Genetic and epigenetic inactivation ofLTFgene at 3p21.3 in lung cancers

Lactoferrin suppresses the progression of colon cancer under hyperglycemia by targeting WTAP/m6A/NT5DC3/HKDC1 axis

BACKGROUND

Although the relationship between type 2 diabetes (T2D) and the increased risk of colorectal carcinogenesis is widely defined in clinical studies, the therapeutic methods and molecular mechanism of T2D-induced colon cancer and how does hyperglycemia affect the progression is still unknown. Here, we studied the function of lactoferrin (LF) in suppressing the progression of colon cancer in T2D mice, and uncovered the related molecular mechanisms in DNA 5mC and RNA m6A levels.

METHODS

We examined the effects of LF (50% iron saturation) on the migration and invasion of colon tumor cells under high concentration of glucose. Then, transcriptomics and DNA methylation profilings of colon tumor cells was co-analyzed to screen out the special gene (NT5DC3), and the expression level of NT5DC3 in 75 clinical blood samples was detected by q-PCR and western blot, to investigate whether NT5DC3 was a biomarker to distinguish T2D patients and T2D-induced colon cancer patients from healthy volunteers. Futhermore, in T2D mouse with xenografted colon tumor models, the inhibitory effects of LF and NT5DC3 protein on colon tumors were investigated. In addition, epigenetic alterations were measured to examine the 5mC/m⁶A modification sites of NT5DC3 regulated by LF. Utilizing siRNA fragments of eight m⁶A-related genes, the special gene (WTAP) regulating m⁶A of NT5DC was proved, and the effect of LF on WTAP/NT5DC3/HKDC1 axis was finally evaluated.

RESULTS

A special gene NT5DC3 was screened out through co-analysis of transcriptomics and DNA methylation profiling, and HKDC1 might be a downstream sensor of NT5DC3. Mechanistically, LF-dependent cellular DNA 5mC and RNA m⁶A profiling remodeling transcriptionally regulate NT5DC3 expression. WTAP plays a key role in regulating NT5DC3 m⁶A modification and subsequently controls NT5DC3 downstream target HKDC1 expression. Moreover, co-treatment of lactoferrin and NT5DC3 protein restrains the growth of colon tumors by altering the aberrant epigenetic markers. Strikingly, clinical blood samples analysis demonstrates NT5DC3 protein expression is required to direct the distinction of T2D or T2D-induced colon cancer with healthy humans.

CONCLUSIONS

Together, this study reveals that lactoferrin acts as a major factor to repress the progression of colon cancer under hyperglycemia, thus, significantly expanding the landscape of natural dietary mediated tumor suppression.

Potential of Lactoferrin in the Treatment of Lung Diseases

Lactoferrin (LF) is a multifunctional iron-binding glycoprotein that exhibits a variety of properties, such as immunomodulatory, anti-inflammatory, antimicrobial, and anticancer, that can be used to treat numerous diseases. Lung diseases continue to be the leading cause of death and disability worldwide. Many of the therapies currently used to treat these diseases have limited efficacy or are associated with side effects. Therefore, there is a constant pursuit for new drugs and therapies, and LF is frequently considered a therapeutic agent and/or adjunct to drug-based therapies for the treatment of lung diseases. This article focuses on a review of the existing and most up-to-date literature on the contribution of the beneficial effects of LF on the treatment of lung diseases, including asthma, viral infections, cystic fibrosis, or lung cancer, among others. Although in vitro and in vivo studies indicate significant potency of LF in the treatment of the listed diseases, only in the case of respiratory tract infections do human studies seem to confirm them by demonstrating the effectiveness of LF in reducing episodes of illness and shortening the recovery period. For lung cancer, COVID-19 and sepsis, the reports are conflicting, and for other diseases, there is a paucity of human studies conclusively confirming the beneficial effects of LF.

