Linear, Planar, Orbicular, and Macrocyclic Multinuclear Zinc (Meth)acrylate Complexes.

Zinc carboxylate complexes are widely utilized as artificial models of metalloenzymes and as secondary building units of PCPs/MOFs. However, the relationship between the structure of the monodentate carboxylato ligand and the molecular arrangement of multinuclear zinc carboxylate complexes is not fully understood because of the coordination flexibility of the Zn ion and carboxylato ligands. Herein, we report the structural analysis of a series of complexes derived from zinc (meth)acrylate which has a linear infinite chain structure. The molecular structure of µ4-oxido-bridged tetranuclear complexes [Zn4(µ4-O)(OCOR)6] revealed a distorted Zn4O core. Crystallization of zinc acrylate under aqueous conditions afforded a µ3-hydroxido-containing pentanuclear complex [Zn5(µ3-OH)2(OCOR)8] as the repeating unit of an infinite sheet-like structure in the solid state. It was also obtained by the hydrolysis of the µ4-oxido-bridged tetranuclear complex. In sharp contrast, the methacrylate analog retained the methacrylato ligands under aqueous crystallization conditions to form a macrocyclic dodecanuclear complex with methacrylato as the sole ligand.

Suctionable Gauze Ball Operated by the Console Surgeon Overcomes Wet Scenes during Robotic Rectal Surgery.

Although robotic rectal resections are now widely performed, there are few robotic suction tools that can be easily used by console surgeons. It can therefore be difficult to maintain a clear visual field in the pelvis when there is effusion and bleeding from either a highly advanced cancer or from preoperative cancer treatment. In this report, we introduce our unique surgical technique that uses a soft catheter with a small gauze ball attached, inserted through the assistant port. This simple and inexpensive "instrument" can be used by the console surgeon as a retractor as well as a reliable suction device to secure their view of the operative field in the pelvis. This technique can be used in a narrow surgical field and does not rely on an assistant surgeon, making it potentially applicable to all types of surgery.

"Role-sharing surgery": a new surgical education system that gives beginner surgeons more chances to operate while ensuring the surgical quality of robotic surgery.

It has been pointed out that robotic surgery is more time-consuming than laparoscopic surgery, and a major challenge for the future is educating young surgeons while maintaining the surgical quality. To solve these problems, we report a role-sharing surgery (RSS) approach in which the surgery is divided into several areas and timetabled, with roles shared by several operators. We performed RSS for 19 standard colorectal cancer surgeries. The surgery was completed within + 28 min of the scheduled operation time, and a beginner robotic surgeon (BRS) was able to perform approximately 66% of the total surgery. There were no statistically significant differences in the short-term outcomes between the RSS and conventional surgery groups. Based on these findings, RSS has the potential to be the best practice for educating BRSs in robotic surgery, the use of which is expected to increase steadily in the future.

Spontaneous regression of advanced transverse colon cancer with deficient mismatch repair: a case report.

BACKGROUND: Spontaneous regression (SR) of cancer occurs in 1 in 60,000-100,000 patients. This phenomenon has been reported in almost all cancer types, most commonly neuroblastoma, renal cell carcinoma, malignant melanoma, and lymphoma/leukemia. However, SR in colorectal cancer (CRC) is extremely rare, particularly in advanced cases. Hence, this report describes a very rare case of spontaneous regression of advanced transverse colon cancer. CASE PRESENTATION: A 76-year-old female with anemia was diagnosed with a type II well-differentiated adenocarcinoma in the middle transverse colon. Two months later, a second colonoscopy examination was performed for preoperative marking, and it revealed tumor shrinkage and a shift to type 0-IIc morphology. Endoscopic tattooing was then performed, followed by a laparoscopic partial resection of the transverse colon with D3 lymph node dissection. However, the resected specimen contained no tumor, and colonoscopy showed no tumor remnants in the remaining colon. Histopathological examination revealed mucosal regeneration and a mucus nodule in between the submucosal and muscular layers, with no cancer cells detected. Immunohistochemical analysis revealed the loss of MutL homolog 1 (MLH1) and postmeiotic segregation increased 2 (PMS2) expression in the cancer cells of biopsied specimens, suggesting deficient mismatch repair (dMMR). The patient continues to be followed up until 6 years postoperatively, and no recurrence has been observed. In this study, we also reviewed similar reported cases of spontaneous regression of cancer involving dMMR. CONCLUSION: This study presents a rare case of spontaneous regression of advanced transverse colon cancer wherein dMMR is strongly involved. However, further accumulation of similar cases is needed to elucidate this phenomenon and to develop new treatment strategies for CRC.

