Method for the identification and use of substances that modulate POD function and/or structure

Abstract

The invention disclosed herein comprises assay methods for identifying substances useful for treating pathogenic disorders. The assay methods disclosed herein are based on the discovery that POD function and structure are key elements in normal transcriptional processes. Disruption of POD function and / or structure contributes to the creation and / or maintenance of a variety of pathogenic disorders.

Description

[0001] This application claims the benefit of U.S. application Ser. No. 08 / 975,272, filed Nov. 21, 1997, now pending, which is hereby incorporated by reference herein in its entirety.[0002] This invention relates to assay methods that can be used to identify substances valuable in the treatment of pathogenic disorders. In a particular aspect, the invention relates to assay methods for identification of substances useful for treatment of disorders related to transcription, translation and replication such as viral infections, cancer, inflammatory disorders and in particular disorders involving nuclear receptor functioning. In another aspect, the invention relates to methods for using substances, identified employing assay methods of the invention, for the treatment of pathogenic disorders. An additional aspect of the invention relates to methods for evaluating viral vectors for their usefulness in gene therapy.[0003] Some of the processes by which a cell utilizes its genetic material...

AI Technical Summary

Benefits of technology

[0020] In accordance with another aspect of the present invention, it has further been discovered that restoration of POD function and / or structure has a beneficial treatment effect and can contribute to restoration of normal function in the organism so effected.

[0024] In one aspect of the present invention, a test substance can be identified as a potentially useful therapeutic agent by its ability to enhance or restore POD function and / or structure by increasing levels of a POD-localized protein. The inventors have discovered that an increase in the levels of POD-localized proteins has a beneficial therapeutic effect on cells infected with viruses that cause serious disease in humans, such as the human T-lymphotropic virus (HTLV-1) which is associated with adult T-cell leukemia (ATLL) and inflammatory neurological diseases such as tropical spastic paraparesis (TSP). As seen in the Examples below, increasing the expression of the POD-localized protein PML reverses the pathogenic effects of the HTLV-1 protein Tax.

[0036] It is known that the oncoprotein Tax, a key protein in the replication of HTLV-1 and HIV-1, activates the transcriptional coactivator NF-.kappa.B. It is also known that NF-.kappa.B inhibits nuclear receptor function. In accordance with the present invention, it has been discovered that Tax expression also inhibits nuclear receptor function, showing a synergistic effect with NF-.kappa.B, and additionally disrupts normal POD morphology. These effects can be overcome by increased expression of a POD-localized protein, for example PML. Furthermore, in accordance with the present invention, it has been discovered that the transcription factor CBP, an essential coactivator of nuclear receptor activity, localizes to the POD through its binding to the POD-localized protein PML. This work strongly suggests that a modulator of POD function and / or structure would have a beneficial effect in treating disorders dependent on nuclear receptor function.

[0051] Agents intended to be administered intracellularly may be administered using techniques well known to those of ordinary skill in the art. For example, such agents may be encapsulated into liposomes, then administered as described above. Liposomes are spherical lipid bilayers with aqueous interiors. All molecules present in an aqueous solution at the time of liposome formation are incorporated into the aqueous interior. The liposomal contents are both protected from the external microenvironment and, because liposomes fuse with cell membranes, are efficiently delivered into the cell cytoplasm. Small organic molecules may be directly administered intracellularly due to their hydrophobicity.

Problems solved by technology

In fact, PML:RAR forms homodimers and PML:RAR-PML heterodimers in vitro, which results in disruption of normal POD structure and may contribute to the oncogenic state in APL patients.

Current anti-inflammatory treatments strive to ameliorate the undesirable effects of these proteins with varying degrees of success, often producing severe side effects.

Disruption of normal transcription can result in an inability of cells to differentiate, for example, a hallmark of the cancerous state.

Viral infections, such as with the human immunodeficiency virus, can have a severe debilitating effect on the infected host.