Prognostic Value and Clinical Significance of Lncrna SNHG7 in Human Cancers: A Meta Analysis Volume 5 - Issue 1

Yulu Zhang^1,2, Gang Liu^1,3, Qing Deng^1,3, Cong Li^1,2 and Zhi Hua Li^1,3*

• ¹Department of Breast Surgery, Third Hospital of Nanchang, JiangXi Breast Specialist Hospital, Nanchang, People’s Republic of China
• ²Jiangxi Medical College of Nanchang University, Nanchang, People’s Republic of China
• ³Key Laboratory of Breast Diseases in Jiangxi Province, Nanchang, People’s Republic of China

Received: September 05, 2021   Published: September 24, 2021

Corresponding author: Zhi Hua Li, Department of breast, The Third Hospital of Nanchang City, Jiangxi Breast Specialist Hospital, Nanchang, Jiangxi 330009, China

DOI: 10.32474/OAJOM.2021.05.000201

 

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Abstract

Background: SNHG7 is a newly identified lncRNA which can regulate tumour growth and metastasis.However, role of SNHG7 in the the prognosis of various cancers is unclear.The aim of this meta analysis is to summarize the published studies to confirm the roles in tumor prognosis and its clinical significance.
Methods: A literature search of online databases was performed in Pubmed,Web of science and Embase. Pooled HRs and the corresponding 95% CIs for OS ,as well as ORs and the corresponding 95% CIs for TNM stage, histological grade, tumor size, and lymph node metastasis were evaluated.
Results: A total of seventeen studies with 1215 patients were enrolled in the meta analysis.Our results showed that high SNHG7 expression level was associated with an unfavorable OS (HR=2.51, 95% CI: 2.08–3.04) for various tumors. In addition, it was found that increased SNHG7 expression was significantly associated with TNM stage (OR = 3.33; 95% CI:2.55–4.36), tumor size (OR = 2.16; 95% CI:1.61–2.9), lymph node metastasis (OR = 3.84; 95% CI: 2.63–5.6). Nevertheless, there was no significant correlation between High SNHG7 expression level and histological grade (OR=0.75;95% CI:0.51-1.09).
Discussions: High SNHG7 expression is predictive of poor OS, poor TNM stage, larger tumor size, and more lymph node metastasis, which suggests High SNHG7 expression could serve as a independent novel biomarker of poor prognosis in cancer. But, additional studies are needed to validate this observation.

Keywords: Lncrna SNHG7, Clinical Significance, Prognosis, Human Cancer

Introduction

Breast cancer is a common malignant tumor and the main cause of cancer death in women, ranked second only after lung cancer [1]. In 2018, there will be approximately 2.1 million newly diagnosed female breast cancer cases worldwide, accounting for almost a quarter of female cancer cases,and the cause of cancer death of breast cancer is about 11.6% [2]. LncRNAs have been demonstrated to play a key role in several aspects of carcinoma,comprises cell growth, differentiation, apoptosis and migration [3]. In recent years,small nucleolar RNA hostgene 7 (SNHG7),located on the chromosome 9[4], have Received a lot of attention.SNHG7 is associated with invasion and metastasis of various tumors, including breast cancer [5], cervical cancer [6], gastric cancer [4],prostate cancer [7] etc. However, whether SNHG7 can predict the prognosis of various cancers is unclear. In this meta, we summarize recent studies on the role of SNHG7 in cancers, to further analysis of the relationship with prognosis and clinical predictors.

Materials and Methods

Literature Retrieval Strategy

We comprehensively performed a search of EMBASE, PUBMED, WEB OF SCIENCE, from inception to April 2020. The search comprised the following terms:“breast cancer”, “carcinoma”, “SNHG7”, “tumor” and “tumorigenesis”.

