ROLE OF ANTI-HISTAMINE IN BREAST CANCER
Breast cancer occurs when a healthy cell grows out of control and forms a tumor and it can spread to other parts of the body. About 1 in 8 women are diagnosed with cancer in their lifetime. Breast cancer develops inside the milk ducts which is called Ductal Carcinoma (DCIS). When abnormal DCIS cells spread to surrounding tissue is known as Invasive Ductal Carcinoma (IDC). An abnormal cell may also develop into lobules called Lobular Carcinoma in Situ (LCIS) and are not cancer, when it spreads to the surrounding tissue then it becomes cancer called Invasive Lobular carcinoma. As an inflammatory environment maintained in tumours, an anti-inflammatory medication may be useful in Cancer treatment . H2- anti-histamine has shown promising results in cancer treatment. Investigators showed a link with improved survival in melanoma by using H1- antihistamine. Six antihistamines namely, cetirizine, desloratadine, ebastine, fexofenadine, clemastine and loratadine were investigated by researchers in a nation-based study of all 61,627 Swedish women identified with breast cancer from 2006-2013. By using Cox regression models both pre- and post-diagnostic antihistamine use was analysed. Based on subgroup and age oestrogen receptor status and menopausal status were executed. Within the patient population based on safety and current use scientists found that desloratadine users had improved survival rates including loratadine users compared to non-users, irrespective of menopause status, oestrogen receptor status and patient age. Other antihistamines which were consumed by survival users experienced change compared to non-users . The TMC engage in a huge role in the progression of cancer. Throughout the metastatic period, the malignant cells familiarize themselves with the TMC and activate pathways to promote tumor growth by using local signals. In the breast cancer progression, TAK-1 activating cytokines are present in TMC, higher level of interleukin-1 has been linked with the aggressive proliferation of breast cancer . The latest verdict has shown that the anti-histamine drug Loratadine can also have anti-inflammatory properties even though the exact mechanism is still unknown. In this researchers investigated if loratadine can be used as an anti-inflammatory drug through in-vitro and in-vivo experiments using macrophage cell lines. Later it was concluded that loratadine exhibits anti-inflammatory action in macrophage cell lines, specifically inhibiting the AP-1 signaling pathway and targeting TAK-1(Figure 7), and suppressing AP-1 transactional activity. In this manner, it reduces the pro-inflammatory mediator’s expression together with MMP3, MMP1, and MMP9 . The researchers believe further studies of H1-antihistamine use needs to be conducted for survival in breast cancer .