Preoperative serum hyaluronic acid level as a prognostic factor in patients undergoing hepatic resection for hepatocellular carcinoma

Background

Hyaluronic acid (HA) probably plays a critical role in tumorigenesis. The clinical significance of serum HA concentration in patients with hepatocellular carcinoma (HCC) remains to be elucidated. This study analysed the relationship between preoperative serum HA levels and prognosis after hepatic resection in patients with HCC.

Methods

Consecutive patients who underwent hepatic resection for HCC between September 1999 and March 2012 were included in this retrospective study. Serum HA levels were measured within 4 weeks before surgery by an immunoturbidimetric automated latex assay. The cut-off level for preoperative serum HA was validated using a time-dependent receiver operating characteristic (ROC) curve analysis. The prognostic impact of preoperative serum HA levels was analysed using Cox proportional hazards models.

Results

A total of 506 patients of median age 66 years (405 men, 80·0 per cent) were analysed. The median length of follow-up was 32 months. High serum HA levels (100 ng/ml or above) were associated with shorter recurrence-free survival (P < 0·001) (hazard ratio (HR) 1·50, 95 per cent confidence interval 1·17 to 1·93; P = 0·002) and overall survival (P = 0·001) (HR 1·46, 1·03 to 2·07; P = 0·033). In patients with HCC without severe liver fibrosis, serum HA level was correlated with multiple tumours (P = 0·039), early recurrence (P = 0·033), and poor recurrence-free (P < 0·001) and overall (P = 0·024) survival.

Conclusion

High preoperative serum HA levels predict poor prognosis in patients with HCC after hepatic resection, and may serve as a future biomarker.

CD44s signals the acquisition of the mesenchymal phenotype required for anchorage-independent cell survival in hepatocellular carcinoma

Background:

Circulating tumour cells (CTCs) have an important role in metastatic processes, but details of their basic characteristics remain elusive. We hypothesised that CD44-expressing CTCs show a mesenchymal phenotype and high potential for survival in hepatocellular carcinoma (HCC).

Methods:

Circulating CD44⁺CD90⁺ cells, previously shown to be tumour-initiating cells, were sorted from human blood and their genetic characteristics were compared with those of tumour cells from primary tissues. The mechanism underlying the high survival potential of CD44-expressing cells in the circulatory system was investigated in vitro.

Results:

CD44⁺CD90⁺ cells in the blood acquired epithelial–mesenchymal transition, and CD44 expression remarkably increased from the tissue to the blood. In Li7 and HLE cells, the CD44^high population showed higher anoikis resistance and sphere-forming ability than did the CD44^low population. This difference was found to be attributed to the upregulation of Twist1 and Akt signal in the CD44^high population. Twist1 knockdown showed remarkable reduction in anoikis resistance, sphere formation, and Akt signal in HLE cells. In addition, mesenchymal markers and CD44s expression were downregulated in the Twist1 knockdown.

Conclusions:

CD44s symbolises the acquisition of a mesenchymal phenotype regulating anchorage-independent capacity. CD44s-expressing tumour cells in peripheral blood are clinically important therapeutic targets in HCC.

Distal pancreatectomy using a no-touch isolation technique

BACKGROUND AND AIMS

Distal pancreatectomy is the only effective treatment for cancers of the pancreatic body and tail. The recurrence rate after DP has remained high. In an effort to over-come this problem, we developed a no-touch surgical technique for DP. This is a pilot study to see if distal pancreatectomy can be technically done using a no-touch surgical technique with-out deteriorating the post-operative prognosis.

PATIENTS AND METHODS

From November 2000 through May 2011, 16 pancreatic ductal adeno-carcinoma patients have been operated on using a no-touch technique by a single operator. We described the surgical technique, and we reported our preliminary experience. During the procedure, the pancreatic body and tail is neither grasped nor squeezed by the surgeon. And all drainage vessels from the pancreatic body and tail are ligated and divided during the early phase of the operation. Furthermore, for improved dissection of the retroperitoneal tissue (rightward and posterior margins), we use a hanging and clamping maneuver and dissection behind Gerota's fascia.

RESULTS

In the current series, the posterior and rightward resection margins were free in all patients, although seven were positive for anterior serosal invasion. The post-operative prognosis was not deteriorated with this technique.

CONCLUSION

No-touch distal pancreatectomy technique may have some theoretical advantages, which merit future investigation in randomized controlled trials.

Clinical benefit of liver hanging maneuver for right-side major hepatectomy

15171

Background: Liver hanging maneuver is a new technique in anterior approach of major hepatectomy. However, the impact of the maneuver has never been fully investigated in patients with liver tumors. To evaluate the surgical benefits of liver hanging maneuver, we set up a comparative study in right-side major hepatectomy. Methods: From 2000 to 2006, 326 hepatectomy were performed in our institution. Fifty-eight patients with liver tumor (hepatocellularcarcinoma in 36, metastatic liver tumor in 13, and the others in 9) considered for right-side major hepatectomy were prospectively analyzed. Right-side hepatectomy included 26 right hepatectomy, 24 extended right hepatectomy, and 8 tri-segmentectomy. The patients were devided into a group with conventional approach (n = 21), a group with anterior approach without hanging maneuver (n = 19), and a group with approach with liver hanging maneuver (n = 18). In the three groups, age, body mass index, child-pugh classification, type of liver tumor, staging in hepatocellularcarcinoma, tumor size, resected liver weights, intraoperative blood loss, frequency of transfusion and surgical time were analyzed. Results: In conventional approach, anterior approach without hanging maneuver, and approach with liver hanging maneuver, mean age was 55, 59, and 65 years, and mean tumor size was 65, 75, and 108mm, respectively. Patients with liver hanging maneuver were significantly elder (p<0.05) and have larger tumor size (p<0.01). There were no significant differences in body mass index, child-pugh classification, type of liver tumor, staging in hepatocellularcarcinoma, and resected liver weights. Mean intraoperative blood loss was 1771, 805, and 704g, and mean surgical time was 562, 483, and 435minutes, and the frequency of red blood cell transfusion was 33, 21, and 17%, respectively. Patients with liver hanging maneuver had significantly less intraoperative blood loss (P=0.0001) and surgical time (P=0.002). The frequency of red blood cell transfusion in the liver hanging maneuver group was significantly lower than that of the conventional group (p<0.05). Postoperative morbidity rate were 33.3, 15.8, and 16.7%, respectively. Conclusions: Liver hanging maneuver is less invasive and a quite useful method for right-side major hepatectomy.

No significant financial relationships to disclose.

