Induction of tumors in hamsters by rat Rous sarcoma RBI, producing chick sarcoma virus. I. Continuous production of virus oncogenic for chicks by hamster sarcoma cells.
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Animals↗
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[Study of the clinically so-called infectious venereal sarcoma of dogs. III. Chromosomes of free sarcoma cell in the secretion of venereal sarcoma of dogs and fluid infection among dogs by free tumor cells].
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Animals↗
[A SARCOMA OF THE PERIOSTEUM: JUXTACORTICAL COMPLEX OSTEOGENIC SARCOMA, SARCOMA OF ATTENUATED MALIGNANCY].
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Bone Neoplasms↗
Studies on Rous sarcoma virus in mice. I. Establishment of an ascites sarcoma induced by the Schmidt-Ruppin strain of Rous sarcoma virus in C3H-He mouse.
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Animals↗
Kaposi's sarcoma-associated herpesvirus-like DNA sequences (KSHV/HHV-8) in oral AIDS-Kaposi's sarcoma: a PCR and clinicopathologic study.
Recently, a new human herpesvirus (KSHV/HHV-8) has been identified in classic, transplant, endemic, and AIDS Kaposi's sarcoma that may be involved in the pathogenesis of Kaposi's sarcoma. The purpose of this study was to evaluate oral AIDS-Kaposi's sarcoma for detection of KSHV/HHV-8 DNA. DNA extracted from 54 oral AIDS-Kaposi's sarcoma lesions (47 initial, 7 postvinblastine treated), 5 non-Kaposi's sarcoma HIV-positive lesions, and 3 non-Kaposi's sarcoma HIV-negative lesions was evaluated by polymerase chain reaction (KS330(233bp)amplicon) for KSHV/HHV-8. The AIDS-Kaposi's sarcoma study population consisted of 52 patients (51:1, men:woman; 92% men having sex with men, 8% heterosexual; mean age, 38 years; mean, CD4 59/mm3) Opportunistic infections occurred in 88% (candidiasis, 65%; Pneumocystis carinii pneumonia, 31%; nonoral Kaposi's sarcoma, 25%; mycobacterium avium-intracellulare (MAI), 16%; cytomegalovirus, 14%; herpes simplex virus, 14%). Sexually transmitted diseases occurred in 73% (gonorrhea, 37%; syphilis, 23%; condyloma, 22%; HSV, 16%). Most frequent lesion sites were palate (74%) and gingiva (17%). Most common lesion types were purple nodular (48%) and macular (42%). Histopathologic subtypes were nodular (71%), plaque (27%), and patch (2%). Polymerase chain reaction analysis detected KSHV/HHV-8 DNA in 53 of 54 AIDS-Kaposi's sarcoma lesions (47 of 47 initial, 6 of 7 postvinblastine treatment). KSHV/HHV-8 DNA was not detected in non-Kaposi's sarcoma lesions in HIV-positive or HIV-negative persons. KSHV/HHV-8 DNA sequence is present in a high proportion of oral AIDS-Kaposi's sarcoma lesions. Whether KSHV/HHV-8 is an etiologic agent or a cofactor in the development of this vascular neoplasm is uncertain and remains to be proven. Polymerase chain reaction analysis for KSHV/HHV-8 DNA sequence detection may be helpful in identifying Kaposi's sarcoma in early vascular proliferations, when the characteristic histopathologic features are not present.
AIDS-Related Opportunistic Infections↗
Seroconversion to antibodies against Kaposi's sarcoma-associated herpesvirus-related latent nuclear antigens before the development of Kaposi's sarcoma.
