Functional polymorphisms in the CD44 gene and acute myeloid leukemia cancer risk in a Chinese population

CD44: a cancer stem cell marker and therapeutic target in leukemia treatment

CD44 is a ubiquitous leukocyte adhesion molecule involved in cell-cell interaction, cell adhesion, migration, homing and differentiation. CD44 can mediate the interaction between leukemic stem cells and the surrounding extracellular matrix, thereby inducing a cascade of signaling pathways to regulate their various behaviors. In this review, we focus on the impact of CD44s/CD44v as biomarkers in leukemia development and discuss the current research and prospects for CD44-related interventions in clinical application.

Whole genome, exon mutation and transcriptomic profiling of acute myeloid leukemia: A case report

The present study aimed to observe previously unidentified gene mutation and expression profiles associated with acute myeloid leukemia (AML) at the individual level, based on the blood samples of a father-son pair. Genomic DNA and RNA samples from blood serum were collected. Whole-genome sequencing (WGS) and whole-exome sequencing (WES), as well as mRNA sequencing of the son, were performed. For the father's sample, a total of 3,897,164 single nucleotide polymorphisms (SNPs) and 780,834 insertion and deletions (indels) were identified. Regarding amino acid translation, there were 11,316 non-synonymous, 12 stop-loss, 12,033 synonymous, 92 stop-gain SNPs, 63 frameshift insertions, 73 frameshift deletions, 242 non-frameshift insertions, 248 non-frameshift deletions, four stop-gains and two stop-loss for indel variants. Among the AML-related genes that had been previously identified, 14 genes were found in the father's exon region. For WES of the son's DNA, 96,639 SNPs were identified, including 10,504 non-synonymous SNPs. Seven mutant genes were found in sons' exon region compared with 121 AML-related genes. Based on the transcriptomic sequencing, there were 54 differentially expressed mRNAs, including 31 upregulated and 23 downregulated mRNAs. In the exon region, 10,072 SNPs were detected, and different types of alternative splicing in the son's sample were observed. Overall, whole genome, exon mutation and transcriptomic profiling of the present two patients with AML may provide a new insight into the molecular events governing the development of AML.

CD44 polymorphisms and its variants, as an inconsistent marker in cancer investigations

Among cell surface markers, CD44 is considered the main marker for identifying and isolating the cancer stem cells (CSCs) among other cells and has attracted significant attention in a variety of research areas. Many studies have shown the essential roles of CD44 in initiation, metastasis, and tumorigenesis in different types of cancer; however, the validity of CD44 as a therapeutic or diagnostic target has not been fully confirmed in some other studies. Whereas the association of specific single nucleotide polymorphisms (SNPs) in the CD44 gene and related variants with cancer risk have been observed in clinical investigations, the significance of these findings remains controversial. Here, we aimed to provide an up-to-date overview of recent studies on the association of CD44 polymorphisms and its variants with different kinds of cancer to determine whether or not it can be used as an appropriate candidate for cancer tracking.

Apoptosis and genes involved in oral cancer - a comprehensive review

Oral cancers needs relentless research due to high mortality and morbidity associated with it. Despite of the comparable ease in accessibility to these sites, more than 2/3^rd cases are diagnosed in advanced stages. Molecular/genetic studies augment clinical assessment, classification and prediction of malignant potential of oral lesions, thereby reducing its incidence and increasing the scope for early diagnosis and treatment of oral cancers. Herein we aim to review the role of apoptosis and genes associated with it in oral cancer development in order to aid in early diagnosis, prediction of malignant potential and evaluation of possible treatment targets in oral cancer. An internet-based search was done with key words apoptosis, genes, mutations, targets and analysis to extract 72 articles after considering inclusion and exclusion criteria. The knowledge of genetics and genomics of oral cancer is of utmost need in order to stop the rising prevalence of oral cancer. Translational approach and interventions at the early stage of oral cancer, targeted destruction of cancerous cells by silencing or promoting involved genes should be the ideal intervention.

CD markers polymorphisms as prognostic biomarkers in hematological malignancies

The clusters of differentiation (CD) are surface molecules used for immunophenotyping of cells. The expression of CD markers is widely used to classify hematological malignancies, including leukemia and lymphoma. Single nucleotide polymorphisms (SNPs) are crucial genetic changes that can be associated with abnormal expression and function of CD markers. In this paper, we assess the prognostic effect of CD markers’ SNPs in hematological malignancies. Materials and methods and relevant literature was identified by a PubMed search (2001-2019) of English language papers using the following terms: ‘polymorphism’, ‘CD marker’, ‘leukemia’, ‘lymphoma’, ‘prognosis’, ‘CD marker’, and ‘polymorphism’. Many studies have demonstrated the effects of CD markers’ polymorphisms on risk of hematological malignancies. Also, SNPs of CD markers can be related with clinicopathological features, invasiveness, and response to therapy of these disorders. Considering the importance of SNPs in the expressions of CD markers, these genetic changes could be used as potential prognostic biomarkers in hematological malignancies. It is hoped that the evaluation of SNPs in CD markers will enable early diagnosis, prognosis, and detection of response to treatment. However, better understanding of SNPs in CD markers that are involved in hematological malignancies requires further studies on different populations of the worldwide.