Integrated N-glycoproteomics Analysis of Human Saliva for Lung Cancer

Aberrant protein N-glycosylation is a cancer hallmark, which has great potential for cancer detection. However, large-scale and in-depth analysis of N-glycosylation remains challenging because of its high heterogeneity, complexity, and low abundance. Human saliva is an attractive diagnostic body fluid, while few efforts explored its N-glycoproteome for lung cancer. Here, we utilized a zwitterionic-hydrophilic interaction chromatography-based strategy to specifically enrich salivary glycopeptides. Through quantitative proteomics analysis, 1492 and 1234 intact N-glycopeptides were confidently identified from pooled saliva samples of 10 subjects in the nonsmall-cell lung cancer group and 10 subjects in the normal control group. Accordingly, 575 and 404 N-glycosites were revealed for the lung cancer group and normal control group. In particular, 154 N-glycosites and 259 site-specific glycoforms were significantly dysregulated in the lung cancer group. Several N-glycosites located at the same glycoprotein and glycans attached to the same N-glycosites were observed with differential expressions, including haptoglobin, Mucin-5B, lactotransferrin, and α-1-acid glycoprotein 1. These N-glycoproteins were mainly related to inflammatory responses, infectious diseases, and cancers. Our study achieved comprehensive characterization of salivary N-glycoproteome, and dysregulated site-specific glycoforms hold promise for noninvasive detection of lung cancer.

Lactoferrin CpG Island Hypermethylation and Decoupling of mRNA and Protein Expression in the Early Stages of Prostate Carcinogenesis

Lactoferrin (LTF) is an iron-binding protein canonically known for its innate and adaptive immune functions. LTF may also act as a tumor suppressor with antiproliferative action. LTF is inactivated genetically or epigenetically in various cancers, and a CpG island spanning the transcriptional start site of LTF is hypermethylated in prostate cancer cell lines. We, therefore, hypothesized that LTF expression is silenced via CpG island hypermethylation in the early stages of prostate tumorigenesis carcinogenesis. Targeted methylation analysis was performed using a combination of methylated-DNA precipitation and methylation-sensitive restriction enzymes, and laser-capture microdissection followed by bisulfite sequencing on DNA isolated from prostate tissue samples, including both primary and metastatic disease. LTF mRNA in situ hybridization and LTF protein immunohistochemistry were also performed. We report that the LTF CpG island is frequently and densely methylated in high-grade prostatic intraepithelial neoplasia, primary prostate carcinoma, and metastases. We further report a decoupling of lactoferrin mRNA and protein expression, including in lesions where LTF mRNA has presumably been silenced via CpG island methylation. We conclude that LTF mRNA expression is silenced in prostate tumorigenesis via hypermethylation, supporting a role for LTF as a prostate cancer tumor suppressor gene. Likewise, the frequency at which the LTF CpG island is methylated across samples suggests it is an important and conserved step in prostate cancer initiation.

Lactoferrin, a Pleiotropic Protein in Health and Disease

SIGNIFICANCE

Lactoferrin (Lf) is a nonheme iron-binding glycoprotein strongly expressed in human and bovine milk and it plays many functions during infancy such as iron homeostasis and defense against microorganisms. In humans, Lf is mainly expressed in mucosal epithelial and immune cells. Growing evidence suggests multiple physiological roles for Lf after weaning.

RECENT ADVANCES

The aim of this review is to highlight the recent advances concerning multifunctional Lf activities.

CRITICAL ISSUES

First, we will provide an overview of the mechanisms related to Lf intrinsic synthesis or intestinal absorption as well as its interaction with a wide spectrum of mammalian receptors and distribution in organs and cell types. Second, we will discuss the large variety of its physiological functions such as iron homeostasis, transportation, immune regulation, oxidative stress, inflammation, and apoptosis while specifying the mechanisms of action. Third, we will focus on its recent physiopathology implication in metabolic disorders, including obesity, type 2 diabetes, and cardiovascular diseases. Additional efforts are necessary before suggesting the potential use of Lf as a diagnostic marker or as a therapeutic tool.

FUTURE DIRECTIONS

The main sources of Lf in human cardiometabolic disorders should be clarified to identify new perspectives for future research and develop new strategies using Lf in therapeutics. Antioxid. Redox Signal. 24, 813-836.

