Aberrant CCR4 expression is involved in tumor invasion of lymph node-negative human gastric cancer
Authors: Chengjun Zhou
Yongmei Yang
Chuanxin Wang
Ailin Qu
Xiaoyun Yang
Xin Zhang
Lutao Du
Journal: PLoS ONE (2015)
Discipline: Multidisciplinary
Keywords: Cellular chemotaxis; chemokine receptors; tumor metastasis; CCR4 expression profiles; histologically node-negative
Affiliations: Department of Clinical Laboratory, Qilu Hospital, Shandong University, Jinan, Shandong Province, China., Department of Gastroenterology, Qilu Hospital, Shandong University, Jinan, Shandong Province, P.R. China., Department of Digestive Disease, The Second Hospital, Shandong University, Jinan, Shandong, P.R. China.

Abstract:  Cellular chemotaxis is the best-known function of chemokine receptors which are closely linked with tumor metastasis. In fact, positive expression of chemokine receptors could also be identified even in some patients without metastatic tumors, while the clinical relevance of this data has not been fully established. Our studies were designed to clarify the CCR4 expression profiles and to explore its potential role in histologically node-negative (pN0) gastric cancer (GC). Immunohistochemistry (IHC) or immunohistofluorescence (IHF) analysis was performed on specimens obtained from 108 patients with pN0 GC. We found that CCR4 was aberrantly over-expressed inpN0 GC tissues, with different expression patterns on tumor cells and being associated with T-stage (P = 0.002). The matrigel in vitro invasion assay revealed that over-expression of CCR4 in GC cell lines significantly enhanced the invasive capacity of these cells. Results from real-time RT-PCR and gelatinzymography showed a significant increase in matrix metalloproteinase (MMP)-9 production induced by the forced expression of CCR4 in GC cell lines. Our data suggest that the aberrant CCR4 expression is involved in tumor invasion of pN0 GC and, conceivably, antagonists of CCR4 might be useful candidates for controlling early events in tumor progression. 

Retracted: Yes

PubPeer comments:
 Concern about Figure 4D: An area of possible overlap appears to be visible between the BGC-823 MOCK and CCR4 panels. Shown with dark blue boxes. ![file] , 
 Figure 4D suffers from additional problems, e.g. the Mock panels contain duplicated areas with the overlapping areas differing only in rotation AND slight rescaling ![file] , 
 at least 3 of the 4 panels in Fig 4 are from the same larger image ![file] , 
 Retraction, December 2020, https: journals.plos.org plosone article?id=10.1371 journal.pone.0244287  Following the publication of this article [1], concerns were raised regarding the results presented in Fig. 4. Specifically, * The BGC-823 MOCK panel of Fig. 4D partially overlaps with the BGC-823 CCR4 panel of Fig. 4D. * The BGC-823 MOCK panel of Fig. 4D partially overlaps with the SGC-7901 MOCK panel of Fig. 4D when rotated. The authors stated that the similarity observed between the panels described above are the result of inadvertent errors introduced during figure preparation and provided data underlying their published results. However, these did not resolve the serious concerns regarding the handling of the data obtained during this study and the integrity of the published results. In light of the concerns affecting multiple figure panels that question the integrity of these data, the PLOS ONE Editors retract this article. YY and CW did not agree with the retraction. LD, XY, AQ, XZ, and CZ either did not respond directly or could not be reached. ,