Immunohistochemical Determination of p53 Protein Overexpression for Predicting p53 Gene Mutations in Hepatocellular Carcinoma: A Meta-Analysis

Complex phenotypic heterogeneity of combined hepatocellular-cholangiocarcinoma with a homogenous TERT promoter mutation

To clarify the mechanism underlying the development and poor prognosis of combined hepatocellular-cholangiocarcinoma (cHCC-CCA), we characterized liver cancer driver mutations and poor prognostic markers in both the HCC and intrahepatic CCA (iCCA) components of a cHCC-CCA tumor. The telomerase reverse transcriptase (TERT) promoter mutation C228T was quantified by digital polymerase chain reaction using DNA from multiple microdissected cancer components of a single cHCC-CCA nodule. The protein expression of cancer-related markers, including TERT, was examined by serial thin-section immunohistochemistry and double-staining immunofluorescence. TERT promoter mutation and TERT protein expression were detected in all cancer components but not in noncancer regions. TERT promoter mutation frequencies were similar among components; those of TERT protein-positive cancer cells were higher in iCCA and mixed components than in HCC. The frequencies of Ki67- and p53-positive cells were similarly higher in iCCA and mixed components than in HCC. However, double-positive cells for the three proteins were unexpectedly rare; single-positive cells dominated, indicating phenotypic microheterogeneity in cancer cells within a component. Interestingly, HCC and CCA marker protein immunohistochemistry suggested dedifferentiation of HCC and transdifferentiation from HCC to iCCA in HCC and iCCA components, respectively. Such phenotypic intercomponent heterogeneity and intracomponent microheterogeneity were detected in a tumor nodule of cHCC-CCA uniformly carrying the early HCC driver mutation. Moreover, poor prognostic markers were randomly expressed without a regular pattern, consistent with the poor prognosis.

Effect of Vitamin D Supplements on Relapse or Death in a p53-Immunoreactive Subgroup With Digestive Tract Cancer: Post Hoc Analysis of the AMATERASU Randomized Clinical Trial

Importance

Recent meta-analyses of randomized clinical trials found that daily vitamin D3 supplementation had beneficial effects on cancer mortality, although the results are still controversial.

Objective

To examine whether vitamin D supplementation reduces the risk of relapse or death in a supgroup of patients with digestive tract cancer who were p53 immunoreactive.

Design, Setting, and Participants

This was a post hoc subgroup analysis of the AMATERASU randomized, double-blind, placebo-controlled clinical trial. This trial included patients at a single university hospital in Japan with digestive tract cancers between January 2010 and February 2018 followed up for a median (IQR) of 3.5 (2.5-5.3) years to compare the effects of vitamin D supplementation with placebo and was reported in 2019. Patients from among 417 participants in the AMATERASU trial whose residual serum samples were available were included. Data were analyzed from October 20 to November 24, 2022.

Interventions

Vitamin D3 (2000 IU/d) supplementation or placebo.

Main Outcomes and Measures

The primary outcome was 5-year relapse or death. The subgroup of patients who were p53 immunoreactive was defined by positivity for anti-p53 antibodies in serum and nuclear accumulation of p53 oncosuppressor protein in more than 99% of cancer cells, which is considered a biomarker for p53 missense mutations. Anti-p53 antibody levels were measured using chemiluminescent enzyme immune assay. Immunohistochemical staining data of p53 protein in cancer tissue in pathologic specimens were obtained from a previous study and divided into 4 grades.

Results

Among 392 patients with digestive tract cancer (mean [SD] age, 66 [10.7] years; 260 males [66.3%]), there were 37 patients with esophageal cancer (9.4%), 170 patients with gastric cancer (43.4%), 2 patients with small bowel cancer (0.5%), and 183 patients with colorectal cancer (46.7%). Serum anti-p53 antibody was detectable in 142 patients (36.2%), and p53-immunohistochemistry grade showed a positive association with serum anti-p53 antibody levels (coefficient = 0.19; P < .001). In the p53-immunoreactive subgroup (80 patients), relapse or death occurred in 9 of 54 patients (16.7%) in the vitamin D group and 14 of 26 patients (53.8%) in the placebo group; 5-year relapse-free survival (RFS) was significantly higher in the vitamin D group (13 patients [80.9%]) than the placebo group (1 patient [30.6%]; hazard ratio [HR], 0.27; 95% CI, 0.11-0.61; P = .002). This was significantly different from 272 patients in the non-p53 immunoreactive subgroup, in which vitamin D had no effect on 5-year RFS (vitamin D: 35 of 158 patients [22.2%] vs placebo: 24 of 114 patients [21.1%]; HR, 1.09; 95% CI, 0.65-1.84) (P for interaction = .005).

Conclusions and Relevance

This study found that vitamin D supplementation reduced the risk of relapse or death in the subgroup of patients with digestive tract cancer who were p53 immunoreactive.

