001, 41 patients) [16]. Silvia et al. and Joshi et al. showed similar significant

results for sialic acid overexpression in oral cancer patients [17] and [18] Specific glycan changes can be targeted using lectins. Lectins are proteins or glycoproteins of non-immune origin that bind non-covalently to specific oligosaccharide chains extending extracellularly from glycoproteins or glycolipids [19]. Lectins exhibit high specificity in recognizing their specific sugar moieties, and thus are useful analytical tools to study the alterations in cell surface carbohydrates in diseased stages [15], [19], [20] and [21]. The other advantages of using lectin probes are the ease of production due to their abundance, inexpensiveness, ease of labeling with fluorescent probes, PD-166866 mw heat stability, stability at low pH, and low toxicities as many are part of the normal human diet [22]. As sialic acid residues are overexpressed during carcinogenesis, an appropriate lectin probe specific to sialic acid could provide an advantageous biomarker for oral cancer

detection. One particular lectin of interest is the legume wheat germ agglutinin (WGA), which click here is a carbohydrate-binding lectin of approximately 36 kDa that selectively recognizes sialic acid and N-acetylglucosaminyl sugar residues [11], [14] and [22]. Furthermore, conjugation of this lectin with a fluorophore could provide an effective non-invasive in vivo screening method to visualize premalignant and malignant oral lesions

in real time. The objective of our study was to establish a preclinical screening technique that targets an intrinsic fluorophore, nicotinamide adenine during dinucleotide (NAD+/NADH), and sialic acid expression, using fluorescent conjugated WGA, to screen for oral cancers. This proof-of-concept preclinical study will be used to guide later clinical evaluation studies. Freshly extracted tissue samples were obtained either from patients diagnosed with oral cancer or from scalpel biopsies acquired from patients suspected of having oral cancer. In addition, punch biopsies were acquired from patients suspected to have oral cancer, which entered the study via the walk-in clinic. All seven patients gave their written informed consent to participate, and the study was reviewed and approved by the Institutional Review Boards at the University of Minnesota and the Mazumdar Shaw Cancer Center in Bangalore, India. Paired biopsies of clinically normal and abnormal oral mucosa were acquired with patient morbidity in mind, and did not deviate from normal clinical practice ( Figure 1). Normal tissue biopsies either came from tissue adjacent to the surgical margin or from a slight extension of suspicious lesion margin ( Figure 1). Upon extraction, tissue samples were placed in 1 × phosphate buffered saline (PBS) (Sigma Aldrich, Milwaukee, WI) to prevent dehydration and then were immediately used for testing. All materials were used as received, unless noted otherwise.