Is a malignant tumor cancer? Early treatment is the key

Malignant tumors are cancers. There are now more and more types of malignant tumors. The most important thing in treating tumors is to discover them as early as possible and treat them scientifically to control the spread of the disease. Patients with malignant tumors must also maintain a good attitude.

1. Is a malignant tumor cancer?

A tumor is a new growth formed when cells in local tissues lose normal regulation of their growth at the genetic level under the influence of various tumorigenic factors, leading to abnormal proliferation of cells. It includes two major categories: benign tumors and malignant tumors. Malignant tumors that originate from epithelial tissue are called cancers, such as skin cancer, esophageal cancer, etc. Malignant tumors that originate from mesenchymal or connective tissue are called sarcomas, such as osteosarcoma, lymphosarcoma, etc. Therefore, malignant tumors include two major categories: cancer and sarcoma. Cancer is a general term for more than 100 related diseases, which means that malignant tumors are just a general term, which can be subdivided into many specific tumors. Such as: uterine cancer, ovarian cancer, etc. Therefore, the treatment of malignant tumors should also be classified and symptomatic. In short, it is important to detect the disease early and never wait until it reaches the advanced stage where cancer cannot be treated.

2. Treatment Methods

Gene-virus therapy method: There are certain differences in gene expression between normal cells and tumor cells, which means that the genes that are necessary for some viruses to replicate in normal cells are not needed in tumor cells. Therefore, the removal of these genes is expected to allow them to replicate specifically in tumor cells but not in normal cells. Taking adenovirus (AdV) as an example, p53 is the main protein of host cells to resist adenovirus. After normal cells are infected by adenovirus, p53 is immediately activated, leading to cell apoptosis and terminating viral replication.

However, in most cases, normal cells do not immediately undergo apoptosis after being infected with adenovirus. The main reason is that wild-type adenovirus contains a protein that can inhibit p53 activation, namely E1b 55Kda protein, so wild-type adenovirus can also replicate in normal cells. When the adenovirus lacks the E1b 55 Kda protein, it cannot inhibit the activation of p53 when infecting normal cells. After p53 is activated, the cells will quickly undergo apoptosis, the adenovirus can no longer proliferate, and the infection will be terminated.

However, in tumor cells, p53 has mutated or been inactivated. Therefore, after viral infection, there is no p53 to be activated and the tumor cells will not die. Therefore, adenovirus lacking E1b 55Kda can proliferate in large numbers in tumor cells. Eventually, the tumor cells are lysed and die, and new viruses are released to infect other tumor cells to eliminate the tumor. Respiratory enterovirus (Reovirus) infection of humans is limited to the respiratory tract and gastrointestinal tract and is usually asymptomatic. After the virus infects, its early viral gene transcription can activate double-stranded RNA-dependent protein kinase (PKR), which can inhibit the transcription of other viral genes, thereby preventing the virus from effectively replicating. When Ras in the cell is in an activated state, it can inhibit the kinase, allowing the virus to proliferate and replicate. The Ras gene is an oncogene, and when it is abnormally activated, cancer may occur. Lee et al. from the University of Calgary in Canada used this virus to treat the SCID mouse model of human glioma with high Ras expression, which significantly reduced or eliminated the tumors in 65% to 80% of the mice. In in vitro experiments, it has the same therapeutic effect on other tumors with high Ras expression, such as breast cancer, prostate cancer and pancreatic cancer.