Lung colony formation: a selective cloning process for lung-colony-forming ability.
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Lymphoid cells stimulated by soluble tumour antigens in the MCA-induced murine fibrosarcoma system have been identified by subclass and protective capacity in adoptive syngeneic hosts. Lymph-node or spleen cells taken at weekly intervals after inoculation of syngeneic chemically induced fibrosarcomas were enriched by 3 methods in T, B, and "null" cell subclasses, and assayed for proliferative kinetics in response to soluble membrane antigens. The stimulated subpopulations were found to be heterogeneous, their composition varying with time and tumour burden. Initial proliferative responses after tumour inoculation were limited to the T-enriched subpopulation. Later during tumour growth, T, B and null cell fractions were vigorously and equally stimulated by tumour antigen. The ability of the same T, B or null-cell subpopulations to inhibit tumour growth was measured in adoptive hosts by a modified Winn assay. Only the T-cell subpopulation responding to tumour antigen in vitro effectively and consistently retarded tumour growth in vivo. In contrast to the shared specificities on syngeneic tumours identified by the proliferative assay, tumour-growth inhibition was limited to the specific tumour borne by the cell donor.
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Weanling Fischer 344 rats received a single intraperitoneal injection of a 1000-fold concentrated preparation of endogenous nontransforming rat retrovirus. Ten days later, the rats were each given a single subcutaneous injection of 3-methylcholanthrene. The rats inoculated with the endogenous rat retrovirus were significantly protected against the development of cancer, whereas uninoculated rats and rats given one of several murine retroviruses or baboon retrovirus were not protected.
In the BPV1.69 line of transgenic mice, the bovine papillomavirus type 1 genome elicits both benign dermal fibroblastic proliferation (fibromatoses) and malignant fibrosarcomas. Because these lesions arise only with time, nonviral factors appear to be involved. We have karyotyped several primary tumors as well as a series of low-passage cell lines derived both from fibromatoses and from fibrosarcomas. The fibrosarcomas, but not the preneoplastic fibromatoses, show consistent abnormalities of one or both of two chromosomes, chromosome 8 (trisomy or duplication) and chromosome 14 (monosomy or translocation). The chromosomal abnormalities are not a direct consequence of the viral integration, which we have mapped to chromosome 15 by in situ hybridization. These results suggest that transgenic mice can be used to study the role(s) of cytogenetic changes in tumorigenesis and may direct the search for genes involved in tumor progression.
Progressive growth of the P815 mastocytoma in semisyngeneic mice evokes the generation of a T cell-mediated mechanism of immunosuppression that inhibits the capacity of passively transferred, tumor-sensitized T cells from regressing this tumor in recipient mice. This conclusion is based on two findings: (a) that it is possible to demonstrate adoptive T cell-mediated regression of established tumors, but only if the tumors are growing in T cell-deficient recipients, and (b) that adoptive T cell-mediated regression of tumors in these recipients can be inhibited by the infusion of splenic T cells from T cell-intact, tumor-bearing donors. The results of additional experiments designed to measure the effect of decreasing the number of suppressor cells and the time that they are infused, relative immune cells, indicate that the function of suppressor cells in this model is to inhibit the replication of passively transferred immune T cells. The results obtained with the P815 mastocytoma are similar to those obtained previously with a chemically induced fibrosarcoma. They show, in addition, that passively transferred immune cells are capable of destroying already seeded metastases in T cell-deficient recipients.
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Sternal hyaline cartilages of Syrian hamsters were dissociated with collagenase and culured. Primary monolayer cultures of the dissociated cells were morphologically homogeneous. Secondary cultures of the chondrocytes were treated with 1 x 10(-6) or 2 x 10(-6) M 4-nitroquinoline-1-oxide (4NQO) for 3 hours or with 5 or 10 microgram 3-methylcholanthrene (MCA)/ml for 3 days. Cultured chondrocytes transformed morphologically 29-51 days after 4NQO treatment and 41-61 days after MCA treatment and began to grow continuously in vitro. Cultures of transformed cells, like transformed fibroblasts. Untreated cells and cells treated with dimethyl sulfoxide did not transform within at least 110 days after inoculation. Among the transformed cells, one near-diploid cell line preserved the distinct phenotypic expression of chondrocytes, whereas heteroploid cell lines lost their differentiated features. The near-diploid cell line produced nodules in the cheek pouches of hamsters within a week, by the nodules regressed later. They showed the chondrogenic properties of the original cells and stained metachromatically with toluidine blue. Heteroploid cell lines formed progressive tumors with few chondrogenic features; these tumors were diagnosed as fibrosarcomas.
