Drugs for Cancer Therapy

Over 300 disorders

oncology incldes how many disorders?

They lack contact inhibition and adhesion. They dont stick like normal cells most

why are cancer cells more invasive and easily spread?

TMN:

Tumour: characteristics, depth of invasion

Node involvement

metastasis to other organs

most commonly used cancer staging system:

1. surgery

2. radiation therapy

3. interventional radiology

4. chemotherapy

Common cancer treatments [4]

chemotherapy

The use of medications in the treatment of cancer

Cyber knife

The use of radiation to cut tumours out:

1. cure: eliminate cancer

2. control: when disease is not curative

3. palliation: relieve symptoms when they arise

goals of chemotherapy [3]

Neoadjuvant chemo

Chemo to shrink tumours so they are more easiy resected surgically

Adjuvant chemotherapy

Chemo used in conjection with another treatment modality. For localized diease.

intermittent chemotherapy

Allowing time intercals between chemotherapy treatments

Combination therapy

Administration of two or more chemo agents to treat cancer

Cell kill hypothesis

a certain chemotherapy dosage will kill a constant percentage a cells, rather than a constant number.

Tissues that are continuing to divide

Chemotherapy is more toxic to which kinds of tissues?

chemotherapy. Dosed in milligrams/metre squared

body surface area is used to calculate which drugs?

Based on bbody surface area, height and weight. Could lose weight (N+V) or gain weight (steroids)c

why do chemotherapy drug dosings need to be reevaluated each cycle?

1. antineoplastic or cytotoxic

2. targeted therapy

3. immuno-oncology agents

4. hormones

classifications of chemotherapy agents: [4]

Antineoplastics/cytotoxicsf

these agents are sub-classified by chemical structure, cell cycle activity, and primary mode of action wihtin the cell

1. alkylating agents

2. antimetabolites

3. anti-tumour antibiotics

4. vinca (plant) alkaloids

four sub-classifications of antineoplastics/cytotoxics

Alkylating agents

antineoplastic/cytotoxic that does not target a specific place in the cell cycle

“aklyl” group causes breaks in DNA strands, preventing DNA replication and transcription of RNA

Alkylating Agent MOA

Drug resistance is common

Alkylating agents are commonly used in combination chemotherapy regimens. Why?

Cisplatinum

carboplatinum

oxiplatin

“platinum” based alkylating agent therapies [3]

Cyclophosphomide

Nitrogen mustard alkylating agent therapy

Temozolamide

Nitrosoureas alkylating agent therapy that crosses the blood brain barrier (good for brain cancer)

S phase

Antimetabolites target what pase of the cell cycle?

Acts as false metabolites which are incorporated into the DNA strand and prevent DNA and RNA synthesis

Antimetabolite MOA:

•5- Flurouracil (5-Fu) [breast]

•Pemetrexed (Alimta) [lung]

•Methotrexate (MTX) [can be used for autoimmune disorders, anti-rejection]

•Gemcitabine (Gemzar)

•Capecitabine (Xeloda)

Common forms of antimetabolites [5]

Antitumour antibiotics

Natural compounds found in various strainsof streptomyces, a soil fungal organism. Is cell cycle non-specific.

1. breaks DNA strands

2. inhibits DNA and RNA synthesis

3. alters cell membrane

Antitumour antibiotic MOA: there are a variety [3]

►Doxorubincin / Adriamycin

►Epirubicin [bladder cancer]

►Bleomycin

►Mitomycin

Common forms of antitumour antibiotics [4]

Vinca Alkaloids

Plant alkaloid produced from periwinkle plant

Halt cell cycle in M phase by crystallizing microtubules of mitotic spindles, thus inhibiting mitosis

Vinca ALkaloid MOA:

Prevents cells from entering M phase, inhibiting mitosis

Epipodophyllotixin MOA

►Vincristine

►Vinorelbine

Vina alkaloid prototypes: [2]

Etoposide

epipodophyllotixin prototype

1. vinca alkaloids

2. epipodophyllotoxins

3. taxanes

4. topoisomerase inhibitors

Plant alkaloids: [4]

taxotere.docetaxol

Taxane that is used as a third line treatment, like a last-ditch effort

Taxanes

PLant alkaloid where cells are prematurely thrown into cell division or cell divisiion arrested

Topoisomerase inhibitors

Semi-synthetic extract from the plant Camptotheca Acuminata from asia

Act in S phase to inhibit topoisomerase and cause cell death

Topoisomerase inhibitor MOA:

Camptosar/Irinotecan

Topoisomerase inhibitor prototype

targets specific molecules that cancel cells possess (genes,proteins, antigens.) to halt or interfere with their tumour promoting activity

target therapies MOA

Monoclonal antibodies

Targets one cancer cell antigen on te cancer cell surface

Inhibitors of Her 2 and Her 3 proteins which are over expressed on breast cancer cells.

