Terahertz Characterization of Ordinary and Aggressive Types of Oral Squamous Cell Carcinoma as a Function of Cancer Stage and Treatment Efficiency

Oral squamous cell carcinoma (OSCC) has asymptomatic characteristics that make it challenging to identify in the early stages and lead to metastatic effects. Terahertz (THz) spectroscopy and imaging are recognized as novel techniques for early cancer detection due to their nonionizing nature, the significant THz wave absorption by water's hydrogen bonds, and the higher hydration of tumors. Despite this potential, there is a lack of research on the THz characterization of oral cancer with various essential biological conditions. THz characterization based on frozen, freshly excised tissue restricts parametric studies on important components and diverse biological situations. Therefore, we cultivated the 3-D, organotypic model of the OSCC, to investigate the THz spectroscopy of the tumor at various phases and the effects of the anticancer drug AG1478 on its THz spectra. Moreover, we have compared the characterization of OSCC with two levels of aggressiveness and we contrasted how well the medication worked on these two types of cell lines. The measurements were performed at the frequency range of 0.4-1.6 THz, and with increasing malignancy of the samples, we observed higher refractive index, absorption coefficient, and complex permittivity than normal tissue. The results demonstrate that although AG1478 shifts the THz spectra in the direction of the normal tissue, it has no effect on aggressive OSCC (AOSCC) under the same circumstances. These findings may contribute to techniques that diagnose and detect tumors at the early stage.

Automated summary

Oral squamous cell carcinoma (OSCC) is difficult to identify in early stages and often leads to metastasis due to its asymptomatic characteristics. Terahertz (THz) spectroscopy and imaging have been recognized as novel techniques for early cancer detection, as they are nonionizing and have significant THz wave absorption by water's hydrogen bonds and higher hydration in tumors. However, there is a lack of research on THz characterization of oral cancer. In this study, a 3-D organotypic model of OSCC was cultivated to investigate the THz spectroscopy of the tumor at various phases and the effects of the anticancer drug AG1478 on its THz spectra. The results show that AG1478 has an effect on shifting the THz spectra towards normal tissue, but has no effect on aggressive OSCC (AOSCC). These findings may contribute to early-stage tumor diagnosis and detection techniques.