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)

Skin cancers induced in mice by UV radiation often exhibit a regressor phenotype. In order to determine how tumors escape the immune defenses of the normal immunocompetent host, we sought to isolate progressor variants from a UV radiation-induced C3H mouse regressor fibrosarcoma cell line, UV-2240, by transfection with an activated Ha-ras oncogene. A cotransfection protocol using pSV2-neo DNA, which confers resistance to the antibiotic G418, was used to select transfected cells. Injection of Ha-ras-transfected UV-2240 cells s.c. into immunocompetent C3H mice produced tumors in four of 36 animals. In contrast, UV-2240 cells transfected with pSV2-neo DNA alone or mock transfected with CaPO4 did not produce tumors in normal C3H mice. DNAs from cell lines established from Ha-ras-induced tumors contained unique Ha-ras sequences in addition to those sequences endogenous to UV-2240 cells. However, the Ha-ras-induced progressor variants did not overexpress the Mr 21,000 protein. The Ha-ra-induced progressor variants produced experimental lung metastasis in both normal C3H and nude mice, although they induced more lung nodules in nude mice than in normal C3H mice. In addition, all four Ha-ras-induced progressor variants produced significantly more experimental lung metastases in nude mice than did the parent UV-2240 cell line. However, both the parental UV-2240 cell line and the Ha-ras-induced progressor variants expressed similar levels of H-2Kk and H-2Dk antigens and were immunologically cross-reactive, as determined by in vitro cytotoxic T-lymphocyte and in vivo immunization-challenge assays. These results indicate that the progressor phenotype of the Ha-ras-induced tumor variants is not due to loss of tumor-specific transplantation or Class I major histocompatibility complex antigens. This implies that some tumor cells can escape the immune defenses of the normal immunocompetent host by mechanisms other than loss of tumor-specific transplantation and Class I major histocompatibility antigens.
 ...
PMID:Immune response to progressor variants derived from transfection of an ultraviolet radiation-induced C3H mouse regressor tumor cell line with activated Harvey-ras oncogene. 218 82

Non-melanomatous skin cancers, particularly basal cell and squamous cell carcinomas, are frequently observed in elderly persons and are primarily the result of the chronic, cumulative effects of exposure to sunlight (ultraviolet light radiation). Characteristics of both types of neoplasm and diagnosis and management of non-melanomatous skin cancer are reviewed. Treatment based on multiple factors, including patient age, overall health status, histologic pattern, and cosmetic considerations, is described.
 ...
PMID:Non-melanomatous skin cancer in the elderly: diagnosis and management. 219 8

Langerhans cells (LC) in epidermis are antigen presenting cells. LC may play a role in immune surveillance system and are considered to suppress development of ultraviolet (UV) induced skin cancers. We studied effect of UVB irradiation to LC of xeroderma pigmentosum (XP) and normal subjects by using OKT6 monoclonal antibody. When 3 minimal erythema dose (MED) of UVB were irradiated, density of OKT6 positive LC of XP began to decrease 6 hours after irradiation, and showed the least numbers on day 2 and returned completely to the pre-irradiation level on day 14. Further, after 3 MED irradiation, LCs of both normal subjects became the least on day 3 and returned to the pre-irradiation level on day 14. In XP variant and normal subjects, the number of LC in chronic sun-exposed skin decreased significantly in a similar way comparing to that of non-exposed skin. These results suggest that epidermal LC may not play an essential role in prevention of UV-induced tumor development.
 ...
PMID:[Do OKT6 positive Langerhans cells play a role in the suppression of ultraviolet-induced carcinogenesis?]. 223 92

It has long been held that embryologic fusion planes influence the spread of skin cancer. Embryologic fusion planes have been implicated in the depth of invasion, horizontal spread, and recurrence of cutaneous carcinoma. However, these structures have never been studied in detail. A review of the surgical literature reveals considerable confusion regarding the exact nature, location, and tumor interactions of these fusion planes. We review the gross and microscopic development of sites of embryologic fusion. We examine histologic sections through fusion sites in normally developed adult and fetal fresh cadaver specimens. Our studies, supported by our review of developmental anatomy, indicate that fusion planes do not persist as identifiable anatomic structures that would influence tumor spread.
 ...
PMID:Embryologic fusion planes and the spread of cutaneous carcinoma: a review and reassessment. 224 4

