Abstract
Globally, the prevalence of cancer has escalated at an alarming rate, and it
has become a major health problem. The World Health Organization reported that one
in six deaths is due to cancer. Despite the advantages of current chemotherapy
available for cancer treatment, the development of resistance and severe side effects
continuously insist cancer research focus on the discovery of new entities, especially
from natural sources. In the last few decades, varieties of dietary herbs have been
explored for their cytotoxic potential. Rosmarinus officinalis, a well-known culinary
herb commonly known as rosemary, is not only used to enhance the flavour but also
possesses medicinal values. The Rosmarinus officinalis plant extract and its essential
oil are packed with different phenolic acids and terpenoids. Rosmarinus officinalis has
anti-cancer, anti-proliferative, protective, anti-inflammatory, and anti-oxidant
properties, according to several in vitro and in vivo studies. The antitumor activity of
Rosmarinus officinalis is correlated with different molecular mechanisms such as
reactive oxygen species scavenging, the on-co-suppressor gene expression, apoptosis,
and immunomodulatory response regulation. So this chapter mainly focuses on the
cytotoxic activities of Rosmarinus officinalis and the molecular mechanisms
responsible for their anticancer activities. Also, possibilities of utilising the extracts,
essential oils, and phytochemicals of Rosmarinus officinalis as potential therapeutic
agents or complementary therapies with chemotherapeutic agents for cancer treatment
have been discussed.