Hello navid007.
WinCC can be an OPC client.
So all you need is an appropriate OPC Server for the hardware that you intend to use with the Toshiba PLC.
As I do not know the Toshiba PLC, I cannot say if you can connect it with a Master-to-master profibus connection. This would be quite easy if it is possible.
If not, there is the possibility to let either WinCC or the Toshiba PLC be Profibus slaves.
If you can consider other networking standards besides PRofibus, then you shall just have to find one that provides an OPC Server for which WinCC can connect to as OPC Client.