Germline mutations of PALB2 gene in a sequential series of Chinese patients with breast cancer

Spectrum and characteristics of germline PALB2 pathogenic variants in 1556 early-onset breast cancer patients in China

PURPOSE

Limited data are available regarding the partner and localizer of BRCA2 (PALB2) in Chinese patients with early breast cancer. This study aimed to assess the spectrum and characteristics of germline PALB2 pathogenic variants in this population.

METHODS

Peripheral blood samples were collected from 1556 patients diagnosed with BRCA1/2-negative early-onset breast cancer. All coding regions and exon‒intron boundaries of the PALB2 genes were screened through next-generation sequencing.

RESULTS

The prevalence of PALB2 pathogenic variants was approximately 0.77% in the cohort. Eleven PALB2 pathogenic variants were identified in twelve participants, including five frameshift mutations and six nonsense mutations. All other variants were detected once, except for PALB2 c.1056_1057del (detected twice). Two PALB2 carriers (2/12, 16.7%) have documented family history of breast cancer and/or ovarian cancer. Patients with a positive family history exhibited a threefold higher possibility of being identified as PALB2 carriers than those without a family history (2% vs. 0.69%), although the difference was not statistically significant (p = 0.178). Compared to non-carriers, PALB2 carriers has a tendency to appear in younger age (≤ 30 years) (25% vs 14.4%), human epidermal growth factor receptor-2 (HER2)-negative status (83.3% vs. 70.2%), and diagnosed with invasive micropapillary carcinoma (16.7% vs 3.1%).

CONCLUSION

The prevalence of the germline PALB2 pathogenic variants was approximately 0.77% in Chinese patients with BRCA1/2-negative early-onset breast cancer. Our findings is crucial for understanding population-specific genetic risks and offering insights that can enhance genetic counseling and genetic testing strategies in this population.

Whole genome and transcriptome integrated analyses guide clinical care of pediatric poor prognosis cancers

The role for routine whole genome and transcriptome analysis (WGTA) for poor prognosis pediatric cancers remains undetermined. Here, we characterize somatic mutations, structural rearrangements, copy number variants, gene expression, immuno-profiles and germline cancer predisposition variants in children and adolescents with relapsed, refractory or poor prognosis malignancies who underwent somatic WGTA and matched germline sequencing. Seventy-nine participants with a median age at enrollment of 8.8 y (range 6 months to 21.2 y) are included. Germline pathogenic/likely pathogenic variants are identified in 12% of participants, of which 60% were not known prior. Therapeutically actionable variants are identified by targeted gene report and whole genome in 32% and 62% of participants, respectively, and increase to 96% after integrating transcriptome analyses. Thirty-two molecularly informed therapies are pursued in 28 participants with 54% achieving a clinical benefit rate; objective response or stable disease ≥6 months. Integrated WGTA identifies therapeutically actionable variants in almost all tumors and are directly translatable to clinical care of children with poor prognosis cancers.

Low expression of PALB2 is associated with poor survival in Chinese women with primary breast cancer

BACKGROUND

PALB2 plays a crucial role in genome stability and the DNA repair process, and its mutation is associated with a moderate to high risk of breast cancer. However, the status and prognostic role of PALB2 expression in breast cancer are still unclear.

MATERIALS AND METHODS

The expression level of PALB2 mRNA was evaluated by using quantitative real-time polymerase chain reaction in core biopsy samples from 563 primary breast cancer tissues.

