The most recent classes of dendrimers have also been developed to carry a therapeutic medication, a diagnostic agent, and an active targeting molecule all in one dendrimer therapy. They are characterized by their inner core and tree-like branches that offer enormous amounts of surface area for drug attachment [37, 38]. In order to achieve targeted drug administration, it is clear that nanotechnology, which involves the generation of numerous nanoparticles with different shapes and behaviors, can open up a vast range of options. Numerous techniques have been used to demonstrate how nanotechnology can be used to cure cancer. They include, but are not limited to: photothermal cancer cell elimination, gene therapy, and intracellular drug delivery for therapeutic purposes [39, 40]. Angiogenesis is used in the delivery of intracellular chemotherapy. Angiogenesis, the formation of new blood vessels used by tumor cells to expand by taking nutrients and oxygen from surrounding cells, is one of the traits of cancer. Angiogenesis blood vessels form unevenly and are more leaky than typical healthy vasculature as a result of their fast, uncontrolled growth [41]. These vessels have pores that are between a few hundred nanometers to several microns in size, as opposed to ordinary vessels, which only have pores that are 2–6 nm in size. Nanoparticles’ diameter, which ranges from 10 to 300 nm, makes them the ideal size for entering tumor cells’ blood arteries without significantly damaging healthy tissues [41]. This Trojan horse approach offers an attractive way to reduce harm to neighboring cells. Another approach is photo­thermal ablation makes use of the difference between the average apoptotic temperature of cancer cells, which occurs at about 42 °C, and normal cells, which occur at about 46 °C. Gold nanoparticles that are made to only excite at particular light frequencies have been used in multiple studies to target and kill specific tumor cells while sparing the surrounding healthy cells [42]. Nanotechnology has the ability to overcome the shortcomings of current methods, such as reducing the health risks associated with treatments depending on viruses. Researchers successfully developed nanoparticles using a synthetic delivery method and small interfering ribonucleic acid (siRNA) to reduce the expression of RRM2, a known anticancer target [43].

Additionally, doxorubicin (DOX) and irinotecan both have single-agent activity and have been widely used in clinical practice. In slightly acidic conditions, gastric cancer cells demonstrated higher absorption and greater toxicity to nanoparticles than single components of an irinotecan hydrochloride curcumin nano system [75]. For chemo-photothermal synergistic therapy, Zhou and his team encapsulated DOX in a pH-sensitive, long-circulation nanoparticle [76]. Yang and his associates showed how to treat gastric tumors that overexpress Her2 and CD44 using dual­targeting hybrid nanoparticles [77]. Delivering the nanoparticle to stomach cancer cells preferentially is made possible by the anti-Her2 peptide and hyaluronic acid on the surface of NPs that carry the SN38 agent. Treatment for stomach cancer is still hampered by the persistence of chemotherapy resistance, which results in tumor recurrence and chemotherapy failure [78].