Anterior versus posterior mediastinal reconstruction after esophagectomy in esophageal cancer patients: a systematic review and meta-analysis

PURPOSE

Esophagectomy is the primary surgical treatment for esophageal cancer, although other treatment approaches are often incorporated, including preoperative chemotherapy and chemoradiotherapy. The two major routes of esophageal reconstruction after esophagectomy are the anterior mediastinal (retrosternal, heterotopic) and posterior mediastinal (prevertebral, orthotopic) routes. However, which of these two routes of reconstruction is the most appropriate remains controversial. This systematic review aimed to compare the efficacy and safety of anterior mediastinal reconstruction with those of posterior mediastinal reconstruction after esophagectomy in esophageal cancer.

METHODS

In January 2022, a literature search of the CENTRAL, MEDLINE, and EMBASE databases was conducted to identify all published and unpublished randomized controlled trials, regardless of language. Eight studies were included for quantitative synthesis.

RESULTS

Postoperative death (9/129 and 4/125, risk ratio [RR]: 2.07, 95% confidence interval [CI]: 0.65-6.64) and incidence of anastomotic leak (24/208 and 26/208, RR: 0.95, 95% CI: 0.56-1.62) were not significantly different between the two mediastinal reconstructions. We could not perform a meta-analysis for quality of life, loss of body weight, or postoperative hospital stay due to data limitations.

CONCLUSION

Overall, there was low-quality evidence to suggest that the outcomes of the anterior and posterior mediastinal routes of reconstruction are not significantly different in patients with esophageal cancer.

Analysis of the characteristics and outcomes of patients with pseudomyxoma peritonei of appendiceal origin treated with curative-intent surgery

BACKGROUND

There are no previous studies on pseudomyxoma peritonei regarding the details of surgical procedures included in cytoreductive surgery and quantitative evaluation for peritoneal metastases by region in the abdominal cavity. This study aimed to describe the characteristics and procedural details involved in cytoreductive surgery, and survival outcomes of patients with pseudomyxoma peritonei originating from appendiceal mucinous neoplasm, and identify differences in the difficulty of cytoreductive surgery based on tumor location.

METHODS

Patient characteristics and survival outcomes were studied through a retrospective review. The complete cytoreduction rate (i), the 5-year survival rate for patients with complete cytoreduction (ii), and an index as a complement (i × ii × 100) were described for patients who had tumors larger than 50 mm in one of the 13 regions of the abdominal cavity.

RESULTS

A total of 989 patients were treated with curative-intent cytoreductive surgery. The median peritoneal cancer index was 18 (interquartile range, 6-29), with complete cytoreduction achieved in 702 patients (71%); the major complication rate was 17%. The median overall survival was 92.9 months, compared to 53.8 months for patients who underwent total gastrectomy and 30.4 months for those who underwent total colectomy. In the 13 abdominal regions, the index scores indicating cytoreduction difficulty were categorized into three risk groups: upper and mid-abdominal (>20), lateral abdominal (10-20), and small bowel (<10).

CONCLUSIONS

Cytoreductive surgery offered favorable survival outcomes, even in cases involving total gastrectomy. The difficulty of achieving complete cytoreduction varied across abdominal regions and was classified into three levels.

Upper mediastinal lymph node dissection based on mesenteric excision in esophageal cancer surgery: confirmation by near-infrared image-guided lymphatic mapping and the impact on locoregional control

BACKGROUND

We previously reported a novel method of mesenteric excision for esophageal cancer surgery. The esophagus, trachea, recurrent laryngeal nerves (RLNs), and surrounding lymph nodes (LNs) are contained in a common mesenterium, which we termed the "mesotracheoesophagus". In addition, near-infrared (NIR) image-guided lymphatic mapping has recently been used. The purpose of this study was to confirm the feasibility of NIR image-guided lymphatic mapping for upper mediastinal LN dissection, and to confirm the oncological feasibility of our surgical approach.

METHODS

Fifteen patients with resectable esophageal cancer underwent submucosal injection of indocyanine green (ICG), and underwent robot-assisted esophagectomy. The frequency of ICG positivity in the LN basins along the RLNs, and metastatic frequency were assessed. Regarding the oncological feasibility of our thoracoscopic esophagectomy, the recurrence patterns and survival of 72 consecutive patients who underwent curative resection from 2011 to 2016 were analyzed.

RESULTS

ICG-positive LN basins along the right and left RLNs were found in 12 (80% of 15) patients (3 patients positive for metastatic LNs) and 11 (73% of 15) patients (2 positive for metastatic LNs and 1 false-negative), respectively. All ICG-positive LN basins were found within the mesotracheoesophagus. The sensitivity was 5/6 (83%), and the negative predictive value was 6/7 (86%). Among the 72 patients, with a median follow-up period of 1644 days, only 3 (4.2%) patients developed locoregional recurrence.

CONCLUSIONS

The NIR image-guided lymphatic mapping was feasible. Our results with no ICG-positive basins outside of the '"mesotracheoesophagus", supported our surgical approach. It might become standard, with acceptable locoregional control.

Functional Outcomes of Delta-Shaped Anastomosis After Laparoscopic Distal Gastrectomy

BACKGROUND

We invented a simple and secure method of intracorporeal gastroduodenostomy, the delta-shaped anastomosis (DA), using endoscopic linear stapler only and standardized the DA procedure by resecting two-thirds of the stomach based on the anatomical landmarks. This study aimed to evaluate the feasibility of the standardized DA as the standard reconstruction procedure after a laparoscopic distal gastrectomy assessing functional outcomes including postoperative complications, body weight loss, nutritional status, and endoscopic findings.

