High Degree Of Cytotoxicity Research Articles

Cell-mediated cytotoxicity in vitro of human lymphocytes against a cervical cancer cell line.

Peripheral blood lymphocytes from patients with uterine cervical cancer were tested against a cervical cancer cell line by micro-cytotoxicity assay. In stage O, high degree of cytotoxicity was observed but it decreased with progression of disease. In stage IV and recurrent cases, cytotoxic activity was negligible. Lymphocytes from healthy controls and myoma patients were not cytotoxic against target cells. On the other hand, lymphocyte response of phytohemagglutinin as a nonspecific T-cell activity was as high as the of healthy control in stage O, but the response decreased in stages I to IV and recurrent cases. In stages I to III, several cases showed cytotoxic activity but decreased response to phytohemagglutinin.

Cytotoxic activity of lymphocytes to bronchogenic carcinoma cells in patients with lung cancer.

Cytotoxicity of peripheral blood lymphocytes against a cultured cell line QG-56 of a bronchogenic squamous cell carcinoma was studied by a microcytotoxicity test in 33 cases of bronchogenic carcinoma. An augmented cytotoxicity was detected in the patients in early stages of the disease as compared to normal controls or the patients carrying other types of tumors. The cytotoxicity declined as the stages of cancer advanced. The patients with high degree of cytotoxicity appeared to show better clinical course after radiotherapy.

Catharanthus Alkaloids XIII: Antineoplastic and Hypotensive Activity of Alkaloid Fractions and Certain Alkaloids From Catharanthus lanceus

Hypotensive evaluation of 14 alkaloid fractions derived from C. lanceus roots and leaves in anesthetized, normotensive rats and dogs revealed that eight of the fractions reduced blood pressure from 22–73 per cent for periods ranging from 38 to more than 378 min., at doses of 8–40 mg./Kg. Yohimbine, a potent α-adrenergic blocking agent, was isolated from three of the eight active fractions. However, removal of the yohimbine from one of these fractions did not result in a loss of hypotensive activity, thus indicating that other hypotensive agents may be present. Leurosine, perivine, and pericyclivine elicited only transient hypotensive activity, whereas vindoline, tetrahydroalstonine, ajmalicine, lochnerinine, and periformyline failed to induce a hypotensive response at several dose levels. The same crude alkaloid fractions were evaluated for antineoplastic activity against the P-1534 leukemia with only one of the 14 fractions being active against this neoplasm. Leurosine, isolated from the active fraction, was shown to be a potent antineoplastic alkaloid with a high degree of cytotoxicity. Lochnerinine, although devoid of activity against the P-1534 leukemia, exhibited reproducible cytotoxicity against the 9 KB cell culture. Vindoline, catharanthine, desacetylvindoline, perivine, perivinol, periformyline, pericyclivine, pericalline, catharine, ajmalicine, tetrahydroalstonine, and yohimbine were devoid of P-1534 leukemia activity, as well as cytotoxicity. Monitoring of column chromatographic cuts of the active fraction with the P-1534 leukemia has shown that at least one additional alkaloid, active against this neoplasm, is present.