N-Glycomic Changes in Human Breast Carcinoma MCF-7 and T-Lymphoblastoid Cells After Treatment with Herceptin and Herceptin/Lipoplex

Abstract

The humanized monoclonal antibody IgG1 in combination with chemotherapy has been demonstrated to enhance survival benefit in cancer treatment. Despite positive outcomes, some cancer cells develop multidrug resistance. Numerous mechanisms in cancers can be involved in the process of treatment therapy and most of them are not still well understood. To address how the carbohydrate moieties of cells are affected during treatment, the glycan profiles from the two most common cancer cell lines s human breast MCF-7 carcinoma and T-lymphoblastoid CEM cells s were studied here and compared with profiles after treatment with Herceptin alone or in combination with Lipofectamine mixed with plasmid DNA to form Lipoplex. N-Glycans were released from total cells by digestion with PNGaseF and analyzed by matrix-assisted laser desorption ionization mass spectrometry (MALDI-MS). In summary, both original cell lines showed a dominant occurrence of high-mannose glycans. After treatment, these structures were suppressed and biantennary core-fucosylated glycans originating from IgG1 were the major carbohydrate products identified in cells. The high incidence of additional fucosylated or nonfucosylated galactosylated oligosaccharides, which were not detected in original cells or Herceptin, varied with conditions and time of exposure of cells to the antibody. The results presented in this study provide strong evidence for a role of glycosylation during antibody treatment.

Online enzymatic sequencing of glycans from Trastuzumab by phospholipid‐assisted capillary electrophoresis

“…1B for glycan structures). These glycans were also detected in Trastuzumab using a different methodology [57]. Although glycan standards can be utilized to confirm structure in capillary electrophoresis, the cost and limited commercial availability make it impractical to use glycan standards to probe structural characteristics.…”

Functional roles of glycogene and N‐glycan in multidrug resistance of human breast cancer cells

“…Kudo et al (13) showed that N-glycan alterations were associated with drug resistance in human hepatocellular carcinoma. Lattova et al (14) reported that N-glycomic changes in human breast carcinoma MCF-7 and T-lymphoblastoid cells occurred after treatment with herceptin and herceptin/Lipoplex. Our results also showed that glycomic alterations were associated with MDR in human leukemia (15).…”

Alterations in Glycopeptides Associated with Herceptin Treatment of Human Breast Carcinoma MCF-7 and T-Lymphoblastoid Cells

“…Thus, the same batch of Herceptin used for treatment in our study underwent a thorough analysis of glycans, as reported previously (19). Furthermore, a detailed analysis of glycopeptides obtained from the antibody is presented here along with the investigation of glycosylated peptides isolated from treated samples, to validate the profiles observed.…”

“…Both types of these experiments showed also differences at the proteome level. The monitoring of N-glycans in cancer cells before and after exposure to the antibody showed significant alterations in glycosylation (19). Dominant high-mannose glycans (Man 5-9 GlcNAc 2 ) accompanied by less abundant of fucosylated tri-and tetrantennary higher sialylated glycans were found in both original cancer cells and after treatment these structures were replaced by complex biantennary fucosylated oligosaccharides of the same compositions as found in IgG1.…”

“…We recently demonstrated how the carbohydrate moieties of two cancer cell models were affected during treatment with antibody (19). The detailed glycans profiles studied by means of mass spectrometry (MS) from the two most common cancer cell lines-human breast MCF-7 carcinoma and T-lymphoblastoid CEM cells before and after treatment with Herceptin showed significant differences.…”