METHODS

The medical records of 349 patients with gastric cancer who underwent laparoscopic distal gastrectomy from April 2011 to December 2017 at our hospital were retrospectively reviewed. Functional outcomes were assessed according to nutritional status and endoscopic findings.

RESULTS

The operation time was shorter and complication rate was lower in the standardized DA than those in Billroth-II (BII) and Roux-en-Y (RY). The body weight loss in DA was 10% 1 year postoperatively and remained stable during the follow-up period, which showed no significant difference. The endoscopic findings showed the ratio of residual food in DA was lower than that in RY (DA:RY = 13.3%:13.6% and 8.4%:33.3% at 1 and 3 years postoperatively, respectively). Severe gastritis was extremely rare in DA (6.7% at 1 year and 15.6% at 3 years postoperatively). Bile reflux was more often found in DA than RY (DA:RY = 19.9%:4.8% and 26.6%:0% at 1 and 3 years postoperatively, respectively). Reflux esophagitis was found 10% of DA only.

CONCLUSIONS

Functional outcomes of the standardized DA were satisfactory and feasible. Our intracorporeal Billroth-I reconstruction, by resecting two-thirds of the stomach, can be one of the standard reconstruction methods after a laparoscopic distal gastrectomy.

[A Case of Gastric Cancer with Pericardial Effusion as an Immune-Reactive Adverse Events]

A 67-year-old man diagnosed with clinical Stage Ⅳ gastric cancer was administered nivolumab as fourth-line chemotherapy. After 9 courses, he was emergently admitted with complaints of low blood pressure and general malaise. On the fourth hospital day, he had high-grade fever and elevated serum C-reactive protein. Computed tomography showed a moderate amount of pericardial effusion. He was administered 1.7 mg/kg of methylprednisolone and improved rapidly. A hormonal blood examination showed his adrenal gland disorder. This is the first case in our country of pericardial effusion as an immune-reactive adverse event, which is not well known in Japan.

Laparoscopic gastrectomy with and without prophylactic drains in gastric cancer: a propensity score-matched analysis

BACKGROUND

The number of patients who are undergoing laparoscopic gastrectomy for treating gastric cancer is increasing. Although prophylactic drains have been widely employed following the procedure, there are few studies reporting the efficacy of prophylactic drainage. Therefore, this study assessed the efficacy of prophylactic drains following laparoscopic gastrectomy for gastric cancer.

METHODS

Data of patients who received laparoscopic gastrectomy for treating gastric cancer in our institution between April 2011 and March 2017 were reviewed, and the outcomes of patients with and without a prophylactic drainage were compared. Propensity score matching was used to minimize potential selection bias.

RESULTS

A total of 779 patients who underwent surgery for gastric cancer were reviewed; of these, 628 patients who received elective laparoscopic gastrectomy were included in this study. After propensity score matching, data of 145 pairs of patients were extracted. No significant differences were noted in the incidence of postoperative complications between the drain and no-drain groups (19.3% vs 11.0%, P = 0.071). The days after the surgery until the initiation of soft diet (6.3 ± 7.4 vs 4.9 ± 2.9 days, P = 0.036) and the length of postoperative hospital stay (15.7 ± 12.9 vs 13.0 ± 6.3 days, P = 0.023) were greater in the drain group than those in the no-drain group.

CONCLUSIONS

This study suggests that routinely using prophylactic drainage following laparoscopic gastrectomy for treating gastric cancer is not obligatory.

[A Case of Sigmoid Colon Cancer with Metastasis to the Uterus]

A 65-year-old woman complaining of fetor ex vagina was diagnosed with endometrial adenocarcinoma of the uterus based on the pathological findings of an endometrial biopsy. Sigmoid colon cancer was found on a pre-operative CT scan. Diagnosis of double cancer was made and we performed sigmoidectomy and panhysterectomy with associated resection of both adnexa. Histopathological examination found that the tumor accounted for almost all of the uterine mucosa and over half of the muscular layer. Immunostaining showed CK7 (-), CK20 (+), CDX2 (+), ER (-), and PgR (-), and we diagnosed it as a metastasis to the uterus of the sigmoid colon cancer. The pathological diagnosis was a moderately differentiated adenocarcinoma, pT4b (SI: urinary bladder), pN0 (0/12), H0, P1,M1a (uterus), pStage Ⅳ. As adjuvant chemotherapy, she was administered XELOX for 6 months. Although colorectal cancer rarely metastasizes to the uterus, due to the increase in the prevalence of colorectal cancer, it may be also increase. To choose the best treatment course, it is necessary to diagnose whether it is a primary uterine cancer or a metastatic uterine cancer.

[A Case of Anal Canal Carcinoma with Inguinal Lymph Node Metastasis Treated with Laparoscopic Abdominoperineal Resection]

We report a case of anal canal cancer with inguinal lymph node metastasis treated with laparoscopic abdominoperineal resection combined with inguinal lymph node dissection. A 52-year-old woman was diagnosed with anal squamous carcinoma after excision of an anal canal tumor. Further examination revealed right inguinal lymph node metastasis. Chemoradiotherapy was administered but was discontinued because of serious adverse events. We therefore performed laparoscopic abdominoperineal resection combined with inguinal lymph node dissection. The pathological findings revealed residual squamous cell carcinoma at the lymphatic vessels in the rectal wall and lymph nodes, including the right inguinal region. Therapeutic effect of Grade 1a was achieved in spite of interruption of the chemoradiotherapy. She was discharged 17 days after the operation, and no recurrence was observed for 11 months. Radical resection was performed for the anal canal squamous cell carcinoma with the metastasis to the right inguinal lymph node, even after interruption of the chemoradiotherapy.

