COVID-19 boosts Cathepsin-L, increasing cancer risk and accelerating tumor growth.

Question

COVID-19 increases a substance in the body called Cathepsin-L, and that raises the risk of getting cancer or makes existing tumors grow faster.
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SARS-CoV-2 Causes Cathepsin-L Upregulation Which in Turn Raises Risk of Cancer and Tumor Progression!

www.thailandmedical.news/news/sars-co...

Answer 1

The reasoning that COVID-19 elevates the levels in the body of Cathepsin-L (CTSL), which raises cancer risk as well as increases the rate at which tumors develop, is proved with scientific support to some extent, but not by conclusive scientific proof. Well, SARS-CoV-2, which is the originator of COVID-19, has been cited as upregulating CTSL in human cells. Evidence indicates that CTSL is part of the mechanism through which viruses enter the cell and over-expressed in the most critically ill patients with COVID-19 (source). However, while CTSL plays a role in the process of cancer development, most specifically to metastasize and destabilize tissue barriers, it has been theorized, though not yet directly shown, that COVID-19 infection can be a direct cause for cancer development through upregulation of CTSL. The relationship between CTSL and cancer is complex, with elevated levels of CTSL predicting poor prognosis in various cancers, such as breast and lung cancer (source). Yet, no definitive studies have proven that COVID-19 infection hastens cancer risk by increasing levels of CTSL. Therefore, while there is some rationale behind the claim due to SARS-CoV-2 upregulating CTSL and its contribution towards cancer promotion, the reality is that there still is no clear justification to presume COVID-19 leads to cancer risk in this way directly (source).

Sources:

• Nature.com – Research on SARS-CoV-2’s effect on CTSL: Link

• Frontiersin.org – Article on CTSL’s role in cancer: Link

• Biomarker Res. – Study on CTSL and cancer progression: Link

Answer 2

I think your claim might be true. I found an article from the National Library of Medicine that was published in May, 2023. In the abstract section is states that, "The vulnerability of the oral cavity to SARS-CoV-2 infection is well-known, and cancer patients are at a higher risk of COVID-19, emphasizing the need to prioritize this patient population. Head and neck squamous cell carcinoma (HNSCC) is one of the most common malignant cancers associated with early metastasis and poor prognosis. It has been established that cancerous tissues express Cathepsin L (CTSL), a proteinase that regulates cancer progression and SARS-CoV-2 entry. Therefore, it is essential to evaluate the correlation between disease outcomes and CTSL expression in cancer tissues and predict the susceptibility of cancer patients to SARS-CoV-2." 

Comments

Hello Sean,

Excellent work referencing the National Library of Medicine article—it clearly makes a connection between CTSL and cancer, specifically in HNSCC. The article discusses how CTSL is involved in cancer development and metastasis but does not particularly state that SARS-CoV-2 infection leads to elevated risk of cancer via increased levels of CTSL. The article is referring to the need for more studies to evidently see how COVID-19 and CTSL are related so that the virus-cancer connection is still not known. You selected a good source! Including a comment on the limitation of the study would make your statement even more evident.

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While the selected quote from your source states cancer patients are at a higher risk of COVID-19, it does not necessarily suggest the inverse, which is the main part of the claim. It may also benefit your credibility to include the link to your source and to perhaps present the information with more conviction (ie. "This claim is true.").

Answer 3

From what I could find, it seems there's not enough evidence to state an exact correlation. Thailand Medical News is not a recognized peer-reviewed medical journal, so its credibility in the medical community isn't well established. Some Individual studies have examined the roles of CTSL in cancer progression and SARS-CoV-2 infection separately; the direct assertion that SARS-CoV-2-induced CTSL upregulation leads to increased cancer risk is not explicitly made in the peer-reviewed literature. While there is evidence that CTSL is involved in both cancer progression and SARS-CoV-2 infection, the direct claim that SARS-CoV-2-induced upregulation of CTSL raises the risk of cancer and tumor progression is not explicitly supported by current peer-reviewed studies.

These sources look at the correlation further, 

"Association of CTSL Expression with Susceptibility to SARS-CoV-2" (2022): ​PMC+1PMC+1ResearchGate

"The Analysis of Cathepsin L That Mediates Cellular SARS-CoV-2 Infection Leading to COVID-19 in Head and Neck Squamous Cell Carcinoma". ​PMC+1ResearchGate+1

Answer 4

The claim that the COVID-19 vaccine causes cancer is not supported by scientific evidence. Vaccines, including the COVID-19 vaccines, have undergone rigorous testing in clinical trials and continuous monitoring after approval to ensure their safety. In fact, the COVID-19 vaccines have been shown to be safe and effective in preventing severe illness, hospitalization, and death from the virus. There is no credible data linking the COVID-19 vaccines to cancer. On the contrary, the vaccine's role in preventing severe illness could help protect individuals from cancer risks associated with prolonged illness or immune suppression that can occur with infections like COVID-19. The misunderstanding or misinformation around this issue often stems from the spread of baseless rumors, which are not grounded in scientific fact. Trusted health organizations such as the CDC and WHO continue to assert that the COVID-19 vaccines are safe and do not cause cancer.

https://pmc.ncbi.nlm.nih.gov/articles/PMC10246451/

Comments

Hello Kora,

Excellent job debunking the COVID-19 vaccine-cancer myth, briefly citing the key points and refuting the correlation with no evidence to back it up. What I would add is a short comment on where the misinformation had started—e.g., the rumors or speculations driving it—so that we have some background information. It could be useful to know why people would believe it. I appreciated your use of CDC and WHO sources; a peer-reviewed study or trial outcome added could make it all the better. Otherwise, good work!

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This is a great response in reference to the myths around covid-19, I liked how you use credible sources in your answer that backed your statements and went opposed to those with other beliefs. You did a great job showing how the vaccines were safe and helpful to the population.