Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0019204 (hepatocellular carcinoma)
 71,386 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The murine monoclonal antibody (MAb), designated DF3, reacts with a 300,000-mol wt mammary epithelial antigen. A sequential double-determinant radioimmunoassay (RIA) has been developed to monitor circulating DF3 antigen. Using this assay, we have demonstrated that 33 of 36 normal women had plasma RIA antigen levels less than 150 U/ml. In contrast, 33 of 43 patients (76%) with metastatic breast cancer had RIA DF3 antigen levels greater than or equal to 150 U/ml. The difference between these two groups was statistically significant (P less than 0.001). Similar results have been obtained with a double-determinant enzyme-linked immunoassay (EIA). Only 6 of 111 age-matched normal subjects had EIA DF3 antigens levels greater than or equal to 30 U/ml, while 42 of 58 patients (72%) with breast cancer had levels equal to or above this value. Thus, similar patterns of specificity are obtained with the EIA or RIA. The elevation of circulating DF3 antigen levels in breast cancer patients has been confirmed by transfer blot assays. MAb DF3 reactivity occurred predominantly with circulating antigens of three different molecular weights ranging from 300,000 to approximately 400,000 mol wt. We also demonstrate that patients with both primary and metastatic breast cancer who were free of detectable disease at the time of sampling have DF3 antigen levels that are similar to those obtained from normal subjects. While patients with hepatoma (27%) and ovarian carcinoma (47%) also had elevated circulating DF3 antigen levels, the results suggest that DF3 antigen levels may be useful in distinguishing breast cancer patients from those with esophageal, gastric, colorectal, pancreatic, and lung carcinomas. Furthermore, the results of the RIA, EIA, and transblot analyses demonstrate that the measurement of circulating DF3 antigen levels provides a new and potentially useful marker to follow the clinical course of patients with metastatic breast cancer.
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PMID:Use of a murine monoclonal antibody for detection of circulating plasma DF3 antigen levels in breast cancer patients. 388 57

The antitumor effect of human fibroblast interferon (HuIFN-beta) was examined using a nude mouse-human tumor xenograft group. Eight subcutaneously transplanted tumors--one line each of ovarian carcinoma, laryngeal carcinoma, carcinoma of the nasopharynx and hepatoma, and two lines each of lung carcinoma and melanoma--were used. HuIFN-beta at 1 X 10(5) IU/mouse was injected subcutaneously around the tumor or into the tumor itself. In the former case, statistically significant growth-suppressive effects were observed in one lung carcinoma (PC-12) and both melanomas (AM-1 and SK-14), but no effect was seen on the other five tumors. Further studies were made to ascertain the effects of intratumoral injections. Increased growth inhibition was observed in both melanomas (AM-1 and SK-14), but not in lung cancer (PC-12). Complete regression was seen in 3 of 8 mice carrying SK-14. The sensitivity of tumors to HuIFN-beta was correlated to the inhibitory effect of HuIFN-beta on cell division detected by histological observation.
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PMID:Effects of human fibroblast interferon on human tumors transplanted into nude mice: sensitivity of human tumors to interferon. 716 May 83

Subcutaneous transplants of hepatoma and ovarian carcinoma strains grew slower in a group of newborn mice preirradiated with a sublethal dose of 750 R as compared with groups of intact newborn and adult animals. Sublethal preirradiation of adult mice in a dose of 600 R produced no steady effect on the subsequent growth of the tumors.
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PMID:[Effect of sublethal pretransplantation irradiation on the growth of syngeneic tumors in newborn mice]. 722 57

