[ NEOP ]
Ray...... I think that they are a sincere and decently conceived effort to cure patients. The "concept" is that tumors are capable of eliciting an immune response like a virus or like bacteria.
In fact, experimental tumors often do elicit strong immune responses.......
Int J Cancer 1977 Nov 15;20(5):748-758
Immunity to MCA-induced rat sarcomas: analysis of in vivo and in vitro
results.
Harmon RC, Clark EA, Reddy AL, Hildemann WH, Mullen Y
Three in vivo techniques were used to establish the specificity of tumor immunity induced after sensitization of F344 rats to
syngeneic MCA-induced sarcomas: (1) post-excision resistance to tumor challenge, (2) passive tumor neutralization (the Winn
test), and (3) concomitant immunity. In general, these assays revealed unique non-cross-reactive antigens associated with each
of three sarcomas, FMF1, FMM2, and FMM3. However, spleen cells from tumor-sensitized rats did not demonstrate
cell-mediated cytotoxicity in vitro corresponding to the specificity of tumor resistance in vivo. In the (3H)-proline cytotoxicity
assay, spleen cells from FMM3 tumor-bearing rats or from FMM3 tumor-immune rats were not selectively cytotoxic for
cultured FMM3 target cells. Parallel analysis of spleen cells from normal or FMM3-sensitized rats using the Winn assay and the
(3H)-proline assay revealed that (1) spleen cell cytotoxicity in vitro did not correlate with effective tumor protection in vivo; and
(2) normal spleen cells were cytotoxic against cultured sarcoma target cells in vitro and inhibited tumor growth in vivo. Thus,
passive tumor protection by normal spleen cells in vivo corresponded with the demonstration of natural cytotoxicity in vitro, but
induced specific anti-tumor reactivity was observed only in vivo.
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As you can see, the issue has been close to my heart for a long, long time. The study above was a part of my thesis work. Another part was to conduct similar studies with *spontaneous* cancers, rather than with induced cancers. They didn't work. I could never demonstrate the presence of foreign "antigens" on the surface of spontaneous tumors.
In the intervening 20 years, there have been continuing attempts to develop tumor vaccines. There have thus also been continuing attempts to identify molecules (antigens) that were expressed by the tumors but not expressed by normal tissues. I have never, not once in those 20 years, seen a convincing description of such a molecule.
Dogma says that they exist. Dogma has funded several companies over those 20 years. They are mostly gone now, and the efforts that are most encouraging today are those that try to induce immune responses against molecules that are also expressed, to a limited degree, on normal cells. An example is CRXA...... I've mentioned them over the past few days, based on their ASCO presentation. This is NOT the route chosen by NEOP.
Second problem..... patient-specific therapies just haven't managed to make it. Starting with Biotherapeutics (Franklin and Memphis, TN), they have been flaming failures. Pharmaceutical margins are what is attractive in this business, and you get that from a single therapy that fits all.
So.... NEOP is a sincere effort to make dogma look good. Same old story IMO, new tags. I sincerely hope that I am wrong, and I feel that it's still damn worth trying. I really, really hope that they succeed. However, history tells us to be skeptical, very skeptical, of success.
Disclaimer....... profit seems, of late, to have little relationship to the quality of a concept or of applied science.
Cheers! Rick |
