Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0684249 (lung carcinoma)
 23,830 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Base propenals arise from DNA by a Fe(II)-bleomycin-mediated reaction which leads to strand scission. These compounds undergo addition-elimination reactions with thiols and other nucleophilic groups under physiological conditions and form an addition product with glutathione. Thymine- and adenine-N1-propenals inhibit DNA synthesis in HeLa cells; both compounds are cytotoxic [50% inhibiting concentration (IC50) = 1 to 2 microM]. A structurally related nucleoside, thymidine-N3-propenal, designed as a metabolic pathway inhibitor, inhibits growth of HeLa, L1210 leukemia, Lewis lung carcinoma, B16 melanoma, and DLD-1 human colon carcinoma cells in culture (IC50 = 1 to 6 microM). A single injection of this compound, administered on the first day following transplant of L1210 leukemia cells, increased the mean survival time of mice by 50% (T/C = 154). Thymidine-N3-propenal selectively blocks DNA synthesis in HeLa cells and inhibits thymidine kinase (Ki = 5.1 microM) and DNA polymerase-alpha. We suggest that base propenals, rather than damaged DNA, account for some of the cytotoxic effects of bleomycin and that nucleoside propenals represent a novel class of site-directed inhibitors.
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PMID:Origin and cytotoxic properties of base propenals derived from DNA. 257 72

Glutathione S-transferase (GST) is a family of multimolecular forms with multi-functions for detoxication of drugs, and certain GST forms have been reported to concern multidrug resistance (MDR) mechanisms of neoplastic cells to anticancer drugs. In this paper, recent studies of GSTs concerning MDR are briefly reviewed, and the problems to be clarified are discussed. The reduced glutathione (GSH) is known to play important roles in the inactivation (detoxication) of the anticancer drugs. Most of them, especially alkylating agents, are conjugated with GSH by GSTs and detoxified, and the peroxides from drugs such as adriamycin are also reduced with GSH and detoxified by the GSH peroxidase activity of certain GST forms. Rat GST-P (GST 7-7) and human GST-pi, both of which belong to Class pi in the species-independent classification of GST, have been known as a marker enzyme for rat and human (pre) neoplastic lesions, respectively. GST-P is increased in rat hepatic preneoplastic foci resistant to cytotoxic agents. GST-pi is also increased not only in cancer cells such as colon carcinoma and non-small cell lung carcinoma, which exhibit "natural resistance" to anticancer drugs, but also increased in breast, ovarian and other tissue carcinomas with increased "acquired resistance" to certain drugs. A few research groups have attempted to confirm by transfection of a vector expressing a GST form such as GST-pi into non-resistant cell lines whether there is a direct relationship between the expression of a specific GST form and the appearance of MDR. However, MDR did not always appear. Recently, it was found in our laboratory that GST-P, GST-pi and even mouse GST II in Class pi, all are very strongly inactivated by SH-modifiers and active oxygens, indicating that these properties may be useful for overcoming MDR, if the forms really are involved with MDR.
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PMID:[Anti-cancer drug resistance and glutathione S-transferases]. 265 Jun 31

Clinically, 5-formyltetrahydrofolate (leucovorin, folinic acid, LV) in combination with 5-fluorouracil (5-FU) has been used at various doses, schedules, and routes of administration with therapeutic benefit to patients with advanced colorectal carcinoma and breast carcinoma. Clinical experiences have been primarily with LV doses of 25, 200, and 500 mg/m2 administered by either short-term intravenous infusion, daily continuous infusion, or orally. In patients with lung carcinoma, oral administration of dl-LV at 125 mg/m2 hourly for 4 hours (total dose of 500 mg/m2) gave the following peak plasma folate concentrations: dl-LV, 4.6 + 1.9 microM; 5-methyltetrahydrofolate, 4.3 + 2.1 microM; and no detectable l-LV in most cases. The d-LV/5-methyltetrahydrofolate ratios, however, were lower for the oral route than for the same dl-LV dose administered by 2-hour intravenous infusion in the same patient. To determine if there is a relationship between the dose, schedule, or route of administration and the therapeutic efficacy of LV combined with 5-FU, studies were carried out in rats with transplantable colon carcinoma. 5-Formyltetrahydrofolate was administered at various doses by either 2-hour infusion, 2-day continuous intravenous infusion, or by divided hourly oral doses for 4 hours. In all cases, the total doses of dl-LV administered were 100, 200, and 400 mg/kg. Data obtained to date indicate: (1) plasma folate concentrations by intravenous administration were dose dependent, but lower and saturable concentrations of folates were observed by oral administration; and (2) while the concentrations of 5-methyltetrahydrofolate achieved by the 2-hour infusion schedule were relatively constant and independent of the dose of dl-LV administered, conversion of dl-LV to 5-methyltetrahydrofolate with the 2-day infusion of 100, 200, and 400 mg/kg was dose dependent. In humans, however, conversion was independent of the route of administration of dl-LV (19% for the 2-hour infusion and 23% for the 5-day infusion of 500 mg/m2 dose). Preliminary results for antitumor activity of 5-FU in combination with dl-LV, administered by either 2-hour intravenous infusion (400 mg/kg/day for 5 days) or orally (100 mg/kg/hour for 4 hours), yielded similar inhibition of in vivo tumor growth, each being greater than what was achieved with 5-FU alone.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Toxicity and antitumor activity of 5-fluorouracil in combination with leucovorin. Role of dose schedule and route of administration of leucovorin. 278 77

