Ubiquitous Neural Cell Adhesion Molecule (NCAM): Potential Mechanism and Valorisation in Cancer Pathophysiology, Drug Targeting and Molecular Transductions

Neural cell adhesion molecule, an integrated molecule of immunoglobulin protein superfamily involved in cell-cell adhesion, undergoes various structural modifications through numerous temporal-spatial regulations that generously alter their expressions on cell surfaces. These varied expression patterns are mostly envisioned in the morphogenesis and innervations of different human organs and systems. The considerable role of NCAM in neurite growth, brain development and etc. and its altered expression of NCAM in proliferating tumour cells and metastasis of various human melanomas clearly substantiate its appropriateness as a cell surface marker for diagnosis and potential target for several therapeutic moieties. This characteristic behaviour of NCAM is confined to its novel biochemistry, structural properties, signalling interactions and polysialylation. In particular, the characteristic expressions of NCAM are mainly attributed by its polysialylation, a post-translational modification that attaches polysialyl groups to the NCAM. The altered expression of NCAM on cell surface develops curiosity amidst pharmaceutical scientists, which drives them to understand its role of such expressions in various human melanomas and to elucidate the promising therapeutic strategies that are currently available to target NCAM appositely. Therefore, this review article is articulated with an insight on the altered expressions of NCAM, the clinical significances and the consequences of such atypical expression patterns in various human organs and systems.

How Schwann cells facilitate cancer progression in nerves

Recent studies have demonstrated a critical role for nerves in enabling tumor progression. The association of nerves with cancer cells is well established for a variety of malignant tumors, including pancreatic, prostate and the head and neck cancers. This association is often correlated with poor prognosis. A strong partnership between cancer cells and nerve cells leads to both cancer progression and expansion of the nerve network. This relationship is supported by molecular pathways related to nerve growth and repair. Peripheral nerves form complex tumor microenvironments, which are made of several cell types including Schwann cells. Recent studies have revealed that Schwann cells enable cancer progression by adopting a de-differentiated phenotype, similar to the Schwann cell response to nerve trauma. A detailed understanding of the molecular and cellular mechanisms involved in the regulation of cancer progression by the nerves is essential to design strategies to inhibit tumor progression.

Evaluation of the inferior and superior laryngeal nerve stumps for perineural spread in laryngeal cancer

Objective

Perineural spread (PNS) is an important risk factor for locoregional failure and is correlated with reduced survival rates in squamous cell carcinoma of the larynx. PNS may extend proximally and/or distally in the nerve sheath by leaving unin-volved nerve segments. This method of extension may preclude obtaining tumor-free surgical margins, which may be responsible for recurrent disease. The purpose of this study is to investigate the presence or absence of PNS in extralaryngeal superior and inferior laryngeal nerves in patients who underwent total laryngectomy for squamous cell carcinoma of the larynx.

METHODS

Extralaryngeal segments of superior and inferior laryngeal nerves were resected bilaterally during 15 consecutive laryngectomies. Laryngectomy specimens and the harvested proximal nerve segments were histopathologically examined for the presence or absence of PNS.

RESULTS

Ten of 15 laryngectomy specimens showed PNS; however, none of the extralaryngeal superior or inferior laryngeal nerve segments revealed perineural involvement.

CONCLUSION

Extralaryngeal extension of PNS is highly unlikely in squamous cell carcinoma of the larynx.