Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0027651 (tumor)
 685,946 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Carmethizole hydrochloride [1-methyl-2-methylthio-4,5-bis(hydroxymethyl)imidazole-4', 5'-bis(N-methylcarbamate)hydrochloride, NSC 602,668; hereafter called carmethizole] is a new antitumor drug that has shown relatively broad activity in initial evaluations against several murine tumors and human tumor xenografts in vivo. The present studies were designed to address questions about carmethizole's activity against established disease, its activity on different treatment schedules, and the extent of its cross-resistance with established drugs. Human MX-1 mammary carcinoma, human NCI-H82 small-cell lung carcinoma, and human LOX amelanotic melanoma xenografts in athymic mice were used to determine the drug's activity against established disease; the NCI-H82 lung-tumor xenograft in athymic mice was used to explore its schedule dependence; and a series of drug-resistant murine leukemias provided an in vivo cross-resistance profile. When injected i.p., carmethizole exhibited antitumor activity against advanced-stage s.c. MX-1 mammary, s.c. NCI-H82 lung, and i.p. LOX melanoma xenografts and was as effective against established disease (MX-1 and LOX) as it was against early-stage disease (no data are available for early-stage NCI-H82). The therapeutic effect of carmethizole was not route-dependent, as was evidenced by the similar delays observed in tumor growth following i.p. and i.v. administration. The use of a split-dose schedule on a single day instead of one bolus injection yielded an increase in the total dose delivered, resulting in an increased delay in tumor growth. Murine leukemias resistant to vincristine (VCR), amsacrine (AMSA), or methotrexate (MTX) were not cross-resistant to carmethizole. However, murine leukemias resistant to doxorubicin (ADR), melphalan (L-PAM), cisplatin (DDPt), 1-beta-D-ara-binofuranosylcytosine (ara-C), and 5-fluorouracil (5-FU) were cross-resistant to carmethizole, suggesting that patients who have previously been treated with any of these agents might be less likely to respond to carmethizole than those who have had no opportunity to develop resistance to any of these compounds. We anticipate that the information derived from these studies may be useful in the design of clinical trials of carmethizole and may stimulate additional basic research on the mechanism of action of this new agent.
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PMID:Antitumor activity and cross-resistance of carmethizole hydrochloride in preclinical models in mice. 132 3

Aphidicolin, a reversible inhibitor of DNA polymerase alpha and delta, has recently been reported to reverse the resistance to cisplatin (DDP) of an ovarian cancer cell line. We investigated the pharmacokinetics of aphidicolin in mice and examined its activity either alone or in combination with DDP in the DDP-sensitive M5076 (M5) murine reticular cell sarcoma as well as in a DDP-resistant subline (M5/DDP). The drug was cleared from plasma very rapidly (clearance, 41.6 ml min-1 kg-1), showing a half-life of 15 min. Aphidicolin concentrations in the tumor were approximately 50% of those found in plasma at steady state. Using several dose schedules and continuous infusions we failed to detect significant antitumor activity for aphidicolin glycinate. Potentiation of the activity of DDP by aphidicolin glycinate was moderate in mice bearing M5 tumor as well as in those bearing M5/DDP tumor. These data do not support the possible clinical use of aphidicolin in combination with DDP. However, further studies should be carried out in different tumor models before this possibility is conclusively ruled out.
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PMID:Activity of aphidicolin glycinate alone or in combination with cisplatin in a murine ovarian tumor resistant to cisplatin. 139 2

A twofold change in the cisplatin (DDP) sensitivity of 2008 human ovarian carcinoma cells is sufficient to reduce tumor response in vivo. The DDP sensitivity of these cells can be enhanced by activation of the epidermal growth factor and protein kinase C signal transduction pathways. We report here that two endogenous growth factors, bombesin and tumor necrosis factor alpha (TNF alpha), enhanced DDP sensitivity by factors of 1.7 +/- 0.1 (SD)-fold and 1.8 +/- 0.1 (SD)-fold, respectively. Both agents also produced sensitization in an 11-fold DDP-resistant 2008 subline. Neither bombesin nor TNF alpha changed the accumulation of DDP, glutathione content, or glutathione-S-transferase activity in 2008 cells. However, a 2-h exposure to both bombesin and TNF alpha was sufficient to increase 2008 cloning efficiency by up to 2.6 +/- 0.1 (SD)-fold and 2.2 +/- 0.1 (SD)-fold, and it increased average colony size by 1.35 +/- 0.1 (SD)-fold and 1.55 +/- 0.1 (SD)-fold, respectively. Bombesin increased intracellular free calcium, and this was blocked by the bombesin receptor-specific antagonist SC196, demonstrating that 2008 cells have functional bombesin receptors. These results indicate that bombesin and TNF alpha can enhance sensitivity to DDP in both DDP sensitive and resistant variants of a human ovarian carcinoma and that both agents serve as growth factors for this tumor.
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PMID:Modulation of cisplatin sensitivity and growth rate of an ovarian carcinoma cell line by bombesin and tumor necrosis factor-alpha. 140 Oct 76