[A case of locoregional recurrence of gastric carcinoma that was treated using pancreaticoduodenectomy]

A 71-year-old man underwent distal gastrectomy for gastric cancer in November 2011. The corresponding pathological diagnosis was of well differentiated adenocarcinoma, pT4a(SE), N1(2/15), H0, P0,M0, pStage IIIA. TS-1 was administered as an adjuvant therapy for one year from the second month after the operation. During the 16th month after the operation, we found an elevated tumor marker level and locoregional recurrence near the pancreas head and the abdominal wall upon computed tomography. We could not find any other suspected tumor recurrence using positron-emission tomography and computed tomography. We performed a pancreaticoduodenectomy and transverse colon merger resection in June 2013. Although the tumor marker was again found to be elevated during the second month after the metastasectomy, chemotherapy was continued because obstructive jaundice and gastrointestinal obstruction were prevented by the operation.

[Intraperitoneal chemotherapy with CDDP for patients with peritoneal recurrent gastric cancer following surgical intervention]

We evaluated the efficacy of intraperitoneal chemotherapy with cisplatin (CDDP) for peritoneal recurrent gastric cancer following surgical intervention. Twelve patients were enrolled. The combination systemic chemotherapy was S-1 or S-1 plus paclitaxel (S-1+PTX). PTX was administered intravenously at 80 mg/m² on day S-1 and 15. S-1 was administered at 80 mg/ m²/ day for 7 consecutive days, followed by 7 days of rest, and the cycle was repeated. CDDP was administered intraperitoneally at 40 mg/body on day 8. This treatment was repeated every 4 weeks until disease progression was diagnosed. The survival time(ST)and time to treatment failure(TTF)were estimated. The surgical interventions were gastrectomy in 3 patients, colostomy in 8 patients, and enterostomy in 1 patient. Overall, the median TTF and ST were 294 days and 455 days, respectively. When stratified by surgical method and combination chemotherapy, the median TTF and ST were not statistically significant. However, when stratified by performance status (PS), the median TTF was 352 days for patients with PS 0 and 218 days for those with PS 1, 2 (p=0.0029), whereas the median ST was 553 days for patients with PS 0 and 331 days for those with PS 1, 2 (p=0.0198). In conclusion, the data suggest that intraperitoneal CDDP chemotherapy with systemic chemotherapy is effective for the treatment of extensive peritoneal recurrent gastric cancer, especially in patients with good PS.

Molecular cloning and characterization of mouse Tspan-3, a novel member of the tetraspanin superfamily, expressed on resting dendritic cells

Dendritic cells (DCs) are the most potent antigen-presenting cells and play an essential role for triggering T-cell-mediated immune responses. In search for novel cell surface molecules expressed on DCs involved in T cell priming by representational differential analysis, we identified a mouse homologue of Tspan-3 (mTspan-3), a novel member of the tetraspanin superfamily. The mTspan-3 consists of four hydrophobic, putative transmembrane regions, forming a small and a large extracellular loop, with short intracellular amino and carboxil tails. Although the mTspan-3 is expressed on a variety of immune cell types including resting DCs, its expression on DCs is downregulated during activation induced by cross-linking CD40 with anti-CD40 monoclonal antibody. These results suggest that mTspan-3 may be involved in the function of DCs in association with T cell stimulation.

Virtual pancreatoscopy of mucin-producing pancreatic tumors

We used computer-based virtual endoscopy techniques as a novel approach to clarify the three-dimensional (3D) surgical anatomy of the pancreas and of mucin-producing pancreatic tumors. Thirteen cases (18 lesions) of mucin-producing pancreatic tumors were investigated by virtual pancreatoscopy. Virtual endoscopic images were generated with virtual endoscopy software application on UNIX workstations. We created surface-rendered virtual endoscopic images derived from a computer reconstruction of the cross-sectional magnetic resonance imaging data. Virtual endoscopy could visualize the surfaces of the pancreatic duct and the bile duct, and also demonstrated all cystic tumors. The surfaces of malignant mucin-producing pancreatic tumors were illustrated as being more irregular than those of benign lesions. The virtual endoscopic technique could demonstrate not only a surface-rendered endoscopic image of the tumors but also a 3D reconstructed image of the pancreas. The relationship to anatomic structures located outside the surfaces is continuously maintained and displayed at the same time. Virtual pancreatoscopy was useful for surgical planning of minimally invasive resection of the pancreas.

Inferior head resection of the pancreas for intraductal papillary mucinous tumors

BACKGROUND

Patients with intraductal papillary mucinous tumor have a favorable prognosis after surgical treatment. When this neoplasm is located in the head of the pancreas, resection has conventionally required pancreatoduodenectomy. Although pancreatoduodenectomy can now be performed with a low mortality rate, morbidity still occurs frequently.

METHODS

Between November 1982 and January 1999, 38 intraductal papillary mucinous tumors of the pancreas were resected at the Chiba University Hospital. Seven patients (18%) underwent inferior head resection of the pancreas. In this preliminary study, the operative technique is presented, and its efficacy in improvement of quality of life is evaluated.

RESULTS

Patients with intraductal papillary mucinous tumor underwent resection with no perioperative mortality. After discharge from hospital, 6 patients who underwent inferior head resection were still alive without recurrent disease after a median follow-up of 3 years. However, 1 patient developed peritoneal dissemination and died 18 months after inferior head resection. Patients had regained 98% of preoperative weight 1 year after inferior head resection. N-benzoyl-L-tyrosyl-p-amino-benzoic acid (BT-PABA) excretion test showed the same value before (73%) and after (73%) inferior head resection (n = 7). Pancreatic fistulas occurred more frequently after inferior head resection (38%), but the incidence of major complications was similar between inferior head resection and other types of pancreatic head resection.

