title: Decreased expression of Rab27A and Rab27B correlates with metastasis and poor prognosis in colorectal cancer.
abstract: The Rab27 subfamily of secretory small GTPase plays a vital role in vesicle trafficking and regulates tumor growth and metastasis in several cancer types. Thus, this research was designed to explore the clinical and prognostic significance of Rab27A and Rab27B in colorectal cancer (CRC) patients. Reverse transcription-polymerase chain reaction (RT-PCR), western blot, and immunohistochemistry (IHC) analysis were used to examine Rab27A and Rab27B expression in human CRC cell lines and primary tumors. The correlation of gene expression with clinicopathological features and prognosis was also evaluated. Our results indicated that Rab27A expression was down-regulated in primary tumors compared with matched adjacent tissues (100%, 8/8), as detected by western blot. IHC analysis revealed that the positive expression rate of Rab27A in primary CRC tissues was lower than in adjacent normal tissues (P = 0.005). Negative expression of Rab27A and Rab27B significantly correlated with poor tumor differentiation (both P < 0.001) and positive vascular invasion (P = 0.005, P = 0.021, respectively). Moreover, absence of Rab27A was associated with advanced tumor node metastasis (TNM) stage (P = 0.006), distant metastasis (P = 0.002), and local recurrence (P = 0.038). Survival analysis also showed a significant correlation between unfavorable survival and negative expression of Rab27A (P = 0.002). In addition, positive expression of both Rab27A and Rab27B was a protective factor in CRC. In conclusion, decreased expression of Rab27A and Rab27B, especially Rab27A, closely correlated with tumor progression and are valuable prognostic indicators in CRC patients.
authors.affiliation: Department of Oncology, The First Affiliated Hospital, General Hospital of Chinese People's Liberation Army, Beijing 100048, China.|Department of Oncology, General Hospital of Chinese People's Liberation Army, Beijing 100853, China.|These authors contributed equally to this article.
authors.forename: Weiwei
authors.initials: W
authors.lastname: Dong
authors.affiliation: Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education/Beijing), Laboratory of Molecular Oncology, Peking University Cancer Hospital and Institute, Beijing 100142, China.|These authors contributed equally to this article.
authors.forename: Jiantao
authors.initials: J
authors.lastname: Cui
authors.affiliation: Department of Oncology, The First Affiliated Hospital, General Hospital of Chinese People's Liberation Army, Beijing 100048, China.|These authors contributed equally to this article.
authors.forename: Jingwen
authors.initials: J
authors.lastname: Yang
authors.affiliation: Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education/Beijing), Laboratory of Molecular Oncology, Peking University Cancer Hospital and Institute, Beijing 100142, China.
authors.forename: Wenmei
authors.initials: W
authors.lastname: Li
authors.affiliation: Cancer Center, Beijing Shijitan Hospital, Capital Medical University, Beijing 100038, China.
authors.forename: Shuo
authors.initials: S
authors.lastname: Wang
authors.affiliation: Inner Mongolia Medical University, Inner Mongolia Autonomous Region, China.
authors.forename: Xiaojuan
authors.initials: X
authors.lastname: Wang
authors.affiliation: Cancer Center, Beijing Shijitan Hospital, Capital Medical University, Beijing 100038, China.
authors.forename: Xing
authors.initials: X
authors.lastname: Li
authors.affiliation: Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education/Beijing), Laboratory of Molecular Oncology, Peking University Cancer Hospital and Institute, Beijing 100142, China.
authors.forename: Youyong
authors.initials: Y
authors.lastname: Lu
authors.affiliation: Department of Oncology, The First Affiliated Hospital, General Hospital of Chinese People's Liberation Army, Beijing 100048, China.
authors.forename: Wenhua
authors.initials: W
authors.lastname: Xiao
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D045744:Cell Line, Tumor; D015179:Colorectal Neoplasms / Q000235:genetics* / Q000473:pathology*; D005260:Female; D020869:Gene Expression Profiling; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D009362:Neoplasm Metastasis; D011379:Prognosis; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D020691:rab GTP-Binding Proteins / Q000235:genetics* / Q000378:metabolism; D000075745:rab27 GTP-Binding Proteins
chemical_list: D012333:RNA, Messenger; D000075745:rab27 GTP-Binding Proteins; C066694:RAB27A protein, human; C512960:Rab27B protein, human; D020691:rab GTP-Binding Proteins