## 1 Introduction  
Colorectal cancer (CRC) is a disease that accounts for 10% of diagnosed (1.9 million) tumors and cancer-related deaths (935,000) worldwide [1]. Its incidence is lower in women (32 out of every 100,000) compared to men (42 per 100,000), being mainly diagnosed in developed regions such as Europe, Australia, and North America, and with Hungary and Norway being the two countries with the highest incidence [1]. In a gradual process, it is estimated that the incidence of this type of cancer will increase over the next few years, reaching a diagnosis of 2.5 million new cases in the year 2035 (600,000 more than currently) [2]. Family history of cancer is linked to 10-20% of diagnosed patients, with 5-7% of all patients being correctly defined as having a hereditary syndrome. In addition, there are risk factors that predispose to this disease, such as smoking, alcohol consumption, overweight and intake of red meat and processed food [3]. This disease initially presents as a malignant polyp that will progressively evolve into cancer within 10-15 years through a chromosomal instability resulting from a mutation in the APC gene, an activation of the RAS proto-oncogene and a loss of function of the TP53 tumor suppressor [4]. It is due to this progressive process that the risk of incidence of this disease is linked to age, increasing from 2.1 cases/100,000 inhabitants in the 25-29-year age group to 234.7 cases in the over 85-year age group in the United States [5]. Due to the screening programs of international health systems, the incidence of this type of tumor has increased, as well as its early diagnosis. Thus, most European countries have a nationally organized screening system since 2003, as do North America and Eastern countries such as Japan, South Korea, Taiwan, Thailand, and Australia. Meanwhile, many countries in Central and South America do not have organized programs due to the limited resources available to them [6]. In early-stage localized tumors or large polyps, endoscopic resection may be the correct therapy for patients [7]. Surgery is also a curative therapy in colon cancer, with laparoscopy being the standard technique in several countries worldwide [8]. Meanwhile, the treatment of rectal cancer is more complicated, with mesorectal excision being the gold standard of treatment [9]. Meanwhile, in metastatic patients, the long-term curative options are based on the total elimination of metastatic nodes by surgery. Thus, resection of these secondary tumors allows the cure of 20% of patients, although it remains incurable for the vast majority. Current treatment is based on the use of pyrimidine analogues (5-fluorouracil, known as 5-FU, and capceitabine), alkylating agents (oxailplatin) and topoisomerase I inhibitors (irinotecan), alone or in combination with others in regimens such as FOLFOX (folinic acid, 5-FU and oxaliplatin), FOLFIRI (folinic acid, 5-FU and irinotecan) or FOLFOXIRI (folinic acid, 5-FU, oxaliplatin and irinotecan) [10; 11]. Additionally, there are new treatments based on monoclonal antibodies or immunotherapy that could be useful [12]. One of the greatest anticancer drugs at present are PD-1 inhibitors such as pembrolizumab, which is approved by the European Medicines Agency (EMA) for use in microsatellite instability in colorectal cancer (MSI-H/dMMR) resistant to standard chemotherapy. An increase in disease progression-free survival during the duration of response of 24 months versus chemotherapy has been demonstrated, in addition to a better safety profile [13]. Despite the latest advances in treatments applied in clinics, the results when the disease is advanced are still limited, and the search for new, more selective, and more effective antitumor agents are necessary. In recent years, the use of natural products as a possible antitumor treatment has been proposed as a possible tool.