Masahide Fukaya

Cross talk between hedgehog and epithelial–mesenchymal transition pathways in gastric pit cells and in diffuse-type gastric cancers

We previously reported hedgehog (Hh) signal activation in the mucus-secreting pit cell of the stomach and in diffuse-type gastric cancer (GC). Epithelial–mesenchymal transition (EMT) is known to be involved in tumour malignancy. However, little is known about whether and how both signallings cooperatively act in diffuse-type GC. By microarray and reverse transcription–PCR, we investigated the expression of those Hh and EMT signalling molecules in pit cells and in diffuse-type GCs. How both signallings act cooperatively in those cells was also investigated by the treatment of an Hh-signal inhibitor and siRNAs of Hh and EMT transcriptional key regulator genes on a mouse primary culture and on human GC cell lines. Pit cells and diffuse-type GCs co-expressed many Hh and EMT signalling genes. Mesenchymal-related genes (WNT5A, CDH2, PDGFRB, EDNRA, ROBO1, ROR2, and MEF2C) were found to be activated by an EMT regulator, SIP1/ZFHX1B/ZEB2, which was a target of a primary transcriptional regulator GLI1 in Hh signal. Furthermore, we identified two cancer-specific Hh targets, ELK1 and MSX2, which have an essential role in GC cell growth. These findings suggest that the gastric pit cell exhibits mesenchymal-like gene expression, and that diffuse-type GC maintains expression through the Hh–EMT pathway. Our proposed extensive Hh–EMT signal pathway has the potential to an understanding of diffuse-type GC and to the development of new drugs.

Hedgehog and epithelial-mesenchymal transition signaling in normal and malignant epithelial cells of the esophagus

It has been established that the Hedgehog (Hh) and epithelial‐mesenchymal transition (EMT) signals act on morphogenesis of embryonic and adult tissues. Recently, both signals have been involved in tumor malignancy. However, little is known as to whether Hh and EMT signals act on normal and malignant epithelial cells in the esophagus. By laser microdissection (LMD)‐based microarray and reverse transcription polymerase chain reaction in the undifferentiated and differentiated epithelial cells of the esophagus, we compared the expression profiles of Hh and EMT signaling molecules of these cells with those of cancers. Whether and how both signalings act in undifferentiated cells and in cancer cells are investigated by treatment of a Hh‐signal inhibitor and/or siRNAs of Hh and EMT transcriptional key regulator genes on a mouse primary culture and on human esophageal squamous cell carcinoma (ESCC) cell lines. Undifferentiated esophageal epithelial cells and most ESCCs coexpressed Hh and EMT signaling genes. Some mesenchymal‐related genes were regulated by an EMT regulator SIP1/ZEB2/ZFHX1B, which was a downstream gene of a primary transcriptional transducer GLI1 in Hh signaling. Hh signal block inhibited esophageal keratinocyte differentiation and cancer cell invasion and growth. These findings suggest that the mesenchymal gene expression of undifferentiated cells is maintained or strengthened in cancer cells through Hh signaling. This is a first report showing the presence of crosstalk between Hh and EMT pathways.

Clinicopathologic characteristics and survival of patients with clinical Stage I squamous cell carcinomas of the thoracic esophagus treated with three-field lymph node dissection.

OBJECTIVE Clinicopathologic characteristics and survival rates of patients with clinical Stage I tumors treated with three-field lymph node dissection have not been well investigated. This report documents the results of a series of cases of clinical Stage I squamous cell carcinomas treated with this surgical procedure in our institute. METHODS From January 1988 to March 1997, 326 patients with carcinomas of the thoracic esophagus underwent transthoracic esophagectomy with three-field lymph node dissection. Two hundred and ninety-seven (91%) of these had squamous cell carcinomas. Fifty-seven (18%) patients with clinical Stage I squamous cell carcinomas of the thoracic esophagus were retrospectively reviewed here. RESULTS Among 57 clinical Stage I squamous cell carcinomas, ten (18%) were diagnosed as T1-mucosal and 47 (83%) as T1-submucosal. Seventy percent of the patients with clinical T1-mucosal tumors had additional primary esophageal lesions. The operative morbidity and in-hospital mortality rates were 63 and 0%, and the overall 1-, 3-, 5-, and 10-year survival rates were 95, 86, 78, and 70%, respectively. Of the 57 tumors assessed pathologically, 12 (21%) were T1-mucosal, 42 (74%) were T1-submucosal, and three (5%) were T2. Nineteen (33%) exhibited lymph node metastasis. The 1-, 3-, 5-, and 10-year survival rates for patients with lymph node metastasis were 90, 79, 73, and 58%, respectively, as compared with 97, 90, 80, and 76, respectively for patients without lymph node metastasis (P=0.24). The accuracy of preoperative staging, based on both wall penetration and the status regarding lymph node metastasis, was 63%. With reference to the 1997 UICC-TNM staging system, 36 (63%) were pStage I, two (4%) were pStage IIA, 18 (28%) were pStage IIB, and three (6%) were pStage IVB. The 1-, 3-, 5-, and 10-year survival rates for patients with pStage I disease were 97, 92, 85, and 81%, respectively. In those with pStage II or IV disease, the values were 91, 76, 65, and 52%, respectively. CONCLUSIONS Three-field lymph node dissection may be indicated even for patients with clinical Stage I squamous cell carcinoma requiring surgical intervention because this surgical procedure provides for possible cure by removing unsuspected lymph node metastasis.