CONCLUSIONS

Pancreatic function was well preserved, and patients regained 98% of preoperative weight after inferior head resection of the pancreas. The authors concluded that the limited involvement of intraductal papillary mucinous tumors enables the surgeons to perform inferior head resection of the pancreas.

Intraductal papillary mucinous tumors of the pancreas

BACKGROUND

An increasing number of intraductal papillary mucinous tumors of the pancreas have been reported in recent years. The indolent character and favorable prognosis of this neoplasm have been described.

METHODS

Intraductal papillary mucinous tumors were classified into main duct type (n = 8) and branch type (n = 28) according to the dominant location of the tumor. This single-institute study examined the clinicopathological features and outcome after surgical resection in patients with intraductal papillary mucinous tumors.

RESULTS

The gender, age, tumor size, and prognosis were quite similar for the main duct type and branch type groups. Branch type tumors were more frequently located in the head of the pancreas than were main duct type tumors. Histological examination revealed that 88% of main duct type tumors were adenocarcinomas; however, only 46% of branch type tumors were adenocarcinomas. Five-year survival rates for the patients with all main duct type tumors (n = 8), main duct type adenocarcinoma (n = 7), all branch type tumors (n = 28), and branch duct adenocarcinoma (n = 13) were 100%, 100%, 90.6%, and 90.9%, respectively.

CONCLUSIONS

Intraductal papillary mucinous tumors had a favorable prognosis after surgical treatment. A curative pancreatectomy should be indicated for this localized malignant tumor.

Gilvusmycin, a new antitumor antibiotic related to CC-1065

A new antitumor antibiotic gilvusmycin was isolated from the culture broth of Streptomyces sp. QM16. The structure of gilvusmycin was related to CC-1065 and determined by NMR spectral analysis. Gilvusmycin exhibited antitumor activity against murine leukemia P388 in vivo.

Combined therapy with radiofrequency thermal ablation and intra-arterial infusion chemotherapy for hepatic metastases from colorectal cancer

BACKGROUND/AIMS

In this preliminary study, we investigated the efficacy of combined radiofrequency thermal ablation therapy (RFA) with hepatic arterial infusion chemotherapy (HAI) in the treatment of multiple liver metastases from colorectal cancer.

METHODOLOGY

Nine patients with bilobular multiple metastases was treated. The number of nodules was 6.0 +/- 3.9 (range: 2-13), and the size was 2.1 +/- 1.0 cm (range: 0.5-4.8 cm) in diameter. RFA was performed using a RF generator operating at 460 kHz with a 15-gauge, 4-prong custom RF needle. Treatment temperature was kept at 90-110 degrees C for 5 min. 5-Fluorouracil (5-FU) was administered by weekly 750-1250 mg/body/5 h as the regimen of HAI.

RESULTS

During a 15.2-month follow-up period, 6 of 9 patients survived more than 1 year. Three of the 6 survived more than 2 years. Serum CEA level in 5 patients dropped from 24.5 +/- 9.5 ng/ml to 10.3 +/- 5.5 ng/ml. Local recurrence was observed in 5 patients and new lesions in 4. Extrahepatic recurrence was observed in 5 patients. There were no serious complications but one HAI-related cerebral thrombosis.

CONCLUSIONS

Combined RFA with HAI would be effective and safe. This modality provides a new option for the treatment of multiple liver metastases from colorectal cancer.

A mouse carrying genetic defect in the choice between T and B lymphocytes

Transgenic mice with human CD3epsilon gene have been shown to exhibit early arrest of T cell development in the thymus. The present study shows that, instead of T cells, B cells are generated in the thymus of a line, tg epsilon26, of the human CD3epsilon transgenic mice. The accumulation of mature B cells in the thymus was found only in tg epsilon26 mice, not in other human CD3epsilon transgenic mouse lines or other T cell-deficient mice, including CD3-epsilon knockout mice and TCR-beta/TCR-delta double knockout mice. Hanging drop-mediated transfer into 2-deoxyguanosine-treated thymus lobes showed that lymphoid progenitor cells rather than thymus stromal cells were responsible for abnormal B cell development in tg epsilon26 thymus, and that tg epsilon26 fetal liver cells were destined to become B cells in normal thymus even in the presence of normal progenitor cells undergoing T cell development. These results indicate that lymphoid progenitor cells in tg epsilon26 mice are genetically defective in thymic choice between T cells and B cells, generating B cells even in normal thymus environment. Interestingly, tg epsilon26 thymocytes expressed GATA-3 and TCF-1, but not LEF-1 and PEBP-2alpha, among T cell-specific transcription factors that are involved in early T cell development, indicating that GATA-3 and TCF-1 expressed during thymocyte development do not necessarily determine the cell fate into T cell lineage. Thus, tg epsilon26 mice provide a novel mouse model in that lineage choice between T and B lymphocytes is genetically defective.

Stimulatory effects of lipoprotein(a) and low-density lipoprotein on human umbilical vein endothelial cell migration and proliferation are partially mediated by fibroblast growth factor-2

We previously reported a transient increase in plasma lipoprotein(a) (Lp(a)) concentrations following acute myocardial infarction and surgical operations, and demonstrated Lp(a) accumulation in healing tissues. In the present study, the stimulatory effect of Lp(a) on migration and proliferation of human umbilical vein endothelial cells (HUVEC) was assessed by quantitative assay methods and compared it with that of LDL. Lp(a) stimulated both migration and proliferation of HUVEC in a dose-dependent manner and the stimulatory activities for migration and proliferation were two times higher than those of LDL in terms of moles of apoB. In addition, this stimulatory activity of Lp(a) was not affected by the difference of Lp(a) phenotype. Although each neutralizing antibody to hepatocyte growth factor (HGF), platelet-derived growth factor (PDGF) and interleukin-1beta (IL-1beta) had no further effect on migration and proliferation of HUVEC treated with Lp(a), only antibody to fibroblast growth factor-2 (FGF-2) partially suppressed them. Moreover, pertussis toxin, which inhibits FGF-2-stimulated endothelial cell movement, also partially suppressed Lp(a)-induced HUVEC migration. FGF-2 concentrations in the medium of HUVEC treated with Lp(a) were constant in spite of the increase in FGF-2 mRNA levels in HUVEC. Taken together, it is suggest that Lp(a) stimulates HUVEC migration and proliferation, which is mediated, at least in part, by FGF-2 and may promote the angiogenesis during wound healing.

