Cancer cells display high rates of glycolysis even under normoxia and mostly under hypoxia. Warburg proposed this
effect of altered metabolism in cells more than 80 years ago. It is considered as a hallmark of cancer. Optical
spectroscopy can be used to explore this effect.
Pathophysiological studies indicate that mitochondria of cancer cells are enlarged and increased in number. Warburg
observed that cancer cells tend to convert most glucose to lactate regardless of the presence of oxygen. Previous
observations show increased lactate in breast cancer lines.
The focus of this study is to investigate the relative content changes of lactate and mitochondria in human cancerous and
normal breast tissue samples using optical spectroscopic techniques. The optical spectra were obtained from 30
cancerous and 25 normal breast tissue samples and five model components (Tryptophan, fat, collagen, lactate and
mitochondrion) using fluorescence, Stokes shift and Raman spectroscopy. The basic biochemical component analysis
model (BBCA) and a set of algorithm were used to analyze the spectra.
Our analyses of fluorescence spectra showed a 14 percent increase in lactate content and 2.5 times increase in
mitochondria number in cancerous breast tissue as compared with normal tissue. Our findings indicate that optical
spectroscopic techniques may be used to understand Warburg effect. Lactate and mitochondrion content changes in
tumors examined using optical spectroscopy may be used as a prognostic molecular marker in clinic applications.