RESULTS

In the entire cohort, low expression of PALB2 mRNA was significantly associated with poor survival (low vs. intermediate: DFS, adjusted HR = 1.79, 95% CI = 1.21-2.65, P = .003; DDFS, adjusted HR = 2.07, 95% CI = 1.34-3.20, P = .001; DSS, adjusted HR = 2.59, 95% CI = 1.45-4.64, P = .001; OS, adjusted HR = 2.77, 95% CI = 1.56-4.92, P = .001; low vs. high: DFS, adjusted HR = 1.57, 95% CI = 1.06-2.35, P = .026; DDFS, adjusted HR = 1.66, 95% CI = 1.08-2.55, P = .020; DSS, adjusted HR = 1.74, 95% CI = 1.00-3.03, P = .048; OS, adjusted HR = 1.59, 95% CI = 0.95-2.67, P = .08). Notably, among hormone receptor (HR)-positive/HER2-negative subtype, patients with low PALB2 expression also had significantly worse outcomes (low vs. intermediate: DFS, adjusted HR = 2.33, 95% CI = 1.32-4.13, P = .004; DDFS, adjusted HR = 2.78, 95% CI = 1.47-5.27, P < .001; DSS, adjusted HR = 3.08, 95% CI = 1.27-7.43, P = .013; OS, adjusted HR = 3.15, 95% CI = 1.32-7.50, P = .010; low vs. high: DFS, adjusted HR = 1.84, 95% CI = 1.04-3.28, P = .04; DDFS, adjusted HR = 1.82, 95% CI = 0.99-3.36, P = .05; DSS, adjusted HR = 2.06, 95% CI = 0.87-4.86, P = .10; OS, adjusted HR = 1.54, 95% CI = 0.71-3.33, P = .28).

CONCLUSION

Breast cancer patients with low expression of mRNA have a poor survival, suggesting that patients with PALB2 low expression may be the potential beneficiaries for PARP inhibitors therapy.

Functional assessment of missense variants of uncertain significance in the cancer susceptibility gene PALB2

Germline PALB2 pathogenic variants are associated with an increased lifetime risk for breast, pancreatic, and ovarian cancer. However, the interpretation of the pathogenicity of numerous PALB2 missense variants of uncertain significance (VUSs) identified in germline genetic testing remains a challenge. Here we selected ten potentially pathogenic PALB2 VUSs identified in 2279 Chinese patients with breast cancer and evaluated their impacts on PALB2 function by systematic functional assays. We showed that three PALB2 VUSs p.K16M [c.47 A > T], p.L24F [c.72 G > C], and p.L35F [c.103 C > T] in the coiled-coil domain impaired PALB2-mediated homologous recombination. The p.L24F and p.L35F variants partially disrupted BRCA1-PALB2 interactions, reduced RAD51 foci formation in response to DNA damage, abrogated ionizing radiation-induced G2/M checkpoint maintenance, and conferred increased sensitivity to olaparib and cisplatin. The p.K16M variant presented mild effects on BRCA1-PALB2 interactions and RAD51 foci formation. Altogether, we identify two novel PALB2 VUSs, p.L24F and p.L35F, that compromise PALB2 function and may increase cancer risk. These two variants display marked olaparib and cisplatin sensitivity and may help predict response to targeted therapy in the clinical treatment of patients with these variants.

Epigenetic study of early breast cancer (EBC) based on DNA methylation and gene integration analysis

Breast cancer (BC) is one of the leading causes of cancer-related deaths in women. The purpose of this study is to identify key molecular markers related to the diagnosis and prognosis of early breast cancer (EBC). The data of mRNA, lncRNA and DNA methylation were downloaded from The Cancer Genome Atlas (TCGA) dataset for identification of differentially expressed mRNAs (DEmRNAs), differentially expressed lncRNAs (DElncRNAs) and DNA methylation analysis. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyzes were used to identify the biological functions of DEmRNAs. The correlation analysis between DNA methylation and DEmRNAs was carried out. Then, diagnostic analysis and prognostic analysis of identified DEmRNAs and DElncRNAs were also performed in the TCGA database. Subsequently, methylation state verification for identified DEmRNAs was performed in the GSE32393 dataset. In addition, real-time polymerase chain reaction (RT-PCR) in vitro verification of genes was performed. Finally, AC093110.1 was overexpressed in human BC cell line MCF-7 to verify cell proliferation and migration. In this study, a total of 1633 DEmRNAs, 750 DElncRNAs and 8042 differentially methylated sites were obtained, respectively. In the Venn analysis, 11 keys DEmRNAs (ALDH1L1, SPTBN1, MRGPRF, CAV2, HSPB6, PITX1, WDR86, PENK, CACNA1H, ALDH1A2 and MME) were we found. ALDH1A2, ALDH1L1, HSPB6, MME, MRGPRF, PENK, PITX1, SPTBN1, WDR86 and CAV2 may be considered as potential diagnostic gene biomarkers in EBC. Strikingly, CAV2, MME, AC093110.1 and AC120498.6 were significantly actively correlated with survival. Methylation state of identified DEmRNAs in GSE32393 dataset was consistent with the result in TCGA. AC093110.1 can affect the proliferation and migration of MCF-7. ALDH1A2, ALDH1L1, HSPB6, MME, MRGPRF, PENK, PITX1, SPTBN1, WDR86 and CAV2 may be potential diagnostic gene biomarkers of EBC. Strikingly, CAV2, MME, AC093110.1 and AC120498.6 were significantly actively correlated with survival. The identification of these genes can help in the early diagnosis and treatment of EBC. In addition, AC093110.1 can regulate SPTBN1 expression and play an important role in cell proliferation and migration, which provides clues to clarify the regulatory mechanism of EBC.

