Identification of actin-depolymerizing factor homology (ADF-H) domains in the structures of several related proteins led first to the formation of the ADF/cofilin family, which then expanded to the ADF/cofilin superfamily. This superfamily includes the well-studied cofilin-1 (Cfl-1) and about a dozen different human proteins that interact directly or indirectly with the actin cytoskeleton, provide its remodeling, and alter cell motility. According to some data, Cfl-1 is contained in various human malignant cells (HMCs) and is involved in the formation of malignant properties, including invasiveness, metastatic potential, and resistance to chemotherapeutic drugs. The presence of other ADF/cofilin superfamily proteins in HMCs and their involvement in the regulation of cell motility were discovered with the use of various OMICS technologies. In our review, we discuss the results of the study of Cfl-1 and other ADF/cofilin superfamily proteins, which may be of interest for solving different problems of molecular oncology, as well as for the prospects of further investigations of these proteins in HMCs.

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This review considers the major features of human proteins AGR2 and ERp57/GRP58 and of other members of the protein disulfide isomerase (PDI) family. The ability of both AGR2 and ERp57/GRP58 to catalyze the formation of disulfide bonds in proteins is the parameter most important for assigning them to a PDI family. Moreover, these proteins and also other members of the PDI family have specific structural features (thioredoxin-like domains, special C-terminal motifs characteristic for proteins localized in the endoplasmic reticulum, etc.) that are necessary for their assignment to a PDI family. Data demonstrating the role of these two proteins in carcinogenesis are analyzed. Special attention is given to data indicating the presence of biomarker features in AGR2 and ERp57/GRP58. It is now thought that there is sufficient reason for studies of AGR2 and ERp57/GRP58 for possible use of these proteins in diagnosis of tumors. There are also prospects for studies on AGR2 and ERp57/GRP58 leading to developments in chemotherapy. Thus, we suppose that further studies on different members of the PDI family using modern postgenomic technologies will broaden current concepts about functions of these proteins, and this will be helpful for solution of urgent biomedical problems.

Heterogeneous nuclear ribonucleoproteins (hnRNPs) are structurally and functionally distinct proteins containing specific domains and motifs that enable the proteins to bind certain nucleotide sequences, particularly those found in human telomeres. In human malignant cells (HMCs), hnRNP-A1—the most studied hnRNP—is an abundant multifunctional protein that interacts with telomeric DNA and affects telomerase function. In addition, it is believed that other hnRNPs in HMCs may also be involved in the maintenance of telomere length. Accordingly, these proteins are considered possible participants in the processes associated with HMC immortalization. In our review, we discuss the results of studies on different hnRNPs that may be crucial to solving molecular oncological problems and relevant to further investigations of these proteins in HMCs.

Comparative proteomic studies of proteins in DU-145, PC-3, LNCaP and BPH-1 cultivated cells as well as in prostate tissue samples obtained from patients with benign and malignant tumors showed differences in protein profiles, in particular, high content in tissue samples of four isoforms of transgelin and profilin-1. Increased expression of protein Dj-1 was observed in cancer cells and biopsy samples of prostate cancer as opposed to BPH-1 cells and biopsy samples of tissues with benign hyperplasia. Dramatic reduction of serpin H1 was noted in the range of cell lines: BPH-1 → РС-3 → DU-145 → LNCaP. Thus, the obtained data are indicative of protein Dj-1 and serpin H1 participation in formation of the cancer phenotype in prostate cells.