Doubling time of preoperative serum alpha-fetoprotein level can predict recurrence and prognosis after hepatic resection of hepatocellular carcinoma

15118

Background: It is quite important to predict postoperative recurrence or prognosis in the patients with hepatocellular carcinoma (HCC) before surgery. There have been few reports about the value of doubling time of preoperative serum a-fetoprotein (AFP) or protein induced by vitamin K absence (PIVKA-II) levels. Methods: Between January 2000 to December 2005, 160 consecutive HCC patients underwent hepatic resections in our institution. Serum AFP and PIVKA-II level was prospectively measured at least two points before surgery to calculate a doubling time. Clinical factors such as age, gender, BMI, etiology of hepatitis, degree of liver damage, gross tumor type, tumor size, tumor numbers, portal vein tumor thrombosis (PVTT), and AFP-L3 were concurrently investigated. Univariate and multivariate analyses were done to clarify predictive factors of postoperative recurrence and survival. Results: There were no relationship between preoperative levels and doubling time of both tumor markers. In univariate analysis, significant predictors of postoperative recurrence were AFP > 200 ng / ml, PIVKA-II > 200 mAU / ml, AFP-L3 > 10%, non-simple nodular type tumor, tumor size > 3 cm, multiple tumors, PVTT positive, and doubling time of AFP < 40 days. The significant prognostic factors were AFP > 200 ng / ml, HBs antigen positive, non-simple nodular type tumor, multiple tumors, PVTT positive, and doubling time of AFP < 40 days. In multivariate analysis, multiple tumors (odds ratio: 1.48), and doubling time of AFP < 40 days (odds ratio: 2.17) were significant predictors of recurrence. The significant prognostic factors were non-simple nodular type tumor (odds ratio: 6.41), multiple tumors (odds ratio: 7.62), and doubling time of AFP < 40 days (odds ratio: 6.49). Postoperative mean recurrence free survival time of HCC patients with doubling time of AFP < 40 days was only 2.8 months and mean survival time was 34 months. Conclusions: In HCC patients, doubling time of preoperative serum AFP level is useful to predict early recurrence and poor prognosis. Perioperative adjuvant therapy should be considered for such high risk patients.

No significant financial relationships to disclose.

Radio-frequency ablation (RFA) is equivalent in therapeutic effect but safer compared to microwave coagulation therapy (MCT) for hepatocellular carcinoma

15064

Background: Radio-frequency ablation (RFA) and microwave coagulation therapy (MCT) have been developed as a useful locoregional treatment for hepatocellular carcinoma (HCC). It is still unclear which ablation therapy is superior for the patients with HCC, from the viewpoint of not only short term but also long term outcome. Methods: Between January 1991 and December 2005, 430 patients with HCC were treated with ablation therapy (230 RFA and 200 MCT) in our institution. Enroll criteria of this therapy were as follows; 1) unresectable HCCs, 2) each smaller than 3 cm, 3) up to three nodules, 4) without vascular invasion. Either percutaneous (P), endoscopic (E) or open (O) approach was selected individually based on location, size, number, or other factors. Treatment was repeated until complete ablation of HCC. Results: 1. Proportion of Child B or C was 62% and 60%; Stage III or IV was 56% and 58% in the patients with RFA and MCT, respectively. 2. Average tumor size and tumor number was 27mm/2.5 and 26mm/1.9 in the two groups. 3. Approaches were P: 55%, E: 33%, O: 12% in RFA and P: 48%, E: 30%, O: 22% in MCT. 4. Number of treatment was 1.1 in RFA and 1.2 in MCT. 5. Recurrence rate at the therapeutic site was 8% in RFA and 12% in MCT. Especially, endoscopic RFA provided a quite low recurrence rate (3%). 6. Cumulative 5-year survival was 52% versus 45% in the two groups. 7. Complication rate was significantly lower in RFA (5%) compared to MCT (11%). Intraabdominal tumor seeding (1% in MCT) and liver abscess formation (4% in MCT) was never encountered in RFA. Conclusions: Radio-frequency ablation for hepatocellular carcinoma is a safer procedure and can provide a similar favorable long- term prognosis compared to microwave coagulation therapy.

No significant financial relationships to disclose.

A novel multimodality treatment for resectable pancreatic cancer (PC)

4630

Background: Patients with PC often suffer from tumor recurrence despite curative resection, thus indicating that systemic therapy added to local control might be required to further improve the survival. The aim of this phase II trial was to assess the feasibility and tolerance as well as overall survival of a novel multimodality therapy composed of pancreatic resection and intraoperative radiation therapy (IORT) combined with neoadjuvant (NAC) and adjuvant (AC) combination chemotherapy for patients with PC. Methods: Eligibility criteria included: no distant metastases / no tumor extension to the CA or the SMA by imaging, tumor size ≥ 1 cm, ECOG PS ≤ 2, age < 80, and normal organ function. For NAC, 5-FU was administered at a dose of 125 mg/m2 on days 1–5 every week as a continuous pancreatic and hepatic arterial infusion, and gemcitabine was infused intravenously at a dose of 800 mg/m2 for 30 min once weekly for 2 weeks. Pancreatic resection combined with IORT (30 Gy, 12 Mev of electron beam) was performed after a one-week rest following the completion of NAC. AC was performed in the same regimen as NAC after the recovery from surgery. We performed intension to treat analyses. Results: Between 2001 and 2006, 32 pts were enrolled: 32 received NAC, 28 received AC, and 28 received IORT. Of 32 pts given NAC, 13 had grade 3–4 hematological toxicity. All pts underwent surgery, including R0 resection in 26 pts, without delay by NAC- related toxicity. Of 28 pts given AC, 18 had grade 3–4 hematological, and 6 had non-hematological toxicity, although no chemotherapy-related death was observed. The median follow-up period was 20 months (rang 3.9 to 67.4). Overall survivals at 1, 3, and 5 years were 77.0 %, 60.2 %, and 48.1 %, respectively. Median survival was 38.5 months. Conclusions: This new multimodality treatment is feasible and tolerable, and may contribute to the survival benefit of patients with PC.

No significant financial relationships to disclose.