Familial Breast Cancer: Disease Related Gene Mutations and Screening Strategies for Chinese Population

BACKGROUND

About 5%-10% of the breast cancer cases have a hereditary background, and this subset is referred to as familial breast cancer (FBC). In this review, we summarize the susceptibility genes and genetic syndromes associated with FBC and discuss the FBC screening and high-risk patient consulting strategies for the Chinese population.

METHODS

We searched the PubMed database for articles published between January 2000 and August 2021. Finally, 380 pieces of literature addressing the genes and genetic syndromes related to FBC were included and reviewed.

RESULTS

We identified 16 FBC-related genes and divided them into three types (high-, medium-, and low-penetrance) of genes according to their relative risk ratios. In addition, six genetic syndromes were found to be associated with FBC. We then summarized the currently available screening strategies for FBC and discussed those available for high-risk Chinese populations.

CONCLUSION

Multiple gene mutations and genetic disorders are closely related to FBC. The National Comprehensive Cancer Network (NCCN) guidelines recommend corresponding screening strategies for these genetic diseases. However, such guidelines for the Chinese population are still lacking. For screening high-risk groups in the Chinese population, genetic testing is recommended after genetic counseling.

Hereditary breast cancer and ancestry in the Madeira archipelago: an exploratory study

Access to genetic testing and counselling in remote areas such as the Madeira archipelago, in the Northern Atlantic Ocean, may be complex. Different counselling methods, including telegenetics, should be explored. In this study, we characterise the Hereditary Breast/Ovarian Cancer (HBOC) families with Madeira ancestry enrolled in our programme. Of a total of 3,566 index patients tested between January 2000 and June 2018, 68 had Madeira ancestry and 22 were diagnosed with a pathogenic germline variant (PV). As in the whole group, BRCA2 PV were more frequent in Madeira patients (68.4%: c.9382C>T (26.3%), c.658_659del (21%), c.156_157insAlu (10.5%), c.793+1G>A (5.3%) and c.298A>T (5.3%). However, the most frequently diagnosed PV in Madeira patients was the BRCA1 c.3331_3334del (31.6%). BRCA1/2 detection rates were 27.9% and 10.5% for Madeira and the whole group, respectively. This study is the first characterisation of HBOC patients with Madeira ancestry. A distinct pattern of BRCA1/2 variants was observed, and the geographic clustering of BRCA1 c.3331_3334del variant may support the possibility of a founder mutation previously described in Northern Portugal. The high detection rate observed reinforces the need to reduce gaps in access to genetic testing in Madeira and other remote areas. According to current guidelines, timely identification of HBOC patients can contribute to their ongoing care and treatment.

Identification of Seven Cell Cycle-Related Genes with Unfavorable Prognosis and Construction of their TF-miRNA-mRNA regulatory network in Breast Cancer

