Digging the root | Is there a miracle anti-cancer drug that can kill all solid tumors? I'm afraid it's too early!

gossip

Recently, all major platforms have been pushing a piece of news: " A scientific research institute in the United States has developed a drug that can kill all solid tumors ", as if conquering cancer is just around the corner.

Is this really the case? Has the cancer problem that has troubled mankind for many years been solved?

analyze

Regarding this study, we suggest that everyone should be cautiously optimistic and not blindly optimistic. Although the new drug AOH1996 has the potential to fight cancer in principle, it has only completed in vitro and animal experiments. Whether it can become a true anti-cancer drug requires more experimental and clinical data.

The image is from reference [1]. This drug paper that sparked discussion was published in Cell Chemical Biology. The main content of the article was to analyze the mechanism and effect of the drug. The author did not mention killing all solid tumors in the title and highlights.

What exactly is the new drug AOH1996?

Let’s first take a brief look at what kind of drug this is.

This drug (AOH1996) is a cancer cell targeted drug.

Targeted cancer drugs are a class of drugs that specifically target specific molecular targets in the growth and division mechanisms of tumor cells . Compared with traditional chemotherapy drugs, these drugs work more precisely and aim to reduce damage to normal cells.

The target of AOH1996 is called proliferating cell nuclear antigen.

Let us briefly explain proliferating cell nuclear antigen.

Proliferating Cell Nuclear Antigen (PCNA) is a protein that acts as a cell cycle regulator. During cell division, especially during DNA replication, the expression of PCNA increases significantly.

The image shows the PCNA protein structure in Arabidopsis thaliana, from reference source [2]

PCNA is a ring-shaped protein complex that plays a key role in DNA synthesis as a cofactor of DNA polymerase δ. Through interaction with other proteins, PCNA can promote the binding of DNA polymerase to DNA templates, thereby improving the efficiency and accuracy of DNA synthesis.

PCNA is involved in many DNA metabolic processes, such as DNA repair and chromatin assembly, etc. Therefore, it plays an important role in cell cycle regulation, DNA damage repair, and the occurrence and development of cancer.

Therefore, it can be used clinically to detect the expression level of PCNA to detect the growth rate of tumor cells.

Is it possible to inhibit the PCNA of cancer cells?

Can it inhibit the growth of tumor cells?

The logic seems to be correct. The drug targets a mutation in PCNA that only occurs in cancer cells. Using drugs against this mutated PCNA can cause the cancer cells to not replicate normally, and eventually cause the cancer cells to die. Because normal cells do not have this mutation in their PCNA, normal cells will not be harmed.

During the experiment, the researchers conducted many in vitro cell experiments and animal experiments, and the results showed that AOH1996 can cause cancer cells to die while normal cells are not affected.

The above figure is the result of the animal experiment in the article, where CDE represents the anti-cancer activity of AOH1996 in mice with xenograft tumors of neuroblastoma, breast cancer and small cell lung cancer cells, respectively. Compared with the control group, daily AOH1996 treatment significantly reduced the tumor burden of mice.

What is the new drug AOH1996

Is it a miracle drug against cancer?

Does this look optimistic? If this thing really works, can it treat all solid tumor cancers?

Here we come back to the old question.

Bullets can also destroy all solid tumors.

Every drug that comes to market must undergo in vitro experiments, animal experiments, and phase I, II, and III clinical trials, during which it will undergo various clinical studies and reviews.

Only when a drug shows definite efficacy in clinical trials can we consider it effective. However, if it is effective in in vitro experiments or animal experiments, we cannot really say that the drug will be equally effective in humans. That is why there is the most popular saying: "Bullets can also destroy all tumors in vitro."

In fact, every year, a large number of new drugs show good effects in vitro, but then fail in animal experiments or clinical trials. This is a very common situation. From in vitro experiments to the final drug launch, one in a hundred is a good saying, and the probability of one in a thousand or even ten thousand is more likely.

Currently, this experiment mainly carried out in vitro experiments and animal experiments, and is currently in Phase I clinical trials. Although Phase I clinical trials are mainly used to test the safety and dosage of drugs, for cancer patients, Phase I can also show some of the drug's effectiveness.

Therefore, if we really want to say that this drug is effective, we have to wait for its clinical results.

There is still a long way to go for anti-cancer drugs.

There is another point that needs to be made clear to everyone. Drugs that can eliminate most solid tumors have long been available, such as our common chemotherapy drugs cisplatin and doxorubicin. But the problem is that drugs that can kill all tumor cells are likely to kill normal cells as well, killing one thousand enemies while injuring eight hundred or even one thousand and two hundred of their own. But even so, there is no guarantee that these chemotherapy drugs can treat all solid tumors.

This drug is a targeted drug, which means it tries to kill only cancer cells without damaging normal cells.

When pursuing precision, it is impossible to require breadth, which is a very easy thing to understand. Similarly, it is difficult to expect a targeted drug to solve all problems.

in conclusion

Cancer is a collection of complex diseases, and even the same type of cancer has its own specificity. Although the PCNA target selected by this drug seems to cover a very large number of tumors, it can be seen from their own paper data that there are still some tumors where the drug is not effective, and it cannot even be ruled out that it is completely ineffective.

At the same time, considering the complex specificity of tumors and the problem of drug resistance, it is possible that the drug may be effective at the beginning, but drug escape may occur after a while. This is actually very common in clinical practice.

We very much hope that this drug can show good clinical results and provide new ideas and means for tumor treatment. However, expecting one target or one drug to treat all solid tumors is still just a beautiful vision at present.

Author: Lengzhe popular science author

Reviewer: Li Le, Professor of Shihezi University School of Pharmacy, Standing Committee Member of the Teaching and Popular Science Committee of the Chinese Pharmacological Society

References:

[1]https://www.cell.com/cell-chemical-biology/fulltext/S2451-9456(23)00221-0?_returnURL=https%3A%2F%2Flinkinghub.elsevier.com%2Fretrieve%2Fpii%2FS2451945623002210%3Fshowall%3Dtrue

[2]https://academic.oup.com/aob/article/107/7/1127/127557?login=false.

This article is produced by Science Refutes Rumors. Please indicate the source when reprinting. The cover image of this article is from the copyright library. Reprinting and quoting may cause copyright disputes.