-
肺癌是癌症中导致死亡的首要原因[1-2]。约有85%的肺癌患者被诊断为非小细胞肺癌(non-small cell lung cancer,NSCLC),而90%的NSCLC患者病死与肿瘤转移有关[3]。多数NSCLC患者发病时已经发生了多处转移,而未经治疗的转移性患者的中位生存时间仅为4~5个月,1年生存率仅为10%[4]。尽管目前对肺癌转移方面的研究有了新的进展,但肺癌转移患者的预后仍然不乐观。因此,有必要进一步拓宽对NSCLC转移机制的认识,以改善对该病的治疗效果。
放疗被认为是无法进行手术的早期NSCLC患者的主要治疗手段。立体定向放射疗法(stereotactic body radiation therapy,SBRT)可以安全、有效地对无法进行手术的早期NSCLC患者(包括基础肺功能较差的患者)进行治疗[5]。尽管SBRT对早期NSCLC患者的局部控制率很好(3年期为98%、5年期为87%)[6-7],但患者在随访中经常发生远处转移;对于不能手术治疗的Ⅲ期NSCLC患者,化疗联合放疗的试验结果显示,肿瘤控制率或患者生存期并未得到明显改善[8]。因此,目前仍需要探索影响NSCLC辐射敏感性的因素,从而改善NSCLC的放疗效果,特别是在疾病的早期阶段。
富含半胱氨酸型运动神经元蛋白1(cysteine-rich motor neuron 1,CRIM1)是骨形态发生蛋白抑制剂家族中富含半胱氨酸区域的Ⅰ型跨膜糖蛋白,相对分子质量约为130 000,含有1036个氨基酸,由胞质区、跨膜域和胞外域组成。在CRIM1蛋白的羧基末端,有一个跨膜结构域和一个相对较短的胞质区,胞外域包括位于氨基末端的信号肽序列、胰岛素样生长因子结合蛋白样结构域和6个高度保守的富含半胱氨酸的重复序列,胞外域可以从细胞中释放,形成分泌型CRIM1[9-10]。在本研究中,我们通过体内外实验探讨CRIM1对NSCLC辐射敏感性和转移的影响,并初步探索其作用机制。
CRIM1对非小细胞肺癌辐射敏感性和转移的影响
Effects of CRIM1 on radiosensitivity and metastasis of non-small cell lung cancer
-
摘要:
目的 探讨富含半胱氨酸型运动神经元蛋白1(CRIM1)对非小细胞肺癌(NSCLC)辐射敏感性和转移的影响及可能的机制。 方法 采用短发夹RNA(shRNA)敲降NSCLC H460、H358细胞中CRIM1的表达,并将H460、H358细胞分别分为3组:H460细胞、H460-shCRIM1细胞、H460-shNC细胞和H358细胞、H358-shCRIM1细胞、H358-shNC细胞,其中shCRIM1表示用shRNA敲降CRIM1的表达,shNC表示阴性对照。采用小干扰RNA(siRNA)敲降H358细胞中CRIM1的表达,并将细胞分为2组:H358-siNC细胞和H358-siCRIM1细胞。采用细胞克隆形成实验(照射剂量为0、1、2、4 Gy)、慧星实验(照射剂量为8 Gy)和细胞免疫荧光实验(照射剂量为6、8、12 Gy)观察CRIM1对H460细胞辐射敏感性的影响。采用Transwell实验、细胞黏附实验观察CRIM1对H460、H358细胞转移的影响。构建小鼠H460原位肿瘤模型,采用组织病理学检查评估裸鼠肺内原位接种肿瘤转移情况。采用转录组学分析法探讨CRIM1影响NSCLC细胞转移的可能机制。组间比较采用两独立样本t检验。 结果 克隆形成实验结果显示,与H460-shNC细胞相比,1、2 Gy照射后H460-shCRIM1细胞的克隆形成率明显降低 [1 Gy:(87.04±8.04)%对(58.01±4.39)%;2 Gy:(48.23±1.22)%对(31.43±0.08)%],且差异均有统计学意义(t=4.48、19.50,均P<0.05)。慧星实验结果显示,8 Gy照射后H460-shCRIM1细胞的olive尾距长于H460-shNC细胞,且差异有统计学意义(1.27±0.54对1.05±0.42,t=2.14,P<0.05)。细胞免疫荧光实验结果显示,H460-shCRIM1细胞受照后磷酸化组蛋白H2AX foci数多于H460-shNC细胞(6 Gy:14.33±2.81对11.00±3.92;8 Gy:34.00±11.14对21.17±6.15;12 Gy:25.80±3.96对20.17±3.31),且差异均有统计学意义(t=2.45、5.52、2.47,均P<0.05)。Transwell实验结果显示,H460-shCRIM1、H358-shCRIM1细胞的迁移率分别较H460-shNC、H358-shNC细胞明显升高,且差异均有统计学意义(t=4.73、10.19,均P<0.05)。细胞黏附实验结果显示,H460-shCRIM1、H358-shCRIM1细胞的黏附能力分别较H460-shNC、H358-shNC细胞下降,且差异均有统计学意义(t=2.86、3.66,均P<0.05)。组织病理学检查结果显示,原位接种H460-shCRIM1细胞的裸鼠肺内转移灶明显多于H460-shNC细胞。转录组学分析结果显示,筛选出的细胞黏附相关基因连接黏附分子2(JAM2)、连接蛋白3(NECTIN3)和紧密连接蛋白4(CLDN4)在H460-shCRIM1、H358-siCRIM1细胞中的表达均下降;并在体外实验中得到验证,其中,H460-shCRIM1细胞相较于H460-shNC细胞分别下降了86.66%、49.35%、30.27%(t=47.52、7.47、18.98,均P<0.05),H358-siCRIM1细胞相较于H358-siNC细胞分别下降了36.60%、31.70%、50.00%(t=7.40、7.10、16.56,均P<0.05)。 结论 抑制CRIM1可增强NSCLC细胞H460的辐射敏感性,CRIM1可能通过影响肿瘤细胞连接的方式影响NSCLC的转移。 -
关键词:
- 癌,非小细胞肺 /
- 辐射耐受性 /
- 肿瘤转移 /
- 富含半胱氨酸型运动神经元蛋白1
