Circulating tumor cells (CTCs) are among the earliest signs of metastasis or cancer spread in the body [1]. Thus, their detection can help catch metastasis early and treat it early. However, due to their rarity, and light and sound absorption by the skin, CTCs are difficult to detect in vivo.

Now, could CTCs be detected in the superficial mucus tissue in the mouth? In the shallow depth of the lower lip, both ultrasound and optical imaging can be used to image cells inside venules (small vessels) [2], [3], making the lower lip a perfect candidate for photoacoustic imaging (PAI) of CTCs. We aim to make a simplified in-vitro model of the lower lip and image flowing melanoma CTCs inside it using PAI.

A similar situation exists in the colorectum tissue, on a different scale: from cells to small tumors. We are working with the Netherlands Cancer Institute (NKI) in Amsterdam to detect colorectal tumors. As a response to therapy, many times, a colorectal tumor fragments into pieces [4]. Again, the mucus tissue in the colorectum allows us to monitor these tumor fragments using PAI [5].

Therefore, the core idea of this project is to develop and test a photoacoustic microscope (PAM) for (1) the detection of melanoma CTCs in an in-vitro flow setup, resembling the human’s lower lip, and (2) the detection of tumor and tumor fragments in ex-vivo colorectum tissue.

Key tasks

• Designing and assembling a photoacoustic microscope (PAM) for cell and tissue measurements
• Characterizing ex-vivo colorectum samples (and/or microtissues grown from cells) with the PAM
• Detecting a flowing melanoma cell inside an in-vitro flow model of the lower-lip
• Outlying a preliminary and creative design of an in-vivo sensor for the lower lip and the colorectum (potential for future funding)

You will have access to equipment, devices, and samples to assemble the PAM and carry out the measurements. This project is in collaboration with the Netherlands Cancer Institute, and the AMBER group and the AST group at University of Twente. Besides access to medical and cell-research facilities, working with these institutes will expand your collaborative and scientific network.

References

[1] Dasgupta, Arko, Andrea R. Lim, and Cyrus M. Ghajar. "Circulating and disseminated tumor cells: harbingers or initiators of metastasis?." Molecular oncology 11.1 (2017): 40-61.

[2] Winer, Matan M., et al. "In vivo noninvasive microscopy of human leucocytes." Scientific Reports 7.1 (2017): 13031.

[3] Ghanbarzadeh-Dagheyan, Ashkan, et al. "Time-domain ultrasound as prior information for frequency-domain compressive ultrasound for intravascular cell detection: A 2-cell numerical model." Ultrasonics 125 (2022): 106791.

[4] Ghanbarzadeh-Daghyean, Ashkan, et al. "Application of a Photoacoustic Sensor for Colon Cancer Imaging: A Case Report." 2023 IEEE SENSORS. IEEE, 2023.

[5] Nagtegaal, I. D. & Glynne-Jones, R. How to measure tumour response in rectal cancer? An explanation of discrepancies and suggestions for improvement. Cancer Treat. Rev. 84, 101964 (2020).

• A PhD (or MSc.) in physics, biomedical engineering, biomedical imaging or a related field;
• Knowledge and experience with photoacoustic and/or ultrasound imaging;
• A can-do attitude and considering research challenges as opportunities;
• Experience with coding in MATLAB (or Python);
• Good communication and teamwork skills, with good command of English;
• Self-motivation and strong interest in carrying out collaborative and independent research.

• A full-time position for 18 months, and the flexibility to work (partially) from home;
• Your salary and associated conditions are in accordance with the collective labour agreement for Dutch universities (CAO-NU);
• You will receive a gross monthly salary ranging from € 3.226,- to € 5.090,- (salary scale 10) based on education and work experience;
• There are excellent benefits including a holiday allowance of 8% of the gross annual salary, an end-of-year bonus of 8.3%, and a solid pension scheme;
• A minimum of 232 leave hours in case of full-time employment based on a formal workweek of 38 hours. A full-time employment in practice means 40 hours a week, therefore resulting in 96 extra leave hours on an annual basis;
• Free access to sports facilities on campus;
• A family-friendly institution that offers parental leave (both paid and unpaid);
• Excellent career support and courses for your professional and personal development.

At BMPI, we investigate the use of light for medical purposes. Our aim is to develop optical and hybrid optical-acoustical technologies for medical research and diagnosis, in particular in the fields of oncology, wound healing and microscopy. Physiological properties of primary interest to us are microcirculatory blood flow, hemoglobin concentrations, blood oxygenation and scattering properties in general.

Our approaches include physical research into light-tissue interaction and its measurement, biomedical engineering to realize suitable instrumentation for ex-/in-vivo use, and clinical evaluation together with several medical partners.