Trial Registration

Identifier: UMIN000001977.

p53 expression is associated with tumor stage, grade and subtype in patients with hepatocellular carcinoma

The present study aimed to determine the expression levels of p53 in patients with hepatocellular carcinoma (HCC) and to evaluate its association with several HCC-related prognostic factors and in particular, with tumor stage, grade and subtype. Therefore, a cross-sectional study, involving 41 patients with HCC, who underwent surgical resection between January, 2013 and December, 2020 was conducted. To assess the expression levels of p53 in all patients with HCC, immunohistochemical staining was performed. In addition, the association between p53 expression and the clinicopathological characteristics of patients with HCC, including prognostic factors, was evaluated by applying the appropriate statistical analysis methods. The results revealed that among the 41 patients enrolled, 35 patients (85.4%) were positive for p53 expression. A higher percentage of positive p53 expression was observed in male patients >60 years old, with single HCC nodules >5 cm in diameter and vascular invasion, compared with their counterparts. A positive p53 expression was associated with well- and poorly differentiated HCC, but not with tumor stage and subtype. No differences in p53 expression were observed across different tumor stages and subtypes. Additionally, patients with moderately and poorly differentiated HCC exhibited significantly higher p53 expression levels compared with those suffering from well-differentiated HCC. Overall, the results demonstrated that the rate of p53 immuno-positive cells was increased in patients with HCC. In addition, p53 expression was associated with well- and poorly differentiated HCC, thus suggesting its association with a poorer prognosis.

Suppression of tumor growth and apoptosis induction by pomegranate seed nano-emulsion in mice bearing solid Ehrlich carcinoma cells

Despite the high antioxidant and penetration ability of pomegranate seed oil (PSO), the in vivo antitumor activity of PSO nano-emulsion has not been well investigated. Therefore, this study was undertaken to estimate the antitumor activity and safety of PSO nano-emulsion in mice bearing Ehrlich solid carcinoma cells. For tumor inoculation, about 2 × 10⁶ viable Ehrlich tumor cells (200 µl) were implanted intramuscularly in the left thigh of hind leg. Once a solid tumor appears on the 10th day of transplantation; the mice were randomly divided into five groups (5 animals/group). Characterization of the PSO nano-emulsion using a Zeta sizer Malvern instrument and transmission electron microscope (TEM) revealed that the PSO nano-droplets were well dispersed with an average particle size of 8.95 nm and a spherical shape. Treatment with PSO nano-emulsions caused a significant reduction in the tumor size and weight, in a dose dependent manner, compared to tumor control group. Marked dose dependent elevations in the DNA damage level together with significant increases in the tumor suppressor p53, Bax and Caspase genes and reductions in the anti-apoptotic Bcl2 gene were also observed in the tumor tissue of mice given PSO nano-emulsions. Histological examination also revealed apoptosis and necrosis of tumor cells and tumor infiltration with inflammatory cells after PSO nano-emulsion treatment. However, high DNA damage was noticed in the liver and kidney tissues of mice given the highest dose of PSO nano-emulsion (400 mg/kg). Therefore, we concluded that PSO nano-emulsion exhibited a potent antitumor activity through induction of DNA breaks that triggers apoptosis of tumor cells but the highest dose caused genotoxicity to liver and kidney tissues, thus it is recommended to use doses lower than 400 mg/kg of PSO nano-emulsion as an alternative drugs for chemotherapy.

Dynamic CT and Gadoxetic Acid-enhanced MRI Characteristics of P53-mutated Hepatocellular Carcinoma

Background Imaging markers of hepatocellular carcinoma (HCC) on the basis of molecular classification are important for predicting malignancy grade and prognosis. P53-mutated HCC is a major aggressive subtype; however, its imaging characteristics have not been clarified. Purpose To clarify the imaging characteristics of P53-mutated HCC at dynamic CT and gadoxetic acid-enhanced MRI that are correlated with its clinical features, pathologic findings, and prognosis. Materials and Methods In this retrospective single-center study, patients with surgically resected HCC between January 2015 and May 2018 in a university hospital were evaluated. HCC was classified into P53-mutated HCC and non-P53-mutated HCC using immunostaining. Dynamic CT and gadoxetic acid-enhanced MRI findings, clinical features, pathologic findings, and prognosis were compared using Mann-Whitney test, χ² test, multivariable regression analysis, receiver operating characteristic analysis, Kaplan-Meier method, and log-rank test. Immunohistochemical expression of P53, organic anion transporting polypeptide 1B3 (OATP1B3), and CD34 were evaluated, and the correlations were analyzed using the Pearson correlation test. Results In total, 149 patients (mean age, 67 years ± 9 [SD]; 103 men) with 173 HCCs were evaluated. P53-mutated HCC (n = 28) demonstrated higher serum α-fetoprotein (median, 127.5 ng/mL vs 5.5 ng/mL; P < .001), larger size (40.4 mm ± 29.7 vs 26.4 mm ± 20.5; P = .001), and higher rates of poorly differentiated HCC (22 of 28 [79%] vs 24 of 145 [17%]; P < .001). Dilated vasculature in the arterial phase of dynamic CT (odds ratio, 14; 95% CI: 3, 80; P = .002) and a lower relative enhancement ratio in the hepatobiliary phase (odds ratio, 0.05; 95% CI: 0.01, 0.34; cutoff value, 0.69; P = .002) independently predicted P53-mutated HCC. OATP1B3 expression and P53 expression were inversely correlated (P = .002; R = -0.24). Five-year overall survival was worse for P53-mutated HCC (50.0% vs 72.6%; P = .02). Conclusion Dilated vasculature at the arterial phase of dynamic CT and a lower relative enhancement ratio at the hepatobiliary phase of gadoxetic acid-enhanced MRI were useful markers for P53-mutated hepatocellular carcinoma with poor prognosis. © RSNA, 2022 Online supplemental material is available for this article.

p53 immunohistochemistry in endometrial cancer: clinical and molecular correlates in the PORTEC-3 trial