Breast cancer (BC), with complex tumorigenesis and progression, remains the most common malignancy in women. We aimed to explore some novel and significant genes with unfavorable prognoses and potential pathways involved in BC initiation and progression via bioinformatics methods. BC tissue-specific microarray datasets of GSE42568, GSE45827 and GSE54002, which included a total of 651 BC tissues and 44 normal breast tissues, were obtained from the Gene Expression Omnibus (GEO) database, and 124 differentially expressed genes (DEGs) were identified between BC tissues and normal breast tissues via R software and an online Venn diagram tool. Database for Annotation, Visualization and Integration Discovery (DAVID) software showed that 65 upregulated DEGs were mainly enriched in the regulation of the cell cycle, and Search Tool for the Retrieval of Interacting Genes (STRING) software identified the 39 closest associated upregulated DEGs in protein-protein interactions (PPIs), which validated the high expression of genes in BC tissues by the Gene Expression Profiling Interactive Analysis (GEPIA) tool. In addition, 36 out of 39 BC patients showed significantly worse outcomes by Kaplan-Meier plotter (KM plotter), and an additional Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis revealed that seven genes (cyclin E2 (CCNE2), cyclin B1 (CCNB1), cyclin B2 (CCNB2), mitotic checkpoint serine/threonine kinase B (BUB1B), dual-specificity protein kinase (TTK), cell division cycle 20 (CDC20), and pituitary tumor transforming gene 1 (PTTG1)) were markedly enriched in the cell cycle pathway. Analysis of the clinicopathological characteristics of hub genes revealed that seven cell cycle-related genes (CCRGs) were significantly highly expressed in four BC subtypes (luminal A, luminal B, HER2-positive and triple-negative (TNBC)), and except for the CCNE2 gene, high expression levels were significantly associated with tumor pathological grade and stage and metastatic events of BC. Furthermore, genetic mutation analysis indicated that genetic alterations of CCRGs could also significantly affect BC patients' prognosis. A quantitative real-time polymerase chain reaction (qRT-PCR) assay found that the seven CCRGs were significantly differentially expressed in BC cell lines. Integration of published multilevel expression data and a bioinformatics computational approach were used to predict and construct a regulation mechanism: a transcription factor (TF)-microRNA (miRNA)-messenger RNA (mRNA) regulation network. The present work is the first to construct a regulatory network of TF-miRNA-mRNA in BC for CCRGs and provides new insights into the molecular mechanism of BC.

Genomic Profiling Comparison of Germline BRCA and Non-BRCA Carriers Reveals CCNE1 Amplification as a Risk Factor for Non-BRCA Carriers in Patients With Triple-Negative Breast Cancer

Background: Differences in genomic profiling and immunity-associated parameters between germline BRCA and non-BRCA carriers in TNBC with high tumor burden remain unexplored. This study aimed to compare the differences and explore potential prognostic predictors and therapeutic targets. Methods: The study cohort included 21 consecutive TNBC cases with germline BRCA1/2 mutations and 54 non-BRCA carriers with a tumor size ≥ 2 cm and/or ≥1 affected lymph nodes. Differences in clinicopathological characteristics and genomic profiles were analyzed through next-generation sequencing. Univariate Kaplan-Meier analysis and Cox regression model were applied to survival analysis. Immunohistochemistry was used to confirm the consistency between CCNE1 amplification and cyclin E1 protein overexpression. Results: The cohort included 16 and five patients with germline BRCA1 and BRCA2 mutations, respectively. Patients with germline BRCA1/2 mutations were diagnosed at a significantly younger age and were more likely to have a family history of breast and/or ovarian cancer. Six non-BRCA carriers (11.11%) carried germline mutations in other cancer susceptibility genes, including five mutations in five homologous recombination repair (HRR) pathway genes (9.26%) and one mutation in MSH3 (1.85%). Somatic mutations in HRR pathway genes were found in 22.22 and 14.29% of the non-BRCA and BRCA carriers, respectively. PIK3CA missense mutation (p = 0.046) and CCNE1 amplification (p = 0.2) were found only in the non-BRCA carriers. The median tumor mutation burden (TMB) was 4.1 Muts/Mb, whereas none of the cases had high microsatellite instability (MSI). BRCA status did not affect disease-free survival (DFS, p = 0.15) or overall survival (OS, p = 0.52). CCNE1 amplification was an independent risk factor for DFS in non-BRCA carriers with TNBC (HR 13.07, 95% CI 2.47-69.24, p = 0.003). Consistency between CCNE1 amplification and cyclin E1 protein overexpression was confirmed with an AUC of 0.967 for cyclin E1 signal intensity. Conclusions: We found differences in genetic alterations between germline BRCA and non-BRCA carriers with TNBC and a high tumor burden. TMB and MSI may not be suitable predictors of TNBC for immune checkpoint inhibitors. Notably, CCNE1 amplification is a novel potential prognostic marker and therapeutic target for non-BRCA carriers with TNBC. Cyclin E1 may be used instead of CCNE1 to improve clinical applicability.

