Can a commercial lease be terminated before expiration date?

Typically no, because the Landlord has committed their property to the Tenant for that specific period of time with the expectation they are going to fulfill the financial obligations. This is especially true if the Landlord spent additional capital performing tenant improvements. In addition, many time financing is based upon the successful completion of the lease.  A Tenant does have the ability to sublease their space by locating a qualified replacement tenant to take over the remainder of the term. However, it should be pointed out that a sublease does not relieve the original Tenant of their lease obligations in the event the Sublessee defaults and the Sublessor remains on the hook.