TOKYO, July 4 (Reuters) - Japan's Nikkei share average edged up in early trade on Wednesday, supported by keen interest in domestically driven stocks and improved sentiment amid expectations central banks will act to support flagging global growth. The Nikkei rose 0.5 percent to 9,113.09, helped by gains for cyclical stocks such as industrial machinery and mining companies, while safer bets such as pharmaceuticals underperformed.