ADIPOQ gene polymorphisms and cancer risk: A meta-analysis

Exosomes from tamoxifen-resistant breast cancer cells transmit drug resistance partly by delivering miR-9-5p

Background

Resistance to drug therapy is a major impediment for successful treatment of patients suffering from breast cancer (BC). Tamoxifen (TAM) is an extensively used therapeutic agent, which substantially reduces the risk of recurrence and associated mortality in BC. This study demonstrated that exosomal transfer of microRNA-9-5p (miR-9-5p) enhanced the resistance of MCF-7 cells to TAM.

Methods

Initially, BC-related differentially expressed genes (DEGs) and their upstream regulatory miRNAs were identified. The TAM-resistant MCF-7 (MCF-7/TAM) cell line and the non-medicated sensitive MCF-7 cell line were formulated, followed by isolation of the exosomes. Next, the apoptosis rate of exosome-treated MCF-7 cells was determined after co-culture with TAM. The interaction between miR-9-5p and ADIPOQ was identified by a combination of bioinformatic analysis and luciferase activity assay. In order to validate the effect of miR-9-5p and ADIPOQ on TAM resistance in the MCF-7 cells in vitro and in vivo, miR-9-5p was delivered into the exosomes. ADIPOQ and miR-9-5p were identified as the BC-related DEG and upstream regulatory miRNA.

Results

Exosomes derived from the MCF-7/TAM cells could increase the resistance of MCF-7 cells to TAM. Notably, miR-9-5p altered the sensitivity of BC cells to TAM. In addition, ADIPOQ was negatively regulated by miR-9-5p. Furthermore, MCF-7/TAM cell-derived miR-9-5p inhibited the apoptosis of MCF-7 cells, and promoted the cell resistance to TAM. In vivo experiments in nude mice ascertained that the tumor injected with exosomal miR-9-5p showed improved resistance to TAM.

Conclusions

Exosomal transfer of miR-9-5p augmented the drug resistance of BC cells to TAM by down-regulating ADIPOQ, suggesting its functionality as a candidate molecular target for the management of BC.

A global transcriptomic pipeline decoding core network of genes involved in stages leading to acquisition of drug-resistance to cisplatin in osteosarcoma cells

MOTIVATION

Traditional cancer therapy is focused on eradicating fast proliferating population of tumor cells. However, existing evidences suggest survival of sub-population of cancer cells that can resist chemotherapy by entering a 'persister' state of minimal growth. These cells eventually survive to produce cells resistant to drugs. The identifying of appropriate targets that can eliminate the drug-tolerant 'persisters' remains a challenge. Hence, a deeper understanding of the distinctive genetic signatures that lead to resistance is of utmost importance to design an appropriate therapy.

RESULTS

In this study, deep-sequencing of mRNA was performed in osteosarcoma (OS) cells, exposed to the widely used drug, cisplatin which is an integral part of current treatment regime for OS. Transcriptomic analysis was performed in (i) untreated OS; (ii) persister sub-population of cells post-drug shock; (iii) cells which evade growth bottleneck and (iv) drug-resistant cells obtained after several rounds of drug shock and revival. The transcriptomic signatures and pathways regulated in each group were compared; the transcriptomic pipeline to the acquisition of resistance was analyzed and the core network of genes altered during the process was delineated. Additionally, our transcriptomic data were compared with OS patient data obtained from Gene Ontology Omnibus. We observed a sub-set of genes to be commonly expressed in both data sets with a high correlation (0.81) in expression pattern. To the best of our knowledge, this study is uniquely designed to understand the series of genetic changes leading to the emergence of drug-resistant cells, and implications from this study have a potential therapeutic impact.

AVAILABILITY AND IMPLEMENTATION

All raw data can be accessed from GEO database (https://www.ncbi.nlm.nih.gov/geo/) under the GEO accession number GSE86053.

SUPPLEMENTARY INFORMATION

Supplementary data are available at Bioinformatics online.

The Role of Circulating Adiponectin and SNP276G>T at ADIPOQ Gene in BRCA-mutant Women

BACKGROUND

Environmental factors may influence the lifetime risk of cancer (penetrance) in women with a BRCA mutation.

MATERIALS AND METHODS

In 89 BRCA-mutant women, affected or unaffected by breast/ovarian cancer, we explored serum levels of adipokines and their relation with the polymorphism SNP276G>T as modulators of BRCA penetrance.

RESULTS

Affected women had significantly lower adiponectin than healthy women. Affected women with rs1501299 TT had significantly lower adiponectin and higher leptin than GT and GG genotypes. GT genotype was significantly associated with the disease status [odds ratio (OR)=3.24, 95% confidence interval (95% CI)=1.03-10.17]. Women in the lower tertile of serum adiponectin had a RR of BRCA-associated cancer of 2.80, 95% CI=1.1-7.1 (p for trend=0.03) compared with women in the higher tertile.

