一種檢測(cè)細(xì)胞中蛋白質(zhì)和脂質(zhì)量的新技術(shù)可幫助外科醫(yī)生發(fā)現(xiàn)肉眼無(wú)法看到的腦腫瘤組織。目前，腦手術(shù)牽涉到許多的猜測(cè)。因?yàn)楹茈y區(qū)分腦腫瘤與正常腦組織，神經(jīng)外科醫(yī)生常常在手術(shù)時(shí)依賴像組織顏色和質(zhì)地等可見(jiàn)的線索。在許多手術(shù)中，本來(lái)可以被安全去除的腫瘤組織卻意外地被留了下來(lái)。由Daniel Orringer及其同事研發(fā)的新技術(shù)依靠拉曼光譜檢測(cè)法，它能通過(guò)檢測(cè)化學(xué)鍵的振動(dòng)來(lái)對(duì)組織中的脂質(zhì)和蛋白質(zhì)的豐富程度進(jìn)行測(cè)繪。腫瘤有著相對(duì)較高含量的蛋白及相對(duì)較低的脂質(zhì)，而正常腦組織則兩者皆含量豐富。Orringer及其同事應(yīng)用一種特殊的高功率類型的拉曼光譜檢測(cè)法——叫做受激拉曼散射或SRS，它能讓研究人員快速地對(duì)小鼠中的腦腫瘤成像。

　　為了給圖像添加色彩，研究人員對(duì)拉曼信號(hào)進(jìn)行編碼——使脂質(zhì)呈綠色，蛋白呈藍(lán)色，因此腫瘤看上去大多呈藍(lán)色而正常組織則顯示大量的綠色。正如所料，他們看到癌細(xì)胞在組織中緊密地?cái)D在一起并觀察到束狀的軸突——即長(zhǎng)的纖維狀的神經(jīng)元——會(huì)像高速公路那樣幫助癌細(xì)胞在大腦的各處穿行。研究人員還在腦手術(shù)時(shí)將SRS應(yīng)用于活體小鼠并展示，SRS可在活體腦的區(qū)域中給腫瘤成像，而在這些區(qū)域中腫瘤組織對(duì)肉眼來(lái)說(shuō)看上去是正常的。在腫瘤與正常組織之間的邊緣地帶，研究人員看到有細(xì)胞（推測(cè)是腫瘤細(xì)胞）向正常腦組織滲透。Orringer及其同事目前正在構(gòu)建一種基于SRS成像的牙刷大小的手持式探頭，神經(jīng)外科醫(yī)生在手術(shù)時(shí)有可能會(huì)無(wú)需除去組織而對(duì)腦組織進(jìn)行分析。

生物谷推薦的英文摘要

Sci. Transl. Med. DOI: 10.1126/scitranslmed.3005954

Rapid, Label-Free Detection of Brain Tumors with Stimulated Raman Scattering Microscopy

Minbiao Ji1,*, Daniel A. Orringer2,*, Christian W. Freudiger1, Shakti Ramkissoon3,4, Xiaohui Liu5, Darryl Lau2, Alexandra J. Golby5,6, Isaiah Norton5, Marika Hayashi4, Nathalie Y. R. Agar5,6, Geoffrey S. Young6, Cathie Spino7, Sandro Santagata3, Sandra Camelo-Piragua8, Keith L. Ligon3,4,9, Oren Sagher2 and X. Sunney Xie1,?

Surgery is an essential component in the treatment of brain tumors. However, delineating tumor from normal brain remains a major challenge. We describe the use of stimulated Raman scattering (SRS) microscopy for differentiating healthy human and mouse brain tissue from tumor-infiltrated brain based on histoarchitectural and biochemical differences. Unlike traditional histopathology, SRS is a label-free technique that can be rapidly performed in situ. SRS microscopy was able to differentiate tumor from nonneoplastic tissue in an infiltrative human glioblastoma xenograft mouse model based on their different Raman spectra. We further demonstrated a correlation between SRS and hematoxylin and eosin microscopy for detection of glioma infiltration (κ = 0.98). Finally, we applied SRS microscopy in vivo in mice during surgery to reveal tumor margins that were undetectable under standard operative conditions. By providing rapid intraoperative assessment of brain tissue, SRS microscopy may ultimately improve the safety and accuracy of surgeries where tumor boundaries are visually indistinct.