BACKGROUND: If Kaposi's sarcoma-associated herpesvirus (KSHV) is the cause of Kaposi's sarcoma, serologic evidence of infection should be present in patients before the disease develops. METHODS: Using an immunoblot assay for two latent nuclear antigens of KSHV, we tested serum samples from homosexual male patients with the acquired immunodeficiency syndrome (AIDS) with and without Kaposi's sarcoma (HIV-infected men with hemophilia), HIV-seronegative blood donors, and HIV-seronegative patients with high titers of antibodies against Epstein-Barr virus (EBV). Serial serum samples obtained from patients with Kaposi's sarcoma before the diagnosis of the disease were tested for evidence of seroconversion. RESULTS: Of 40 patients with Kaposi's sarcoma, 32 (80 percent) were positive for antibodies against KSHV antigens by the immunoblot assay, as compared with only 7 of 40 homosexual men (18 percent) without Kaposi's sarcoma immediately before the onset of AIDS. Of 122 blood donors, 22 EBV-infected patients, and 20 HIV-infected men with hemophilia, none were seropositive. When studied by the immunoblot assay over a period of 13 to 103 months, 21 of the 40 patients with Kaposi's sarcoma (52 percent) seroconverted 6 to 75 months before the clinical appearance of Kaposi's sarcoma. The median duration of antibody seropositivity for KSHV-related latent nuclear antigens before the diagnosis of Kaposi's sarcoma was 33 months. CONCLUSIONS: In most patients with kaposi's sarcoma and AIDS, seroconversion to positivity for antibodies against KSHV-related nuclear antigens occurs before the clinical appearance of Kaposi's sarcoma. This supports the hypothesis that Kaposi's sarcoma results from infection with KSHV.
Acquired Immunodeficiency Syndrome↗
Overexpression of bcl-2 protein in synovial sarcoma: a comparative study of other soft tissue spindle cell sarcomas and an additional analysis by fluorescence in situ hybridization.
The expression of bcl-2 protein was analyzed in 19 synovial sarcomas and 29 additional soft tissue spindle cell sarcomas as controls by the immunohistologic staining of paraffin-embedded specimens; 15 of 19 (79%) synovial sarcoma cases were positive, but all other spindle cell sarcomas were negative including 20 leiomyosarcomas, 4 malignant peripheral nerve sheath tumors, and 4 fibrosarcomas. In 4 cases of bcl-2-positive synovial sarcoma (3 biphasic and 1 focally glandular type), bcl-2 protein staining was much stronger in the spindle cells than in the epithelial cells. A fluorescence in situ hybridization (FISH) analysis with centromeric and whole chromosome painting probes for chromosome 18 and X was performed on 7 synovial sarcomas. The six cases of bcl-2-positive synovial sarcoma consisted of five cases with the t(X; 18) and one case with tetrasomy of chromosome 18 and X. It has been speculated that bcl-2 protein expression is caused by the 14; 18 translocation and other abnormalities of chromosome 18. This study thus showed the feasibility of such a correlation between bcl-2 protein expression and the characteristic cytogenetic abnormality in the synovial sarcoma-X; 18 translocation. In addition, bcl-2 protein also appears to be a characteristic marker of synovial sarcoma and is thus considered to be potentially useful in distinguishing synovial sarcoma from other spindle cell sarcomas.
Chromosomes, Human, Pair 18↗
Keratin subsets in spindle cell sarcomas. Keratins are widespread but synovial sarcoma contains a distinctive keratin polypeptide pattern and desmoplakins.
The presence of individual keratin polypeptides and desmoplakins was immunohistochemically studied in 25 spindle cell sarcomas of different types using acetone-fixed frozen sections. Results revealed that keratins 8 and 18 were present in a high number of tumors: 9 of 9 synovial sarcomas, 5 of 7 leiomyosarcomas, 5 of 5 malignant schwannomas, and 1 of 4 undifferentiated spindle cell sarcomas. In addition to keratins 8 and 18, the glandular component of synovial sarcoma showed prominent reactivity with antibodies to keratins 7 and 19. Also the glandular epithelial cells in synovial sarcoma showed desmoplakin immunoreactivity preferentially in a luminal distribution, but desmoplakin was absent in other spindle cell sarcomas. Furthermore keratin 13 was seen focally in 4 of 9 synovial sarcomas. In contrast, keratins 7, 13, and 19 were practically absent in leiomyosarcomas, malignant schwannomas, and undifferentiated spindle cell sarcomas. The widespread presence of keratins 8 and 18 in various spindle cell sarcomas may reflect aberrant keratin expression in mesenchymal cells, previously described in cultured transformed fibroblasts. The presence of keratins 7 and 19 and desmoplakin is highly associated with morphologically observable epithelial differentiation restricted to synovial sarcoma among spindle cell sarcomas.
Cytoskeletal Proteins↗
The immune status of avian sarcoma virus-infected chickens as a determinant of sarcoma growth pattern and viral antigen expression.
