Biomaterial Database

Human tumor cells resistant to verapamil. 1989

K R Huber, and W F Schmidt, and B al-Assaad, and R W Neuberg, and R S Ettinger

Children's Cancer Research Laboratory, Department of Pediatrics, School of Medicine, University of South Carolina, Columbia 29208.

The efficacy of the calcium channel blocker verapamil for enhancing at low concentrations the cytotoxicity of unrelated antineoplastic drugs and for inhibiting at high concentrations cell proliferation has stimulated interest in the underlying mechanisms of these two diverse effects. We have selected two human brain tumor cell lines (a TE671 medulloblastoma and a A172 glioma line) for resistance against 100 uM verapamil to aid in the elucidation of the mechanism of verapamil's antiproliferative effect. Our first experiments on the selected TE671 medulloblastoma cells show that, in the presence of 100 uM verapamil, these cells grow at a rate similar to that observed for the sensitive cells in the absence of verapamil. This resistant clone continues to exhibit resistance toward verapamil for at least three days after the verapamil has been removed from the growth medium. In contrast to the sensitive cells, the resistant cells show only slight cell cycle phase alterations after removal of verapamil from the growth medium. This, together with an unchanged c-myc gene expression after removal of verapamil, indicates a stable phenotypic alteration that is responsible for the exhibited resistance toward the antiproliferative effects of the drug. Experiments designed to elucidate the mechanism of resistance showed that these cells are not cross-resistant to the antineoplastic drugs vincristine and adriamycin. Also, the resistance is not accompanied by increased amounts of the 170-180 kDa P-glycoprotein that has been implicated in resistance phenomena of cancer cells towards antineoplastic drugs.

