謝曉冬,郭 放 ,韓雅玲
乳腺癌是女性最常見的惡性腫瘤之一。據(jù)美國2014年最新統(tǒng)計(jì),其發(fā)病人數(shù)為232 670例,發(fā)病率位居女性惡性腫瘤首位;死亡人數(shù)為40 000例,病死率僅次于肺癌,位居次席[1]。中國是乳腺癌發(fā)病率增長較快的國家之一,在城市女性中發(fā)病率僅次于宮頸癌,位居第二位[2]。近年來我國乳腺癌發(fā)病率逐年增高,現(xiàn)已成為城市人口死亡率增長最快的癌癥,且發(fā)病年齡呈年輕化趨勢,防控形勢極為嚴(yán)峻。隨著醫(yī)學(xué)基因檢測技術(shù)和現(xiàn)代分子生物學(xué)的發(fā)展,人們對乳腺癌的發(fā)病機(jī)理、預(yù)防方法和治療手段等有了更深層次的認(rèn)識,同時(shí)在此基礎(chǔ)上研制新藥并探索新方法,將其在臨床推廣應(yīng)用,因而從基礎(chǔ)到臨床的“轉(zhuǎn)化性研究新理念”應(yīng)運(yùn)而生,在近年學(xué)術(shù)年會(huì)上多次成為研究和談?wù)摰臒狳c(diǎn)[3]。
本課題組進(jìn)行了乳腺癌微轉(zhuǎn)移基因篩查,包括探索血管內(nèi)皮生長因子家族(VEGFs)、人乳腺珠蛋白基因(hMAM)、乳腺上皮粘蛋白(small breast epithelial mucin,SBEM)、轉(zhuǎn)移黏附基因(MTDH)和細(xì)胞周期素G1(cyclin G1)等在乳腺癌形成和發(fā)展過程中的重要作用[4-8]。同時(shí)開展乳腺癌術(shù)后患者生活質(zhì)量評估,將基礎(chǔ)研究與臨床應(yīng)用相結(jié)合,提升了乳腺癌的診斷準(zhǔn)確率和治療有效率。本文從轉(zhuǎn)化醫(yī)學(xué)角度闡述乳腺癌基礎(chǔ)研究到臨床應(yīng)用的轉(zhuǎn)化過程,分別從基因分型指導(dǎo)臨床診治、微轉(zhuǎn)移篩查預(yù)測患者預(yù)后和生活質(zhì)量評估改善患者生存質(zhì)量三個(gè)方面進(jìn)行分析探討,初步認(rèn)識乳腺癌轉(zhuǎn)化醫(yī)學(xué)新理念。
經(jīng)臨床驗(yàn)證,乳腺癌是一種異質(zhì)性較強(qiáng)的惡性腫瘤,它在組織形態(tài)、免疫表型和生物學(xué)行為等方面差異極大,表現(xiàn)為雖然具有相同的病理分期,但臨床療效和預(yù)后可能差異較大[9]。目前,人們從基礎(chǔ)研究中發(fā)現(xiàn)一些特定的分子受體(如ER、PR、HER-2和Ki-67)對預(yù)測乳腺癌的復(fù)發(fā)轉(zhuǎn)移風(fēng)險(xiǎn)及診治效果具有重要意義,并在臨床上通過基因芯片技術(shù)和免疫組織化學(xué)方法對其聯(lián)合檢測,根據(jù)設(shè)定的標(biāo)準(zhǔn)將乳腺癌劃分為4類特定的分子亞型,見表1,具有指導(dǎo)臨床診治的重大價(jià)值[10]。不同分子亞型的乳腺癌患者臨床治療手段不同,Luminal A型僅適用于以他莫昔芬、依西美坦等藥物為代表的內(nèi)分泌治療,而Luminal B型患者需要在內(nèi)分泌治療基礎(chǔ)上聯(lián)合化療,其中HER-2陽性患者還應(yīng)聯(lián)合曲妥珠單抗治療。在HER-2過表達(dá)型乳腺癌治療方面,常規(guī)化療基礎(chǔ)上加用曲妥珠單抗不僅可改善客觀緩解率(ORR)和中位無進(jìn)展生存期(PFS),同時(shí)可提高總生存率(OS)[11-13]。目前,曲妥珠單抗聯(lián)合化療已成為HER-2陽性乳腺癌的一線治療標(biāo)準(zhǔn),H0648g、M77001、CHAT等多項(xiàng)研究相繼證實(shí)曲妥珠單抗能為患者帶來更長的生存期和更好的生活質(zhì)量[14-16]。Basal-like(基底樣)型乳腺癌與三陰乳腺癌類似且部分重疊,約占全部乳腺癌的10% ~15%,預(yù)后差,5年生存率不到15%。其多見于絕經(jīng)前年輕患者,易出現(xiàn)內(nèi)臟轉(zhuǎn)移和腦轉(zhuǎn)移。由于基因受體表型均為陰性,因此常規(guī)內(nèi)分泌治療和曲妥珠單抗靶向治療療效甚微,治療上主要以蒽環(huán)類化療為主,療效較差且易出現(xiàn)耐藥[17-18]?;谝陨细攀觯橄侔┗蚍中驮谥笇?dǎo)臨床診治方面取得了重要突破,這是將基礎(chǔ)研究轉(zhuǎn)化為臨床應(yīng)用的典型案例,強(qiáng)調(diào)了轉(zhuǎn)化研究的重要意義,但對于特殊亞型的患者,探索性轉(zhuǎn)化研究仍在繼續(xù)。
