Antigens tumour-associated

Each tumour usually displays distinct antigen specificity 

Various tumour types display identical tumour-associated antigens (especially if tumours are induced by the same virus) 

The same oncofetal antigen can be expressed by a number of different tumour types 

In contrast to the above situation, cancers induced by viruses generally exhibit immunological cross-reactivity. Any specific virus will often induce expression of the same tumour antigen, no matter what cell type it transforms. Moreover, in some cases, different transforming viruses can induce production of the same tumor antigen(s). Immunodetection/immunotherapy of such cancers is thus rendered attractive. Once a tumour antigen is identified, antibodies raised against it will likely cross-react with several other tumour types. 

DNA viruses, such as adenoviruses and papovaviruses (e.g. polyoma and SV40), induce cellular transformation in rodents. Other viruses have been implicated in human cancers, e.g. Epstein-Barr virus has been implicated with nasopharyngeal carcinoma, /f-cell lymphomas and Hodgkin s lymphoma human papilloma virus is linked to most cervical cancers. 

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In oncology, to study the relationship between the normal and the tumour cell, to detect tumour-associated antigens (CEA, carcino-embryonic antigen, and AFP, a-fetoprotein) and subsequently to enable cancer therapy to be monitored, to locate tumour metastases, and to deliver cytotoxic drugs, toxins, radionuclides, or liposomes to tumour cells. 

Toyokuni, T., and Singhal, A.K. (1995) Synthetic carbohydrate vaccines based on tumour-associated antigens. Chem. Soc. Rev. 24, 231-242. 

Humaspect (Votumumab, human Mab directed against cytokeratin tumour-associated antigen) Organon Teknika Detection of carcinoma of the colon or rectum... 

Clear identification of tumour-associated antigens would facilitate the production of monoclonal antibodies capable of selectively binding to tumour tissue. Such antibodies could be employed to detect and/or destroy the tumour cells. 

Figure 13.4 Binding of appropriate antibody to tumour-associated antigens marks the tumour cell for destruction. This is largely due to the presence of a domain on the antibody Fc region (see also Box 13.2), which is recognized and bound by macrophages and NK cells. Therefore, congregation of such cells on the surface of the tumour is encouraged. This greatly facilitates their cytocidal activity towards the transformed cells...

Table 13.3 Characterizing of tumour-associated antigens. Antigens commonly expressed by a number of different tumour types render practical application of tumour immunodetection/immunotherapy in those cases...

Monoclonal antibodies (MAb) against tumour-associated antigens or growth factors using their intrinsic activity or used as carriers to target cytotoxic drugs, radionuclides and toxins (Section 8.5.1). 

Many different tumour-associated antigens (TAAs) have been described for targeted immunotherapy. General considerations that rationalize the choice of a target antigen are ... 

A number of both pre-clinical and clinical studies have used the folate receptor or EBP as a target for immunotherapy of ovarian carcinoma [31,32]. Expression of this tumour-associated antigen by normal tissues is restricted [33]. The carcinoma-associated antigen, EGP-2, also called EpCAM, is a 38-kDA transmembrane glycoprotein, present on the majority of simple, stratified and transitional epithelia [34]. The biological function of EGP-2 has not yet been established. 

Monoclonal antibodies against tumour-associated antigens or growth factors have been used to target the delivery of cytotoxic drugs, radionuclides and (bacterial) toxins [22]. Simi-... 

The immunoconjugate of doxorubicin with a chimeric anti-Le -related, tumour-associated antigen expressed on most human carcinomas, was evaluated in phase I [132] and phase II [133] clinical trials. The phase II trial performed in patients with metastatic breast carcinoma showed low clinical response rates. These data together with tumour biopsy analysis suggest that the dose that could be safely administered was insufficient to maintain the intra-tu-... 

As discussed in Chapter 3.1.1, reactive cyanine dye derivatives are ideal fluorescent labels for tumour-specific carriers or vehicles, such as antibodies, proteins and peptides. In the literature, a variety of approaches can be found, where such dyes were employed in the design of fluorescent bioconjugates with enhanced selectivity for tumour-associated antigens. 

Indimacis 125 (Igovomab, murine Mab fragment (Fab2) directed against the tumour-associated antigen CA 125)... 

Figure 10.7. Theoretical basis for utilizing monoclonal antibodies conjugated to a cytocidal effector molecule as a cancer therapeutic agent. Binding specificity for tumour-associated antigen renders the antibody a magic bullet , capable of selectively binding to tumour cells...

Masseyeff, R. Assay of tumour-associates antigens. Scand. J. Immunol. 1978, 8 (Suppl. 7), 83-90. 

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