MilliporeSigma
  • ST6GalNAc-I promotes lung cancer metastasis by altering MUC5AC sialylation.

ST6GalNAc-I promotes lung cancer metastasis by altering MUC5AC sialylation.

Molecular oncology (2021-04-02)
Imayavaramban Lakshmanan, Sanjib Chaudhary, Raghupathy Vengoji, Parthasarathy Seshacharyulu, Satyanarayana Rachagani, Joseph Carmicheal, Rahat Jahan, Pranita Atri, Ramakanth Chirravuri-Venkata, Rohitesh Gupta, Saravanakumar Marimuthu, Naveenkumar Perumal, Sanchita Rauth, Sukhwinder Kaur, Kavita Mallya, Lynette M Smith, Subodh M Lele, Moorthy P Ponnusamy, Mohd W Nasser, Ravi Salgia, Surinder K Batra, Apar Kishor Ganti
ABSTRACT

Lung cancer (LC) is the leading cause of cancer-related mortality. However, the molecular mechanisms associated with the development of metastasis are poorly understood. Understanding the biology of LC metastasis is critical to unveil the molecular mechanisms for designing targeted therapies. We developed two genetically engineered LC mouse models KrasG12D/+ ; Trp53R172H/+ ; Ad-Cre (KPA) and KrasG12D/+ ; Ad-Cre (KA). Survival analysis showed significantly (P = 0.0049) shorter survival in KPA tumor-bearing mice as compared to KA, suggesting the aggressiveness of the model. Our transcriptomic data showed high expression of N-acetylgalactosaminide alpha-2, 6-sialyltransferase 1 (St6galnac-I) in KPA compared to KA tumors. ST6GalNAc-I is an O-glycosyltransferase, which catalyzes the addition of sialic acid to the initiating GalNAc residues forming sialyl Tn (STn) on glycoproteins, such as mucins. Ectopic expression of species-specific p53 mutants in the syngeneic mouse and human LC cells led to increased cell migration and high expression of ST6GalNAc-I, STn, and MUC5AC. Immunoprecipitation of MUC5AC in the ectopically expressing p53R175H cells exhibited higher affinity toward STn. In addition, ST6GalNAc-I knockout (KO) cells also showed decreased migration, possibly due to reduced glycosylation of MUC5AC as observed by low STn on the glycoprotein. Interestingly, ST6GalNAc-I KO cells injected mice developed less liver metastasis (P = 0.01) compared to controls, while colocalization of MUC5AC and STn was observed in the liver metastatic tissues of control mice. Collectively, our findings support the hypothesis that mutant p53R175H mediates ST6GalNAc-I expression, leading to the sialyation of MUC5AC, and thus contribute to LC liver metastasis.

MATERIALS
Product Number
Brand
Product Description

Sigma-Aldrich
Anti-Mucin MUC5AC Antibody, clone CLH2, clone CLH2, Chemicon®, from mouse
Sigma-Aldrich
Anti-β-Actin antibody, Mouse monoclonal, clone AC-15, purified from hybridoma cell culture
Sigma-Aldrich
Duolink® In Situ Red Starter Kit Mouse/Rabbit