を中心に|をちゅうしんに

1. 1With a place as the center or main area where something takes place (mainly in, centered on).Ex. 1
2. 2With a group or thing as the core or main part of a trend or activity (mainly among, especially).Ex. 2

Common in news, reports, and explanations that describe where an activity is concentrated or who is chiefly involved. を中心として is slightly more formal. Unlike topic markers such as について and に関して, を中心に names the center or main weight of an activity, not the subject being discussed.

• 1.
  をめぐってN2「をめぐって」indicates that an issue becomes the focus of debate or negotiation among multiple parties; the following clause usually describes actions involving many people, and it is rather formal. 「を中心に」emphasizes where the center of gravity lies and how it extends to other things, and can also refer to a physical location, so the two are generally not interchangeable.
• 2.
  をはじめ / をはじめとするN3「をはじめ」picks out the most prominent or representative item and then brings in other items of the same kind or the whole; it does not express a center of focus or outward expansion. It is mostly used in formal contexts such as speeches and news, and swapping it with 「を中心に」changes the meaning.
• 3.
  に関する / に関してN3「に関して／に関する」only marks the topic, meaning 'regarding ~', with no sense of 'taking this as the focus while also covering other things', and it cannot express being centered on a location; it is somewhat formal. When discussing an issue it can be substituted, but the meaning becomes a simple statement of the topic.
• 4.
  をもとにN2「をもとに」means using the preceding item as material or a basis to produce something through creation, processing, or judgment; 「を中心に」means taking the preceding item as the focal point, with the scope extending to surrounding or other objects. The meanings differ, so they are generally not interchangeable.
• 5.
  についてN3「について」only introduces the topic of speaking, thinking, investigating, and so on; it carries no sense of 'taking this as the focus while also covering other things', nor does it express expansion from a central location. To modify a noun, use 「についての」, not 「を中心とした」.

を中心に marks the center or main focus of an activity, whereas について / に関する mark the topic being discussed, をめぐって marks an issue surrounded by debate or conflict, and をもとに marks the material or basis something is made from. をはじめ names one representative item first and then points to others, while を中心に stresses where the main weight lies.