A procedure is described for the selection of glucose uptake mutants based upon radiation suicide of Chinese hamster fibroblasts by 2-deoxy[3H]glucose. In one of these mutants, DS 7, the ability to transport either 2-deoxyglucose or 3-O-methylglucose was decreased to one-fifth to one-fourth. Besides this defect, DS 7 produces l/,4th the lactic acid produced by the parent when grown on 5 mM glucose. This block in aerobic glycolysis is due to a mutation that affects the expression of the phosphoglucose isomerase gene because no isomerase activity is detected in cell extracts of DS 7. This glycolytic block makes that cell line dependent exclusively on respiration for its energy requirement. Consequently, DS 7 survives well after removal of glucose but dies quickly in the presence of oligomycin. The parental line 0 23 (subclone of CCI 39) grows at low serum concentration, is anchorage-independent, and is tumorigenic in nude mice. The derived glycolytic mutant DS 7 has retained both the in vitro transformed phenotype (low serum dependence and loss of anchorage dependence) and the tumor-forming capability. The tumor cells derived from the injection of DS 7 cells have kept the original glycolytic defect. This finding suggests that the transformed properties (high hexose transport and aerobic glycolysis) that can be uncoupled from abnormal growth control are not necessary for the expression of the malignant phenotype in fibroblasts.So far, among the various properties that accompany viral or spontaneous transformation (for review, see refs. 1-4), it has been difficult to assign to any particular transformed property a primary role in the establishment and maintenance of the abnormal growth control. A set of surface and membrane changes-including low adhesion to substratum, rounded shape, increased agglutinability by plant lectins, altered cell locomotion, decreased cell alignment, and loss of microfilament bundles-has been dissociated from the mechanism that alters the control of division (5-9).Increases in hexose transport and in aerobic glycolysis are two other characteristics that one finds closely linked to transformation and increased proliferation in cells (10)(11)(12)(13)(14) The publication costs of this article were defrayed in part by page charge payment. This article must therefore be hereby marked "advertisement" in accordance with 18 U. S. C. §1734 solely to indicate this fact.

Summary.-The growth of a 3-methylcholanthrene-induced fibrosarcoma of C3H mice was inhibited by aspirin and indomethacin. While the tumour contained relatively high concentrations of PGE2-like material, that were markedly diminished by indomethacin treatment, our results did not confirm the recently proposed hypothesis that the anti-tumour effect arises from a restoration of depressed immune function. For example, mice that had completely eliminated their tumours under indomethacin administration were not immune to rechallenge. The tumour-bearing animals were not non-specifically immunodepressed, as their splenic PFC responses against SRBC were enhanced. However, while indomethacin augmented the PFC response in normal mice, this adjuvant effect was depressed in tumour-bearing animals. The spleen-cell PHA responses of tumour bearers were severely depressed, and such cells suppressed the PHA response of normal cells. Only after prolonged indomethacin treatment did animals (with comparable tumour burdens) show weak PHA responses and somewhat diminished suppressive activity.Possible alternative mechanisms, such as direct cytotoxicity, or inhibition of inflammation, phosphodiesterase activity, blood coagulation or calcium availability were not implicated (nor definitively excluded) in the anti-tumour effect.

Summary.-C3H and C57 BL/6 mice carrying methylcholanthrene-induced fibrosarcomas were injected i.p. daily with histamine, metiamide (anti-histamine type-2 receptor), histamine + metiamide, mepyramine (anti-histamine type-i receptor), serotonin and methysergide (anti-serotonin). Inhibition of tumour growth and lengthened survival were observed with histamine and histamine+ metiamide. The best results (both on tumour growth and survival) were obtained with serotonin. Survival was increased by metiamide and decreased by mepyramine and methysergide. In histamine-treated and in serotonin-treated mice, histological studies of the tumours showed large and numerous foci of haemorrhagic necrosis.Stimulation of histamine type-I or serotonin receptors and inhibition of histamine type-2 receptors play a beneficial role in the host's defence against tumours.

When an extracellular dye, Lissamine green, or 51Cr-labeled spleen cells were injected iv into C3H mice bearing small, partially necrotic 3-methylcholanthrene-induced transplantable fibrosarcomas (McC3), the tumor content of these circulating elements per unit weight was substantially lower than that of other selected organs. The level of these blood-borne materials was, however, significantly augmented by the intratumor induction of passive local anaphylaxis (PLA). The PLA-induced augmentation was inhibited by administration of the histamine and serotonin antagonist cyproheptadine; comparable increases were also induced by the intratumor injection of a histamine and serotonin mixture or BCG. The weekly intratumor induction of PLA in McC3 tumors resulted in the complete regression of a significant number of the tumors, and this therapeutic effect was eliminated by cyproheptadine treatment. The intratumor injection of BCG induced the regression of approximately 50% of injected tumors, and the combination of this immunostimulant treatment with the generation of PLA was more therapeutically effective than either treatment alone. PLA in the vicinity of solid tumors may, by increasing vascular permeability, potentiate antitumor effector mechanisms, particularly when these are BCG-stimulated. Despite this demonstration of a possible role of anaphylactic reactions in tumor immunity, no definitive evidence was found that active reagin-mediated local anaphylaxis occurred in C3H mice bearing the McC3 tumor, whether or not they were treated with immunostimulants.

In two parallel studies, bitches with mammary tumour received single intralesional injections of BCG (1 mg: 10(7) living bacteria) and Corybacterium parvum (10(9) killed bacteria) (53 bitches) or C. parvum alone (129 bitches) at the same dosage. Control groups received injections, following the same protocol, of 1 ml BCG suspension medium diluted in saline in the first study (51 bitches) or no injections at all (120 bitches in the second study). A block dissection, including mammary tumours, adjacent mammary glands, and regional lymph nodes, was performed 2 weeks later in all animals. On the basis of histologically confirmed malignant tumours, 48 bitches (25 treated by-immunotherapy and 23 controls) in the first study and 67 bitches (30 treated by immunotherapy and 37 controls) in the second study remained for postsurgical follow-up. The clinical tolerance of the treatment was generally good. No significant differences were found in cumulative survival rates between treated and control group in either studies.