Breast cancer is the most common type of cancer in women worldwide and divided into two sub-groups: invasive lobular and invasive ductal carcinoma. Invasive ductal carcinoma accounts for 80% of breast cancers. Triple negative breast cancer (TNBC) is also an aggressive type of breast cancer that fail to amplify estrogen receptor, progesterone receptor and human epidermal growth factor receptor 2. Intercalarily, RNA methylations have proven their effects on cell fate, especially in cancer studies. m6A and m1A have dynamic regulation mechanisms catalyzed by writer, reader and eraser proteins. These proteins have different expression levels based on cancer types and intended to be used for therapeutic/diagnostic approaches. In the current thesis study, it was aimed to examine the effects and comparison of m6A and m1A methylations in TNBC cell line, HCC1143, after METTL3 or TRMT61A silencing. Firstly, the maximum level of reduction in methylation amounts was attained at 72-hour as 41.2% decrease in m6A amount. To examine the phenotypic effects of silencing, we performed viability experiments and observed 40.1% and 27.4% decrease by METTL3 and TRMT61A knock-down, respectively. Additionally, G2/M phase arrest was observed upon METTL3 silencing. RNA sequencing experiments were conducted to evaluate the effects of knockdown at the molecular level. 585 differentially expressed genes (DEGs) were detected after reduction in m6A and 687 DEGs after TRMT61A silencing. 151 DEGs were common. Based on GO analyses, cell migration pathways were intensely observed in METTL3 while variability was observed in the immune-related and negative regulation of proliferation pathways after TRMT61A knock-down.