b-428 and Breast-Neoplasms

In this work, the benzimidazole-pyrrole conjugates 6a-h and benzimidazole-tetracycles conjugates 12-14 were prepared. The cytotoxicity of the compounds 3, 4a-h, 6a-h, 8, 10 and 12-14 was tested against lung cancer cell line A549. Compound 6b exhibited higher activity than the bis-benzoxazole natural product (UK-1), the standard. The tested 4g,h, 6a-h, 10 and 12-14 exhibited remarkable cytotoxicity activity against breast cancer cell line MCF-7 with higher activity than tamoxifen. Furthermore, compound 4h was found to be also more potent than doxurubicin. The antitumor promotion activity of synthesized compounds 4g,h, 6a-h, 10 and 12-14 has been estimated by studying their possible inhibitory effects on EBV-EA activation induced by 12-O-tetradecanoylphorbol-13-acetate (TPA). Among the studied compounds, the inhibitory activities of compounds 8, 13 and 14 demonstrated strong inhibitory effects on the Epstein-Barr virus early antigen (EBV-EA) activation without showing any cytotoxicity on the Raji cells and their effects being stronger than that of a representative control, oleanolic acid. Moreover, the molecular docking of the new compounds into plasminogen activator (uPA) receptor has been in correlation with the antitumor activity. All synthesized compounds 3, 4a-h, 6a-h, 8, 10 and 12-14 were docked into same groove of the binding site of the native co-crystalized (4-iodobenzo[b]thiophene-2-carboxamidine) ligand (PDB code:1c5x) for activity explaination. Compounds 4h, 6b and 13, giving the best docking results, were further studied to estimate their effect on the level of uPA using AssayMax human urokinase (uPA) ELISA kit. In case of A549 cell line, compound 6 exhibited similar activity to MMC, and for MCF-7 cell line, compound 4h exhibited similar activity to doxorubicin, in inhibiting the expression of uPA.

Topics: Antineoplastic Agents; Benzimidazoles; Breast Neoplasms; Cell Line, Tumor; Drug Screening Assays, Antitumor; Herpesvirus 4, Human; Humans; Lung Neoplasms; MCF-7 Cells; Models, Molecular; Pyrroles; Structure-Activity Relationship; Tetracyclines; Virus Activation

Inhibition of urokinase plasminogen activator (uPA) has been shown to suppress cancer cell invasion and metastasis in the laboratory setting by numerous investigators. Most studies have used murine cell lines implanted in syngeneic rodents or transfected human cell lines grown in immunocompromised laboratory hosts. In this study using Matrigel invasion chambers and two separate uPA inhibitors, amiloride and B428, the invasive capacity of unaltered human breast cancer cells was significantly suppressed. Cell proliferation was also suppressed to a lesser degree. These findings suggest that uPA inhibition may be a valid clinical approach to the control of the invasion and metastasis of human cancers.

Topics: Amidines; Amiloride; Breast Neoplasms; Cell Division; Humans; Neoplasm Invasiveness; Serine Proteinase Inhibitors; Thiophenes; Tumor Cells, Cultured

Urokinase (urokinase plasminogen activator, uPA) and its cell surface receptor (uPA receptor, uPAR) play an important role in a variety of physiological and pathological processes requiring cell migration and tissue remodeling. Using our syngeneic model of uPAR overexpression by the rat breast cancer cell line Mat B-III, we have examined the ability of the nonsteroidal antiestrogen, tamoxifen (TAM), and of a selective synthetic inhibitor of uPA, 4-iodo benzo[b]thiophene-2-carboxamidine (B-428), to inhibit expression of uPA and uPAR as well as cell growth, invasion, and metastasis of wild-type Mat B-III cells and of cells overexpressing uPAR (Mat B-III-uPAR). Both TAM and B-428 inhibited uPAR gene transcription, mRNA expression, protein production and also decreased the proliferative and invasive capacity of Mat B-III and Mat B-III-uPAR. The effects of TAM and B-428 were more pronounced when these agents were tested in combination. Both control and experimental cells (1 x 10(6) cells) were inoculated orthotopically into the mammary fat pad of syngeneic female Fisher rats, and animals were infused i.p. with either TAM and B-428 alone or in combination for 2 weeks. Control animals receiving vehicle alone developed large tumors and macroscopic metastases to lungs, liver, and lymph nodes. In contrast to this, experimental animals receiving TAM and B-428 showed a significant decrease in primary tumor volume and metastases. Combination therapy had especially marked effects in blocking progression of the primary tumor in experimental animals inoculated with highly aggressive Mat B-III-uPAR cells. These results underscore the utility of anti-proteolytic agents (B-428) in addition to standard hormone therapy (TAM) in advanced breast cancer patients where the uPA/uPAR system plays a key role in tumor progression.

Topics: Amidines; Animals; Antineoplastic Agents, Hormonal; Breast Neoplasms; Cell Division; Drug Screening Assays, Antitumor; Estrogen Antagonists; Female; Neoplasm Invasiveness; Rats; Rats, Inbred F344; Receptors, Cell Surface; Receptors, Urokinase Plasminogen Activator; RNA, Messenger; Tamoxifen; Thiophenes; Transcription, Genetic; Urokinase-Type Plasminogen Activator