Distinctive Molecular Abnormalities in Benign and Malignant Skin Lesions: Studies by Raman Spectroscopy

Abstract

Near-infrared Fourier transform Raman spectroscopy is an analytical, nondestructive technique that provides information about the molecular structure of the investigated sample. The molecular structure of proteins and lipids differ between neoplastic and normal tissues and therefore Raman spectroscopy has been considered promising for the diagnosis of cancer. We aimed to compare the molecular structure of normal skin, benign and malignant skin lesions by the near-infrared Fourier transform Raman spectroscopy. Biopsies were obtained from the following skin lesions: skin tag, dermatofibroma, seborrhoeic keratosis, actinic keratosis, keratoacanthoma, basal cell carcinoma, squamous cell carcinoma, nevus intradermalis, nevus compositus, dysplastic nevus and lentigo maligna. Control skin was harvested from the vicinity of these lesions. In the Raman spectra, the secondary structure of the proteins was reflected by the amide vibrations of peptide bonds. The principal lipid vibrations were twisting and wagging (CH2) and CH stretching vibrations. Histologically distinguishable lesions showed specific combinations of band changes indicating alterations in the protein conformation and in the molecular structure of the lipids. Histogenetically related lesions (actinic keratosis and sqamous cell carcinoma) produced similar but not identical patterns of spectral changes. Because the examined skin lesions produced reproducible and unique spectra, we suggest that Raman spectroscopy will be useful for diagnosis of skin lesions.

Raman spectroscopy can differentiate malignant tumors from normal breast tissue and detect early neoplastic changes in a mouse model

“…Mastitis is characterized by destruction of mature adipose tissue with sheets of inflammatory cells and foamy macrophages. Raman spectra of mastitis (Figure 2d) lacked the phospholipid peak at 1747 cm 21 and showed superimposed peaks in the 1200-1500 cm 21 region, resulting in a noticeably broad spectral feature.…”

“…Other studies have also shown the ability of Raman spectroscopy to accurately classify diseased tissue in brain, 16,17 skin, [18][19][20][21][22][23][24] cervix, [25][26][27] breast, 1,2,9,10,28-33 and other organs. 8,11,[34][35][36][37][38][39][40][41][42][43][44] Our data is confirmatory, and, in addition, demonstrates changes in the tumor bed, which probably represent the detection of chemical signs of preneoplastic changes.…”

Classification of colonic tissues using near-infrared Raman spectroscopy and support vector machines

“…In the past decade, optical spectroscopic methods such as Raman spectroscopy have been comprehensively investigated for cancer and precancer diagnosis and evaluation (3)(4)(5)(6)(7)(8)(9)(10)(11)(12). Raman spectroscopy measures inelastic light scattering and is a vibrational spectroscopic technique that can provide specific spectroscopic fingerprints based on the molecular composition and structures of biological tissues (3,4,(8)(9)(10).…”

A study examining the effects of tissue processing on human tissue sections using vibrational spectroscopy

“…Raman however, has the advantage of minimal interference from water so is a good choice for biological samples with a view to in vivo measurements. Some of the tissue types examined by various groups include; cervical [2][3][4], breast [5][6][7], skin [8][9][10][11][12], lung [13], brain [14,15] bladder [16], esophagus [17][18][19], colon [20], liver [21,22], thyroid [23] and prostate [24,25]. A variety of different methods of sample preparation have been employed in these studies, such as; fresh, frozen, airdried, formalin-fixed and de-waxed formalin fixed paraffin preserved (FFPP) tissue sections.…”