Expression of the Tumor-associated Mucin 1 Epitope Analyzed with the Humanized PankoMab-GEX™ Antibody in Malignant and Normal Tissues of the Head and Neck.
BACKGROUND
During neoplasia, glycosylation changes. In this setting, mucins, especially mucin 1 (MUC1), become carriers for oncofetal carbohydrates and relieve invasive growth. The recently described tumor-associated MUC1 epitope TA-MUC1 is primarily restricted to malignancies and is overexpressed in these tissues. The humanized monoclonal antibody PankoMab-GEX specifically recognizes TA-MUC1.


MATERIALS AND METHODS
Laryngeal cancer specimens (n=125) and normal tissue of head and neck (n=7) were used in this study. Paraffin-embedded sections were incubated with PankoMab-GEX. Staining reaction was carried out using peroxidase (POD) labeling and diaminobenzidine (DAB). Breast cancer tissue was used as positive control and negative control used non-specific mouse IgM. Semi-quantitative evaluation by two independent double-blinded investigators, including a pathologist, used the immunoreactive score (IRS) of Remmele and Stegner.


RESULTS
A total of 31 out of 125 laryngeal cancer specimens were classified as G1. Of these, 22 (71%) were completely negative for TA-MUC1, the remaining 9 showed very weak staining, with an IRS of 2. A total of 94 cases of cancer specimens were classified as G2 and G3; 34 of them were also negative, but 60 had an IRS of up to 9. All investigated normal tissue of the upper aerodigestive tract was completely negative for TA-MUC1.


CONCLUSION
G1 tumors are completely negative or do not reach an IRS relevant range. The finding that G1 tumors are completely negative for TA-MUC1 or have IRS≤2 can be helpful for histopathological examination, especially concerning tumor grading. Therefore, this antibody holds great potential for use as a therapeutic antibody in laryngeal cancer.
['Wiest|Irmi|I|', 'Alexiou|Christoph|C|', 'Friese|Klaus|K|', 'Betz|Peter|P|', 'Tübel|Jutta|J|', 'Goletz|Steffen|S|', 'Dian|Darius|D|', 'Jeschke|Udo|U|']
D061067:Antibodies, Monoclonal, Humanized D000939:Epitopes D005260:Female D006801:Humans D007150:Immunohistochemistry D007822:Laryngeal Neoplasms D008297:Male D018396:Mucin-1 D009333:Neck D060787:Neoplasm Grading
Mucin 1 PankoMab-GEX laryngeal cancer tumor grading