Randomized clinical trial of the effect of perioperative synbiotics versus no synbiotics on bacterial translocation after oesophagectomy

The impact of perioperative synbiotics on bacterial translocation and subsequent bacteraemia after oesophagectomy is unclear. This study investigated the effect of perioperative synbiotic administration on the incidence of bacterial translocation to mesenteric lymph nodes (MLNs) and the occurrence of postoperative bacteraemia.

The detection of intraoperative bacterial translocation in the mesenteric lymph nodes is useful in predicting patients at high risk for postoperative infectious complications after esophagectomy.

Objective:To investigate the incidence of BT in the mesenteric lymph node and bacteremia after an esophagectomy using a bacterium-specific ribosomal RNA-targeted reverse-transcriptase quantitative polymerase chain reaction (RT-qPCR). Background:There is little evidence regarding the occurrence of bacterial translocation (BT) and its correlation to postoperative infectious complications after an esophagectomy. Methods:Eighteen patients with esophageal cancer were studied. Mesenteric lymph nodes were harvested from the jejunal mesentery before surgical mobilization (MLN-1) and after the restoration of bowel continuity (MLN-2). Blood and sputum were also sampled before surgery (Blood-1 and Sputum-1) and on postoperative day 1 (Blood-2 and Sputum-2). Results:The detection rates of bacteria in the MLN-2 (56%) and Blood-2 (56%) were significantly higher than those in the MLN-1 (17%) and Blood-1 (22%), indicating that surgical stress induces BT. The detection rate was not different between Sputum-1 (80%) and Sputum-2 (78%). There was an 80% sequence homology between the RT-qPCR products in the MLN-2 and Blood-2, whereas the homology was only 20% between Blood-2 and Sputum-2. In the patients with positive bacteria in the MLN-2 sample, there was a greater incidence of postoperative infectious complications than in patients without bacteria in the MLN-2 sample (P = 0.04). The postoperative hospital stay was also longer (P = 0.037) for patients with positive bacteria in the MLN-2 sample. Conclusions:BT frequently occurs during esophagectomies, and postoperative bacteremia is likely to be gut-derived. Patients with positive bacteria in the MLN-2 sample should be carefully managed because these patients are more susceptible to postoperative infectious complications.

Low skeletal muscle density is associated with poor survival in patients who receive chemotherapy for metastatic gastric cancer

Low skeletal muscle density (SMD) and low skeletal muscle index (SMI) are associated with poor overall survival (OS) in patients with various types of cancer. We retrospectively studied SMD and SMI using computed tomographic (CT) scans in patients with gastric cancer receiving chemotherapy to evaluate its prognostic significance. SMD and SMI were obtained from CT-based analysis using Slice-O-Matic® medical imaging software in patients who received S-1 plus cisplatin chemotherapy for metastatic gastric cancer. The CT images taken within 1 month before starting chemotherapy were used. The cut-off values for determining low SMD [<33 Hounsfield units (HU) in obese and <41 HU in non-obese patients] and low SMI (<41 cm2/m2 in females, <43 cm2/m2 in non-obese males and <53 cm2/m2 in obese males) were referenced from a large population based study. The CT images of 53 patients were reviewed. The median SMD was 36.8 HU (range, 19.5-59.3 HU), and the median SMI was 39.8 cm2/m2 (range, 23.7-60.0 cm2/m2). Patients with low SMD had significantly shorter OS compared with patients having normal SMD (8.9 vs. 12.8 months, P=0.03). However, OS did not differ significantly between patients with low and normal SMI (11.1 and 14.3 months, P=0.18). Multivariate analyses confirmed that low SMD was an independent predictor of poor outcomes (P<0.01). SMD is an important prognosticator of survival in patients with metastatic gastric cancer receiving chemotherapy.