Patterns of sarcoma growth were compared in immune-suppressed (cyclophosphamide-treated) vs nonsuppressed avian sarcoma virus-infected chickens. Sarcomas were initially induced in suppressed or nonsuppressed line FP chickens (donors) by wing web inoculation with clone 85, an avian sarcoma virus encoding an envelope glycoprotein that is non-antigenically cross-reactive with endogenous viral glycoprotein. Sarcoma tissue from these donors was then implanted in the wing webs of suppressed or nonsuppressed recipients to compare the effects of immune suppression of donors and of recipients. Sarcoma tissue that had been excised from suppressed donors and implanted in the wing webs of nonsuppressed recipients evidenced a much greater capacity than sarcoma tissue from nonsuppressed donors to yield distal sarcomas localized to visceral organs and to induce expansion by infection-mediated recruitment of new sarcoma cells. In contrast, immune suppression of the recipients of sarcoma tissue from nonsuppressed donors was not significantly enhancing for these effects. The enhancement achieved by immune suppression of the donors correlated with a markedly increased level of virus production and viral antigen expression by the primary (wing web) sarcoma cells from these donors.
Animals↗
Influence of doxorubicin dose intensity on response and outcome for patients with osteogenic sarcoma and Ewing's sarcoma.
The goal of this study was to use dose-intensity analyses of published Ewing's sarcoma and osteogenic sarcoma trials to determine which agents were most closely associated with a favorable response. The percentage of patients with more than 90% tumor necrosis following neoadjuvant chemotherapy was the end point for analysis of osteogenic sarcoma trials, and disease-free survival and percentage of patients with distant-only relapse were the end points for analysis of Ewing's sarcoma trials. The data were analyzed using logistic regression analysis to circumvent the distortion of univariate analysis resulting from the correlation between doxorubicin dose intensity and the dose intensity of other agents. Our analysis suggests that doxorubicin dose intensity is an important determinant of favorable outcome for both Ewing's sarcoma and osteogenic sarcoma and that the dose intensities of other agents do not contribute as significantly to outcome as does doxorubicin dose intensity. Increasing dactinomycin dose intensity was associated with a poorer outcome in treatment of osteogenic sarcoma and Ewing's sarcoma, most likely resulting from regimens with a higher dactinomycin dose intensity having a lower doxorubicin dose intensity. While our analysis of osteogenic sarcoma trials is consistent with significant activity for cisplatin and high-dose methotrexate (and likely ifosfamide), a rank ordering of the efficacy of these agents when given with doxorubicin in multiagent regimens is not possible. Our analysis illustrates the importance of analyzing the contributions of individual agents to combination chemotherapy regimens. In the design of future clinical trials for osteogenic sarcoma and Ewing's sarcoma, careful attention should be given to optimizing doxorubicin dose intensity in regimens to be tested.
Dose-Response Relationship, Drug↗
Molecular diagnosis of sarcomas: chromosomal translocations in sarcomas.
CONTEXT: Sarcomas are rare, numerous in type, and often difficult to definitively classify. Work in the last 2 decades has revealed that a significant subset of sarcomas are associated with specific chromosomal translocations producing chimeric (fusion) genes that play a role in the sarcomas' biology and are helpful in their differential diagnosis. OBJECTIVE: To briefly review the sarcomas associated with specific translocations presenting Ewing sarcoma and synovial sarcoma as archetypes and to further explain how cytogenetic and molecular biologic approaches are being used in the diagnosis of sarcomas. DATA SOURCES: This work is based on a selected review of the relevant medical and scientific literature and our extensive experience with molecular testing in sarcomas. CONCLUSIONS: In addition to, and complementing, the traditional diagnostic methods of examination of hematoxylin-eosin stained slides, immunohistochemistry, and sound clinical-pathologic correlation, additional cytogenetic and molecular biologic methods are being increasingly utilized and relied on in sarcoma pathology. These methods include chromosomal karyotyping, fluorescence in-situ hybridization, spectral karyotyping, and polymerase chain reaction- based methods for demonstrating specific chromosomal translocations and fusion genes. Understanding the basis of these methods and their application is critical to better provide accurate and validated specific diagnoses of sarcomas.
Bone Neoplasms↗
Second malignancies after Ewing's sarcoma: radiation dose-dependency of secondary sarcomas.
