Toshiyuki Okuma

C-C chemokine receptor 2 (CCR2) deficiency improves bleomycin-induced pulmonary fibrosis by attenuation of both macrophage infiltration and production of macrophage-derived matrix metalloproteinases

Macrophage infiltration is implicated in various types of pulmonary fibrosis. One important pathogenetic process associated with pulmonary fibrosis is injury to basement membranes by matrix metalloproteinases (MMPs) that are produced mainly by macrophages. In this study, C‐C chemokine receptor 2‐deficient (CCR2−/−) mice were used to explore the relationship between macrophage infiltration and MMP activity in the pathogenesis of pulmonary fibrosis, using the bleomycin‐induced model of this disease process. CCR2 is the main (if not only) receptor for monocyte chemoattractant protein‐1/C‐C chemokine ligand 2 (MCP‐1/CCL2), which is a critical mediator of macrophage trafficking, and CCR2 −/− mice demonstrate defective macrophage migration. Pulmonary fibrosis was induced in CCR2−/− and wild‐type (CCR2+/+) mice by intratracheal instillation of bleomycin. No significant differences in the total protein concentration in bronchoalveolar lavage (BAL) fluid, or in the degree of histological lung inflammation, were observed in the two groups until day 7. Between days 3 and 21, however, BAL fluid from CCR2−/− mice contained fewer macrophages than BAL fluid from CCR2+/+ mice. Gelatin zymography of BAL fluid and in situ zymography revealed reduced gelatinolytic activity in CCR2−/− mice. Immunocytochemical staining showed weaker expression of MMP‐2 and MMP‐9 in macrophages in BAL fluid from CCR2−/− mice at day 3. Gelatin zymography of protein extracted from alveolar macrophages showed reduced gelatinolytic activity of MMP‐2 and MMP‐9 in CCR2−/− mice. At days 14 and 21, lung remodelling and the hydroxyproline content of lung tissues were significantly reduced in CCR2−/− mice. These results suggest that the CCL2/CCR2 functional pathway is involved in the pathogenesis of bleomycin‐induced pulmonary fibrosis and that CCR2 deficiency may improve the outcome of this disease by regulating macrophage infiltration and macrophage‐derived MMP‐2 and MMP‐9 production. Copyright

Targeted Deletion of CC Chemokine Receptor 2 Attenuates Left Ventricular Remodeling after Experimental Myocardial Infarction

A key component of cardiac remodeling after acute myocardial infarction (MI) is the inflammatory response, which modulates cardiac tissue repair. The purpose of this study was to investigate the relationship between the monocytic inflammatory response and left ventricular remodeling after MI using mice deficient in CC chemokine receptor 2 (CCR2), the primary receptor for the critical regulator of CC chemokine ligand 2. Immunohistochemical analysis revealed rapid infiltration of macrophages into infarcted tissue within 7 days in wild-type (WT) mice. However, this process was greatly impaired in CCR2-deficient (CCR2(-/-)) mice. Echocardiography demonstrated beneficial effects of CCR2 deficiency on left ventricular remodeling at 7 and 28 days after MI. In situ zymography showed augmented gelatinolytic activity in WT mice within 7 days after MI, whereas gelatinolytic activity was barely detectable in CCR2(-/-) mice. Moreover, the distribution of gelatinolytic activity in serial sections was very similar to the distribution of macrophages rather than neutrophils. Expression of matrix metalloproteinases and tumor necrosis factor-alpha mRNAs was up-regulated in infarcted regions from WT mice compared to CCR2(-/-) mice at 3 days after MI. Direct inhibition of CCR2 functional pathway might contribute to the attenuation of left ventricular remodeling after MI.

Class A scavenger receptor (CD204) attenuates hyperoxia-induced lung injury by reducing oxidative stress.

