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Cholecystokinin (CCK) inhibits pancreatic cancer but not hepatic tumor induction by N-nitrosobis (2-oxopropyl) amine (BOP) in hamsters when administered with or shortly before BOP. In this study, we evaluated the capability of sulfated CCK-8 to inhibit DNA alkylation in the hamster pancreas. We examined the pattern of O6-methylguanine (G6-Me) and N7-methylguanine (G7-Me) in pancreatic ductal, acinar and liver tissues from Syrian hamsters treated with a single dose of BOP (20 mg/kg s.c.) and with five s.c. injections of CCK-8 (200 pM/kg, 30 min apart). The first CCK injection was given either 90 min before, or together, or 3 h after POP administration. The amount of G6-Me in liver DNA did not differ significantly. We observed a decrease of G7-Me in the liver of the group treated with CCK together with POP as compared to POP alone (P less than 0.005). Lower amounts of G6-Me were found in ductal preparations (P less than 0.01) of the animals treated with CCK before POP as compared to POP alone. CCK also modified the pattern of alkylation in the acinar tissue, but without a clear relationship with the timing of administration. The results suggest that the inhibitory effect of CCK-8 on pancreatic carcinogenicity of BOP could be related to its capability to modify DNA alkylation by yet unknown mechanisms.  相似文献   
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Annexins are a family of calcium- and phospholipid-binding proteins related by amino acid sequence homology. Annexins I and II are substrates for protein tyrosine kinases. Recent investigations have revealed a possible involvement of annexins I and II in mitogenic signal transduction and cell proliferation. To investigate further the involvement of annexins in cell proliferation, we measured the levels of annexins I and II and the enzyme 3-phosphoglycerate kinase (PGK) (annexin II and PGK are components of the primer recognition protein complex) in normal Syrian hamster pancreas, three hamster pancreatic ductal carcinoma cell lines, and allografts of the three cell lines into hamster pancreas. All three carcinoma cell lines had 5-8-fold higher levels of annexin II compared to normal pancreas. An inverse relationship was seen between level of annexin II and the doubling time of the cell culture. In intrapancreatic allografts, annexin II levels were 3-6-fold higher than in normal pancreas. Annexin I levels were 2-3-fold higher in the allografts. Significant increases (5-6-fold) in specific activity of PGK were seen in all allografts examined. However, the level of PGK, as measured by immunoblotting, was not significantly altered. Immunohistochemical staining revealed heterogeneity in the reactivity of the antiannexin and anti-PGK antibodies with tumor cells. Strikingly, the reactivity and staining intensity were greater in the proliferating regions of the primary tumors and in the metastatic foci. Mitotic cells were either unstained or very weakly stained. We conclude from these findings that annexin II and PGK, as primer recognition proteins, may have a role in cell proliferation.  相似文献   
4.
Nociceptin/orphanin FQ (N/OFQ), the endogenous ligand of the opioid receptor-like receptor or nociceptin receptor (NOP), has been shown to induce feeding, locomotion, anti-stress and anxiolytic effects in rodents after central nervous system injection. In this study, the effect of intracerebroventricular (icv) injection of N/OFQ on feeding and locomotion behavior was evaluated in male broiler-type chickens. The icv injection of N/OFQ caused a moderate but significant increase in feed intake similar to the classical opioid peptides in rats. It also increased feed pecking frequency and feeding time 1 h after injection. Stepping, wing flapping and preening were not affected by N/OFQ. These results suggest that N/OFQ can act within the central nervous system of chickens to increase feed intake.  相似文献   
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Enhanced pancreatic and skin tumorigenesis in cabbage-fed hamsters and mice   总被引:1,自引:0,他引:1  
