# Status Quo of Glycoslation in Cancer: What Is, What Is Not and What Is to Be
## 2 Milestones of Glycoslation in Cancer
### Glycosylation for Cancer Biomarkers
have published an overview of the glycosylation-linked biomarkers in their detailed review [75]. Pancreatic adenocarcinoma is a deadly form of cancer with a 5-year survival rate of \(<\)5%. Its diagnosis consists of imaging and tissue biopsy and complete surgical resection is the only curative therapy. Pancreatic cancer metastases early and mostly patients are diagnosed when treatment is not possible. Carbohydrate antigen CA 19-9, sLeA is the most established biomarker for this form of cancer. Other markers include truncated O-glycans (Tn and sTn), elevated sialyl Lewis X antigen (sLex), branched and fucosylated N-glycans, upregulated proteoglycans and galectins and elevated O-GlcNAcylation [109]. Glycoslation is reported to be instrumental for androgen control in prostate cancer cells. Eight glycosylation enzymes (GALNT7, UAP1, GCNT1, PGM3, ST6 GalNAc1, ST6 GAL1, CSGALNACT1 and EDEM3) are significantly upregulated in prostate cancer. These 8 enzymes are under an androgen receptor (AR) and are reported by [PERSON] to be linked to cancer-related sialyl-Tn (sTn), sialyl LewisX (SLEx), O-GlcNAc and chondro sulfate. AR as well as glycosylation is reported to be mediated by androgens in prostate cancer cells [110]. Importantly, AR regulates key glycosylation enzymes and synthesis of several cancer-linked glycans in prostate cancer [111]. Epithelial ovarian malignancy is the fifth most common disease in women, having the highest death rate. The membrane glycosylation of non-carcinogenic ovarian surface epithelial (HOSE 6.3 and HOSE 17.1) and serous ovarian disease cell lines (SKOV 3, IGROV1, A2780, OVCAR 3), have been contemplated. Proof has been published [112] that MGAT3 articulation might be epigenetically controlled by DNA hypomethylaltion, bringing about the one of a kind \"bisecting GlcNAc\" type N-glycans on the membrane proteins of ovarian cancer cells. Glycoenzymes as a therapeutics target for cancer patients are also under consideration [113] Glycoprotein comprise of protein tumor markers endorsed by the Food and Drug Administration (FDA), and are being applied into clinical practices. The FDA endorsed biomarkers include: MUC-1 (CA15-3/CA27.29) [114] and plasminogen activator inhibitor (PAI-1) [115], beta-human chorionic gonadotropin (Beta-hCG) [116], the biomarker of breast cancer; AFP; biomarkers of colorectal cancer [117], biomarkers of liver cancer and germ cell cancer, chromogranin A (CgA) [118], biomarkers of neuroendocrine cancer and MUC16 (CA-125) [119] and HE4 [120], biomarkers of ovarian cancer [121]. The molecular evidence of aberrant glycosylation in colorectal cancers (CRC) was explored. [PERSON] et al., focused on re-sequencing of 430 glycosylation-related genes in patient-derived CRC cell lines and matched primary tumor tissues. They reported changes in 12 new glycosylation-related genes in colon disease [122]. Enrichment of mutations in B3 GNT2, B4 GALT2, ST6 GALNAC2 genes associated with the biosynthesis of N-and O-linked glycans in the colon was reported. They concluded that deleterious mutations in glycosyltransferase genes are linked to aberrant glycosylation and impact on colon and other gastrointestinal cancers. It is accepted that the acknowledgment of the widespread pertinence of glycosylation to the cancer hallmarks will progressively affect disease treatment through the advancement of new efforts to treat cancer [123]. At present, most cancer treatment protocols include radiotherapy, medical procedures, and chemotherapy. Endeavors are in progress for recognizing compelling cutting edge therapies to supplant conventional strategies [124; 125]. Production of anticancer therapeutic proteins as a class of medications is dominant in the medication business, due to advances in recombinant DNAinnovation [126]. Glycosylation plays a crucial role in recombinant anticancer therapeutic proteins, as most of the approved recombinant therapeutics are glycoproteins. Various methodologies have been adopted to design the Golgi's N-glycosylation pathway to obtain human-like glycans.