Cancer, also known as "malignant tumor," is a group of diseases characterized by uncontrolled proliferation and spread of abnormal cells that may invade other parts of the body and cause cancer cells to spread and metastasize. Usually, we name cancer after the original location of the cancer cell, for example, a cancer that is in the lung is called lung cancer, a cancer that is in the pancreas is called pancreatic cancer, and a cancer that is in the liver is called liver cancer.
Fig 1. Cancer cells and normal cells
Benign and malignant tumors
Cancer can be divided into two types, benign and malignant. Benign tumors are usually well differentiated, slow growing, without the ability to infiltrate or metastasize, and do little harm to the body. Malignancies, on the other hand, are usually aggressive, with the absence of contact inhibition leading to unlimited growth and the possibility of local infiltration and distant metastases (lymphatic and blood metastases) that destroy normal cells and produce lesions.
Fig.2 Different types of tumor cells
Cancer is a cell mutation caused by a mutated gene that accumulates to a point that causes uncontrolled cell proliferation and harms other cells. According to modern medical research, there are about 200 kinds of genes related to cancer, and each kind of cancer is caused by mutations in more than 10 kinds of genes. Cancer can take more than a decade to develop from a genetic mutation to symptoms.
There are four stages of cancer, commonly known as the first and second stages of cancer, which also have the highest cure rates. These two stages are usually determined by the size of the tumor. The third stage is when the tumor has become large and the tumor cells can be detected in the blood, but has not yet successfully metastasized. By stage four, the cancer has successfully metastasized.
Metastasis: this stage is the dividing point between malignant and benign tumors.
Classification of cancer
According to the different parts of the body where cancer occurs, cancer also has different names. The areas where cancer occurs in the human body include:
Respiratory, digestive, urinary, circulatory, motor, reproductive, and other organcancers.
1. Respiratory cancer mainly includes: lung cancer, nasopharyngeal cancer and laryngeal cancer.
- Lung cancer: lung cancer is the most common lung cancer, the vast majority of lung cancer originated in the bronchial mucosa epithelial, so called bronchial lung cancer. Surgical resection is the first choice for the treatment of lung cancer. Primary cancer is confined to the bronchi and lung, and no distant metastasis or lymph node metastasis has occurred, the 5-year survival rate after surgery can reach more than 50%.
- Nasopharyngeal carcinoma: nasopharyngeal carcinoma refers to the malignant tumor occurring at the top of nasopharyngeal cavity and lateral wall. Nasopharyngeal carcinoma has obvious epidemiological characteristics. Men are the majority, about twice as many as women.
- Laryngeal carcinoma: laryngeal carcinoma is a malignant tumor originated from the epithelial tissue of laryngeal mucosa. The most common laryngeal carcinoma is laryngeal squamous cell carcinoma, which is more common in middle-aged and elderly men.
2. Cancers of the digestive system mainly include: stomach cancer, liver cancer, esophageal cancer, bowel cancer, pancreatic cancer, gallbladder cancer and oral cancer.
- Gastric cancer: malignant tumor gastric cancer originated from the most superficial layer of gastric wall mucosal epithelial cells, can occur in various parts of the stomach, can invade the stomach wall of different depth and breadth. Cancer foci is confined inside mucous membrane or submucous membrane is called early gastric cancer, invade musculature layer to be deep or the person that has metastasis to gastric outside the area is called advanced gastric cancer.
- Hepatocellular carcinoma: hepatocellular carcinoma refers to malignant tumors that occur in the liver, including primary liver cancer and metastatic liver cancer. The incidence of a disease of liver cancer and mortality are very tall, initial symptom is not apparent, can do not have any symptom or sign, basically show for liver pain, lack of power, angular, icteric, ascites to wait for a symptom commonly.
- Esophagus cancer: esophagus cancer is called esophagus cancer again, it is the malignant tumor that points to esophagus epithelial source, basically show when swallowing food, produce choked feeling, foreign body feeling, after sternum ache or apparent dysphagia. If metastasis or invasion of adjacent organs occurs, pain and corresponding discomfort of the organs involved may occur.
