Breast cancer cells exhibits specific dielectric signature in vitro using the open-ended coaxial probe technique from 200 MHz to 13.6 GHz

Abstract

Here we investigated the feasibility of using microwave spectroscopy for characterization of normal and breast cancer cell lines cultured in vitro. Healthy non-tumorigenic, MCF-10A and breast cancer, MDA-MB-231, Hs578T, T47D and MCF-7 cell lines were electrically characterized using the open-ended coaxial probe technique from 200 MHz to 13.6 GHz. The dielectric constant, dielectric loss and conductivity between breast non-tumorigenic and breast cancer cells lines were analyzed and their differences determined. Our results showed that the four breast cancer cell lines analyzed exhibited higher dielectric properties when compared to healthy cells. Interestingly, we found that breast and colon cancer cells have different dielectric properties as well, thus suggesting that each type of cancer has a unique microwave signature. This study shows that microwave characterization of breast cancer cell lines is reliable with potential in biomedical applications such as designing electromagnetic models for detection of tumorous cells in healthy tissues.

Figure 1

Microwave dielectric measurement setup consisting of an open ended coaxial probe, a vector network analyzer (VNA) and an external computer. Microwave signals generated by the VNA were transmitted via the coaxial cable to the probe tip submerged in the sample under test. Signals backscattered from the samples were analyzed using the DAK software installed in the computer to extract the dielectric parameters.

Figure 2

Calibration of measurement setup. Calibration was carried using open, short and load calibration. (a) Represents the open load calibration settings. Result depicted in Smith chart is shown in the upper panel. (b) Represents the short load calibration settings. Result depicted in Smith chart is shown in the upper panel. (c) Represents the load (deionized water) calibration settings. Result depicted in Smith chart is shown in the upper panel.

Figure 3

Morphology of normal and breast cancer cells. Prior to measurement, monolayer grown normal mammary (MCF-10A) and breast cancer cells (MDA-MB-231, Hs578T, MCF-7 and T47-D) cells were observed under EVOS XL Core Cell Imaging System (Life Technologies) at 400x.

Figure 4

Measured dielectric data of breast cell lines with the culture medium. Average values of dielectric constant (a), dielectric loss (b) and conductivity (c) as a function of frequency for each of the prepared samples (normal and cancerous breast cell line) measured with the culture medium. Data are representative of three independent experiments carried out in triplicate.

Figure 5

Measured dielectric data of breast cell lines without the culture media. Average values of dielectric constant (a), dielectric loss (b) and conductivity (c) as a function of frequency for each of the prepared samples (normal and cancerous breast cell line) measured without the culture medium. Data are representative of three independent experiments carried out in triplicate.

Figure 6

Comparison of dielectric properties of colon cancer cell lines and the culture medium. Average values of dielectric constant (a), dielectric loss (b) and conductivity (c) as a function of frequency for each of the prepared samples; samples of HT-29 colon cancer cell line were analyzed with and without the culture medium. Data are representative of three independent experiments carried out in triplicate.

Figure 7

Comparison of dielectric properties of colon and breast cancer cell lines. Average values of dielectric constant (a), dielectric loss (b) and conductivity (c) as a function of frequency for each of the prepared samples of colon and breast cancer cell lines.