Host stromal bradykinin B2 receptor signaling facilitates tumor-associated angiogenesis and tumor growth

We evaluated the significance of the host kallikrein-kinin system in tumor angiogenesis and tumor growth using two rodent models genetically deficient in a kallikrein-kinin system. Inoculation of Walker 256 carcinoma cells into the s.c. tissues of the back of normal Brown Norway Kitasato rats (BN-Ki rats) resulted in the rapid development of solid tumors with marked angiogenesis. By contrast, in kininogen-deficient Brown Norway Katholiek rats (BN-Ka rats), which cannot generate intrinsic bradykinin (BK), the weights of the tumors and the extent of angiogenesis were significantly less than those in BN-Ki rats. Daily administration of B(2) receptor antagonists significantly reduced angiogenesis and tumor weights in BN-Ki rats to levels similar to those in BN-Ka rats but did not do so in BN-Ka rats. Angiogenesis and tumor growth were significantly suppressed in B(2) receptor knockout mice bearing sarcoma 180 compared with their wild-type counterparts. Immunoreactive vascular endothelial growth factor (VEGF) was localized in Walker tumor stroma more extensively in BN-Ki rats than in BN-Ka rats, although immunoreactive B(2) receptor also was detected in the stroma to the same extent in both types of rats. Cultured stromal fibroblasts isolated from BN-Ki rats and BN-Ka rats produced VEGF in response to BK (10(-8)-10(-6) m), and this stimulatory effect of BK was abolished with a B(2) receptor antagonist, Hoe140 (10(-5) m). These results suggest that BK generated from kininogens supplied from the host may facilitate tumor-associated angiogenesis and tumor growth by stimulating stromal B(2) signaling to up-regulate VEGF production mainly in fibroblasts.     

Nutritional status and cytokine-related protein breakdown in elderly patients with gastrointestinal malignancies

BACKGROUND: Age-related factors affecting cytokine-related whole-body protein breakdown and their relation to clinical outcomes in cancer patients were investigated. METHODS: For assessment of protein-calorie malnutrition and protein breakdown, the creatinine height index (CHI) and daily urinary excretion of 3-methylhistidine (3-MH) were measured in 70 patients with gastrointestinal malignancies. Perioperative cytokine profile was evaluated to assess its relation to perioperative protein catabolism. RESULTS: In elderly patients, daily 3-MH excretion during the stable preoperative period decreased with the increase of tumor interleukin (IL)-6 production, suggestive of the activation of a metabolic compensation mechanism. However, these patients showed significant increases in postoperative 3-MH excretion in accord with perioperative systemic IL-6 response, and this deterioration of the compensating mechanism seemed to be associated with poor clinical outcome. An increase in 3-MH excretion under surgical stress was positively correlated with postoperative consumption of IL-6 soluble receptor (sR) in elderly patients with nutritional depletion. CONCLUSIONS: In elderly cancer patients with protein-calorie malnutrition, metabolic compliance against intrinsic IL-6 may be compensated for in the preoperative stable period, but deteriorate from surgical insults. This mechanism might involve increased affinity of IL-6 with IL-6sR under surgical stress.     

Induction of anti-leukemic cytotoxic T lymphocytes by fusion of patient-derived dendritic cells with autologous myeloblasts

Presentation of AML antigens by dendritic cells (DC) could potentially induce a T cell-mediated anti-leukemic immune response. In the present study, we generated DC from adherent (AD-DC) and non-adherent (NAD-DC) myeloblasts obtained from bone marrows of AML patients. Both cell populations displayed morphological, phenotypic and functional properties of DC. The functions of NAD-DC were compared to AD-DC that had been fused with autologous AML blasts (FC/AML). The FC/AML induced greater T cell proliferation and CTL activity against autologous AML blasts (9/10 cases) as compared to NAD-DC. FC/AML may thus represent a promising strategy for DC-based immunotherapy of patients with AML.     

