By Devik Jain and Amruta Khandekar (Reuters) -European shares edged lower on Monday as investors stayed cautious ahead of major corporate earnings this week, with nerves around rising interest rates and escalating geopolitical tensions also weighing on sentiment. The region-wide STOXX 600 index was briefly in positive territory before closing down 0.4% and extending losses to a fourth straight session. Geopolitical concerns festered on Monday after Russia launched its most widespread air strikes since the start of the Ukraine war, in what President Vladimir Putin called revenge for the explosi…