- 作者列表："Brandt AC","McNally L","Lorimer EL","Unger B","Koehn OJ","Suazo KF","Rein L","Szabo A","Tsaih SW","Distefano MD","Flister MJ","Rigo F","McNally MT","Williams CL
:The chaperone protein SmgGDS promotes cell-cycle progression and tumorigenesis in human breast and nonsmall cell lung cancer. Splice variants of SmgGDS, named SmgGDS-607 and SmgGDS-558, facilitate the activation of oncogenic members of the Ras and Rho families of small GTPases through membrane trafficking via regulation of the prenylation pathway. SmgGDS-607 interacts with newly synthesized preprenylated small GTPases, while SmgGDS-558 interacts with prenylated small GTPases. We determined that cancer cells have a high ratio of SmgGDS-607:SmgGDS-558 (607:558 ratio), and this elevated ratio is associated with reduced survival of breast cancer patients. These discoveries suggest that targeting SmgGDS splicing to lower the 607:558 ratio may be an effective strategy to inhibit the malignant phenotype generated by small GTPases. Here we report the development of a splice-switching oligonucleotide, named SSO Ex5, that lowers the 607:558 ratio by altering exon 5 inclusion in SmgGDS pre-mRNA (messenger RNA). Our results indicate that SSO Ex5 suppresses the prenylation of multiple small GTPases in the Ras, Rho, and Rab families and inhibits ERK activity, resulting in endoplasmic reticulum (ER) stress, the unfolded protein response, and ultimately apoptotic cell death in breast and lung cancer cell lines. Furthermore, intraperitoneal (i.p.) delivery of SSO Ex5 in MMTV-PyMT mice redirects SmgGDS splicing in the mammary gland and slows tumorigenesis in this aggressive model of breast cancer. Taken together, our results suggest that the high 607:558 ratio is required for optimal small GTPase prenylation, and validate this innovative approach of targeting SmgGDS splicing to diminish malignancy in breast and lung cancer.
: 伴侣蛋白SmgGDS促进人乳腺癌和非小细胞肺癌的细胞周期进展和肿瘤发生。SmgGDS的剪接变异体，命名为SmgGDS-607 和SmgGDS-558，通过调节异戊烯化途径通过膜运输促进小gtp酶Ras和Rho家族致癌成员的激活。SmgGDS-607 与新合成的预异戊烯化小gtp酶相互作用，而SmgGDS-558 与异戊烯化小gtp酶相互作用。我们确定癌细胞具有SmgGDS-607:SmgGDS-558 的高比率 (607:558 比率)，并且该升高的比率与乳腺癌患者的存活率降低相关。这些发现表明，靶向SmgGDS剪接以降低 607:558 的比率可能是抑制由小gtp酶产生的恶性表型的有效策略。在这里，我们报道了一种剪接转换寡核苷酸的开发，命名为SSO Ex5，它通过改变SmgGDS pre-mRNA (信使RNA) 中外显子 5 的内含物来降低 607:558 的比例。我们的结果表明，SSO Ex5 抑制Ras、Rho和Rab家族中多种小gtp酶的异戊烯化，抑制ERK活性，导致内质网 (ER) 应激，未折叠蛋白反应，并最终在乳腺癌和肺癌细胞系中凋亡细胞死亡。此外，在MMTV-PyMT小鼠中腹膜内 (i.p.) 递送SSO Ex5 在乳腺中重定向SmgGDS剪接，并减缓乳腺癌的这种侵袭性模型中的肿瘤发生。总之，我们的结果表明，最佳小gtp酶异戊烯化需要高 607:558 的比率，并验证了这种靶向SmgGDS剪接以减少乳腺癌和肺癌恶性肿瘤的创新方法.
METHODS::Pulmonary artery sling is a rare congenital anomaly of the origin and course of the left pulmonary artery. Patients with this condition typically present with respiratory failure in young infancy, and asymptomatic cases are uncommon. We describe the case of an adult patient with a lung adenocarcinoma of the right upper lobe, extending into the hilum and superior mediastinum, and with a previously unknown pulmonary artery sling anomaly. The local invasiveness of the tumor and the peculiar vascular anatomy contributed to a unique surgical scenario, wherein multiple reconstructive procedures were required.
METHODS::Patients with idiopathic pulmonary fibrosis (IPF) have higher risk of developing lung cancer, for example, squamous cell carcinoma (SCC), and show poor prognosis, while the molecular basis has not been fully investigated. Here we conducted DNA methylome analysis of lung SCC using 20 SCC samples with/without IPF, and noncancerous lung tissue samples from smokers/nonsmokers, using Infinium HumanMethylation 450K array. SCC was clustered into low- and high-methylation epigenotypes by hierarchical clustering analysis. Genes hypermethylated in SCC significantly included genes targeted by polycomb repressive complex in embryonic stem cells, and genes associated with Gene Ontology terms, for example, "transcription" and "cell adhesion," while genes hypermethylated specifically in high-methylation subgroup significantly included genes associated with "negative regulation of growth." Low-methylation subgroup significantly correlated with IPF (78%, vs. 17% in high-methylation subgroup, p = 0.04), and the correlation was validated by additional Infinium analysis of SCC samples (n = 44 in total), and data from The Cancer Genome Atlas (n = 390). The correlation between low-methylation subgroup and IPF was further validated by quantitative methylation analysis of marker genes commonly hypermethylated in SCC (HOXA2, HOXA9 and PCDHGB6), and markers specifically hypermethylated in high-methylation subgroup (DLEC1, CFTR, MT1M, CRIP3 and ALDH7A1) in 77 SCC cases using pyrosequencing (p = 0.003). Furthermore, low-methylation epigenotype significantly correlated with poorer prognosis among all SCC patients, or among patients without IPF. Multivariate analysis showed that low-methylation epigenotype is an independent predictor of poor prognosis. These may suggest that lung SCC could be stratified into molecular subtypes with distinct prognosis, and low-methylation lung SCC that significantly correlates with IPF shows unfavorable outcome.
METHODS::The role of Fyn-related kinase (FRK) in malignant tumors remains controversial. Our study investigated the function of FRK in lung cancer. Immunohistochemistry staining and generating a knockout of FRK by CRISPR/Cas9 in H1299 (FRK-KO-H1299) cells were strategies used to explore the role of FRK. Immunohistochemistry staining indicated that FRK expression was elevated in 223 lung cancer tissues compared to 26 distant normal lung tissues. FRK contributed to poor survival status in lung cancer patients and acted as a predictor for poor prognosis of lung cancer. Knockout of FRK by CRISPR/Cas9 markedly inhibited proliferation, invasion, colony formation and epithelial-mesenchymal transition (EMT) process in the lung cancer cell line H1299. Further exploration indicated that FRK-KO damaged the stemness phenotype of H1299 by inhibiting CD44 and CD133 expression. Seahorse detection and a U-13 C flux assay revealed that FRK-KO induced metabolism reprogramming by inhibiting the Warburg effect and changing the energy type in H1299 cells. Epidermal growth factor stimulation recovered the expression of FRK and biological functions, metabolic reprogramming and stemness phenotype of H1299 cells. FRK plays an oncogenic role in lung cancer cells via a novel regulation mechanism of enhancing the stemness of H1299 cells by inducing metabolism reprogramming, which finally promotes EMT and metastasis. Our study also indicates that FRK could be used as a potential therapeutic target for drug development.