Mohs micrographic surgery is a versatile technique for the treatment of nonmelanoma skin cancers, especially recurrent, invasive, or infiltrating basal cell carcinomas. It provides unsurpassed cure rates by using 100% surgical margin control, and it achieves maximal preservation of normal tissue. At the conclusion of tumor extirpation, the defect is ready for immediate reconstruction. With better understanding of the Mohs micrographic surgery technique, it can be more effectively used as part of a coordinated multidisciplinary approach to the treatment of patients with difficult cutaneous and paracutaneous neoplasms.
 ...
PMID:Mohs micrographic surgery. 225 5

Mohs micrographic surgery has been highly successful in treating skin cancers that grow in a contiguous manner. The technique requires removal of involved tissue in thin layers and histographic mapping to pinpoint residual tumor. This process is repeated until all of the tumor is resected. This allows 100 percent of all margins to be examined and is very tissue conservative, attributing to its unsurpassed cure rates and excellent cosmetic results. Since it is done as an outpatient procedure under local anesthetic, it also is safe and efficient.
 ...
PMID:Mohs micrographic surgery. 227 Jun 80

The incidence of squamous cell carcinoma (SCC) and basal cell carcinoma (BCC) was analyzed separately in all 764 patients who received a renal allograft between 1966 and 1988 at the Leiden University Hospital. The mean follow-up period was 8.7 posttransplant years (range 1-21 years). During this time period 176 skin cancers were diagnosed in 47 patients. The overall risk to develop a first tumor increased from 10% after 10 years to 40% after 20 years of graft survival. The overall incidence of SCC was 250 times higher and that of BCC 10 times higher when compared with the general Dutch population. Moreover the localization of SCCs and BCCs differed considerably. Solar radiation is thought to be an important risk factor for the development of skin cancer. However, the occurrence of skin cancer in long-term graft survivors forms also a major problem in a country with a higher geographical latitude and a moderate amount of sun-exposure, such as the Netherlands.
 ...
PMID:Incidence of skin cancer after renal transplantation in The Netherlands. 231 11

There are epidemiologic similarities between salivary and skin neoplasms that could be attributed to exposure to ultraviolet radiation. To explore further the etiologic parallels between these two types of cancer, we studied the multiple primary association between salivary gland cancer with that of other cancers known to be induced by ultraviolet light exposure, using data from the SEER program for 1973-1984. Because nonmelanoma skin cancers other than cancers of the lip are not routinely reported to the SEER registries, we specifically evaluated the associations with melanoma and lip cancers. Expected numbers of subsequent primaries (melanoma and lip) for the 904 white men and 784 white women with an initial salivary gland cancer were computed from incidence rates using the Connecticut Tumor Registry. There were significantly increased risks for subsequent lip cancer among men (RR = 8.7) and for melanoma among women (RR = 7.1). Among men there was also a significant association between an initial lip cancer and risk of subsequent salivary gland cancer (RR = 12.7). These observations, together with reported increases in incidence of these tumors, suggest a common etiology, which could partly be explained because of exposure to ultraviolet radiation.
 ...
PMID:Salivary gland cancer and risk of subsequent skin cancer. 235 38

Since the late 1970s, 18 clinical studies have been conducted in Japan with various types of human interferon (IFN) for their possible anti-tumor efficacy under the control of the Special Committee for Clinical Application of IFN of the Ministry of Health and Welfare. Objective antitumor effects have been observed in renal cell carcinoma, brain tumor, multiple myeloma, malignant lymphoma, adult T cell leukemia, chronic lymphocytic leukemia, chronic myelogenous leukemia, and by local injections in skin cancer such as malignant melanoma and cutaneous lymphoma. In this paper, updated results of clinical studies of the 3 types of IFNson various malignant tumors in Japan was reviewed, and the potential usefulness of IFNs as the first cytokine introduced into a clinical trial of the treatment of cancer was discussed.
 ...
PMID:[Clinical studies on interferon in cancer therapy in Japan]. 243 62

Mohs' micrographic surgery is used for the treatment of contiguously spreading cancer of the skin. This technique involves removal of tissue in thin layers and precise histographic mapping of all margins of the specimen to determine whether tumor remains. Cure rates are extremely high for the treatment of basal cell carcinoma and squamous cell carcinoma of the skin, especially those known to be at high risk for recurrence. Mohs' micrographic surgery is also tissue sparing because tumor can be precisely identified and removed, and the maximal amount of normal skin can be retained for wound repair. As an outpatient procedure done with the use of local anesthesia, this procedure is both highly effective and safe, and the resultant wounds can be reconstructed in a cosmetically acceptable fashion.
 ...
PMID:Mohs' micrographic surgery. 244 57


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