Elucidating the role of excision repair cross-complement group 1 in oral epithelial dysplasia and early invasive squamous cell carcinoma: An immunohistochemical study

Comparative evaluations of different surgical and non-surgical treatment methods for early invasive and micro invasive squamous cell carcinoma in the oral and maxillofacial regions: A systematic review

OBJECTIVES

The pathogenesis and progressive behavior of head, neck, oral and maxillofacial (HNOMF) squamous cell carcinoma (SCC) has been suggested to be a multistep and multifactorial procedure that necessitates epithelial hyperplasia, epithelial dysplasia, micro invasive squamous cell carcinoma (MISCC) and early invasive squamous cell carcinoma (EISCC); EISCC and MISCC might have a completely different behavior and development process. There are only a limited number of reported HNOMF cases of EISCC or MISCC. There are still no guidelines for the treatment of EISCC and MISCC lesions in the HNOMF regions.

MATERIAL AND METHODS

This systematic review was conducted to gather all surgical and non-surgical treatments for EISCC and MISCC lesions in the HNOMF. The study question according to the PICO format was as followed: clinical and histopathological results (O) of all types of treatments (I) for patients with EISCC and MISCC lesions in HNOMF (P) compared to untreated lesions (C). Medline, Scopus, and Google Scholar were searched and the search was limited to English-language.

RESULTS

Eight clinical human studies were included. Photodynamic therapy (PDT) after topical application of methyl aminolevulinate (MAL-PDT) and topical Imiquimod 5 % cream both had remarkable outcomes.

CONCLUSIONS

However, due to the very limited number of studies conducted on the treatment methods of MISCC and EISCC in the HNOMF regions, further studies are necessary to provide reliability for non-surgical treatment methods.

Targeting DNA damage response as a potential therapeutic strategy for head and neck squamous cell carcinoma

Cells experience both endogenous and exogenous DNA damage daily. To maintain genome integrity and suppress tumorigenesis, individuals have evolutionarily acquired a series of repair functions, termed DNA damage response (DDR), to repair DNA damage and ensure the accurate transmission of genetic information. Defects in DNA damage repair pathways may lead to various diseases, including tumors. Accumulating evidence suggests that alterations in DDR-related genes, such as somatic or germline mutations, single nucleotide polymorphisms (SNPs), and promoter methylation, are closely related to the occurrence, development, and treatment of head and neck squamous cell carcinoma (HNSCC). Despite recent advances in surgery combined with radiotherapy, chemotherapy, or immunotherapy, there has been no substantial improvement in the survival rate of patients with HNSCC. Therefore, targeting DNA repair pathways may be a promising treatment for HNSCC. In this review, we summarized the sources of DNA damage and DNA damage repair pathways. Further, the role of DNA damage repair pathways in the development of HNSCC and the application of small molecule inhibitors targeting these pathways in the treatment of HNSCC were focused.