Gefitinib ('Iressa', ZD1839) may restore chemosensitivity in NSCLC patients?

Gefitinib ('Iressa, ZD1839) has promising antitumor activity in non-small cell lung cancer (NSCLC). However, patients with advanced NSCLC have few treatment options available if they are refractory to gefitinib. We describe four cases of patients with advanced NSCLC who previously responded to gefitinib and obtained significant tumor regression through retreatment with other cytotoxic agents. Gefitinib might restore chemosensitivity to previously chemorefractory patients.

An overview of 48 elderly-specific clinical trials of systemic chemotherapy for advanced non-small cell lung cancer

PURPOSE

The aim of the present study was to identify elderly-specific clinical trials for advanced non-small cell lung cancer (NSCLC) and to clarify the study design and patient characteristics entered of each of these trials.

METHODS

We used the MEDLINE database to select prospective clinical trials evaluating the efficacy of chemotherapy in elderly patients with advanced NSCLC.

RESULTS

Our literature search yielded 48 prospective clinical trials between 1990 and 2003, involving a total of 2648 elderly patients with advanced NSCLC. The median number of patients treated per trial was 36. In 23 (48%) of the 48 trials, only the abstract was available. In 44 trials (92%), elderly patients were defined using their calendar age, and the age of 70 years was the most frequently used lower limit for inclusion. Vinorelbine was the most widely studied chemotherapy agent in elderly patients.

CONCLUSIONS

Our review revealed that (i) the definition of "elderly" varied from trial to trial, and elderly patients were simply defined using calendar age in the clinical trials; (ii) the quality of elderly-specific trials were generally poor, mainly because of their small sample size.

Role of Adjuvant Chemotherapy in Patients With Resected Non–Small-Cell Lung Cancer: Reappraisal With a Meta-Analysis of Randomized Controlled Trials

Purpose

The role of adjuvant chemotherapy in patients with resected non–small-cell lung cancer (NSCLC) remains to be defined. This study was aimed at re-evaluating the effectiveness of adjuvant chemotherapy in patients with resected NSCLC, by performing a meta-analysis of relevant trials.

Methods

We performed a literature search to identify trials reported after the publication of a meta-analysis in 1995, comparing patients with NSCLC receiving chemotherapy after surgery with those undergoing surgery alone. The hazard ratio (HR) was estimated to assess the survival advantage of adjuvant chemotherapy.

Results

Eleven trials conducted on a total of 5,716 patients were identified by the literature search. In these trials, hazard ratio estimates suggested that adjuvant chemotherapy yielded a survival advantage over surgery alone (HR, 0.872; 95% CI, 0.805 to 0.944; P = .001). In a subset analysis, both cisplatin-based chemotherapy (HR, 0.891; 95% CI, 0.815 to 0.975; P = .012) and single-agent therapy with tegafur and uracil (UFT; HR, 0.799; 95% CI, 0.668 to 0.957; P = .015) were found to yield a significant survival benefit. The toxicities of adjuvant chemotherapy were found to be generally mild.

Conclusion

This is the first updated meta-analysis demonstrating the importance of cisplatin-based chemotherapy and single-agent UFT therapy as adjuvant chemotherapy in the treatment of resected NSCLC. Although the results must be carefully interpreted because of one limitation (the meta-analysis was performed with abstracted data), they raise critical issues that must be resolved in future studies.

A phase I study and pharmacokinetics of irinotecan (CPT-11) and paclitaxel in patients with advanced non-small cell lung cancer

PURPOSE

To determine the maximum-tolerated dose (MTD) of irinotecan and paclitaxel in this two-drug combination, and to investigate a sequence-dependent effect in the pharmacokinetics of these drugs, we conducted a phase I study in chemo-naïve patients with advanced non-small cell lung cancer (NSCLC).

PATIENTS AND METHODS

Patients with stage IIIB/IV NSCLC were enrolled in this study. Both irinotecan and paclitaxel were administered on days 1 and 8, and repeated every 3 weeks. The starting dose of both drugs was 40 mg/m2 which was then alternately increased by 10 mg/m2 increments. In the first cycle, irinotecan was initially administered and followed by paclitaxel infusion, while the sequence of drug administration was reversed in the second cycle. Blood samples for pharmacokinetic analysis were obtained on day 1 of the first and second cycles.

