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

At various stages during the progressive growth of a transplanted sarcoma in BALB/c mice, the delayed hypersensitivity response to tumor antigen was determined using the food-pad swelling test (FPS) and the leukocyte migration inhibition assay (LMI). A close correlation was observed between the in vivo and in vitro assays. "Early" recognition of tumor antigen was detected 24 h after tumor inoculation by both techniques and this positive response was maintained until day 15. As the tumor grew larger, the delayed hypersensitivity response in vivo vanished, while the delayed hypersensitivity response in vitro disappeared about 3 days later. This suppression or "eclipse" of the anti-tumor cellular immune response was specific for the type of tumor used, and could be reversed in vitro by means of a low pH treatment of lymphoid cells.
Int J Cancer 1977 Sep 15
PMID:Delayed hypersensitivity in tumor-bearing mice. In vitro activation of "eclipsed" spleen cells. 2 Apr 7

We tested the cyclophosphamide effects against the growth of adenovirus-transformed cells and the subsequent tumor development in the syngeneic host. Cyclophosphamide did not show any effect on the tumor evolution when injected 24 and 6 hours before cell implantation. Cyclophosphamide injected 24 or 39 hours after cell implantation prevented or retarded the tumor growth. In mice bearing palpable tumors, it induced their complete regression in 85,7% of the animals, but did not effect the development of the homograft immunity.
Boll Ist Sieroter Milan 1977 Sep
PMID:Effect of cyclophosphamide on syngeneic transplantation of adenovirus 12-transformed tumor cells in C3H/he mice. 2 Sep 3

gamma-Glutamyl transpeptidase activity was detected in rat ascites tumor cells (LY-5) suspended in Hanks' balanced saline solution using L-gamma-glutamyl-p-nitroanilide as a substrate. Whole-cell suspension of the tumor cells exhibited full activity of the enzyme without detectable cell disruption under the conditions examined. Various amino acids, transported through specific membrane carriers, did not affect the accessibility of substrate for the enzyme. An inhibitor of sodium-dependent transport systems of amino acids caused no significant change in the rate of enzyme catalysis. Like glutathione or S-methylglutathione, S-acetyldextran (mol. wt 215000) derivative of glutathione, which is believed to be unable to penetrate into intact cells, caused marked inhibition of the rate of p-nitroaniline release from the synthetic substrate by the tumor cells. These data indicated that the active site of the enzyme faced to the outer surface of the cells. gamma-Glutamyl transpeptidase of the tumor cells was successfully affinity-labeled by 6-diazo-5-oxo-L-norleucine, a glutamine analog, without causing detectable change in the viability of the cells under the conditions examined. The rate of transport of alanine, leucine, glycine and glutamine into cells was not affected by the inactivation of this enzyme with the affinity label. Thus, the activity of gamma-glutamyl transpeptidase located on the outer surface of tumor cell membrane does not seem to be requisite for the transport process of amino acids.
Eur J Biochem 1977 Sep
PMID:gamma-Glutamyl transpeptidase in rat ascites tumor cell LY-5. Lack of functional correlation of its catalytic activity with the amino acid transport. 2 Oct 85

The pH profile in the intercapillary region of tumor tissue is calculated for normal (Case I) and enhanced glucose concentration in blood (Case II) which was increased by a factor of 4 for an extended period of time. The statement used, which takes into account the reduced lactic acid formation in the unsaturated region of cancer cell glycolysis, and the resulting solution of the lactic acid diffusion field equation are given. For Case II (conditions of cancer multistep therapy) and a capillary radius of 4 micrometer this yields the following pH values: Wall at venous end of the capillary 6.7 (or 6.5); at R greater than 12 micrometer, i.e. still in the vicinity of the capillary less than 6.3: at R approximately 60 micrometer a minimum of 5.9. This rather good pH homogeneity is the prerequisite that all lytic actions and activation mechanism induced by a temporary extreme hyperacidification of the tumor tissue can take place in the major portion of the intercapillary region with a strength of adequate uniformity. Conclusions were drawn from these results with respect to the further planning of cancer therapy. This refers to the utilization of processes serving to increase primary damage to tumor tissue through body defense mechanisms, inhibition of cell proliferation as well as the applicability of new anticancer drugs (CMT Selectines) that are rendered active only in strongly hyperacidified foci of cancer. Moreover, this includes the possible use for increasing the secondary damage to tumor tissue by way of the lysosomal cytolysis, by drastic decrease of microcirculation and the damage of the capillaries in tumor tissue.
Res Exp Med (Berl) 1977 Sep 30
PMID:[Calculation of the pH profile in the intercapillary regions of tumour tissues before and after long-term glucose infusion into the blood stream (author's transl)]. 2 14