Whole-liver graft without the retrohepatic inferior vena cava for sequential (domino) living donor liver transplantation

Grafts used in Domino liver transplantation (LT) obtained from living donor liver transplantation (LDLT) for familial amyloid polyneuropathy (FAP) patients have been mainly used as reduced grafts. Because of small-for-size problems seen in LDLT, using whole liver grafts could improve post-LT outcome. Eight consecutive Domino LDLT using whole livers without retrohepatic inferior vena cava (IVC) from FAP patients were retrospectively analyzed. The graft weight/recipient's body weight ratio (GWRW) in the domino recipients ranged from 1.28% to 2.4% (mean: 1.52). Multiple vascular reconstructions in the whole-liver domino LT resulted in longer than usual warm ischemia time (mean: 64 min); however immediate post-operative recovery of hepatic function was uneventful. At 8-40 months after the transplant, all the FAP patients are well and all of the domino recipients are alive. Domino LT using a whole FAP liver from a LDLT for a FAP patient presents satisfactory results, even though the transplant procedure is technically complicated.

Constitutive IL-8 expression in cancer cells is associated with mutation of p53

We previously reported that most cancer cell lines constitutively express various cytokines including IL-8. But how IL-8 gene expression is regulated in cancer cells is still unclear. p53 tumor suppressor gene plays an important role in the regulation of transcription and is mutated in cancer cell lines. We investigated whether p53 status affects the constitutive expression of IL-8 in human cancer cells. SUIT-2 and RERF-LCOK cancer cells constitutively produced high levels of IL-8 in culture medium. Both cell lines were shown to carry a p53 mutation, and constitutive NF-kappaB transcriptional activity. To analyze whether p53 status mediates IL-8 expression, the effect of wild-type p53 (wt-p53) gene transfer on activation of NF-kappaB was determined in both cell lines. ELISA showed that the IL-8 concentration in medium decreased dose dependently by transient expression of wt-p53. Western-blot analysis showed no marked change in NF-kappaB protein levels in cell nuclei. EMSA showed no repression of NF-kappaB binding activity after transient expression of wt-p53. In contrast, luciferase reporter studies indicated that transcriptional activity of NF-kappaB is suppressed by transfection of wt-p53. These results show that wt-p53 gene transfer inhibits IL-8 production and NF-kappaB transcription activity in cancer cells and suggest that constitutive IL-8 production in cancer cells is associated with mutation of p53.

Total hip arthroplasty: the relationship between posterolateral reconstruction, abductor muscle strength, and femoral offset

PURPOSE

To evaluate the relationship between posterolateral reconstruction, abductor muscle strength, and femoral offset following total hip arthroplasty.

METHODS

Of 28 patients (56 limbs) we assessed, 12 underwent posterolateral reconstruction (reconstruction group) and 16 did not (non-reconstruction group). Isometric abductor muscle strength was measured with a handheld dynamometer. Each patient's muscle strength was converted into a force to body weight ratio, and this ratio was used in the comparisons.

RESULTS

The reconstruction group showed a higher value in abductor muscle strength than the non-reconstruction group (p<0.05). Significant correlation between abductor muscle strength and femoral offset was found in the reconstruction group (p=0.016; r=0.674).

CONCLUSION

Posterolateral reconstruction and appropriate reconstruction of femoral offset following total hip arthroplasty are important to improve the abductor muscle strength.

[Complete response (CR) in a case of advanced hepatocellular carcinoma by percutaneous multi-ablation therapy]

A 56-year-old male patient was diagnosed with hepatocellular carcinoma by abdominal ultrasonography. The tumor was located in segment 7-1 and was 7 cm in diameter. Two transcatheter arterial chemoembolizations (TACE) were not effective. The patient had experienced more than ten fractures because of fibrous dysplasia of the bone. Laparotomy was very risky, so we decided to perform multi-ablation therapy. This therapy consists of percutaneous radiofrequency ablation (RFA) and percutaneous ethanol injection therapy (PEIT). PEIT was applied to the lesion where extrahepatic the Glisson's capsule was near the tumor. After two sessions with these therapies, the tumor with the surrounding liver parenchyma turned necrotic. A complete response was obtained and the patient has been disease-free for 6 months. We conclude that our multi-ablation therapy is effective for patients with advanced hepatocellular carcinoma who have therapeutic limitations because of some preoperative complications.

[A promising new treatment strategy for advanced hepatocellular carcinoma--"multi-ablation therapy" consisting of radio-frequency ablation (RFA), microwave coagulation therapy (MCT) and ethanol injection therapy (EIT)]

We introduce a new treatment strategy (multi-ablation therapy) for advanced hepatocellular carcinoma (HCC). The therapy consists of radio-frequency ablation (RFA), microwave coagulation therapy (MCT) and ethanol injection therapy (EIT). We assessed the efficacy of the therapy in 20 patients with advanced HCCs, including 10 patients with stage III and 10 patients with stage IV. The average tumor diameter was 3.6 cm (max: 6.6 cm) and the average tumor number was 3.6 (max: 11). RFA, MCT and EIT were performed in 20, 14 and 9 cases, respectively. A percutaneous, endoscopic and open approach was applied in 2, 11 and 7 cases, respectively. The average number of times treated on initial admission was 1.1. The response rate, calculated by the tumor necrosis effect, was 100%. The cumulative two-year recurrent rate in the treated sites was 33% and the 2-year cumulative survival rate was 90%. Complications were encountered in two patients (liver failure and pyothorax). Multi-ablation therapy provides an excellent prognosis for advanced HCC patients whose condition could not be controlled with conventional therapeutic modalities.

[Lymph node excision with laparotomy and chemo-radiation therapy for a hepatocellular carcinoma patient with multiple lymph node metastases]

We reported a case of hepatocellular carcinoma (HCC) with multiple lymph node metastases. The patient was a 67-year-old male with C type liver cirrhosis. He underwent microwave coagulation therapy (MCT) for HCC (5 cm and 1.5 cm) 1.5 years before admission. Abdominal CT scan revealed a well-enhanced tumor (2 cm) in caudate lobe of the liver and excessive lymph node metastases, locating in the inferior phrenic, periportal and para-aortic area. The preoperative serum AFP and AFP-L3 levels were 41.9 ng/ml and 93.1%, respectively. At laparotomy, systematic dissection of the enlarged lymph nodes and MCT of the hepatic tumor was performed. After operation, residual inferior phrenic lymph node was treated with irradiation therapy (total 50.4 Gy). The lymph node showed complete response (CR) for about a year and the AFP-L3 level returned to the normal range. After 9 months, a supra-clavicular lymph node was detected on abdominal CT scan. Irradiation therapy (total 45 Gy) in combination with CDDP (100 mg) and 5-FU (4,000 mg) was applied. The lymph node had been assessed as partial response for 6 months. The patient lived quite well after these therapies, but died of hepatic failure 32 months after the initial operation. In conclusion, we recommend this therapeutic strategy using operative excision and chemo-radiation therapy for HCC with multiple lymph node metastases.