RESULTS

Nine patients received a total of 12 cycles, which were evaluated for toxicity and efficacy. The main hematological toxicity was neutropenia. Grades 3 or more neutropenia was observed in 67% of cycles at dose level 2. The main non-hematological toxicities were grade 3 febrile neutropenia, supraventricular arrhythmia, and grade 2 hepatic dysfunction. The MTD of irinotecan and paclitaxel were 40 and 50 mg/m2, respectively. In the pharmacokinetic analysis, the maximum concentration of paclitaxel was elevated in a dose-dependent manner. There was a trend toward elevation of the area under the plasma concentration-time curve (AUC) of irinotecan and a decline of the AUC of paclitaxel in cycle 1 (irinotecan followed by paclitaxel), compared with those in cycle 2 (paclitaxel followed by irinotecan). Hepatic toxicity was strongly associated with the AUC of irinotecan (r = 0.894, P < 0.0001). The objective response was not observed in the nine patients.

CONCLUSION

The combination of irinotecan and paclitaxel with this schedule produced considerable toxicities without any antitumor effect for advanced NSCLC. The different schedule of administration or other combinations should be investigated.

Meta-analysis of randomized clinical trials comparing Cisplatin to Carboplatin in patients with advanced non-small-cell lung cancer

PURPOSE

It remains undetermined whether cisplatin and carboplatin are equally effective for advanced non-small-cell lung cancer (NSCLC). We therefore did a meta-analysis of trials that compared cisplatin-based chemotherapy with carboplatin-based chemotherapy.

METHODS

We performed a literature search to identify trials that had investigated the substitution of carboplatin for cisplatin in the treatment of advanced NSCLC. We evaluated these trials for inclusion, rated methodologic quality, and abstracted relevant data.

RESULTS

Of 1,191 reports, eight trials (2,948 patients) were identified, five of which investigated drug regimens containing platinum plus a new agent. Cisplatin-based chemotherapy produced a higher response rate, but the survival advantage was not significant (hazard ratio = 1.050; 95% CI, 0.907 to 1.216; P =.515). Subgroup analysis revealed that combination chemotherapy consisting of cisplatin plus a new agent yields 11% longer survival than carboplatin plus the same new agent (hazard ratio = 1.106; 95% CI, 1.005 to 1.218; P =.039). Patients on cisplatin-based chemotherapy frequently developed nausea and vomiting; thrombocytopenia was more frequent during carboplatin-based chemotherapy. No significant difference in treatment-related mortality was observed.

CONCLUSION

We found that combination chemotherapy consisting of cisplatin plus a new agent yields a substantial survival advantage compared with carboplatin plus a new agent in patients with advanced NSCLC, although we failed to find any survival difference in an analysis that included both new and old agents. The strength of our conclusion is limited because we used abstracted data, and careful interpretation is thus required. Nevertheless, our results raise a critical point that needs to be evaluated in future studies.

Study of paclitaxel and dose escalation of cisplatin in patients with advanced non-small cell lung cancer

BACKGROUND

We conducted a dose-finding and feasibility study in which we administered a fixed dose 3-h infusion of paclitaxel and an escalating dose of cisplatin in Japanese patients with advanced non-small cell lung cancer.

METHODS

Chemotherapy consisted of fixed dose (210 mg/m(2)) paclitaxel given over 3 h on day 1 and an escalating dose of cisplatin on day 2, every 3-4 weeks. The dose of cisplatin was 40 mg/m(2) at level 1, 60 mg/m(2) at level 2 and 80 mg/m(2) at level 3.

RESULTS

Between October 1999 and February 2001, 24 patients were enrolled and 58 cycles were administered. The major hematological toxicities were leukopenia and neutropenia. Grade 4 neutropenia developed in 83.3%, 66.7% and 83.3% of patients at the dose levels of 1, 2 and 3, respectively. The major non-hematological toxicities consisted of alanine aminotransferase (ALT) elevation and peripheral neuropathy. Grade 3 ALT elevation was observed in two of the 12 patients at level 3, but both recovered within 3 days. The peripheral neuropathy was sensory-dominant and frequent, and it was almost tolerable. The maximum tolerated dose was not identified even at the highest dose of paclitaxel (210 mg/m(2)) and cisplatin (80 mg/m(2)) administered in the study. The recommended dose was determined to be paclitaxel 210 mg/m(2) on day 1 and cisplatin 80 mg/m(2) on day 2, every 3-4 weeks. Seven partial responses were observed in the 24 patients.