Criteria for Inclusion and Exclusion

Eligible literature met the following criteria: (1) contains prognostic value no matter what kind of tumor; (2) provides the KM curve or hazard ratio (HR) of the overall survival rate and its 95% confidence interval; (3) provides odds ratio (OR) for clinic-pathological features; and (4) original research articles. Publications were excluded if they had one or more of the following criteria: (1) focus on animals instead of human; (2) abstract, review, comment, and case reports; (3) absence of survival outcomes, such as the hazard ratio (HR), 95% confidence interval (CI), and P values or OR values.and (4) insuffificient data.

Data Extraction and Quality Assessment

Data extraction and the assessment of quality were conducted independently by 2 investigators. A standardized table was used to record all available information,including (1).baseline information such as author,year,cut-off value,cancer type; (2).HR and its 95%CI; (3) .SNHG7 expression frequencies in different clinic-pathological features (TNM stage, histological grade, tumor size, and lymph node metastasis). For quality assessment of included studies, studies were respectively assessed by utilizing the modified Newcastle- Ottawa Scale (NOS). Any inconsistency was resolved by a senior investigator.

Statistical Analysis

The HR for OS was used as a measure of the relationship between SNHG7 expression and cancer prognosis. We utilized the hazard ratios(HRs) and 95% confidence intervals(CIs) reported in the original study when it was available ,and If not obtained directly from the article, the HR values were extracted from a survival curve through Engauge Digitizer (V.4.1) according the methodology mentioned by Tierney[8]. Odds ratios (ORs) and the corresponding 95% CIs were performed to assess the association between SNHG7 expression and clinic-pathological features, including TNM stage, histological grade, tumor size, and lymph node metastasis. Statistical analysis was performed with Review Manager 5.3 (The Cochrane collaboration, Oxford, UK).

Results

Characteristics of Eligible Studies

As shown in Figure 1,167 articles were initially obtained from Web of Science, PubMed, Embase.Of these, 112 studies were excluded because of duplication. After reading titles and abstracts,10 articles were removed as reviews or irrelevance theme. Then, 45 articles were reviewed in full,and 28 reports were excluded because they were articles lacking prognosis, clinical index,or availvable date. Eventually,17 studies with 1215 patients were included in the meta analysis. Main characteristics and data of articles included in this meta-analysis are described in table 1 and table 2. All articles are from china and were published between 2018 and 2020. The maximum and minimum sample size were 162 and 40, respectively. Of the enrolled studies, A total of 12 cancer types were included in our study: cervical cancer(n=3), hepatocellular carcinoma(n=1), Pancreatic cancer(n=1), hypopharyngeal cancer(n=1), Neuroblastoma(n=1), breast cancer(n=1), bladder cancer(n=2), colorectal cancer(n=2), prostate cancer(n=2),gastric cancer(n=1), Thyroid cancer(n=1),and non-small cell lung cancer(n=1).As the table 3 suggested,according to the modified NOS,All inclued studies got scores of 8 or more, indicating the high methodological quality.

Tissue SNHG7 Level and Overall Survival

Fourteen studies with 1037 patients reported on overall survival[9-22]. There is no heterogeneity among these studies (I2 = 0%, P=0.46). Under the fixed effects model, the HR for OS was 2.51(95%CI=2.08-3.04,P<0.00001), indicating that high SNHG7 predicted poor OS for cancer patients.

Tissue SNHG7 Level and Clinic-Pathological Features

Fourteen studies with 971 patients reported on TNM stage [9, 11-14, 16-24]. There is no heterogeneity among these studies (I2 = 0%, P=0.75). Under the fixed effects model,the OR for TNM stage was 3.33(95%CI=2.55-4.63,P<0.00001), indicating that high SNHG7 predicted poor TNM stage for cancer patients.

Tissue SNHG7 level and Histological Grade

Eight studies with 486 patients reported on histological grade [9, 11-13, 16, 20, 21, 25]. There is no heterogeneity among these studies (I2 = 42%, P=0.1). Under the fixed effects model,the OR for TNM stage was 0.75(95%CI=0.51-1.09,P=0.13), indicating that SNHG7 level had no relation with histological grade.

