Cancer is malignant tumor, a group of diseases which have some common features. In addition to constant proliferation, cancer cells can also locally invade surrounding normal tissue and even transfer to other parts of the body via blood circulation system or lymphatic system. At present, over 100 kinds of cancer have been known.
What causes cancer?
Causes of cancer can be ascribed to accumulation of DNA mutations. Accumulation of mutations results in massive expression of proteins that promote growth of cells, and destroying the function of tumor suppressor genes, which makes cell cycle control abnormal. Substances that cause mutations are called mutagenic agents, wherein the mutagenic agents that can cause cancer are called carcinogenic substances. Different carcinogenic substances can cause different kinds of cancer. For example, chemical substances inhaled when smoking can cause lung cancer; prolonged exposure to ultraviolet radiation from the sun can lead to melanoma and other skin malignancies. Besides, many kinds of cancer originate from virus infection. Viruses related to cancer mainly include hepatitis B virus, EB virus and human papillomavirus.
What is gene?
A gene is a DNA sequence that carries hereditary information and a basic hereditary unit that controls characters, that is, a functional DNA sequence. Genes express the hereditary information they carried by guiding synthesis of proteins, and thus control expression of individuals’ characters (differences). Each person has 20,000 to 25,000 genes.
What are tumor driving genes?
If there is a change (mutation, amplification, and rearrangement, etc.) in some certain important genes that regulate and control growth of cells, leading to activation of proto-oncogenes and inactivation of cancer suppressor genes, these changed genes that convert normal cells into tumor cells are called tumor driving genes.
What are common tumor driving genes?
Tumor driving genes of different kinds of cancer are not necessarily the same. Taking non-small cell lung cancer as an example, its common tumor driving genes include EGFR, ALK, HER2, MET, RET, ROS1, BRAF and KRAS.
What is NGS technology?
NGS technology is the abbreviation of next generation sequencing technology, and is a definition relative to the first generation sequencing technology. DNA sequencing refers to analysis of base sequence of a specific DNA fragment by particular technical means, that is, arrangement mode of Adenine (A), Guanine (G), Cytosine (C) and Thymine (T). Due to its capability of sequencing for millions of DNA fragments simultaneously, the next generation sequencing technology is also called high-flux sequencing technology.
What are the advantages of NGS technology comparing with traditional molecular diagnosis methods?
For traditional molecular diagnosis methods (such as PCR, FISH and IHC), mutation, fusion, amplification, insertion, deletion and other changes of multiple genes can not be detected simultaneously. At present, parallel detection of multiple genes and multiple mutation forms can be carried out only by NGS technology. NGS technology helps patients detect if mutation occurs or not in all genes to which target medicine is used with the least cost and within the shortest time, thus striving for as many chances of targeted therapy as possible for patients.
What are the methods for treatment of cancer?
At present, cancer treatment methods include surgical treatment, radiotherapy, chemotherapy, biotherapy, immunotherapy and targeted therapy.
Which is the best method to treat cancer?
Each kind of treatment method has its own advantages and disadvantages. Similarly, treatment effects for different kinds of cancer are not the same. Thus, the principle of combining multidisciplinary synthetic therapy with “individualized treatment” should be adopted, that is, adopting the mode of multidisciplinary synthetic therapy according to a patient’s body state, histopathological type and molecular typing of tumor, invasion scope and development trend, and reasonably applying various treatment means in a planned way to prolong the patient’s life time, increase survival rate, control tumor progression and improve the patient’s living quality to the greatest extent.
What kind of patients can take targeted medicine?
is only effective for patients who carry the specific targeted gene mutation corresponding to the targeted medicine.