CONCLUSIONS

The combination of paclitaxel 210 mg/m(2) and cisplatin 80 mg/m(2) was found to be a well-tolerated active regimen in Japanese patients with advanced non-small cell lung cancer.

Successful treatment of limited disease-small cell lung cancer with multimodality treatment consisting of concurrent chemoradiotherapy, high-dose chemotherapy with autologous peripheral blood stem cell transplantation and surgical resection

A 65-year-old man with limited disease-small cell lung cancer was treated with concurrent chemoradiotherapy which resulted in a partial response. He further received high-dose chemotherapy with autologous peripheral blood stem cell transplantation. Development of non-small cell carcinoma was, however, suspected at a site of the residual nodule in cytological examination using bronchoscopy. He then underwent lobectomy, which revealed that the nodule was composed of necrotic tissue. He has been alive without recurrence for seven years. This multimodality treatment appeared to be effective for this patient. However, further investigation is necessary to clarify the role of multimodality treatment.

Distant Failure after Treatment of Postoperative Locoregional Recurrence of Non-Small Cell Lung Cancer

BACKGROUND

The standard treatment for patients with locoregional recurrence of non-small cell lung cancer (NSCLC) after complete resection has not been established. The aim of this study was to evaluate clinicopathologic characteristics, type of locoregional recurrence, pattern of subsequent failure, and survival after the recurrence.

METHODS

Of 743 patients undergoing pulmonary resection for NSCLC in the National Cancer Center Hospital between 1990 and 1995, we retrospectively reviewed the medical charts of the 43 patients (5.8 %) found to have locoregional recurrence without distant metastasis or pleural or pericardial involvement.

RESULTS

The median time to locoregional recurrence was 13.6 months (range: 1.6 - 85.8 months). The most frequent site of recurrence was the mediastinal nodes in 21 of 43 patients (49 %). 33 patients (77 %) received further treatment for the recurrence: thoracic irradiation in 26, surgery in two, systemic chemotherapy in two, and a combination of the above in 3 patients. Subsequent distant failure was detected in 26 (68 %) of the 38 patients assessable for the analysis of failure pattern: lung in 11, brain in 6, bone in 5, and others in 13. The median interval from the recurrence to distant failure was 8.4 months (range: 1.7-56.4 months). The median survival time after diagnosis of the locoregional recurrence was 10.5 months (range: 0-74.0 months). A multivariate analysis showed that local therapy for the locoregional recurrence had no significant impact on postrecurrent survival or distant failure-free survival.

CONCLUSIONS

Many patients with postoperative locoregional recurrence developed distant metastases early after the first recurrence. Systemic chemotherapy in addition to local therapy may be of benefit in this population.

Nocardial Infections in Japan from 1992 to 2001, Including the First Report of Infection by Nocardia transvalensis

In the period from 1992 to 2001, 303 cases of nocardioses were diagnosed in Japan, with the corresponding etiological agents isolated and characterized. Taxonomic analyses of these 303 strains showed that most nocardial infections were caused by members of the Nocardia asteroides group (72.3%). Speciation showed that 72 strains were N. asteroides, 31 strains were N. cyriacigeorgica, 2 strains were N. beijingensis, 81 strains were N. farcinica, and 33 strains were N. nova. Sixty-six strains of N. brasiliensis were the next most prevalent species of the total Nocardia isolates, followed by 14 strains of N. otitidiscaviarum. Infections by N. transvalensis (3 strains) and N. pseudobrasiliensis (1 strain) were also confirmed. The infections due to N. transvalensis, N. cyriacigeorgica, and N. beijingensis were the first reported in Japan. The most common factor that predisposed individuals to nocardial infection in Japan was therapy by immunosuppressive agents (22.4%), including SLE therapy (3.6%), followed by cancer (6.6%), diabetes (3.6%) and AIDS (2.0%). Nocardial infections occurred more commonly in the elderly, with most of the patients between the ages of 61 and 80 years of age. No significant difference regarding infectivity levels between the sexes was observed.

Phase I/II study of 3-week cycle cisplatin-gemcitabine in advanced non-small cell lung cancer

BACKGROUND

The combination of cisplatin and gemcitabine is one of the most active chemotherapy regimens against non-small cell lung cancer. However, the optimum schedule for this combination has not been determined. This study was performed to determine the maximum tolerated dose of gemcitabine combined with cisplatin in a 3-week cycle regimen and to observe safety and efficacy for Japanese patients with advanced non-small cell lung cancer.

