Lipid quantification by Raman microspectroscopy as a potential biomarker in prostate cancer

Abstract

Metastatic castration recurrent prostate cancer (mCRPC) remains incurable and is one of the leading causes of cancer-related death among American men. Therefore, detection of prostate cancer (PCa) at early stages may reduce PCa-related mortality in men. We show that lipid quantification by vibrational Raman Microspectroscopy and Biomolecular Component Analysis may serve as a potential biomarker in PCa. Transcript levels of lipogenic genes including sterol regulatory element-binding protein-1 (SREBP-1) and its downstream effector fatty acid synthase (FASN), and rate-limiting enzyme acetyl CoA carboxylase (ACACA) were upregulated corresponding to both Gleason score and pathologic T stage in the PRAD TCGA cohort. Increased lipid accumulation in late-stage transgenic adenocarcinoma of mouse prostate (TRAMP) tumors compared to early-stage TRAMP and normal prostate tissues were observed. FASN along with other lipogenesis enzymes, and SREBP-1 proteins were upregulated in TRAMP tumors compared to wild-type prostatic tissues. Genetic alterations of key lipogenic genes predicted the overall patient survival using TCGA PRAD cohort. Correlation between lipid accumulation and tumor stage provides quantitative marker for PCa diagnosis. Thus, Raman spectroscopy-based lipid quantification could be sensitive and reliable tool for PCa diagnosis and staging.

Fourier transform infrared and Raman‐based biochemical profiling of different grades of pure foetal‐type hepatoblastoma

“…Fourier‐transform infrared (FTIR) spectroscopy and Raman spectroscopy, as label‐free and high‐throughput vibrational spectroscopic methods, are two powerful complementary bioanalytical tools to probe secondary structure, dynamics, solvation and interactions of biomolecules . Bands in infrared (IR) or Raman spectra are molecule‐specific and offer unique information about biochemical composition of analysed samples .…”

“…These bands are relatively narrow and sensitive to molecular vibrations. The shift of the bands and the changes in band intensity provide the opportunity to distinguish different classes at the molecular level . In combination with chemometric methods, such as principal component analysis plus linear discriminant analysis (PCA‐LDA), FTIR and Raman spectroscopic analyses have recently shown great promise as a means to facilitate biomarker discovery, sample clustering and classification from spectral datasets .…”

“…The shift of the bands and the changes in band intensity provide the opportunity to distinguish different classes at the molecular level . In combination with chemometric methods, such as principal component analysis plus linear discriminant analysis (PCA‐LDA), FTIR and Raman spectroscopic analyses have recently shown great promise as a means to facilitate biomarker discovery, sample clustering and classification from spectral datasets . In particular, both FTIR and Raman spectroscopies have been successfully applied in the field of biological and clinical researches, such as environmental toxicology, epigenetics, pathology, laboratory diagnosis and cytology .…”

“…As the development and progression of cancer are accompanied by the structural and compositional changes of biological tissues, both FTIR and Raman spectroscopies can be used to distinguish normal and cancerous cells in different organs and to track the overall biochemical changes during the malignant transformation process . Recently, FTIR and Raman techniques have been developed to enable the identification of malignant phenotypes in a high‐sensitivity, real‐time and noninvasive way .…”

“…For instance, Aubertin et al developed a method of ex vivo tissue characterisation using Raman spectroscopy that made it possible to perform in vivo diagnosis and guide surgical resection during radical prostatectomy procedures for prostate cancer . Furthermore, O'Malley et al suggested that Raman spectroscopy‐based lipid quantification could be applied for diagnostics and prognostics of prostate cancer . Using confocal Raman spectroscopy in an ex vivo setting, Liu et al reported that the subcellular Raman approach is a promising clinical tool for colon cancer diagnosis .…”