MassMutual Financial Group laid off 150 employees Tuesday as a result of its $165 million takeover earlier this year of MetLife's life insurance sales operation. The layoffs were spread out over 10 offices, including the insurance giant's headquarters on State Street in Springfield. "We have been working to integrate the organizations," said MassMutual spokesman James Lacey. "When you do so, you have overlaps and redundancies. These were difficult decisions that were not made lightly and we are committed to providing support and respecting the privacy of those affected by the decisions."