[Effects of decitabine against acute T lymphoblastic leukemia cell line Molt4]

目的

探讨去甲基化药物地西他滨对急性T淋巴细胞白血病细胞株Molt4细胞的影响及其可能的作用机制。

方法

CCK-8法检测地西他滨对细胞增殖的影响；Annexin Ⅴ/PI双重染色法检测地西他滨对细胞凋亡的影响；PI染色法检测细胞周期变化；转录组高通量测序筛选组间差异基因；亚硫酸氢盐测序法检测地西他滨作用Molt4细胞前后乳铁蛋白（LTF）基因启动子CpG岛的甲基化水平变化；实时定量RT-PCR及Western blot法分别检测LTF mRNA及蛋白的表达变化。

结果

地西他滨能有效抑制Molt4细胞的增殖，抑制率呈时间和剂量依赖性增加，并能诱导细胞凋亡，使细胞阻滞于G₀/G₁期。0.50 µmol/L地西他滨处理72 h后，Molt4细胞LTF基因启动子甲基化率较对照组降低（45.0%对72.3%），差异有统计学意义（P<0.05），mRNA和蛋白表达增加（P值均<0.05），同时还检测到caspase 3、caspase 9凋亡蛋白表达增加（P值均<0.05）。

结论

地西他滨诱导Molt4细胞凋亡，阻滞细胞周期在G₀/G₁期，抑制细胞增殖。LTF基因是地西他滨作用的重要靶点。

Proteogenomic Study beyond Chromosome 9: New Insight into Expressed Variant Proteome and Transcriptome in Human Lung Adenocarcinoma Tissues

This is a report of a human proteome project (HPP) related to chromosome 9 (Chr 9). To reveal missing proteins and undiscovered features in proteogenomes, both LC-MS/MS analysis and next-generation RNA sequencing (RNA-seq)-based identification and characterization were conducted on five pairs of lung adenocarcinoma tumors and adjacent nontumor tissues. Before our previous Chromosome-Centric Human Proteome Project (C-HPP) special issue, there were 170 remaining missing proteins on Chr 9 (neXtProt 2013.09.26 rel.); 133 remain at present (neXtProt 2015.04.28 rel.). In the proteomics study, we found two missing protein candidates that require follow-up work and one unrevealed protein across all chromosomes. RNA-seq analysis detected RNA expression for four nonsynonymous (NS) single nucleotide polymorphisms (SNPs) (in CDH17, HIST1H1T, SAPCD2, and ZNF695) and three synonymous SNPs (in CDH17, CST1, and HNF1A) in all five tumor tissues but not in any of the adjacent normal tissues. By constructing a cancer patient sample-specific protein database based on individual RNA-seq data and by searching the proteomics data from the same sample, we identified four missense mutations in four genes (LTF, HDLBP, TF, and HBD). Two of these mutations were found in tumor samples but not in paired normal tissues. In summary, our proteogenomic study of human primary lung tumor tissues detected additional and revealed novel missense mutations and synonymous SNP signatures, some of which are specific to lung cancers. Data from mass spectrometry have been deposited in the ProteomeXchange with the identifier PXD002523.

Lactotransferrin expression is downregulated and affects the mitogen-activated protein kinase pathway in gastric cancer

Gastric cancer (GC) is the second leading cause of cancer-associated mortality worldwide. In advanced and metastatic GC, conventional chemotherapy results in limited efficacy and the average survival rate is currently approximately 10 months. Dysregulated activation of numerous genes, including zinc finger, DHHC-type containing 14; caspase-associated recruitment domain-containing protein; and Ras association domain family member 10, have been implicated in GC. The tumor suppressor function of lactotransferrin (LTF) has been reported in a variety of tumors, including GC, nasopharyngeal carcinoma (NPC) and prostate cancer. However, the mechanism of the tumor suppressor function of LTF in GC remains unclear. In the present study, the expression levels of LTF in patient GC tissue samples were investigated using reverse transcription-quantitative polymerase chain reaction, and it was demonstrated that the LTF mRNA expression level in GC tissue samples was reduced by ~20-fold compared with the adjacent non-cancerous tissues (t=4.56, P<0.01). A similar trend in LTF protein expression was observed by western blot analysis. Furthermore, the present study demonstrated that the mitogen-activated protein kinase (MAPK) signaling pathway intermediates p38, c-Jun N-terminal kinase (JNK) and c-Jun were highly expressed in GC tissue samples, and indicated that LTF downregulation may be associated with the dysregulation of the MAPK signaling pathway in GC tissues. In addition, the present study indicated that LTF overexpression reduced the expression of p38, JNK2 and c-Jun in the GC cell line, SGC7901. The present study demonstrates that LTF expression is downregulated in GC tissues and that LTF may serve an important role in the dysregulation of the MAPK signaling pathway.