Abstract:Objective To investigate the effects of cysteine-rich motor neuron protein 1 (CRIM1) on radiosensitivity and metastasis of non-small cell lung cancer (NSCLC) and its possible mechanisms. Methods Short hairpin RNA (shRNA) was used to knock down the expression level of CRIM1 in NSCLC cells H460 and H358, and H460 and H358 cells were divided into three groups respectively: H460, H460-shCRIM1, H460-shNC, and H358, H358-shCRIM1, H358-shNC, where shCRIM1 indicates the knockdown of CRIM1 expression level by shRNA and shNC indicates the negative control. Small interfering RNA was used to knock down the expression of CRIM1 in H358 cells, and the cells were divided into two groups: H358-siNC and H358-siCRIM1. Clone formation assay (irradiation dose of 0, 1, 2, and 4 Gy), comet assay (irradiation dose of 8 Gy), and cellular immunofluorescence assay (irradiation dose of 6, 8, and 12 Gy) were used in observing the effect of CRIM1 on the radiosensitivity of H460 cells. Transwell and cell adhesion assays were used in observing the effect of CRIM1 on cell metastasis in vitro. A mouse in situ tumor model was constructed, and the metastasis of tumors inoculated in situ into nude mouse lungs was assessed using histopathological examination, and transcriptomic analysis was used in exploring the possible effects of CRIM1 on the mechanism of NSCLC cell metastasis. Independent samples t-test was used in comparing groups. Results Clone formation assay showed statistically significant differences between the clone formation rates of H460-shNC and H460-shCRIM1 after 1 and 2 Gy of irradiation ((1 Gy: (87.04±8.04)% vs. (58.01±4.39)%, t=4.48, P<0.05; 2 Gy: (48.23±1.22)% vs. (31.43±0.08)%, t=19.50, P<0.05)). The results of comet assay showed that the olive tail moment of H460-shCRIM1 cells after 8 Gy of irradiation was longer than that of H460-shNC cells, and the difference was statistically significant (1.27±0.54 vs. 1.05±0.42, t=2.14, P<0.05). The results of cell immunofluorescence experiments showed that the number of phosphorylated histone H2AX foci was higher in H460-shCRIM1 cells than in H460-shNC after irradiation (6 Gy: 14.33±2.81 vs. 11.00±3.92; 8 Gy: 34.00±11.14 vs. 21.17±6.15; 12 Gy: 25.80±3.96 vs. 20.17±3.31), and the difference was statistically significant (t=2.45, 5.52, 2.47; all P<0.05). Transwell assay showed that the mobility rates of H460-shCRIM1 and H358-shCRIM1 were significantly higher than those of H460-shNC and H358-shNC, respectively, and the differences were statistically significant (t=4.73, 10.19; both P<0.05). The results of cell adhesion assay showed that the adhesion ability of H460-shCRIM1 and H358-shCRIM1 decreased relative to that of H460-shNC and H358-shNC, respectively, and the difference was statistically significant (t=2.86, 3.66; both P<0.05). Histopathological examination results showed the in situ inoculation of H460-shCRIM1 into nude mice. Intrapulmonary metastases of H460-shCRIM1 