You can call me whatever names you want, but I believe the core disagreement is your approach is cure/treatment and I'm looking at the root cause/prevention. This is not to suggest zinc deficiency is the culprit, but various deficiencies in the American high calorie diet. From the NIH.gov website:

"Evolving and compelling evidence exists that proves that zinc is implicated as an important cytotoxic/tumor suppressor agent in several cancers. For example, that cellular zinc levels are markedly decreased in prostate cancer is well established" https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3291177/

Zinc: A promising agent in dietary chemoprevention of cancer https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3102454/

"Many epidemiological studies have shown a relationship between the zinc content in the diet and the risk of cancer" https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6835436/

" In addition, zinc contributes to the truncation of the Krebs cycle and inhibition of citrate oxidation, which further prevents cancer cell growth and proliferation, as well as inhibiting the invasion and migration of cancer cells" https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7216164/

"The present meta-analysis suggested that serum zinc levels were significantly lower in lung cancer patients than that in controls." https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6503426/

"In conclusion, we found that highest category of dietary zinc intake can significantly reduce the risk of pancreatic cancer, especially among American populations." https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5463257/

"Increased risk of cancer mortality associated with cadmium exposures in older Americans with low zinc intake" https://pubmed.ncbi.nlm.nih.gov/23151207/

And the list continues: https://www.google.com/search?q=nih.gov+zinc+cancer