Standard molecular classification of endometrial cancers (EC) is now endorsed by the WHO and identifies p53-abnormal (p53abn) EC as the subgroup with the poorest prognosis and the most likely to benefit from adjuvant chemo(radio)therapy. P53abn EC are POLE wildtype, mismatch repair proficient and show abnormal immunohistochemical (IHC) staining for p53. Correct interpretation of routinely performed p53 IHC has therefore become of paramount importance. We aimed to comprehensively investigate abnormal p53 IHC patterns and their relation to clinicopathological and molecular features. Tumor material of 411 molecularly classified high-risk EC from consenting patients from the PORTEC-3 clinical trial were collected. p53 IHC was successful in 408 EC and was considered abnormal when the tumor showed a mutant expression pattern (including subclonal): overexpression, null or cytoplasmic. The presence of pathogenic mutations was determined by next generation sequencing (NGS). Abnormal p53 expression was observed in 131/408 (32%) tumors. The most common abnormal p53 IHC pattern was overexpression (n = 89, 68%), followed by null (n = 12, 9%) and cytoplasmic (n = 3, 2%). Subclonal abnormal p53 staining was observed in 27 cases (21%), which was frequently but not exclusively, associated with POLE mutations and/or MMRd (n = 22/27; p < 0.001). Agreement between p53 IHC and TP53 NGS was observed in 90.7%, resulting in a sensitivity and specificity of 83.6% and 94.3%, respectively. Excluding POLEmut and MMRd EC, as per the WHO-endorsed algorithm, increased the accuracy to 94.5% with sensitivity and specificity of 95.0% and 94.1%, respectively. Our data shows that awareness of the abnormal p53 IHC patterns are prerequisites for correct EC molecular classification. Subclonal abnormal p53 expression is a strong indicator for POLEmut and/or MMRd EC. No significant differences in clinical outcomes were observed among the abnormal p53 IHC patterns. Our data support use of the WHO-endorsed algorithm and combining the different abnormal p53 IHC patterns into one diagnostic entity (p53abn EC).

Six autoantibodies as potential differential biomarkers of hepatocellular carcinoma vs. liver cirrhosis and chronic hepatitis: A prospective multi‑institutional study

Serum autoantibodies respond not only to tumor-associated antigens of hepatocellular carcinoma (HCC) but also to those of liver cirrhosis (LC) and chronic hepatitis (CH). The present prospective multi-institutional study evaluated the diagnostic properties of six autoantibodies in distinguishing HCC from LC and CH. A total of 416 participants were enrolled: 149 With HCC, 76 with LC, 103 with CH and 88 healthy controls. Titers of serum autoantibodies to Sui1, RalA, p62, p53, c-myc and NY-ESO-1 were determined using enzyme-linked immunosorbent assays. All six antibodies were positive for HCC: s-Sui1-Abs (44%), s-RalA-Abs (23%), s-p62-Abs (21%), s-p53-Abs (13%), s-c-myc-Abs (11%) and s-NY-ESO-1-Abs (6%). The positivity rates of all six antibodies combined were 5% for healthy controls, 52% for CH, 58% for LC and 66% for HCC. The positivity rates of s-Sui1-Abs, s-RalA-Abs and s-p53-Abs were higher for HCC compared with those of LC and CH. However, the positivity rates of s-p62-Abs, s-c-myc-Abs and s-NY-ESO-1-Abs for HCC were not higher compared with those for LC and CH. Overall, autoantibodies were useful in differentiating patients with HCC from healthy individuals. However, they were not specific to HCC and were also present in the sera of individuals with CH and LC. These autoantibodies may be induced during the development of HCC. Clinical trial registration number: UMIN000014530 (date of registration 2011/07/11).

Monocentric evaluation of Ki-67 labeling index in combination with a modified RPA score as a prognostic factor for survival in IDH-wildtype glioblastoma patients treated with radiochemotherapy

Purpose

The prognosis for glioblastoma patients remains dismal despite intensive research on better treatment options. Molecular and immunohistochemical markers are increasingly being investigated as understanding of their role in disease progression grows. O(6)-methylguanine-DNA methyltransferase (MGMT) promoter methylation has been shown to have prognostic and therapeutic relevance for glioblastoma patients. Other markers implicated in tumor formation and/or malignancy are p53, Alpha thalassemia/mental retardation syndrome X-linked (ATRX), Epidermal Growth Factor Receptor splice variant III (EGFRvIII), and Ki-67, with loss of nuclear ATRX expression and lower Ki-67 index being associated with prolonged survival. For p53 and EGFRvIII the data are contradictory. Our aim was to investigate the markers mentioned above regarding progression-free (PFS) and overall survival (OS) to evaluate their viability as independent prognostic markers for our patient collective.

Methods

In this retrospective study, we collected data on patients undergoing radiotherapy due to isocitrate dehydrogenase (IDH) wildtype glioblastoma at a single university hospital between 2014 and 2020.

Results

Our findings confirm Ki-67 labeling index ≤ 20% as an independent prognostic factor for prolonged PFS as well as MGMT promoter methylation for both prolonged PFS and OS, in consideration of age and Eastern Cooperative Oncology Group (ECOG) status, chemotherapy treatment, and total radiation dose for PFS as well as additionally sex, resection status, and receipt of treatment for progression or recurrence for OS. Additionally, Ki-67 labeling index ≤ 20% showed a significant correlation with prolonged OS in univariate analysis. Modification of the recursive partitioning analysis (RPA) score to include Ki-67 labeling index resulted in a classification with the possible ability to distinguish long-term-survivors from patients with unfavorable prognosis.

Conclusion

MGMT promoter methylation and Ki-67 labeling index were independent predictors of survival in our collective. We see further studies pooling patient collectives to reach larger patient numbers concerning Ki-67 labeling index as being warranted.

