Chimerism and tolerance in rat recipients of intestinal allografts from ALS-treated donors with and without adjunct naïve-donor-strain bone-marrow cells

BACKGROUND: BN --> LEW small-intestine transplantation (SITx) given a 28-day course of tacrolimus results in partial tolerance and prolonged alloengraftment despite the development of indolent chronic rejection (CR). We determined whether the CR was associated with the quantity or quality of passenger leukocytes contained in the unmodified or antilymphocyte serum (ALS)-depleted BN intestine at the time of transplantation, and with the subsequent migration and persistence of these donor leukocytes in the LEW recipients (chimerism). METHODS: Four experimental cohorts were defined by differences of the BN allografts and by the infusion (or not) of na?ve donor (bone marrow cells [BMC]) on the day of the BN --> LEW SITx. All LEW recipients were treated with the same 28-day course of tacrolimus. The LEW animals received: (1) unaltered intestine; (2) intestine from ALS-treated donor; (3) intestine from ALS-treated donor plus BMC from naive BN donor on day 0; and (4) unaltered intestine and BMC from unmodified (na?ve) BN donor. RESULTS: Blood chimerism during the first 2 weeks after transplantation was lowest in the recipients of intestine from ALS-treated donors (groups 2 and 3), apparently because of the nearly complete elimination from the bowel of alphabetaTCR+ passenger leukocytes. After 2 weeks posttransplant to 5 months, greater than 2% of circulating donor cells were seen in animals given adjunct BMC from na?ve BN donors (groups 3 and 4); this was associated with the absence of CR in the intestinal allografts. With lower levels of chimerism, moderate CR including arteritis and fibrosis in the Peyer's patches and mesenteric lymph nodes was found in the intestinal grafts of all group 1 and group 2 animals. Nevertheless, the CR-prone recipients in groups 1 and 2 had equivalent weight gain for greater than or equal to 150 days as in the CR-free groups 3 and 4. Detailed tissue chimerism studies in groups 1 to 3 showed that most of the donor cells in the gut-associated lymphoid tissues were rapidly replaced, but that the residual donor constituency of up to 6% in the allografts of group 3 was nearly 10-fold greater at 150 days than in groups 1 and 2 and closely reflected the findings in blood. CONCLUSION: The development of CR in intestinal allografts to which the recipients are partially tolerant is associated with a decline with time of donor-leukocyte chimerism. Multilineage chimerism in the recipient, and a similar profile of donor cells in the allografts, is better achieved with infused donor BMC than with the normal intestinal passenger leukocytes of the intestine. The difference may be because of a higher number of precursor and pluripotent stem cells in BMC.     

Oral UFT and cyclophosphamide combination chemotherapy for metastatic breast cancer

BACKGROUND: Effective long-term chemotherapy yielding good quality of life is essential. The clinical benefits of oral UFT and cyclophosphamide (CPA) combination chemotherapy for metastatic breast cancer (MBC) were evaluated. PATIENTS AND METHODS: Twenty cases with MBC were enrolled. The mean age was 54 years. Five cases had loco-regional and others had distant metastasis. Nineteen cases had previous therapies. Daily treatment consisted of UFT (300 to 400 mg/body) and CPA (100 to 150 mg/body), both given orally. RESULTS: The treatment period ranged from 4 to 80 weeks. The response rate was 35%, while it was 65% in the "stable disease > 6 months" category. The mean time to the first sign of response was 7 weeks and the time to tumor progression was 37 weeks. The frequent adverse effects were leukocytopenia (55%) and gastrointestinal symptoms (35%). The incidence of adverse grade > or = 3 effects was 25%. CONCLUSION: Oral UFT and CPA combination chemotherapy may be suitable for MBC.     

Tumor initiating activity of Helicobacter pylori water extract on mouse skin carcinogenesis

Helicobacter pylori (H. pylori) infection has been associated with gastric carcinogenesis, but responsible and detail mechanisms are insufficient by the absence of adequate data. To obtain direct evidence regarding the carcinogenicity of H. pylori, we investigated the initiating and promoting activity of H. pylori water extract (HPE) in two-stage mouse skin carcinogenesis model. HPE treatment, as an initiation, significantly enhanced tumor formation compared with control group. Moreover, HPE treatment increased production of 8-hydroxydeoxyguanosine in epidermal cells and HPE-initiated/TPA-promoted papillomas demonstrated a point mutation of the Ha-ras gene. These results suggest an initiating activity of HPE on two-stage mouse skin carcinogenesis.     