Association of Single-Nucleotide Polymorphisms of CD44 Gene with Susceptibility to Breast Cancer in Chinese Women

Background

This study aimed to evaluate the association of CD44 gene single-nucleotide polymorphisms with susceptibility to breast cancer.

Material/Methods

This case-control study included 242 breast cancer patients and 252 normal people without disease. The single-nucleotide polymorphisms of the CD44 gene in the 2 groups were genotyped by PCR-LDR method. The OR and its 95% CI was calculated by chi-square test and logistic regression analysis. The construction of haplotypes and their interaction analysis with relevant factors were carried out by SHEsis and SNPStats online.

Results

The genotype distribution of CC and CT, CC and CC+CT, and CC+CT and TT in rs13347 showed a significant difference between cases and controls, and the difference in distribution of alleles C and T was statistically significant. The genotype and alleles distribution of rs4756195 and rs8193 showed no statistically significant difference (P>0.05). The haplotypes distribution of CAC, CGT, TAC, and TGT showed a significant difference between the 2 groups (P<0.05). The results of analysis of haplotypes and their interactions with relevant factors showed that breast cancer risk in the PR-negative group was significantly higher than that in the PR-positive group (P=0.016). We found an interaction between haplotypes and PR status.

Conclusions

The genotypes CT, CT+TT, TT, and allele T in rs13347 may be risk factors for breast cancer. The haplotype CAC may be a protective factor against breast cancer, and CGT, TAC, and TGT may be risk factors for breast cancer. The PR status interacts with CD44 gene SNP.

Long non-coding RNA TUG1 promotes endometrial cancer development via inhibiting miR-299 and miR-34a-5p

It is generally known that the human genome makes a large amount of noncoding RNAs compared with coding genes. Long non-coding RNAs (lncRNAs) which composed of more than 200 nucleotides have been described as the largest subclass of the non-coding transcriptome in human noncoding RNAs. Existing research shows that lncRNAs exerted biological functions in various tumors via participating in both oncogenic and tumor suppressing pathways. The previous studies indicated that lncRNA taurine upregulated 1 (TUG1) play important roles in the initiation and progression of malignancies. In this study,based on previous research, we investigated the expression and biological role of the lncRNA-TUG1. We analyzed the relationship between lncRNA-TUG1and endometrial carcinoma (EC) in a total 104 EC carcinoma specimens, compared with that in normal tissues. We found that lncRNA-TUG1 expression in cancer tissues was significantly higher than that in adjacent tissues. Through a series of experiments, the results demonstrated that lncRNA-TUG1 enhances the evolution and progression of EC through inhibiting miR-299 and miR-34a-5p.

Quantitative assessment of CD44 genetic variants and cancer susceptibility in Asians: a meta-analysis

CD44 is a well-established cancer stem cell marker playing a crucial role in tumor metastasis, recurrence and chemo-resistance. Genetic variants of CD44 have been shown to be associated with susceptibility to various cancers; however, the results are confounding. Hence, we performed a meta-analysis to clarify these associations more accurately. Overall, rs13347 (T vs. C: OR=1.30, p=<0.004, p_corr=0.032; CT vs. CC: OR=1.29, p=0.015, p_corr=0.047; TT vs. CC: OR=1.77, p=<0.000, p_corr=0.018; CT+TT vs. CC: OR=1.34, p=<0.009, p_corr=0.041) and rs187115 (GG vs. AA: OR=2.34, p=<0.000, p_corr=0.025; AG vs. AA: OR=1.59, p=<0.000, p_corr=0.038; G vs. A allele OR=1.56, p=0.000, p_corr=0.05; AG+GG vs. AA: OR=1.63, p=<0.000, p_corr=0.013) polymorphisms were found to significantly increase the cancer risk in Asians. On the other hand, rs11821102 was found to confer low risk (A vs. G: OR=0.87, p=<0.027, p_corr=0.04; AG vs. GG: OR=0.85, p=<0.017, p_corr=0.01; AG+AA vs. GG: OR=0.86, p=<0.020, p_corr=0.02). Based on our analysis, we suggest significant role of CD44 variants (rs13347, rs187115 and rs11821102) in modulating individual's cancer susceptibility in Asians. Therefore, these variants may be used as predictive genetic biomarkers for cancer predisposition in Asian populations. However, more comprehensive studies involving other cancers and/or populations, haplotypes, gene-gene and gene-environment interactions are necessary to delineate the role of these variants in conferring cancer risk.

