Lactotransferrin expression is downregulated and affects the mitogen-activated protein kinase pathway in gastric cancer
Authors: Yanhong Zhou
Wei Yi
Hong Yi
Gengqiu Luo
Journal: Oncology Letters (2015)
Discipline: CLINICAL MEDICINE
Keywords: expression; gastric cancer; lactotransferrin; mitogen-activated protein kinase.
Affiliations: Department of Pathology, Xiangya Hospital, Central South University, Changsha, Hunan 410008, P.R. China., Molecular Genetics Laboratory, Cancer Research Institute, Central South University, Changsha, Hunan 410078, P.R. China., Research Center of Carcinogenesis and Targeted Therapy, Xiangya Hospital, Central South University, Changsha, Hunan 410008, P.R. China.

Abstract:  Gastric cancer (GC) is the second leading cause of cancer-associated mortality worldwide. In advanced and metastatic GC, conventional chemotherapy results in limited efficacy and the average survival rate is currently approximately 10 months. Dysregulated activation of numerous genes, including zinc finger, DHHC-type containing 14; caspase-associated recruitment domain-containing protein; and Ras association domain family member 10, have been implicated in GC. The tumor suppressor function of lactotransferrin (LTF) has been reported in a variety of tumors, including GC, nasopharyngeal carcinoma (NPC) and prostate cancer. However, the mechanism of the tumor suppressor function of LTF in GC remains unclear. In the present study, the expression levels of LTF in patient GC tissue samples were investigated using reverse transcription-quantitative polymerase chain reaction, and it was demonstrated that the LTF mRNA expression level in GC tissue samples was reduced by ~20-fold compared with the adjacent non-cancerous tissues (t=4.56, P&lt;0.01). A similar trend in LTF protein expression was observed by western blot analysis. Furthermore, the present study demonstrated that the mitogen-activated protein kinase (MAPK) signaling pathway intermediates p38, c-Jun N-terminal kinase (JNK) and c-Jun were highly expressed in GC tissue samples, and indicated that LTF downregulation may be associated with the dysregulation of the MAPK signaling pathway in GC tissues. In addition, the present study indicated that LTF overexpression reduced the expression of p38, JNK2 and c-Jun in the GC cell line, SGC7901. The present study demonstrates that LTF expression is downregulated in GC tissues and that LTF may serve an important role in the dysregulation of the MAPK signaling pathway. 

Retracted: No

PubPeer comments:
 This paper was found during a systematic search of papers in this journal with possible duplicated images. About 15% of the papers in this journal (n=98 examined) were found to contain inappropriately duplicated images. These papers have all been reported to the journal publisher in 2017. The editors promised to  investigate promptly but no action has been taken as of today. Figure 4. Blue boxes highlight two panels representing different proteins that look unexpectedly similar to each other.  , 
 Corrigendum: [1 February 2021] . ------------------------------------------------- Following the publication of the above article, an interested reader drew to the authorsu2019 attention that, in Fig. 4 on p. 2412, the data intended to show the p38 and JNK2 protein bands were apparently the same. The authors reu2011examined their original data, and realized that the JNK2 data had inadvertently been inserted into the Figure twice. The corrected version of Fig. 4, showing the correct data for the p38 protein bands, is shown opposite. Note that the correction made to this figure does not affect the overall conclusions reported in the paper. The authors are grateful to the Editor of Oncology Letters for granting them the opportunity to publish this corrigendum, and apologize to the readership for any inconvenience caused. , 
 Thank you for the update, Hoya. The  interested reader (me) was not notified by the journal publisher (Spandidos) of this update. So I appreciate it that you updated it here. I reported this paper to the publisher in September 2017. ,