Germline PALB2 Mutations in Cancers and Its Distinction From Somatic PALB2 Mutations in Breast Cancers

PALB2 is an important BRCAx candidate for familial breast cancers (FBC). PALB2 pathogenic variants (PVs) may not to conform to "two hit" paradigm. However, a recent study demonstrates that in the majority PALB2 germline mutant breast cancers, the loss of heterozygosity (LOH) and somatic point mutations are the "second hit." This study aimed to investigate the second hits in germline PALB2 mutations in breast cancers. We screened out 28 germline PALB2-mutation carriers among 480 familial cancer patients (including 143 FBC patients) in Geneplus database pool. Of the 143 patients with FBC, 10 had mono-allelic PALB2 germline mutations. All these germline PALB2 mutations were high-risk stop-gain, frameshift, or splicing mutations that concentrated in EX5-EX9 and might led to truncated proteins, severe functional defects and malignant phenotype. The hotspots were c.1057A[3 > 2] and c.3114-1G > A. Other mutations included c.389delA, c.2068C > T, c.2167_2168delAT, c.2629delT and c.2968G > T. Only one FBC patient has PALB2 somatic mutation and two patients had LOH of PALB2. All germline PALB2 mutations were high-risk mutations, whereas the somatic PALB2 mutations were moderate-risk missense mutations. We also distinguished PALB2 "novel mutations" from "reported mutations." In conclusion, germline PALB2 mutation should be put into the context of future screening.

Spectrum of PALB2 germline mutations and characteristics of PALB2-related breast cancer: Screening of 16,501 unselected patients with breast cancer and 5890 controls by next-generation sequencing

BACKGROUND

Partner and localizer BRCA2 (PALB2) is a breast cancer predisposition gene, but the clinical relevance of PALB2 germline mutations in Chinese patients with breast cancer remains unknown. This study attempted to investigate the full prevalence and spectrum of PALB2 germline mutations in China and the associations between PALB2 germline mutations and breast cancer risk.

METHODS

A total of 21,216 unselected patients with breast cancer were enrolled from 10 provinces in China, and 5890 Chinese women without cancer were enrolled as healthy controls. PALB2 screening was based on next-generation sequencing.

RESULTS

A total of 16,501 BRCA1/2-negative patients with breast cancer were analyzed. Deleterious PALB2 mutation carriers accounted for 0.97% (n = 160) in the breast cancer cohort and for 0.19% (n = 11) in the healthy control cohort. Forty-one novel PALB2 germline mutations were identified. A high frequency of PALB2 c.751C>T was detected, and it accounted for 10.63% of the PALB2 germline mutations detected (17 of 160). PALB2 mutations were significantly associated with increased breast cancer risk (odds ratio [OR], 5.23; 95% confidence interval [CI], 2.84-9.65; P < .0001), especially among women 30 years old or younger (OR, 10.09; 95% CI, 3.95-25.79; P < .0001). Clinical characteristics, including a family history, bigger tumor size, triple-negative breast cancer, positive lymph nodes, and bilateral breast cancer, were closely related to PALB2 mutations.

CONCLUSIONS

This study revealed a comprehensive spectrum of PALB2 germline mutations and characteristics of PALB2-related breast cancer in China. PALB2 germline mutations confer a moderately increased risk for breast cancer but profoundly increase breast cancer risk for those 30 years old or younger in the Chinese population.

Comparison of BRCA versus non-BRCA germline mutations and associated somatic mutation profiles in patients with unselected breast cancer