METHODS

80 mg/m(2) of cisplatin on day 1 and escalated doses of gemcitabine on days 1 and 8 were administered every 3 weeks to patients with previously untreated, advanced non-small cell lung cancer. The initial dose of gemcitabine was 1000 mg/m(2) and was escalated in 250 mg/m(2) increments.

RESULTS

Twenty-four patients were enrolled between March and December 2000. In total, 64 courses were given. The main toxicities were neutropenia, thrombocytopenia and hepatotoxicity. The maximum tolerated dose was determined to be 1500 mg/m(2) of gemcitabine combined with 80 mg/m(2 )of cisplatin. Nine of 24 patients (37.5%) achieved a partial response.

CONCLUSION

This study demonstrates that the combination of cisplatin and gemcitabine repeated every three weeks is tolerable for Japanese patients with advanced non-small cell lung cancer. We determined 1250 mg/m(2) of gemcitabine combined with 80 mg/m(2 )of cisplatin to be the recommended dose.

Enhancement of the aquaporin adipose gene expression by a peroxisome proliferator-activated receptor gamma

The current study demonstrates that aquaporin adipose (AQPap), an adipose-specific glycerol channel (Kishida, K., Kuriyama, H., Funahashi, T., Shimomura, I., Kihara, S., Ouchi, N., Nishida, M., Nishizawa, H., Matsuda, M., Takahashi, M., Hotta, K., Nakamura, T., Yamashita, S., Tochino, Y., and Matsuzawa, Y. (2000) J. Biol. Chem. 275, 20896-20902), is a target gene of peroxisome proliferator-activated receptor (PPAR) gamma. The AQPap mRNA amounts increased following the induction of PPARgamma in the differentiation of 3T3-L1 adipocytes. The AQPap mRNA in the adipose tissue increased when mice were treated with pioglitazone (PGZ), a synthetic PPARgamma ligand, and decreased in PPARgamma(+/-) heterozygous knockout mice. In 3T3-L1 adipocytes, PGZ augmented the AQPap mRNA expression and its promoter activity. Serial deletion of the promoter revealed the putative peroxisome proliferator-activated receptor response element (PPRE) at -93/-77. In 3T3-L1 preadipocytes, the expression of PPARgamma by transfection and PGZ activated the luciferase activity of the promoter containing the PPRE, whereas the PPRE-deleted mutant was not affected. The gel mobility shift assay showed the direct binding of PPARgamma-retinoid X receptor alpha complex to the PPRE. DeltaPPARgamma, which we generated as the dominant negative PPARgamma lacking the activation function-2 domain, suppressed the promoter activity in 3T3-L1 cells, dose-dependently. We conclude that AQPap is a novel adipose-specific target gene of PPARgamma through the binding of PPARgamma-retinoid X receptor complex to the PPRE region in its promoter.

The loss of susceptibility to apoptosis in exudated tissue neutrophils is associated with their nuclear factor-kappa B activation

Tissue neutrophils, human salivary neutrophils donated from healthy subjects and synovial fluid neutrophils collected from patients with rheumatoid arthritis were compared with circulating blood neutrophils. Concomitant treatment of circulating blood neutrophils with tumor necrosis factor-alpha (TNF-alpha) and cycloheximide induced neutrophil apoptosis, whereas the same treatment failed to induce significant apoptosis in salivary and synovial fluid neutrophils. Caspase-3 activation by TNF-alpha was observed in these tissue neutrophils, although its activity was significantly weaker than that in circulating blood neutrophils. In circulating blood neutrophils, TNF-alpha induced activation of nuclear factor-kappa B (NF-kappa B), whereas, in tissue neutrophils, NF-kappa B had been already activated without any stimulation, and no further activation was induced by the treatment with TNF-alpha. Furthermore, while pretreatment of neutrophils with an NF-kappa B inhibitor produced typical apoptotic changes in circulating blood neutrophils, this inhibitor did not produce any morphological apoptotic changes induced by TNF-alpha in tissue neutrophils. These results indicate that neutrophils undergo marked functional changes such as altered sensitivity to apoptosis-inducing stimuli in association with their exudation from blood into tissue, and that NF-kappa B activation is involved in the acquisition of resistance to TNF-alpha-induced apoptosis.

Visceral fat is a major contributor for multiple risk factor clustering in Japanese men with impaired glucose tolerance

OBJECTIVE

The significance of abdominal visceral fat accumulation was evaluated in Japanese men with impaired glucose tolerance (IGT).