were more extensive than those in H460-shNC. Transcriptomic analysis showed that the expression levels of the screened cell adhesion-related genes junctional adhesion molecule 2 (JAM2), nectin cell adhesion molecule 3 (NECTIN3), and claudin 4 (CLDN4) decreased in H460-shCRIM1 and H358-siCRIM1, and this result was verified in in vitro experiments. The expression levels in H460-shCRIM1 decreased by 86.66% (JAM2), 49.35% (NECTIN3), and 30.27% (CLDN4) compared with those in H460-shNC (t=47.52, 7.47, 18.98; all P<0.05), and in H358-siCRIM1 decreased by 36.60% (JAM2), 31.70% (NECTIN3), and 50.00% (CLDN4) compared with those in H358-siNC (t=7.40, 7.10, 16.56; all P<0.05). Conclusion The inhibition of CRIM1 enhances the radiosensitivity of NSCLC cells H460, and CRIM1 may influence NSCLC metastasis by affecting tumor cell junctions. -
-
[1] McIntyre A, Ganti AK. Lung cancer—A global perspective[J]. J Surg Oncol, 2017, 115(5): 550−554. DOI: 10.1002/jso.24532. [2] Cao MM, Chen WQ. Epidemiology of lung cancer in China[J]. Thorac Cancer, 2019, 10(1): 3−7. DOI: 10.1111/1759-7714.12916. [3] Herbst RS, Morgensztern D, Boshoff C. The biology and management of non-small cell lung cancer[J]. Nature, 2018, 553(7689): 446−454. DOI: 10.1038/nature25183. [4] Rapp E, Pater JL, Willan A, et al. Chemotherapy can prolong survival in patients with advanced non-small-cell lung cancer—report of a Canadian multicenter randomized trial[J]. J Clin Oncol, 1988, 6(4): 633−641. DOI: 10.1200/jco.1988.6.4.633. [5] Stanic S, Paulus R, Timmerman RD, et al. No clinically significant changes in pulmonary function following stereotactic body radiation therapy for early-stage peripheral non-small cell lung cancer: an analysis of RTOG 0236[J]. Int J Radiat Oncol Biol Phys, 2014, 88(5): 1092−1099. DOI: 10.1016/j.ijrobp.2013.12.050. [6] Onishi H, Shirato H, Nagata Y, et al. Stereotactic body radiotherapy (SBRT) for operable stage I non-small-cell lung cancer: can SBRT be comparable to surgery?[J]. Int J Radiat Oncol Biol Phys, 2011, 81(5): 1352−1358. DOI: 10.1016/j.ijrobp.2009.07.1751. [7] Miyasaka Y, Komatsu S, Abe T, et al. Comparison of oncologic outcomes between carbon ion radiotherapy and stereotactic body radiotherapy for early-stage non-small cell lung cancer[J/OL]. Cancers, 2021, 13(2): 176[2021-01-25]. https://www.mdpi.com/2072-6694/13/2/176. DOI: 10.3390/cancers13020176. [8] Ahn JS, Ahn YC, Kim JH, et al. Multinational randomized phase Ⅲ trial with or without consolidation chemotherapy using docetaxel and cisplatin after concurrent chemoradiation in inoperable stage Ⅲ non-small-cell lung cancer: KCSG-LU05-04[J]. J Clin Oncol, 2015, 33(24): 2660−2666. DOI: 10.1200/jco.2014.60.0130. [9] Wilkinson L, Kolle G, Wen DY, et al. CRIM1 regulates the rate of