Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0598934 (tumor growth)
 58,965 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Nude mice bearing xenografts of MIA PaCa-2 human pancreatic cancer cell line were treated for 4 weeks with AN-51, a somatostatin octapeptide analog D-Phe-Cys-Tyr-D-Trp-Lys-Val-Cys-Thr-NH2 (RC-121) containing methotrexate attached to the alpha-amino group of D-Phe in position 1. Control groups of mice received saline, RC-121 or methotrexate. Drugs were given in equimolar doses by daily s.c. injections. After 7 days of treatment with 25 micrograms/day of AN-51, tumor growth was completely inhibited although the treatment had to be suspended because of toxic side effects, especially on the gastrointestinal tract, accompanied by major weight loss of the animals. Mice were allowed to recover for 1 week and treatment was continued with 12.5 micrograms/day AN-51. After 2 weeks of additional therapy, tumor volume, percentage change in tumor volume, and tumor weights were significantly decreased, compared with controls, only in the group treated with AN-51. Methotrexate and RC-121 also inhibited tumor growth, but their effects were not statistically significant. AN-51 retained its hormonal activity and decreased serum growth hormone levels in mice. Binding affinity of AN-51 for somatostatin receptors on MIA PaCa-2 cells was found to be 2.5-times lower than that of parent compound RC-121. This is the first report on inhibition of human pancreatic cancer growth in vivo by somatostatin analogs carrying cytotoxic radicals.
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PMID:Cytotoxic analog of somatostatin containing methotrexate inhibits growth of MIA PaCa-2 human pancreatic cancer xenografts in nude mice. 131 46

Pancreatic cancer is the fifth most common cause of death due to cancer. Except for an association with cigarette smoking, its etiology is poorly understood. Because of the dearth of epidemiological clues as to causation, studies with experimental animal models assume greater importance. Rodent models of pancreatic cancer indicate that while dietary fat per se does not cause pancreatic cancer, it does enhance or promote tumor development. Subsequent to treatment with a pancreatic carcinogen, high intakes of dietary unsaturated fats of the n-6 series, but not saturated fats, enhance or promote tumor development. A requisite level of linoleic acid is needed for this promotion. Fats of the n-3 series (e.g., certain fish oils) are inhibitory to tumor growth. Promotion by dietary fats appears only partly related to the high caloric content of fat. Mechanistically, certain dietary unsaturated fats appear to selectively enhance the growth rate of carcinogen-induced, pre-cancerous lesions. Irrespective of precise understanding of mechanisms of promotion, it appears possible to intervene in the process of cancer development and reduce the burden of cancer. Experimentally, this may be accomplished by decreasing total fat intake, decreasing caloric intake, increasing exercise or increasing the intake of n-3 fatty acids.
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PMID:Dietary fat and the development of pancreatic cancer. 143 99

Many reports have emphasized the role of gastrin as a growth factor for normal gastrointestinal mucosa and gastrointestinal cancers. Recent studies have pointed out that this peptide acts also as a growth factor for the pancreatic cancer cell line AR42J. This effect is mediated by gastrin [cholecystokinin (CCK)-B] receptors. In the present study, we investigated gastrin (CCK-B) receptor expression in the azaserine-induced rat pancreatic carcinoma DSL-6, comparing it to normal rat pancreas, and we also characterized CCK receptor subtypes in this tumor. The results showed that there is extensive gastrin binding to the DSL-6 pancreatic carcinoma. No evidence of specific gastrin binding to normal pancreas was found. Analysis of the ability of gastrin-17-I to inhibit 125I-gastrin-I binding demonstrated that gastrin bound to a single class of receptors with a Kd of 0.21 +/- 0.04 nM and a binding capacity of 184 +/- 29 fmol/mg protein. 125I-Gastrin-I binding was inhibited by the specific CCK-B receptor antagonist L365,260 approximately 40 times more effectively than by the specific CCK-A receptor antagonist L364,718. Analysis of the ability of cholecystokinin octapeptide (CCK-8) to inhibit 125I-Bolton-Hunter-CCK-8 binding revealed two CCK binding sites, i.e., a high affinity site and a low affinity site. The observed binding affinities of CCK-8 were then introduced into the computer analysis of the dose-inhibition curve of the ability of gastrin-17-I to inhibit binding of 125I-Bolton-Hunter-CCK-8, which was significantly better fit by a three-site model than by a two-site model. The three sites meet the criteria for CCK-B, high affinity CCK-A, and low affinity CCK-A receptors. The binding capacity of CCK-B receptors constitutes 34% of the total high affinity CCK binding sites. This study demonstrated that DSL-6 pancreatic carcinoma expresses three subtypes of CCK receptors. Gastrin (CCK-B) receptors, which were not detected in normal rat pancreas, constitute about one third of the total high affinity CCK receptors. We suggest that novel expression of gastrin (CCK-B) receptors may be generated by gene mutation or amplification during carcinogenesis and may play an important role in promoting tumor growth.
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PMID:Novel expression of gastrin (cholecystokinin-B) receptors in azaserine-induced rat pancreatic carcinoma: receptor determination and characterization. 145 79

