Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0598934 (tumor growth)
 58,965 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Cancer patients have the highest prevalence of malnutrition of any group of hospitalized patients. The potential causes of this malnutrition are numerous, as elements of both starvation and stress are evident in the cancer-bearing host. The presence of the tumor alone may lead to reduced intake of nutrients and treatment modalities of surgery, chemotherapy, and radiation therapy further exacerbate nutritional deficits. It is clear that the tumor requires energy substrates to grow, and that these substrates are exacted from the host. Animal studies identify progressive nutritional depletion concomitant with increasing tumor growth during ingestion of a regular diet. This appears predominantly due to reduced dietary intake in addition to host metabolic alterations. In animal/tumor models deliberate dietary protein depletion results in severe host weight loss, but also causes diminished tumor growth rates. Dietary manipulation in these animal/tumor models have demonstrated methods of improving tumor response to chemotherapy by manipulation of tumor growth rates. In addition, drug-pharmacokinetics have been altered by dietary manipulation. However, data from animal/tumor models are not directly applicable to man since the tumor in animals usually results in the death of the host within six to eight weeks. Nevertheless, controlled laboratory studies in animals provide basic metabolic information which promotes understanding of host/tumor relationships in man. In cancer patients malnutrition has prognostic value, leads to a distortion of body composition with erosion of body protein and fat stores, and compromises the delivery of adequate therapy. There is no direct objective evidence of accelerated tumor growth in humans with cancer who receive nutritional support as part of their treatment regimen. The host benefits to the extent that body composition is at least maintained during the period of nutritional repletion. Thus, nutritional support provides support to the patient during periods of treatment and dietary deprivation. No improvement in the tumor's response to therapy, however, has been demonstrated by this approach.
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PMID:Nutritional support in the cancer-bearing host. Effects on host and tumor. 309 53

During tumor growth, there are characteristic alterations in the concentration and synthesis of various plasma proteins. The purpose of this study was to evaluate whether these changes are unique to a tumor-bearing state, or rather, they represent a generalized response to a paraneoplastic state mediated by the release of monokines or protein-calorie malnutrition. Plasma protein synthesis and concentrations in mice bearing a transplantable fibrosarcoma were compared to animals receiving either a terpentine abscess, Corynebacterium parvum administration, calorie-protein depletion, or administration of the recombinant-derived monokines, murine interleukin 1 alpha or human tumor necrosis factor-alpha. Tumor-bearing animals showed a significant increase in total plasma protein synthesis that was similar in magnitude to the increase seen following a terpentine abscess or after administration of interleukin 1 or tumor necrosis factor-alpha. Similarly, the pattern of protein synthesis and concentration, as determined by isoelectric focusing or sodium dodecyl sulphate-polyacrylamide gel electrophoresis, were similar, albeit not identical, among tumor-bearing animals and those receiving either a terpentine abscess, C. parvum and monokine administration. Serum amyloid P concentrations were markedly elevated in tumor-bearing animals, as they were in animals after a sterile abscess and following interleukin 1 administration, as well as to a lesser extent tumor necrosis factor-alpha administration. We can therefore conclude that the majority of changes in plasma protein concentration and synthesis seen in this tumor-bearing model are similar to those seen during an acute inflammation and can be reproduced to a large extent by the administration of the monokines, interleukin 1 alpha or tumor necrosis factor-alpha.
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PMID:Plasma protein synthesis in experimental cancer compared to paraneoplastic conditions, including monokine administration. 311 56

The effect of a protein-free diet (PF) or a restricted intake of chow (RI) and subsequent host repletion with total parenteral nutrition (PF-TPN, RI-TPN) on tumor growth and polyamine metabolism of fibrosarcoma-bearing rats was examined. Host weight was significantly reduced by PF and RI. Tumor growth was reduced in malnourished rats with the PF regimen resulting in the greatest decrease. Rats receiving TPN after 14 days of the RI or PF regimens had higher host weight and plasma albumin levels than malnourished rats. Tumor growth during TPN was evaluated as the percent increase and compared with that of the respective malnourished rats. The percent increase for RI-TPN rats was significantly greater although a trend toward an increase was also evident for PF-TPN rats. Tumor ornithine decarboxylase (ODC) activity and putrescine levels were increased for PF rats and decreased for RI rats while tumor ODC activity was consistently increased by TPN. Tumor growth, ODC activity, and putrescine levels were simultaneously increased only for those rats fed the RI regimen prior to TPN. These results show a disparity in tumor ODC activity, putrescine levels, and tumor growth in malnourished rats. The results of this study suggest that the nutritional origin of cachexia influences the response of the tumor to TPN and emphasizes the importance of considering the methods to induce malnutrition in designing therapuetic regimens.
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PMID:Influence of total parenteral nutrition on tumor growth and polyamine biosynthesis of fibrosarcoma-bearing rats after induced cachexia. 314 39