The majority of human tumor cell lines are proficient in the repair of guanine O6-alkylations (designated Mer+) and are thus capable of preventing the cytotoxic effects of chloroethylating agents. It has been proposed that in these cells guanine O6-chloroethylations are rapidly removed by the enzyme O6-alkylguanine DNA alkyltransferase before the formation of DNA interstrand cross-links can occur. In this study pretreatment of four Met+ human cells (A2182 lung carcinoma, A375 melanoma, HT-29 colon carcinoma, and IMR-90 normal lung fibroblasts) with the DNA methylating agent streptozotocin apparently saturates the monoadduct repair system and allows mitozolomide to form interstrand cross-links in these cells. The inhibition of the alkyltransferase results in the continued presence of guanine O6-chloroethylations which then undergo a series of reactions that lead to DNA interstrand cross-link formation. As observed by colony forming assays, streptozotocin pretreatment causes a dramatic increase in the sensitivity of these four Mer+ cell lines to the cytotoxic effects of mitozolomide. These results indicate that a combination of streptozotocin pretreatment followed by mitozolomide may be useful in the treatment of human cancer.
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PMID:Combined effects of streptozotocin and mitozolomide against four human cell lines of the Mer+ phenotype. 294 76

The role of human tumor-derived immunoregulatory factors (IRF) in the suppression of murine in vitro cell-mediated immune systems was investigated. IRF was extracted from a fresh human colon carcinoma and a liposarcoma using 3 M KCl. These extracts have previously been shown to suppress in vitro human immune responses. Both IRF extracts inhibited PHA-stimulated murine splenocyte [3H]Tdr uptake in a dose-dependent manner while extracts of normal tissue were not inhibitory. To further investigate in vitro immunosuppression a (C57BL/6 X A/J) F1 anti-B10. BR mixed lymphocyte reaction (MLR) was developed. Optimal [3H]Tdr incorporation was on Day 4 with 1 X 10(5) responders and 2 X 10(5) irradiated stimulators. Addition of IRF caused a 56% inhibition of this response but did not alter the kinetics of the MLR response. Induction of cell-mediated cytotoxicity (C57BL/6 X A/J F1 vs B10.D2) was significantly inhibited by addition of IRF during in vitro sensitization. Release of 51Cr from P-815 targets was decreased to spontaneous release levels at an effector:target (E:T) ratio of 20:1 when IRF was present during sensitization. At this E:T ratio, cells sensitized in the presence of a normal muscle 3 M KCl extract or medium caused 71 and 60% 51Cr release, respectively. IRF activity could also reproducibly be extracted from two small cell lung carcinoma tissue culture lines grown under a variety of culture conditions or passaged in nu/nu mice. The biochemical characteristics of the factor inhibiting human and murine lymphoid cell proliferation were identical. Thus, this system provides a convenient model for assessing the activity of human tumor-derived immunoregulatory factors.
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PMID:Suppression of murine immunologic functions by fresh and cultured human tumor extracts. 298 65

We performed ultrastructural analysis on 70 consecutive patients with solitary cancers in lung with the following histologic classifications: adenocarcinoma (42 cases), bronchioloalveolar carcinoma (13), large cell carcinoma (4), and adenosquamous carcinoma (11). Of these 70 cases, nineteen (13 adenocarcinomas, 4 bronchioloalveolar carcinomas, and 2 adenosquamous carcinomas) contained cell surface microvilli with microvillous core rootlets and/or glycocalyceal bodies. Subsequent clinical followup revealed that three of these 19 cases were actually metastatic colon carcinoma. The remaining 16 patients are currently free of extrathoracic primary disease and are therefore, presumably, primary carcinoma of the lung. Since both primary and metastatic tumors showed cell surfaces with microvilli having core rootlets and glycocalyceal bodies, we conclude that the presence of these ultrastructural features does not always permit the distinction between primary and metastatic adenocarcinoma in lung.
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PMID:Limitations of the usefulness of microvillous ultrastructure in distinguishing between carcinoma primary in and metastatic to the lung. 302 33