Supplementary Information

The online version of this article (10.1007/s00066-022-01959-6) contains supplementary material, which is available to authorized users.

Aflatoxin B1 DNA-Adducts in Hepatocellular Carcinoma from a Low Exposure Area

Aflatoxin B1 (AFB1) is a class 1 carcinogen with an ascertained role in the development of hepatocellular carcinoma (HCC) in high exposure areas. Instead, this study aimed to assay whether chronic/intermittent, low-dose AFB1 consumption might occur in low-exposure geographical areas, ultimately accumulating in the liver and possibly contributing to liver cancer. AFB1-DNA adducts were assayed by immunostaining in liver tissues from three Italian series of twenty cirrhosis without HCC, 131 HCC, and 45 cholangiocarcinoma, and in an AFB1-induced HCC rat model. CD68, TP53 immunostaining, and TP53 RFLP analysis of R249S transversion were used to characterize cell populations displaying AFB1-DNA adducts. Twenty-five HCCs displayed AFB1-adducts both in neoplastic hepatocytes and in cells infiltrating the tumor and non-tumor tissues. Nuclear immunostaining was observed in a few cases, while most cases showed cytoplasmic immunostaining, especially in CD68-positive tumor-infiltrating cells, suggestive for phagocytosis of dead hepatocytes. Similar patterns were observed in AFB1-induced rat HCC, though with higher intensity. Cholangiocarcinoma and cirrhosis without HCC did not displayAFB1-adducts, except for one case. Despite not providing a causal relationship with HCC, these findings still suggest paying attention to detection and control measures for aflatoxins to ensure food safety in low exposure areas.

PCNA-associated factor (KIAA0101/PCLAF) overexpression and gene copy number alterations in hepatocellular carcinoma tissues

Background

PCNA-associated factor, the protein encoded by the KIAA0101/PCLAF gene, is a cell-cycle regulated oncoprotein that regulates DNA synthesis, maintenance of DNA methylation, and DNA-damage bypass, through the interaction with the human sliding clamp PCNA. KIAA0101/PCLAF is overexpressed in various cancers, including hepatocellular carcinoma (HCC). However, it remains unknown whether KIAA0101/PCLAF overexpression is coupled to gene amplification in HCC.

Methods

KIAA0101/PCLAF mRNA expression levels were assessed by quantitative real-time PCR (qRT-PCR) in 40 pairs of snap-frozen HCC and matched-non-cancerous tissues. KIAA0101/PCLAF gene copy numbers were evaluated by droplet digital PCR (ddPCR) in 36 pairs of the tissues, and protein expression was detected by immunohistochemistry (IHC) in 81 pairs of formalin-fixed paraffin-embedded (FFPE) tissues. The KIAA0101/PCLAF gene copy number alteration and RNA expression was compared by Spearman correlation. The relationships between KIAA0101 protein expression and other clinicopathological parameters, including Ki-67, p53, and HBsAg protein expression in HCC tissues, were evaluated using Chi-square test.

Results

Our results demonstrated that KIAA0101/PCLAF mRNA levels were significantly higher in HCC than in the matched-non-cancerous tissues (p < 0.0001). The high KIAA0101/PCLAF mRNA levels in HCC were associated with poor patient survival. The KIAA0101/PCLAF gene was not amplified in HCC, and KIAA0101/PCLAF gene copy numbers were not associated with KIAA0101/PCLAF transcript levels. KIAA0101 protein was overexpressed in the majority of HCC tissues (77.8%) but was not detectable in matched-non-cancerous tissues. Significant correlations between the expression of KIAA0101 protein in HCC tissues and p53 tumor suppressor protein (p = 0.002) and Ki-67 proliferation marker protein (p = 0.017) were found. However, KIAA0101 protein levels in HCC tissues were not correlated with patient age, tumor size, serum AFP level, or the HBsAg expression.

Conclusions

KIAA0101/PCLAF mRNA and protein overexpression is frequently observed in HCC but without concurrent KIAA0101/PCLAF gene amplification. Significant correlations between the expression of KIAA0101 protein and p53 and Ki-67 proteins were observed in this study. Thus, detection of KIAA0101/PCLAF mRNA/protein might be used, along with the detection of p53 and Ki-67 proteins, as potential biomarkers to select candidate patients for further studies of novel HCC treatment related to these targets.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-021-07994-3.

Sarcomatoid hepatocellular carcinoma is distinct from ordinary hepatocellular carcinoma: Clinicopathologic, transcriptomic and immunologic analyses

Sarcomatoid hepatocellular carcinoma (SHCC), which was a rare histological subtype of hepatocellular carcinoma (HCC), is currently subclassified as poorly differentiated HCC because of insufficient evidence to define SHCC as a subtype of HCC. We aimed to assess the feasibility of classifying SHCC as a histological subtype of HCC by comprehensively identifying novel and distinct characteristics of SHCC compared to ordinary HCC (OHCC). Fifteen SHCCs (1.4%) defined as HCC with at least a 10% sarcomatous component, 15 randomly disease-stage-matched OHCCs and 163 consecutive OHCCs were extracted from 1106 HCCs in the Pathology Database (1997-2019) of our hospital. SHCC patients showed poor prognosis, and the tumors could be histologically subclassified into the pleomorphic, spindle and giant cell types according to the subtype of carcinomas with sarcomatoid or undifferentiated morphology in other organs. The transcriptomic analysis revealed distinct characteristics of SHCC featuring the upregulation of genes associated with epithelial-to-mesenchymal transition and inflammatory responses. The fluorescent multiplex immunohistochemistry results revealed prominent programmed death-ligand 1 (PD-L1) expression on sarcomatoid tumor cells and higher infiltration of CD4⁺ and CD8⁺ T cells in SHCCs compared to OHCCs. The density of CD8⁺ T cells in the nonsarcomatous component of SHCCs was also higher than that in OHCCs. In conclusion, the comprehensive analyses in our study demonstrated that SHCC is distinct from OHCC in terms of clinicopathologic, transcriptomic and immunologic characteristics. Therefore, it is reasonable to consider SHCC as a histological subtype of HCC.