Specific and nonspecific stimulation of the host immune system to reject cancer is an attractive concept that is just beginning to mature. Results with crude extracts and nonspecific immune stimulation have been variable. However, the recent observations of improved survival after administration of levamisole plus 5-fluorouracil in the adjuvant setting have made an impact on the treatment of colorectal cancer. Animal studies consistently show that immune therapies are most effective for disease that is not advanced. Thus, the small benefit seen with levamisole, a low toxicity immunomodulator, suggests that much more impressive results can be anticipated with more potent and specific agents. Postsurgical autologous tumor cell vaccine has been effective in some prospective randomized trials; in others, no benefit was found. The identification and purification of allogeneic tumor-associated antigens has lead to enhanced antigen-specific host cell-mediated immunity; this may result in more consistent antitumor effects. The current development of chemically defined immune adjuvants of low toxicity allows tumor-specific immune stimulation to be tested in high-risk apparently healthy patients after resection of colorectal cancer (Stages II and III). The influx of information regarding immune cell populations, cell-surface markers, and cytokines has fostered extensive exploration of lymphocyte stimulation, in vitro cell growth and expansion, and in vivo evaluation in patients with advanced cancer. Modest tumor response rates have been documented with adoptive transfer of lymphokine-activated killer cells and interleukin-2. Improved results are anticipated with the more potent tumor-infiltrating lymphocytes and specific in vitro sensitization of draining lymph node cells to autologous and allogeneic tumor antigens. Murine monoclonal antibodies specific for cell-surface markers, such as carcinoembryonic antigen, have been tested for their value in the diagnosis and therapy of colorectal cancer. A small response rate has been seen with single and multiple injections of C017-1A, a monoclonal antibody specific for colonic and pancreatic cancer. The development of antiidiotypic antibodies in these patients may have been important in those that responded to this type of therapy. However, laboratory evidence suggests that monoclonal antibody conjugated to a cytotoxic agent (i.e., radionuclide, drug, or toxin) should be much more effective. Radioimmunotherapy trials in the nude mouse model bearing human colon cancer xenografts showed good tumor incorporation of the radionuclide (yttrium 90 or iodine 131), inhibition of tumor growth, and long-term survival.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Immunotherapy of colorectal cancer. 151 94

Cholecystokinin (CCK) exerts an influential effect on the growth of normal pancreas. It is postulated that carcinoma arising from the pancreas may retain some normal pancreatic properties as far as hormone dependency is concerned. In an effort to examine the effect of CCK on the growth of pancreatic cancer, we evaluated the effect of CCK receptor antagonist on the growth of a transplantable adenocarcinoma of the pancreas. For this study we utilized three groups of hamsters with adenocarcinoma of the pancreas transplanted subcutaneously on the right flank. Group I (n = 15) served as control. Group II (n = 15) received CCK receptor antagonist (L-364,718), 0.1 mg/100 g body wt subcutaneously BID. Group III received CCK receptor antagonist in the same dose but treatment was started after tumors became palpable. All animals were examined daily. Latency for tumor growth, tumor size, and body weight were recorded. Animals were sacrificed after 3 weeks and final tumor volume and weight were measured. CCK receptor antagonist (L-364,718) significantly reduced pancreatic carcinoma growth when given immediately after transplantation and also in animals with established tumor. However, this inhibitory effect of L-364,718 was only partial and effective only for a brief time. This finding suggests CCK may have only a minimal influence on the biologic behavior of exocrine pancreatic cancer.
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PMID:Effect of CCK receptor antagonist on growth of pancreatic adenocarcinoma. 152 48

