Econ 101 1st Edition Lecture 6Outline of Last LectureCells Organization of Cells II. The Cell Cycle The Cell Checkpoints III. Growth Factors IV. Cell Function and Cancer Characteristics of a Normal Cell and Cancer Cell V. Protein Production V. Genetic Code VII.DNA ReplicationOutline of Current LectureI. CancerII. How Does Cancer DevelopIII. New Tissue GroupsIV. Tumor DevelopmentProperties of Tumors V. Tumor Grade and Cancer Survival VI. Tumor Stage VII. Different Kinds of Cancer VIII.Cancer Cases and Cancer Deaths IX. Five Year Survival Rates X. Factors Influencing Survival RatesCurrent LectureThese notes represent a detailed interpretation of the professor’s lecture. GradeBuddy is best used as a supplement to your own notes, not as a substitute.Mastectomy specimen: When they take out a portion of the breast that is cancerousHippocrates is credited with being the first to recognize the difference between benign and malignant tumorsSwollen blood vessels around the malignant tumors reminded him of crab claws— disease is called quirkiness Cancer is a term that refers to over 100 diseases that share two common characteristics:An uncontrolled growth of cellsThe ability to invade and damage normal tissues either locally or distant sites in the body They start infiltrating the normal tissue around them Cell or a bunch of cells will break off from the major tissue from the body and travel to distant locations (make a new tumor) How does Cancer Develop?Cancer develops when cells in a part of the body begin to grow out of control (tumor) When they grow out of control— DNA damage 3 gene families: oncogenes (onco= cancer) genes whose protein products actually promote cancer, DNA repair genes, and tumor suppressor genes (proteins responsible for surveying a cell— induce apoptosis) Damaged genes can be inherited (25%), or due to environmental factors (75%) In cancer cells, the damaged DNA is not repaired and the damaged cell does not undergo apoptosis— instead the cell begins to divide uncontrollably— results in tumorUncontrolled growth can have different types of manifestationHyperplasia: green: stem dividing so they can give them to daughter cells Neoplasia: Normal cells when they touch each other stop growing— cancercells start growing over each other— infiltrate surrounding tissues Neoplasm: abnormal tissue growth in which cells proliferate in an uncontrolled, autonomous fashion leading to a tumor, not listening to stop growing signals coming from other cellsTumor: swelling caused by fluid build up or cell accumulation, doesn’t mean it’s cancer• Can be benign or malignantStem cells- divide (dry skin— scraped off, has to be replace) skin constantly replacing itselfWhen they divide one of the cells stay basal cell and the other starts to matureAs it matures it becomes (square cells) squamous cells Shred off dead cells Never become fully mature squamous cells• Daughter cells could have inherited a mutation or gotten it from the environmentProperties of Malignant and Benign TumorsBenignMalignantGrowth Patternlocal growth onlyspreads by invasion andmetastasis (malignant)Life threateningrarelyoftenGrowth Rateusuallymay be rapidCancerous cells (big nucleus)— replication of DNA messed up• Cancerous cells divide quickly•Differentiation: when the cell gains a specific job (cell growing up and developing what it is supposed to be)Benign can still perform the functions If it is well defined- encapsulated- there is a covering: that helps define whattype of tumor Hides tumor (cancer) from the immune system when it becomes malignant it breaks off Normal and Malignant Specimen Left: organized few nuclei• Healthy base of lamina (support system for tissues)Right: less organized; not well formed- strangely shaped- a lot more of nuclei• Indicates the likelihood of cancerTumor Grade and Cancer Survival (tells you how bad it is once you get to diagnosis)If a tumor is suspected to be malignant, a doctor removes a sample of tissueor the entire tumor in a procedure (biopsy)Tumor Grade: based on the microscopic appearance of cancer cells and is associated with five year survival rates 5 year survival: how many people at the same grade of tumor that was diagnosed are alive 5 years later— individual cancers have differed survival rates Guidelines for Grading TumorsGradeDescriptionGXgrade cannot be assessedG1well differentiated (low grade)G2moderately differentiated (intermediate grade)G3poorly differentiated (high grade)G4undifferentiated (high grade)Tumor Stage: how large the tumor has grown and how far it has spread•Where is the location of the primary tumor?— Where did it begin, did it metastasized (it has spread to other organs)?— Has it spread to the lymph node?•Tumor gets bigger throughout stages— staging can predict 5 year survival rates by comparing to other people at the same stageTumor Stage and Lymph Node Involvement:Primary tumor:lymph node closest to the tumor (sentinel nodes)•Stage and Size work together•Infiltrate into tissue— blood vessels starting to grow into stage— metastasize growingDifferent Kinds of Cancer: transition cells move fast•Leukemia: type of cancer of the blood or bone marrow characterized by an abnormal increase of immature white blood cells but no tumor forms-White blood cells (cancerous) floating around•Lymphoma: is a type of blood cancer that occurs when B or T cells divide faster than or live longer than normal. Lymphoma may develop in the lymphnodes, spleen, bonemarrow, blood, or other organ and eventually they form a tumor- Lymphoma: abnormal so don’t do a good job with the immune systemThe majority of cancers are carcinomas (85%) (cancers that begin in the skin or in tissues that line or cover body organs)Types of Carcinomas:squamous cells: line different parts of the body (mouth, esophagus, lungs) adeno cells: lining on all the glands in the body (stomach, ovaries, kidneys, prostate) transitional cells: only found in the lining of the bladder and parts of the urinary system basal cells: found in one of the layers in the skin Relative Frequencies of Cancer Cases and Cancer Deaths:There’s a disconnect between what’s being diagnosed each year versus what the people die from• 50% skin cancer cases; however, death very low (slow growing, almost never invade and metastasize)— biggest death caused by lung cancer (smoking)Five Year Survival Rates: how bad are the different types of cancer in comparison to
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