The Clinical and Prognostic Implications of Pluripotent Stem Cell Markers Expression and Their Correlation with the WNT signal pathway in Hepatocellular Carcinoma

Objectives:

This study aimed to investigate the expression of SOX2, SOX9, p53, and β-catenin in hepatocellular carcinoma (HCC) and their correlation with clinicopathological parameters of prognostic importance.

Materials and Methods:

Seventy-five patients were enrolled in this study. All patients had full clinical and follow-up data and available paraffin blocks. Immunohistochemical analysis was performed and correlated with clinicopathological factors and patient survival.

Results:

We detected the positive expression of SOX2, SOX9, p53, and β-catenin in 76%, 50.7%, 50.7%, and 77.9% of HCC specimens respectively. All studied markers showed a significant increase in the expression in tumor tissue specimens compared to non-tumor tissue. Both SOX2 and SOX9 expressions were significantly associated with adverse prognostic factors in HCC. Significant positive correlations were found between SOX2 and SOX9 and both p53 and β-catenin expression (r= 0.528, 0.485 and; r = 0.253, 0.327, respectively; p< 0.0001 for both of them). Regarding survival, we found that HCC patients with positive SOX2 and SOX9 expressions had significantly shorter overall survival (p=0.0001, each). Additionally, larger tumor size, tumor grade, high stage, tumor multiplicity, presence of cirrhosis, tumor necrosis, high p53 expression, and positive β-catenin expression were independent predictors of worse survival. A multivariate Cox analysis revealed that tumor grade, stage, p53, and SOX2 expression were independent predictors of unfavorable prognosis in overall survival (p=0.0001, p=0.0001,p=0.033; and p=0.003, respectively).

Conclusions:

Our findings might provide an insight into SOX2 and SOX9’s role in HCC and suggest that SOX2 might be targeted for HCC therapy.

Fast Screening of Whole Blood and Tumor Tissue for Bladder Cancer Biomarkers Using Stochastic Needle Sensors

Bladder cancer is one of the most common urologic malignancies, which is more frequent in men than in women. The early diagnosis for this type of cancer still remains a challenge, therefore, the development of a fast screening test for whole blood and tumor tissue samples may save lives. Four biomarkers, p53, E-cadherin, bladder tumor antigen (BTA), and hyaluronic acid were considered for the screening tests using stochastic needle sensors. Three stochastic needle sensors, based on graphite powder and modified with three types of chitosan, were designed and characterized for the screening test. The proposed sensors showed low limits of quantification, and high sensitivity and selectivity levels. The recoveries of p53, E-cadherin, BTA, and hyaluronic acid in whole blood samples and tissue samples were higher than 95.00% with a relative standard deviation lower than 1.00%.

Evaluation of p53 and Its Target Gene Expression as Potential Biomarkers of Cholangiocarcinoma in Thai Patients

BACKGROUND

Cholangiocarcinoma (CCA), a common cancer in northeastern Thailand, is a severe disease with poor prognosis and short survival time following diagnosis. DNA damage in CCA is believed to be caused by liver fluke infection in combination with exposure to carcinogens. p53, a tumor suppressor, is the most mutated gene in human cancers including liver fluke-associated CCA. Hence, expression patterns of p53 and its target genes may be useful for diagnosis and/or prognosis of CCA patients.

METHODS

Differential mRNA expression of p53 and its target genes, namely, FUCA1, ICAM2 MDM2, p21, PAI-1, S100A9, and WIP1 in CCA tissue samples (n = 30) relative to matched adjacent non-tumor tissues was determined by quantitative RT-PCR and compared to clinicopathological features. Level of p53 protein was determined by immunohistochemistry and correlated with the expression of its target genes.

RESULTS

Immunohistochemistry showed elevation of p53 protein level in 77% of the cases, while RT-PCR showed downregulation of p53 mRNA and its seven target genes in 23% and 47-97% of the samples. PAI-1 was down-regulated in almost all CCA samples, thus highlighting it as a potential diagnostic marker for CCA. However, no significant clinical associations were found except for down-regulation of WIP1 that was significantly correlated with non-papillary type tissue (p-value = 0.001) and with high p53 protein level (p-value = 0.007).

CONCLUSION

Our results demonstrated statistically significant association between down-regulation of WIP1 with non-papillary type and with high p53 protein level, and PAI-1 was down-regulated in almost all CCA. Therefore, expression level of WIP1 and PAI-1 may be useful for predicting p53 functional status and as a potential diagnostic marker of CCA, respectively.

Pattern of nucleotide variants of TP53 and their correlation with the expression of p53 and its downstream proteins in a Sri Lankan cohort of breast and colorectal cancer patients

Background

Breast cancer (BC) is known to be the most common malignancy in females whereas colorectal cancer (CRC) incidence also higher in both genders in Sri Lanka. TP53 is an important tumour suppressor gene and its somatic mutations are reported in approximately 27% of BC and 43% of CRC cases. Analysis of TP53 gene variants not only provides clues for the aetiology of the tumour formation, but also has an impact on treatment efficacy. The current study was conducted to investigate the pattern of TP53 variants in patients with BC and CRC from Sri Lanka.

