationships between the maximum standardized uptake value (SUVmax) and GIST parameters were examined. RESULTS: Patients were classified into two groups by their risk category: (low/intermediate-risk or high-risk). The SUVmax was significantly higher in the high-risk group (11.0 ± 3.04) than in the low/intermediate-risk group (2.1 ± 1.5). The Ki67 labeling index was also significantly higher in the high-risk group (8.63 ± 6.2) than in the low/intermediate-risk group (1.75 ± 0.52). There was a significant correlation between the Ki67 labeling index and the SUVmax (p = 0.028) and between the mitotic index and the SUVmax (p = 0.029). CONCLUSIONS: PET-CT can predict malignant potential. Cases with a SUVmax of over 5 may have malignant potential.

Survivin expression can predict the effect of chemoradiotherapy for advanced lower rectal cancer.

BACKGROUND: Chemoradiotherapy (CRT) has been used to improve local control and survival in patients with advanced rectal carcinoma. However, a significant proportion of patients show poor response to adjuvant CRT. We thus investigated the usefulness of survivin expression as a predictive marker of the CRT response and its characteristics. METHODS: Forty-three patients with lower rectal cancer who underwent CRT were investigated. All patients received preoperative CRT consisting of TS-1 concurrent with 40 Gy of pelvic irradiation followed by curative resection. The relationship between clinical response, or pathological response, and the expression of survivin of pre-CRT biopsy specimens was evaluated by immunohistochemistry and compared with post-CRT expression. RESULTS: Positive expression of survivin was observed in 26 of 43 patients (60%) in pre-CRT specimens. Survivin was positively expressed in 77% of stable disease cases, and 43% of partial response (p < 0.05). Regarding the correlation between pathological response and survivin expression, positive expression of survivin was recognized in 75% (18 of 24) of Grade 0 + 1 cases, 50% (7 of 14) of Grade 2 cases, and 20% (1 of 5) of Grade 3 cases. A reverse correlation was recognized between pathological responses and survivin expression (p < 0.05). There were differences in the tumor differentiation between the survivin-positive group and the negative group (p < 0.05). The expression concordance rate was 66% between pre- and post-CRT tissues. In post-CRT tissues, nuclear survivin expression disappeared completely and cytoplasmic expression increased, especially in responder cases. CONCLUSION: Survivin expression in biopsy could be an important predictive factor of preoperative CRT response.

microRNA expression is able to predict response to chemoradiotherapy in rectal cancer.

Although global microRNA (miRNA) expression patterns of several embryologic, physiological and oncogenic processes have been thoroughly studied, no studies are available on the role of miRNAs in pre-operative chemoradiotherapy (CRT) in rectal cancer. This study aimed to delineate the expression pattern of miRNAs for the prediction of response to CRT in rectal cancer. Rectal cancer patients (n=43), who underwent pre-operative CRT (40 Gy radiotherapy combined with S-1), were studied. RNA harvested from rectal cancer biopsy specimens prior to pre-operative CRT was hybridized to miRNA microarrays (821 genes). The response to CRT was evaluated by histopathological examination of surgically resected specimens, Response Evaluation Criteria in Solid Tumors (RECIST) and downstaging. The data of miRNA microarray were evaluated by real-time reverse transcription-polymerase chain reaction (RT-PCR). Two miRNAs (miR-142-3p, 223) with an increased expression that correctly differentiated responders from non-responders to CRT were identified by histopathological examination. One gene (miR-223) showed a higher, while 8 genes (miR-20b, miR-92a, let-7a*, miR-20a, miR-17*, miR-106a, miR-17 and miR-20a*) a lower expression in responders compared to nonresponders, with regard to RECIST. The 3 genes (miR-223, miR-630 and miR-126*) had a higher expression in responders compared to non-responders, with regard to downstaging. The real-time RT-PCR evaluation analysis detected a higher miR-223 level in responders compared to non-responders. Consequently, candidate miR-223 may be a new biomarker for the prediction of response to CRT and may be useful when establishing tailor-made therapies for rectal cancer.