[A case report of advanced hepatocellular carcinoma successfully treated with surgical multi-ablation therapy based on radio-frequency thermal ablation]

We report a patient with advanced hepatocellular carcinoma (HCC) who was successfully treated with multi-ablation therapy by the surgical method of laparotomy and partial thoracotomy. A 67-year-old man, who had undergone transcatheter arterial embolization (TAE) three times for advanced HCC with hepatitis C, presented at our hospital in May 2001. Although TAE had been performed 3 times starting 2 years earlier, interventional therapy for recurrent tumors is difficult because of stenosis and obstruction of regional hepatic arteries. Computed tomography of the liver revealed five tumors in both lobes and the tumor in segment VIII presented difficulty for percutaneous ablation treatment due to its closeness to the trunk of the hepatic vein. Multi-ablation therapy consisting of radio-frequency ablation, microwave ablation and ethanol injection was selected for this patient. By laparotomy and partial thoracotomy, we performed multi-ablation therapy safely and accurately for each tumor. After this treatment, 5 tumors in both lobes showed no viability on dynamic CT and the patency of the right hepatic vein was preserved. Six months after the treatment, one remnant mass appeared in segment V. An additional two sessions of percutaneous RFA were performed for this tumor. At the end of these treatments, enhanced CT revealed no viability of the tumors, and serum alpha-fetoprotein and PIVKA-II level dropped to the normal range. This case suggests that multiple ablation therapy with a surgical method is feasible and useful in cases of advanced hepatocellular carcinoma.

[Efficacy of local ablation therapy for liver metastasis from colorectal cancer--radiofrequency ablation and microwave coagulation therapy]

We evaluated the efficacy of local ablation therapy in 40 patients with liver metastases from colorectal cancer. Radiofrequency ablation (RFA) and/or microwave coagulation therapy (MCT) were used. Ablation therapies were performed in percutaneous, endoscopic, and operative procedures. The regional recurrence rate at the therapeutic sites was 15% (median follow-up period of 2.5 years). The average surgical margin in the operative ablation group was 11 mm. The cumulative 5-year survival rates were 37% in the local ablation, 41% in the hepatic resection, and 5% in the regional chemotherapy groups. Major complications occurred in only two patients (one biliary fistula and one liver abscess). Together these observations indicate that local ablation therapy is a radical and safe locoregional therapy that provides adequate local control and contributes to long survival.

IL-6 and IFN-gamma regulation of IL-10 production by human colon carcinoma cells

IL-10 has been shown to play a crucial role in immunosuppression in cancer patients. We explored the regulation of IL-10 production by TNF-alpha, IL-1 beta, IL-6, IL-8, and IFN-gamma in human colon carcinoma COLO205 cells. Northern analysis revealed a marked expression of IL-10 mRNA after stimulation by IL-6, and a marginal but significant expression by TNF-alpha, IL-1 beta or IFN-gamma. No IL-10 mRNA expression was observed when cells were untreated or incubated with IL-8. IL-10 in the culture supernatants showed good agreement with mRNA expression. In addition, IFN-gamma dose-dependently inhibited this IL-6-induced production of IL-10. MTT assay revealed that low dose IFN-gamma (1-10 ng/ml) had no effect on growth of COLO205 cells, but that high dose IFN-gamma (>100 ng/ml) significantly inhibited their proliferation. Northern analysis of COLO205 cells pretreated with IFN-gamma demonstrated that the IL-6R alpha chain was down-regulated. These results suggest that, in certain colon carcinoma cells, tumor-derived IL-10 production is directly regulated by systemic or local production of pro-inflammatory cytokines, such as IL-6 and IFN-gamma.

Function for p300 and not CBP in the apoptotic response to DNA damage

The cellular response to ionizing radiation (IR) includes the induction of apoptosis. The p300/CBP proteins possess histone acetyltransferase activity and function as transcriptional coactivators of p53. We have prepared cells deficient in p300 or CBP to define the roles of these proteins in the cellular response to DNA damage. The present results demonstrate that p300, but not CBP, contributes to IR sensitivity of cells. The results also demonstrate that IR-induced apoptosis is impaired in the p300-, but not CBP-, deficient cells. These findings indicate that p300 functions in the apoptotic response to DNA damage.

p73 is regulated by tyrosine kinase c-Abl in the apoptotic response to DNA damage

The protein p73 is a structural and functional homologue of the p53 tumour-suppressor protein but, unlike p53, it is not induced in response to DNA damage. The tyrosine kinase c-Abl is activated by certain DNA-damaging agents and contributes to the induction of programmed cell death (apoptosis) by p53-dependent and p53-independent mechanisms. Here we show that c-Abl binds to p73 in cells, interacting through its SH3 domain with the carboxy-terminal homo-oligomerization domain of p73. c-Abl phosphorylates p73 on a tyrosine residue at position 99 both in vitro and in cells that have been exposed to ionizing radiation. Our results show that c-Abl stimulates p73-mediated transactivation and apoptosis. This regulation of p73 by c-Abl in response to DNA damage is also demonstrated by a failure of ionizing-radiation-induced apoptosis after disruption of the c-Abl-p73 interaction. These findings show that p73 is regulated by a c-Abl-dependent mechanism and that p73 participates in the apoptotic response to DNA damage.

Characteristic feature of oxygen cost at simulated laboratory triathlon test in trained triathletes

BACKGROUND

The present study was carried out in order to investigate the respiratory and circulatory features during a simulated laboratory triathlon test in trained triathletes.

METHODS

EXPERIMENTAL DESIGN

Sixteen male triathletes were divided into superior (n = 8) and slower triathletes (n = 8) according to their race time. These subjects performed both maximal exercise tests and a simulated laboratory triathlon test (ST). The latter test consisted of flume-pool swimming for 30 min, ergometer cycling for 75 min and treadmill running for 45 min as a continuous task. The exercise intensity was 60% of VO2 max during swimming, cycling and running, respectively.

RESULTS

In slower triathletes, VO2, minute ventilation (VE), heart rate (HR) and temperature of external auditory canal were increased from an earlier stage compared with those in superior athletes. The percent increase (delta) of VO2, VE and HR between the 10th and last min of cycling and running stages in superior triathletes were significantly smaller than those in slower athletes. The oxygen cost (oxygen uptake/running velocity) of running stage was significantly lower in superior triathletes (0.220 +/- 0.020 ml.kg-1.m-1) compared with slower athletes (0.264 +/- 0.014 ml.kg-1.m-1).

CONCLUSIONS

These results suggest that superior triathletes performed ST more economically than slower athletes and had excellent thermoregulatory adaptation.