- Bowel cancer: it is the common malignant tumor in gastrointestinal tract, the incidence rate is second only to gastric and esophageal cancer, is the most common part of colorectal cancer (accounting for about 60%). Bowel cancer initial stage so that blood is given priority to, it is defecate habit changes next, defecate not to feel, tenesmus is heavy wait, still cause obstruction phenomenon extremely easily in addition, produce bowel stimulation symptom to wait.
- Pancreatic cancer: pancreatic cancer is a highly malignant gastrointestinal malignancy that is difficult to diagnose and treat. Its morbidity and mortality have increased significantly in recent years. 5-year survival rate <1% is one of the worst prognosis of malignant tumors.
- Gallbladder cancer: gallbladder cancer is a malignant tumor originated from the epithelial cells of gallbladder mucosa, which is the most common malignant tumor in the biliary system, accounting for more than 70% of biliary malignant tumors. The location of the disease is located in the gallbladder, which varies according to the anatomical location of the tumor originating from the gallbladder, including the bottom of the gallbladder, body, neck and gallbladder duct. The disease is more common at the base of gallbladder, neck and body.
- Oral cancer: oral cancer is a group of malignant tumors that occur in the oral cavity. In clinical practice, oral cancer includes gum cancer, tongue cancer, soft palate cancer, jaw bone cancer, oral floor cancer, oropharyngeal cancer, salivary gland cancer, lip cancer, and maxillary sinus cancer, as well as cancer occurring in the skin and mucous membrane of the face. Oral cancer is one of the most common malignancies of the head and neck.
3. Urinary system cancer mainly includes: kidney cancer, bladder cancer, prostate cancer and urethral cancer.
- Renal cancer: it is also known as renal cell carcinoma, renal adenocarcinoma, originated in the urinary tubule epithelium. Kidney cancer accounts for about 80 to 90 percent of adult malignancies and is the most common form of kidney cancer in adults. The cause of kidney cancer is unknown. Genetic factors, smoking, obesity, hypertension and antihypertensive therapy have been identified, and avoiding smoking and obesity are important methods to prevent the occurrence of renal cancer.
- Bladder cancer: malignant overgrowth of cells in the bladder. The most common overgrowth occurs in the bladder cavity, the mucosa lining the bladder. The surface of the empty viscera in the body is usually composed of epithelial cells, and each organ has its own kind of epithelial cells. The mucosal epithelial cells of the bladder are called urothelial cells, and the cancers that result from them are called urothelial carcinomas, which account for 90% to 95% of all bladder cancers and are the most common type of bladder cancer.
- Prostate cancer: prostate cancer is a malignant epithelial tumor that occurs in the prostate gland. The incidence of prostate cancer is strongly related to genetic factors, as well as sexual activity and dietary habits. Men who were more sexually active had an increased risk of prostate cancer, and a high-fat diet was linked to the disease.
- Urethral carcinoma: urethral carcinoma belongs to urethral epithelial tumor, which is relatively rare in clinical practice. The cause of urethral cancer is not clear, but it has nothing to do with the possibility of the occurrence of urethral caruncle. The white spots of urethra may be precancerous lesions. The early stage of urethral cancer is similar to the caruncle, polyp and papilloma of urethra.
4. Blood circulatory system cancer basically includes: leukaemia, lymphatic cancer, hemangioma.
- Leukemia: leukemia is a kind of hematopoietic stem cell malignant clonal disease. Clonal leukemia cells proliferate and accumulate in bone marrow and other hematopoietic tissues, infiltrate other non-hematopoietic tissues and organs, and inhibit normal hematopoietic function due to the mechanism of uncontrolled proliferation, differentiation disorder and blocked apoptosis. Clinical manifestations include anemia, bleeding, infectious fever, enlarged liver, spleen, lymph nodes, and bone pain.
- Lymphatic cancer: lymphoma is a malignant tumor originated from the lymphatic hematopoietic system, mainly manifested as painless lymph node enlargement, hepatosplenomegaly, all tissues and organs of the body can be affected, accompanied by fever, night sweats, emaciation, itching and other systemic symptoms.
