Question

Free Response/Short Answer Questions - For question 27 and 28, write full and complete answers to each of the questions (40 points total, 20 points each question). 27. Questions regarding cancer, anti cancer drug design, functional group chemistry, thermodynamics. water, non-covalent interactions and ionization. a. How have cancers usually been classified? What is a newly developed cancer classification? b. What are key attributes of anti-cancer drugs and of their targets? c. How do C, H, O and N differ with regard to valence and electronegativity? How does this affect the properties of the covalent bond and functional groups that they form? lero d. What does AG tell you about the reactants and products of a chemical reaction? What else do you need to know to determine if a chemical reaction is favorable in a cell?

Answer 1

Cancers are classified in two ways: by the type of tissue in which the cancer originates (histological type) and by primary site,or the location in the body where the cancer first developed. This section introduces you to the first method: cancer classification based on histological type. From a histological standpoint there are hundreds of different cancers, which are grouped into six major categories:

Carcinoma
Sarcoma
Myeloma
Leukemia
Lymphoma
Mixed Types
Carcinoma
Carcinoma refers to a malignant neoplasm of epithelial origin or cancer of the internal or external lining of the body. Carcinomas, malignancies of epithelial tissue, account for 80 to 90 percent of all cancer cases.

Epithelial tissue is found throughout the body. It is present in the skin, as well as the covering and lining of organs and internal passageways, such as the gastrointestinal tract.

Carcinomas are divided into two major subtypes: adenocarcinoma, which develops in an organ or gland, and squamous cell carcinoma, which originates in the squamous epithelium.

Adenocarcinomas generally occur in mucus membranes and are first seen as a thickened plaque-like white mucosa. They often spread easily through the soft tissue where they occur. Squamous cell carcinomas occur in many areas of the body.

Most carcinomas affect organs or glands capable of secretion, such as the breasts, which produce milk, or the lungs, which secrete mucus, or colon or prostate or bladder.

Sarcoma
Sarcoma refers to cancer that originates in supportive and connective tissues such as bones, tendons, cartilage, muscle, and fat. Generally occurring in young adults, the most common sarcoma often develops as a painful mass on the bone. Sarcoma tumors usually resemble the tissue in which they grow.

Examples of sarcomas are:

Osteosarcoma or osteogenic sarcoma (bone)
Chondrosarcoma (cartilage)
Leiomyosarcoma (smooth muscle)
Rhabdomyosarcoma (skeletal muscle)
Mesothelial sarcoma or mesothelioma (membranous lining of body cavities)
Fibrosarcoma (fibrous tissue)
Angiosarcoma or hemangioendothelioma (blood vessels)
Liposarcoma (adipose tissue)
Glioma or astrocytoma (neurogenic connective tissue found in the brain)
Myxosarcoma (primitive embryonic connective tissue)
Mesenchymous or mixed mesodermal tumor (mixed connective tissue types)
Myeloma
Myeloma is cancer that originates in the plasma cells of bone marrow. The plasma cells produce some of the proteins found in blood.

Leukemia
Leukemias ("liquid cancers" or "blood cancers") are cancers of the bone marrow (the site of blood cell production). The word leukemia means "white blood" in Greek.
The disease is often associated with the overproduction of immature white blood cells. These immature white blood cells do not perform as well as they should, therefore the patient is often prone to infection. Leukemia also affects red blood cells and can cause poor blood clotting and fatigue due to anemia. Examples of leukemia include:

Myelogenous or granulocytic leukemia (malignancy of the myeloid and granulocytic white blood cell series)
Lymphatic, lymphocytic, or lymphoblastic leukemia (malignancy of the lymphoid and lymphocytic blood cell series)
Polycythemia vera or erythremia (malignancy of various blood cell products, but with red cells predominating)
Lymphoma
Lymphomas develop in the glands or nodes of the lymphatic system, a network of vessels, nodes, and organs (specifically the spleen, tonsils, and thymus) that
purify bodily fluids and produce infection-fighting white blood cells, or lymphocytes. Unlike the leukemias which are sometimes called "liquid cancers," lymphomas are "solid cancers." Lymphomas may also occur in specific organs such as the stomach, breast or brain. These lymphomas are referred to as extranodal lymphomas.
The lymphomas are subclassified into two categories: Hodgkin lymphoma and Non-Hodgkin lymphoma. The presence of Reed-Sternberg cells in Hodgkin lymphoma diagnostically distinguishes Hodgkin lymphoma from Non-Hodgkin lymphoma.