Physiological characteristics of well-trained synchronized swimmers in relation to performance scores

The purpose of this study was to examine the relationships between the physiological characteristics of synchronized swimmers and their performance scores. The subjects were 16 trained female synchronized swimmers with a mean age of 17.2 +/- 1.7 years (mean +/- SD). The examined variables were body dimensions (height, width, body mass, circumference of the body and segment length), body composition, isokinetic muscle strength of the elbow and knee during extension and flexion, abdominal muscle endurance, anaerobic power (leg extension power and peak blood lactate concentration), aerobic power (maximum oxygen uptake [VO2max], swimming velocity at the onset of blood lactate accumulation [OBLA-V]), and flexibility (standing trunk flexion, prone trunk extension and distance between the open legs). The performance scores had significant correlations (p < 0.05) with isokinetic muscle strength of the elbow extension and flexion, and the knee extension, abdominal muscle endurance, leg extension power, VO2max x wt(-1), OBLA-V and distance between the open legs. However, no significant correlations were found between the performance scores and anthropometric variables. This study showed that the performance scores of synchronized swimmers correlated significantly with the functional aspects, and that muscle strength, muscle endurance and aerobic capacity seem to be particularly important determinants.

Role for caspase-mediated cleavage of Rad51 in induction of apoptosis by DNA damage

We report here that the Rad51 recombinase is cleaved in mammalian cells during the induction of apoptosis by ionizing radiation (IR) exposure. The results demonstrate that IR induces Rad51 cleavage by a caspase-dependent mechanism. Further support for involvement of caspases is provided by the finding that IR-induced proteolysis of Rad51 is inhibited by Ac-DEVD-CHO. In vitro studies show that Rad51 is cleaved by caspase 3 at a DVLD/N site. Stable expression of a Rad51 mutant in which the aspartic acid residues were mutated to alanines (AVLA/N) confirmed that the DVLD/N site is responsible for the cleavage of Rad51 in IR-induced apoptosis. The functional significance of Rad51 proteolysis is supported by the finding that, unlike intact Rad51, the N- and C-terminal cleavage products fail to exhibit recombinase activity. In cells, overexpression of the Rad51(D-A) mutant had no effect on activation of caspase 3 but did abrogate in part the apoptotic response to IR exposure. We conclude that proteolytic inactivation of Rad51 by a caspase-mediated mechanism contributes to the cell death response induced by DNA damage.

Role for p300 in stabilization of p53 in the response to DNA damage

The nuclear p300/CBP proteins function as coactivators of gene transcription. Here, using cells deficient in p300 or CBP, we show that p300, and not CBP, is essential for ionizing radiation-induced accumulation of the p53 tumor suppressor and thereby p53-mediated growth arrest. The results demonstrate that deficiency of p300 results in increased degradation of p53. Our findings suggest that p300 contributes to the stabilization and transactivation function of p53 in the cellular response to DNA damage.

FUT-175 inhibits the production of IL-6 and IL-8 in human monocytes

We investigated the effect of FUT-175, a serine protease inhibitor, on the production of pro-inflammatory cytokines, interleukin-6 (IL-6) and interleukin-8 (IL-8), by monocytes stimulated with lipopolysaccharide (LPS). Monocytes isolated from healthy volunteers were incubated with LPS and various concentrations of FUT-175 for 12 hours. The productions of both IL-6 and IL-8, measured by enzyme-linked immunosorbent assay, were significantly inhibited by FUT at the concentration of 1 to 100 microg/ml in a dose-dependent manner. Furthermore, the expressions of IL-6 and IL-8 mRNAs were also inhibited by FUT-175. These data suggest that FUT-175 may reduce the pathological inflammatory conditions associated with enhanced production of proinflammatory cytokines including IL-6 and IL-8.

Activation of protein kinase C delta by the c-Abl tyrosine kinase in response to ionizing radiation

The c-Abl protein tyrosine kinase is activated by ionizing radiation (IR) and certain other DNA-damaging agents. The present studies demonstrate that c-Abl associates constitutively with protein kinase C delta (PKCdelta). The results show that the SH3 domain of c-Abl interacts directly with PKCdelta. c-Abl phosphorylates and activates PKCdelta in vitro. We also show that IR treatment of cells is associated with c-Abl-dependent phosphorylation of PKCdelta and translocation of PKCdelta to the nucleus. These findings support a functional interaction between c-Abl and PKCdelta in the cellular response to genotoxic stress.

Regulation of Rad51 function by c-Abl in response to DNA damage

The Rad51 protein, a homolog of bacterial RecA, functions in DNA double-strand break repair and genetic recombination. Whereas Rad51 catalyzes ATP-dependent pairing and strand exchange between homologous DNA molecules, regulation of this function is unknown. The c-Abl tyrosine kinase is activated by ionizing radiation and certain other DNA-damaging agents. Here we demonstrate that c-Abl interacts constitutively with Rad51. We show that c-Abl phosphorylates Rad51 on Tyr-54 in vitro. The results also show that treatment of cells with ionizing radiation induces c-Abl-dependent phosphorylation of Rad51. Phosphorylation of Rad51 by c-Abl inhibits the binding of Rad51 to DNA and the function of Rad51 in ATP-dependent DNA strand exchange reactions. These findings represent the first demonstration that Rad51 is regulated by phosphorylation and support a functional role for c-Abl in regulating Rad51-dependent recombination in the response to DNA damage.

Pro-apoptotic effect of the c-Abl tyrosine kinase in the cellular response to 1-beta-D-arabinofuranosylcytosine

Treatment of cells with the antimetabolite 1-beta-D-arabinofuranosylcytosine (ara-C) and other genotoxic agents is associated with activation of the c-Abl protein tyrosine kinase. The functional role of c-Abl in the response to DNA damage, however, remains unclear. The present studies demonstrate that cells expressing a dominant negative, kinase-inactive c-Abl (K-R) are resistant to killing by ara-C. The expression of c-Abl (K-R) blocked ara-C-induced apoptosis by a mechanism that is at least in part independent of the p53 tumor suppressor. Cells null for c-Abl also exhibited resistance to induction of apoptosis. These findings provide support for a pro-apoptotic function of c-Abl in the response to certain genotoxic drugs.