The densities of viable EMT6 cells grown in vitro as monolayer exponential and plateau-phase cells or as multicell spheroids or in vivo as a solid tumor in BALB/c mice were determined with the use of isopyknic centrifugation in linear Ficoll gradients. Exponential cells banded at a density of 1.069 g/ml, whereas plateau-phase cells appeared at 1.073 g/ml. Cells grown as spheroids were more dense than the monolayer cells and were recovered mainly at 1.081. Solid-tumor cells, separated under the same conditions, banded at 1.080. Narrowing the range of the Ficoll gradient failed to resolve more than one band of cells in the solid-tumor separation. This provides evidence that the density of cells obtained from the spheroids is greater than that of the monolayer cells but agrees well with the density of the solid-tumor cells. Ficoll was demonstrated to be nontoxic to the cells, and plating efficiency assays showed similar cell viabilities between noncentrifuged and centrifuged cells. The plating efficiency of the peak fraction of exponential cells after centrifugation was 68%, and that of plateau-phase cells was 50%. Corresponding figures for the multicell spheroid and solid-tumor cells were 62 and 28%, respectively. The recovery of cells after centrifugation in the Ficoll gradients ranged from 62 to 83%. The effects of cell load and centrifugation time on the density distributions of the EMT6 cells were also investigated.
A marked and progressive decrease in the activity of the histamine forming enzyme, histidine decarboxylase (HDC), of tumors was found to be associated with the progressive growth of SV-40 virus induced and transplanted syngeneic non-metastasizing fibrosarcomas in inbred LSH Syrian hamsters. Histamine forming enzyme activity was highest in the smallest tumors (p < .005) and in the tumors with the slowest growth rate (p < .005, r - 0.84). Tumor histamine forming enzyme activity was highest for each interval of animal exposure to inoculated tumor cells in those animals which had limited their tumor growth to the smallest tumor size. These findings suggested a local anti-inflammatory effect of progressive tumor growth. Induced local inflammation by repeated intratumor injections of bradykinin markedly elevated tumor histamine forming enzyme activity above expected levels for tumors of the same size in a small group of individual animals which were sampled at random from a larger group of animals which were being studied for the tumor growth kinetics effects of repeated intralesional injections of bradykinin. Tumor histamine forming enzyme activity was highest in those animals which were managed by the frequency of injection and dose schedules which were found in the tumor growth kinetics study to be most effective in limiting tumor growth. These findings suggested that the observed anti-inflammatory effects of progressive tumor growth may be reversed by locally induced inflammation at the tumor site with beneficial effects on tumor growth.
Ameloblastic fibrosarcoma (AFS) is a rare malignant tumor of the jaw. The malignant mesenchymal component of AFS has been described as 'fibroblast-like', although little is known about the immunophenotype, except for vimentin expression. Here, we present a case of AFS in a 62-year-old woman. The mesenchymal component displayed the features of either dermatofibrosarcoma protuberans or fibrosarcoma, and was positive for CD34. This is the first reported case of CD34 expressing AFS in the maxilla.
The genetic control of hybrid resistance to BALB/c fibrosarcoma Meth-A was investigated. A Meth-A tumour grew slower in (BALB/c x C57BL/6)F1 and reciprocal hybrid mice than in syngeneic BALB/c mice and was also found to grow slower in females than in males. Significant F1 resistance was demonstrated after both subcutaneous and intraperitoneal injection of tumour cells. However, (BALB/c x DBA/2)F1 mice did not show any significant resistance to Meth-A. In H-2 linkage studies of [BALB/c x (BALB/c x C57BL/6)] backcross mice, no statistically significant differences in the resistance of H-2 heterozygotes and homozygotes to Meth-A were observed. These results indicated that F1 hybrid resistance to Meth-A was controlled by non-H-2-linked resistance factor(s). No linkage was observed between resistance to Meth-A and coat colour c- and b-loci.