Generalized malnutrition results in inhibition of tumorigenesis and tumor growth in experimental animal models. Neither the specific nutrient deficiency nor the mechanism has been definitely elucidated. We have shown previously that dietary sodium deprivation in rapidly growing rats retards protoplasmic growth. This effect was correlated to the extracellular fluid (ECF) volume expansion which is dependent on sodium accumulation. Since solid tumors are composed of a large quantity of ECF (which includes plasma volume) it was postulated that preventing the accumulation of new ECF by means of sodium restriction would influence tumor growth. The present study was designed to determine the effects of salt restriction on tumor growth and to relate these effects to ECF volume. Approximately 10(6) viable B16 melanoma cells were injected into C57BL/6 x DBA/2 F1 and C57 mice. A salt restricted diet (sodium less than 3 microeq/g) was provided ad libitum. The drinking solution was distilled water for the experimental group and 0.45% saline solution for the controls. There was a significant decrease in tumor growth rates during sodium restriction. The total body ECF volume increased when dietary sodium was supplied but did not change during salt restriction. Therefore, the only source for the ECF in the tumor mass was from nontumorous tissue. We conclude that during dietary sodium restriction solid tumor growth is retarded and can proceed only to the extent that ECF is released from cachectic body tissues.
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PMID:Restriction of tumor growth in mice by sodium-deficient diet. 337 Jun 41

Nutritional deficiencies are believed to be instrumental in producing reduced immune responses in a variety of animal species. Malnutrition may result in an increase or a decrease in immune functions, depending upon its degree, and also the timing and severity of the nutritional protein deprivation. Our experimental data suggest that there is a significant impairment of cytotoxic activity against K-562 and of the ability of spleen cells to produce interferon in protein-deprived mice in comparison with control mice. Paradoxically accelerated tumor growth after administration of OK-432 or Lentinan was also noted in protein-deficient tumor-bearing mice. In addition, a clinical randomized study of advanced or recurrent gastric cancer patients treated with MMC and FT(MF) with or without lentinan was performed. We recognized excellent end-point results only in the lentinan-treated patients with normal protein levels, while no effect of this agent was seen in patients with low serum protein levels (below 5.9/dl). Aggressive postoperative chemotherapy for cases with distant lymph node metastasis was performed under active nutritional support without any depression of metabolic and immunological states, resulting in a good 5-year survival rate (36.9%).
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PMID:[Anti-cancer effects of BRMs associated with nutrition in cancer patients]. 338 33

Plasma levels of growth hormone (GH) and the effect of GH treatment have been evaluated in adult nongrowing sarcoma-bearing mice (C57BL/6J). Prepubertal tumor-bearing mice, tumor-bearing hypophysectomized Sprague-Dawley rats, and malnourished non-tumor-bearing animals served as additional groups of study and control animals. Adult sarcoma-bearing mice showed an increase in plasma levels of GH early following tumor implantation. GH levels increased further with tumor progression. The anorexia and the state of malnutrition in sarcoma-bearing mice were the major factors behind increased GH levels. Muscle wasting and body composition in the tumor-bearing host were not improved by GH treatment at doses that increased growth rate in normal growing mice with intact pituitaries or partially normalized growth rate in hypophysectomized rats. Exogenous GH supported tumor growth and host body growth to the same extent in hypophysectomized rats. Exogenous GH in excess of endogenous GH did not stimulate tumor growth further. It is suggested that increased GH production in a tumor-bearing host acts in concert with other hormones to stimulate endogenous substrate mobilization and in tumor-bearing animals to prevent substrate deficiency and hypoglycemia. On the basis of this conclusion, it is unlikely that GH supplementation to a freely eating tumor-bearing host will support replenishment of host tissues.
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PMID:Growth hormone and experimental cancer cachexia. 348 Mar 85