The data on the phenotypes associated with some rare germline mutations in Chinese breast cancer patients are limited. The difference in somatic mutation profiles in breast cancer patients with germline BRCA and non-BRCA mutations remains unexplored. We interrogated the germline and somatic mutational profile of 524 Chinese breast cancer patients with various stages unselected for predisposing factors using a panel consisting of 520 cancer-related genes including 62 cancer susceptibility genes. We divided the patients into three groups according to germline mutations: Germline-BRCA1/2, Germline-others (non-BRCA) and Others (non-carriers). A total of 58 patients (11.1%) carried 76 likely pathogenic or pathogenic (LP/P) germline variants in 15 cancer predisposition genes. Germline BRCA1/2 mutations were detected from 29 (5.53%) patients; with 11 (2.10%) BRCA1 carriers and 18 (3.44%) BRCA2 carriers. In addition, LP/P germline mutations were detected in other genes including MUTYH (n=4), PALB2 (n=4), ATM (n=3), BRIP1 (n=3), CDH1 (n=3), RAD51C (n=3), CHEK2 (n=2), FANCA (n=2), PMS2 (n=2), TP53 (n=2), FANCI (n=1), FANCL (n=1) and PTEN (n=1). At least one variant of uncertain significance (VUS) was identified in 490 (93.5%) patients. Young age (P=0.011), premenopausal status (P=0.013), and breast/ovarian cancer family history (P=0.001) were correlated with germline mutations. Germline-BRCA1/2 group was detected with more missense (P=0.02) and less copy-number amplification (P=0.04) than Germline-others group. Meanwhile, Germline-others group and Others group are very similar (P>0.05). The mutation rates of AKT1, CCND1, FGFR1, and PIK3CA were different among the three groups. By investigating all breast and ovarian cancer-related genes listed in the US genetic guidelines, we identified 15 cancer susceptibility genes frequently mutated in the germline of our population and must be included in cancer predisposition screening. Our study contributed a better understanding of the tumor characteristics of patients with LP/P germline mutations.

Identification of a novel germline BRCA2 variant in a Chinese breast cancer family

Breast cancer is the most frequently diagnosed cancer and the leading cause of cancer-related deaths in women worldwide. In this study, a large Chinese pedigree with breast cancer including a proband and two female patients was recruited and a familial history of breast cancer was collected by questionnaire. Clinicopathological assessments and neoadjuvant therapy-related information were obtained for the proband. Blood samples were taken, and gDNA was extracted. The BRCA1/2 and PALB2 genes were screened using next-generation sequencing by a targeted gene panel. We have successfully identified a novel, germline heterozygous, missense mutation of the gene BRCA2: c.7007G>T, p.R2336L, which is likely to be pathogenic in the proband and her elder sister who both had breast cancer. Furthermore, the risk factors for developing breast cancer in this family are discussed. Thus, genetic counselling and long-term follow-up should be provided for this family of breast cancer patients as well as carriers carrying a germline variant of BRCA2: c.7007G>T (p.R2336L).

Bioinformatics analysis of the interactions among lncRNA, miRNA and mRNA expression, genetic mutations and epigenetic modifications in hepatocellular carcinoma

The present study aimed to investigate the regulatory networks involving long noncoding RNA (lncRNA), microRNA (miRNA), mRNA, genetic mutations and epigenetic modifications in hepatocellular carcinoma (HCC) by analyzing datasets from The Cancer Genome Atlas (TCGA) database. TCGA was mined, and miRNAs, lncRNAs and mRNAs that were differentially expressed in HCC were identified using R software. A gene regulatory network was constructed using Cytoscape software. Representative genes were selected for functional enrichment analysis using Gene Ontology and Kyoto Encyclopedia of Genes and Genomes. The associations among various proteins and protein networks were identified using the online software Search Tool for the Retrieval of Interacting Genes/Proteins. The cBioPortal database was used to analyze the association between genetic mutations and epigenetic modification, and the development of HCC. A total of 35 mRNAs were predicted to be targeted by 77 lncRNAs and 16 miRNAs, establishing a lncRNA‑miRNA‑mRNA regulatory network for HCC. Multivariable Cox regression analysis suggested that long intergenic non‑protein coding RNA 200, miRNA‑137, PDZ binding kinase and DNA polymerase θ were independent prognostic factors. In a regulatory network centered on miRNA‑424, six mRNA target genes were associated with HCC survival rates. Protein‑protein interaction analysis suggested that cell division cycle 25A (CDC25A) interacted with centrosomal protein 55 (CEP55), claspin, E2F transcription factor 7 and cyclin E1 (CCNE1. Mutations in CEP55 affected overall survival and disease‑free survival in HCC, whereas, mutations in CDC25A affected overall survival, and mutations in E2F7 affected disease‑free survival. Decreased methylation levels of CEP55, CDC25A and CCNE1 were associated with vascular invasion. The survival rate of patients with hypermethylation of CCNE1 and CEP55 was significantly associated with the rate of methylation of these loci. The present study provides an integrated bioinformatics analysis of gene expression, genetic mutations and epigenetic modifications that may be associated with the development of HCC.