Mixed Types
The type components may be within one category or from different categories. Some examples are:

adenosquamous carcinoma
mixed mesodermal tumor
carcinosarcoma
teratocarcinoma

b.Anticancer drug, also called antineoplastic drug, any drug that is effective in the treatment of malignant, or cancerous, disease. There are several major classes of anticancer drugs; these include alkylating agents, antimetabolites, natural products, and hormones. In addition, there are a number of drugs that do not fall within those classes but that demonstrate anticancer activity and thus are used in the treatment of malignant disease. The term chemotherapy frequently is equated with the use of anticancer drugs, although it more accurately refers to the use of chemical compounds to treat disease generally.

Targeted therapy is a cancer treatment that uses drugs. But it is different from traditional chemotherapy, which also uses drugs to treat cancer. Targeted therapy works by targeting the cancer’s specific genes, proteins, or the tissue environment that contributes to cancer growth and survival. These genes and proteins are found in cancer cells or in cells related to cancer growth, like blood vessel cells.

Doctors often use targeted therapy with chemotherapy and other treatments. The U.S. Food and Drug Administration (FDA) has approved targeted therapies for many types of cancer. Scientists are also testing drugs for new cancer targets.

Types of targeted therapy

There are several types of targeted therapy:

Monoclonal antibodies. Drugs called “monoclonal antibodies” block a specific target on the outside of cancer cells and/or the target might be in the area around the cancer. These drugs work like a plastic cover you put in an electric socket. The plug keeps electricity from flowing out of the socket.Monoclonal antibodies can also send toxic substances directly to cancer cells. For example, they can help chemotherapy and radiation therapy get to cancer cells better. You usually get these drugs injected into a vein, or "intravenously" (IV)Small-molecule drugs. Drugs called “small-molecule drugs”can block the process that helps cancer cells multiply and spread. These drugs are usually taken as pills. Angiogenesis inhibitors are an example of this type of targeted therapy. These drugs keep tissue around the tumor from making blood vessels. Angiogenesis is the name for making new blood vessels. A tumor needs blood vessels to bring it nutrients. The nutrients help it grow and spread. Anti-angiogenesis therapies starve the tumor by keeping new blood vessels from forming.

c.Carbon,hydrogen,oxygen,nitrogen

Nitrogen – (5 Valence electron) is ubiquitous it’s everywhere around us. Nitrogen has 5-valance electron meaning it’s highly reactive. Nitrogen is in a gas form. Once an atom has like nitrogen has reacted it is really hard to separate. The more reactive a substance is more stronger it is to break and separate.

Carbon – (4 valence electron) is versatile, which means it reacts with many things, it’s the main property that’s makes it able to stick to anything.

Hydrogen – (1 Valence Electron) The most reactive substance in the universeThere is nothing smaller than a hydrogen ion. Hydrogen is really just a proton and an electron. (Best for supplying energy)

Oxygen – (6 valence electron) the atom is ubiquitous. Alcohol in small quantities in life makes your heart healthier. Oxygen is both good and bad. The structure does not give the property.
to most electronegative are H ≅C < N < O and that molecules with highly electronegative elements (Nitrogen and Oxygen) are polar, hydrophilic, and most likely to form hydrogen bonds. For example molecules with polar-covalent bonds (weak electrical charge) may form hydrogen bonds with other polar molecules.

a hydrogen atom, with one electron in its outer shell, forms only one bond, such that its outermost orbital becomes filled with two electrons. A carbon atom has four electrons in its outermost orbitals; it usually forms four bonds, as in methane (CH₄), in order to fill its outermost orbital with eight electrons. The single bonds in methane that connect the carbon atom with each hydrogen atom contain two shared electrons, one donated from the C and the other from the H, and the outer (s) orbital of each H atom is filled by the two shared electrons:

Nitrogen and phosphorus each have five electrons in their outer shells, which can hold up to eight electrons. Nitrogen atoms can form up to four covalent bonds. In ammonia (NH₃), the nitrogen atom forms three covalent bonds; one pair of electrons around the atom (the two dots on the right) are in an orbital not involved in a covalent bond.

d.Every chemical reaction involves a change in free energy, called delta G (∆G). To calculate ∆G, subtract the amount of energy lost to entropy (∆S) from the total energy change of the system; this total energy change in the system is called enthalpy (∆H ): ΔG=ΔH−TΔS

If the free energy of A is greater than the free energy of B then the reaction A to B will be spontaneous, or in thermodynamic terms, energetically favorable.Thus we determine the chemical reaction is favorable.