Peritoneal macrophages from mice bearing a transplantable methylcholanthrene-induced sarcoma produced progressively less IL 1 as tumor burden increased. The loss of activity was not explained by the production of any inhibitor of the mouse thymocyte comitogen bioassay. Immune precipitation with a polyclonal antibody confirmed the decline in IL 1 appearance. Although tumor-bearing animals lost approximately 17% of their carcass mass, the reduced production of IL 1 was not satisfactorily explained by coexistent malnutrition, since similarly depleted non-tumor-bearing mice were capable of producing IL 1. In addition to an altered IL 1 production by macrophages of tumor-bearing mice, SDS-polyacrylamide gel electrophoresis and autoradiography revealed that the pattern of secretory protein synthesis from LPS-stimulated and unstimulated peritoneal macrophages differed between tumor-bearing and control animals. Administration of LPS to tumor-bearing mice early after tumor transplantation resulted in reduced tumor growth and prevented the down-regulation of in vitro IL 1 production by peritoneal macrophages. These findings demonstrate a specific defect in IL 1 production associated with increasing tumor burden. Further studies are required to determine whether this defect in IL 1 synthesis contributes to the increased tumor growth.
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PMID:Down-regulation of interleukin 1 production by macrophages of sarcoma-bearing mice. 349 87

This study evaluated whether altered insulin metabolism is a key factor behind weight loss during sarcoma growth in nongrowing mice (C57BL/6J). Fasted sarcoma-bearing mice had decreased blood glucose concentrations but unchanged levels of insulin, compared with those in pair-weighed and freely fed controls. During refeeding, insulin levels were inappropriately low for the degree of glycemia in sarcoma-bearing mice compared with those of pair-weighed and freely fed controls. Injections ip of glucose to tumor-bearing animals resulted in insulin levels comparable to postabsorptive values in healthy control animals, indicating that hypoinsulinemia in freely eating tumor-bearing animals was due to a reduced glycemic sensitivity for pancreatic insulin release. Insulin supplementation at doses [4 IU/100 g (body wt)] that increase body fat in normal animals could not protect the tumor-bearing host from progressive loss of body fat or lean tissues. Exogenous insulin in excess of endogenous insulin production did not stimulate tumor growth. Nitrogen and RNA-DNA content were significantly decreased in the quadriceps muscle of tumor-bearing mice. This reduction was independent of altered insulin levels and could not be prevented by exogenous insulin. The depressed capacity of protein synthesis in extensor digitorum longus (EDL) muscle could be entirely attributed to the state of malnutrition in tumor-bearing animals. The sensitivity and responsiveness of protein synthesis in EDL muscles to insulin were normal in tumor-bearing mice, regardless of whether exogenous insulin exerted its effect in vivo or in vitro. This study confirms insulin resistance for glucose metabolism in an experimental sarcoma animal model. Such changes are concluded to be secondary to anorexia and necessary to counteract hypoglycemia. In non-growing sarcoma-bearing mice, malnutrition and anorexia account entirely for depressed muscle protein synthesis, which is not explained by insulin resistance at the translational level. Insulin metabolism is not a key factor behind progression of wasting in sarcoma-bearing mice, but anorexia is.
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PMID:Role of insulin in development of cancer cachexia in nongrowing sarcoma-bearing mice: special reference to muscle wasting. 355 91

Leucine and whole body protein metabolism were quantitated in 26 human subjects (6 sarcoma patients, 20 age-matched normal controls) using a primed, continuous infusion of [13C]leucine. Plasma samples were analyzed every 15 min for enrichment of [13C]leucine. Plateau enrichment levels were then used to calculate whole-body protein turnover, synthesis, and breakdown rates. Exhaled gas samples were analyzed every 15 min for enrichment of 13CO2, and plateau enrichment levels (as well as CO2 production rates) were used to calculate leucine oxidation rates. Fasting plasma amino acid levels, serum albumin, and total protein levels were also determined. The 6 patients were otherwise healthy but had a large, localized high-grade sarcoma which had not been previously treated. No patient had weight loss. Amino acid, albumin, and total protein levels were equivalent in patients and controls. Whole-body protein turnover rates were significantly greater in sarcoma patients than age-matched controls (15%). Increased protein turnover rates resulted in increased whole-body protein synthesis and breakdown rates in sarcoma patients compared to controls. Leucine oxidation rates were not different in the 2 groups. The results suggest that in humans with high-grade sarcomas leucine metabolic abnormalities are specific to tumor growth and not malnutrition because abnormalities of turnover, synthesis, and breakdown occur prior to any weight loss or measurable change in blood amino acid or protein level.
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PMID:Altered leucine metabolism in noncachectic sarcoma patients. 362 Nov 73

Although patients with solid tumors do not suffer similar rates of infections as patients with hematologic malignancies, several predisposing factors may influence their outcome. These factors include tumor growth, malnutrition, alteration of anatomic barriers, and side effects of various therapeutic modalities. Specific nursing interventions for the prevention of infections are described.
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PMID:Infections in patients with solid tumors. 384 19


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