A case of gallbladder adenomyomatosis with pancreaticobiliary maljunction and an anomaly of the cystic duct joined the common channel

A 46-yr-old woman was admitted to our hospital with mild epigastric pain. Ultrasonography and computed tomography revealed an extremely thickened gallbladder wall. Endoscopic retrograde cholangiopancreatography demonstrated that the main pancreatic duct joined the nondilated common bile duct at the outer point of the duodenal wall (P-C type of pancreaticobiliary maljunction), and the cystic duct joined the common channel directly. The intraoperative amylase levels of the bile juices both in the common bile duct and the cystic duct were high. A cholecystectomy was performed. The wall of the gallbladder was markedly thick, yellowish, elastic, and soft. Histologically, Rokitansky-Aschoff sinus proliferation, hypertrophy of smooth muscles, and fibrosis were seen. The diagnosis was a generalized type of adenomyomatosis. The pathogenesis of the adenomyomatosis was believed to result from chronic stimulation as a result of pancreatic juice reflux. The etiology of this unusual type of junction was considered to be the result of the combination of pancreaticobiliary maljunction and an anomaly of lower junction of the cystic duct.

Functional competence of T cells in the absence of glycosylphosphatidylinositol-anchored proteins caused by T cell-specific disruption of the Pig-a gene

T lymphocytes express various glycosylphosphatidylinositol (GPI)-anchored surface proteins, such as Thy-1 and Ly-6A. However, functional contribution of GPI-anchored proteins in T cell activation is as yet poorly understood. Here we report the generation of mutant mice deficient in the expression of GPI-anchored molecules exclusively in their T cells. We established mice carrying three identically oriented lox-P sites within the Pig-a gene, which encodes a component essential for the initial step of GPI anchor biosynthesis. These mice were crossed with mice carrying the Cre recombinase gene driven by the T cell-specific p56lck proximal promoter. Offspring carrying both the lox-P-containing Pig-a gene and the Cre transgene exhibited almost complete loss of the surface expression of GPI-anchored molecules on peripheral T cells. Interestingly, those T cells deficient in GPI-anchored molecules were capable of responding to T cell receptor stimulation in vitro and in vivo. These results indicate that T cells lacking the expression of GPI-anchored molecules are functionally competent in exerting TCR-mediated immune responses.

Expression and function of c-Met, a receptor for hepatocyte growth factor, during T-cell development

The c-Met oncoprotein is a cell-surface receptor for hepatocyte growth factor (HGF). Signals through HGF and c-Met have been appreciated for their crucial roles in the development of many cell types, including liver cells. The present study examined whether c-Met is expressed in the thymus and whether c-Met/HGF signals can regulate T-cell development in the thymus. We have found that mRNA transcripts encoding c-Met are expressed in mouse thymus. The c-Met transcripts were expressed at higher levels in fetal and neonatal thymus than in adult thymus, and were mostly expressed by lymphoid cells rather than by stromal cells. Interestingly, the addition of HGF to fetal thymus organ cultures increased the generation of mature T cells expressing high levels of T-cell antigen receptors. These results indicate that c-Met is expressed in the thymus during early ontogeny, and that c-Met/HGF signals can promote T-cell development.

Pertussis toxin can replace T cell receptor signals that induce positive selection of CD8 T cells

CD4+ helper T lymphocytes and CD8+ killer T lymphocytes are both generated in the thymus from common precursor cells expressing CD4 and CD8. The development of immature CD4 CD8+ thymocytes into mature 'single-positive' T cells requires T cell antigen-receptor (TCR)-mediated positive selection signals. Although it is known that the recognition specificity of TCR expressed by CD4+ CD8+ thymocytes determines their fate to become either CD4+ or CD8+ T cells, the molecular signals that direct precursor thymocytes to become CD4+ and CD8+ T cells are unclear. By using ZAP-70 mutant thymus organ cultures in which T cell development is arrested at the CD4+ CD8+ thymocyte stage, the present study shows that distinct biochemical treatments can selectively restore the generation of mature CD4+ and CD8+ T cells, bypassing TCR-induced positive selection signals. The combination of phorbol ester and ionomycin selectively restores the generation of CD4+ CD8- TCR(high) cells, consistent with previous results. On the other hand, we find that the generation of CD4- CD8+ TCR(high) cells is selectively induced by pertussis toxin. Interestingly, the signals generated by pertussis toxin, which increase Notch expression, can dominate the signals by phorbol ester and ionomycin, steering thymocyte development to CD8 lineage. These results indicate that distinct biochemical signals replace TCR signals that selectively induce positive selection of CD4+ and CD8+ T cells, and that biochemical treatment can manipulate the development and choice of CD4+ and CD8+ T cells.

