Abstract
Breast cancer is the most common cancer among women in terms of prevalence and mortality, and chemotherapy is one of the most effective treatments at higher stages. However, resistance to chemotherapy is the main obstacle in the treatment of this cancer. Accumulated evidence identified the PD-L1 protein as an essential protein in the development of different cancers. Abnormal expression of this protein in various tumor cells is linked to cancer development and inhibiting the function of immune cells, which correlated with reduced beneficial effects of chemotherapy drugs. In the present study, the effects of common chemotherapy drugs including doxorubicin, paclitaxel, and docetaxel on the expression of the PD-L1 gene were investigated by qRT-PCR before and after the treatment with these drugs in MD231, MD468, SKBR3 breast cancer cell lines. Also, the MTT test was applied to examine the effects of drugs on the growth and proliferation of cancer cells considering PD-L1 expression. The expression of the PD-L1 gene increased after 24 and 48h of treatment with chemotherapy drugs. The obtained results indicate the enhancing effects of chemotherapy drugs on PD-L1 gene expression, which have a suppressive effect on the immune system against breast cancer. The use of these drugs as the first line of chemotherapy in triple-negative breast cancer is not recommended. However, there is still a need for further experimental and clinical research on the exact effects of these drugs on undesired immune cells exhaustion in breast cancer therapy.
Highlights
Breast cancer is the most common cancer in women worldwide with two million new cases and with a mortality rate of 600,000 deaths in 2018 [1]
We examined the potential effects of common regimens applied in breast cancer therapy, including doxorubicin and taxanes on PD-L1 expression in breast cancer cell lines
To determine the effective dose (IC50) of the drugs, including Doxorubicin, Paclitaxel, and Docetaxel in the MDA-231 (Fig. 1), MDA-468 (Fig. 2), SKBR3 cell lines (Fig. 3), the values of which were interpreted according to Table 2
Summary
Breast cancer is the most common cancer in women worldwide with two million new cases and with a mortality rate of 600,000 deaths in 2018 [1]. This condition of the disease needs special attention in terms of prevention and treatment. Basal-like and TNBC subsets account for about 15% of invasive breast cancers. The 1-year and 3-year survival rates of patients with TNBC are slightly lower than other cases of breast cancer. While 5-year and 10-year survival rates, without association with other diseases, are very low in these patients [8, 9]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