Methods

30 patients with BC, 21 patients with CRC and an equal number of healthy controls were screened for mutational status of TP53 by polymerase chain reaction (PCR) followed by direct sequencing. In addition, a subset of these samples were analysed for the protein expression of p53 and comparison made with the mutational status of TP53. We also analysed the protein expression of p21 and MDM2 as potential indicators of p53 functional status and compared it with the protein expression of p53. Additionally, hotspot codons of the KRAS, BRAF and PIK3CA genes were also analysed in a subset of CRC patients.

Results

Twenty seven sequence variants, including several novel variants in the TP53 gene were found. Nine BC and seven CRC tumour samples carried pathogenic TP53 variants. Pathogenic point missense variants were associated with strong and diffuse positive staining for p53 by immunohistochemistry (IHC), whereas, wild type TP53 showed complete absence of positive IHC staining or rare positive cells, regardless of the type of cancer. There was no direct correlation between p21 or MDM2 expression and p53 expression in either BCs or CRCs. Four of the CRC patients had pathogenic hotspot variants in KRAS; three of them were on codon 12 and one was on codon 61.

Conclusion

The prevalence of pathogenic somatic TP53 variants was 31 and 33.33% in the studied BC and CRC cohorts respectively. All of them were located in exons 5–8 and the pathogenic missense variants were associated with strong immuno-positive staining for p53.

Needle stochastic sensors for on-site fast recognition and quantification of biomarkers for gastric cancer in biological samples

N-Doped graphenes recognised CA19-9, CEA, and p53 in biological samples.

Effect of Vitamin D on Relapse-Free Survival in a Subgroup of Patients with p53 Protein-Positive Digestive Tract Cancer: A Post Hoc Analysis of the AMATERASU Trial

BACKGROUND

The AMATERASU randomized trial of vitamin D3 supplementation (2,000 IU/day; UMIN000001977) showed the potential benefit of vitamin D in a subgroup of patients with digestive tract cancer. By conducting post hoc analyses of this trial, we further explored whether subgroups stratified by expression levels of p53, vitamin D receptor (VDR), and Ki-67 modify the effect of vitamin D supplementation.

METHODS

The primary outcome was relapse-free survival (RFS). On IHC using pathologic specimens, the degree of p53 protein expression parallel with TP53 missense mutations was classified as p53 positive (>10%) and p53 negative (≤10%). In addition, VDR and Ki-67 expression levels were divided into quartiles.

RESULTS

The p53 status of 372 patients' pathologic specimens was evaluated. In a subgroup of patients with p53-positive cancer (n = 226), 5-year RFS was 79% in the vitamin D group, which was significantly higher than the 57% in the placebo group (HR, 0.52; 95% confidence interval, 0.31-0.88; P = 0.02). In the subgroup of patients with p53-negative cancer, 5-year RFS in the vitamin D group versus placebo group was 72% versus 84% (not significantly different), respectively. Effect modification by p53 positivity was significant (P _interaction = 0.02). However, no significant effect modification by either VDR or Ki-67 was observed.

CONCLUSIONS

These results generate a hypothesis that vitamin D supplementation may improve RFS in patients with p53-positive digestive tract cancer.

IMPACT

The results are still preliminary, but potentially important, because TP53 is the most frequently mutated gene across cancers at all sites.

Oncolytic Adenovirus-A Nova for Gene-Targeted Oncolytic Viral Therapy in HCC

Hepatocellular carcinoma (HCC) is one of the most frequent cancers worldwide, particularly in China. Despite the development of HCC treatment strategies, the survival rate remains unpleasant. Gene-targeted oncolytic viral therapy (GTOVT) is an emerging treatment modality-a kind of cancer-targeted therapy-which creates viral vectors armed with anti-cancer genes. The adenovirus is a promising agent for GAOVT due to its many advantages. In spite of the oncolytic adenovirus itself, the host immune response is the determining factor for the anti-cancer efficacy. In this review, we have summarized recent developments in oncolytic adenovirus engineering and the development of novel therapeutic genes utilized in HCC treatment. Furthermore, the diversified roles the immune response plays in oncolytic adenovirus therapy and recent attempts to modulate immune responses to enhance the anti-cancer efficacy of oncolytic adenovirus have been discussed.

Involvement of increased p53 expression in the decrease of mitochondrial DNA copy number and increase of SUVmax of FDG-PET scan in esophageal squamous cell carcinoma

We appraised Warburg effect through analysis of mitochondrial DNA (mtDNA) copy number and maximum standard uptake value (SUV_max) of ¹⁸F-fluorodeoxyglucose positron emission tomography (FDG-PET) scan and their alterations in esophageal squamous cell carcinoma (ESCC). Later T-status and longer longitudinal tumor length were associated with lower mtDNA^ESCC copy number (p < .05) but higher SUV_max-ESCC (p < .05), respectively. Lower mtDNA^ESCC copy number correlated with higher SUV_max-ESCC, reciprocally (p < .05). ESCCs expressing mutant p53 protein had lower mtDNA^ESCC copy number (p = .056) but higher SUV_max-ESCC (p = .046). We conclude that mutant p53 protein may be involved in the Warburg effect of ESCC.

