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We study the nonlinear evolution of optical vortices in light-induced photonic lattices under nonconventional bias conditions based on an anisotropic model.It is revealed that, in the presence of anisotropy, the vortex beams can evolve into asymmetric discrete vortex soliton states with four-lobe structures.Generally,the intensities of different lobes become nonuniform, but the diagonal two lobes possess an identical intensity.By tuning the lattice beam intensity and the external bias field, the vortex beam could evolve into a stationary dipole structure.Remarkably, the asymmetric soliton states with four lobes forming rhomboid configurations are observed under nonconventional bias cases.It is surprising that the topological sign of the input vortices plays a nontrivial role in the evolution dynamics of the vortex beams.In addition, the topological transformations including the charge flipping and orbit angular momentum inversion can also be observed in the nonconventionally biased cónditions.All the above phenomena can be interpreted by the interplay among the vortex orbit angular momentum, the lattice periodicity and the anisotropic nonlinearity.