Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0027627 (metastases)
 103,950 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We have investigated the effect of the immunomodulator ubenimex (hereafter referred to as bestatin) on the enzymatic degradation of the extracellular matrix by human renal cell carcinoma SN12M cells during the invasive process. The invasion of SN12M cells into reconstituted basement membrane (Matrigel) was inhibited by the presence of bestatin in a concentration-dependent manner. However, bestatin did not have any effect on tumor cell adhesion and migration to the extracellular matrices which may be involved in tumor cell invasion. Bestatin inhibited the degradation of type IV collagen by tumor cells, but not by tumor-conditioned medium (TCM), in a concentration-dependent manner. We also found that bestatin inhibited hydrolysing activities towards substrates of aminopeptidases in SN12M cells. Since bestatin was found to inhibit aminopeptidase activity, the inhibition of tumor invasion by bestatin is likely to be associated with its action as an enzyme inhibitor. Bestatin only slightly inhibited tumor cell plasmin activity, which can lead to the conversion of the latent collagenase to the active form, but this slight effect was not significant. The zymography of TCM from SN12M cells showed that the treatment of tumor cells with bestatin resulted in the disappearance of the 68 kDa type IV collagenase-enzyme level (active form) and slight reduction of the 72 kDa type IV collagenase-enzyme level (latent form). These results indicated that bestatin may inhibit tumor cell invasion through a mechanism involving its inhibitory action on aminopeptidases in tumor cells, suggesting that the aminopeptidase may partly be associated with the conversion of a latent form of type IV procollagenase to an active form or the secretion of the collagenases from tumor cells.
Clin Exp Metastasis 1992 Jan
PMID:Inhibition of tumor invasion and extracellular matrix degradation by ubenimex (bestatin). 173 47

Bestatin is a potent inhibitor of aminopeptidase B, an enzyme which is found in abundance in the membrane of monocytes and macrophages. Binding of Bestatin to cells in the histiocytic linage upregulates colony stimulating activity (both in vitro and in vivo), which subsequently increases hematopoietic and hematologic values. We report that the treatment of mice with Bestatin upregulates the frequency and absolute numbers of colony forming unit--granulocyte-macrophage (CFU-GM), as well as the entry of CFU-GM into S phase (a measure of progenitor cell activity). As a result, there is an increase in bone marrow cellularity in cyclophosphamide myelosuppressed mice and an increase in the absolute neutrophil count in normal and myelosuppressed mice. The therapeutic application of this hematopoietic modulator has been demonstrated in combination cyclophosphamide and Bestatin protocols. While Bestatin has significant therapeutic activity for minimal metastatic disease, therapy models in which the hosts have greater metastatic tumor burdens requires combination chemoimmunotherapy for a significant therapeutic effect. Because myelosuppression as a therapeutic indication for Bestatin has only recently been recognized, few clinical studies have been undertaken with appropriate surrogates of hematopoietic activity. However, the preliminary clinical evidence of hematopoietic activity by this non-toxic dipeptide, as reviewed here, suggests that this may be an appropriate drug for the treatment of myelosuppressed patients. Thus, Bestatin as an orally active biological response modifier (BRM) has significant therapeutic activity for metastatic disease via multiple mechanisms including hematopoietic stimulation and macrophage activating properties.
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PMID:Hematopoietic and therapeutic properties of bestatin in normal and myelosuppressed mice. 191 71

Bestatin has significant therapeutic activity (even following oral administration) for the treatment of metastatic disease, an activity which is limited by tumor burden. Therefore, the therapeutic potential of bestatin was examined in combination with chemotherapy to determine if there is additive activity for heavy tumor burdens. Bestatin significantly increased therapeutic activity and decreased the myelotoxicity of cyclophosphamide following a single injection of cyclophosphamide or split daily doses. In immune function studies, in tumor-bearing animals, bestatin increased the number of colony-forming units (granulocyte-macrophage) (CFU) and alveolar macrophage tumoricidal activity. However, when bestatin was combined with cyclophosphamide, which depressed bone marrow and macrophage activity, it did not show apparent augmentation of macrophage and NK cell activity, but did significantly increase bone marrow CFU activity. Thus, in combined chemoimmunotherapy, bestatin appears to enhance therapeutic activity by accelerating the recovery of hematopoiesis. We suggest, therefore, that a combination chemotherapy protocol, with oral bestatin, may facilitate myelorestoration following aggressive chemotherapy. The majority of biological response modifiers require parental administration; thus, the identification of an orally active, synthetic immunoaugmenting agent with a defined receptor is of particular interest.
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PMID:Chemoimmunotherapy with cyclophosphamide and bestatin in experimental metastasis in mice. 275 91

