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.
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.
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.
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.
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.
At present, cancer treatment methods include surgical treatment, radiotherapy, chemotherapy, biotherapy, immunotherapy and targeted therapy.
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.
It is only effective for patients who carry the specific targeted gene mutation corresponding to the targeted medicine.
For patients who suffer from different kinds of cancer, corresponding molecular detection should be conducted to see if there is gene mutation which makes it meaningful to use targeted medicine.
Traditional methods for molecular detection include Sanger sequencing, qPCR, ARMs-PCR, FISH and IHC. Types of gene mutation include gene point mutation, insertion, deletion, copy number mutation and fusion. Sample amount, gene number, number of mutation spots and mutation types detected by traditional detection methods at one time are limited while the latest next generation sequencing technology can well solve these problems. The method has the characteristics of high-flux detection, multi-gene detection, multi-spot detection and multi mutation type detection, realizing parallel detection of multiple medicine targeted genes and multiple mutation forms.
Forms of samples accepted by Burning Rock Dx include: pathological section (white section), hydrothorax and peripheral blood. When collecting blood, you should use specialized Streck blood collection tubes provided by Burning Rock Dx. For specific preservation and delivery requirements, you should communicate with local sample recipients.
Tumors are caused by two kinds of factors: one is acquired factor and the other is congenital hereditary factor. Tumors caused by congenital hereditary factor are called hereditary tumors. For example, if there are several generations of families suffering from cancer successively in a family, it is probably a kind of family hereditary tumor.
Tumor is a kind of genetic diseases, and causes of all tumors are related to abnormal change in genes. Hereditary tumors are caused by abnormal or defective genes carried by patients congenitally. These genes that may cause hereditary tumors if defection appears are called tumor susceptibility genes.
Gene detection refers to the process of analyzing and detecting a subject’s gene information by specialized technical means after obtaining a trace amount of sample (such as a small amount of peripheral blood) of the person to be detected. Moreover, gene detection for hereditary tumors can realize screening to see if there are abnormal mutations in hereditary tumor susceptibility genes carried by the subject.
Through gene detection for hereditary tumors, we can see if there are abnormal mutations in hereditary tumor susceptibility genes carried by the subject so as to see if the subject’s genes are in normal condition, how much the risk of suffering from some hereditary tumors is, and other information. By gene detection for hereditary tumors, we can find hidden dangers which threats health in the circumstance of no tumors yet so as to alert in advance, more specifically improve living environment and living habits, enhance prevention and monitoring, and thus guarantee healthy life in the future.
It doesn't mean that someone will certainly suffer from hereditary tumor if defection of hereditary tumor genes is detected, but the suffering risk is much higher than that of those people who carry normal genes. For example, Angelina Jolie, a famous Hollywood movie star, was detected that there was a mutation in her BRCA1 gene; her risk of suffering from hereditary breast cancer when she is 50 years old is up to 56-87% while that of normal female is only 7%.
People who have a family history of tumors should carry out gene detection for hereditary tumors as soon as possible so as to know their own risks of suffering from tumors and take specific precautions at an early date. For patients who have suffered from common tumors such as breast cancer and colorectal cancer: it should be identified to see if it is hereditary breast cancer so as to provide specific treatment and provide important hints for their kinsfolk. There is a 50% probability for patients who suffer from hereditary tumors to pass defective genes on to their own children. It doesn't mean that the risk only exists for people who have a family history of hereditary tumors. Even if there is no family history, offspring is also likely to suffer from hereditary tumors if there are mutations in germ cells. Therefore, gene detection for hereditary tumors is also suitable for people who concern with their health.
First of all, you should adjust your mindset and actively face with the result. Then, you should consult your doctor about different tumor risks to obtain specific and specialized risk management suggestions, thus knowing, preventing, discovering and treating tumors at an early date. If gene mutation is detected and it is pointed out that there is a high risk of suffering from hereditary tumor, it will bring about great mental stress, which may lead to a negative impact on the subject's life. Then, what's the meaning of detection? First of all, you should know that no matter gene detection for hereditary tumors is carried out or not, defective genes carried by yourself still exist and the suffering risk is also the same. However, after knowing there are defective genes, you can immediately take specific measures, such as specialized risk control plans for breast cancer, colorectal cancer or other corresponding cancers, adjustment of living habits, and regular inspection. If you can prevent scientifically and accept early diagnosis, early or ultra early treatment of cancer can be achieved, and the risk of suffering from cancer may even be directly and dramatically reduced by preventive excision or other methods. If you don't know you carry the defective genes, it is very difficult for you to specifically prevent or accept early diagnosis. If cancer is discovered when it has developed to the middle and terminal stage, the best time for treatment has been missed.
No. Mutations in tumor susceptibility genes can dramatically increase the risk of suffering from some hereditary tumors, and people who carry normal genes also have the risks, but their risks are much lower relatively. Whenever it is, healthy lifestyle and healthy environment are necessary.
Since genes related to hereditary tumors are congenital and inherent, one time of gene detection for hereditary tumors is referable throughout your life. Certainly, with continuous development of scientific research, if more new hereditary tumor susceptibility genes are found after several years, you can detect again to obtain more information.
After death or apoptosis of tumor cells, a part of DNA will be released into blood stream. These DNA carries gene mutations which are related to tumors. Liquid biopsy is to obtain information of mutation related to tumor in a patient's body by blood drawing so as to provide relevant guidance for treatment of the patient but not bring more physical harms to the patient.
Detection of tissue samples obtained by surgery or puncture is very harmful to a patient's body. However, for liquid biopsy, detection can be carried out only by drawing one tube of blood, which will not cause much harm to the patient. Thus, sampling and detection can be conducted repeatedly, realizing dynamic monitoring of the patient's condition and providing more references for clinical treatment.
Our technology takes a leading position in China. By adopting the most advanced detection technology in the world, we carried out over 10,000 times of detection covering every spot on 168 genes related to lung cancer and 63 genes related to other tumors without missing detection of any potential mutations. At present, we have closely cooperated with many domestic Grade-A hospitals.
We mainly detect two kinds of genes: one is genes related to tumor medicine, which are recognized at home and abroad at present, and the other is genes closely related to occurrence of tumors. The former is closely related to guiding medicine use of the patients, and the latter is closely related to monitoring treatment effects after recovery of the patients.
Liquid biopsy mainly includes three steps: 1. drawing 10 ml of peripheral blood of a patient; 2. obtaining ctDNA in the blood by DNA extraction technology, obtaining sequencing data by high-flux sequencing technology, and then interpreting sequencing data by applying bioinformatics to obtain information of mutation on genes related to tumors; 3. issuing a clinical detection report according to the genetic mutation information as a reference and basis for targeted therapy of the patient.
Liquid biopsy is to detect peripheral blood of patients, which is non-invasive for the patients and is suitable for preliminary diagnosis and relapse monitoring of patients under terminal stage; tissue biopsy is a very mature detection technology, which detects tissue samples of patients, but it is invasive and harmful to the patients when obtaining tissue samples no matter by surgery or by puncture.
The liquid biopsy is suitable for patients in the stage of IIIB-IV. At present, sensitivity of our liquid biopsy for patients under terminals stage of NSCLC is 85%, so liquid biopsy is suitable. However, in early stage, sensitivity of tissue detection is higher, so tissue detection is much suitable for patients in early stage.
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.
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.