Re-expression of Lactotransferrin, a candidate tumor suppressor inactivated by promoter hypermethylation, impairs the malignance of oral squamous cell carcinoma cells

BACKGROUND

Lactotransferrin (LTF) has been confirmed to act as a tumor suppressor in multiple cancers; however, its roles in oral squamous cell carcinoma (OSCC), one of malignant head and neck carcinomas, has not been explored.

METHODS

Here, the expression of LTF in OSCC tissues and TCA8113 cells was detected with RT-PCR, qPCR, and IHC. And the correlation between LTF expression and OSCC metastasis was assessed. MS-PCR was performed to reveal the methylation status in promoter regions of LTF both in OSCC tissue samples and cells. The influences of 5-Aza-Cdc treatment to the methylation status and expression levels of LTF were also analyzed. At last, the functions of LTF in OSCC progression were demonstrated by MTT analysis, clone formation assay, and cell cycle analysis in TCA8113 cells with forced ectopic expression of LTF.

RESULTS

LTF showed a low or null expression pattern in OSCC tissues and cells, at least partially, due to the hypermethylated status in promoter regions for 5-Aza-Cdc, a methyltransferase inhibitor, could restore the expression of LTF in TCA8113 cells. And the expression level of LTF exhibited a negative correlation with OSCC metastasis.

CONCLUSIONS

Re-expression of LTF inhibited the growth, proliferation, as well as cell cycle progression of TCA8113 cells. In conclusion, hypermethylation contributes much to LTF inactivation in OSCC. And LTF can partially reverse the malignant phenotypes of OSCC cells and may be served as a potential target for diagnosis and therapy of OSCC in future.

Tumor suppressor genes on frequently deleted chromosome 3p in nasopharyngeal carcinoma

Nasopharyngeal carcinoma (NPC) is among the most common malignancies in southern China. Deletion of genomic DNA, which occurs during the complex pathogenesis process for NPC, represents a pivotal mechanism in the inactivation of tumor suppressor genes (TSGs). In many circumstances, loss of TSGs can be detected as diagnostic and prognostic markers in cancer. The short arm of chromosome 3 (3p) is a frequently deleted chromosomal region in NPC, with 3p21.1-21.2 and 3p25.2-26.1 being the most frequently deleted minimal regions. In recent years, our research group and others have focused on the identification and characterization of novel target TSGs at 3p, such as RASSF1A, BLU, RBMS3, and CHL1, in the development and progression of NPC. In this review, we summarize recent findings of TSGs at 3p and discuss some of these genes in detail. A better understanding of TSGs at 3p will significantly improve our understanding of NPC pathogenesis, diagnosis, and treatment.

Underlying mechanisms for LTF inactivation and its functional analysis in nasopharyngeal carcinoma cell lines

The lactoferrin (LTF) gene, located at 3p21.3, behaves like a tumor suppressor gene in diverse tumors. To elucidate the exact role of LTF in NPC, we first detected its expression level in seven NPC cell lines by semi-quantitative reverse transcription-polymerase chain reaction (RT-PCR). The results showed the mRNA level of LTF was nearly undetectable in all the seven NPC cell lines, while it could be detected in chronic nasopharyngitis tissues. Subsequently, we used methylation-specific PCR (MSP), microsatellite assay, PCR-single-strand conformation polymorphism (PCR-SSCP) and sequencing methods to examine the promoter methylation, loss of heterozygosity (LOH) and gene mutation of LTF in NPC cell lines respectively. Consequently, we found that 100% (7 of 7) of NPC cell lines were methylated in LTF promoter, only one cell line (14%, 1 of 7) had LOH and gene mutation of LTF, respectively, while LTF exhibited re-expression in all cell lines after 5-aza-dC treatment, indicating promoter methylation should be the key mechanism causing LTF downregulation in NPC cell lines. Furthermore, patched methylation assay confirmed that promoter methylation could down-regulate LTF gene expression in NPC cells. Finally, we investigated the function of LTF in NPC cell lines by gene transfection. Restoration of LTF expression in NPC cells resulted in blockage of cell cycle progression, significant inhibition of cell growth and a reduced colony-formation capacity in vitro and obviously weaker tumor formation potential in vivo. In conclusion, our data indicate LTF may participate in NPC carcinogenesis as a negative effector, that is, a tumor suppressor gene.