Elevated Preoperative Serum Vascular Endothelial Growth Factor Does Not Predict Poor Outcomes in Curatively Resected Non-metastatic Colorectal Cancer Treated Without Neoadjuvant Therapy.

BACKGROUND/AIM: Vascular endothelial growth factor (VEGF) influences colorectal cancer (CRC) progression and is a key target in the treatment for metastatic CRC. However, the oncological impact of preoperative circulating VEGF in non-metastatic CRC (non-mCRC) has not been clearly elucidated. Herein, we have investigated the prognostic significance of elevated preoperative serum VEGF concentration in curatively resected non-mCRC without neoadjuvant therapy. PATIENTS AND METHODS: A total of 474 patients with pStage I-III CRC who underwent curative resection without neoadjuvant therapy were included. The relationship between preoperative serum VEGF concentration and clinicopathologic characteristics, overall survival (OS), and recurrence-free survival (RFS) were investigated. RESULTS: The median follow-up duration was 47.4 months. No significant relationship between preoperative VEGF and clinicopathologic characteristics including tumor markers, pStage, and lymphovascular invasion was identified; however, VEGF values were wide-ranged in every pStage. Patients were categorized into four groups as follows: VEGF < median, median to 75th percentile, 75th percentile to 90th percentile, and ≥90th percentile. A tendency for a difference in 5-year OS (p=0.064) and RFS (p=0.089) was observed among the groups; however, OS and RFS were not correlated with VEGF elevation. In multivariate analyses, VEGF ≥90th percentile was paradoxically associated with better RFS. CONCLUSION: Preoperative elevated serum VEGF concentration was associated with neither worse clinicopathological characteristics nor worse long-term outcomes in curatively resected non-mCRC. The prognostic value of preoperative circulating VEGF in initially resectable non-mCRC remains limited.

AZD6738 promotes the tumor suppressive effects of trifluridine in colorectal cancer cells.

Ataxia telangiectasia and Rad3­related (ATR) is a kinase that repairs DNA damage. Although inhibitors that selectively target ATR have been developed, their effectiveness in colorectal cancer has not been widely reported. The present study hypothesized that anticancer agents that effectively act in the S phase before the G2/M checkpoint may be ideal agents for concomitant use with ATR inhibitors, which act at the G2/M checkpoint. Therefore, the present study examined the combined effects of AZD6738, an ATR inhibitor, and trifluridine (FTD), which acts in the S phase and has a high DNA uptake rate. In vitro cell viability assays, flow cytometry and western blotting were performed to evaluate cell viability, and changes in cell cycle localization and protein expression. The results revealed that in colorectal cancer cells, the combination of AZD6738 and FTD inhibited cell viability, cell cycle arrest at the G2/M checkpoint and Chk1 phosphorylation, and increased apoptotic protein expression levels more than that when treated with FTD alone. HT29, a BRAF­mutant cell line known to be resistant to anticancer drugs, was used to induce tumors in vivo. Since FTD does not have sufficient efficacy when administered orally, it was mixed with tipiracil to prevent degradation; this mixture is known as TAS­102. TAS­102 alone exerted minimal tumor suppressive effects; however, when used in combination with AZD6738, tumor suppression was observed, suggesting that AZD6738 may increase the effectiveness of a weakly effective drug. Although ATR inhibitors are effective against p53 mutants, the present study demonstrated that these inhibitors were also effective against the p53 wild­type HCT116 colorectal cancer cell line. In conclusion, combination therapy with AZD6738 and FTD enhanced the inhibition of tumor proliferation in vitro and in vivo. In the future, we aim to investigate the potentiating effect of AZD6738 on 5­fluouracil­resistant cell lines that are difficult to treat.

