Tron surged 10% after founder Justin Sun announced plans to integrate TRX into the Solana ecosystem.US spot Bitcoin ETFs showed encouraging signs with US$274.6 million in net inflows on Monday.NASDAQ filed a 19b-4 for a 21Shares Polkadot ETF, adding to the growing list of altcoin ETF applications.Litecoin and Dogecoin are the most likely candidates for ETF approval according to Bloomberg ETF analyst James Seyffart.