Showing papers on "Cancer cell published in 1973"

Impaired Responsiveness of Lymphocytes and Serum-inhibitory Factors in Patients with Cancer

Abstract: Cellular immune responsiveness, as measured by lymphocyte transformation in one-way mixed-leukocyte cultures and in phytohemagglutinin (PHA)-stimulated cultures, was evaluated in 60 patients with cancer and in 81 normal controls. The effect produced by sera from these subjects on in vitro transformation of lymphocytes was tested on autologous cells and on homologous responding cells from a constant panel of 10 healthy volunteers. The responsiveness of lymphocytes from cancer patients to PHA and to a battery of mitomycin-treated allogeneic cells was significantly lower than that of normal controls. Lymphocyte reactivity in the presence of autologous cancer serum was inversely related to the extent of the disease. Pooled normal serum enhanced the responsiveness of lymphocytes from cancer patients but had no such effect on control cultures from healthy subjects. Sera from cancer patients reduced the PHA and mixed-leukocytc culture responsiveness of normal panel lymphocytes to a level that was significantly lower than that found in the presence of sera from healthy controls. The degree of inhibition produced by cancer sera on the blastogenic response of normal lymphocytes increased with advanced disease. Suppression of lymphocyte transformation was markedly greater in mixed-leukocyte cultures than in cultures exposed to PHA. Out of 60 cancer sera investigated, 23 possessed HL-A reactivity against a random panel of lymphocytes. Our findings demonstrate that serum-inhibitory factors are at least partially responsible for impairment of T-cell responsiveness in cancer patients. It is suggested that isoantigenic modifications on the surface of cancer cells cause the appearance of blocking antibody, with broad cross-reactivity that might bind to the surface of responding and/or target cells.

Hyperthermia (42°C) as an Adjuvant to Radiotherapy and Chemotherapy in the Treatment of the Allogeneic VX2 Carcinoma in the Rabbit

Abstract: As assessed by decrease in tumour volume and inhibition of tumour cell respiration and glycolysis, hyperthermia (intra-tumour temperature 42°C for one hour) potentiated the destructive effect of radiotherapy (1000 rad) on the allogeneic VX2 carcinoma in the hind limb of rabbits, and chemotherapy (methotrexate) produced a similar potentiation of irradiation. The resulting regression of the primary tumour in each case after dual therapy was comparable to that occurring after 3 applications of local hyperthermia, which has been shown to cure 50% of animals with this carcinoma. Combination therapy did not increase the survival time of the rabbits, however, all of which had lung and lymph node metastases at autopsy. The results focus attention on the relationship between a primary tumour and its metastases. The histological picture and the animal survival data suggest that the mechanism of tumour cell death and resorption of necrotic material following treatment may be important in enabling the host to deal with metastatic cells. After combination therapy, many metabolically and mitotically active cancer cells remained in the tumour mass, and the incomplete destruction of the primary tumour may have left the host with a burden of tumour cells too large to be destroyed by the immune system.

Ultrastructural Studies on Regan and Non-Regan Isoenzymes of Alkaline Phosphatase in Human Ovarian Cancer Cells

Abstract: Summary In order to examine the intracellular localization of the Regan isoenzyme of alkaline phosphatase in human cancer cells, ovarian cancer cells from three selected patients were studied histochemically and electron microscopically For selection of these cases, the patients9 ascites or tissue tumor cells derived from primary tumors were smeared or sectioned and stained histochemically for alkaline phosphatase by use of a simultaneous azodye coupling technique with or without amino acid inhibitors (d- and l-phenylalanine and l-homoarginine) in the incubation mixtures These amino acids are able to distinguish the Regan isoenzyme from non-Regan alkaline phosphatases Kaplow9s scoring technique was applied for evaluation of the respective enzyme activities Of the three representative cases selected for this paper, alkaline phosphatase of the cells from Case 1 (S C) revealed high sensitivity only to l-phenylalanine; Case 2 (T C) showed sensitivity to l-phenylalanine and l-homoarginine; Case 3 (H F) showed sensitivity only to l-homoarginine The staining features appeared granular (Cases 1 and 2) and diffuse or membranous (Cases 2 and 3) on light microscopy The tissue cancer cells obtained by surgical operation were processed for electron microscopic examination in combination with the histochemical reaction for alkaline phosphatase with the metal precipitation method of Hugon and Borgers l-Phenylalanine-sensitive cases (Cases 1 and 2) showed enzyme activity on mitochondria of the cancer cells in most of the cells and occasionally in other organelles such as Golgi complexes, endoplasmic reticulum, and nuclear membranes, while in l-homoarginine-sensitive cases (Cases 2 and 3), especially in Case 3, deposition of the enzyme product was distinctly confined to the cell membranes Case 2 also displayed cell membrane activities in addition to the other localizations described From these results, there seemed to exist a likelihood that mitochondrial alkaline phosphatase is related to l-phenylalanine sensitivity, ie, Regan alkaline phosphatase, while the cell membrane activities are sensitive to l-homoarginine ie, non-Regan isoenzyme in ovarian cancer