BACKGROUND: An excess risk of second malignancies has been reported in survivors of Ewing's sarcoma. We examined a multiinstitutional data base to reevaluate the risk among survivors of Ewing's sarcoma and to identify possible causal factors. METHODS: Information was derived from a data base that included 266 survivors of Ewing's sarcoma. Cumulative incidence rates of second malignancies were calculated. Contributions of clinical features, type and dose of chemotherapy, and cumulative radiation dose to the risk of second malignancies were evaluated. RESULTS: After a median follow-up duration of 9.5 years (range, 3.0 to 30), 16 patients have developed second malignancies, which included 10 sarcomas (five osteosarcomas, three fibrosarcomas, and two malignant fibrous histiocytomas) and six other malignancies (acute myeloblastic leukemia, acute lymphoblastic leukemia, meningioma, bronchioalveolar carcinoma, basal cell carcinoma, and carcinoma-in-situ of the cervix). The median latency to the diagnosis of the second malignancy was 7.6 years (range, 3.5 to 25.7). The estimated cumulative incidence rates at 20 years for any second malignancy and for secondary sarcoma were 9.2% (SD = 2.7%) and 6.5% (SD = 2.4%), respectively. The cumulative incidence rate of secondary sarcoma was radiation dose-dependent (P = .002). No secondary sarcomas developed among patients who had received less than 48 Gy, while the absolute risk of secondary sarcoma was 130 cases per 10,000 person-years of observation among patients who had received > or = 60 Gy. CONCLUSION: The overall risk of second malignancies after Ewing's sarcomas is similar to that associated with treatment for other childhood cancers. The radiation dose-dependency of secondary sarcomas justifies modification in therapy to reduce radiation doses.
Adolescent↗
Local recurrence of soft tissue sarcoma. A Scandinavian Sarcoma Group Project.
The aim of this project was to investigate the diagnosis, treatment and consequences of local recurrence of soft tissue sarcoma (STS). It is based on patients reported to the Karolinska Hospital Sarcoma Register and the Scandinavian Sarcoma Group Register. Demographic and treatment data, based on 1613 adult patients reported to the Scandinavian Sarcoma Group Register by sarcoma centers in Norway, Sweden and Finland are presented. They all had STS of the extremities or trunk wall, and were diagnosed between 1986 and 1995. One third of the tumors were subcutaneous and two thirds deep-seated. The median size was 7 (1-35) cm and 75% were high grade. Metastases at presentation were diagnosed in 8% of the patients. Two thirds of the patients were referred to a sarcoma center before surgery. The preoperative morphologic diagnosis was made by fine-needle aspiration cytology in 72%. Among patients with final treatment for primary tumor at a sarcoma center (n = 1331), the surgical margins were wide or better in 76% of subcutaneous lesions, and in 58% of deep-seated lesions. Adjuvant radiotherapy has not generally been considered indicated after wide or compartmental excisions in Scandinavia. Overall, 23% of patients managed by surgery had adjuvant radiotherapy. Among patients with an intralesional or marginal excision, 44% had postoperative radiotherapy. Patients treated outside of sarcoma centers were seldom referred for radiotherapy. The crude local recurrence rate was 225/1331 (17%) among the patients with final treatment for primary tumor at a sarcoma center. The local recurrence rate after local surgery for high-malignant deep-seated STS was 103/391 (26%). The rate was 25/64 (39%) after an intralesional/marginal margin without postoperative radiotherapy versus 28/119 (24%) when radiotherapy was given. Fine-needle aspiration cytology (FNAC) was used to diagnose suspected local recurrences. 95 FNAC were performed in 86 patients from Karolinska Hospital. There were 47 local recurrences, of which 44 were diagnosed correctly by FNAC; one biopsy was inconclusive, and two lesions were incorrectly assessed as benign. 39 patients proved to have benign lesions in the scar examined cytologically on 50 occasions. None of the specimens was regarded as malignant, but in 4 cases FNAC was inconclusive. The inconclusive or false cytological diagnoses had no serious clinical consequences. Among 205 patients with local recurrence identified in the SSG Register 1987-1995, 169 patients were surgically treated. An intralesional or marginal margin was achieved in 110 of these patients, 59 of whom were also given radiotherapy. 