Inhibition of growth and invasive activity of human pancreatic cancer cells by a farnesyltransferase inhibitor, manumycin

The effects of manumycin, a competitive farnesyltransferase (FTase) inhibitor, on pancreatic cancer cell lines with or without K-ras mutation were studied. Manumycin inhibited the growth of human pancreatic cancer cells (SUIT-2, MIA PaCa-2, AsPC-1, BxPC-3) in a dose-dependent manner. The 50% inhibitory concentration (IC50) in cell lines with a mutant K-ras gene (SUIT-2, MIA PaCa-2, AsPC-1) was lower than that in BxPC-3 with a wild-type ras. Both mitogen-activated protein kinase activity after growth stimuli and the ability for chemotactic invasion were markedly more inhibited by manumycin in SUIT-2 than in BxPC-3. These results suggest that mutated Ras is more sensitive to manumycin than the wild type. Furthermore, tumor growth and liver metastasis in nude mice inoculated with manumycin-treated SUIT-2 cells were inhibited dose dependently. Inhibition of Ras activity might be a new anticancer strategy in pancreatic cancer in which Ras plays a role.

Hepatic protein synthesis rate of liver specimens as a predictor of viability in rat cold ischemia liver transplantation model

BACKGROUND/AIMS

We have previously reported that the hepatic protein synthesis rate, calculated as the uptake rate of L-[4.5 3H] leucine by the protein fraction during a 10-min incubation of a 16-G needle biopsy specimen of liver tissue, represents a high level of liver function and is therefore useful for evaluating liver function. We investigated the hepatic protein synthesis rate level in a pre-transplant liver to learn if it might predict the outcome in a rat orthotopic liver transplantation model.

METHODS

Grafts were stored, liver specimens were obtained using a 21-G Chiba type II skinny needle, and the hepatic protein synthesis rate was calculated. Subsequently, liver transplantation was performed, and the hepatic protein synthesis rate level of revascularized liver, tissue blood flow rate, serum alanine aminotransferase, lactate dehydrogenase, hyaluronic acid, ketone body rate, and 2-week survival were examined.

RESULTS

The hepatic protein synthesis rate of pretransplant liver was correlated with parameters of post-transplant liver function: hepatic protein synthesis rate of the revascularized liver (r=0.92, p<0.0001), tissue blood flow rate (r=0.77, p<0.004), serum alanine aminotransferase (r=-0.69, p<0.003), lactate dehydrogenase (r=-0.54, p<0.03), hyaluronic acid (r=-0.86, p<0.0002), and ketone body rate (r=0.57, p<0.02). Pretransplant hepatic protein synthesis rate in survivors was 263.6+/-54.2 nmol/mg protein/10 min, while that in nonsurvivors was significantly lower at 162.0+/-39.0 (p<0.0001). When evaluation was made using a logistic regression model, the accuracy predicted using the value of hepatic protein synthesis rate was 95% (19/20).

CONCLUSIONS

These results suggest that measuring the hepatic protein synthesis rate of the grafts with a 21-G Chiba type II skinny needle may be a predictive criterion in the assessment of graft viability.

B220 expression by T lymphoid progenitor cells in mouse fetal liver

The present study has characterized T lymphoid progenitor cells that reside in mouse fetal liver. Day 14 fetal liver contains progenitor cells that can differentiate into mature T cells upon being transferred into the thymus by hanging drop cultures. Fractionation of fetal liver cells indicated that T progenitor cells were confined in TER119- CD45+ FcR(low) cells. To our surprise, B220+ rather than B220- fraction in TER119- CD45+ FcR(low) fetal liver cells exhibited efficient progenitor activity generating T cells. Progenitor activity by the B220+ fetal liver cells was restricted to T cells, B cells, and macrophages at frequency approximately 1/10, approximately 1/10, and approximately 1/20, respectively, of isolated B220+ cells. B220+ fetal liver cells did not contain detectable D-J rearrangement of TCR-beta gene and were c-kit+ IL-7R+ Thy-1- CD3- CD4(low) CD8- CD25- CD44+. B220+ fetal liver cells expressed mRNAs encoding TCR-beta, pT alpha, Ig alpha, and VpreB. Interestingly, TCR beta-chains were expressed by B220+ fetal liver cells in the VDJ-rearranged TCR-beta-transgenic mice, indicating that TCR-beta transcription and B220 expression are activated simultaneously by the transgenic B220+ fetal liver cells. These results indicate that B220 is expressed by fetal liver lymphoid progenitor cells that can become T cells, and suggest that lymphoid progenitor cells in fetal liver concurrently undergo T- and B-specific molecular events within a single cell.

B220 expression by T lymphoid progenitor cells in mouse fetal liver

The present study has characterized T lymphoid progenitor cells that reside in mouse fetal liver. Day 14 fetal liver contains progenitor cells that can differentiate into mature T cells upon being transferred into the thymus by hanging drop cultures. Fractionation of fetal liver cells indicated that T progenitor cells were confined in TER119- CD45+ FcR(low) cells. To our surprise, B220+ rather than B220- fraction in TER119- CD45+ FcR(low) fetal liver cells exhibited efficient progenitor activity generating T cells. Progenitor activity by the B220+ fetal liver cells was restricted to T cells, B cells, and macrophages at frequency approximately 1/10, approximately 1/10, and approximately 1/20, respectively, of isolated B220+ cells. B220+ fetal liver cells did not contain detectable D-J rearrangement of TCR-beta gene and were c-kit+ IL-7R+ Thy-1- CD3- CD4(low) CD8- CD25- CD44+. B220+ fetal liver cells expressed mRNAs encoding TCR-beta, pT alpha, Ig alpha, and VpreB. Interestingly, TCR beta-chains were expressed by B220+ fetal liver cells in the VDJ-rearranged TCR-beta-transgenic mice, indicating that TCR-beta transcription and B220 expression are activated simultaneously by the transgenic B220+ fetal liver cells. These results indicate that B220 is expressed by fetal liver lymphoid progenitor cells that can become T cells, and suggest that lymphoid progenitor cells in fetal liver concurrently undergo T- and B-specific molecular events within a single cell.