Signaling Transduction Network Mediated by Tumor Suppressor/Susceptibility Genes in NPC

Nasopharyngeal carcinoma (NPC) is a polygenetic disease. SPLUNC1, UBAP1, BRD7, NAG7, NOR1, NGX6 and LTF genes were found to be tumor suppressor/susceptibility genes in different stages of NPC. SPLUNC1, an early warning molecular diagnosis marker, inhibits the bacteria clone formation, and is an innated immune molecule. SPLUNC1 can negatively regulate the ERK/MAPK signaling transduction pathway to inhibit NPC cell proliferation and induce apoptosis. BRD7, a transcript regulation factor, interacts with BRD2, and promotes apoptosis induced by BRD2. Its promoter is regulated by c-Myc and SP1. BRD7 inhibits NPC cell cycle progression, preventing passage through G0/G1 by suppressing ras/MEK/ERK, Rb/E2F and Wnt signaling pathways. Abnormal activation of BRD7 is crucial to cell cycle turbulence in NPC. NGX6, a metastasis-associated protein, can negative-regulate the EGF/Ras/MAPK signaling transduction pathway, and interacts with ezrin protein to inhibit NPC cell invasion and metastasis. LTF, also a metastasis-associated protein, can negatively regulate MAPK signal transduction pathways, such as JNK2 and ERK, to inhibit NPC cell proliferation and growth. Taken together, it was found that these tumor suppressor/susceptibility genes can regulate key molecules involved in cell signal pathways such as ras/MEK/ERK, Rb/E2F and EGFR ras/MEK/MAPK, and can regulate the expression of some adhesion molecules such as ezrin, nm23 and α-catenin. According to functional genomics and signaling transduction pathways, we have described a signaling cross-talk network between the tumor suppressor/susceptibility genes involved in NPC. These tumor suppressor/susceptibility genes may be potential treatment targets for NPC in the future.

Alterations of 3p21.31 tumor suppressor genes in head and neck squamous cell carcinoma: Correlation with progression and prognosis

The aim of our study was to analyze the alterations of some candidate tumor suppressor genes (TSGs) viz. LIMD1, LTF, CDC25A, SCOTIN, RASSF1A and CACNA2D2 located in the chromosomal region 3p21.31 associated with the development of early dysplastic lesions of head and neck. In analysis of 72 dysplastic lesions and 116 squamous cell carcinoma of head and neck, both deletion and promoter methylation have been seen in these genes except for CDC25A and SCOTIN where no methylation has been detected. The alteration of LIMD1 was highest (50%) in the mild dysplastic lesions and did not change significantly during progression of tumor indicating its association with this stage of the disease. It was evident that alterations of LTF, CDC25A and CACNA2D2 were associated with development of moderate dysplastic lesions, while alterations in RASSF1A and CACNA2D2 were needed for progression. Novel somatic mutations were seen in exon 1 of LIMD1 (7%), intron 3/exon4 splice junction of LTF (2%) and exon 7 of cdc25A (10%). Quantitative RT-PCR analysis revealed mean reduced expression of the genes in the following order: LTF (67.6 +/- 16.8) > LIMD1 (53.2 +/- 20.1) > CACNA2D2 (23.7 +/- 7.1) > RASSF1A (15.1 +/- 5.6) > CDC25A (5.3 +/- 2.3) > SCOTIN (0.58 +/- 0.54). Immunohistochemical analysis of CDC25A showed its localization both in cytoplasm and nucleus in primary lesions and oral cancer cell lines. In absence of HPV infection, LTF and RASSF1A alterations jointly have adverse impact on survival of tobacco addicted patients. Thus, our data suggested that multiple candidate TSGs in the chromosomal 3p21.31 region were differentially associated with the early dysplastic lesions of head and neck.

