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. 2019 Apr 23:3:12.
doi: 10.1038/s41698-019-0084-3. eCollection 2019.

Resistance to paclitaxel is associated with a variant of the gene BCL2 in multiple tumor types (VSports)

Rotem Ben-Hamo  1   2   3 , Alona Zilberberg  1 , Helit Cohen  1 , Keren Bahar-Shany  4 , Chaim Wachtel  1 , Jacob Korach  5 , Sarit Aviel-Ronen  6   7 , Iris Barshack  6   8 , Danny Barash  9 , Keren Levanon  4   8   10 , Sol Efroni  1
Affiliations

Resistance to paclitaxel is associated with a variant of the gene BCL2 in multiple tumor types

Rotem Ben-Hamo et al. NPJ Precis Oncol. .

Abstract (V体育2025版)

Paclitaxel, the most commonly used form of chemotherapy, is utilized in curative protocols in different types of cancer. The response to treatment differs among patients. Biological interpretation of a mechanism to explain this personalized response is still unavailable. Since paclitaxel is known to target BCL2 and TUBB1, we used pan-cancer genomic data from hundreds of patients to show that a single-nucleotide variant in the BCL2 sequence can predict a patient's response to paclitaxel. Here, we show a connection between this BCL2 genomic variant, its transcript structure, and protein abundance. We demonstrate these findings in silico, in vitro, in formalin-fixed paraffin-embedded (FFPE) tissue, and in patient lymphocytes. We show that tumors with the specific variant are more resistant to paclitaxel. We also show that tumor and normal cells with the variant express higher levels of BCL2 protein, a phenomenon that we validated in an independent cohort of patients. Our results indicate BCL2 sequence variations as determinants of chemotherapy resistance. The knowledge of individual BCL2 genomic sequences prior to the choice of chemotherapy may improve patient survival VSports手机版. The current work also demonstrates the benefit of community-wide, integrative omics data sources combined with in-lab experimentation and validation sets. .

Keywords: Cancer genomics; High-throughput screening; Molecular biology V体育安卓版. .

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Conflict of interest statement

The authors declare no competing interests.