Incomplete lymphatic sealing around the inferior mesenteric artery is a risk factor for chylous ascites in robotic rectal cancer surgery.

INTRODUCTION: Compared with laparoscopic surgery (LS), robotic surgery (RS) is considered to have acceptable outcomes in rectal cancer, but few reports have focused on chylous ascites in RS. The aim of this study was to investigate the incidence and etiology of chylous ascites after RS. METHODS: This retrospective study included 291 patients with rectal cancer who underwent RS (n = 165) or LS (n = 126) with high ligation of the inferior mesenteric artery (IMA). Propensity score matching (PSM) was performed to compare the two groups. RESULTS: \Dissection around the IMA was achieved using ultrasonic coagulating shears in most LS cases, and monopolar scissors in most RS cases, sometimes using bipolar vessel sealing device or bipolar forceps. The incidence of chylous ascites was 12.2% in RS and 4.1% in LS after PSM (P = .037). When limited to the RS group, multivariate analysis identified absence of lymphatic sealing at the left side of the IMA and shorter operative time as independent risk factors for chylous ascites. Except for duration of drain placement, no outcomes differed significantly with or without chylous ascites. One patient with chylous ascites developed later infection and required antibiotic treatment. CONCLUSION: The incidence of chylous ascites is significantly higher in RS than in LS, and RS with incomplete lymphatic sealing around the IMA is a risk factor for chylous ascites in rectal cancer. Although outcomes for patients with chylous ascites were acceptable, adequate lymphatic sealing during dissection around the IMA is crucial to prevent chylous ascites in RS.

Cancer cell­induced tissue inhibitor of metalloproteinase­1 secretion by cancer­associated fibroblasts promotes cancer cell migration.

Cancer­associated fibroblasts (CAFs) are one of the major components of the cancer stroma in the tumor microenvironment. The interaction between cancer cells and CAFs (cancer­stromal interaction; CSI) promotes tumor progression, including metastasis. Recently, the tissue inhibitor of metalloproteinase­1 (TIMP­1) was reported to promote cancer cell migration and metastasis, which is contrary to its anticancer role as an inhibitor of matrix metalloproteinase. Moreover, CAF­derived TIMP­1 is reported to regulate CAF activity. In the present study, we investigated the effect of TIMP­1 on colon cancer cell migration in vitro. The TIMP­1 secretion levels from the CAFs and cancer cell lines were comparatively measured to determine the main source of TIMP­1. Furthermore, the effect of CSI on TIMP­1 secretion was investigated using the Transwell co­culture system. Cancer cell migration was evaluated using the wound­healing assay. The results demonstrated that TIMP­1 promoted the migration of LoVo cells, a colon cancer cell line, whereas TIMP­1 neutralization inhibited the enhanced migration. The TIMP­1 levels secreted from the cancer cells were approximately 10 times less than those secreted from the CAFs. TIMP­1 secretion was higher in CAFs co­cultured with cancer cells than in monocultured CAFs. Furthermore, the migration of LoVo cells increased upon co­culturing with the CAFs. TIMP­1 neutralization partially inhibited this enhanced migration. These results suggest that CAFs are the primary source of TIMP­1 and that the TIMP­1 production is enhanced through CSI in the tumor microenvironment, which promotes cancer cell migration.

Robot-assisted laparoscopic abdominoperineal resection with en bloc prostatectomy using the Retzius-sparing robot-assisted radical prostatectomy technique.

