ABSTRACT
The ruthenium(III) complex imidazolium trans-imidazoledimethylsulfoxide-tetrachlororuthenate (NAMI-A) was tested on TS/A adenocarcinoma cells to evaluate the relationship between cell uptake, cell cycle arrest and cytotoxicity. The in vitro challenge of TS/A cells with 10(-4) M NAMI-A for 15 minutes to 4 hours showed a partial reduction of cell growth only after 4 hour exposure. In the same experimental conditions NAMI-A caused the increase of cells in G2-M cell cycle phase directly proportional on the length of treatment, and the ruthenium uptake by tumour cells, measured by flameless atomic absorption spectroscopy, that increases up to 2 hours of treatment and then reaches a plateau. The arrest of cell cycle in the pre-mitotic G2-M phase was transient and completely reversed by 48 hours after treatment. This study showed that the effect of NAMI-A on the cell cycle of TS/A cells is not strictly related to NAMI-A uptake as is the effect on tumour cell proliferation.
Subject(s)
Adenocarcinoma/drug therapy , Antineoplastic Agents/pharmacology , Antineoplastic Agents/toxicity , Dimethyl Sulfoxide/pharmacokinetics , Dimethyl Sulfoxide/toxicity , G2 Phase , Mitosis , Organometallic Compounds/pharmacokinetics , Organometallic Compounds/toxicity , Cell Cycle/drug effects , Cell Division , Dimethyl Sulfoxide/analogs & derivatives , Flow Cytometry , Ruthenium/pharmacology , Ruthenium Compounds , Spectrophotometry, Atomic , Time Factors , Tumor Cells, CulturedABSTRACT
NAMI-A is a novel antitumour agent, based on ruthenium, which has proved effectiveness against lung metastases of solid mouse tumours. The study focuses on the effects of NAMI-A on leukocyte infiltration into the primary tumour of MCa mammary carcinoma, implanted subcutaneously (s.c.) or intramuscularly (i.m.) into CBA mice. NAMI-A, given with a cycle of daily treatments for six consecutive days on advanced tumours at 35 mg/kg/day, markedly reduces lung metastasis independently of the tumour type (Lewis lung carcinoma, MCa mammary carcinoma or TS/A adenocarcinoma) being treated and of the site of tumour implantation (s.c. or i.m.). The analysis of leukocyte infiltration of the primary tumour, performed on a single cell suspension of cells isolated from a Ficoll gradient on which a raw suspension of primary tumour cells was layered, showed NAMI-A to significantly increase tumour infiltrating lymphocytes. These lymphocytes are almost all CD3+ cells with a significant increase of the CD8+ over the CD4+ subpopulation that reduces the helper/suppressor ratio from 2.8 to 2.1. These data indicated the absence of toxicity of NAMI-A for tumour infiltrating lymphocytes and suggested that this compound might even synergize in combined treatments with cancer immunotherapy.
Subject(s)
Adenocarcinoma/immunology , Antineoplastic Agents/therapeutic use , Carcinoma, Lewis Lung/immunology , Dimethyl Sulfoxide/analogs & derivatives , Lung Neoplasms/secondary , Lymphocytes, Tumor-Infiltrating/immunology , Mammary Neoplasms, Experimental/immunology , Organometallic Compounds/therapeutic use , T-Lymphocytes/immunology , Adenocarcinoma/drug therapy , Animals , Carcinoma, Lewis Lung/drug therapy , Dimethyl Sulfoxide/therapeutic use , Dose-Response Relationship, Drug , Female , Humans , Lung Neoplasms/immunology , Lung Neoplasms/prevention & control , Mammary Neoplasms, Experimental/drug therapy , Mice , Mice, Inbred BALB C , Mice, Inbred CBA , Ruthenium Compounds , T-Lymphocytes/classificationABSTRACT
The growth capacity and adaptation of TS/A and TS/A-IL4 lines on laminin, fibronectin, collagens I and IV and matrigel compared to plastics were studied by flow cytometry. On plastic plates, TS/A-IL4 grows in vitro more slowly than the TS/A line and shows a more differentiated phenotype. TS/A-IL4 cells loose the capacity to bind lymphocytes and peroxidase positive cells obtained from mice implanted with the same tumour. The ratio between fibroblast- and epithelial-like cells of TS/A adenocarcinoma is subjected to marked modifications depending on the substrate on which the two cell lines are grown. IL4 release per cell unit is increased by collagen I as is the number of CD54 positive cells, suggesting that, at least in part, the in vivo rejection of TS/A-IL4 tumor might be ascribed to the stimulatory effect of the tissue on the IL4 release by tumor cells. The overall result is that gene modified TS/A-IL4 line shows marked changes of behaviour, most of them depending on the substrate on which tumor cells are growing.