TP53 missense mutation is associated with increased tumor-infiltrating T cells in primary prostate cancer

The makeup of the tumor immune microenvironment may be associated with tumor somatic genomic alterations and plays a key role in tumor progression and response to immunotherapy. We examined the association of tumor-infiltrating T-cell density with TP53 status in surgically treated primary prostate cancer using 3 independent tissue microarray sets, including one set of tumors from grade-matched patients of European American or African American ancestry (n = 391), a retrospective case-cohort of intermediate- and high-risk patients enriched for adverse outcomes (n = 267), and a set of tumors with primary Gleason pattern 5 (n = 77). The presence of TP53 missense mutation, indicated by p53 nuclear accumulation using a genetically validated assay, was significantly associated with increased CD3+ T-cell density (median, 341 versus 231 CD3+ T cells/mm²; P = .004) in the matched European American and African American ancestry patient sets. The same association was present in patients of both ancestries when analyzed separately, despite the fact that p53 nuclear accumulation was less frequent among African American compared with European American tumors (7% versus 3%, P = .2). The validation cohorts of intermediate/high-risk and primary Gleason pattern 5 patients corroborated the association of increased CD3+ T-cell density with presence of p53 nuclear accumulation. In a pooled analysis of all sets, adjusting for clinicopathological variables, CD3+ and CD8+, but not FOXP3+, T-cell densities remained significantly higher in tumors with p53 nuclear accumulation compared with those without. TP53 mutation is associated with higher tumor-infiltrating T-cell density, which may be relevant in future clinical trials of immunotherapy in prostate cancer.

Overexpression of p53 in extra large (more than 10 cm) hepatocellular carcinoma

Background: Extra large hepatocellular carcinoma (HCC) of >10 cm managed in our center shows a specific characteristic in tropical regions. This type of HCC exhibits distinct p53 expression. This study aimed to determine the association between p53 expression and tumor size and behavior. Method: Subjects with HCC who underwent surgical resection in our hospital during 2012–2015 were enrolled in thisstudy. Subject’s characteristics, tumor size, histopathology findings, and tumor behavior were variables observed. Animmunohistochemical study on p53 expression was conducted to determine its association with those variables.Results: This study involved 38 subjects with tumor size ranging from 3 cm to 25 cm in diameter and 20 subjects (52.8%) with tumor size ranging from 10 cm to 25 cm in diameter. Only 13 samples were evaluated for p53 expression. Five subjects with >10 cm (extra large) tumor showed highly/overexpressed p53 (intensity>50%), two subjects with strong p53 expression (intensity>5%–50%), and two subjects with weak expression. Three subjects with <10 cm (large) tumor showed strong expression of p53 (5%–9%) and a subject with 3 cm tumor showed weak p53 expression (<5%). Highly expressed p53 was found in patients with microvascular invasion, inflammatory response, mitosis, and necrosis.Conclusion: Overexpression of p53 was associated with extra large and poorly differentiated HCC.

Wild-type p53 oligomerizes more efficiently than p53 hot-spot mutants and overcomes mutant p53 gain-of-function via a "dominant-positive" mechanism

Human p53 protein acts as a transcription factor predominantly in a tetrameric form. Single residue changes, caused by hot-spot mutations of the TP53 gene in human cancer, transform wild-type (wt) p53 tumor suppressor proteins into potent oncoproteins - with gain-of-function, tumor-promoting activity. Oligomerization of p53 allows for a direct interplay between wt and mutant p53 proteins if both are present in the same cells - where a mutant p53's dominant-negative effect known to inactivate wt p53, co-exists with an opposite mechanism - a "dominant-positive" suppression of the mutant p53's gain-of-function activity by wt p53. In this study we determine the oligomerization efficiency of wt and mutant p53 in living cells using FRET-based assays and describe wt p53 to be more efficient than mutant p53 in entering p53 oligomers. The biased p53 oligomerization helps to interpret earlier reports of a low efficiency of the wt p53 inactivation via the dominant-negative effect, while it also implies that the "dominant-positive" effect may be more pronounced. Indeed, we show that at similar wt:mutant p53 concentrations in cells - the mutant p53 gain-of-function stimulation of gene transcription and cell migration is more efficiently inhibited than the wt p53's tumor-suppressive transactivation and suppression of cell migration. These results suggest that the frequent mutant p53 accumulation in human tumor cells does not only directly strengthen its gain-of-function activity, but also protects the oncogenic p53 mutants from the functional dominance of wt p53.

Histology-dependent prognostic role of pERK and p53 protein levels in early-stage non-small cell lung cancer

Lung tumors represent a major health problem. In early stage NSCLC tumors, surgical resection is the preferred treatment, but 30-55% of patients will relapse within 5 years after surgery. Thus, the identification of prognostic biomarkers in early stage NSCLC patients, especially those which are therapeutically addressable, is crucial to enhance survival of these patients. We determined the immunohistochemistry expression of key proteins involved in tumorigenesis and oncogenic signaling, p53, EGFR, pAKT and pERK, and correlated their expression level to clinicopathological characteristics and patient outcome. We found EGFR expression is higher in the squamous cell carcinomas than in adenocarcinomas (p=0.043), and that nuclear p53 staining correlated with lower differentiated squamous tumors (p=0.034). Regarding the prognostic potential of the expression of these proteins, high pERK levels proved to be an independent prognostic factor for overall (p<0.001) and progression-free survival (p<0.001) in adenocarcinoma patients, but not in those from the squamous histology, and high p53 nuclear levels were identified as independent prognostic factor for progression-free survival (p=0.031) only in squamous cell carcinoma patients. We propose a role as early prognostic biomarkers for pERK protein levels in adenocarcinoma, and for nuclear p53 levels in squamous cell lung carcinoma. The determination of these potential biomarkers in the adequate histologic context may predict the outcome of early stage NSCLC patients, and may offer a therapeutic opportunity to enhance survival of these patients.

