ABSTRACT
Plectranthus excisus is widely distributed throughout northeast China. Its active ingredient, diterpenoids, exhibits significant antitumor effects. The present study examined the antitumor effects of diterpenoid B (DB), derived from Plectranthus excisus, and demonstrated that DB inhibited the proliferation of tumor cells by inhibiting the cell cycle. Reverse transcriptionquantitative polymerase chain reaction and western blot analysis were used to determine mRNA and protein expression levels, respectively. The results revealed that exposure to DB increased the expression levels of the transformation associated, protein 53, and cyclindependent kinase inhibitor 1A, and decreased the expression of cyclindependent kinase 2. The results of the present study demonstrated that DB can inhibit cell cycle progression and, therefore, offers potential as a beneficial antitumor drug.