Pancreatic cancer is one of the most intractable and least understood of all human cancers. Pancreatic cancers is the fourth-leading cause of cancer-related mortality in the United States with less than 2% of the patients surviving for 5 yr. In an effort to help develop more effective treatment modalities for pancreatic cancer and improve detection, we report an animal model for individual human pancreatic-cancer patients. The model involves orthotopic transplantation of histologically intact pancreatic-cancer specimens to the nude-mouse pancreas, which can result in models that resemble the clinical picture including (i) extensive local tumor growth, (ii) extension of the locally growing human pancreatic cancer to the nude-mouse stomach and duodenum, (iii) metastases of the human pancreatic tumor to the nude-mouse liver and regional lymph nodes, and (iv) distant metastases of the human pancreatic tumor to the nude-mouse adrenal gland, diaphragm, and mediastinal lymph nodes. In a series of five patient cases, a 100% take rate has been demonstrated, and of 17 mice transplanted, 15 supported tumor growth. Immunohistochemical analysis of the antigenic phenotype of the transplanted human pancreatic tumors showed a similar pattern of expression of two different human tumor-associated antigens, such as tumor-associated glycoprotein 72 and carcinoembryonic antigen in the transplanted tumors when compared with the original surgical biopsy, suggesting similarity between the two. This model should, therefore, prove valuable for treatment evaluation of individual cancer patients, as well as for evaluation of experimental treatment modalities for this disease.
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PMID:A metastatic nude-mouse model of human pancreatic cancer constructed orthotopically with histologically intact patient specimens. 160 75

The prognostic influence on the DNA content was investigated in 189 patients (esophagus carcinoma n = 45, gastric cancer n = 103, pancreatic cancer n = 41) who underwent a curative resection. In a multivariate analysis the DNA content had a strong as well as an independent influence on the prognosis in esophagus cancer and in pancreatic carcinoma. In gastric cancer, the DNA content had no influence on the prognosis. These results show that the DNA content of the tumor cells, as a measurement of the numerous chromosomal aberrations, well reflects the aggressiveness of the tumor growth in esophagus- and pancreatic cancer. In these tumors it represents the decisive criteria for the prognostic judgement.
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PMID:[Image analysis of DNA cytometry in tumors of the upper gastrointestinal tract]. 163 18

The effects of insulin and somatostatin on the growth and the colony formation of two human pancreatic cancer cell lines, BxPC-3 and SOJ-6, were studied. The BxPC-3 cell line (American Type Culture Collection no. CRL 1687) was derived from a moderately differentiated pancreatic adenocarcinoma. The SOJ-6 cell line is a subclone of SOJ that was initiated from ascites of a well-differentiated pancreatic adenocarcinoma. Both cell lines express fetoacinar pancreatic antigen, an antigen that might be associated with early transformation stages. However, these lines have different proliferation and tumoral powers. SOJ-6 cells showed an almost twofold higher division rate over BxPC-3 cells when cultured in RPMI-1640 medium containing 10% fetal bovine serum. The tumorigenic degree of SOJ-6 cells, as assessed by tumor growth in nude mice, was about three times greater than that of BxPC-3. The in vitro growth of BxPC-3 cells was significantly promoted by insulin, and was slightly inhibited by somatostatin, whereas the growth of SOJ-6 cells was not influenced by these hormones. Using a clonogenic assay in soft agar, the average ratio of colony numbers formed by SOJ-6 and BxPC-3 was about 10/1, indicating a good correlation between the colony formation and tumorigenic degree in vivo. In this test, the number of colonies formed by BxPC-3 cells was increased about twofold in insulin-supplemented medium. On the other hand, somatostatin inhibited the colony formation by a factor of four to six. However, no hormonal modulation of the colony formation of SOJ-6 cells was observed. Our data show that pancreatic cancer cell lines respond differently to pancreatic hormones, and suggest that this may be correlated to a tumour stage or a tumour type.
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PMID:Effects of insulin and somatostatin on the growth and the colony formation of two human pancreatic cancer cell lines. 167 59