INTRODUCTION: The best surgical technique for rectal cancer invading the prostate remains controversial. Rectal resection with en bloc prostatectomy using a standard retropubic approach is an option but has disadvantages. We report a new surgical procedure applying Retzius-sparing robot-assisted radical prostatectomy. MATERIALS AND SURGICAL TECHNIQUE: First, the rectum was mobilized mainly at its dorsal side. Next, the prostate was separated from the bladder and urethra via the pouch of Douglas approach without opening the Retzius cavity, after which the surgical specimen was extracted through the perineal wound. Lateral pelvic lymph node dissection was performed after vesicourethral anastomosis. DISCUSSION: This new robotic procedure minimizes surgical trauma and preserves normal pelvic anatomy. Furthermore, this approach makes it easy to perform subsequent lateral pelvic lymph node dissection.

The Interaction Between Cancer-associated Fibroblasts and Cancer Cells Enhances Bcl-xL and Mcl-1 in Colorectal Cancer.

BACKGROUND/AIM: The acquisition of resistance to apoptosis is one of the biggest problems in colorectal cancer (CRC) treatment. This study aimed to elucidate the mechanisms of resistance to apoptosis with a focus on interleukin (IL)-6 produced by the interaction between cancer cells and cancer-associated fibroblasts (CAFs). MATERIALS AND METHODS: DLD-1 and HCT116 cell lines were treated with IL-6 and furthermore co-cultured with CAFs. The expression levels of Bcl-xL, Mcl-1 and phosphorylation of STAT3 were evaluated by western blotting. We also performed immunostaining for CRC specimens and evaluated the correlation between CAFs invasion and Bcl-xL/Mcl-1 expression. RESULTS: Both IL-6 and co-culturing enhanced Bcl-xL, Mcl-1 and the phosphorylation of STAT3. Immunohistochemistry showed a positive correlation between CAFs and Bcl-xL/Mcl-1. These results showed that the interaction between CAFs and cancer cells enhances Bcl-xL and Mcl-1 through the IL-6/STAT3 signaling pathway. CONCLUSION: Our findings provide new potential therapeutic targets and strategies for CRC treatment.

ATR inhibitor AZD6738 increases the sensitivity of colorectal cancer cells to 5­fluorouracil by inhibiting repair of DNA damage.

The repair of DNA damage caused by chemotherapy in cancer cells occurs mainly at two cell cycle checkpoints (G1 and G2) and is a factor contributing to chemoresistance. Most colorectal cancers harbor mutations in p53, the main pathway involved in the G1 checkpoint, and thus, are particularly dependent on the G2 checkpoint for DNA repair. The present study examined the effect of AZD6738, a specific inhibitor of ataxia telangiectasia mutated and rad3­related (ATR) involved in the G2 checkpoint, combined with 5­fluorouracil (5­FU), a central chemotherapeutic agent, on colorectal cancer cells. Since 5­FU has a DNA­damaging effect, its combination with AZD6738 is likely to enhance the therapeutic effect. The effects of the AZD6738/5­FU combination were evaluated in various colorectal cancer cells (HT29, SW480, HCT116 and DLD­1 cells) by flow cytometry (HT29 cells), western blotting (HT29 cells) and water­soluble tetrazolium 1 assays (HT29, SW480, HCT116 and DLD­1 cells), as well as in an experimental animal model (HT29 cells). In vitro, the AZD6738/5­FU combination increased the number of mitotic cells according to flow cytometry, decreased the checkpoint kinase 1 phosphorylation levels and increased cleaved caspase­3 and phosphorylated form of H2A.X variant histone levels according to western blotting, and decreased the proliferation rate of four colon cancer cell lines according to cell viability experiments. In vivo, xenografted colorectal cancer cells treated with the AZD6738/5­FU combination exhibited a marked decrease in proliferation compared with the 5­FU alone group. The present results suggested that AZD6738 enhanced the effect of 5­FU in p53­mutated colorectal cancer.

The expression of carcinoembryonic antigen mRNA in the lavage of the dissected area of the lateral lymph nodes influences the lateral recurrence of lower rectal cancer.

