Intact (whole) cell MALDI TOF mass spectrometry is a commonly used tool in clinical microbiology for several decades. Recently it was introduced to analysis of eukaryotic cells, including cancer and stem cells. Besides targeted metabolomic and proteomic applications, the intact cell MALDI TOF mass spectrometry provides a sufficient sensitivity and specificity to discriminate cell types, isogenous cell lines or even the metabolic states. This makes the intact cell MALDI TOF mass spectrometry a promising tool for quality control in advanced cell cultures with a potential to reveal batch-to-batch variation, aberrant clones, or unwanted shifts in cell phenotype. However, cellular alterations induced by change in expression of a single gene has not been addressed by intact cell mass spectrometry yet. In this work we used a well-characterized human ovarian cancer cell line SKOV3 with silenced expression of a tumor suppressor candidate 3 gene (TUSC3). TUSC3 is involved in co-translational N-glycosylation of proteins with well-known global impact on cell phenotype. Altogether, this experimental design represents a highly suitable model for optimization of intact cell mass spectrometry and analysis of spectral data. Here we investigated five machine learning algorithms (k-nearest neighbors, decision tree, random forest, partial least squares discrimination, and artificial neural network) and optimized their performance either in pure populations or in two-component mixtures composed of cells with normal or silenced expression of TUSC3. All five algorithms reached accuracy over 90 % and were able to reveal even subtle changes in mass spectra corresponding to alterations of TUSC3 expression. In summary, we demonstrate that spectral fingerprints generated by intact cell MALDI-TOF mass spectrometry coupled to a machine learning classifier can reveal minute changes induced by alteration of a single gene, and therefore contribute to the portfolio of quality control applications in routine cell and tissue cultures.

• Klíčová slova
• Bioinformatics, Biotyping, Cell culture, Intact cell MALDI TOF MS, Machine learning, Quality control, R programming language, TUSC3,
• Publikační typ
• časopisecké články MeSH

Two decades ago, following a systematic screening of LOH regions on chromosome 8p22, TUSC3 has been identified as a candidate tumor suppressor gene in ovarian, prostate and pancreatic cancers. Since then, a growing body of evidence documented its clinical importance in various other types of cancers, and first initial insights into its molecular function and phenotypic effects have been gained, though the precise role of TUSC3 in different cancers remains unclear. As a part of the oligosaccharyltransferase complex, TUSC3 localizes to the endoplasmic reticulum and functions in final steps of N-glycosylation of proteins, while its loss evokes the unfolded protein response. We are still trying to figure out how this mechanistic function is reconcilable with its varied effects on cancer promotion. In this review, we focus on cancer-related effects of TUSC3 and envisage a possible role of TUSC3 beyond endoplasmic reticulum.

• Klíčová slova
• Cancer, Endoplasmic reticulum, Immunoediting, N-Glycosylation, Oncogene, TUSC3, Tumor suppressor,
• MeSH
• endoplazmatické retikulum metabolismus   MeSH
• epigeneze genetická MeSH
• genetické lokusy MeSH
• glykosylace MeSH
• karcinogeneze genetika   metabolismus   patologie   MeSH
• lidé MeSH
• lidské chromozomy, pár 8 MeSH
• membránové proteiny genetika   metabolismus   MeSH
• nádorové buněčné linie MeSH
• nádorové supresorové proteiny genetika   metabolismus   MeSH
• nádory genetika   metabolismus   patologie   MeSH
• orgánová specificita MeSH
• proliferace buněk MeSH
• regulace genové exprese u nádorů * MeSH
• signální dráha UPR MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• přehledy MeSH
• Názvy látek
• membránové proteiny MeSH
• nádorové supresorové proteiny MeSH
• TUSC3 protein, human MeSH Prohlížeč

Prostate cancer is the most prevalent cancer in males in developed countries. Tumor suppressor candidate 3 (TUSC3) has been identified as a putative tumor suppressor gene in prostate cancer, though its function has not been characterized. TUSC3 shares homologies with the yeast oligosaccharyltransferase (OST) complex subunit Ost3p, suggesting a role in protein glycosylation. We provide evidence that TUSC3 is part of the OST complex and affects N-linked glycosylation in mammalian cells. Loss of TUSC3 expression in DU145 and PC3 prostate cancer cell lines leads to increased proliferation, migration and invasion as well as accelerated xenograft growth in a PTEN negative background. TUSC3 downregulation also affects endoplasmic reticulum (ER) structure and stress response, which results in increased Akt signaling. Together, our findings provide first mechanistic insight in TUSC3 function in prostate carcinogenesis in general and N-glycosylation in particular.

• MeSH
• aktivace enzymů MeSH
• endoplazmatické retikulum metabolismus   ultrastruktura   MeSH
• genový knockdown MeSH
• glykosylace MeSH
• hexosyltransferasy chemie   metabolismus   MeSH
• interakční proteinové domény a motivy MeSH
• lidé MeSH
• membránové proteiny chemie   nedostatek   genetika   metabolismus   MeSH
• modely nemocí na zvířatech MeSH
• nádorové buněčné linie MeSH
• nádorové supresorové proteiny nedostatek   genetika   metabolismus   MeSH
• nádory prostaty genetika   metabolismus   patologie   MeSH
• pohyb buněk MeSH
• proliferace buněk MeSH
• protoonkogenní proteiny c-akt metabolismus   MeSH
• regulace genové exprese u nádorů MeSH
• signální transdukce MeSH
• stres endoplazmatického retikula * genetika   MeSH
• tumor burden MeSH
• vazba proteinů MeSH
• viabilita buněk genetika   MeSH
• xenogenní modely - testy protinádorové aktivity MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• mužské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• dolichyl-diphosphooligosaccharide - protein glycotransferase MeSH Prohlížeč
• hexosyltransferasy MeSH
• membránové proteiny MeSH
• nádorové supresorové proteiny MeSH
• protoonkogenní proteiny c-akt MeSH
• STT3B protein, human MeSH Prohlížeč
• TUSC3 protein, human MeSH Prohlížeč