Lactotransferrin: a candidate tumor suppressor-Deficient expression in human nasopharyngeal carcinoma and inhibition of NPC cell proliferation by modulating the mitogen-activated protein kinase pathway

Lactotransferrin (LTF) has been shown to regulate tumorogenesis. However, little is known about the role of LTF in regulating the development of human nasopharyngeal carcinoma (NPC). The aim of our study was to investigate whether LTF could regulate the development of NPC by characterizing the pattern of LTF expression in human NPC tissues using cDNA and tissue microarrays. Loss of LTF expression was observed in a significantly higher frequency of NPC tissues compared to that in nontumor nasopharyngeal epithelial tissues. While 61.25% of NPC tissues at the T1/T2 stage were positive for LTF expression, only 40.82% of NPC at the T3/T4 stage were stained by anti-LTF. Similarly, 41.58% of NPC with local lymph node metastasis displayed LTF expression, a value significantly lower than the 46.36% in primary tumors (p < 0.05). These findings suggest that LTF may negatively regulate the development and metastasis of NPC in vivo. Furthermore, overexpression of or treatment with LTF inhibited the proliferation of NPC cells and promoted cell cycle arrest at the G(0)/G(1) phase in vitro. While LTF treatment downregulated expression of cyclin D1 and phosphorylation of retinoblastoma protein (Rb), expression of p21 and p27 in 5-8F NPC cells was enhanced. Moreover, LTF treatment modulated the mitogen-activated protein kinase (MAPK) pathway, but did not affect p53 and STAT3 expression in 5-8F NPC cells. Thus LTF is likely to be a candidate tumor suppressor and downregulates the development of NPC by inhibiting NPC proliferation through induction of cell cycle arrest and modulation of the MAPK signaling pathway. Therefore, our findings provide new insights in understanding the mechanism(s) underlying the action of LTF in regulating the development of human NPC.

Why do we not all die of cancer at an early age?

Traditionally, surveillance against cancer was thought of as mainly immunological. With the exception of tumors with a clear viral involvement, such as immunoblastomas (Epstein-Barr virus, EBV), cervical, anogenital, and skin carcinomas (HPV), and Kaposi's sarcoma (HHV-8) where the immune system is confronted with virally encoded, nonself targets, tumors with no viral involvement provide poor targets. Attempts to influence them by immunological means are akin to the breaking of tolerance. Robust nonimmunological surveillance mechanisms include DNA repair-based checkpoint functions, and the triggering of growth arrest and/or apoptosis pathways by DNA damage or by illegitimate oncogene activation (intracellular surveillance). There is emerging evidence for epigenetic surveillance, reflected in the stringency of imprinting. A fourth mechanism, intercellular surveillance, or microenvironmental control, is rapidly gaining momentum. It can be mediated by contactual controls or by differentiation-inducing signals. Somatic hybridization experiments have shown that tumorigenicity is usually suppressed in somatic hybrids between normal and malignant cells, as long as a fairly complete chromosome complement is maintained. Individual normal cell-derived chromosomes may have a similar suppressive effect. For example, genetic and molecular dissection of human 3p that shows frequent deletions in many human tumors has identified multiple tumor suppressor genes, which can inhibit both in vitro growth and in vivo tumorigenicity. In addition, five genes were found with an "asymmetric activity," capable of suppressing tumorigenicity, without affecting in vitro growth. These genes, LTF, L1MD1, HYAL1, HYAL2, and VHL, are of particular interest because they may be involved in microenvironmental control.

Modeling non-random deletions in cancer

Chromosome deletions do abound in cancer and are detected in certain regions in a non-random manner. Although their relevance remains elusive, it is a general agreement that segmental losses provide the cell with selective growth advantage. Consequently these may contain genes and/or regulatory sequences that control normal growth and inhibit malignancy. We have developed a monochromosomal hybrid based experimental model for the generation and functional analysis of deletions, that is called "elimination test" (Et). Focused on human chromosome 3 - that was known to carry multiple 3p deletions - the Et was expected to restrict a 3p tumor suppressor region to a sufficiently small segment that permits the selection of a critically important candidate gene. Surprisingly, we detected three regions that were lost in all or majority of tumors: CER1 (3p21.3, Mb: 43.32-45.74), CER2 (3p22, Mb: 37.83-39.06) and FER (3p14.3-p21.2, Mb: 50.12-58.03). In contrast a 3q26-qter region (CRR) was regularly retained. CER1 - our main focus - contains multiple genes that may inhibit tumor growth, but 3 genes, RIS1, LF (LTF) and LIMD1 have already the necessary experimental support to be considered bona fide tumor suppressors. Tumor suppressor region borders display instability features including: (1) they break in evolution and in tumors, (2) they evolve horizontally, and (3) they are enriched with pseudogene insertions. The most remarkable features at the breakpoint cluster regions were segmental duplications that drive horizontal evolution and contribute to cancer associated instability.