RESEARCH DESIGN AND METHODS

The IGT subjects (n = 123) were aged 55 +/- 9 years with a BMI of 24 +/- 3 kg/m(2). The 148 control subjects with normal glucose tolerance (NGT) were matched for age and BMI. IGT and NGT were classified according to the 1985 World Health Organization criteria. Abdominal fat distribution was analyzed by computed tomography at umbilical level. Plasma lipid, glucose, and insulin concentrations and blood pressure (BP) were measured.

RESULTS

In subjects with IGT, the average visceral fat area (VFA) was significantly greater than in subjects with NGT. Fasting insulin, the sum of insulin concentrations during an oral glucose tolerance test, insulin resistance according to a homeostasis model assessment for insulin resistance (HOMA-IR), systolic BP, and serum triglyceride were significantly higher, whereas the DeltaI(30-0)/DeltaG(30-0) was significantly lower, in subjects with IGT. Subjects with IGT and NGT were then divided into three subgroups according to the number of risk factors they possessed (dyslipidemia, hypertension, neither, or both). In both IGT and NGT subjects, BMI, VFA, subcutaneous fat area, fasting insulin, HOMA-IR, and insulin secretion of the homeostasis model assessment were significantly higher in the double-risk factor subgroup than in the no-risk factor subgroup, and VFA was a potent and independent variable in association with the presence of a double risk factor.

CONCLUSIONS

Visceral fat accumulation is a major contributor for multiple risk factor clustering in Japanese men with IGT and NGT.

A phase I/II study of cisplatin and vinorelbine chemotherapy in patients with advanced non-small cell lung cancer

BACKGROUND

A combination of cisplatin and vinorelbine chemotherapy is effective in cases of advanced non-small cell lung cancer, but the optimum administration schedule for both drugs has not yet been defined. The aim of this study was to determine the maximum dose of vinorelbine that can be tolerated while receiving a fixed dose of cisplatin every 3 weeks and to observe the response in Japanese patients with advanced non-small cell lung cancer who had not previously received chemotherapy.

METHODS

Cisplatin was given at a dose of 80 mg/m2 on day 1. Vinorelbine was administered on days 1 and 8 at a starting dose of 25 mg/m2 that was then increased by 5 mg/m2 increments. This treatment was repeated every 3 weeks.

RESULTS

Twenty-one patients received a total of 54 chemotherapy cycles consisting of three different vinorelbine dosages. Toxicity and efficacy were evaluated in all of the patients. The main dose-limiting toxicity was neutropenia. Grades 3-4 leukopenia and neutropenia were observed in 57% and 86% of all cycles, respectively. These conditions were reversible and did not result in death from toxicity. The most severe non-hematological toxicity symptom was a grade 3 infection and reaction at the site of injection. The maximum tolerated dose of vinorelbine was 35 mg/m2. The objective response was noted in one of six patients at dose level 1, in four of 12 patients at dose level 2 and in two of three patients at dose level 3.

CONCLUSION

The recommended doses were 80 mg/m2 for cisplatin and 30 mg/m2 for vinorelbine. The combination of cisplatin and vinorelbine repeated every 3 weeks is well tolerated and has shown promising anti-tumor activity against non-small cell lung cancer.

Thiazolidinedione derivative improves fat distribution and multiple risk factors in subjects with visceral fat accumulation--double-blind placebo-controlled trial

BACKGROUND

It has been clarified that visceral fat accumulation leads to atherosclerosis through multiple risk factors such as insulin resistance, glucose intolerance, hyperlipidemia and hypertension. So far, it has been reported that a thaizolidinedione derivative, troglitazone, improves the insulin resistance in subjects with diabetes, glucose intolerance and obesity. However, it has not been reported yet that troglitazone affects fat distribution in subjects concomitant with visceral fat accumulation and multiple risk factors.

METHODS

Twenty-nine subjects with visceral fat accumulation who had at least two risk factors including glucose intolerance, hyperlipidemia and hypertension were investigated. They were randomly assigned to receive either 200 or 400 mg per day of troglitazone or placebo for 12 weeks. A 75 g oral glucose tolerance test (OGTT) was performed before and after the treatment for 12 weeks. Fasting plasma glucose, insulin, HbA(1c), total serum cholesterol (T-chol), triglyceride (TG), HDL-cholesterol (HDL-C), and blood pressure, as well as the number of risk factors were measured periodically during the treatment. The change of the abdominal fat distribution was evaluated using computed tomographic scanning (CT scan) at the umbilicus level.