PURPOSE: To determine whether or not migrating cancer cells are present on the surgical plane after lateral lymph node dissection (LLND) for lower rectal cancer and related to lateral recurrence (LR), we evaluated the lavage of LLND areas by reverse-transcription polymerase chain reaction (RT-PCR) to check the expression of CEA mRNA in the residual cancer cells. METHODS: Thirty patients who underwent curative LLND were enrolled. Lavage was collected after LLND and subjected to RT-PCR to detect CEA mRNA. The median follow-up to check for recurrence was 31.4 months. RESULTS: CEA mRNA was detected in 9 of the 46 dissected areas. Based on the receiver operating characteristic curves, the cut-off value of PCR was set at 0.025. This cut-off point classified five patients into the high-expression group for CEA mRNA. During follow-up, LR developed in 1 of 40 low-expression areas of CEA mRNA and 3 of 6 high-expression areas. The LR rate was higher in the high-expression group than in the low-expression group (p = 0.015). A multivariate analysis showed that the high expression of CEA mRNA was likely an independent prognostic factor of LR. CONCLUSION: The expression of CEA mRNA in the lavage of LLND areas indicates the presence of residual cancer cells that cause LR.

The clinical impact of robot-assisted laparoscopic rectal cancer surgery associated with robot-assisted radical prostatectomy.

INTRODUCTION: Robot-assisted laparoscopic surgery has been performed in various fields, especially in the pelvic cavity. However, little is known about the utility of robot-assisted laparoscopic rectal cancer surgery associated with robot-assisted radical prostatectomy (RARP). We herein report the clinical impact of robot-assisted laparoscopic rectal cancer surgery associated with RARP. METHODS: We experienced five cases of robot-assisted laparoscopic rectal cancer surgery associated with RARP. One involved robot-assisted laparoscopic abdominoperineal resection with en bloc prostatectomy for T4b rectal cancer, and one involved robot-assisted laparoscopic intersphincteric resection combined with RARP for synchronous rectal and prostate cancer. The remaining three involved robot-assisted laparoscopic low anterior resection (RaLAR) after RARP. For robot-assisted laparoscopic rectal cancer surgery, the da Vinci Xi surgical system was used. RESULTS: We could perform planned robotic rectal cancer surgery in all cases. The median operation time was 529 min (373-793 min), and the median blood loss was 307 ml (32-1191 ml). No patients required any transfusion in the intra-operative or immediate peri-operative period. The circumferential resection margin was negative in all cases. There were no complications of grade ≥III according to the Clavien-Dindo classification and no conversions to conventional laparoscopic or open surgery. CONCLUSION: Robot-assisted laparoscopic surgery associated with RARP is feasible in patients with rectal cancer. The long-term surgical outcomes remain to be further evaluated.

Chitinase 3-like 1 secreted from cancer-associated fibroblasts promotes tumor angiogenesis via interleukin-8 secretion in colorectal cancer.

The cancer­stromal interaction has been demonstrated to promote tumor progression, and cancer-associated fibroblasts (CAFs), which are the main components of stromal cells, have attracted attention as novel treatment targets. Chitinase 3-like 1 (CHI3L1) is a chitinase-like protein, which affects cell proliferation and angiogenesis. However, the mechanisms through which cells secrete CHI3L1 and through which CHI3L1 mediates tumor progression in the cancer microenvironment are still unclear. Accordingly, the present study assessed the secretion of CHI3L1 in the microenvironment of colorectal cancer and evaluated how CHI3L1 affects tumor angiogenesis. CAFs and normal fibroblasts (NFs) established from colorectal cancer tissue, and human colon cancer cell lines were evaluated using immunostaining, cytokine antibody array, RNA interference, reverse transcription-quantitative PCR (RT-qPCR), ELISA, western blotting and angiogenesis assays. The expression and secretion of CHI3L1 in CAFs were stronger than those in NFs and colorectal cancer cell lines. In addition, interleukin-13 receptor α2 (IL-13Rα2), a receptor for CHI3L1, was not expressed in colorectal cancer cell lines, but was expressed in fibroblasts, particularly CAFs. Furthermore, the expression and secretion of IL-8 in CAFs was stronger than that in NFs and cancer cell lines, and recombinant CHI3L1 addition increased IL-8 expression in CAFs, whereas knockdown of CHI3L1 suppressed IL-8 expression. Furthermore, IL-13Rα2 knockdown suppressed the enhancement of IL-8 expression induced by CHI3L1 treatment in CAFs. For vascular endothelial growth factor-A (VEGFA), similar results to IL-8 were observed in an ELISA for comparison of secretion between CAFs and NFs and for changes in secretion after CHI3L1 treatment in CAFs; however, no significant differences were observed for changes in expression after CHI3L1 treatment or IL-13Rα2 knockdown in CAFs assessed using RT-qPCR assays. Angiogenesis assays revealed that tube formation in vascular endothelial cells was suppressed by conditioned medium from CAFs with the addition of human CHI3L1 neutralizing antibodies compared with control IgG, and also suppressed by conditioned medium from CAFs transfected with CHI3L1, IL-8 or VEGFA small interfering RNA compared with negative control small interfering RNA. Overall, the present findings indicated that CHI3L1 secreted from CAFs acted on CAFs to increase the secretion of IL-8, thereby affecting tumor angiogenesis in colorectal cancer.