Studies were conduded to evaluate the ability of dietary driedcabbage supplements to inhibit pancreatic carcinogenesis inhamsters and skin tumorigenesis in mice. Pancreatic cancer wasinduced by treatment with 40 mg/kg body wt N-nitrosobis-(2oxopropyl)amine(BOP). Cabbage was fed from before carcinogen treatment in lowfat diet and, beginning 1 week after BOP treatment, cabbagewas given in low fat and high fat diets in comparison with therespective non-cabbage containing diets. Dried cabbage was incorporatedat 9 and 11% levels into the low and high fat diets. Feedingcabbage in the high fat diet elevated the yield of BOP-inducedpancreatic ductular cardnoma (1.6 carcinomas/effedive animal)in comparison with that observed in hamsters fed cabbage ina low fat diet or in those given a high fat diet without cabbage, 0.6–0.8 carcinomaa/effedive animal (P 0.05). Furthermore,the incidence of BOP-induced gall bladder adenocadnomm was elevatedin cabbage-fed hamsters irrespedve of dietary fat intake. Effetsof dietary fat and cabbage on food consumption, body weight,and serum T3 and T4 values are described. Skin tumorigenesiswas induced in SENCAR mice by 10 nmd 7,12 dlmethylbenz[a]anthracene(DMBA) and promoted beginning 1 week later with twice weeklyapplications of 2 µg 12-O-tetradecanoyl-13-phorbol acetate(TPA). Dried cabbage was incorporated into AIN semi-purifieddiets from before DMBA treatment and throughout TPA treatment.Skin papilloma yield was elevated in DMBA-initiated TPA-promotedmice that were fed diets containing 10% cabbage. Mice fed cabbagedeveloped an average of 8.45 papillomas per mouse following22 weeks of promotion while mice given control diet developed7.25 papillomas per mouse (P < 0.001). Cabbage feeding didnot influence survival, food consumption or body weight of themice. These results suggest the need for further research onthe use of cabbage as a chemopreventive measure.  相似文献   
7.
Renal impairment (RI) is common in patients with multiple myeloma (MM) and new therapies that can improve renal function are needed. The phase III IKEMA study (clinicaltrials gov. Identifier: NCT03275285) investigated isatuximab (Isa) with carfilzomib and dexamethasone (Kd) versus Kd in relapsed MM. This subgroup analysis examined results from patients with RI, defined as estimated glomerular filtration rate <60 mL/min/1.73 m². Addition of Isa prolonged progression-free survival (PFS) in patients with RI (hazard ratio: 0.27; 95% confidence interval [CI]: 0.11–0.66; median PFS not reached for Isa-Kd versus 13.4 months for Kd [20.8-month follow-up]). Complete renal responses occurred more frequently with Isa-Kd (52.0%) versus Kd (30.8%) and were durable in 32.0% versus 7.7% of patients, respectively. Treatment exposure was longer with Isa-Kd, with median number of started cycles and median duration of exposure of 20 versus 9 cycles and 81.0 versus 35.7 weeks for Isa-Kd versus Kd, respectively. Among patients with RI, the incidence of patients with grade ≥3 treatment-emergent adverse events was similar between the two arms (79.1% in Isa-Kd vs. 77.8% in Kd). In summary, the addition of Isa to Kd improved clinical outcomes with a manageable safety profile in patients with RI, consistent with the benefit observed in the overall IKEMA study population.  相似文献   
8.
Yalniz M  Pour PM 《Pancreas》2005,31(2):108-118
A vast number of studies indicate the presence of stem/progenitor cells virtually in all tissues in adult organs, particularly in bone marrow. Recent studies, however, cast doubt about the existence of true stem cells in adult tissue. The complex integrity of several cells with distinct morphologic and functional properties in the mature pancreas confers an appropriate status for stem cell research. Several different types of cells residing in the islets or in the ductal epithelium have been proposed as adult pancreatic stem cells or progenitor cells. However, these reports do not provide conceivable proof for the presence of true pancreatic stem cells. On the other hand, there is considerable evidence indicating transdifferentiation of all adult pancreatic cells into each other, and under proper conditions, to nonpancreatic cells including oncocytes and hepatocytes. Observations pertaining to the putative pancreatic stem cells, transdifferentiation ability of the differentiated mature pancreatic cells in the normal and diseased pancreas will be discussed, and our own findings supporting the transdifferentiation pathway are presented in this article.  相似文献   
9.