Inhibition of phosphatidylinositol 3-kinase by c-Abl in the genotoxic stress response

Activation of phosphatidylinositol (PI) 3-kinase by growth factors results in phosphorylation of phosphatidylinositol lipids at the D3 position. Although PI 3-kinase is essential to cell survival, little is known about mechanisms that negatively regulate this activity. Here we show that the c-Abl tyrosine kinase interacts directly with the p85 subunit of PI 3-kinase. Activation of c-Abl by ionizing radiation exposure is associated with c-Abl-dependent phosphorylation of PI 3-kinase. We also show that phosphorylation of p85 by c-Abl inhibits PI 3-kinase activity in vitro and in irradiated cells. These findings indicate that c-Abl negatively regulates PI 3-kinase in the stress response to DNA damage.

Role for E2F in DNA damage-induced entry of cells into S phase

Mammalian cells respond to ionizing radiation (IR) with transient cell cycle arrest and induction of apoptosis. Here we show that IR increases the expression of the E2F-1 transcription factor and the entry of cells into S phase. E2F-1 transactivation function is inhibited by cyclin A-kinase to ensure orderly progression through S phase. However, in contrast to proliferating cells, IR treatment results in down-regulation of cyclin A-kinase. Expression of a dominant negative form of the E2F heterodimeric partner DP-1 confirmed the involvement of E2F in IR-induced S-phase entry. These findings also support opposing signals involving the induction of E2F and the down-regulation of cyclin A-kinase in the IR response.

Five jumps per day increase bone mass and breaking force in rats

The effects of jump training on bone morphological and mechanical properties were investigated in immature bones of female Fischer 344 rats. Five-week-old rats were divided into control or five jump-trained groups comprised of 5-, 10-, 20-, 40-, and 100-jump groups, representing the number of jumps per day. The rats were jump-trained 5 days/week for 8 weeks, and the height of jump was increased to 40 cm progressively. The femur and tibia in the 5-jump group had significantly greater fat-free dry weights per body weight and maximum loads at the fracture tests than those in the control group. The tibia in the 5-jump group also had significantly larger cortical area at the cross-sectional analysis. Although a slight tendency toward increase according to the number of jumps per day was observed, there were few differences in bone morphological and mechanical parameters among the 10-, 20-, and 40-jump groups. The present results indicate that a large number of strains per day is not necessary for bone hypertrophy to develop in rats.

Leukemia inhibitory factor induces apoptosis and proliferation of human carcinoma cells through different oncogene pathways

Leukemia inhibitory factor (LIF) affects the growth of carcinoma cells, and we thus analyzed its underlying mechanisms. Carcinoma cells constitutively express LIF mRNA, and 23 lines (92.0%) and all (100%) of 25 lines express LIF receptor mRNAs of LIFRbeta and gp130, respectively. Exogenous addition of LIF promoted significant cell proliferation in 4 lines (MCF-7, ZR-75-1, Hs-700T and Panc-1) and suppressed cell growth in 3 lines (AZ-521, GBK-1 and HT-29). LIF significantly induced an immediate early response of genes c-fos and junB 3 hr after stimulation, but not of c-jun during the process of proliferation of MCF-7 and Hs-700T cells, with maximum levels at 30-60 min. The cell-cycle-related gene cyclin E was also induced in MCF-7 and Hs-700T cells, whereas cyclinA, cdk2, c-myc, c-myb and p53 mRNAs were not induced. On the other hand, LIF inhibited growth and increased the rate of cell death of AZ-521 and GBK-1 cells. LIF increased the number of TUNEL-positive cells in AZ-521 cells and DNA fragmentation in AZ-521 and GBK-1 cells. LIF induced apoptosis related genes c-myc and ICE during suppression of cell growth, but p53, p21, c-fos, cyclin A and cyclin E were not induced. Our results suggest that LIF is linked to cell proliferation and apoptosis in some human carcinoma cell lines. It is considered that this is related to differences in signal transduction and induction of oncogenes.

Evidence that eosinophil infiltration in the OK-432/fibrinogen-injected Meth-A tumor in mice is mediated by locally produced IL-5

It was previously demonstrated that a single injection of OK-432 (a penicillin-treated freeze-dried Streptococcus) mixed with fibrinogen into cancer tissues induces marked infiltration by eosinophils of the tumor stroma and leads to tumor necrosis. In the present study, we examined mechanisms regulating the local accumulation of eosinophils and the role of infiltrating eosinophils in tumor regression using the OK-432/fibrinogen injected Meth-A fibrosarcoma tumor. After injection of OK-432/fibrinogen into the tumor on the left flank of the BALB/c mice, eosinophil infiltration became obvious in the tumor stroma on day 3 following the accumulation of macrophages and neutrophils, was massive on day 5 and decreased by day 10. After the decrease in the infiltration of eosinophils, the tumor injected with OK-432/fibrinogen diminished markedly in size with ulceration as compared with control. Northern blot analysis revealed that expression of IL-5 mRNA in the tumor tissue was not detected on day 0, was significantly on day 3, reached the maximum on day 5, and thereafter decreased by day 10. Although intraperitoneal injection of rat anti-IL-5 monoclonal antibody in tumor bearing mice prior to OK-432 injection inhibited the infiltration of eosinophils, the antitumor effects of OK-432 persisted. In the blood, neither eosinophilia nor IL-5 activity was recognized during the course of the experiment. These results suggest that intratumoral injection of OK-432/fibrinogen induces local production of IL-5, which in turn recruits eosinophils into the tumor tissue, however, the infiltrating eosinophils do not play an important role in tumor regression.

What is the minimum age for applying the forbes equation between body density and body fat to the elderly?

In order to determine the age above which the FORBES equation for calculating percent body fat (%BF) in the elderly is to be applied, 9 persons in their 60s, 7 persons in their 70s and 3 persons older than 80 took part in this study. %BF was measured using dual-energy X-ray absorptiometry (DEXA). In each subject, body density was measured using densitometry. %BF was then calculated by substituting body density for the Siri or FORBES equation. Based on the value of %BF measured with DEXA, the calculated %BF was criticized for each decade of subjects. It was concluded that the Siri equation should be applied to those who are younger than 80 and that the FORBES equation should be applied to those who are 80 and older.

IL-6 and soluble IL-6 receptor levels change differently after surgery both in the blood and in the operative field

To investigate alterations in post-operative levels of IL-6 and soluble IL-6 receptor (sIL-6R), we examined their levels in serum and samples of drainage fluids from 26 patients who underwent thoracoabdominal surgery. Serum IL-6 levels reached the maximum within the first post-operative day and decreased thereafter. The IL-6 levels in the drainage fluid were much higher than in the serum (458 +/- 101-fold; mean +/- SEM) in the early post-operative phase. A large quantity of sIL-6R levels was present in blood samples. The time course of serum sIL-6R levels in 26 patients showed no significant change. sIL-6R concentrations in the drainage fluid were significantly lower than in serum (4.5 +/- 1.1-fold; mean +/- SEM) in the early post-operative phase. We propose that IL-6 is produced in the operative field and enters the peripheral blood stream to induce elevation of serum IL-6. On the other hand, sIL-6R levels in the operative field are lower than in the serum, and the serum sIL-6R levels are not influenced by surgical trauma. These data suggest that sIL-6R is being constantly produced in areas other than the operative field, while sIL-6R level is reduced by consumption in the operative field. Mechanisms to cope with surgical stress, involving sIL-6R together with its ligand IL-6 may thus exist.