Efficacy of intraoperative ICG fluorescence imaging evaluation for preventing anastomotic leakage after left-sided colon or rectal cancer surgery: a propensity score-matched analysis.

BACKGROUND: Intestinal perfusion at the anastomotic site is thought to be one of the most influential risk factors for postoperative anastomotic leakage (AL). We evaluated the efficacy of indocyanine green (ICG) fluorescence imaging at the stump of the proximal colon in left-sided colectomy or rectal resection in terms of decreasing the incidence of AL. METHODS: Prospectively collected data were retrospectively evaluated. Patients who underwent left-sided colectomy or rectal resection were enrolled (ICG group; n = 197), and patients who had undergone a similar procedure before the ICG group were enrolled from the charts as historical controls (HC group; n = 187). After ICG evaluation, anastomosis was performed where fluorescence was sufficient. The incidence of AL was compared between the ICG and HC groups. Propensity score (PS)-matched data were analyzed to clarify the risk of AL. RESULTS: AL occurred in 6 patients (3.3%) in the ICG group and 17 (10.7%) in the HC group. ICG evaluation revealed 179 patients with good fluorescence and 18 with poor/none perfusion (9.1%). The transection line was changed in all patients with poor/none fluorescence. Three of these 18 patients developed AL (16.7%), though transection line was changed at which is thought to be good. We hope AL in poor/none fluorescence can be prevented at the same rate of cases with good fluorescence. Actually, the rate of that was significantly higher compared with good fluorescence patients (P = 0.038). 93 patients in each group were compared by PS-matched data analysis, which showed the AL rate in the ICG group was significantly lower than that in the HC group (3.2% vs 10.8%, respectively; P = 0.046). CONCLUSIONS: Even though this study has limitations of comparison of data prospectively collected and retrospectively analyzed, intraoperative ICG fluorescence imaging evaluation could significantly decrease the incidence of AL.

Accurate localization of rectal cancer using near infrared ray-guided surgery with intra-operative colonoscopy and da Vinci Firefly technology.

Accurate localization of the tumor during robot-assisted laparoscopic surgery for rectal cancer is crucial. Several techniques have been described, but each has its shortcomings. We developed a new technique of near infrared ray-guided surgery (NIRGS) to localize the tumor accurately, using intra-operative colonoscopy and da Vinci Firefly technology. After clamping the oral side of the tumor, the colonoscope was inserted. In the normal visible light mode, we could not recognize the endoscopic light; however, after changing to the Firefly mode, the endoscopic light was seen clearly. Using this simple and new technique, we could locate the tumor easily and accurately. We performed this technique in 12 patients and detected the location of the tumor clearly in all, without any procedure-related complications. Based on these findings, NIRGS is a useful and safe technique for detecting tumor location during robot-assisted laparoscopic surgery for rectal cancer.

[Review of High-Risk Factors and Adjuvant Chemotherapy Indication in T4-pStage â ¡ Colon Cancer].