Hyperthermia enhances tumor necrosis factor alpha-induced apoptosis of a human gastric cancer cell line

We have investigated the effects of hyperthermia on the apoptosis induced by tumor necrosis factor alpha (TNF-alpha). Confluent monolayers of human gastric cancer cell line MKN45 were either treated or untreated with hyperthermia for 1 h. The cells were subsequently stimulated with TNF-alpha. A 24-h incubation with TNF-alpha did not affect cell viabilities; however, pretreatment with hyperthermia significantly enhanced the level of apoptosis induced by TNF-alpha. Pretreating MKN45 cells with hyperthermia (42.0 degrees C) significantly inhibited the TNF-alpha-induced increase in the binding activity of NF-kappaB to DNA. This study suggests that hyperthermia can inhibit the TNF-alpha-induced NF-kappaB activation and that hyperthermia renders human gastric cancer cells susceptible to the TNF-alpha-induced apoptosis, possibly via inhibition of the NF-kappaB pathway.     

Expression of vascular endothelial growth factor C and D (VEGF-C and -D) is an important risk factor for lymphatic metastasis in undifferentiated early gastric carcinoma

BACKGROUND: Vascular endothelial growth factor C (VEGF-C) and D (VEGF-D) are considered to be potentially lymphangiogenic and can selectively induce hyperplasia of the lymphatic vasculature. In this study, we aimed to clarify the relation between expression of VEGF-C and -D and lymphatic metastasis in early gastric cancers. METHODS: Using the specific antibodies, we classified 105 cases which were treated as gastrectomy with standard lymphadenectomy at the First Department of Surgery, Tokyo University Hospital, between 1994 and 2001, into three groups (diffuse type, focal type and negative type) for VEGF-C and two groups (positive and negative) for VEGF-D. RESULTS: There was a significant correlation between the expression of VEGF-C and -D and lymphatic invasion but not with venous invasion. All of the 22 cases that were negative for VEGF-C and -D were histologically classified as adenocarcinoma of undifferentiated type and showed negative lymph node metastasis and also negative lymphatic invasion. VEGF-C was positive in all tumors of differentiated type, while its expression varied in tumors of undifferentiated type. The VEGF-D positive rate is much lower than that of VEGF-C. In undifferentiated tumors in particular, VEGF-D was positive only in 4/64 (6%) and three of these four had nodal metastasis. Therefore, in tumors of differentiated type, expression of VEGF-C and -D had no clinical relevance. In tumors of undifferentiated type, the negative expression of VEGF-C suggests lack of nodal metastasis, while the positive expression of VEGF-D suggests nodal metastasis. The lymph node metastasis was significantly related to the expression of VEGF-C and -D in adenocarcinomas of undifferentiated type but not in those of differentiated tumors. CONCLUSIONS: In early gastric cancers of histologically undifferentiated type with negative expression of VEGF-C and -D, limited surgery might be safely applied because the possibility of nodal metastasis is very low. These observations are based only on retrospective analysis of a small case series and further evaluation with a larger number of cases is necessary.     

Optimal dosing schedule in combination therapy with irinotecan and doxifluridine in a human colorectal cancer xenograft model

A combination therapy with CPT-11 and 5-FU/LV has been recently established as a first-line therapy for metastatic colorectal cancer. However, severe adverse effects have also been reported from this combination therapy, and a modality to reduce the adverse effects is desired. 5'-DFUR, a pro-drug of 5-FU, shows less myelotoxicity than 5-FU, and thus it may be a better partner to combine with CPT-11. However, since each drug has the possibility of inducing diarrhea, there is concern about their use in combination therapy. Therefore, in the present study, our aim was to establish an optimal schedule in murine models, which shows no increase in diarrhea but maintains potent antitumor activity. In non-tumor bearing mice, CPT-11 was given i.v. at 100 mg/kg/day q2d x 3, and 5'-DFUR was given p.o. at 172 mg/kg/day daily for 14 days. Each of these doses caused diarrhea in the single treatment. CPT-11 was administered simultaneously or sequentially with 5'-DFUR. With the simultaneously administered schedule, the diarrhea appeared stronger than that found in the CPT-11 single or in the 5'-DFUR single treatment groups. On the other hand, with the sequentially administered schedule the diarrhea was not much stronger than that found in the single agent treatment groups. When CPT-11 and 5'-DFUR administrations were separated by three-day intervals, the diarrhea was not augmented at all. In mice bearing human colorectal cancer COLO 205, the antitumor activity of CPT-11 in the combination with 5'-DFUR was additive in all of the examined schedules. The efficacy in the sequential schedule was the same as in the simultaneous schedule. These results suggest that a sequential administration schedule of CPT-11 and 5'-DFUR would be more tolerable than and equally efficacious to the simultaneous administration schedule. Clinical study of this sequential administration in combination therapy is warranted.     