To clarify the role of macrophage class A scavenger receptors (SR‐A, CD204) in oxidative lung injury, we examined lung tissue of SR‐A deficient (SR‐A−/−) and wild‐type (SR‐A+/+) mice in response to hyperoxic treatment. Protein levels of bronchoalveolar lavage fluid (BALF) and pulmonary oedema (wet : dry weight ratios) were higher in SR‐A−/− mice than those in SR‐A+/+ mice. Cumulative survival was significantly decreased in SR‐A−/− mice. However, there were no differences in BALF macrophage and neutrophil count between the two groups. Real‐time reverse transcriptase‐polymerase chain reaction (RT‐PCR) revealed that messenger RNA (mRNA) levels of the inducible nitric oxide synthase (iNOS) were increased during hyperoxic injury, and this increase was more prominent in SR‐A−/− mice. Expression levels of iNOS in alveolar macrophages after hyperoxia in vivo and in vitro were higher in SR‐A−/− macrophages compared with SR‐A+/+ macrophages. Immunohistochemistry using anti‐nitrotyrosine antibodies revealed distinctive oxidative stress in the injured lung in both groups, but it was more remarkable in the SR‐A−/− mice. After hyperoxic treatment, pulmonary mRNA levels of tumour necrosis factor‐α(TNF‐α) were elevated more rapidly in SR‐A−/− mice than in SR‐A+/+ mice. Together these results suggest that SR‐A expression attenuates hyperoxia‐induced lung injury by reducing macrophage activation. Copyright

MCP-1/CCR2 signalling pathway regulates hyperoxia-induced acute lung injury via nitric oxide production

To clarify the role of the monocyte chemoattractant protein‐1 (MCP‐1)/C–C chemokine receptor 2 (CCR2) signalling pathway in hyperoxia‐induced acute lung injury, CCR2‐deficient (CCR2−/−) and wild‐type (CCR2+/+) mice were exposed to 85% O2 for up to 6 days. At day 3, body weight significantly decreased and total protein concentration in bronchoalveolar lavage fluid (BALF) was higher in CCR2−/− mice compared with CCR2+/+ mice. Cumulative survivals were significantly lower in CCR2−/− mice than in CCR2+/+ mice. However, the two groups showed no significant differences in both histological changes and number of macrophages in BALF. Real‐time reverse transcriptase‐polymerase chain reaction revealed increased mRNA levels of MCP‐1, interleukin‐1β thioredoxin‐1, and inducible nitric oxide synthase (iNOS) in lung tissues in CCR2−/− mice compared with CCR2+/+ mice. Increased iNOS mRNA levels in alveolar macrophages exposed to 85% O2 for 48 h in vivo or in vitro were significantly higher in CCR2−/− mice than in CCR2+/+ mice. These results suggest that the MCP‐1/CCR2 signalling pathway is protective against hyperoxia‐induced tissue injury by suppressing induction of iNOS and consequent production of reactive oxygen species by activated alveolar macrophages.

Metastatic gastric tumor secondary to pancreatic adenocarcinoma

Metastatic disease, from the pancreas, involving the stomach is an unusual clinical event. Local recurrence, liver metastases, and peritoneal spread are the most common recurrent patterns after curative resection of pancreatic cancer. We report a patient who suffered from gastric metastasis secondary to pancreatic adenocarcinoma 1 year after pancreatectomy. A 49-year-old woman underwent distal pancreatectomy with intraoperative radiation therapy for cancer of the body of the pancreas in October 2002. The histological diagnosis was well-differentiated adenocarcinoma of the pancreas, stage IIB; T1N1M0. Multiple liver metastases were detected on computed tomography (CT) in March 2003. Combination chemotherapy of 5-fluorouracil hepatic arterial continuous infusion and systemic gemcitabine administration led to the disappearance of the liver metastases on CT in September 2003. One month later, she complained of epigastric pain and underwent gastric endoscopy, which revealed a submucosal tumor in the fornix posterior wall. Histological diagnosis of the biopsy specimen was well-differentiated adenocarcinoma, and immunohistochemical studies, using anti-cytokeratin 7 and -20 monoclonal antibodies, were compatible with gastric metastasis from pancreatic carcinoma. A F-18-fluorodeoxyglucose positron emission tomography (FDG-PET) scan revealed a high-uptake lesion, which coincided with the gastric tumor. No other abnormal uptake could be found. Histopatholoical examination of the resected specimen revealed submucosal growth of the metastatic cancer (well-differentiated adenocarcinoma).