Antitumor effect of HO-221, a derivative of benzoylphenylurea, has been previously studied against seven human cancer xenografts in nude mice established and maintained in our laboratory. In this study, the effect of combination chemotherapy was examined with six of the above seven human cancer cell lines. These consisted of four gastric cancers (H-55, H-111, H-81 and H-154), one breast cancer (H-31) and one pancreatic cancer (H-48). HO-221 was used in combination with one of the following widely used anticancer drugs; mitomycin (MMC), adriamycin (ADM), CDDP, VP-16 and 5-fluorouracil (5-FU). When the tumor growth inhibition rate (IR) by combination of two drugs (at 1/2 MTD for each drug) exceeded both of IR obtained separately with single drug at 1/2 MTD, the combination regimen was rated as showing an additive effect. When IR by combination of two drugs at the same dose level exceeded both of IR obtained separately by MTD of each single drug, the regimen was rated as showing a synergistic effect. Histological changes and side-effects were also taken into consideration for the evaluation of the drug. Combination of HO-221 and MMC produced an additive effect against H-55 and H-111, a synergistic effect against H-81. In the treatment of H-31 which was highly susceptible to these drugs, a remarkable effect was shown in both IR and cellular changes even by combination using 1/2 MTD and 1/4 MTD doses. Combination with ADM at 1/2 MTD for both produced an additive effect against H-111 and H-48. Combination at MTD produced a marked antitumor effect against H-111 and a strikingly remarkable combination effect was confirmed. Combination with CDDP produced an additive effect against H-81 and a synergistic effect against H-154. Moreover, the weight loss by this combination regimen was far less than that by single administration of CDDP at MTD. An additive effect was demonstrated by combination with VP-16. Combination with 5-FU produced minimal combination effect. HO-221 was thus found to have a high antitumor effect by combination with various anticancer agents that are at present widely used clinically. HO-221 is expected to be a promising anticancer drug in its clinical application.
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PMID:[Combination chemotherapy of HO-221, a derivative of benzoylphenylurea with various anticancer agents against human cancer xenografts in nude mice]. 192 47

Pancreatic cancer is one of the neoplasms resistant to chemotherapy. In the present study human pancreatic cancer xenografts (3 adenocarcinomas and 1 cystoadenocarcinoma) were subcutaneously transplanted in nude mice and after the tumors grew to 100-300 mm3, the mice were intraperitoneally administered with mitomycin C (MMC), adriamycin (ADR), 5-fluorouracil (5-FU), carboquone (CQ), cisplatinum (CDDP), nimustine chloride (ACNU) or DWA2114R at 1/3 LD50 on days 0.4, and 8. The tumor sizes on day 12 were compared with those on day 0. MMC and CQ significantly inhibited the tumor growth of 3 lines, and ACNU, CDDP and ADR inhibited the growth of 1 line. Further, 5-FU, futrafur, carmofur, UFT and L-phenylalanine mustard (L-PAM) were orally administered to mice into which 1 adenocarcinoma line had been transplanted. While none of fluoropyrimidines inhibited tumor growth, L-PAM at 4 mg/kg significantly inhibited growth, although it was accompanied by severe body weight loss. In the present study several agents significantly inhibited tumor growth, but none of them could induce the regression of the tumor when used singly. These results suggest that CQ, ACNU, CDDP and L-PAM may be applied to the chemotherapy of pancreatic cancer. However, the effect of a single agent is restricted and the development of new combination treatments is urgently required.
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PMID:In vivo inhibitory effect of anticancer agents on human pancreatic cancer xenografts transplanted in nude mice. 206 19


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