Economy during a simulated laboratory test triathlon is highly related to Olympic distance triathlon

This study examined the relationship between Olympic distance triathlon (swim over 1.5 km, cycle over 40.0 km, and run over 10.0 km) and economy during a simulated laboratory test triathlon. Seventeen male triathletes conducted both maximal exercise tests and simulated laboratory triathlon. The latter test consisted of swimming (S), cycling (C) and running (R) stages as a continuous task using a flume-pool, a cycle ergometer and a treadmill, respectively. The exercise intensity and duration were 60% of VO2max during swimming, cycling and running for 30, 75 and 45 min, respectively. The index of economy was determined by the % VO2max at the last min of each stage during a simulated laboratory test triathlon. Results indicated that Olympic distance triathlon (total time) was correlated to swimming-VO2max (r = -0.621, p < 0.001), cycling-VO2max (r = -0.873, p < 0.001), running-VO2max (r = -0.891, p < 0.001), S-Economy (r = 0.208, ns), C-Economy (r = 0.601, p < 0.001) and R-Economy (r = 0.769, p < 0.001). There were also significant correlations between swimming time and swimming-VO2max (r = -0.648, p < 0.01), between cycling time and cycling-VO2max (r = -0.819, p <0.001), between running time and running-VO2max (r = -0.726, p < 0.001), between swimming time and S-Economy (r = 0.550, p < 0.05), between cycling time and C-Economy (r = 0.613, p < 0.01), and between running time and R-Economy (r = 0.548, p < 0.05). These results demonstrated that the larger VO2max during maximal exercise tests and smaller increment of VO2 during a simulated laboratory test triathlon indicating good economy were good predictors to determine the Olympic distance triathlon.

Regulation of DNA damage-induced apoptosis by the c-Abl tyrosine kinase

Activation of the c-Abl protein tyrosine kinase by certain DNA-damaging agents contributes to downregulation of Cdk2 and G1 arrest by a p53-dependent mechanism. The present work investigates the potential role of c-Abl in apoptosis induced by DNA damage. Transient transfection studies with wild-type, but not kinase-inactive, c-Abl demonstrate induction of apoptosis. Cells that stably express inactive c-Abl exhibit resistance to ionizing radiation-induced loss of clonogenic survival and apoptosis. Cells null for c-abl are also impaired in the apoptotic response to ionizing radiation. We further show that cells deficient in p53 undergo apoptosis in response to expression of c-Abl and exhibit decreases in radiation-induced apoptosis when expressing inactive c-Abl. These findings suggest that c-Abl kinase regulates DNA damage-induced apoptosis.

Kupffer cell production of cytokine-induced neutrophil chemoattractant following ischemia/reperfusion injury in rats

We investigated the role of hepatic macrophages in the inflammatory response following reperfusion injury by blocking Kupffer cell phagocytosis with gadolinium chloride (GdCl3). Liver ischemia was induced in rats by occluding the portal vein for 30 minutes. A bolus of GdCl3 (7 mg/kg) was injected intravenously 1 and 2 days before surgery. The serum levels of cytokine-induced neutrophil chemoattractant (CINC) in untreated rats increased following reperfusion, peaked after 6 hours, and then gradually decreased. GdCl3 or heparin alone significantly decreased the serum levels of CINC (P < .05). In addition, pretreatment with GdCl3/heparin further inhibited the rise in the serum levels of CINC following reperfusion compared with those in untreated animals (P < .01). The in vitro production of CINC by Kupffer cells, obtained from animals pretreated with heparin or GdCl3, was significantly lower than that of cells isolated from untreated animals. Pretreatment with GdCl3/heparin further decreased CINC production by Kupffer cells compared with that of cells from animals that were pretreated with heparin or GdCl3 alone. The expression of CINC transcripts in Kupffer cells or in liver tissue peaked 3 hours after reperfusion in untreated animals. Pretreatment with heparin, GdCl3, or both significantly decreased the levels of CINC messenger RNA (mRNA) transcripts. Pretreatment with heparin, GdCl3, or GdCl3/heparin significantly decreased the number of neutrophils that accumulated in the liver 24 hours following reperfusion, compared with those in untreated animals. These results suggest that Kupffer cells release CINC and may play an important role in early neutrophil infiltration into the liver following ischemia/reperfusion.

Suppression of in vivo tumor growth by the transfection of the interleukin-5 gene into colon tumor cells

To investigate the influence of tumor producing interleukin-5 (IL-5) on growth kinetics of tumors, we transduced the murine IL-5 gene into murine colon C26 tumor cells. Two IL-5-secreting clones, low-level IL-5 producer C26-8B and high-level IL-5 producer C26-6F, were established. Both tumors, C26-6F and C26-8B, grew more slowly than the mock C26 tumor, although the in vitro growth rate of these IL-5 transfectants was much the same as that of the mock C26 cells. There was a significantly decreased number of colonies in the lung of mice given C26-6F or C26-8B tumors i.v. than in mice given mock C26 tumors i.v. Moreover, in mice given C26-6F cells i.v., a smaller number of tumor colonies in the lung was observed, as compared to the case with C26-6B cells. While the growth rate of C26-8B tumors in mice treated with anti-IL-5 mAb was more rapid than that seen in control mAb-treated mice, growth of C26-6F tumors in anti-IL-5-mAb-treated mice was slightly more rapid compared to findings in control mAb-treated mice. The isotype-matched mAb did not alter the in vitro growth of mock-C26 cells or of the IL-5-gene-modified C26 cells. Growth of IL-5-secreting C26 tumors transplanted in nude mice was also inhibited. These results suggest that tumor-producing IL-5 inhibits growth of colon tumors mediated through T-cell-independent protective mechanisms of the host.