Tissue SNHG7 level and Tumor Size

Thirteen studies with 809 patients reported on tumor size[9, 11, 12, 15-21, 23-25]. There is no heterogeneity among these studies (I2 = 20%, P=0.25). Under the fixed effects model,the OR for tumor size was 2.16(95%CI=1.61-2.9,P<0.00001), indicating that high SNHG7 predicted larger tumor size for cancer patients.

Tissue SNHG7 Level and Lymph Node Metastasis

sixteen studies with 1135 patients reported on lymph node metastasis[9, 11-25]. There is moderate heterogeneity among these studies (I2 = 46%, P=0.02). Under the random effects model,the OR for lymph node metastasis was 3.84(95%CI=2.63-5.6,P<0.00001), indicating that high SNHG7 predicted more lymph node metastasis for cancer patients.

Discussion

As the incidence of cancer increases, more cancer patients suffer physical and mental damage [1]. Metastasis is the main cause of death of cancer patients, but it’s exact mechanism is still unclear. Recently, researchers have focused on new prognostic molecules markers in order to find specific metastasis mechanisms to enable patients to receive more accurate treatment. As a newly discovered molecule related to tumor prognosis, Chaudhry [26] first reported in 2013 that SNHG7 is a small nucleolar RNA host gene, which is expressed in lymphoblastic cell lines TK6 and wtk1.
Later research has shown that SNHG7 is a key oncogene in many human cancer types, including breast cancer, cervical cancer, hepatocellular carcinoma, Pancreatic cancer, hypopharyngeal cancer, Neuroblastoma, bladder cancer, colorectal cancer, prostate cancer, gastric cancer, Thyroid cancer, non-small cell lung cancer [9- 25, 27]. Rencently, more and more studies reportd the prognostic value of SNHG7 overexpression for different cancers. Zhang, et al [28] reported that High levels lncRNA SNHG7 indicated shorter recurrence and OS time Synchronous Colorectal Liver Metastasis Following Hepatectomy She K, et al [29]. demonstrated that SNHG7 can stimulate the proliferation, migration and invasion of lung cancer cells and suppress their apoptosis by improving FAIM2 expression Guo, et al [30]. suggested that SNHG7 promoted proliferation and migration by sponging miR‐449a in thyroid cancer cells. And other studies demonstrated that SNHG7 accelerate proliferation and tumorigenesis interacting with miR-34a through EMT initiation and the Notch-1 pathway in breast cancer [5,31], through PI3K/Akt/mTOR pathway in colorectal cancer[16],through EMT in osteosarcoma[32], and through EMT in gastric cancer [22]. However, Only one other study hold that SNHG7 curbed malignant transformation in uveal melanoma cells [33]. These studies found that lncRNA SNHG7 may serve as an key prognostic factor in various human rumors. Until now, the underlying regulatory mechanisms by which SNHG7 regulated human cancers and its utility as a biomarker remained unclear. In our meta-analysis, we explored prognostic value and clinical significance of LncRNA SNHG7 in human cancers.
A total of 1215 patients with various cancer from the 17 eligible studies were systematically collected and assessed in this study. High SNHG7 expression is predictive of poor OS, poor TNM stage, larger tumor size, and more lymph node metastasis. Despite our pooled analysis showes a comprehensive study, this meta-analysis has some limitations. Firstly, this study include the small sample size. Secondly, The HR values of only two studies are obtained directly from the text. Thirdly, all included articles are from China. Finally, most of the included articles are retrospective cohort studies. In summary, We suggests that high SNHG7 expression could serve as a independent novel biomarker of poor prognosis in cancer. Additional multicenter prospective studies are required to confirm our results and a more precise molecular mechanism.

Acknowledgements

This work was supported by the National Natural Science Foundation of China (Contract grant numbers: 81860546).

Disclosure Statement

The authors declare no conflict of interests.

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