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Characterization of transport kinetics involved in tissue folate supply has been limited by the inability to accurately measure the uptake and metabolism of folate by rapidly proliferating tissues. The present report describes a new animal model that uses subcutaneous fibrosarcoma implants as a target tissue for studies of folate supply. The fibrosarcoma grows rapidly as a well-encapsulated, nonmetastasizing nodule(s) and does not disrupt the animal's normal growth and nutrition. Moreover, the tumor nodules avidly take up labeled folate and can be removed easily by local excision for measurements of uptake and intracellular metabolism of folate.
The role of hyperthermia during regional alkylating agent chemotherapy is controversial. The aim of this study was to determine the exact contribution of hyperthermia to tumor response during isolated limb infusion with l-phenylalanine mustard. Rats bearing rodent fibrosarcoma on the hindlimb underwent isolated limb infusion with saline, saline plus heat, l-phenylalanine mustard, l-phenylalanine mustard under conditions of normothermia, or l-phenylalanine mustard plus hyperthermia. Heat was administered locally using an in-line hot water circulation loop. Treatment with l-phenylalanine mustard at a concentration of 15 or 50 micrograms/mL was ineffective at producing tumor growth delay (P = 0.24 and 0.41, respectively). Furthermore, thermal enhancement of l-phenylalanine mustard activity was not seen at 15 micrograms/mL. However, administration of high-dose l-phenylalanine mustard, 50 micrograms/mL, with increasing amounts of heat yielded increasing tumor growth delay, increased regressions, and decreased proliferative index. Although l-phenylalanine mustard infusion under normothermia yielded a tumor growth delay of 7.1 days, combination l-phenylalanine mustard + hyperthermia treatment produced tumor growth delay of 27.0 days (P < 0.01; with two of five animals showing a complete response). Four hours after isolated limb infusion, 50.9% of cells in tumor treated with l-phenylalanine mustard + hyperthermia experienced apoptosis, whereas only 18.1, 16, and 4.4% of cells underwent apoptosis after treatment with l-phenylalanine mustard, saline + hyperthermia, or saline. The mean concentration of l-phenylalanine mustard within tumor relative to perfusate following isolated limb infusion was found to be similar among all groups at 0.023, 0.025, and 0.032 in animals undergoing isolated limb infusion with l-phenylalanine mustard, l-phenylalanine mustard + normothermia, and l-phenylalanine mustard + hyperthermia, respectively. These data indicate a synergistic cytotoxic effect of l-phenylalanine mustard + hyperthermia in isolated limb infusion, which is not attributable to enhanced tumor drug uptake.
The objective of the present study was to investigate the efficacy of (111)In-DTPA-octreotide (OC) for in vivo scintigraphic imaging of these relatively uncommon tumors. Thirteen patients (9 males, 4 females, mean age 59 years) with known sarcomatous lesions were studied. All patients had known lesions as demonstrated by previous investigation with other modalities, e.g. CAT, MRI. Following intravenous injection of 10 microg of OC labeled with 2.8-4.2 mCi (111)In, planar imaging was done at 6 +/- 1 and 22 +/- 2 h, respectively. Histologic verification was obtained in all cases, either from fine needle aspiration or from surgically removed tissue. Positive imaging was observed in 12/13 cases (92.3%). One scan was false-negative (7.7%). Occult lesions were demonstrated in two patients. The histologic typing and the scintigraphy results were: fibrosarcoma (1+/1), embryonic rhabdomyosarcoma (1+/1), leiomyosarcomas (3+/3), liposarcomas (2+/2), uterine sarcomas (2+/2), HIV (-) Kaposi sarcoma (1+/1), osteosarcoma (1+/1), chondrosarcoma (1-/1) and neurogenous sarcoma (1+/1). OC appears to have properties that lead to a new indication for its use. Other possible applications relate to the therapeutic use of octreotide either unlabeled or labeled with a beta-emitting radionuclide, as well as its use in radioimmunoguided surgery. Regarding the latter, our preliminary results are encouraging.
A right parietal lobe metastasis of a fibrosarcoma originating in the left atrium of the heart was resected twice in a 33-year-old man. Light microscopy showed lightly packed, pleomorphic spindle cells with abundant collagen production and an alcian blue-positive matrix. Electron microscopy confirmed the fibroblastic character of these cells. Review of the literature reveals one other cardiac fibrosarcoma metastatic to the brain. The case presented is the first reported example of successful surgical resection of this unusual metastatic sarcoma. Although he succumbed to metastatic disease, the patient remained neurologically intact until the time of death.