Plasminogen activator inhibitor-1 is a downstream mediator of the PGP9.5-related oncogenic pathway in esophageal squamous cell carcinoma

BACKGROUND & MATERIALS AND METHODS: Recently, it has been proved that PGP9.5 is an oncogene candidate for squamous cell carcinomas. To examine the PGP9.5-related oncogenic pathway, we tested for global patterns of gene expression in cancer cells following PGP9.5 gene introduction using an oligonucleotide microarray approach. RESULTS: Plasminogen activator inhibitor-1 (PAI-1) was identified as an overexpressed gene in a PGP9.5-expressed esophageal squamous cancer cell line. To confirm the data obtained, we performed Northern analysis using a PGP9.5 or a PAI-1 cDNA probe and found that PAI-1 mRNA was induced by PGP9.5 expression in NUEC1 cells. We further examined endogenous PGP9.5 and PAI-1 expression in 6 esophageal cancer cell lines. One cell line (NUEC2) with PGP9.5 expression exhibited PAI-1 expression, suggesting the possibility that PGP9.5 might induce PAI-1 directly or indirectly. CONCLUSION: These results suggested that PAI-1 might be a novel downstream mediator of PGP9.5 in esophageal squamous cell carcinomas.     

A phase I study of combination chemotherapy using TS-1 and pirarubicin (THP) for advanced gastric cancer

The safety of chemotherapy combining TS-1 and pirarubicin (THP) for treatment of recurrent or locally advanced gastric cancer was evaluated. THP was administered by intravenous drip infusion at a dose of 14 mg/m2 every other week. TS-1 was administered orally at a dose of 40 mg/m2 twice a day for 2 weeks followed by 2 weeks of rest (level 1), for 3 weeks followed by 2 weeks of rest (level 2), and for 4 weeks followed by 2 weeks of rest (level 3). Three patients were treated with the level 1 schedule. One patient with peritoneal dissemination received 22 courses of the treatment, and benefited from a long-term NC. However the remaining 2 cases were diagnosed as PD after 4 courses and were withdrawn from further treatment. Two patients in this group suffered from grade 2 adverse events according to the NCI-CTC. Only 1 patient who had liver metastasis was treated at level 2. Fourteen courses were administered, and a PR was achieved while grade 2 adverse events were observed. One of 3 patients who were treated with level 3 had grade 3 adverse events. Consequently, 3 more cases were added to this dose level, and no additional grade 3 adverse events were observed, while grade 2 adverse events were seen in 4 cases. Urinary urgency had completely disappeared in 1 patient with peritoneal recurrence. Myelosuppression, which was the main observed adverse event, was well controlled and of brief duration. The response, including alleviation of clinical symptoms, was confirmed in 3 of 5 chemo-naive patients.     

A case of pulmonary metastases from laryngeal cancer showing a complete response to chemotherapy with docetaxel

Docetaxel (TXT) is a new cytotoxic agent against head and neck, (H and N) cancer since the emergence of cisplatin. We herein describe the efficacy of TXT in treating distant metastases from H and N cancer. The patient was a 61-year-old man who had undergone laryngectomy and irradiation for laryngeal cancer (glottic type: T3N0M0). More than 2 years later after the first course of therapy, pulmonary metastases involved in the left lower area were revealed by lung CT. The divided TXT therapy (20 mg, 3 times, and 40 mg, 3 times) was carried out without any sequelae. This consecutive therapy resulted in complete disappearance of the metastases on follow-up CT. It is suggested that divided TXT therapy has potential as a new treatment modality for distant metastases of H and N cancer.     

Growth inhibition and induction of apoptosis in mesothelioma cells by selenium and dependence on selenoprotein SEP15 genotype

Malignant mesotheliomas (MMs) are aggressive tumors derived from mesothelial cells lining the lungs, pericardium and peritoneum, and are often associated with occupational asbestos exposure. Suppression subtractive hybridization was used to identify genes differentially expressed in MM cells compared to normal mesothelial cells. A gene, SEP15, encoding a 15-kDa selenium-containing protein was isolated using this approach and was subsequently shown to be downregulated in approximately 60% of MM cell lines and tumor specimens. A SEP15 polymorphic variant, 1125A, resides in the SECIS recognition element in the 3'-UTR and may influence the efficiency of Sec incorporation into the protein during translation. Since previous studies have implicated a potential role of the trace element selenium as a chemopreventive agent in animal models and in several types of human cancer, we investigated the effect of selenium on MM cells and its dependence on SEP15 genotype. Selenium was shown to inhibit cell growth and induce apoptosis in a dose-dependent manner in MM cells but had minimal effect on normal mesothelial cells. However, MM cells with downregulated SEP15 or the 1125A variant were somewhat less responsive to the growth inhibitory and apoptotic effects of selenium than MM cells expressing wild-type protein. RNAi-based knockdown studies demonstrated that SEP15 inhibition makes sensitive MM cells more resistant to selenium. These data imply that selenium may be useful as a chemopreventive agent in individuals at high risk of MM due to asbestos exposure, although those with the 1125A polymorphism may be less responsive to the protective benefits of dietary selenium supplementation.     