Effects of jump training on bone hypertrophy in young and old rats

The effects of jump training on bone hypertrophy were investigated in 3, 6, 12, 20 and 27 month-old female Fischer 344 rats. The rats of all age groups were divided into jump training (height: 40 cm, 100 times/day, 5 days/wk for 8 wk), run training (speed: 30 ml/min, 1 h/day, 5 days/wk for 8 wk) or sedentary group. Fat-free dry weights (FFW) of the femur and the tibia were significantly greater in the jump-trained rats than in the run-trained rats, and were significantly greater in the run-trained rats than in the sedentary rats. Jump training significantly increased FFW of the femur and the tibia not only in young rats but also in old rats, while run training did not increase FFW significantly in old rats. In young rats, both jump training and run training significantly increased the length of the femur and the tibia and the diameter of the femur. The diameter of the tibia was greater in the jump-trained rats than in the sedentary and the run-trained rats in all age groups. The results of the present study indicate that jump training was a more effective training mode than run training for bone hypertrophy and that the effects were not limited by age.

Fibroblast-tumor interaction changes constitutive expression of IL-6 and IL-8 in human carcinoma-cells

To examine whether expression of interleukin-6 (IL-6) and interleukin-8 (IL-8) in human carcinoma cells can be influenced by host fibroblasts, we investigated the expression of IL-6 and IL-8 mRNA in carcinoma cells cocultured with fibroblasts. Four human cancer cell lines, NUGC3 and GaCa gastric carcinoma cells, RERF-LCOK lung carcinoma cells, and GBK-1 gallbladder carcinoma cells, which constitutively express large amounts of both IL-6 and IL-8, were cocultured with murine 3T3 fibroblasts, in which IL-6 and IL-8 were not detected, under the same conditions. By Northern blot analysis, the expression of IL-6 mRNA was significantly decreased in NUGC3, GBK-1, and RERF-LCOK cells but was increased in GaCa cells. The expression of IL-8 mRNA was significantly increased in GaCa and GBK-1 cells but decreased in RERF-LCOK cells. Using cell-free conditioned medium, only the NUGC3-3T3 culture supernatant showed little effect on IL-6 and IL-8 mRNA expression in the NUGC3 cells, thereby suggesting that changes in IL-6 and IL-8 mRNA expression observed in the coculture experiment depended mainly on 3T3-NUGC3 contact and not on soluble factors. Similar changes in IL-6 and IL-8 mRNA expression were noted when NUGC3 cells were cultured with paraformaldehyde-fixed 3T3 cells or the 3T3 membrane fraction, thereby supporting this notion. Northern blot analysis of transplanted NUGC3 tumors in nude mice showed a decrease in IL-6 mRNA expression and augmentation of IL-8 mRNA expression. Sera from the NUGC3-bearing mice showed only small differences in IL-6 and IL-8. The downregulation of IL-6 mRNA was reversed 20 hours after NUGC3 cancer cells were separated from the in vivo grown NUGC3 tumors and cultured in vitro. These results suggest that tumors producing IL-6 or IL-8 can be differently modulated by the host cell-mediated pathways, such as contact between fibroblast and tumor cells.

Carcinoma-cells express IL-8 and the IL-8 receptor - their inhibition attenuates the growth of carcinoma-cells

We investigated the expression of IL-8 and the IL-8 receptor (IL-8R) in human carcinoma cells and the role of IL-8 and IL-8R in the growth of carcinoma cells. IL-8 mRNA was detected in 16 of 20 (80%) carcinoma cell lines and 20 of 24 (83.3%) cancer tissues by Northern blot analysis. IL-8R mRNA was expressed in 7 of 11 (63.6%) carcinoma cell lines by reverse transcriptase polymerase chain reaction (RT-PCR). Neutrophil chemotactic activity in the culture supernatant of carcinoma cell lines correlated with immunoreactive IL-X concentration. Growth of carcinoma cells was significantly inhibited in the presence of anti-IL-8 antibody or IL-8R antisense oligonucleotide. These results revealed that IL-8 and IL-8R are expressed in the majority of carcinoma cells and suggest that they might play a role in the growth of carcinoma cells.

Human carcinoma cell lines produce biologically active leukemia inhibitory factor (LIF)

We investigated the production of leukemia inhibitory factor (LIF) by human carcinoma cell lines. LIF mRNA was detected by Northern blot analysis in all 24 carcinoma cell lines of the lung, breast, stomach, colon, liver, gallbladder, pancreas and melanocytes. Seventeen of them (70.8%) secreted LIF in the culture supernatant (range: 40.4-3990.3 pg/ml, mean +/- SEM: 611.8 +/- 262.9 pg/ml). Biologic activity of LIF was confirmed in the culture supernatant of carcinoma cell lines by the MTT assay using M1 cells. The present results showed that human carcinoma cell lines are constitutively producing biologically active LIF. The possible biological significance of LIF produced by cancer cells is discussed.

Humoral factors derived from glial cells protect cultured neuroblastoma cells against glutamate toxicity

The protective effects of glial cells against glutamate cytotoxicity on neuronal cells were studied using clonal neuroblastoma cells and two types of glial cells. Neuronal cells treated with glia-conditioned medium became able to tolerate glutamate toxicity. It is suggested that the preparatory processes against glutamate toxicity might be developed in neurons by the humoral factor(s) released from glial cells.

Elevation of circulating interleukin 6 after surgery: factors influencing the serum level

To investigate the effect of surgical trauma and other factors on the postoperative elevation of serum interleukin 6 (IL-6), we examined changes in IL-6 concentration after major thoracoabdominal surgery. Serum IL-6 levels reached the maximum concentration on the first postoperative day in all 38 patients, with peak ranging from 1400.8 +/- 383.4 pg/ml (mean +/- SEM) to 29.8 +/- 3.8 among six groups who underwent surgery at different sites. The IL-6 peak was significantly correlated with surgical trauma as defined by the operation length and the volume of blood loss during surgery (r = 0.554, P < 0.01 and r = 0.427, P < 0.01, respectively). The peak concentration of serum IL-6 in patients undergoing esophagectomy was significantly higher than in those undergoing pancreaticoduodenectomy (P < 0.05), despite a similar degree of surgical trauma defined by the operation length and volume of blood loss during surgery. Peak IL-6 concentration observed in a patient who underwent esophagectomy was about 100-fold greater in fluid drained from the thorax than in the peripheral blood. IL-6 mRNA was demonstrated in leukocytes from thoracic and abdominal exudate at 6, 24 and 48 h after surgery. In contrast, IL-6 mRNA could not be detected in leukocytes from the peripheral blood. Similar findings were also observed for interleukin 8 (IL-8). However, interleukin 1 beta (IL-1 beta) and tumour necrosis factor-alpha (TNF-alpha) were detected only once after surgery in the drainage fluid.(ABSTRACT TRUNCATED AT 250 WORDS)