Clinicopathologic study of nasal T/NK-cell lymphoma among the Japanese

A high prevalence of nasal lymphoma expressing a T- or natural killer (NK)-cell phenotype (NTCL) with frequent association of Epstein-Barr virus (EBV) has been indicated in Asians. To characterize NTCL among the Japanese, the clinicopathologic features of 32 cases were evaluated and the cases were also analyzed for EBV-RNA using an ISH method. Morphologically, 31 cases were identified by atypical pleomorphic lymphoid infiltrates with polymorphous, angicentric, and necrotic features. Their lymphoma cells ranged in size from small to large and were mixed in varying proportion from case to case. The other one case showed a monomorphic 'blastic' appearance. EBV-encoded small RNA (EBER) was detected in the neoplastic cells of 27 of the 32 cases examined. In the five EBV-negative cases, one was the 'blastic' type. Clonal T-cell receptor gene rearrangement was detected in none of seven cases examined. The patients had a median follow-up of 9 months (range, 1 month to 14 years and 11 months). The Kaplan-Meier estimate of overall survival was 49% at 5 years, correlating with clinical stage. These data support the concept that most cases of NTCL are identified as tumors with T/NK-cell characteristics and EBV association, distinctly different from other peripheral T-cell lymphomas. Furthermore, the one case of an EBV-negative 'blastic' variant appears not to fit well into the pleomorphic category but more closely resembles the pathologic features of extranasal angiocentric lymphoma with lymphoblastoid appearance. This study also showed no clear difference in clinical aspects other than the original site or in prognosis, between NTCL and extranasal angiocentric lymphomas despite the higher incidence of EBV association and the tendency for that peculiar anatomical site to be restricted to the former group.

Relevance of local Th2-type cytokine mRNA expression in immunocompetent infiltrates in inflamed gingival tissue to periodontal diseases

It has been suggested that the types of inflammatory round cell infiltrates and the divergence in the cytokine production profile by macrophages and helper T cells regulate the course of infectious or inflammatory diseases, including periodontitis and gingivitis. We examined the expression of IL-1alpha, IL-1beta, IL-2, IL-4, IL-5, IL-6 and tumour necrosis factor-alpha (TNF-alpha) mRNA in the inflamed gingiva by in situ hybridization. The results of single-cell analysis were used as data sets for statistical analyses. The density of cells expressing IL-1alpha, IL-4 and IL-5 mRNA was higher in periodontitis than in gingivitis. IL-2 mRNA-expressing cells were almost absent in gingivitis specimens. Principal component analysis disclosed three factors explaining 84.8% of the variance: one accounting for 40.5% of the variance and mainly regulated by IL-1alpha, IL-1beta, IL-6 and TNF-alpha, and two others, explaining 29.9% and 14.4% of the variance, describing the relationship between the types of cytokines derived from macrophages or Th2 type. These results suggest that the cytokines produced by inflammatory cells infiltrating in the gingival tissue are influential on the progression of gingivitis, an acute and reversible inflammatory condition, to chronic and destructive periodontitis. Thus, periodontal disease progression may be regulated by the local cytokine network, and the bias in this network towards a Th2-type cytokine dominance could be an exacerbating factor.

IL-1 beta mRNA as the predominant inflammatory cytokine transcript: correlation with inflammatory cell infiltration into human gingiva

Expression of mRNA for IL-1 alpha, IL-1 beta, IL-2, IL-4, IL-5, IL-6 and TNF-alpha in inflamed gingiva was quantitatively examined by ribonuclease protection assay and in situ hybridization. The IL-1 beta mRNA expression level was statistically high (P < 0.05) in periodontitis-affected tissues compared with that in gingivitis-affected tissues. The densities of macrophages (identified as CD68-positive cells) and CD45RO-positive cells infiltrating in the inflamed gingiva correlated statistically with IL-1 beta transcript levels (macrophages, P < 0.001; CD45RO-positive cells, P < 0.002). In situ hybridization revealed IL-1 beta mRNA expression in infiltrating cells, presumed to be macrophages. The IL-1 alpha and IL-6 mRNA expression levels were much lower than the IL-1 beta transcript level, and mRNAs for IL-2, IL-4, IL-5 and TNF-alpha were negligible in these gingival tissues. The results indicate that IL-1 beta is a cytokine expressed predominantly in inflamed gingiva and reflects the density of infiltrating macrophages and other leukocytes.

CD3-induced apoptosis of CD4+CD8+ thymocytes in the absence of clonotypic T cell antigen receptor

Clonal selection of T cells mediated through the T cell antigen receptor (TCR) mostly occurs at the CD4+CD8+ double positive thymocyte stage. Immature CD4+CD8+ thymocytes expressing self-reactive TCR are induced to die upon clonotypic engagement of TCR by self antigens. CD3 engagement by antibody of the surface TCR-CD3 complex is known to induce apoptosis of CD4+CD8+ thymocytes, a process that is generally thought to represent antigen-induced negative selection in the thymus. The present study shows that the CD3-induced apoptosis of CD4+CD8+ thymocytes can occur even in TCR alpha- mutant mice which do not express the TCR alpha beta/CD3 antigen receptor. Anti-CD3 antibody induces death of CD4+CD8+ thymocytes in TCR alpha- mice either in cell cultures or upon administration in vivo. Interestingly, most surface CD3 chains expressed on CD4+CD8+ thymocytes from TCR alpha- mice are not associated with clonotypic TCR chains, including TCR beta. Thus, apoptosis of CD4+CD8+ thymocytes appear to be induced through the CD3 complex even in the absence of clonotypic antigen receptor chains. These results shed light on previously unknown functions of the clonotype-independent CD3 complex expressed on CD4+CD8+ thymocytes, and suggest its function as an apoptotic receptor inducing elimination of developing thymocytes.