CONCLUSION

In the SNP rs1501299 the T allele was significantly associated with lower serum levels of adiponectin in affected women, suggesting that the T allele might be related to cancer.

Transcriptomic analysis associated with reversal of cisplatin sensitivity in drug resistant osteosarcoma cells after a drug holiday

Background

Resistance to chemotherapy is one of the major hurdles in current cancer therapy. With the increasing occurrence of drug resistance, a paradigm shift in treatment strategy is required. Recently “medication vacation” has emerged as a unique, yet uncomplicated strategy in which withdrawal of drug pressure for certain duration allowed tumor cells to regain sensitivity to the drug. However, little is known about the molecular alterations associated with such an outcome.

Methods

In this study, human osteosarcoma (OS) cells resistant to the extensively used drug cisplatin, were withdrawn from drug pressure, and thereafter cytotoxic response of the cells to the drug was evaluated. We further performed next-generation RNA sequencing and compared transcriptome between parental (OS), resistant (OS-R) and the drug withdrawn (OS-DW) cells. Differentially expressed transcripts were identified, and biological association network (BAN), gene ontology (GO) and pathway enrichment analysis of the differentially regulated transcripts were performed to identify key events associated with withdrawal of drug pressure.

Results

Following drug withdrawal, the sensitivity of the cells to the drug was found to be regained. Analysis of the expression profile showed that key genes like, IRAK3, IL6ST, RELA, AKT1, FKBP1A and ADIPOQ went significantly down in OS-DW cells when compared to OS-R. Also, genes involved in Wnt signaling, PI3K-Akt, Notch signaling, and ABC transporters were drastically down-regulated in OS-DW cells compared to OS-R. Although, a very small subset of genes maintained similar expression pattern between OS, OS-R and OS-DW, nonetheless majority of the transcriptomic pattern of OS-DW was distinctively different and unique in comparison to either the drug sensitive OS or drug resistant OS-R cells.

Conclusion

Our data suggests that though drug withdrawal causes reversal of sensitivity, the transcriptomic pattern does not necessarily show significant match with resistant or parental control cells. We strongly believe that exploration of the molecular basis of drug holiday might facilitate additional potential alternative treatment options for aggressive and resistant cancers.

Haplotypes of the Ovine Adiponectin Gene and Their Association with Growth and Carcass Traits in New Zealand Romney Lambs

Adiponectin plays an important role in energy homeostasis and metabolism in mammalian adipose tissue. In this study, the relationship between adiponectin gene (ADIPOQ) haplotypes and variation in growth and carcass traits in New Zealand (NZ) Romney lambs was investigated using General Linear Models (GLMs). Eight haplotypes were found in these lambs and they were composed of the four previously reported promoter fragment sequences (A₁-D₁) and three previously reported intron 2-exon 3 sequences (A₃-C₃). The frequencies of the haplotypes ranged from 0.07% to 45.91%. The presence of A₁-A₃ was associated with a decreased pre-weaning growth rate (p = 0.037), and decreased leg lean-meat yield (p = 0.001), loin lean-meat yield (p = 0.018) and total lean-meat yield (p = 0.004). The presence of A₁-C₃ was associated with increased carcass fat depth over the 12th rib (V-GR; p = 0.001) and a decreased proportion of loin lean-meat yield (p = 0.045). The presence of B₁-A₃ was associated with an increased proportion of leg lean-meat yield (p = 0.016) and proportion of shoulder lean-meat yield (p = 0.030). No associations were found with birth weight, tailing weight and weaning weight. These results suggest that ovine ADIPOQ may have value as a genetic marker for NZ Romney sheep breeding.

ADIPOQ rs266729 G/C gene polymorphism and plasmatic adipocytokines connect metabolic syndrome to colorectal cancer

Background: ADIPOQ gene, which encode for Adiponectin (APN), is sited on chromosome 3q27 and linked to a susceptibility locus for metabolic syndrome (MetS). The ADIPOQ rs266729 G/C gene polymorphism is significantly associated with low APN levels and linked to susceptibility to develop cancer. In addition, decreased APN serum levels are linked with tumor development and progression and inversely associated with markers of inflammation. Here, we investigate the influence of APN rs266729 G/C polymorphism on adipocytokine circulating levels and their association with MetS in colorectal cancer patients (CRC). Methods: Blood samples from 105 CRC patients (50 women and 55 men) with and without MetS were genotyped for APN rs266729 G/C polymorphism by TETRA ARMS PCR. ELISA assay was used to measure plasma levels of APN and inflammatory TNF-α cytokine. Biochemical and anthropometric parameters of MetS were also analyzed. Results: We found that CRC patients (N=75) with genotype rs266729G/C or carriers of G allele were associated with a significantly increased risk of MetS development (OR =2.9) compared to those with CC genotype (N=30). Also, CG/GG genotypes were associated with significantly lower plasma APN levels and higher TNF-α levels in comparison to CC genotype (P=0.034) and APN levels were decreased in relation to BMI increases (P=0.001). Conclusions: Our findings show that APN rs266729 G/C polymorphism is associated with lower APN levels in CRC patients, indicating that decreased circulating levels of APN may be a determinant risk factor for CRC in MetS patients.