The activities of gamma-glutamyl transpeptidase (gamma-GTP), alkaline phosphatase (A-p), and leucine aminopeptidase (LAP) were examined in 18 cases of hepatomas. The activity of gamma-GTP was most remarkable in the hepatoma consisting of small to medium-sized tumor cells showing the least atypism. The enzyme activity found in the type composed of large tumor cells resembled that of normal liver and was considered to be the most mature form of the neoplasm. This enzyme was not found in the immature type composed of small typical tumor cells. A-P activity was seen in only a few cases of hepatoma; conspicuous in one case showing immature features and sporadically in one case with florid histological pattern. The activity of this enzyme could not be confirmed in the type demonstrating marked gamma-GTP activity. LAP activity was noted in the majority of cases, especially marked in the medium-sized tumor cells, but there was hardly any connection between this enzyme and histological type. In general, the cases demonstrating positive gamma-GTP activity tended to show LAP activity. Although the activity of gamma-GTP and that of A-p usually showed an inverse relation, all three enzymes demonstrated almost equal activity in the type showing a florid histological pattern.
Acta Pathol Jpn 1977 Sep
PMID:Enzyme histochemical study on hepatoma--the relation between enzyme activity and histological type. 2 15

Carbamylcholine, acting via a pharmacologically specific receptor, had the ability to activate effector populations of spleen cells from female BALB/cfC3H and BALB/c mice; those cell populations were then significantly reactive in vitro against syngeneic tumor target cells but were only minimally reactive to normal syngeneic target tissues. The induced reactivity was inhibited by the muscarinic cholinergic antagonists atropine, scopolamine, and isopropamide, but not by the nicotinic antagonist d-tubocurare, and it appeared to involve both T-cell and non-T-cell effectors.
J Natl Cancer Inst 1978 Sep
PMID:Muscarinic cholinergic activation of mouse spleen cells cytotoxic to tumor cells in vitro. 2 33

A retrospective review of 20 cases of testicular neoplasia in cryptorchid patients is presented. These cases serve to emphasize the need for more effective diagnosis and management of the undescended testis. The various clinical presentations, diagnostic modalities, prognostic indicators, and types of management are reviewed. Due to its inaccessibility and array of clinical presentations, the intraabdominal testies tumor continues to be a diagnostic challenge. Strict attention to diagnostic cues and adherence to the management practices presented here would hopefully result in an overall decrease in testis tumors in the post-pubertal male.
J Natl Med Assoc 1978 Sep
PMID:Cryptorchidism and testicular neoplasia. 2 70

We have established a clonal cell line, PC-G2, from an experimentally induced rat pheochromocytoma. Administration of nerve growth factor to PC-G2 causes a 4- to 8-fold induction in the specific activity of tyrosine hydroxylase [tyrosine 3-monooxygenase; L-tyrosine,tetrahydropteridine:oxygen oxidoreductase(3-hydroxylating); EC 1.14.16.2]. The response is elicited in a dose-dependent fashion, at concentrations above 0.1 microgram/ml. Antiserum to nerve growth factor inhibited the induction of tyrosine hydroxylase. Dexamethasone enhances the nerve growth factor-mediated elevation of tyrosine hydroxylase. After 3--4 days of exposure to nerve growth factor the maximal induction of tyrosine hydroxylase is seen, although a significant increase can be observed after 24 hr. In contrast to the PC-12 cell line (derived from the same tumor), in which neurite outgrowth occurs in response to nerve growth factor, there is no morphological change or alteration in growth rate of PC-G2 cells after exposure to nerve growth factor.
Proc Natl Acad Sci U S A 1978 Sep
PMID:Nerve growth factor-mediated induction of tyrosine hydroxylase in a clonal pheochromocytoma cell line. 3 87

Some years will have to pass, until there will be evidence, if application of leaser beam in surgery of Breastcancer, Melanomas or Basaliomas was justified and whether it is possible or not to interrupt or reduce intraoperative tumor cellspread. As an increasing number of surgeons have started to use laser rays in these illnesses, result of laser surgery and those of traditional methods could be compared in a couple of years. Possibly other indications will be outlined in general surgery for the use of laser beside those we have been working out. It may happen that surgeons working with laser beam might bring the method into discredit putting indication not rigorous enough. I should like to remind everybody who starts working with laser rays, to do so with greatest possible care. Collaboration with a technician is recommended. Periodic he should control the machine and handle arising technical problems.
Aktuelle Gerontol 1978 Sep
PMID:[Application of laser rays in surgery (author's transl)]. 3 Mar 26

Combinations of carcinoembryonic antigen (CEA), gamma glutamyl transpeptidase (GGT), pregnancy-associated macroglobulin (PAM) and placenta-like alkaline phosphatase (PLAP) were studied in groups of patients with ovarian and cervical cancer. In ovarian cancer, only CEA and PLAP levels appeared to reflect tumor burden and were complementary in detecting active disease. In cervical cancer, CEA and GGT reflected tumor burden, while PLAP showed just the reverse--the highest degree of positivity being present in minimal disease. PLAP positivity was even more pronounced in patients with cervical dysplasia and carcinoma in situ while CEA and GGT were negative. The data indicate that the use of marker combinations can improve our capacity to detect minimal disease and provide information regarding tumor biology that may not be available by studying individual markers or by other means. It remains to be determined whether the use of tumor markers can influence existing therapy sufficiently to alter the outcome in cancers which are notoriously difficult to treat.
Cancer 1978 Sep
PMID:Carcinoembryonic antigen (CEA) and other tumor markers in ovarian and cervical cancer. 3 May 36


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>