Human wee1 kinase is directly transactivated by and increased in association with c-Fos/AP-1: rheumatoid synovial cells overexpressing these genes go into aberrant mitosis

Wee1 kinase downregulates the M-phase promoting factor, a complex of cdc2 and cyclin B kinase, that controls mitotic cell division. We isolated human wee1 kinase gene promoter and found that it contained one AP-1-binding motif in its promoter region (5'-CGAGTCA-3'; -823/-817), through which wee1 kinase gene was directly transactivated by c-Fos/AP-1. In rheumatoid synovial cells, wee1 kinase was increased in conjunction with the increase of c-Fos/AP-1 and the substrate of wee1, cdc2, was phosphorylated. The amount of wee1 and c-Fos and the phosphorylation of cdc2 were decreased after treatment of the cells with an inhibitor of AP-1, curcumin. A significant proportion of cultured synovial cells of the patients with rheumatoid arthritis, but not those of osteoarthritis, shifted to a tetraploid (4C) state upon long-term culture. Thus, human wee1 kinase gene is directly transactivated by and increased in association with c-Fos/AP-1, and rheumatoid synovial cells overexpressing these genes go into aberrant mitosis.     

Augmentation of the antitumor activity of capecitabine by a tumor selective dihydropyrimidine dehydrogenase inhibitor,RO0094889

Capecitabine is an orally available fluoropyrimidine and is finally converted to 5-FU selectively in tumor tissues. In our study, we examined whether the antitumor activity of capecitabine is directly affected by a modulation of dihydropyrimidine dehydrogenase (DPD). The modulations were carried out by the overexpression of DPD in tumor cells and by tumor selective DPD inhibition. The DPD-overexpressing cells were obtained by transfection of human DPD cDNA into HCT116 human colorectal cancer cells. The HCT116 cells bearing DPD cDNA expressed about 13 times higher DPD activities than the parental HCT116 cells, and they became significantly less susceptible to capecitabine than the parental cells when transplanted into nude mice. Administration of RO0094889 that is converted to a DPD inhibitor 5-vinyluracil selectively in tumor tissues restored the antitumor activity of capecitabine against the tumor of the HCT116 cells carrying DPD cDNA and various tumors expressing DPD. As compared to 5-ethynyluracil or 5-vinyluracil, which inhibited DPD not only in tumor tissues but also in other non-cancerous tissues, the effective dose range of RO0094889 in augmenting the efficacy of capecitabine was much broader. These results indicate that the antitumor activity of capecitabine is directly affected by DPD activities in tumor tissues and therefore, the combination of capecitabine and a tumor selective DPD inhibitor, RO0094889, will be beneficial to patients who have tumors with high levels of DPD.     

Glypican-3, overexpressed in hepatocellular carcinoma,modulates FGF2 and BMP-7 signaling

The Glypican (GPC) family is a prototypical member of the cell-surface heparan sulfate proteoglycans (HSPGs). The HSPGs have been demonstrated to interact with growth factors, act as coreceptors and modulate growth factor activity. Here we show that based on oligonucleotide array analysis, GPC3 was upregulated in hepatocellular carcinoma (HCC). By northern blot analysis, GPC3 mRNA was found to be upregulated in 29 of 52 cases of HCC (55.7%). By Western blot analysis carried out with a monoclonal anti-GPC3 antibody we generated, the GPC3 protein was found to be overexpressed in 6 hepatoma cell lines, HepG2, Hep3B, HT17, HuH6, HuH7 and PLC/PRF/5, as well as 22 tumors (42.3%). To investigate the role of overexpressed GPC3 in liver cancer, we analyzed its effects on cell growth of hepatoblastoma-derived cells. Overexpression of GPC3 modulated cell proliferation by inhibiting fibroblast growth factor 2 (FGF2) and bone morphogenetic protein 7 (BMP-7) activity. An interaction of GPC3 and FGF2 was revealed by co-immunoprecipitation, while GPC3 was found to inhibit BMP-7 signaling through the Smad pathway by reporter gene assay. The modulation of growth factors by GPC3 may help explain its role in liver carcinogenesis. In addition, the ability of HCC cells to express GPC3 at high levels may serve as a new tumor marker for HCC.