Osteosarcoma includes several distinct varieties. It is therefore essential to rely upon a very specialized pathologist. It is necessary to stage the tumor and to histologically define the oncologic quality of the surgical removal (surgical margins). The limb salvage surgery in osteosarcoma involves several areas of risk: the biopsy, the extension of the tumor in the marrow spaces and canal, the impingement or plugging of the vessels by the tumor, the invasion of the joint tissues, the contamination of the joint space and/or soft tissue compartments. The reconstruction after bone segmental resection involves many problems, including long-lasting prostheses, bone bank, microsurgical techniques--the preoperative chemotherapy dramatically reduced the need for amputation, in favour of conservative surgery. A good response to chemotherapy (almost total necrosis of the tumor), is the most important factor correlated with a favorable prognosis. The more recent protocols aim to increase the tumor response and the survival rate through a very intense primary chemotherapy, using Adriamycin, high-dose Methotrexate, Cisplatin and Ifosfamide.
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PMID:[Osteosarcoma]. 141 68

To investigate the mechanisms by which 3-aminobenzamide (3AB) reverses cisplatin (DDP) resistance in a rat ovarian tumor cell line, the effects of 3AB on DDP-induced DNA damage and repair were kinetically determined over a post-exposure period of 48 h. DNA single strand breaks (SSB) occurred maximally 12 h and 24 h following DDP exposure in DDP-resistant (O-342/DDP) and -sensitive (O-342) rat ovarian tumor cells, respectively. 3AB, present during and after the exposure, significantly increased SSB formation by DDP at 24 h (P < 0.02) and 48 h (P < 0.01) in O-342/DDP cells. To a lesser extent (P > 0.05), a similar tendency was also observed in O-342 cells. Formation of DNA interstrand cross-links (ISCL) by DDP reached a maximum by 12 h in either O-342 or O-342/DDP cells, but in the resistant cells they were both much lower and more rapidly removed. 3AB decreased ISCL in the sensitive cells at 12 h and thereafter with a maximum at 24 h (P < 0.05), while in the resistant cells the same treatment decreased ISCL at 12 h, had no effect at 24 h and increased ISCL at 48 h following DDP treatment. Therefore, it is concluded that 3AB has multiple effects on DNA damage and repair induced by DDP in both cell lines and increase of DNA-ISCL by 3AB at 48 h after the exposure in O-342/DDP cells might be related to its chemosensitizing effect in this line.
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PMID:Multiple effects of 3-aminobenzamide on DNA damage induced by cisplatin (DDP) in DDP-sensitive and -resistant rat ovarian tumor cell lines. 142 42

The antitumor effect of tumor necrosis factor (TNF) in combination with Cis-diammine-dichloroplatinum (II) (Cisplatin) upon implanted bladder carcinoma (MBT-2) in mice was analysed together with the toxicity. Mice were implanted into the bladder wall with about 10(4) cells MBT-2 viable cells. TNF was the purified human natural tumor necrosis factor. The antitumor effects were evaluated by the volume of the tumor thus implanted and the drug-toxicity by the body weight of mice and microscopic as well as macroscopic findings of the main organs. As a result, 1) The toxicity of TNF to mice was not enhanced in a dose-dependent fashion when combined with Cisplatin. 2) The antitumor effect by combination of TNF and Cisplatin was significantly increased compared to control group. 3) The effects of TNF was enhanced in a dose-dependent fashion when combined with Cisplatin. 4) The antitumor effects was confirmed by pathological findings. These results suggest that the combined use of n-TNF and Cisplatin is promising as a clinically effective treatment against bladder cancer in human.
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PMID:[Antitumor effect of combined use of purified human natural tumor necrosis factor (N-TNF) and cis-diamminedichoroplatinum (II) (cisplatin) on the implanted bladder carcinoma (MBT-2) in mice]. 143 74

The synergistic effect of local hyperthermia (LHT) with intratumor injection (i.t.) of cis-diamminedichloroplatinum (II) (DDP) was studied using a rodent model with implanted B16 melanoma tumors. The hindfoot of the C57BL/6 mouse bearing the tumor was placed in a water bath at 42.5 +/- 0.2 degrees C (intratumor temperature was at 42.3 +/- 0.1 degrees C) for 30 minutes just after local (i.t.) or systemic (intraperitoneal;i.p.) administration of DDP (1-3 mg/kg once in experiment I and 1-3 mg/kg three times in experiment II). The tumor growth ratio (TGR) at 7 days after treatment in the group given DDP 3 mg/kg (i.t.) with LHT was 1.1 in experiment I and 0.5 in experiment II, and there was a statistically significant difference in both experiments compared to findings in other groups (P < 0.01). The mean survival time was 42.1 days in experiment I and 50.2 days in experiment II, with a significant difference in the latter (P < 0.001). Thus regional injection chemotherapy given concomitantly with local hyperthermia promotes the anticancer effects and improves the prognosis without either severe renal injury or the promotion of hematogenic metastasis.
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PMID:Synergistic effects of intratumor administration of cis-diamminedichloroplatinum(II) combined with local hyperthermia in melanoma bearing mice. 143 45

