Abstract: The present invention is inserted in the fields of nanotechnology, pharmacy and genetics and refers to specific sequences of interference RNA (siRNA), capable of silencing the gene responsible for the expression of an adhesion protein, which produces overexpressed extracellular adenosine in tumors, the enzyme ecto-5?-nucleotidase/CD73 (CD73). The specific siRNA sequences for CD73 are proposed in a nanometer scale composition in the form of liposomes or nanoemulsions in order to promote a site-directed release complex capable of being incorporated into several types of formulation, such as intratumor, intravenous injection or administration nasal. The siRNA sequences to silence CD73 can also be applied in the manufacture of kits and/or in silencing tests of CD73 for scientific research using liposomes, nanoemulsions or other transfection reagents.