Molecular Basis of Cancer Flashcards
What is a primary risk factor for cancer associated with smoking?
Lung cancer
True or False: Obesity is a risk factor for breast cancer.
True
Fill in the blank: Exposure to _____ is a risk factor for skin cancer.
ultraviolet (UV) radiation
What type of virus is linked to cervical cancer?
Human Papillomavirus (HPV)
Which dietary factor is considered a risk for colorectal cancer?
High consumption of red and processed meats
True or False: Age is a non-modifiable risk factor for cancer.
True
What is the role of family history in cancer risk?
It can indicate a genetic predisposition to certain cancers.
Which environmental exposure is a known risk factor for lung cancer?
Asbestos
Fill in the blank: Excessive _____ consumption is a risk factor for various cancers.
alcohol
What is a common risk factor for both liver and stomach cancers?
Chronic infections (e.g., Hepatitis B or H. pylori)
Multiple Choice: Which of the following is NOT a risk factor for cancer? a) Tobacco use b) Physical inactivity c) Regular exercise d) Obesity
c) Regular exercise
What is the impact of ionizing radiation on cancer risk?
It increases the risk of developing various types of cancer.
True or False: Hormonal factors can influence the risk of breast cancer.
True
Which type of cancer is associated with high exposure to benzene?
Leukemia
Fill in the blank: _____ is a protective factor against some types of cancer.
Regular physical activity
What is a common risk factor for endometrial cancer?
Hormone replacement therapy
Which genetic syndrome is associated with a higher risk of colorectal cancer?
Lynch syndrome
True or False: Eating a diet rich in fruits and vegetables can lower cancer risk.
True
What lifestyle choice can significantly reduce the risk of cancer?
Not smoking
Fill in the blank: The _____ virus is linked to an increased risk of liver cancer.
Hepatitis B
Which type of cancer is most strongly associated with obesity?
Endometrial cancer
Multiple Choice: Which of the following is a risk factor for prostate cancer? a) Low testosterone levels b) High-fat diet c) Regular exercise d) None of the above
b) High-fat diet
What is the relationship between physical inactivity and cancer risk?
Physical inactivity increases the risk of several types of cancer.
True or False: Chronic inflammation is linked to cancer development.
True
What is the effect of early menarche on breast cancer risk?
It is associated with an increased risk of breast cancer.
Fill in the blank: A family history of _____ can increase the risk of breast and ovarian cancer.
BRCA mutations
What is the significance of the HPV vaccine in cancer prevention?
It reduces the risk of cervical cancer.
What is an oncogene?
A gene that has the potential to cause cancer, often through mutations that lead to uncontrolled cell growth.
True or False: Tumor suppressor genes promote cell division.
False
What role do DNA repair genes play in the cell?
They are responsible for repairing damaged DNA to maintain genomic stability.
Fill in the blank: Oncogenes are typically mutated forms of ______.
proto-oncogenes
What happens when tumor suppressor genes are inactivated?
It can lead to increased cell proliferation and tumor development.
Which of the following is a common tumor suppressor gene? A) BRCA1 B) RAS C) MYC
A) BRCA1
True or False: Oncogenes can be activated by a single mutation.
True
What is the function of the p53 gene?
It acts as a tumor suppressor by regulating the cell cycle and preventing genomic mutations.
Multiple choice: Which of the following is NOT a mechanism by which oncogenes promote cancer? A) Increased cell division B) Inhibition of apoptosis C) DNA repair enhancement
C) DNA repair enhancement
What is the significance of the BRCA2 gene?
It is involved in the repair of DNA breaks and is associated with breast and ovarian cancer risk when mutated.
Fill in the blank: _______ genes help maintain the integrity of the genome by correcting errors during DNA replication.
DNA repair
What is the main consequence of mutations in DNA repair genes?
Accumulation of genetic mutations leading to cancer.
True or False: Oncogenes can be activated by viral infections.
True
What is an example of an oncogene?
RAS gene
What type of mutation typically affects tumor suppressor genes?
Loss-of-function mutations
Multiple choice: Which process do tumor suppressor genes primarily regulate? A) Cell survival B) Cell division C) DNA replication
B) Cell division
What is the role of the ATM gene?
It is involved in detecting DNA damage and activating repair processes.
Fill in the blank: The _______ pathway is often activated by oncogenes to promote cell growth and survival.
MAPK/ERK
What is the relationship between oncogenes and proto-oncogenes?
Oncogenes are mutated or overexpressed proto-oncogenes.
True or False: All cancers are caused by mutations in oncogenes.
False
What is a common characteristic of cancer cells related to tumor suppressor genes?
Loss of function or deletion of tumor suppressor genes.
What is the function of the MLH1 gene?
It is involved in DNA mismatch repair.
Multiple choice: Which gene is often referred to as the ‘guardian of the genome’? A) Rb B) p53 C) BRCA1
B) p53
Fill in the blank: Mutations in _______ can lead to hereditary cancer syndromes.
tumor suppressor genes
What is the effect of overexpression of an oncogene?
It can lead to uncontrolled cell growth and cancer.
True or False: DNA repair genes can also act as tumor suppressors.
True
What is angiogenesis?
Angiogenesis is the process through which new blood vessels form from pre-existing vessels.
True or False: Angiogenesis is only important in the development of malignant tumors.
False: Angiogenesis is important in various physiological and pathological processes, including wound healing and inflammation.