RESULTS

After the treatment for 12 weeks, the area under the curve (AUC) of plasma glucose from a 75 g OGTT decreased dose-dependently. HbA(1c) and TG decreased significantly in the high-dose troglitazone group (400 mg per day) compared with the placebo group (P<0.05). Systolic blood pressure was significantly lower in subjects with hypertension in the pooled troglitazone group than in the placebo group (P<0.05). Therefore, the number of risk factors decreased with the troglitazone treatment. The ratio of visceral fat area (VFA) to subcutaneous fat area (SFA) (V/S ratio) decreased in the troglitazone groups due to decreased VFA and increased SFA.

CONCLUSION

These results suggest that thiazolidinedione derivative may be a useful drug to improve multiple risk factors by changing the fat distribution in subjects with visceral fat accumulation.

Purification and characterization of alpha-L-fucosidases from Streptomyces sp. OH11242

alpha-L-Fucosidases were found in the culture fluid of Streptomyces sp. OH11242 grown with porcine gastric mucin (PGM) as the sole carbon source. The alpha-L-fucosidases were purified by ammonium sulfate precipitation followed by chromatography on Sepharose CL-4B, hydroxyapatite, Resource Q and Mono Q. Two enzyme fractions, termed Fase-I and Fase-II, were obtained, each bearing different substrate specificity. Fase-I hydrolyzed fucose residues from fucose-containing oligosaccharide chains on PGM, but not p-nitrophenyl alpha-L-fucoside (Fucalpha-O-PNP). In contrast, Fase-II cleaved fucose from Fucalpha-O-PNP, but not fucose-containing oligosaccharides on PGM. Fase-I also hydrolyzed the alpha1-2 fucosidic linkage in various oligosaccharides, but not alpha1-3 and alpha1-4 fucosidic linkages. Fase-II was separated into two fractions, Fase-IIa and -IIb by Mono Q chromatography, Fase-IIb hydrolyzed alpha1-3 and alpha1-4 fucosidic linkages, but not alpha1-2 fucosidic linkages, while Fase-IIa hydrolyzed none of them. Fase-I was purified to homogeneity by SDS-polyacrylamide gel electrophoresis, the molecular mass was estimated to be approximately 59000 and 76000 Da by SDS-PAGE and gel-permeation chromatography, respectively. The optimum pH for Fase-I activity was 5.5-6.0. These fucosidases with different substrate specificities might be useful to reveal the physiological role of fucose-containing oligosaccharides in the gastric mucins.

Differential uptake of grepafloxacin by human circulating blood neutrophils and those exudated into tissues

The uptake of the antimicrobial quinolone agent, grepafloxacin, both by human circulating blood neutrophils and by those exudated into tissues, was evaluated in vitro by comparing the intracellular drug concentrations. In circulating blood neutrophils, the uptake of grepafloxacin was rapid and saturable at 37 degrees C. The uptake of grepafloxacin into circulating blood neutrophils was reduced by lowering the environmental temperature or by the presence of metabolic inhibitors, suggesting the involvement of an active transport mechanism. Furthermore, the uptake of grepafloxacin by tissue (salivary) neutrophils was also partially temperature-dependent and was significantly greater than that by circulating blood neutrophils, i.e. exudation of neutrophils into tissue results in a markedly enhanced transport mechanism for grepafloxacin. This phenomenon may be related to the higher defense activity against infection seen in exudated tissue neutrophils.

Galectin-12, an Adipose-expressed Galectin-like Molecule Possessing Apoptosis-inducing Activity

Galectins constitute a family of proteins that bind to beta-galactoside residues and have diverse physiological functions. Here we report on the identification of a galectin-like molecule, galectin-12, in a human adipose tissue cDNA library. The protein contained two potential carbohydrate-recognition domains with the second carbohydrate-recognition domain being less conserved compared with other galectins. In vitro translated galectin-12 bound to a lactosyl-agarose column far less efficiently than galectin-8. Galectin-12 mRNA was predominantly expressed in adipose tissue of human and mouse and in differentiated 3T3-L1 adipocytes. Caloric restriction and treatment of obese animals with troglitazone increased galectin-12 mRNA levels and decreased the average size of the cells in adipose tissue. The induction of galectin-12 expression by the thiazolidinedione, troglitazone, was paralleled by an increase in the number of apoptotic cells in adipose tissue. Immunocytochemical analysis revealed that galectin-12 was localized in the nucleus of adipocytes, and transfection with galectin-12 cDNA induced apoptosis of COS-1 cells. These results suggest that galectin-12, an adipose-expressed galectin-like molecule, may participate in the apoptosis of adipocytes.