BACKGROUND: T4 is one of the high-risk factors, but the efficacy of adjuvant chemotherapy for T4-Stage Ⅱ colon cancer are unclear. METHOD: We retrospectively reviewed 211 patients with primary pStage Ⅱ colon cancer who underwent radical resection between 2004 and 2015. RESULTS: The 5-year overall survival rate(OS)of Stage ⅡA/ⅡB/ⅡC were 90.2/83.4/ 59.2%, and the 5-year recurrence-free survival rate(RFS)were 87.3/73.3/42.8%. Multivariate analysis of OS as a high-risk factor of T4 revealed male, ly2/3, no adjuvant chemotherapy, and in RFS, male, ly2/3. However, compared the cases with or without adjuvant chemotherapy, 5-year OS was no difference. There were no cases used oxaliplatin-based adjuvant chemotherapy. CONCLUSION: An adjuvant chemotherapy without oxaliplatin were not enough to improve the prognoses of T4-Stage Ⅱcolon cancer, so the oxaliplatin based regimen might be recommended.

Eicosapentaenoic acid suppresses angiogenesis via reducing secretion of IL­6 and VEGF from colon cancer­associated fibroblasts.

Eicosapentaenoic acid (EPA) improves interleukin (IL)­6 hypercytokinemia in patients with advanced cancer due to its anti­inflammatory effects. This EPA mechanism has been revealed to lead to several anticancer effects. While the effects of EPA on cancer cells have been investigated, particularly in terms of angiogenesis, its effects on the tumor stroma remain unclear. In the present study, the authors clarified the role of EPA in cancer angiogenesis against colon cancer­associated fibroblasts (CAFs) from the colon stroma. With established human CAFs and normal fibroblasts from colon stroma (NFs), the authors evaluated IL­6 and vascular endothelial growth factor (VEGF) secretion with or without EPA treatment using ELISA. The signal inhibition of mitogen­activated protein kinase (ERK) in CAFs by EPA was evaluated using western blotting. In vitro anti­angiogenesis effects were evaluated by the angiogenesis assay on Matrigel using human umbilical vein endothelial cells (HUVECs) cultured with the supernatant obtained from CAF cultures with or without EPA. IL­6 secretion was greater from CAFs compared with that from NFs and stimulation with lipopolysaccharide (LPS) resulted in greater IL­6 secretion from the two fibroblast types compared with that from fibroblasts without LPS stimulation. While LPS stimulation increased VEGF secretion from the two fibroblast types, EPA decreased IL­6 and VEGF secretion from CAFs. Western blotting revealed that the addition of 30 µM EPA inhibited the ERK phosphorylation signal in CAFs. Furthermore, the angiogenesis assay with Matrigel revealed that the CAF culture supernatants treated with EPA suppressed tubular formation in HUVECs. These reductions may have been caused by the inhibition of ERK phosphorylation by EPA. Thus, EPA reduces cancer angiogenesis associated with CAFs. Additional studies will be needed to clarify the continuous anti­angiogenetic effect of chemotherapy using angiogenesis inhibitors (e.g. bevacizumab and aflibercept) in conjunction with or without EPA, and the clinical usage of EPA in conjunction with chemotherapy in vivo.

Laparoscopic extraperitoneal sigmoid colostomy using the totally extraperitoneal hernia repair technique after abdominoperineal resection for rectal cancer.

Stoma creation through the extraperitoneal route reportedly reduces the risk of parastomal hernia and stomal prolapse after abdominoperineal resection (APR) for rectal cancer. We describe a new technique for laparoscopic extraperitoneal sigmoid colostomy following APR. After the rectus abdominis muscle is separated, Lap ProtectorTM and EZ AccessTM devices are placed. An extraperitoneal stoma tunnel is created laparoscopically as much as possible. Next, the peritoneum is separated from the inside of the abdominal cavity, and the extraperitoneal tunnel is opened. At the time of writing, we had performed laparoscopic extraperitoneal sigmoid colostomy in eight patients, without any complications or conversion to the conventional procedure. Thus, laparoscopic extraperitoneal sigmoid colostomy is a useful and safe technique for the laparoscopic creation of an extraperitoneal stoma tunnel after APR.