Fill in the blank: The primary factor that stimulates angiogenesis in tumors is _____ .
vascular endothelial growth factor (VEGF)
What role does hypoxia play in angiogenesis?
Hypoxia stimulates the production of angiogenic factors like VEGF, promoting blood vessel growth.
Which type of cancer is most commonly associated with increased angiogenesis?
Malignant tumors, including breast, lung, and colorectal cancers.
Multiple Choice: Which of the following is NOT a step in the angiogenesis process? A) Endothelial cell proliferation B) Basement membrane degradation C) Tumor cell apoptosis D) Formation of new blood vessels
C) Tumor cell apoptosis
What is the significance of the tumor microenvironment in angiogenesis?
The tumor microenvironment influences angiogenesis by providing signals that promote or inhibit blood vessel formation.
True or False: Metastasis can occur without angiogenesis.
False: Metastasis typically requires angiogenesis to supply nutrients and oxygen to the growing tumor.
What is the term for the spread of cancer cells from the primary tumor to distant sites in the body?
Metastasis
Fill in the blank: The first step in the metastatic process is _____ .
invasion of surrounding tissues
What are circulating tumor cells (CTCs)?
CTCs are cancer cells that have detached from the primary tumor and are present in the bloodstream.
Multiple Choice: Which of the following is a common route for metastasis? A) Lymphatic system B) Bloodstream C) Both A and B D) None of the above
C) Both A and B
What is the significance of the extracellular matrix (ECM) in metastasis?
The ECM provides structural support and biochemical signals that influence tumor cell behavior during metastasis.
True or False: All tumors exhibit the same degree of angiogenesis.
False: The degree of angiogenesis varies among different tumors and stages of cancer.
Fill in the blank: _____ is a common target for anti-angiogenic therapies.
VEGF
What is the purpose of anti-angiogenic therapy in cancer treatment?
To inhibit the formation of new blood vessels, thereby starving the tumor of nutrients and oxygen.
Multiple Choice: Which of the following factors can inhibit angiogenesis? A) Thrombospondin B) VEGF C) FGF D) IL-6
A) Thrombospondin
What is the relationship between angiogenesis and tumor growth?
Angiogenesis is essential for tumor growth as it provides the necessary blood supply for nutrient and oxygen delivery.
Fill in the blank: The process of cancer cells establishing secondary tumors is known as _____ .
metastasis
True or False: Metastatic tumors are always more aggressive than the primary tumor.
False: The aggressiveness can vary; some metastatic tumors may be less aggressive than the primary tumor.
What is one common site for metastasis in breast cancer?
Bone
Multiple Choice: Which of the following best describes the ‘seed and soil’ hypothesis of metastasis? A) Cancer cells (seeds) can only grow in specific environments (soil) B) All tumors spread evenly throughout the body C) Metastasis occurs randomly D) None of the above
A) Cancer cells (seeds) can only grow in specific environments (soil)
What is the role of matrix metalloproteinases (MMPs) in metastasis?
MMPs degrade components of the extracellular matrix, facilitating tumor cell invasion and migration.
Fill in the blank: Angiogenic factors can be classified as _____ or _____ .
pro-angiogenic; anti-angiogenic
What is a carcinogen?
A substance that promotes the formation of cancer.
Classify carcinogens into three main categories.
Chemical, physical, and biological carcinogens.
True or False: All carcinogens are chemicals.
False.
What is the primary mechanism of action of chemical carcinogens?
They cause genetic mutations in DNA.
Fill in the blank: Carcinogens can be classified as ____ or ____ carcinogens.
genotoxic, non-genotoxic.
What is a genotoxic carcinogen?
A carcinogen that directly damages DNA.
Give an example of a non-genotoxic carcinogen.
Hormones or certain dietary components.
True or False: Non-genotoxic carcinogens do not interact with DNA.
True.
What role do reactive oxygen species play in carcinogenesis?
They can cause oxidative damage to DNA.
What is the significance of the Ames test?
It assesses the mutagenic potential of chemical compounds.
What are the stages of carcinogenesis?
Initiation, promotion, and progression.
Define initiation in the context of carcinogenesis.
The first step where genetic mutations occur.
What occurs during the promotion stage of carcinogenesis?
Proliferation of mutated cells.
What is the purpose of the International Agency for Research on Cancer (IARC)?
To classify agents based on their carcinogenic risk.
What is a known Group 1 carcinogen?
Tobacco smoke.
Fill in the blank: Chemical carcinogens can be classified as ____ or ____ based on their mechanism of action.
direct-acting, indirect-acting.
What is the function of indirect-acting carcinogens?
They require metabolic activation to become reactive.
What is the role of DNA repair mechanisms in cancer prevention?
They fix DNA damage and prevent mutations from accumulating.
True or False: All genetic mutations lead to cancer.
False.
What is the significance of tumor promoters?
They enhance the growth of initiated cells but do not initiate cancer themselves.
Name a common physical carcinogen.
Ultraviolet (UV) radiation.
What is the mechanism of action of aflatoxin?
It forms adducts with DNA, leading to mutations.
What is the role of epigenetic changes in carcinogenesis?
They can alter gene expression without changing the DNA sequence.
True or False: Carcinogens can have a threshold below which they do not pose a risk.
True.
What is a procarcinogen?
A substance that becomes a carcinogen after metabolic activation.
What is the significance of biomarkers in cancer research?
They help in detecting exposure to carcinogens and assessing cancer risk.