1. A systematic study is reported on the control of 1-phosphatidylinositol 4-kinase (PI kinase) and PI 4-phosphate 5-kinase (PIP kinase), enzymes of the phosphatidylinositol phosphorylation pathway which leads to the production of second messengers. IP3 and DAG. In liver of normal male, adult, fed Wistar rats the steady state activity of PI kinase was 0.5 +/- 0.01 and that of PIP kinase was 0.046 +/- 0.003 nmol/hr/mg protein. The concentration of IP3 was 1.8 +/- 0.1 pmol/mg protein. 2. That the two kinases have short half-lives was observed in starvation. where in the rat liver or bone marrow activities rapidly decreased and on refeeding were restored in a day. Injection to rats of the protein synthetic inhibitor, cycloheximide, yielded t1/2 = 80 min for the two enzymes in bone marrow and t1/2 = 80 min in liver. 3. Linkage of the signal transduction enzymes with proliferation was shown by the high activities as compared to liver of these enzymes in rat organs of high cell renewal capacity, e.g., thymus, bone marrow, spleen and testes. 4. Linkage with malignant proliferation was indicated by the observation that in rat hepatomas the enzyme activities increased 5- to 9-fold and were highest in rapidly growing hepatoma 3924A (29- and 45-fold). 5. In human primary ovarian carcinoma PI and PIP kinase activities were elevated 4.4 and 2.9-fold, respectively, and in OVCAR-5 cells, 32- and 11-fold, respectively. Similar increases were observed in MDA-MB-435 human breast carcinoma cells in comparison with normal breast parenchymal cells. 6. The linkage of signal transduction enzyme activities with malignant proliferation was also observed in experiments when human breast carcinoma cells were plated in flasks and expressed their proliferative capacity in the log phase. PI and PIP kinase activities steadily and coordinately increased to a peak 11-fold rise in mid-log phase. In late log and plateau phases the kinase activities gradually declined to the starting level. Similar observations were made for the two enzymes in human ovarian carcinoma OVCAR-5 cells and in rat hepatoma 3924A cells in tissue culture. 7. In animals injected with cycloheximide the bone marrow PI and PIP kinase activities exhibited t1/2 = 0.12 hr, the shortest decay rate in comparison with 8 enzymes of purine and pyrimidine biosynthesis with t1/2 = 0.6 to 4.3 hr. 8. Injection of tiazofurin decreased PI and PIP kinase activities in the bone marrow with t1/2 = 82 and 78 min, respectively.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Regulation of signal transduction. 757 37

The spectrum of p53 mutations differs among human cancer types. We have hypothesized that the p53 mutational spectrum observed in particular tumor types reflects the functional ability of different p53 mutants to modulate wild-type (WT) p53-dependent gene transcription. Missense p53 mutants representing several mutational hotspot codons were cotransfected with WT p53 and analysed for their effects on p53-dependent transactivation of a reporter construct containing a specific p53 binding sequence (PG13-CAT) in human tumor cell lines lacking endogenous p53. Our results show that the ability of p53 mutants to inhibit WT p53-mediated transactivation is cell type dependent. In cell lines derived from a lung adenocarcinoma and a mesothelioma, the transactivation function of WT p53 was strongly inhibited by all p53 mutants examined. However, in cell lines derived from a prostate carcinoma and an osteosarcoma, the mutants examined generally had only minimal dominant negative effects. In cell lines derived from a hepatocellular carcinoma and an ovarian carcinoma, two mutants (248trp and 273his) enhanced WT p53-mediated transactivation of the reporter construct. Additional mutants retained the ability to inhibit WT p53-mediated transactivation in these cell lines. In addition, in a series of four breast tumor cell lines, the p53 mutants examined had similar effects on WT p53 transactivation ability including enhanced transactivation activity in the 273his cotransfectants. The p53 mutants were incapable of transactivating the PG13-CAT reporter in the absence of WT p53 expression. Therefore, the dominant negative effects of p53 mutants on WT p53 function may vary depending on the particular cell type. In addition, mutants with stronger inhibitory capabilities may confer a selective advantage during the tumorigenic process.
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PMID:Effects of p53 mutants on wild-type p53-mediated transactivation are cell type dependent. 778 55

