Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0035412 (rhabdomyosarcoma)
 6,156 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

When methionine (Met), an essential amino acid, was substituted for by its precursor homocysteine (Hcy) in the culture medium, normal cells such as fibroblasts proliferated normally. In contrast, many tumor cells failed to grow or grew at a lower rate. Met dependency is acquired simultaneously with cell transformation, as observed with HBL 100, a human mammary epithelial cell line that acquired increased malignancy as a function of in vitro passage number, and NIH/3T3 (J10), a mouse fibroblast line transformed by transfection with the human HRAS oncogene. A relationship was observed between Met dependency and metastatic potential of the RMS-21, RMS-S4T, and RMS-J1 sublines derived from RMS-0, a rat rhabdomyosarcoma cell line: the higher the metastatic potential of the cell line, the higher the concentration of Met required to maintain its proliferation. Met-independent cells derived from the RMS-0 line, obtained by a progressive decrease of Met in the culture medium lost their tumorigenicity when injected into rats fed with Met-deprived diets. In addition, the in vitro motility of RMS-S4T tumor cells, a marker of metastatic capability, decreased in Met-free Hcy-complemented (Met- Hcy+) medium. Similarly, RMS-0 tumor cells, preincubated in a Met- Hcy+ culture medium for 24 hours, evidenced a decreased capacity to form lung colonies when injected into syngeneic rats: the median number of lung colonies was 27 and 3 (P less than .05) for cells cultivated in Met+ Hcy- and Met- Hcy+ media, respectively. An amino acid-defined mixture reproducing casein composition was used as a protein source in the diets fed to RMS-J1 tumor-bearing rats. Dietary substitution of Hcy for Met (i.e., met deprivation) resulted in decreased tumor growth (from 44.4 +/- 1.0 to 40.6 +/- 1.4; P less than .05) and prevention of metastatic spread (from 37 to 0; P less than .05). In conclusion, exogenous Met can be substituted for Hcy to maintain the survival of normal cells but is essential for tumor cell growth in vivo as well as in vitro. Therefore, this defect of cancerous versus normal cells could be used for a therapeutic purpose.
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PMID:Methionine dependency of malignant tumors: a possible approach for therapy. 202 74

In malignant cells the amino groups of cellular proteins are alkylated by homocysteine thiolactone, forming homocysteinyl peptide bonds. In normal cells the sulfur atom of homocysteine thiolactone is converted to homocysteic acid, phosphoadenosine phosphosulfate, and sulfate ester. N-substituted derivatives of homocysteine thiolactone synthesized from arachidonic acid, pyridoxal, and maleimide were previously found to have antineoplastic activity. Another N-substituted derivative, the rhodium trichloride complex of oxalyl homocysteine thiolactone, was synthesized and tested for antineoplastic activity. Mice with transplanted rhabdomyosarcoma were injected with solutions of the complex dissolved in lipids. Doses of 50 and 100 mg/kg per day for two weeks produced 50% inhibition of tumor growth. At doses of 100 and 200 mg/kg per day in tumor-free mice there was decreased survival, peritoneal reaction, pigment deposition in lung, fibrocalcific pericarditis, and leiomyosarcoma of colon (in one animal). The conclusion is that the complex of rhodium trichloride and oxalyl homocysteine thiolactone possesses antineoplastic activity.
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PMID:Antineoplastic activity of a rhodium trichloride complex of oxalyl homocysteine thiolactone. 358 Sep 45

N-homocysteine thiolactonyl retinamide was synthesized from trans retinoic acid and the free base of homocysteine thiolactone. In doses of 90-1800 mg/kg given i.p. in mixed lipid vehicle over nine weeks, the compound decreased to 60% of controls the number of lung tumors which was induced in A/J mice by 20 mg of ethyl carbamate. The highest dose also decreased the mean volume of lung tumors to 50% of controls, resulting in a total tumor volume of 30% of controls. Retinoic acid itself at 450 mg/kg was toxic, and no chemopreventive activity was observed. The free base and the lipophilic perchlorate salt of homocysteine thiolactone both increased the number of lung tumors to 114-117% of controls, indicating a co-carcinogenic effect. In C57BL/6N mice with transplanted MUO4 rhabdomyosarcoma, N-homocysteine thiolactonyl retinamide in a dose of 1000 mg/kg given over 11-21 days decreased the weight of the tumors to 30-70% of controls. These results show that N-homocysteine thiolactonyl retinamide has chemopreventive activity against chemical carcinogenesis and antineoplastic activity against a transplanted neoplasm.
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PMID:Chemopreventive and antineoplastic activity of N-homocysteine thiolactonyl retinamide. 365 91

Many Experimental and human tumor cell lines have been previously described as being dependent upon exogenous methionine for their in vitro proliferation. The rationale of the experiments described herein was to decrease the in vivo growth of malignant tumors by reducing the exogenous methionine available in diets fed to Wistar AG rats bearing the highly metastatic rhabdomyosarcoma, RMS-J1. The methionine content in the diet was reduced either by replacing casein (diet 1) with soybean protein (diet 4), or by lowering the amount of soybean protein in the diet (from 23 g/100 g to 12 g/100g) (diet 5), or by using a crystalline amino acid-defined mixture as the source of protein (diet 7). In the latter diet homocysteine replaced methionine and allowed the survival of the animals. Diet 4 significantly reduced the mean number of lung metastases without affecting the primary tumor growth. Treatment of RMS-J1 bearing rats with diet 5 led to the decrease of pulmonary invasion (78 and 21 median lung metastases, respectively, in control and treated groups). This diminished metastatic dissemination resulted from the reduced methionine consumption: the lowered casein content in diet 3 (10 g/100 g) as compared to diet 1 (23 g) did not alter primary tumor growth or the amplitude of lung invasion. Moreover, the addition of methionine to diet 5 prevented the diminution of the median number of lung metastases. Replacement of methionine with homocysteine in the crystalline amino acid-defined mixture (diet 7) fed to RMS-J1 bearing rats led to a limited retardation of primary tumor growth (less than 10%) and to a significant decrease in pulmonary invasion: the median number of pulmonary metastases was 28 and 9 for control and treated rats respectively.
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PMID:Decreased rat rhabdomyosarcoma pulmonary metastases in response to a low methionine diet. 367 75

The antineoplastic activity of N-maleamide homocysteine thiolactone amide (MHTA) encapsulated within liposomes was studied in mice with transplanted tumors. Tumor weight was decreased by 4-5 biweekly intraperitoneal injections of MHTA in liposomes in DBA/2N females with MTG mammary adenocarcinoma (35% of control value, P less than 0.005) and in C57B1/6N males with MUO4 rhabdomyosarcoma (11% of control value, P less than 0.0000001). Tumor incidence was reduced from 84 to 63% (P less than 0.05) and from 100 to 32% (P less than 0.001) in the two systems, respectively. When the compound was administered in dimethyl sulfoxide to A/HeJ females with A10 mammary adenocarcinoma by daily intraperitoneal injection, tumor weight was reduced to 70% of control value (P less than 0.05), and there was no decrease in tumor incidence (100%). No toxicity was observed at the therapeutic dose utilized, 10 mg/kg/day. N-Maleamide homocysteine thiolactone amide is a derivative of the normal biochemical constituents, maleic acid and homocysteine thiolactone. The results show that the N-substituted maleamide derivative of homocysteine thiolactone decreases the growth of murine tumors of two different histological types, when administered encapsulated within liposomes.
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PMID:Antineoplastic activity of N-maleamide homocysteine thiolactone amide encapsulated within liposomes. 403 35