PPARgamma ligands increase expression and plasma concentrations of adiponectin, an adipose-derived protein

Insulin resistance and its dreaded consequence, type 2 diabetes, are major causes of atherosclerosis. Adiponectin is an adipose-specific plasma protein that possesses anti-atherogenic properties, such as the suppression of adhesion molecule expression in vascular endothelial cells and cytokine production from macrophages. Plasma adiponectin concentrations are decreased in obese and type 2 diabetic subjects with insulin resistance. A regimen that normalizes or increases the plasma adiponectin might prevent atherosclerosis in patients with insulin resistance. In this study, we demonstrate the inducing effects of thiazolidinediones (TZDs), which are synthetic PPARgamma ligands, on the expression and secretion of adiponectin in humans and rodents in vivo and in vitro. The administration of TZDs significantly increased the plasma adiponectin concentrations in insulin resistant humans and rodents without affecting their body weight. Adiponectin mRNA expression was normalized or increased by TZDs in the adipose tissues of obese mice. In cultured 3T3-L1 adipocytes, TZD derivatives enhanced the mRNA expression and secretion of adiponectin in a dose- and time-dependent manner. Furthermore, these effects were mediated through the activation of the promoter by the TZDs. On the other hand, TNF-alpha, which is produced more in an insulin-resistant condition, dose-dependently reduced the expression of adiponectin in adipocytes by suppressing its promoter activity. TZDs restored this inhibitory effect by TNF-alpha. TZDs might prevent atherosclerotic vascular disease in insulin-resistant patients by inducing the production of adiponectin through direct effect on its promoter and antagonizing the effect of TNF-alpha on the adiponectin promoter.

The expression of SPARC in adipose tissue and its increased plasma concentration in patients with coronary artery disease

OBJECTIVE

Adipocytes secrete various cytokines and matrix proteins. Several of them precipitate in obesity-associated diseases, including atherosclerosis. In the current study, we have examined the expression of secreted protein, acidic and rich in cysteine (SPARC) in adipose tissue and its significance in obesity and coronary artery disease (CAD).

RESEARCH METHODS AND PROCEDURES

The SPARC mRNA expressions both in vivo and in vitro were detected by Northern blot analysis. Plasma SPARC concentrations were measured by enzyme immunosorbent assay. First, we investigated the plasma SPARC levels of 88 unrelated adult Japanese subjects (62 men and 26 women; average age: [+/- SD] 50 +/- 12 years; body mass index [BMI]: 16 to 46 kg/m(2)). Additionally 31 subjects with CAD diagnosed by coronary angiography (20 men and 11 women) were also investigated.

RESULTS

Human adipose tissues expressed abundant SPARC mRNA. SPARC expression in adipose tissues was upregulated in obese db/db mice. Markedly enhanced expression of SPARC mRNA was observed in 3T3-L1 fibroblasts during adipocyte differentiation. Consistent with these results, plasma SPARC levels proved a positive correlation with BMI in humans (r = 0.27; p < 0.01). Interestingly, plasma SPARC concentrations were significantly elevated in age- and BMI-matched subjects with CAD (p < 0.05).

DISCUSSION

SPARC was expressed in adipose tissues and its expression was enhanced in obese mice. In human, plasma SPARC levels were elevated in obesity and CAD patients. This elevated SPARC may be involved in the progression of CAD.

Hypoadiponectinemia in obesity and type 2 diabetes: close association with insulin resistance and hyperinsulinemia