Outcome of histologically node-negative esophageal squamous cell carcinoma

The outcome of node-negative esophageal carcinoma and the prognostic significance of lymph node micrometastasis remain unknown. The aim of this retrospective study was to clarify these two points. A series of 98 patients who underwent curative operation for histologically node-negative (pNO in TNM classification) esophageal carcinoma were enrolled in the study. We reviewed the cause of death of these patients. The survival curves were calculated and compared after stratifications according to clinicopathologic parameters. Lymph node micrometastasis in the patients with recurrences was examined using immunohistochemical staining of cytokeratin. Their ages ranged from 45 to 83 years (mean 64.3 years). There were 83 men and 15 women. Altogether, 54 patients were still alive, and 44 had died. A total of 9 patients died from recurrence of their esophageal carcinoma, 33 died from other causes (pneumonia 11, extraesophageal carcinoma 7, and so on), and 2 died from unknown causes. Eight patients had locoregionai recurrences, and two patients had distant recurrences. The overall survival rate for the 98 patients was 58.2%. The survival for patients with pT2 or pT3 tumors was significantly worse than for those with pTis or pTl tumors (p=0.02, log-rank test). Other clinicopathologic factors did not affect the prognosis. Immunohistochemical study found no lymph node micrometastasis in 365 lymph nodes resected from the patients with recurrences. Only the depth of tumor invasion affected the outcome of patients with node-negative esophageal carcinoma. Altogether, 75% of patients died of other causes without recurrence, with the two main causes of death being pulmonary complications and extraesophageal carcinoma in these patients. Lymph node micrometastasis was not associated with recurrence in this series.RésuméL’évolution des cancers de lœsophage NO et la signification des micrométastases ganglionnaires resent inconnues. Le but de cette étude rétrospective a été de clarifier ces deux problèmes. Nous avons inclus dans cette étude, 98 patients qui ont eu une résection à visée curative pour un cncer de l’œsophage (pNO selon la classificaton TNM). Nous avons revu les causes de mortalité chez ces patients. Les courbes de survie ont été calculées et comparées après stratification selon les données clinicopathologiques. Les micrométastases ganglionnaires chez les patients récidives ont été déterminées par une coloration immunohistochimique de la cytokératine. L’àge des patients allait de 45 à 83 ans (moyenne: 65.3 ans). Il y avait 83 hommes et 15 femmes. Cinquante-quatre patients étaient en vie et 44 patients étaient décédés. Neuf patients sont décédés d’une récidive de leur cancer le l’œsophage, 33 sont décédés d’autres causes (principalement une infection pulmonaire:n=11, ou un cancer extra-esophagien: n=7) alors que deux patients sont décédés de cause inconnue. Huit patients ont eu une récidive locorégionale et deux, une récidive à distance. La survie globale pour les 98 patients a été de 58.2%. La survie des patients ayant des tumeurs pT2 ou pT3 a été significativement moins bonne que pour les tumeurs pTis ou pT1 (p=0.02, test du log-rank). Les autres facteurs clinicopathologiques n’ont pas affecté le pronostic. Par l’étude immunohistochimique aucune micrométastase n’a été retrouvée parmi 365 ganglions réséqués chez des patients ayant eu une récidive. Seule la profondeur d’invasion tumorale a influené l’évolution de la maladie chez les patients NO. Parmi les patients décédés, 75% étaient sans récidive; les deux causes principales étant des complications pulmonaires et un cancer extra-esophagien. Dans cette série, les micrométastases n’ont jamais été la cause de récidive.ResumenNo están bien establecidos ni la evolución ni el resultado final del carcinoma escamocelular del esófago con ganglios negativos, tampoco el significado pronóstico de las micrometástasis ganglionares. El propósito de este estudio retrospectivo fue aclarar estos interrogantes. Noventa y ocho pacientes sometidos a operación curativa por carcinoma esofágico con ganglios histológicmente negativos (pNO en la clasificación TNM) fueron incorporados en el estudio. Se revisaron las causas de muerte y se calcularon las curvas de supervivencia para compararlas luego de la estratificación según parámetros clínico patológicos. El estudio de los ganglios para determinar micrometástasis fue hecho en los pacientes que desarrollaron recurrencia mediante coloración immunohistológica de queratina. Las edades oscilaron entre 45 y 83 años (promedio: 65.3); hubo 83 hombres y 15 mujeres. Cincuenta y dos pacientes están vivos, 44 murieron. Nueve murieron por carcinoma recurrente, 33 por otras causas (neumonía 11, carcinoma extraesofágico 7, etc.) y dos por causa desconocida. Ocho presentaron recurrencia local-regional y dos metástasis distantes. La tasa global de supervivencia para los 98 pacientes fue 58.2%. La supervivencia en los pacientes con neoplasmas pT2 o pT3 fue significativamente peor que en los pTis o pT1 (p=0.02). Otros factores clínicos y patológicos no demostraron efecto sobre el pronóstico. El estudio immunohistoquímico no reveló micrometástasis ganglionares en 365 ganglios resecados de pacientes con recurrencias. Sólo la profundidad de la invasión tumoral afectó la evolución final en estos carcinomas esofágicos con ganglios negativos. Setenta y cinco por ciento de los pacientes murieron por causas diferentes de la recurrencia tumoral, y las dos causas principales de muerte fueron la complicación pulmonar y el carcinoma extraesofágico en los pacientes libres de recurrencia. La presencia de micrometástasis ganglionares no apareció asociada con recurrencia en esta serie.