LEP rs7799039, LEPR rs1137101, and ADIPOQ rs2241766 and 1501299 Polymorphisms Are Associated With Obesity and Chemotherapy Response in Mexican Women With Breast Cancer

BACKGROUND

Obesity plays a major role in the pathogenesis of breast cancer. Leptin (LEP) and adiponectin (ADIPOQ) are important in the regulation of adipose tissue. The response to cancer treatment depends on the histological and molecular tumor type, clinical stage, and genetic variability that might promote carcinogenic development. The aim of this study was to investigate the association between overweight/obesity and polymorphisms in the LEP (rs7799039), LEP receptor (LEPR; rs1137101), and ADIPOQ genes (rs2241766, rs1501299) with the response to breast cancer treatment in Mexican women.

PATIENTS AND METHODS

A sample of 177 patients with primary breast cancer (stage I-III) and who received neoadjuvant therapy were included. Polymorphisms were genotyped and their serum LEP concentrations (n = 59) were quantified.

RESULTS

The patients' median age was 53.1 years, the frequency of overweight and obesity was 57 and 84 patients, respectively, 117 were postmenopausal, and 64 of the patients did not respond to chemotherapy. An association of the LEP rs7799039, LEPR rs1137101, and ADIPOQ rs1501299 polymorphisms with overweight/obesity was found. The patients who did not respond to treatment were more frequently obese, at clinical stage III, had metastases, and high levels of glucose. Moreover, in samples that were positive for estrogen receptor, higher levels of LEP were found, and in wild type genotypes for LEP rs7799039 and LEPR rs1137101.

CONCLUSION

There was a direct association between the polymorphisms in LEP rs7799039 and ADIPOQ rs1501299 with overweight/obesity, and these genotypes affected the response to chemotherapeutic treatment, suggesting that an obesogenic microenvironment is more favorable for tumoral progression.

Haplotypes and Sequence Variation in the Ovine Adiponectin Gene (ADIPOQ)

The adiponectin gene (ADIPOQ) plays an important role in energy homeostasis. In this study five separate regions (regions 1 to 5) of ovine ADIPOQ were analysed using PCR-SSCP. Four different PCR-SSCP patterns (A₁-D₁, A₂-D₂) were detected in region-1 and region-2, respectively, with seven and six SNPs being revealed. In region-3, three different patterns (A₃-C₃) and three SNPs were observed. Two patterns (A₄-B₄, A₅-B₅) and two and one SNPs were observed in region-4 and region-5, respectively. In total, nineteen SNPs were detected, with five of them in the coding region and two (c.46T/C and c.515G/A) putatively resulting in amino acid changes (p.Tyr16His and p.Lys172Arg). In region-1, -2 and -3 of 316 sheep from eight New Zealand breeds, variants A₁, A₂ and A₃ were the most common, although variant frequencies differed in the eight breeds. Across region-1 and region-3, nine haplotypes were identified and haplotypes A₁-A₃, A₁-C₃, B₁-A₃ and B₁-C₃ were most common. These results indicate that the ADIPOQ gene is polymorphic and suggest that further analysis is required to see if the variation in the gene is associated with animal production traits.

Adiponectin receptor 1 (ADIPOR1) rs1342387 polymorphism and risk of cancer: a meta-analysis

Many studies have indicated possible associations between a polymorphism of adiponectin receptor 1 (ADIPOR1) rs1342387 and risk of cancer, but contradictory results have been reported. The main aim of this study was to draw a reliable conclusion about the relationship between the rs1342387 polymorphism and cancer incidence, by conducting a literature search of Pubmed, Embase, Wanfang and Cochrane libraries. Eleven studies including 3, 738 cases and 4, 748 controls were identified in this meta-analysis. The ADIPOR1 rs1342387 polymorphism was associated with risk of colorectal cancer for all genetic comparison models (GG vs AA, OR: 1.44, 95%CI: 1.21 -1.70; G carriers vs A carriers, OR: 1.23, 95%CI: 1.11 -1.36; dominant model, OR: 1.28, 95%CI: 1.10 -1.49 and recessive model, OR: 1.31, 95%CI: 1.12 -1.55). Stratified by ethnicity, the rs1342387 polymorphism was significantly associated with risk of colorectal cancer in Asian ancestry for all genetic comparison models (GG vs AA, OR: 1.56, 95%CI: 1.26-1.92; G carriers vs. A carriers OR: 1.30, 95%CI: 1.18 -1.43; dominant model OR: 1.31, 95%CI: 1.08 -1.60 and recessive model OR: 1.44, 95%CI: 1.26 -1.64), but not in Caucasian or mixed (Caucasian mainly) groups. In summary, the ADIPOR1 rs1342387 polymorphism is significantly associated with risk of colorectal cancer among individuals of Asian ancestry.