Plasma concentrations of adiponectin, a novel adipose-specific protein with putative antiatherogenic and antiinflammatory effects, were found to be decreased in Japanese individuals with obesity, type 2 diabetes, and cardiovascular disease, conditions commonly associated with insulin resistance and hyperinsulinemia. To further characterize the relationship between adiponectinemia and adiposity, insulin sensitivity, insulinemia, and glucose tolerance, we measured plasma adiponectin concentrations, body composition (dual-energy x-ray absorptiometry), insulin sensitivity (M, hyperinsulinemic clamp), and glucose tolerance (75-g oral glucose tolerance test) in 23 Caucasians and 121 Pima Indians, a population with a high propensity for obesity and type 2 diabetes. Plasma adiponectin concentration was negatively correlated with percent body fat (r = -0.43), waist-to-thigh ratio (r = -0.46), fasting plasma insulin concentration (r = -0.63), and 2-h glucose concentration (r = -0.38), and positively correlated with M (r = 0.59) (all P < 0.001); all relations were evident in both ethnic groups. In a multivariate analysis, fasting plasma insulin concentration, M, and waist-to-thigh ratio, but not percent body fat or 2-h glucose concentration, were significant independent determinates of adiponectinemia, explaining 47% of the variance (r(2) = 0.47). Differences in adiponectinemia between Pima Indians and Caucasians (7.2 +/- 2.6 vs. 10.2 +/- 4.3 microg/ml, P < 0.0001) and between Pima Indians with normal, impaired, and diabetic glucose tolerance (7.5 +/- 2.7, 6.1 +/- 2.0, 5.5 +/- 1.6 microg/ml, P < 0.0001) remained significant after adjustment for adiposity, but not after additional adjustment for M or fasting insulin concentration. These results confirm that obesity and type 2 diabetes are associated with low plasma adiponectin concentrations in different ethnic groups and indicate that the degree of hypoadiponectinemia is more closely related to the degree of insulin resistance and hyperinsulinemia than to the degree of adiposity and glucose intolerance.

Expression of a specific mucin type recognized by monoclonal antibodies in the rat gastric mucosa regenerating from acetic acid-induced ulcer

BACKGROUND

Detailed research on the healing process of gastric mucosa from injury due to various necrotizing agents is important for regenerating medicine as well as for estimating the quality of ulcer healing. To elucidate this issue, we prepared monoclonal antibodies reacting with mucin molecules present in the specific region and layer of the gastrointestinal mucosa.

METHODS

Acetic acid-induced gastric ulcers were prepared in 8-week-old male Wistar rats. Following 24-h fasting, the animals were killed at 20, 30 and 50 days after acid insult and their stomachs were removed immediately. Serial paraffin sections of the ulcer area were made and immunostained with three distinct monoclonal antibodies. RGM21 and HIK1083 react with mucins derived from the surface mucous cells of the corpus and the gland mucous cells of corpus and antrum, respectively. HCM31 stains sialomucin present in the small intestine and colonic mucosa of rat, but does not react with the intact gastric mucosa, except in the very narrow cardiac gland area.

RESULTS

On the 20th day after ulcer preparation, the cells stained with RGM21 and HIK1083 were restricted only to the surface layer and the bottom layer of regenerating epithelia, respectively. HCN31 staining covered most of the regenerating epithelia. On the 30th day, the staining of HCM31 was enhanced in the regenerating area. Staining of RGM21 did not change, but the HIK1083 stained area increased in the lower part of the regenerating epithelia. On the 50th day, the staining with HCM31 weakened markedly in the lower part, and this area was occupied with HIK1083 positive cells.

CONCLUSION

A notable but temporary expression of a kind of sialomucin specifically stained with HCM31 was observed in the regenerating epithelia during the healing stage of acetic acid-induced gastric damage.

Circulating concentrations of the adipocyte protein adiponectin are decreased in parallel with reduced insulin sensitivity during the progression to type 2 diabetes in rhesus monkeys

Adiponectin is an adipose-specific plasma protein whose plasma concentrations are decreased in obese subjects and type 2 diabetic patients. This protein possesses putative antiatherogenic and anti-inflammatory properties. In the current study, we have analyzed the relationship between adiponectin and insulin resistance in rhesus monkeys (Macaca mulatta), which spontaneously develop obesity and which subsequently frequently progress to overt type 2 diabetes. The plasma levels of adiponectin were decreased in obese and diabetic monkeys as in humans. Prospective longitudinal studies revealed that the plasma levels of adiponectin declined at an early phase of obesity and remained decreased after the development of type 2 diabetes. Hyperinsulinemic-euglycemic clamp studies revealed that the obese monkeys with lower plasma adiponectin showed significantly lower insulin-stimulated peripheral glucose uptake (M rate). The plasma levels of adiponectin were significantly correlated to M rate (r = 0.66, P < 0.001). Longitudinally, the plasma adiponectin decreased in parallel to the progression of insulin resistance. No clear association was found between the plasma levels of adiponectin and its mRNA levels in adipose tissue. These results suggest that reduction in circulating adiponectin may be related to the development of insulin resistance.