Comparison of gastroesophageal reflux in 100 patients with or without prior gastroesophageal surgery

Background and purposeThe role of duodenogastroesophageal reflux (DGER) in gastroesophageal reflux disease (GERD) remains controversial. Few studies of reflux have compared patients with an intact stomach to those without intact stomach after gastroesophageal surgery. This study aimed to investigate differences of the refluxate between patients with and without prior gastroesophageal surgery and to assess the role of DGER in GERD.MethodsOne hundred patients (34% with reflux symptoms) were divided into four groups: 23 with an intact stomach, and 27, 42, and 8 with esophagectomy followed by gastric tube reconstruction, distal gastrectomy, and total gastrectomy, respectively. Reflux symptoms were evaluated, and endoscopy and simultaneous 24-h monitoring of esophageal pH and bilirubin were performed.ResultsOf 44 patients with increased DGER but without increased acid reflux, three had severe reflux esophagitis and seven had Barrett’s esophagus. DGER was most frequent under weakly acidic conditions in the intact stomach, esophagectomy, and distal gastrectomy groups. Pure acid reflux and DGER at any pH were elevated in GERD patients with an intact stomach, while weakly acidic and alkaline DGER were elevated in GERD patients after gastrectomy. Esophagectomy patients had reflux with the combined characteristics of those in the intact stomach and gastrectomy groups. Weakly acidic or alkaline DGER was correlated with symptoms and esophageal mucosal changes in gastrectomy patients.ConclusionThe refluxate causing GERD differed between patients with and without prior gastroesophageal surgery. Weakly acidic or alkaline DGER may cause both symptoms and esophageal mucosal damage.

Retrocolic or Antecolic Roux-en-Y Reconstruction after Distal Gastrectomy: Which Is More Effective in the Prevention of Postoperative Gastroesophageal Reflux Disease.

Background: It is unclear which reconstructive route (retrocolic or antecolic) is more effective in preventing postoperative gastroesophageal reflux disease (GERD) in Roux-en-Y reconstruction following distal gastrectomy. Methods: Eighty-one eligible patients (retrocolic, n = 39; antecolic, n = 42) underwent endoscopies before surgery and 1 year after surgery to evaluate reflux esophagitis according to the Los Angeles classifications. The relative anatomical position of gastrojejunostomy to the cardia was measured by CT imaging. Results: The proportion of patients with reflux esophagitis was also significantly higher in the antecolic group than in the retrocolic group (38.1 vs. 10.3%, p = 0.005). Multivariate analysis revealed that antecolic reconstruction and body mass index (BMI) were independent risk factors for reflux esophagitis. The relative position of gastrojejunostomy to the cardia in the antecolic group was shifted to the left laterally (59.0 vs. 28.8 degree, p < 0.001) and ventrally (65.4 vs. 39.8 degree, p < 0.001) than in the retrocolic group. There was a positive correlation between BMI and left lateral and ventral shifts of gastrojejunostomy in the antecolic group. Conclusion: Retrocolic reconstruction may be superior to antecolic reconstruction in preventing postoperative GERD, especially in obese patients. The left lateral and ventral shifts of gastrojejunostomy after antecolic reconstruction may aggravate the occurrence of GERD.

Two-stage operation for synchronous triple primary cancer of the esophagus, stomach, and ampulla of Vater: report of a case

A 69-year-old man with jaundice was diagnosed with cancer of the ampulla of Vater by endoscopic retrograde cholangiopancreatography and abdominal computed tomography. A screening gastrointestinal endoscopy showed middle thoracic esophageal cancer and early gastric cancer on the anterior wall of the lower gastric body. We chose a two-stage operation for synchronous triple primary cancer of the esophagus, stomach, and ampulla of Vater, in order to safely perform the curative resection of these three cancers. The first-stage operation consisted of a right transthoracic subtotal esophagectomy with mediastinal and cervical lymph node dissection, an external esophagostomy in the neck, and a gastrostomy. Thirty-five days after the first surgery, a total gastrectomy with regional lymph node dissection, and a pancreatoduodenectomy with Child’s reconstruction were performed as the second-stage surgery. Esophageal reconstruction was achieved using the ileocolon via the percutaneous route without vascular anastomosis.

Rectal duplication cyst successfully treated by laparoscopic total mesorectal excision using the prolapsing technique

Congenital alimentary tract duplication is a rare disease. It most frequently occurs in the ileum, with the rectum being the rarest site. Herein, we report a 38‐year‐old woman who was referred to our hospital because of severe anal pain. On digital examination, a smooth, round, rubbery mass was palpable; it was located 5 cm from the anal verge in the posterior rectal wall. A CT scan demonstrated a 5‐cm cystic lesion located anterior to the sacrum that was displacing the rectum anteriorly. Spontaneous remission of the tumor was evident; however, after 5 months of follow‐up, the patient experienced the same severe anal pain. MRI demonstrated a recurrent cystic lesion. To prevent further complications and to confirm or deny malignancy, laparoscopic total mesorectal excision using the prolapsing technique was performed. Pathologically, the cystic lesion was diagnosed as a rectal duplication cyst. This is the first report of a rectal duplication cyst successfully treated by laparoscopic total mesorectal excision.