- Hemangioma: hemangioma is by embryonic period hemangioblast cell proliferation and formation of common skin and soft tissue in the congenital benign tumor or vascular malformation, more in the birth of the baby or shortly after birth. Residual embryonic vascular cells and active endothelioid germ invade into adjacent tissues, forming endothelial spline cords, which are connected with the remaining blood vessels and form hemangioma. The internal blood vessels in the tumor form their own system and are not connected with the surrounding blood vessels. Hemangioma can occur everywhere in the body, hemangioma occurs in the oral and maxillofacial probability is larger.
5. Cancers of the sports system can be divided into bone cancer, tenosynoblastoma and leiomyoma, etc.
- Bone cancer: a bone tumor is one that develops in the bone or its associated tissues. There are benign and malignant. Malignant bone tumor, is often referred to as bone cancer. Malignant bone tumors are classified as primary and secondary. Malignant tumors from other tissues or organs in the body metastasize to bone through the blood circulation and lymphatic system as secondary malignant bone tumors.
- Ganglion sheath tumor: a giant cell tumor of the tendon sheath is a firm, painless mass that occurs in the fingers and hands. The giant cell tumor of tendon sheath is lobulated with dense, transparent collagen surrounding the lobules.
- Leiomyoma: a leiomyoma is a benign tumor of skin smooth muscle cells. Can be produced by smooth muscle of hemal smooth muscle, stand hair muscle and the smooth muscle of breast or scrotum and come, disease may be concerned with heredity.
6. Cancers of the reproductive system include: cervical cancer, uterine cancer, ovarian cancer and testicular cancer.
- Cervical cancer: cervical cancer is the most common gynecologic malignant tumor. The incidence of carcinoma in situ is 30 ~ 35 years old, and the incidence of invasive carcinoma is 45 ~ 55 years old.
- Uterine cancer: uterine cancer actually refers to endometrial cancer, often occurring after menopause. In recent years, the incidence of the disease is on the rise worldwide. It can spread to many parts of the body: down from the uterus to the cervical canal, up from the fallopian tubes to the ovaries; It can also infiltrate into tissue around the uterus; Or by the lymphatic system and blood circulation away from the uterus.
- Ovarian cancer: ovarian malignant tumor is one of the most common malignant tumors of female reproductive organs. The mortality rate of ovarian epithelial cancer is the first among all kinds of gynecological tumors, which poses a serious threat to women's life.
- Testicular cancer: testicular tumor is one of the common tumors in urology, testicular tumors are divided into primary and secondary, the vast majority are primary, secondary is extremely rare. Almost all testicular tumors are malignant, and their etiology is still unknown. Among them, cryptorchidism is the most closely related, and the incidence of tumor in cryptorchidism is 10 ~ 14 times higher than normal.
Protein is the main working substance of the human body. It participates in almost every process of cells. Different types of molecules, such as sugars, can be added to proteins to change their action or position, becoming glycoproteins that provide recognition on the cell surface. At the same time, this process may also play a role in cancer. Some proteins that modify, promote and recognize functions are closely related to the metastasis and spread of tumor cells.
In fact, tumor cells that contain certain sugar modifications are more likely to spread in the body. For example, a specific combination of glycoproteins called t-antigens is rarely present in healthy adult cells; But it is often present in metastatic cancer cells, which leave the site of their growth and invade another tissue to form a new tumor. But until now, researchers have not known whether t-antigens promote this process or simply appear on these cells.
Fig.3 Cancer cells and their surface proteins
Most of the proteins present in cancer cells are important for cancer cells and the immune system. Some proteins are produced only in cancer cells and act mainly like cytokines to promote proliferation and spread of cancer cells. Usually, such protein molecules are overexpressed at the sites where cancer cells have metastasized. Some proteins are involved in the body's immune function, suppressing the effects of immune cells and reducing the risk that cancer cells will be recognized by the body's immune system. Till now, there are over 120 types of cancer and the common cancer includes breast cancer, hepatoma, skin cancer, lung cancer, colon cancer, gastrointestinal cancer, prostate cancer, leukemia and lymphoma. As a primary manufacturer of recombinant proteins, Creative Biomart provides recombinant proteins of several sources, grades and formulations for cancer research applications.
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