We evaluated the efficacy of folinic acid (Leucovorin, LV) on cell lethality induced by 5-fluorouracil (FU) alone or in combination with cisplatin (DDP) by using the HEp-2 laryngeal squamous carcinoma multicellular tumor spheroids (MTS) system. For LV, non-toxic concentration of 10(-5) M was used. For cells in the monolayer, 6 and 24 h exposure to LV increased FU-induced cell lethality approximately 7- and 2-fold, respectively, whereas LV did not influence the effect of FU for MTS. LV's lack of effect on cells in MTS may be interpreted to mean that LV cannot penetrate the MTS. For the monolayer, simultaneous exposure to 3 drugs, DDP, FU and LV, produced synergistic interaction. However, sequential exposures were marginally synergistic or antagonistic, irrespective of sequence of DDP first or last. In contrast, DDP followed by FU plus LV was most synergistic for MTS. Simultaneous exposure was also synergistic, however, FU plus LV followed by DDP was antagonistic. These results suggest that LV is unable to penetrate into the MTS core to potentiate FU activity. DDP appears to have enhanced LV penetration into the MTS core. The exploration of means to overcome limited penetration of LV appears important for successful treatment of head and neck carcinoma.
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PMID:Effects of folinic acid on 5-fluorouracil induced cell lethality with or without cisplatin against head and neck laryngeal squamous carcinoma multicellular tumor spheroids. 144 99

The EORTC Brain Tumor Group has conducted 5 randomized and prospective phase-III trials in adults with supratentorial malignant gliomas testing the following adjuvant treatments: 1) CCNU 130 mg/m2, q.6 weeks (trial 26741); 2) VM-26 100 mg/m2 on day 1, plus CCNU 130 mg/m2 on day 2, q.6 weeks, given either during radiation therapy (trial 26751) or during 12 weeks prior to irradiation (trial 26841); 3) Misonidazole 12 mg/m2 total dose in 9 fractions (trial 26801); 4) Cisplatin 60 mg/m2 on days 1, 8, 15 and 21 of radiation therapy (trial 26851). None of these treatments did prolong significantly the survival nor the time to recurrence. The most powerful prognostic factors found in every trial were tumor pathology, patients' age and neurological status. Objective remission lasting 6 to 9 months, defined as a clinical improvement persisting after discontinuation of corticosteroids, was observed with CCNU, VM26 plus CCNU or HeCNU in approximately 20% of the patients, while 30% stabilized on HeCNU. The activity of procarbazine, AZQ or DDMP used as single agents was much lower.
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PMID:[Chemotherapy of malignant glioma. Results of studies of the EORTC group of brain tumors]. 144 63

When tumor cell density increases, the cytotoxic activity of certain anticancer agents, such as vincristine (VCR) and doxorubicin (DXR), progressively decreases. This phenomenon is termed the inoculum effect. Since VCR and DXR are less active in an acidic environment, we questioned whether the inoculum effects could have resulted from acidification of the medium that may have developed due to the high cell density. However, measurements of the cytotoxic activity of these agents in a pH-controlled medium revealed only a minor correction of the inoculum effects. Second, we wondered whether the inoculum effects that occurred at the high cell density might have been attributable to insufficient amounts of drugs to bind all the binding sites of the cells. To test this hypothesis, we used drug-resistant sublines, which required higher VCR or DXR concentrations for cell killing than did the parent cell line. When higher drug concentrations were used, the dose-response curves generated for low- and high-density cell populations became closer and overlapped each other, resulting in virtual disappearance of the inoculum effects. Measurements of cellular drug levels revealed that at a high cell density, cells accumulated much smaller amounts of both VCR and DXR in parallel with the positive inoculum effect. In contrast, when high concentrations of the drugs were used in drug-resistant cells, differences in the cellular drug contents between low and high cell densities became narrow. Cisplatin (DDP) belongs to a group of drugs that do not produce inoculum effects, and DDP's cytotoxic effects were not influenced by the pH-controlled medium or by the use of drug-resistant cell lines. These observations indicate that the inoculum effects are the result of the unavailability of VCR or DXR molecules to all cellular binding sites when cells at high densities are exposed to drugs. The drug concentration relative to cell density was apparently the major determinant for the inoculum effects seen in VCR- or DXR-induced cell killing.
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PMID:Relationship between tumor cell density and drug concentration and the cytotoxic effects of doxorubicin or vincristine: mechanism of inoculum effects. 145 60


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