Physiologic angiogenesis takes place during tissue growth and repair, during the female reproductive cycle, and during fetal development. Angiogenesis is also required for tumor growth and metastasis and, therefore, represents an exciting target for cancer treatment. Angiogenesis is a complex process that is tightly regulated by pro- and antiangiogenic growth factors. Pathologic angiogenesis is characterized by either excessive (eg. cancer) or inadequate (eg. coronary artery disease) neovascularization. Avascular tumors are severely restricted in their growth potential because of the lack of a blood supply. For tumors to develop in size and metastatic potential they must make an "angiogenic switch" through perturbing the local balance of proangiogenic and antiangiogenic factors. Frequently, tumors overexpress proangiogenic factors, such as vascular endothelial growth factor, allowing them to make this angiogenic switch. Two strategies used in the development of antiangiogenic agents involve the inhibition of proangiogenic factors (eg. anti-vascular endothelial growth factor monoclonal antibodies) as well as therapy with endogenous inhibitors of angiogenesis. Emerging antiangiogenic agents currently in clinical studies are discussed in this review.  相似文献   
10.
Adult Langerhans cell histiocytosis (LCH) usually follows a favorable course. Very rarely, however, multi-system (multi-organ) LCH difficult to manage either with traditional first line treatment (vinblastine, mercaptopurine, prednisone or etoposide) or 2-chlorodeoxyadenosine occurs. In these patients, other treatment modalities have to be used. We describe a patient with LCH manifesting with generalized lymphadenopathy and infiltrating the pulmonary parenchyma and skin. The disease activity was always associated with B-symptoms (weight loss, subfebrile states, night sweats). Histological investigations repeatedly showed higher proliferation activity than that usual in adult patients with LCH. Expression of Ki-67 proliferation marker was up to 30% and there were 8-10 cells in mitosis in the microscope viewing field. Therefore, therapy started with the application of stimulation regimen (cyclophosphamide 2 g/m2 on day 1 and etoposide 200 mg/m2 on days 1-3) followed by collection of peripheral blood stem cells. Then, treatment with 2-chlorodeoxyadenosine, the first 3 cycles as monotherapy of 5 mg/m2 SC on days 1-5 in 28-day cycles, the next 3 cycles in combination with cyclophosphamide 150 mg/m2 on days 1-5 and methylprednisolone 250 mg on days 1-5, was used. However, the disease relapsed 2 months after completion of the therapy. This early relapse was treated with 4 cycles of CHOEP chemotherapy (cyclophosphamide, doxorubicin, vincristine, etoposide, prednisone). Following the 4th cycle of CHOEP, high-dose BEAM chemotherapy (carmustine, etoposide, cytarabine, melphalan) with autologous stem cell transplantation were administered. According to the follow-up PET-CT examination, this treatment resulted in complete disease remission. However, the disease relapsed again in the lymph nodes, lungs, skin and bones 5 months after the high-dose chemotherapy. The progression was documented on PET-CT scanning. Lenalidomide 25 mg daily for 21 days in 28-day cycles with dexamethasone 20 mg once a week were administered as the 4th line treatment. After the 4th cycle of lenalidomide, PET-CT was performed, where the CT component suggested a significant reduction (more than 50%) in the size of the lymph nodes and the PET component showed substantial reduction in fluorodeoxyglucose accumulation in the affected lymph nodes as well as in the bone lesions. HRCT showed disappearance of pulmonary nodules. During the treatment, CRP levels declined and hemoglobin rose from 110 to 141 g/l, i.e. partial remission was achieved after 4 cycles. Etoposide (100 mg IV) was added to lenalidomide and dexamethasone on days 22, 23 and 24 of the above mentioned 28-day cycle. The added etoposide further intensified treatment response. In all, 11 cycles of this chemotherapy were given, resulting in complete remission confirmed by follow-up PET-CT. The achieved remission was consolidated using allogeneic bone marrow transplantation after FLAMSA reduced intensity conditioning without amsacrine. Four months after allogeneic transplantation, the patient has been relapse free. Herein we presented treatment response of highly aggressive LCH to lenalidomide. The used four cycles led to partial remission only and with the combination of lenalidomide, dexamethasone and etoposide the treatment response was further intensified to complete remission.  相似文献   
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