Figures

Fig. 1
Fig. 1
Eleven SNPs were identified within TUBB1 and BCL2. a In OV, two SNPs (rs6070697, rs1801018) present a frequency that may be of use for the stratification of patients according to their response status. b rs6070697 is of the same frequency in both groups (t test p-value < 0.96). A study of the polymorphisms of TUBB1 and BCL2 in UCEC shows similar results (c) for all polymorphism, while a more careful study (d) of rs6070697 again demonstrates that it does not present a significant difference in the two response groups (t test p-value < 0.19), and a study of HNSC follows these (t test p-value < 0.25) findings (e, f), as does a validation set composed of data from all TCGA patients that were treated with a first line of paclitaxel (excluding OV, UCEC, and HSNC) of other types of cancer. This validation set includes sequence data from 86 patients with BLCA, CESC, ESCA, LUAD, LUSC, SKCM, STAD, UCS. Similar to OV, UCEC and HNSC, this combined set does not present any polymorphism with significant association to response (g), including the candidate rs6070697 (t test p-value < 0.13) (h)
Fig. 2
Fig. 2
a OV, 144 patients have responded well to the first-line treatment, while 226 patients required additional lines of diverse chemotherapies (b). rs1801018 status is highly correlated with the affiliation to the first-line group versus the multiple-line group (chi-square p-value < 10−16). c rs1801018 in UCEC (chi-square p-value < 3 × 10−4). Panel d shows the stratification of the variant is consistent in HNSC (p-value < 0.05), as well as in the pan-cancer validation (chi-square p-value < 6 × 10−4) set (e). P-values were calculated using chi-square test. f Kaplan–Meier survival curve of ovarian cancer patients harboring rs1801018 SNO and wild-type BCL2
Fig. 3
Fig. 3
The T > C rs1801018 variant leads to significant structural changes in the mRNA secondary structure, which in turn leads to a more stable transcript and to higher BCL2 protein levels. a Predicted secondary structure of BCL2 mRNA. The secondary structure of reference, variant (+21 T > C) or random (+23 C > T) BCL2. The location of the SNP is indicated by an arrow. The analysis was conducted by MFOLD. b Base-pair probabilities corresponding to changes in local regions (RNAsnp). A significant change is evident (RNAsnp p-value = 0.0178) in the change from reference (green) to the variant (+21 T > C) (red) BCL2 version. No significant changes (RNAsnp p-value = 0.7337) were identified for the random variation
Fig. 4
Fig. 4
a BCL2 mRNA transcript stability determined by specific single-nucleotide variants changes. Relative transcript levels of GFP-BCL2 variants were measured by real-time qPCR (normalized to β-actin). b rs1801018 derived BCL2 produces a significantly more stable version of transcript, with an effect lasting 4 to 6 h post induction. c Protein levels of the variant BCL2 are higher than reference and random BCL2. All blots derive from the same experiment and were processed in parallel. d GFP protein levels were quantified compared with actin using ImageJ. e BCL2 RNAseq levels from 1417 patients with seven different types of cancer from, y-axis represents averaged FPKM levels, and the x-axis represents the SNP genotype. P-values were calculated using two-sided t test
Fig. 5
Fig. 5
BCL2 genotype correlates with BCL2 positivity in primary tissue from ovarian cancer patients. Representative images of high-grade serous carcinoma stained with BCL2 (a) and their matched H&E stains (b) and their corresponding Sanger sequencing traces (c). FFPE specimens of high-grade serous ovarian tumors from 46 patients were stained with BCL2 and validated (d) for their BCL2 genotype. e Lymphocytes were extracted from 12 patients (seven patients with a reference sequence and five patients with rs1801018). BCL2 mRNA levels were quantified using qRT-PCR and normalized using endogenous levels of B-actin. f Elevated resistance to paclitaxel in the rs1801018 variant (p-value < 0.05). While the control strain, expressing the lowest amounts of BCL2, is much more sensitive than all other produced strains, both the reference and the random strains show similar sensitivities, and are significantly more sensitive than the rs1801018 strain. g BCL2 gradient assay measures cell sensitivity to paclitaxel in the presence of increasing BCL2 transfection concentrations, y-axis quantifies the ratio between the actual number of BCL2-GFP cDNA transcripts WT or SNP variant, relative to their corresponding cDNA counting under no treatment (“control”). h Relative reference and variant BCL2-GFP transcript concentrations measured by droplet digital PCR. i HEK293T cells, grown on coverslips and transfected with reference BCL2-GFP, rs1801018 BCL2-GFP (+ 21 T- > C) or GFP-empty vector. Localization variances between the two BCL2 versions were not observed, protein location is not a factor in the effect of rs1801018. P-values were calculated using two-sided t test
Fig. 6
Fig. 6
BCL2 variant predict response to paclitaxel in 39 ovarian cancer cell lines. a Histogram showing the response of 39 different ovarian cancer cell lines to paclitaxel with their BCL2 variant status (cell lines with wild-type BCL2 marked in gray, heterozygous BCL2 marked in light blue and homozygous for the variant marked in dark blue). Cell lines with low AUC (sensitive to paclitaxel) are enriched with wild-type BCL2, while cells with high AUC (resistant) are enriched with the variant form. b–d This phenomenon is to observed in other cytotoxic treatment such as vincristine, topotecan, and doxorubicin. e This was tested across 406 different treatments, and the only response paclitaxel was the only significant association with the presence of the variant
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References

    1. Links M, Brown R. Clinical relevance of the molecular mechanisms of resistance to anti-cancer drugs. Expert Rev. Mol. Med. 1999;1999:1–21. - PubMed
    1. Siegel R, Naishadham D, Jemal A. Cancer statistics, 2012. CA Cancer J. Clin. 2012;62:10–29. doi: 10.3322/caac.20138. - DOI - PubMed
    1. Ahluwalia A, et al. DNA methylation and ovarian cancer. I. Analysis of CpG island hypermethylation in human ovarian cancer using differential methylation hybridization. Gynecol. Oncol. 2001;82:261–268. doi: 10.1006/gyno.2001.6291. - DOI - PubMed
    1. Sauna ZE, Kimchi-Sarfaty C. Understanding the contribution of synonymous mutations to human disease. Nat. Rev. Genet. 2011;12:683–691. doi: 10.1038/nrg3051. - DOI - PubMed
    1. Plotkin JB, Kudla G. Synonymous but not the same: the causes and consequences of codon bias. Nat. Rev. Genet. 2011;12:32–42. doi: 10.1038/nrg2899. - DOI - PMC - PubMed