54 of the 169 patients had a second local recurrence. The second local recurrence rate was 0.50 if the first local recurrence was treated using surgery with a marginal margin alone, compared to 0.28 if treated using either surgery with a marginal margin and radiotherapy, or a wide margin (p = 0.0008). In extremity STS, the amputation rate for local recurrences was 0.22, compared to 0.09 for primary tumors. The overall 5-year MFS was 0.72 (95% CI 0.68-0.76). High histopathological malignancy grade (Relative Risk 3.0; 95% CI 1.5-6.3) and an inadequate surgical margin (2.9; 95% CI 1.8-4.6) were independent risk factors for local recurrence. High histopathological malignancy grade and large tumor size (> 7 cm) were the most important risk factors for metastasis. Local recurrence was associated with an increased risk of metastasis (4.4; 95% CI 2.9-6.8), but an inadequate surgical margin was not a risk factor for metastasis (1.1; 95% CI 0.8-1.7). In conclusion, it is unlikely that local recurrence of STS is a major source of metastases. It nevertheless represents a costly, complicated and emotionally difficult problem. More radical surgical margins would improve the local recurrence rate, but this can hardly be achieved for center-operated patients without increasing the amputation rate. Instead, local control will improve by giving radiotherapy to all patients after marginal surgery, and to selected patients with wide margins. Radiotherapy is indicated especially after a previous open biopsy or when a local recurrence might lead to an amputation. Furthermore, radiotherapy seems indicated after local recurrence, regardless of margin or grade. The most effective way of reducing costs and detriment associated with local recurrence is to increase referral to sarcoma centers before biopsy or surgery as primary surgical margins would then improve.
Adolescent↗
Leukocyte migration inhibition in patients with Ewing's sarcoma by 3-M potassium chloride extracts of fresh and tissue-cultured Ewing's sarcomas.
Leukocyte migration inhibition (LMI) assays were performed to detect cell-mediated immune reactions against tumor-associated antigens (TAA) of Ewing's sarcoma. With the use of crude antigen preparations obtained by 3M KCl extractions of fresh Ewing's sarcoma or of tissue culture cells derived from a pleural effusion of a Ewing's sarcoma patient, assays were performed with leukocytes from these patients, patients with other cancers, and normal donors. The results demonstrated approximately 60% or greater positive LMI reactivity in Ewing's sarcoma patients, as compared to less than 10% reactivity of normal donors, with the use of extracts of either fresh or tissue-cultured Ewing's sarcoma cells. A lower proportion of positive reactivity was observed in patients with breast and lung cancer. Further specificity tests indicated that a smaller proportion of patients with Ewing's sarcoma had LMI reactivity with KCl extracts of tissue-cultured cells derived from breast cancer of fresh lung cancer cells than did patients with the homologous disease. The results indicate that many patients with Ewing's sarcoma have cell-mediated immunity toward TAA on Ewing's sarcomas. Inasmuch as all the LMI assay were performed with allogeneic extracts, the data also suggested that different Ewing's sarcomas possess common antigens and that some breast and lung cancers may share some TAA with Ewing's sarcoma.
Antigens, Neoplasm↗
Immunoblastic lymphoma in persons with AIDS-associated Kaposi's sarcoma: a role for Kaposi's sarcoma-associated herpesvirus.
Kaposi's sarcoma-associated herpesvirus, the viral agent of Kaposi's sarcoma, is associated with two lymphoproliferative disorders: primary effusion lymphoma and multicentric Castleman's disease. To identify other lymphoproliferative conditions linked with Kaposi's sarcoma-associated herpesvirus, we studied non-Hodgkin's lymphomas arising in individuals with AIDS-associated Kaposi's sarcoma. Formalin-fixed tissues from 24 such lymphomas were examined. As expected, two primary effusion lymphomas were Kaposi's sarcoma-associated herpesvirus-positive, with immunohistochemistry demonstrating the Kaposi's sarcoma-associated herpesvirus latency-associated nuclear antigen in the nuclei of all neoplastic cells. Additionally, three of seven evaluable cases of the immunoblastic variant of diffuse large B-cell lymphoma (immunoblastic lymphoma) showed similar latency-associated nuclear antigen staining. These Kaposi's sarcoma-associated herpesvirus-positive immunoblastic lymphomas resembled primary effusion lymphoma histologically but were not known to involve body cavities (sites included lymph nodes, soft tissues of the neck, and spleen). Notably, 5-20% of the neoplastic cells in the Kaposi's sarcoma-associated herpesvirus-positive immunoblastic lymphomas also showed cytoplasmic staining for viral interleukin-6, a biologically active cytokine homologue found in primary effusion lymphoma. We conclude that Kaposi's sarcoma-associated herpesvirus is present in some immunoblastic lymphomas in persons with AIDS-associated Kaposi's sarcoma.