UI	MeSH Term	Description	Entries
D007700	Kinetics	The rate dynamics in chemical or physical systems.
D008527	Medulloblastoma	A malignant neoplasm that may be classified either as a glioma or as a primitive neuroectodermal tumor of childhood (see NEUROECTODERMAL TUMOR, PRIMITIVE). The tumor occurs most frequently in the first decade of life with the most typical location being the cerebellar vermis. Histologic features include a high degree of cellularity, frequent mitotic figures, and a tendency for the cells to organize into sheets or form rosettes. Medulloblastoma have a high propensity to spread throughout the craniospinal intradural axis. (From DeVita et al., Cancer: Principles and Practice of Oncology, 5th ed, pp2060-1)	Arachnoidal Cerebellar Sarcoma, Circumscribed,Medulloblastoma, Desmoplastic,Medullomyoblastoma,Sarcoma, Cerebellar, Circumscribed Arachnoidal,Medulloblastoma, Adult,Medulloblastoma, Childhood,Melanocytic Medulloblastoma,Adult Medulloblastoma,Adult Medulloblastomas,Childhood Medulloblastoma,Childhood Medulloblastomas,Desmoplastic Medulloblastoma,Desmoplastic Medulloblastomas,Medulloblastoma, Melanocytic,Medulloblastomas,Medulloblastomas, Adult,Medulloblastomas, Childhood,Medulloblastomas, Desmoplastic,Medulloblastomas, Melanocytic,Medullomyoblastomas,Melanocytic Medulloblastomas
D009693	Nucleic Acid Hybridization	Widely used technique which exploits the ability of complementary sequences in single-stranded DNAs or RNAs to pair with each other to form a double helix. Hybridization can take place between two complimentary DNA sequences, between a single-stranded DNA and a complementary RNA, or between two RNA sequences. The technique is used to detect and isolate specific sequences, measure homology, or define other characteristics of one or both strands. (Kendrew, Encyclopedia of Molecular Biology, 1994, p503)	Genomic Hybridization,Acid Hybridization, Nucleic,Acid Hybridizations, Nucleic,Genomic Hybridizations,Hybridization, Genomic,Hybridization, Nucleic Acid,Hybridizations, Genomic,Hybridizations, Nucleic Acid,Nucleic Acid Hybridizations
D002453	Cell Cycle	The complex series of phenomena, occurring between the end of one CELL DIVISION and the end of the next, by which cellular material is duplicated and then divided between two daughter cells. The cell cycle includes INTERPHASE, which includes G0 PHASE; G1 PHASE; S PHASE; and G2 PHASE, and CELL DIVISION PHASE.	Cell Division Cycle,Cell Cycles,Cell Division Cycles,Cycle, Cell,Cycle, Cell Division,Cycles, Cell,Cycles, Cell Division,Division Cycle, Cell,Division Cycles, Cell
D002455	Cell Division	The fission of a CELL. It includes CYTOKINESIS, when the CYTOPLASM of a cell is divided, and CELL NUCLEUS DIVISION.	M Phase,Cell Division Phase,Cell Divisions,Division Phase, Cell,Division, Cell,Divisions, Cell,M Phases,Phase, Cell Division,Phase, M,Phases, M
D002460	Cell Line	Established cell cultures that have the potential to propagate indefinitely.	Cell Lines,Line, Cell,Lines, Cell
D002528	Cerebellar Neoplasms	Primary or metastatic neoplasms of the CEREBELLUM. Tumors in this location frequently present with ATAXIA or signs of INTRACRANIAL HYPERTENSION due to obstruction of the fourth ventricle. Common primary cerebellar tumors include fibrillary ASTROCYTOMA and cerebellar HEMANGIOBLASTOMA. The cerebellum is a relatively common site for tumor metastases from the lung, breast, and other distant organs. (From Okazaki & Scheithauer, Atlas of Neuropathology, 1988, p86 and p141)	Benign Cerebellar Neoplasms,Cerebellar Cancer,Malignant Cerebellar Neoplasms,Cerebellar Neoplasms, Benign,Cerebellar Neoplasms, Malignant,Cerebellar Neoplasms, Primary,Cerebellar Tumors,Neoplasms, Cerebellar,Neoplasms, Cerebellar, Benign,Neoplasms, Cerebellar, Malignant,Neoplasms, Cerebellar, Primary,Primary Neoplasms, Cerebellum,Benign Cerebellar Neoplasm,Cancer, Cerebellar,Cerebellar Cancers,Cerebellar Neoplasm,Cerebellar Neoplasm, Benign,Cerebellar Neoplasm, Malignant,Cerebellar Neoplasm, Primary,Cerebellar Tumor,Cerebellum Primary Neoplasm,Cerebellum Primary Neoplasms,Malignant Cerebellar Neoplasm,Neoplasm, Benign Cerebellar,Neoplasm, Cerebellar,Neoplasm, Cerebellum Primary,Neoplasm, Malignant Cerebellar,Primary Cerebellar Neoplasm,Primary Cerebellar Neoplasms,Primary Neoplasm, Cerebellum,Tumor, Cerebellar
D004317	Doxorubicin	Antineoplastic antibiotic obtained from Streptomyces peucetius. It is a hydroxy derivative of DAUNORUBICIN.	Adriamycin,Adriablastin,Adriablastine,Adriblastin,Adriblastina,Adriblastine,Adrimedac,DOXO-cell,Doxolem,Doxorubicin Hexal,Doxorubicin Hydrochloride,Doxorubicin NC,Doxorubicina Ferrer Farm,Doxorubicina Funk,Doxorubicina Tedec,Doxorubicine Baxter,Doxotec,Farmiblastina,Myocet,Onkodox,Ribodoxo,Rubex,Urokit Doxo-cell,DOXO cell,Hydrochloride, Doxorubicin,Urokit Doxo cell
D004351	Drug Resistance	Diminished or failed response of an organism, disease or tissue to the intended effectiveness of a chemical or drug. It should be differentiated from DRUG TOLERANCE which is the progressive diminution of the susceptibility of a human or animal to the effects of a drug, as a result of continued administration.	Resistance, Drug
D005910	Glioma	Benign and malignant central nervous system neoplasms derived from glial cells (i.e., astrocytes, oligodendrocytes, and ependymocytes). Astrocytes may give rise to astrocytomas (ASTROCYTOMA) or glioblastoma multiforme (see GLIOBLASTOMA). Oligodendrocytes give rise to oligodendrogliomas (OLIGODENDROGLIOMA) and ependymocytes may undergo transformation to become EPENDYMOMA; CHOROID PLEXUS NEOPLASMS; or colloid cysts of the third ventricle. (From Escourolle et al., Manual of Basic Neuropathology, 2nd ed, p21)	Glial Cell Tumors,Malignant Glioma,Mixed Glioma,Glial Cell Tumor,Glioma, Malignant,Glioma, Mixed,Gliomas,Gliomas, Malignant,Gliomas, Mixed,Malignant Gliomas,Mixed Gliomas,Tumor, Glial Cell,Tumors, Glial Cell