The association of adiponectin gene promoter variations with non-small cell lung cancer in a Han Chinese population

Recently, in vitro studies have demonstrated that adiponectin has antiangiogenic and tumor growth-limiting properties. Additionally, serum adiponectin levels have been associated with the risk of several cancers; specifically, serum adiponectin was significantly lower in lung cancer patients with advanced-stage disease. In this study, we examined the association of adiponectin gene promoter variations associated with adiponectin gene expression and plasma levels in non-small cell lung cancer (NSCLC) in a Han Chinese population. A total of 319 patients with NSCLC and 489 healthy individuals were recruited to evaluate the association of four adiponectin gene promoter single-nucleotide polymorphisms (SNPs) (SNP-12140G>A, SNP-11426A>G, SNP-11391G>A and SNP-11377C>G) with NSCLS risk. Additionally, we constructed haplotypes of these four SNPs and evaluated the association of these haplotypes with NSCLS risk. Our results showed that among these four SNPs, only SNP-12140G>A was associated with NSCLC risk (P<0.05). The haplotype analysis showed that no haplotype was associated with NSCLC after performing a Bonferroni correction (P>0.05). Additionally, an association analysis of the four SNPs stratified into pathologic stages I+II and III+IV showed that these SNPs did not exhibit significant differences between pathologic stages I+II and III+IV. Moreover, we did not observe any differences in allele and genotype frequency for these SNPs between adenocarcinoma and squamous cell carcinoma. Our results indicated that the G allele of SNP-12140 may be a risk factor for NSCLC (OR = 1.516; 95% CI: 1.098-2.094) in this Han Chinese population.

Differential gene expression of the key signalling pathway in para-carcinoma, carcinoma and relapse human pancreatic cancer

Pancreatic cancer (PC) has a high rate of mortality and a poorly understood mechanism of progression. Investigation of the molecular mechanism of PC and exploration of the specific markers for early diagnosis and specific targets of therapy are key points to prevent and treat PC effectively and to improve their prognosis. In our study, expression profiles experiment of para-carcinoma, carcinoma and relapse human PC was performed using Agilent human whole genomic oligonucleotide microarrays with 45 000 probes. Differentially expressed genes related with PC were screened and analysed further by Gene Ontology term analysis and Kyoto encyclopaedia of genes and genomes pathway analysis. Our results showed that there were 3853 differentially expressed genes associated with pancreatic carcinogenesis and relapse. In addition, our study found that PC was related to the Jak-STAT signalling pathway, PPAR signalling pathway and Calcium signalling pathway, indicating their potential roles in pancreatic carcinogenesis and progress.

The adiponectin gene single-nucleotide polymorphism rs1501299 is associated with hepatocellular carcinoma risk

PURPOSE

Increasing lines of evidence have suggested that adiponectin, an adipocyte-derived hormone, plays an important role in the development of hepatocellular carcinoma (HCC). However, the relationship between genetic variants of the adiponectin gene (ADIPOQ) and HCC has not been previously explored. Therefore, we performed a case-control study to examine the association of haplotype-tagging single-nucleotide polymorphisms (SNPs) in ADIPOQ with HCC risk.

METHODS

Five haplotype-tagging SNPs of ADIPOQ (rs266729, rs822395, rs822396, rs2241766 and rs1501299) were genotyped in 200 HCC patients and 200 non-HCC controls by PCR amplification and direct sequencing. Logistic regression was used to estimate the risk of HCC associated with each individual SNP and we adjusted for multiple testing by the Bonferroni correction.

RESULTS

Of the five tested SNPs, rs1501299 showed a strong and significant association with HCC risk even after the Bonferroni correction. After adjusting for the serological status of the hepatitis virus B core antibody and for other SNPs, the odds ratios were 4.33 [95 % confidence interval (CI) 2.07-9.05; corrected P < 0.005] and 3.71 (95 % CI 1.84-7.48; corrected P < 0.005) for the GG genotype and GG/GT combined genotype, respectively, versus the TT genotype.

CONCLUSIONS

This is the first report, demonstrating an association of ADIPOQ polymorphisms with HCC risk. Our results implicate the ADIPOQ SNP rs1501299 as a susceptibility locus for HCC.