We developed transgenic rabbits with a DNA construct containing the proto-oncogene c-myc conjugated to the Ig kappa-chain enhancer gene, E kappa. One of four transgenic rabbits was mated to a normal rabbit and we used the offspring to develop a colony of rabbits carrying the E kappa-myc transgene in their germline. Of a total of 19 E kappa-myc transgenic rabbits, eight developed tumors. The tumors were characterized histologically and four were diagnosed as lymphoma, and one each was diagnosed as embryonic carcinoma, hepatoma, ovarian carcinoma and basal cell carcinoma. By Southern analysis, we showed the four lymphomas were of B-lymphoid lineage and by nucleotide sequence analysis we found three of them most likely used VH1 in their VDJ gene rearrangements. Cells from the embryonic carcinoma, the hepatoma and two of the B-lymphomas were adapted to tissue culture. We discuss the possibility that tumors of non-lymphoid origin develop in the E kappa-myc transgenic rabbits because of the potential for NF-kappa B to activate the kappa-enhancer in cells other than B-lymphoid lineage cells.
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PMID:Lymphoid and non-lymphoid tumors in E kappa-myc transgenic rabbits. 780 3

Radiolabeled monoclonal antibodies (MAbs), by virtue of their tumor specificity, offer the prospect of localized, highly targeted radiation treatment of malignant tumors. To date, a large number of radioimmunotherapy (RIT) studies have been reported in experimental and clinical settings showing the potential of this therapeutic strategy. This includes RIT-trials in hepatoma, cholangiocarcinoma, ovarian carcinoma, brain tumors, melanoma, neuroblastoma and especially Hodgkin's and non-Hodgkin's lymphomas. Despite very promising results in some of these studies, radioimmunotherapy is currently still in a developmental status. Selective accumulation of MAbs at tumor sites-a prerequisite for effective radioimmunotherapy-is a complex process. Many factors such as antigen heterogeneity, distinct antibody features (affinity, subclass, fragment size, etc.), labeling techniques, tumor physiology and competing antigens were identified in the last years using theoretical and experimental tumor models. Strategies to improve these critical parameters are currently under investigation in order to increase the efficacy of radioimmunotherapy.
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PMID:[Systemic radiotherapy using monoclonal antibodies. Options and problems]. 831 39

In a previous paper (Radiat. Res. 127, 308-316, 1991), we reported that a moderately radiosensitive, transplantable murine ovarian carcinoma (OCaI) displayed apoptosis after irradiation whereas a radioresistant hepatocellular carcinoma (HCaI) did not. These initial observations have been followed up in this detailed analysis of the development of apoptosis in these two tumors as a function of time and dose. Histological sections of OCaI and HCaI carcinomas were scored at various times between 0.5 and 24 h after single doses of 2.5 or 25 Gy gamma radiation for the incidence of apoptosis. The percentage of nuclei undergoing apoptosis in untreated tumors was 5% in OCaI and 0.6% in HCaI. The peak in the number of apoptotic bodies occurred in the OCaI tumors 3-5 h after either dose. After 2.5 Gy, the peak incidence was about 20% and after 25 Gy it was about 30%. Irrespective of dose, HCaI tumors had an incidence of apoptosis of less than 3%. Based on the results of this time course, 4 h after irradiation was chosen for the determination of the dose response, over doses ranging from 2.5 to 25 Gy. The dose response for the OCaI tumors reached a plateau at 25-30% apoptotic nuclei after doses of about 7.5 Gy and above. Autoradiographic analysis of histological sections from mice injected with [3H]thymidine showed that some apoptotic bodies in the OCaI tumors arose from cycling cells. These results confirm that the apoptotic mode of cell death may represent an important response in some irradiated tumors.
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PMID:Development of apoptosis in irradiated murine tumors as a function of time and dose. 832 64