乳腺癌是一種全身性疾病,其中乳腺癌細(xì)胞的全身播散和轉(zhuǎn)移是引起死亡的主要原因[19]。乳腺癌在早期即可發(fā)生微轉(zhuǎn)移,微轉(zhuǎn)移是乳腺癌發(fā)生播散和轉(zhuǎn)移的根源,是獨(dú)立的不良預(yù)后因素。因此早期檢測出微轉(zhuǎn)移的存在,對乳腺癌的早期診斷、治療以及提高生存率至關(guān)重要,故以 VEGFs、hMAM、SBEM、MTDH和cyclin G1為研究重點(diǎn),探索乳腺癌微轉(zhuǎn)移的發(fā)生、形成機(jī)制和干預(yù)、預(yù)測方法。本文主要對SBEM和cyclin G1的研究進(jìn)展進(jìn)行概述,為后續(xù)文章拋磚引玉。
表1 乳腺癌的基因分子分型
2002年,SBEM首次由Miksicek等報(bào)道,利用表達(dá)序列同位素標(biāo)記技術(shù)和基因表達(dá)序列分析,其為一種低分子量的唾液酸糖蛋白,僅在乳腺和唾液腺組織中表達(dá),具有高度特異性[20]。Skliris等[21]應(yīng)用組織芯片技術(shù)發(fā)現(xiàn)SBEM能夠鑒別預(yù)后較差的特定類型的乳腺癌患者,被認(rèn)為是一個(gè)較好的乳腺癌候選分子標(biāo)志物。而cyclin G1基因見于1993年,由Tamura等在鼠成纖維細(xì)胞中尋找新的Src家族成員過程中發(fā)現(xiàn),定位于染色體5q32-q34區(qū)域,其通過與MDM2、PP2A等分子相互作用,參與了細(xì)胞多種生物學(xué)過程[22]。此外,研究發(fā)現(xiàn)它與抑癌基因p53關(guān)系密切,兩者相互結(jié)合可形成交互負(fù)反饋調(diào)節(jié),提示該分子的異常表達(dá)可能在腫瘤發(fā)生發(fā)展中起到了重要作用[23]。上述基因的基礎(chǔ)研究為人類了解乳腺癌的本質(zhì)提供了可靠數(shù)據(jù),為探尋新的藥物治療靶點(diǎn)提供了研究方向,為開啟乳腺癌轉(zhuǎn)化研究提供了理論基礎(chǔ),臨床應(yīng)用前景廣闊。
隨著科學(xué)的發(fā)展、醫(yī)療技術(shù)的進(jìn)步,乳腺癌病死率顯著降低,長期生存的乳腺癌患者大幅增加。人們對健康的要求不斷提高,患者不僅關(guān)心疾病能否治愈,同時(shí)也注重自身生活質(zhì)量,這已成為臨床診治的關(guān)注熱點(diǎn)[24]。由于生活質(zhì)量是一種生命狀態(tài)及治療效果的評價(jià)技術(shù),一定程度上影響了醫(yī)療決策的選擇、藥物效應(yīng)的評價(jià)及患者病情的預(yù)后,因此如何對其進(jìn)行合理有效評估一直是醫(yī)學(xué)界的熱議話題。目前,國內(nèi)外關(guān)于生活質(zhì)量的評估大多應(yīng)用調(diào)查問卷、自我測評的模式,但獲得的信息相對局限,準(zhǔn)確性和真實(shí)性不佳[25-27]。宋樹璽等將通過查閱的大量文獻(xiàn),自制涵蓋患者本人、配偶和主治醫(yī)生的三方調(diào)查問卷,首次提出多途徑、多角色進(jìn)行生活質(zhì)量調(diào)查問卷的評估模式,研究結(jié)果值得期待。
轉(zhuǎn)化醫(yī)學(xué)作為一個(gè)新名詞,1996年首次見于《Lancet》雜志,它作為基礎(chǔ)研究到臨床應(yīng)用的連接紐帶,在醫(yī)學(xué)科研領(lǐng)域發(fā)揮著愈加重要的作用。人們利用現(xiàn)有技術(shù)可將基礎(chǔ)研究成果轉(zhuǎn)化為臨床應(yīng)用的產(chǎn)品,同時(shí)進(jìn)行合理的臨床觀察有助于人們更好的認(rèn)識疾病本質(zhì),從而進(jìn)行更優(yōu)化的實(shí)驗(yàn)設(shè)計(jì)來促進(jìn)基礎(chǔ)研究,最終促進(jìn)醫(yī)學(xué)的發(fā)展,實(shí)現(xiàn)醫(yī)療診治水平的提高。
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