Common polymorphisms in CD44 gene and susceptibility to cancer: A systematic review and meta-analysis of 45 studies

CD44 is one of the commonly recognized stem cell markers, which plays a critical role in many cancer related cellular processes. Relationships between CD44 polymorphisms and cancer risk have been widely investigated previously, whereas results derived from these studies were inconclusive and controversial. We conducted present meta-analysis aiming to explore the association between CD44 polymorphisms and cancer risk. We calculated pooled odds ratios (ORs) corresponding with the 95% confidence intervals (CIs) to make the evaluation clear. Embase, Web of Science, PubMed and Cochrane Library databases were retrieved to identify all eligible publications. As a result, a total of 12 publications comprised 25,777 cases and 27,485 controls fulfilled the inclusion criteria. Nevertheless, the pooled analyses suggested that no significant association was uncovered between CD44 (rs10836347, rs11821102, rs13347, rs1425802, rs353639, rs713330 and rs187115) polymorphisms with overall cancer risk. Subsequently, we conducted subgroup analysis for rs13347 polymorphism based on source of control, and we identified a significantly increased cancer risk for the population-based (P-B) group restricted to a recessive model (TT vs. TC+CC: OR = 2.030, 95%CI: 1.163-3.545, PAdjust < 0.001). In conclusion, our meta-analysis demonstrates that CD44 polymorphisms may not represent risk factors for cancer. Future well-designed large-scale case-control studies are warranted to verify our findings.

Associations of five polymorphisms in the CD44 gene with cancer susceptibility in Asians

CD44 polymorphisms have been previously associated with cancer risk. However, the results between independent studies were inconsistent. Here, a meta-analysis was performed to systematically evaluate associations between CD44 polymorphisms and cancer susceptibility. A comprehensive literature search conducted in PubMed, Embase, and Web of Science databases through August 10, 2016 yielded 11 eligible publications consisting of 5,788 cancer patients and 5,852 controls. Overall, odds ratios (OR) calculated with 95% confidence intervals (CI) identified a significant association between CD44 polymorphism rs13347 and cancer susceptibility under all genetic models. Additionally, the minor allele of polymorphism rs11821102 was associated with a decreased susceptibility to cancer in allele contrast, dominant, and heterozygous models, while no significant association was identified for polymorphisms rs10836347, rs713330, or rs1425802. Subgroup analysis by ethnicity revealed rs13347 was significantly associated with cancer susceptibility for Chinese but not for Indians. Linkage disequilibrium (LD) between different polymorphisms varied across diverse ethnic populations. In conclusion, the results indicate that CD44 polymorphism rs13347 acts as a risk factor for cancer, especially in Chinese, while the minor allele of polymorphism rs11821102 may be associated with a decreased susceptibility to cancer. Nevertheless, further studies on a larger population covering different ethnicities are warranted.

Positive association between CD44 gene rs13347 C>T polymorphism and risk of cancer in Asians: a systemic review and meta-analysis

Background

Cluster of differentiation 44 (CD44) is an important surface marker of cancer stem cells in a variety of tumors. A number of previous studies have been conducted to investigate the association between CD44 gene rs13347 C>T polymorphism and cancer risk in humans; nevertheless, the results remain controversial. We therefore performed this meta-analysis to confirm the role of this polymorphism in susceptibility to human cancer.

Materials and methods

The studies published up to December 2015 were searched in PubMed, Web of Science, and China National Knowledge Infrastructure databases. Twelve eligible case–control studies were identified, involving a total of 6,982 cases and 7,430 controls. Pooled odds ratio (OR) and corresponding 95% confidence interval (CI) were calculated using a fixed or random-effect model to estimate the strength of the association.

Results

The results of the overall analyses indicated that CD44 gene rs13347 polymorphism was significantly associated with cancer risk in Asians (CT vs CC: OR =1.35, 95% CI =1.12–1.62; TT vs CC: OR =1.99, 95% CI =1.52–2.60; TT + CT vs CC: OR =1.41, 95% CI =1.16–1.71; and TT vs CC + CT: OR =1.74, 95% CI =1.41–2.14), especially in Chinese population (CT vs CC: OR =1.42, 95% CI =1.16–1.75; TT vs CC: OR =2.13, 95% CI =1.58–2.86; TT + CT vs CC: OR =1.50, 95% CI =1.21–1.87; and TT vs CC + CT: OR =1.80, 95% CI =1.43–2.26). In stratified analyses by cancer types, there was evidence for an association between this polymorphism and nasopharyngeal cancer and breast cancer, respectively.