Repeated colon penetration by an ingested fish bone: Report of a case

A 78-year-old man was admitted to Kumamoto Rosai Hospital with right lower abdominal pain. Abdominal computed tomography (CT) showed penetration of the cecum by a foreign body, which looked like a fish bone, as well as thickening of the right lower abdominal wall. We made an initial diagnosis of penetration of the colon by an ingested fish bone and the patient was managed conservatively with fasting, peripheral parental nutrition, and intravenous antibiotics. By the next day, the right lower abdominal pain had diminished and a repeat CT scan showed that the fish bone had moved to the splenic flexure. However, 2 days later, the patient complained of pain in the left upper abdomen and another CT scan showed repeated penetration of the descending colon by the same fish bone. Thus, we removed the fish bone via endoscopic extirpation. The patient had an uneventful postoperative course and was discharged home 6 days later.

Adenocarcinoma of the minor duodenal papilla: report of a case.

We report a case of adenocarcinoma of the minor duodenal papilla, a rare type of duodenal neoplasm. A 76-year-old man with a history of surgery for rectal cancer and gastric cancer was referred to us after a follow-up upper gastrointestinal endoscopy revealed an abnormal elevation in the minor duodenal papilla. The pathological diagnosis of a biopsy specimen was adenocarcinoma. Preoperative examination of other organs revealed a tumor in the ascending colon, which was also identified as adenocarcinoma. We performed synchronous pancreatoduodenectomy and ileocecal resection with lymph node dissection. Histopathological examination of the resected specimen revealed that the papilla tumor arose from the duodenal mucosa and infiltrated the submucosa of the duodenal wall, but not the pancreatic parenchyma. Based on these findings, we diagnosed primary adenocarcinoma of the minor duodenal papilla. To our knowledge, this is only the sixth such case reported in the English-language literature, and we review all six cases after this case report.

Mediastinal growing teratoma syndrome

A 27-year-old man had undergone orchiectomy and chemotherapy for testicular cancer. Despite normalization of raised tumor marker levels after postoperative chemotherapy, computed tomographic scanning demonstrated multiple swellings of the para-aortic lymph nodes with extension from beneath the aortic arch to the bifurcation of the descending aorta. Open biopsies of the para-aortic lymph nodes disclosed mature teraroma without malignant cells. The patient presented the typical features of mediastinal and retroperitoneal growing teratoma syndrome. A two stage resection of the tumors was performed via laparotomy and left thoracotomy. Histological examination of the resected specimens revealed a mature teratoma component without malignant cells. Upon follow-up sixteen months later, the patient was well and without recurrence.