1. ▪Trastuzumab/Herceptin (IV therapy)

   ▪Trastuzumab Emtansine/Kadcyla

   ▪Pertuzumab/Perjeta

Monoclonal antiodies for breast cancer treatment: [3]

Targets the KRAS oncogene

▪ Panitibumab (Vectibix) – Colorectal Cancer

▪Cetuximab (Erbitux) – Colorectal Cancer

Gene targeted in Colorectal cancer (two targeted therapies)

Immuno-oncology agents

Modifies the host immune system to respnd to cancer. “takes the breaks” off the immune system

1. stimulates T-cells to target cancer cells and stop proliferation

2. creates memory cells in immune system that continue to act against cancer after treatment period

3. stimulates natural killer in immune system

Immuno-oncology agent MOA [3]

Nivolumab (Opdivo ®)

immuno-oncology agent that acts on lung and renal cell

Pembrolizumab (Keytruda®)How

immuno-oncology agent that acts on lung and melanoma:

Used in management of hormone sensitive cancers such as breast and prostate. Changes the hormonal environment of cancer cells by suppressing or eliminating hormonal growth factors

How are hormones used in cancer treatment:

•Tamoxifen, Arimidex, Femara

•Casodex, Eligard, Lupron

•Abiaterone, Xtandi

Common forms of hormones used in cancer treatment [3]

1. bone marrow

2. GI tract

3. hair follicles

Rapily dividing cells are found in: [3]

rapidl dividing cells

1. healthy and

2. cancer

Cancer is toxic to:

myelosuppression

Bone marrow suppressoin. Monitored by WBC and differential

leukopenia/neutropenia

decreased white blood cell and neutrophil couunt

Nadir period

Usually the middle of the chemo cycle. All blood values will be the lowest.

An oncolic emergency. Body cannot fight infection, can be fatal.

Fever as cancer side effect is what?

Anemia

decreased hemoglobin

Thrombocytopenia

Decreased platelet count

1. antibiotics

2. antigunals

3. antivirals

medications given for neutropenia [3]

Granulocyte stimulating factors

helps to build WBCs. If they fall below 1.9, have to delay chemo

blood transfusion

Nursing management for severe anemia:

high iron, folate, and B12 diet

Anemia diet

injury and bleeding prevention: avoid activities that can cause cuts or bruises, avoid activities with risk of physical injury

Patient education for thrombodytopenia

Alopecia

Cmplete hair loss or thinning of hair related to the use of specific drugs

Hand foot syndrome (plantar-almar erythrodysthesia)

Skin reaction to palms and soles. Tingling, redness, numbess, swelling, pain, dry, itching, peeling. onset 5-6 weeks after treatment starts

decrease the dose, decrease side effects. But need to give appropriate dose to treat the cancer

treatment for hand foot syndrome

Capectitabine (Xeloda)

may also be seen with high dose 5- Flouracil and many new targeted agents

hand foot syndrome is common with what drug?

Vitamin B6

What may be rpescribed for hand-foot syndrome?

Stomatitis

Inflammation/infection of oral mucous membranes

avoid mouthwashes and specialty toothpaste. Use soft tooth brushbrush, popsicles, ice chips, salt water rinse

Stomatitis prevention:

“magic mouthwash” and prescription preparations (antiseptic)

Treatment for stomatitis:

1. acute (first 24 hours

2. delayed

3. anticipatory (pior to treatment)

Three types of snausea and vomiting

cater to preferences, small frequent meals throughout day, avoid odors with foods & cooking

nutrition for N+V

Neurokinin 1(NK₁) Receptor antagonist

anti-emetic that decreases NT involved in emetic response. Normally given for cancer tx

•Fosaprepitant (Emend®)

Neurokinin 1(NK₁) Receptor antagonist protoype:

bowel obstruction. Stimulates GI motility

Dopamine antagonists (maxeran) should not be given when?

Phenothiazine derivatives:

Antipsychotic that is also goo at treating cancer N+V

Prochlorperazine (Stemetil®)

Phenothiazine derivative prototype

bananas

rice

applesauce

Tea

BRAT diet for N+V

combined radiation

chemotherapyre

Diarrhea is worsened with…

fluid/ electrolyte imbalance

renal toxicity commonly manifests as

hematuria

bladder toxicity normally manifests as

Mesna

renal protective agent

1. diuretics

2. renal protective agents

meds for renal/bladder toxicites [2]