Conclusion

The results of this meta-analysis suggest that the CD44 gene rs13347 C>T polymorphism is associated with elevated risk of human cancer in Asians, especially in Chinese population. Further well-designed studies on a larger population covering other ethnicities should be carried out to validate our results.

Long Non-Coding RNA ucoo2kmd.1 Regulates CD44-Dependent Cell Growth by Competing for miR-211-3p in Colorectal Cancer

In addition to protein-coding genes, the human genome makes a large amount of noncoding RNAs. Long non-coding RNAs (lncRNAs) have been described as the largest subclass of the non-coding transcriptome in human noncoding RNAs. In recent years, lncRNAs have been considered to be the key regulators of tumor behavior. In this study, based on previous research, we investigated the expression and biological role of a newly identified cancer-related lncRNA, lncRNA-uc002kmd.1. We analyzed the relationship between lncRNA-uc002kmd.1 and colorectal cancer (CRC) in a total 45 CRC and paired adjacent, non-tumor tissue samples. We found that lncRNA-uc002kmd.1 expression was usually highly expressed in carcinoma compared with the tissue adjacent to the carcinoma. Through a series of experiments, the results showed that lncRNA-uc002kmd.1 regulates CD44 as a molecular decoy for miR211-3p. Our data indicated that the overexpression of lncRNA-uc002kmd.1 enhanced cell proliferation in CRC.

cir-ITCH plays an inhibitory role in colorectal cancer by regulating the Wnt/β-catenin pathway

Noncoding RNAs (ncRNAs) are the dominant product of eukaryotic transcription. These products range from short microRNAs (miRNAs) to long intergenic noncoding RNAs (lincRNAs). Circular RNAs composed of exonic sequences represent an understudied form of ncRNA that was discovered more than 20 years ago. Using a TaqMan-based reverse transcriptase polymerase chain reaction assay, we analyzed the relationship between cir-ITCH expression and colorectal cancer (CRC) in a total of 45 CRCs and paired adjacent non-tumor tissue samples. We found that cir-ITCH expression was typically down-regulated in CRC compared to the peritumoral tissue. This result, as well as several follow-up experiments, showed that cir-ITCH could increase the level of ITCH, which is involved in the inhibition of the Wnt/β-catenin pathway. Therefore, our results showed that cir-ITCH plays a role in CRC by regulating the Wnt/β-catenin pathway.

Role of integrin a5b1 in adhesion, migration and extramedullary infiltration of gastric cancer cells

AIM: To investigate the role of the adhesion molecule integrin a5b1 in adhesion, migration and extramedullary infiltration of gastric cancer cells.

METHODS: Immunohistochemistry and RT-PCR were used to measure integrin a5b1protein and mRNA expression levels in cell lines HTB-103, CRL-5822, CRL-5971 and CRL-5973. Different cell lines were randomly divided into an experimental group and a control group. The experimental group was incubated with anti-integrin a5b1 antibody, and the control group was incubated with control IgG. After incubation, the adhesion, migration and extramedullary infiltration of the above cells and ECV304 cells were assessed.

RESULTS: The relative mRNA expression levels of integrin a5b1 were significantly higher in CRL-5822, CRL-5971 and CRL-5973 cells than in HTB-103 cells (0.0821 ± 0.0128, 0.185 ± 0.0082, 0.798 ± 0.042 vs 0.0002 ± 0.0000, P < 0.05). The rates of adhesion, migration and extramedullary infiltration in CRL-5822, CRL-5971 and CRL-5973 cells in the experimental groups were significantly lower than those in the control groups (adhesion (%): 52.16 ± 2.52 vs 83.89 ± 7.21, 44.22 ± 2.59 vs 71.17 ± 7.38, 33.58 ± 4.06 vs 60.89 ± 10.59; migration (%): 45.96 ± 1.21 vs 75.41 ± 9.51, 38.86 ± 1.99 vs 65.78 ± 14.62, 24.65 ± 3.28 vs 49.91 ± 13.47; infiltration rate (%): 29.85 ± 4.63 vs 42.63 ± 7.69, 21.31 ± 3.24 vs 29.92 ± 5.47, 13.67 ± 3.48 vs 21.59 ± 6.72; P < 0.05 for all), but the above indexes did not differ in HTB-103 cells between the two groups (P > 0.05 for all).

CONCLUSION: The adhesion molecule integrin a5b1 may be involved in the adhesion, migration and extramedullary infiltration of gastric cancer cells.