processing and delivery of bone morphogenetic proteins to the cell surface[J]. J Biol Chem, 2003, 278(36): 34181−34188. DOI: 10.1074/jbc.M301247200. [10] Furuichi T, Tsukamoto M, Saito M, et al. Crim1C140S mutant mice reveal the importance of cysteine 140 in the internal region 1 of CRIM1 for its physiological functions[J]. Mamm Genome, 2019, 30(11/12): 329−338. DOI: 10.1007/s00335-019-09822-3. [11] Hurov KE, Cotta-Ramusino C, Elledge SJ. A genetic screen identifies the triple T complex required for DNA damage signaling and ATM and ATR stability[J]. Genes Dev, 2010, 24(17): 1939−1950. DOI: 10.1101/gad.1934210. [12] Ogasawara N, Kudo T, Sato M, et al. Reduction of membrane protein CRIM1 decreases E-cadherin and increases claudin-1 and MMPs, enhancing the migration and invasion of renal carcinoma cells[J]. Biol Pharm Bull, 2018, 41(4): 604−611. DOI: 10.1248/bpb.b17-00990. [13] Zeng H, Zhang Y, Yi Q, et al. CRIM1, a newfound cancer-related player, regulates the adhesion and migration of lung cancer cells[J]. Growth Factors, 2015, 33(5/6): 384−392. DOI: 10.3109/08977194.2015.1119132. [14] Ponferrada VG, Fan JQ, Vallance JE, et al. CRIM1 complexes with β-catenin and cadherins, stabilizes cell-cell junctions and is critical for neural morphogenesis[J/OL]. PLoS One, 2012, 7(3): e32635[2021-01-25]. https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0032635. DOI: 10.1371/journal.pone.0032635. [15] Feng ZR, Yu QX, Zhang T, et al. Updates on mechanistic insights and targeting of tumour metastasis[J]. J Cell Mol Med, 2020, 24(3): 2076−2086. DOI: 10.1111/jcmm.14931. [16] Bhat AA, Uppada S, Achkar IW, et al. Tight junction proteins and signaling pathways in cancer and inflammation: a functional crosstalk[J/OL]. Front Physiol, 2019, 9: 1942[2021-01-25]. https://www.frontiersin.org/articles/10.3389/fphys.2018.01942/full. DOI: 10.3389/fphys.2018.01942. [17] Rübsam M, Broussard JA, Wickström SA, et al. Adherens junctions and desmosomes coordinate mechanics and signaling to orchestrate tissue morphogenesis and function: an evolutionary perspective[J/OL]. Cold Spring Harb Perspect Biol, 2018, 10(11): a029207[2021-01-25]. https://cshperspectives.cshlp.org/content/10/11/a029207. DOI: 10.1101/cshperspect.a029207. [18] Citi S. The mechanobiology of tight junctions[J]. Biophys Rev, 2019, 11(5): 783−793. DOI: 10.1007/s12551-019-00582-7. [19] Youssef MY, Mohamed MA. Could e-cadherin and CD10 expression be used to differentiate between atypical endometrial hyperplasia and endometrial carcinoma?[J]. Int J Gynecol Pathol, 2019, 38(2): 128−137. DOI: 10.1097/pgp.0000000000000492. [20] Zeisel MB, Dhawan P, Baumert TF. Tight junction proteins in gastrointestinal and liver disease[J]. Gut, 2019, 68(3): 547−561. DOI: 10.1136/gutjnl-2018-316906.