Bestatin is a low molecular weight aminopeptidase inhibitor originally isolated from culture filtrates of Streptomyces olivoreticuli. The serum pharmacokinetics in mice are dependent on route of administration, with a short t1/2 (1.69 min t1/2 alpha and 12.8 min t1/2 beta), but a high initial serum level following i.v. administration. When administered via the i.p., s.c., i.m., or p.o. routes of administration, bestatin had serum t1/2 beta s of 8.56, 16.91, 19.25, or 15.4 min, respectively. The maximum area under the curve (concentration X time) occurred following i.v. and i.m. administration, with a lower level following p.o. or i.p. administration. Bestatin had therapeutic activity for experimental metastases, not only following i.v., i.p., and i.m. routes of administration but also following oral administration. Because of its brief serum t1/2, bestatin's therapeutic activity depends on aggressive (either daily or twice daily injection, especially following p.o. administration) and high-dose administration. Thus, the rate-limiting aspect of bestatin's therapeutic activity appears to be associated with its pharmacokinetics.
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PMID:Pharmacokinetics of bestatin and oral activity for treatment of experimental metastases. 290 81

In this report, we describe the immunomodulatory properties and therapeutic efficacy of bestatin. Macrophage activation, but not natural killer cell augmentation, was observed both in vitro and in vivo. Immunostimulation of T-cell activity was observed in assays of allogeneic mixed lymphocyte response, but cytotoxic effector cells did not develop after an allogeneic mixed lymphocyte-tumor cell culture. Bestatin also had T-cell adjuvant activity when it was admixed with a suboptimal vaccine composed of irradiated tumor cells. We observed significant therapeutic activity against preexisting experimental and spontaneous metastases when bestatin was administered at high doses per animal for 4 weeks.
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PMID:Immunomodulatory and therapeutic properties of bestatin in mice. 294 38

Bestatin was administered to 20 patients with urogenital tumors. The therapeutic results showed 12 surviving patients and 8 dead patients (including 7 due to cancer and 1 due to a cerebrovascular disorder). One patient has survived for 5 years since bestatin treatment of pulmonary metastasis of renal cancer, and one other patient achieved 5-year survival in spite of systemic metastases of testicular tumor. It is noteworthy that in earlier times these patients could have been expected to experience sudden relapse and aggravation, instead of the long-term survival recorded in this bestatin trial. Studies were conducted on the immunological parameters of the patients before and after the use of bestatin, and it was found that these parameters showed improvement as a result of the treatment. Even though bestatin was ingested for long periods of time by these patients, there was almost no development of adverse reactions to the treatment.
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PMID:[Clinical studies of bestatin on genitourinary cancer]. 398 76

Twenty one patients with advanced metastatic cancer of various types received 30 mg of Bestatin daily per os as a single treatment for several weeks. It was observed that the blood lymphocyte counts remained unchanged but the frequency of SRBC rosette forming cells increased and the frequency of lymphocytes possessing receptors for the Fc-part of IgG became normalized after two weeks of treatment. The frequency of lymphocytes possessing receptors for C'3 was not changed. The natural killer activity of peripheral lymphocytes for K562 and Chang cells increased but the PPD stimulation of the lymphocytes was not altered. A slight, but significant increase of the PHA stimulation of lymphocytes was observed after 4-7 weeks of Bestatin treatment. It is concluded that Bestatin is a nontoxic drug which changes the cellular composition as well as certain immunological functions of human lymphocytes.
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PMID:Changes of the blood lymphocyte population in cancer patients treated with bestatin, a new immunomodulator. A phase I study. 747 May 79