Identification of normal and abnormal chromosomes in tumor cells

Abstract: The cells of two ascitic effusions from human cancers of the ovary were analyzed by the fluorescence and Giemsa banding techniques. The normal chromosomes still present in the cancer cells were identi

Significance of growth rates, cell kinetics, and histology in the irradiation and chemotherapy of squamous cell carcinoma of the mouth

Abstract: In eight cases of extended tumors of oral cavity, we have studied the growth rate, the cell kinetics parameters, and the histology before and during treatment. We have found that growth rate and cell kinetics are not useful for clinical purposes because the first is not related to the response to treatment, while the second is unable to give relevant parameters in solid human tumors. New information was obtained from examination of serial biopsies before and throughout the treatment. These data suggest that multiple subpopulation groups of cancer cells with different intrinsic sensitivity to chemotherapy and/or radiotherapy may exist in the same tumor. Resistance of the tumor is related to some groups of cells scarcely sensitive to treatment.

Rational chemotherapy: inhibition of polymerase activity of cancer cells.

Abstract: To the Editor.— Recent data indicate that transformation of normal cells by tumor viruses appears to require altered DNA polymerase activity to transcribe new genetic information. Multiple workers have noted the promise for rational cancer chemotherapy of drugs depressing RNA-dependent DNA polymerase ("reverse transcriptase") activity from tumor viruses and human acute leukemia cells. The drugs include rifamycin antibiotics (J Natl Cancer Inst49:761, 1972) and clinically promising sulfhydryl (SH)-inhibitors (Knock et al inOncology, Nov, 1972). At concentrations as low as 10μg/ml, clinically useful SH-inhibitors depress "reverse transcriptase" activity of human leukemic lymphocytes to 12% to 16% of control, activity usually far exceeding that of available rifamycins. The SH-inhibitors were selected by performing three in vitro sensitivity tests on hundreds of human cancers: namely agar plate assay, the Kondo sensitivity test, and radioactive tracer studies monitoring the incorporation of labeled precursors to DNA, RNA, and protein of tumors. The three

Cell recognition and phagocytosis of sv40 transformed cell

Abstract: In the course of cell transformation by SV40 the cell membrane undergoes changes, which in turn cause its surface negatively charged, and decrease markedly the phagocytosis of negatively charged substances. The study of the relationship between such transformed cells and allo-genous hamster red cells as well as lymphocytes has revealed that the rates of adhesion to and ingestion of native cells by the transformed cell, which recognizes the former as self, are low. However, when such native cells are previously treated with half saturated ammonium sulfate and 2.5% glutaraldehyde there occurs a change in the charge of cell membrane and a marked phagocytosis is triggered. In such an instance, when L cells are coated with non-immune albumin or immune sera (anti-RBC-rabbit sera) the phagocytosis is inhibited, but the phagocytosis of transformed cell remains unchanged. The phagocytosis of transformed cells can be inhibited by Concanavalin A treatment of transformed cells and fixed RBC, while be blocking the surface antigen the phagocytosis is enhanced. Therefore, it can be said that the cell recognition of self or non-self by cancer cell depends upon changes in the cell surface of both cell groups, in other words, upon the changes in cell surface charge due to molecular architecture.

The Replication of RNA Tumor Viruses

Abstract: The essential requirement for studying the molecular biology of cancer cells is a tool which can change normal cells into cancer cells Fortunately, this tool is provided by nature itself; cancer is induced upon infection by certain viruses There are DNA and RNA-containing viruses which can transform normal cells into malignant cells as Dr Ponten pointed out

An application of electron microscopic cytochemistry to human tumors

Abstract: Prostatic carcinoma, renal cell carcinoma and melanoma were studied by electron microscopic enzyme cytochemistry. ACPase of prostatic cancer cells was found in lysosomes, secretory vacuoles and vesicles as well as some Golgi apparatuses. The enzyme localizations remained unchanged in tumor cells two weeks after castration when cells were viable. Renal cell carcinomas revealed to have positive ALPase activity at microvilli resembling brush border and lateral plasma membranes facing adjacent tumor cells. The enzyme was negative at basal plasma membrane of the tumor cells. Proximal tubule cells of human kidney showed ALPase activity only at apical membranes. This indicated functional dedifferentiation of plasma membrane in the tumor cells. These observations were verified and substantiated by TPPase, IDPase and G6Pase localizations in tumor cells. The tumor cells also showed positive G6Pase in endoplasmic reticulum. DOPA oxidase was successfully detected in smooth endoplasmic reticulum close to Golgi apparatus, innermost Golgi cisternae and premelanosomes both in cultured melanoma cells and melanoma tissues, which may have diagnostic value. Thus, EM enzyme cytochemistry was considered to be applicable and useful for human cancer study concerning histogenesis, diagnosis and to assess the treatment.