Carcinomas produce elevated quantities of prostaglandins (PGs), particularly the E series, which can play an important role in the suppression of the cellular immune reaction in tumor-bearing individuals. These findings have raised the possibility that PG synthetase inhibitor can restore the immune activity against tumors. The anti-tumor activity of indomethacin, a potent PG synthetase inhibitor, was investigated in mice implanted with colon carcinoma 38, colon carcinoma 26 and Lewis lung carcinoma in a series of model studies for cancer treatment in man. Treatment with indomethacin substantially reduced the levels of PGs, particularly PGE2 in tumor tissue, inhibited the tumor growth, particularly the early stage of cell proliferation, prolonged the survival time, eliminated tumors in the abdominal cavity, and inhibited metastatic tumor recurrence after surgery. Also, the treatment reduced the growth of human gastric and colon carcinomas transplanted into nude mice. Thus, indomethacin might also be effective against human carcinomas. It is postulated that PG synthetase inhibitor may prove to be a good therapeutic tool effective against human cancer when used in combination with chemotherapeutic and other immunotherapeutic drugs as well as with low-dose radiation therapy.
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PMID:[Anti-cancer treatment with prostaglandin synthetase inhibitor in animal models]. 308 71

The growth-modulating effects of recombinant alpha- and beta-forms of human interleukin-1 (IL-1) and interferon-gamma (IFN-gamma) were examined with several human cell lines. Exposure to combinations of IL-1 and IFN-gamma resulted in three categories of cell response. The first was cell lines in which IL-1 stimulated growth and offset the growth inhibitory effects of IFN-gamma. These lines included the lung carcinoma CALU-1 and the colon carcinoma SW-48. The second was some of the cell lines that were refractory to IL-1 and that were inhibited by IFN-gamma alone. These included the cervical carcinoma HeLa, the transformed milk line HBL-100, and the myelogenous leukemia K562. The third group consisted of cells in which growth inhibition by IL-1 and IFN-gamma was additive. These included the mammary carcinomas MCF-7 and MDA-MB-415. The exception to this latter group was ME-180 in which significant additive inhibitory effects could not be demonstrated. IL-1 alone primarily induced a cytostatic effect in growth-inhibited cell lines. The cytolytic effect induced by IFN-gamma was increased in the presence of IL-1. The data support the conclusion that the effects on growth of IL-1 and IFN-gamma are mediated by different mechanisms.
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PMID:Modulation of cell proliferation by human recombinant interleukin-1 and immune interferon. 311 Apr 77

Sparsomycin (Sm) is a known inhibitor of ribosomal protein synthesis with an attractive anticancer potential. Recently, several analogues of Sm which are more active than the parent drug were selected for further study on the basis of in vitro investigations. Six analogues as well as the parent drug were tested for their antitumor activity in eight in vivo murine tumor models: P388 and L1210 leukemias, RC renal cell carcinoma, B16 melanoma, C38 colon carcinoma, LL Lewis lung carcinoma, C22LR osteosarcoma and M5076 sarcoma. Sm itself appeared to have only borderline activity on L1210 leukemia. The analogues that were most active in vitro showed also the highest in vivo activity. The most sensitive tumors were RC, L1210 and P388. Minimal activity was found on B16 and no activity on C22LR, M5076, C38 and LL. The most active compounds are deshydroxy-Sm, ethyl-deshydroxy-Sm and n-pentyl-Sm. There was a considerable loss of activity when L1210 leukemia was implanted sc while the drugs were administered iv. Only one drug, ethyl-deshydroxy-Sm appeared to be active in this assay. No single most effective compound could be found in this study. The overall activity of Sm and its analogues is moderate. The three analogues which show high activity in three ascitic tumors will be further investigated using human tumor xenograft models.
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PMID:In vivo antitumor activity of sparsomycin and its analogues in eight murine tumor models. 322 41

The effects of recombinant human interferon-alpha A/D (rIFN-alpha A/D, a subtype of recombinant human leukocyte interferon with biological activities against murine tumor cells) on the growth of murine tumors were studied. rIFN-alpha A/D significantly inhibited the growth of mouse M5076 reticulum cell sarcoma, MOPC-104E myeloma, colon carcinoma 26 and Meth A fibrosarcoma by dose-dependent fashion. rIFN-alpha A/D also inhibited the metastases and growth of Lewis lung carcinoma and showed a synergistic effect with combination of cyclophosphamide. The antitumor activity of rIFN-alpha A/D was observed by intra-muscular, intravenous, subcutaneous, intraperitoneal injections or by the injection at the site of the tumors.
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PMID:[Effects of recombinant human interferon-alpha A/D on the growth of experimental tumors in mice]. 330 69


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