Hormone Receptor-Positive (Hr+) Breast Cancer

Hormone Receptor 

Hormones are chemical signals that circulate in the blood. Hormone receptors are proteins that are located in and around the breast cells. The cells grow and divide when the corresponding hormone binds to a receptor. In the case of breast cancer, the receptors allow abnormal cells to grow and multiply out of control, which results in a tumor.

Hormone Receptor-Positive Breast Cancer 

The two types of breast cancers are estrogen and progesterone receptors. Estrogen and progesterone are hormones that promote the growth of breast cancer cells. These hormones bind to the estrogen and progesterone receptors. Hormone receptor-positive breast cancers may be positive for estrogen receptors (ER+), progesterone receptors (PR+), or it can be both (ER+/PR+). About 80% of all hormone receptor-positive breast cancers are estrogen receptor-positive (ER+) or both (ER+/PR+). 

Treatment Options For Hormone Receptor-Positive Breast Cancer 

1. Hormonal Therapy 

Hormonal therapy, also called anti-estrogen therapy or endocrine therapy, is used to treat all stages of hormone receptor-positive breast cancer. Hormonal therapy works in two ways by blocking estrogen production in the body or by blocking the effects of estrogen on breast cancer cells. Three major types of hormonal therapy medicines are used to treat breast cancer. They are,

• Aromatase inhibitors

• Selective estrogen receptor modulators (SERMs)

• Estrogen receptor down regulators (ERDs)

1.1 Aromatase Inhibitors

Aromatase inhibitors function by inhibiting the enzyme aromatase, which converts the hormone androgen into small amounts of estrogen in the body. Because aromatase inhibitors cannot prevent the ovaries from producing estrogen, they are mostly used to treat post-menopausal women whose ovaries are no longer functioning.

1.2 Selective Estrogen Receptor Modulators (SERMs)

By binding to estrogen receptors, selective estrogen receptor modulators (SERMs) inhibit the effects of estrogen on breast cancer cells. If a SERM is present in the estrogen receptor, then the hormone estrogen cannot attach to the cancer cell, and the cell does not receive signals to grow and multiply. This can be used to treat both pre and post-menopausal women and men. 

1.3 Estrogen Receptor Down Regulators (ERDs)

Estrogen receptor down regulators (ERDs), like SERMs, bind to estrogen receptors and prevent estrogen's actions on breast cancer cells. ERDs also reduce the number of estrogen receptors in the breast cell and alter the structure of estrogen receptors, making them less effective.

2. Cyclin-Dependent Kinase Inhibitors (CDK 4/6 Inhibitors)

CDK4/6 inhibitors are a targeted therapy used to treat certain hormone receptor-positive, HER2-negative breast cancer types.

Targeted therapies are medications that target specific characteristics of cancer cells, such as a protein that allows cancer cells to proliferate abnormally or rapidly. Targeted medicines are less likely to kill normal, healthy cells than chemotherapy. Some targeted therapies are antibodies that function similarly to antibodies produced naturally by our immune systems. Targeted therapies are sometimes called immune-targeted therapies. CDK4/6 inhibitors disrupt the division and multiplication of breast cancer cells. To do this, they target specific proteins known as cyclin-dependent kinases 4 and 6. 

Cydekin 75mg Capsule is a targeted therapy containing the active constituent palbociclib. It belongs to the group of anticancer medications known as cyclin-dependent kinase inhibitors.  It is used to treat advanced or metastatic (has spread to other parts of the body) hormone receptor-positive, human epidermal growth factor 2 negative breast cancer. Cancer is a disease in which cells proliferate uncontrollably and abnormally. It is administered in addition with other anticancer drugs. Cydekin 75mg Capsule works by inhibiting the protein cyclin-dependent kinases 4 and 6, which are required for cell division and proliferation. This medicine reduces the growth of cancer cells and prevents them from spreading by blocking these proteins.