* Athens' ATG edges up but remains close to 3-year lows
* Copenhagen stocks rise after Denmark election result
* Europe bourses in 2015: link.reuters.com/pap87v
* Asset performance in 2015: link.reuters.com/gap87v
By Sudip Kar-Gupta
LONDON, June 19 (Reuters) - European shares gained ground on Friday, boosted by a rise in French telecom stocks and at steelmaker Thyssenkrupp, although persistent concerns over Greece kept a lid on the overall progress.
The pan-European FTSEurofirst 300 index rose 0.8 percent, as did the euro zone's blue-chip Euro STOXX 50 index . Germany's DAX advanced 0.7 percent while France's CAC climbed 0.8 percent.
French telecoms group Numericable rose 2.9 percent while Orange progressed 1 percent after France announced a mobile spectrum sale.
Thyssenkrupp also advanced 2.7 percent after Citigroup upgraded its rating on the stock to "buy" from "neutral".
European indexes also rode on the coattails of a strong performance on Wall Street on Thursday, where the Nasdaq Composite erased its last standing milestone from the dot-com era when it set a record intraday high.
Nevertheless, some traders remained cautious given the deadlock between Greece and its creditors.
Euro zone leaders will hold an emergency summit on Monday to try to avert a Greek default after bank withdrawals accelerated and government revenue slumped as the Greek debt talks drag on.
Athens' benchmark ATG index edged up by 0.5 percent but remained close to three-year lows reached earlier in the week, with the ATG down 17 percent so far in 2015, underperforming a 12 percent rise on the FTSEurofirst.
Richard Griffiths, associate director at Berkeley Futures, said the uncertainty over Greece meant he would avoid holding "long" positions -- namely those betting on future gains -- on the stock market going into the weekend.
"We're really only up on the back of the strength in the U.S., but I'd still be inclined to sell the rallies because of the Greek situation. It would be a brave man who goes in 'long' into the weekend," said Griffiths.
Denmark's benchmark equity index rose 1.2 percent after Danish voters ousted Prime Minister Helle Thorning-Schmidt in an election on Thursday and handed power to an opposition centre-right alliance including huge gains for a eurosceptic, anti-immigrant party.
Denmark, along with many other countries, has launched economic stimulus measures such as interest rate cuts in order to boost trade and business.
Similar measures from the European Central Bank (ECB) have also cushioned the blows to European financial markets from the problems with Greece, enabling some investors to maintain a positive attitude in spite of the worries over Athens.
"There is always opportunity in crisis. You may have to weather a little short-term pain should the worst case ensue, but ultimately you will be rewarded," said Gary Paulin, co-founder of brokerage Aviate Global.
Today's European research round-up