p53 as a Dichotomous Regulator of Liver Disease: The Dose Makes the Medicine

Lifestyle-related disorders, such as the metabolic syndrome, have become a primary risk factor for the development of liver pathologies that can progress from hepatic steatosis, hepatic insulin resistance, steatohepatitis, fibrosis and cirrhosis, to the most severe condition of hepatocellular carcinoma (HCC). While the prevalence of liver pathologies is steadily increasing in modern societies, there are currently no approved drugs other than chemotherapeutic intervention in late stage HCC. Hence, there is a pressing need to identify and investigate causative molecular pathways that can yield new therapeutic avenues. The transcription factor p53 is well established as a tumor suppressor and has recently been described as a central metabolic player both in physiological and pathological settings. Given that liver is a dynamic tissue with direct exposition to ingested nutrients, hepatic p53, by integrating cellular stress response, metabolism and cell cycle regulation, has emerged as an important regulator of liver homeostasis and dysfunction. The underlying evidence is reviewed herein, with a focus on clinical data and animal studies that highlight a direct influence of p53 activity on different stages of liver diseases. Based on current literature showing that activation of p53 signaling can either attenuate or fuel liver disease, we herein discuss the hypothesis that, while hyper-activation or loss of function can cause disease, moderate induction of hepatic p53 within physiological margins could be beneficial in the prevention and treatment of liver pathologies. Hence, stimuli that lead to a moderate and temporary p53 activation could present new therapeutic approaches through several entry points in the cascade from hepatic steatosis to HCC.

Synergistic inhibitory effects on hepatocellular carcinoma with recombinant human adenovirus Aspp2 and oxaliplatin via p53-independent pathway in vitro and in vivo

The present study was designed to investigate the synergistic inhibitory effects on hepatocellular carcinoma with recombinant human adenovirus Aspp2 (Aspp2-ad) and oxaliplatin via p53-independent pathway in vitro and in vivo. After being treated with Aspp2-ad and/or oxaliplatin for 24-48 h, HepG2P53-/- and Hep3B cells showed a significant growth inhibition compared with vehicle control. Combination group showed a synergetic effect, the inhibitory rates were all above 80% at 48 h point in HepG2P53-/- and Hep3B cells. The apoptotic cell numbers of Aspp2-ad and/or oxaliplatin treatment groups were increased remarkably, especially for the combined therapy group in the liver cancer cells. The Hep3B xenograft experiment also showed similar inhibition of Aspp2-ad and/or oxaliplatin to the in vitro experiment. H&E results showed that combination group had the least mitotic indexes and the most necrosis. The immunohistochemistry results showed that PCNA, CD31 expression decreased greatly in treatment groups. These results suggested that Aspp2-ad might inhibit proliferation and vascular growth of hepatocarcinoma. Aspp2 induced apoptosis protein expression in Aspp2-ad and combination groups, the Aspp2, Bax and activation of caspase-3 expression increased greatly both in vitro and in vivo. But interestingly, the autophagy proteins showed different responses not only in HepG2P53-/- and Hep3B cells but also in vitro and in vivo. We found that Aspp2-ad downregulated the p-ERK, p-STAT3 expression, the synergistic effects were observed in combination group, while there was not response of mTOR to Aspp2-ad. In conclusion, Aspp2-ad, in P53-independent manner, regulated ERK and STAT3 signal moleculars to inhibit hepatocarcinoma in coordination with oxaliplatin by influencing the protein expression of proliferation, apoptosis, autophagy and vascular growth. Aspp2-ad has the potential to be developed in gene therapy for HCC, especially for P53 deletion or mutation in HCC.

Analytic, Preanalytic, and Clinical Validation of p53 IHC for Detection of TP53 Missense Mutation in Prostate Cancer

Purpose:TP53 missense mutations may help to identify prostate cancer with lethal potential. Here, we preanalytically, analytically, and clinically validated a robust IHC assay to detect subclonal and focal TP53 missense mutations in prostate cancer.Experimental Design: The p53 IHC assay was performed in a CLIA-accredited laboratory on the Ventana Benchmark immunostaining system. p53 protein nuclear accumulation was defined as any p53 nuclear labeling in >10% of tumor cells. Fifty-four formalin-fixed paraffin embedded (FFPE) cell lines from the NCI-60 panel and 103 FFPE prostate cancer tissues (88 primary adenocarcinomas, 15 metastases) with known TP53 mutation status were studied. DU145 and VCaP xenografts were subjected to varying fixation conditions to investigate the effects of preanalytic variables. Clinical validation was performed in two partially overlapping radical prostatectomy cohorts.Results: p53 nuclear accumulation by IHC was 100% sensitive for detection of TP53 missense mutations in the NCI-60 panel (25/25 missense mutations correctly identified). Lack of p53 nuclear accumulation was 86% (25/29) specific for absence of TP53 missense mutation. In FFPE prostate tumors, the positive predictive value of p53 nuclear accumulation for underlying missense mutation was 84% (38/45), whereas the negative predictive value was 97% (56/58). In a cohort of men who experienced biochemical recurrence after RP, the multivariable HR for metastasis among cases with p53 nuclear accumulation compared with those without was 2.55 (95% confidence interval, 1.1-5.91).Conclusions: IHC is widely available method to assess for the presence of deleterious and heterogeneous TP53 missense mutations in clinical prostate cancer specimens. Clin Cancer Res; 23(16); 4693-703. ©2017 AACR.