(1) Deoxycytidine kinase activity increased in a transformation- and progression-linked fashion in rat hepatomas of different proliferation rates. The activity also increased and was growth rate-linked in a series of tissue culture cell lines of human and animal tumors. (2) Deoxycytidine kinase activity was stringently linked with expression of the neoplastic proliferative program as it sharply increased in log phase in tissue culture cells of hepatoma 3924A and several human carcinoma strains. (3) Deoxycytidine kinase is subject to nutritional and hormonal regulation. On starvation the activity in liver decreased and on refeeding it returned to normal. Steroid hormone increased liver enzymic activity. Deoxycytidine kinase is substrate-inducible, since deoxycytidine injections in rat led to a 2- to 3-fold increase in hepatic enzyme activity. (4) Actinomycin or cycloheximide treatment blocked the increase in liver deoxycytidine kinase activity induced by steroid or deoxycytidine treatment. Therefore, it is assumed that the rise in deoxycytidine kinase activity requires new RNA and protein synthesis. (5) Cycloheximide treatment of rats carrying hepatomas yielded a t1/2 = 3.4 hr in the tumor for deoxycytidine kinase activity which was the shortest among the examined enzymes of purine and pyrimidine biosynthesis. (6) Actinomycin treatment of rats carrying hepatomas yielded a t1/2 of 5.8 hr for deoxycytidine kinase activity in the tumor which was one of the shortest in the examined enzymes of purine and pyrimidine biosynthesis. (7) Difluorodeoxycytidine (DFDC) is a competitive inhibitor (Ki = 7-28 microM) of deoxycytidine kinase from rat hepatoma and from human pancreatic carcinoma and ovarian carcinoma cells in culture.
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PMID:Regulation of deoxycytidine kinase activity and inhibition by DFDC. 835 16

Radiolabeled monoclonal antibodies have been used for radioimmunotherapy studies with human tumor spheroids and murine and human tumor xenografts in experimental animals. This paper reviews the work that has been performed in these models with different types of cancer, and highlights those papers that have presented dosimetry estimates and attempts to correlate the findings. Radioimmunotherapy studies in multicell spheroids, as a model for micrometastases, have been performed in human neuroblastoma, colon cancer, and melanoma cell lines using 131I-, 125I-, 186Re-, and 212Bi-labeled antibodies. The uniform geometry of the spheroid has allowed radiation dose estimates to be made. Up to three logs of cell kill have been achieved with 131I- and 186Re-specific antibody with minimal toxicity from labeled nonspecific antibody, but 212Bi-antibody had little effect because of its short half-life as shown by Langmuir. It appears that the two most important factors for therapeutic efficacy in this model are good penetration of the radiolabeled antibody and an adequate radionuclide half-life to allow penetration of the immunoconjugate prior to significant radionuclide decay. Radioimmunotherapy studies in animals bearing transplants of colon cancer, leukemia, lymphoma, hepatoma, renal cell carcinoma, neuroblastoma, glioma, mammary carcinoma, small cell lung carcinoma, cervical carcinoma, ovarian carcinoma, and bladder cancer have been performed with 131I, 90Y, 186Re, 153Sm, and 177Lu beta emitting, and 212Bi alpha emitting radionuclides conjugated to monoclonal antibodies. A few studies compared different radionuclides in the same model system. The approaches that have been used in these studies to estimate tumor dosimetry include the MIRD approach, thermoluminescent dosimetry, autoradiography, and comparison to external irradiation. The majority of investigators have estimated the dose to tumor and normal organs using MIRD-based calculations (time-activity curve and equilibrium dose constant method). The range of tumor doses has been between 17 and 11 171 mGy/MBq of administered radioactivity. The effectiveness of radiolabeled monoclonal antibody therapy depends on a number of factors relating to the antibody such as specificity, affinity, and immunoreactivity. The density, location, and heterogeneity of expression of tumor-associated antigen within tumors will affect the localization and therapeutic efficacy of radiolabeled antibodies, as will physiological factors such as the tumor vascularity, blood flow, and permeability. These factors are discussed and examples are presented.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Experimental radioimmunotherapy. 849 64


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