Cloning of a complementary DNA encoding an 80 kilodalton nuclear cap binding protein

It has been shown that the monomethylated cap structure plays important roles in nuclear events. The cap structure has been implicated in the enhancement of pre-mRNA splicing. More recently, this structure has also been suggested to facilitate RNA transport from the nucleus to the cytoplasm. We have previously identified and purified an 80kD Nuclear Cap Binding Protein (NCBP) from a HeLa cell nuclear extract, which could possibly mediate these nuclear activities. In this report, we describe cloning of complementary DNA (cDNA) encoding NCBP. The partial protein sequences of NCBP were determined, and the full-length cDNA of NCBP was isolated from HeLa cDNA libraries. This cDNA encoded an open reading frame of 790 amino acids with a calculated molecular mass of 91,734 daltons, which contained most of the determined protein sequences. However, the protein sequence had no significant homology to any known proteins. Transfection experiments demonstrated that the epitope-tagged NCBP, transiently expressed in HeLa cells, was localized exclusively in the nucleoplasm. Similar experiments using a truncated NCBP cDNA indicated that this nuclear localization activity is conferred by the N-terminal 70 amino-acid region.

Imprint cytology of low-grade B-cell lymphoma of mucosa-associated lymphoid tissue arising in the thymus: a case report

Low-grade B-cell lymphoma of mucosa-associated lymphoid tissue (MALT) arising in the thymus is a very rare tumor with characteristic morphologic features. We describe a case of thymic low-grade B-cell MALT lymphoma occurring in a 59-yr-old woman with Sjögren's syndrome, in whom the definite diagnosis was difficult at the time of surgery. An immunohistologic and genotypic study, however, was diagnostic of lymphoma. A review of cytologic material was undertaken, and it was felt that the cytologic features in Giemsa-stained preparations in imprint smears were present that initially should have enabled the correct cytodiagnosis and distinction from the other thymic lesions. The findings presented in this study were considered to contribute to the cytodiagnosis of a thymic lesion, which might, in the past, have been erroneously interpreted as another lymphoproliferative disorder.

Morphometrical and biochemical analysis on autofluorescent granules in various tissues and cells of the rats under several nutritional conditions

The effects of age and nutritional conditions on accumulation of autofluorescent granules in various organs and tissues of male Sprague-Dawley rats were compared morphometrically. The relative intensity of the specific fluorescence of these autofluorescent granules was similar in all tissues and cells examined. In almost all cases, there were more autofluorescent granules in the 12-month experiment than in the 4-month one. Multiple necrotic foci of myofibrils with an accumulation of autofluorescent granules were seen in striated muscles in the rats on vitamin E-deficient diets for 12 months. In splenocytes, renal proximal convoluted tubules and hepatic cells, autofluorescent granules quantitatively increased significantly with an increase of the corn oil contents in the diets. The increase was rather marked in the splenocytes and renal epithelia of vitamin E-deficient rats. In the Purkinje cells and bronchial epithelial cells, no significant differences were noted according to the difference in the vitamin E and corn oil contents in diets. The accumulation of autofluorescent granules was not merely considered to be an age-related change, but to be influenced by a relationship to the cell metabolism and functional activity in various organs.

Age changes of myofibrils of human minor pectoral muscle

Micro- and ultramicromeasuring studies have been made on the age changes of surgically resected minor pectoral muscles in 200 Japanese females of various ages (26-80 years). With advancement of age, muscle fibers of type I decreased in number and increased in size, and the age-related increase in size is not considered to be due to an increase in number of myofibrils but seems to be due to an increase in their volume resulting from an increase in the number of myofilaments.

Age changes in size and number of muscle fibers in human minor pectoral muscle

Micromeasuring studies have been made on the senile changes of the surgically resected minor pectoral muscles in 200 Japanese females of various ages (26-80 years). The microscopic differentiation between type I (red) and type II (white) fibers were made by the histochemically demonstrated myosin-ATPase activity with frozen sections and also by the immunohistochemical demonstration of beta-enolase in the paraffin sections with indirect antibody method. The decrease with age in weight of the muscle was not markedly observed. Muscle fibers of type I were significantly decreased in number and increased in size after 60 years of age. However, size of muscle fibers of type II decreased gradually after 40 years of age. However, size of muscle fibers of type II decreased gradually after 40 years of age. Total volume of type I muscle fibers was not changed according to age, on the contrary, that of the type II fibers decreased significantly after 60 years of age.

The progress of adrenoleukodystrophy as revealed by auditory brainstem evoked responses and brainstem histology

Serial studies of auditory brainstem evoked responses (ABR) and slow vertex responses (SVR) were obtained during the progress of adrenoleukodystrophy in a 6-year-old boy. This child was normal until 5 years of age. His illness began with a gait disturbance, dysarthria, and hearing difficulty. Later, spastic paralysis, serious deafness, and blindness appeared. He died of respiratory failure 2 years after the onset. The ABR was normal at onset but changed to an abnormal pattern. Initially, there was lengthening of the wave V-I interpeak interval. This was followed by the disappearance of the later components as his general condition deteriorated. At the terminal stage, only a prolonged wave I was recordable. The postmortem pathology revealed demyelination of auditory nerves and remarkable neuronal loss in the auditory pathways of the brainstem; in addition, there was a variety of extensive degeneration throughout the cerebrum, in particular the complete degeneration of the white matter with secondarily occurring ganglionic cell changes. These date suggest that degeneration of the brainstem from rostral to caudal levels occurred.