Biclustering plays a crucial role in many real world applications. Related to clustering, which groups similar rows in a matrix (data table), biclustering aims at simultaneously grouping similar rows and columns, i.e. to find submatrices which exhibit a correlation among their respective cells. There are many types of biclustering based on a similarity criterion. In this paper we are interested in constant- column (CC) biclustering, where the objective is to discover submatrices whose columns have a constant value across all the rows. Then, we study an extension of CC biclustering to the so-called coherent-sign- changes (CSC) biclustering.