AIDS-Related Opportunistic Infections↗
Expression of the CD34 antigen distinguishes Kaposi's sarcoma from pseudo-Kaposi's sarcoma (acroangiodermatitis).
The differential diagnosis between Kaposi's sarcoma and the so-called 'pseudo-Kaposi's sarcoma' or acroangiodermatitis of the feet is often fraught with difficulty, not only on clinical but also on histological grounds. The aim of this study was to assess whether immunolabelling for the CD34 antigen, a marker of Kaposi's sarcoma cells, could be of value in the distinction between these two angioproliferative disorders. We comparatively examined 16 biopsy specimens from cases of Kaposi's sarcoma and seven biopsies from patients with pseudo-Kaposi's sarcoma, by a streptavidin-biotin-peroxidase method, using a monoclonal antibody to the CD34 antigen. All cases of Kaposi's sarcoma showed CD34 labelling both on endothelial cells and on the characteristic spindle-shaped, perivascular cells. Biopsies of pseudo-Kaposi's sarcoma showed a strong labelling of endothelial cells of hyperplastic vessels. However, in sharp contrast with Kaposi's sarcoma, a complete absence of perivascular CD34 expression was noted. It seems therefore that immunolabelling for the CD34 antigen appears to be a valuable tool in the differential diagnosis between Kaposi's sarcoma and pseudo-Kaposi's sarcoma.
Acrodermatitis↗
Disseminated Kaposi's sarcoma after heart transplantation: association with Kaposi's sarcoma-associated herpesvirus.
BACKGROUND: Kaposi's sarcoma is an endothelial tumor rarely diagnosed after heart transplantation. We report on a patient originally from Africa in whom Kaposi's sarcoma developed in association with Kaposi's sarcoma-associated herpesvirus. METHODS: A man from Ghana had constitutional symptoms associated with multiple pulmonary nodules that developed 3 months after heart transplantation. Kaposi's sarcoma was diagnosed by thorascopic biopsy. Treatment consisted of reducing immunosuppression therapy and adding famciclovir treatment. Symptoms resolved within 1 month after treatment, and no disease progression was observed for 5 months. The patient died suddenly 8 months after heart transplantation; autopsy revealed occlusion of the left anterior descending coronary artery and grade 3A rejection. Extensive Kaposi's sarcoma was observed in the lungs and gastrointestinal tract at autopsy. RESULTS: Pathologic analysis of the tumor demonstrated features consistent with Kaposi's sarcoma. Polymerase chain reaction and in situ hybridization demonstrated the presence of Kaposi's sarcoma-associated herpesvirus. CONCLUSION: Kaposi's sarcoma rarely is diagnosed after transplantation. Patients infected with Kaposi's sarcoma-associated herpesvirus may be at increased risk. Screening for Kaposi's sarcoma-associated herpesvirus may be indicated in patients at risk. The role of antiviral medications and immunization in the treatment and prevention of the disorder is unknown.
2-Aminopurine↗
Restricted clonality of visceral sarcomas in avian sarcoma virus-infected chickens.
Experiments were undertaken to analyze proviral DNA in primary (wing web) and visceral sarcomas arising in FP chickens infected with BH-RSV(RAV-2). Using the degree of heterogeneity of BH-RSV proviral integration sites as a measure of the degree of polyclonality of sarcoma tissue, we observed that a high proportion of the visceral sarcomas examined comprised dominant clones, independently of whether these sarcomas were isolated from immune-suppressed or nonsuppressed infected chickens; by contrast, a marked heterogeneity of BH-RSV proviral integration sites was noted with primary sarcoma tissue. Several visceral sarcomas containing dominant clones were characterized by the integration of a deleted form of the BH-RSV provirus. In addition, all of the primary and visceral sarcomas exhibited sequences specific for the RAV-2 provirus, and both types of sarcoma tissue were competent for infectious sarcoma virus production.
Animals↗