Regulation of caspase-6 and FLIP by the AMPK family member ARK5

Colorectal cancer cells are unique in that they escape Fas-mediated cell death in the presence of Fas ligand, and we recently reported that AMP-activated protein kinase-related kinase 5 (ARK5) suppresses cell death signaling mediated by cell death receptor in Akt-dependent manner. In the current study, therefore, we examined whether ARK5 is involved in the escape from Fas-mediated cell death of colorectal cancer cells. Among 10 cell lines, ARK5 mRNA expression was observed in LoVo, SW480, and SW1116 cell lines. Interestingly, SW480 and SW1116 cell lines, but not LoVo cell line, showed expressions of both Fas ligand (FasL) and Fas mRNAs. SW620 cell line also showed FasL mRNA; however, Fas and ARK5 mRNAs were not detected. Furthermore, well-coincided expression among ARK5, FasL, and Fas mRNAs was observed in tumor tissues from patients with colorectal cancer, suggesting the suppression of FasL/Fas system-induced cell death by ARK5 in colorectal cancer cell lines. Intensive cell death, which was dependent on the FasL/Fas system was encountered when ARK5 antisense RNA (ARK5/AS) was introduced into SW480 cells. FLIP was expressed in only ARK5 mRNA-expressing cell lines, and ARK5/AS induced FLIP cleavage in a caspase-6-dependent manner. Amino-acid sequence analysis of caspase-6 revealed two putative sites of phosphorylation by ARK5 at Ser80 and Ser257. Although active caspase-6 overexpression induced cell death in SW480 and DLD-1 cell lines, SW480 cells, but not DLD-1 cells, exhibited strong resistance to procaspase-6 overexpression. Moreover, mutant caspase-6, in which the Ser257 was substituted by Ala (caspase-6/SA), induced cell death and FLIP degradation, even in SW480 cells. Active ARK5 was found to phosphorylate wild-type caspase-6 in vitro, but not caspase-6/SA, and the prevented activation of caspase-6 was promoted due to its phosphorylation by active ARK5 in vitro. On the basis of the results of this study, we propose that ARK5 negatively regulates procaspase-6 by phosphorylation at Ser257, leading to resistance to the FasL/Fas system.     

Bone marrow necrosis in a patient with acute promyelocytic leukemia during re-induction therapy with arsenic trioxide

Arsenic trioxide (As2O3) therapy at a daily dose of 0.15 mg/kg was given to a 60-yr-old Japanese male with refractory acute promyelocytic leukemia. White blood cell (WBC) of 6.6 x 10(3)/microl increased to 134 x 10(3)/microl following the administration of As2O3. Daily hydroxyurea (HU), and 6-mercaptopurine (6-MP) were added on days 7 and 19, respectively. Both HU and 6-MP were discontinued on day 28, when WBC declined to 54.0 x 10(3)/microl. He developed unexplained fever and profound cytopenia requiring multiple blood products transfusions. Bone marrow examination on day 42 revealed massive necrosis. Pharmacokinetics confirmed a mean maximum plasma arsenic concentration (Cpmax) and a half-life time (t1/2) of 6.9 microm and 3.2 h, respectively, in the therapeutic range. This is the first case of bone marrow necrosis after standard-dose As2O3 therapy.     

Effectiveness of propagermanium treatment in multiple myeloma patients

Interferon (IFN) is one of several drugs effective in treating multiple myeloma (MM), and propagermanium is an IFN inducer. We report on 10 MM patients who were treated with propagermanium at doses from 10 to 40 mg. Two patients achieved complete remission (CR), two patients achieved partial remission (PR), and the condition of four patients was stable (stable disease, SD). After discontinuation of propagermanium, the status of MM progressed in two patients who were in SD and in two patients who had achieved PR. The administration of propagermanium was restarted in one patient resulting in a decrease in her paraprotein.