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result(s) for
"p16(INK4A)"
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HPV DNA genotyping, HPV E6I mRNA detection, and p16INK4a/Ki-67 staining in Belgian head and neck cancer patient specimens, collected within the HPV-AHEAD study
by
Vermeulen, Peter
,
Pawlita, Michael
,
Lucas, Eric
in
Head and neck neoplasms
,
Human papillomavirus
,
Human papillomavirus DNA tests
2021
•Heterogeneity of HPV DNA prevalence across anatomical sites in Belgian HNC patients.•HPV16 is the predominant genotype in all HNC sites.•Estimated proportion of HPV-driven HNC (1980–2014): 30 % for OPC, 3 % for OC and LC.
The main risk factors for head and neck cancer (HNC) are tobacco and alcohol use. However, an important fraction of oropharyngeal cancer (OPC) is caused by human papillomaviruses (HPV), a subgroup with increasing incidence in several western countries.
As part of the HPV-AHEAD study, we assessed the role of HPV infection in 772 archived tissue specimens of Belgian HNC patients: 455 laryngeal (LC), 106 oral cavity (OCC), 99 OPC, 76 hypopharyngeal (HC), and 36 unspecified parts of the head and neck. All specimens were tested for HPV DNA (21 genotypes); whereof all HPV DNA-positives, all HPV DNA-negative OPCs and a random subset of HPV DNA-negatives of the other HNC-sites were tested for the presence of type-specific HPV RNA and p16INK4a over-expression.
The highest HPV DNA prevalence was observed in OPC (36.4 %), and was significantly lower (p < 0.001) in the other HNCs (OCC:7.5 %, LC:6.6 %). HPV16 was the most common HPV-genotype in all HNCs. Approximately 83.0 % of the HPV DNA-positive OPCs tested HPV RNA or p16-positive, compared to about 37.5 % and 44.0 % in OCC and LC, respectively. Estimation of the attributable fraction of an HPV infection in HNC was very similar for HPV RNA or p16 in addition to DNA-positivity; with 30 % for OPC, and 3 % for OCC and LC.
Our study confirms the heterogeneity of HPV DNA prevalence across anatomical sites in HNC, with a predominance of HPV16 in all sites. The estimated proportion of HPV-driven HNC in Belgium, during the period 1980–2014, was 10 times higher in OPC compared to OCC and LC.
Journal Article
Accuracy of high-risk HPV DNA PCR, p16(INK4a) immunohistochemistry or the combination of both to diagnose HPV-driven oropharyngeal cancer
2022
Background
The incidence of high-risk human papillomavirus (hrHPV)-driven head and neck squamous cell carcinoma, in particular oropharyngeal cancers (OPC), is increasing in high-resource countries. Patients with HPV-induced cancer respond better to treatment and consequently have lower case-fatality rates than patients with HPV-unrelated OPC. These considerations highlight the importance of reliable and accurate markers to diagnose truly HPV-induced OPC.
Methods
The accuracy of three possible test strategies, i.e. (a) hrHPV DNA PCR (DNA), (b) p16
(INK4a)
immunohistochemistry (IHC) (p16), and (c) the combination of both tests (considering joint DNA and p16 positivity as positivity criterion), was analysed in tissue samples from 99 Belgian OPC patients enrolled in the HPV-AHEAD study. Presence of HPV E6*I mRNA (mRNA) was considered as the reference, indicating HPV etiology.
Results
Ninety-nine OPC patients were included, for which the positivity rates were 36.4%, 34.0% and 28.9% for DNA, p16 and mRNA, respectively. Ninety-five OPC patients had valid test results for all three tests (DNA, p16 and mRNA). Using mRNA status as the reference, DNA testing showed 100% (28/28) sensitivity, and 92.5% (62/67) specificity for the detection of HPV-driven cancer. p16 was 96.4% (27/28) sensitive and equally specific (92.5%; 62/67). The sensitivity and specificity of combined p16 + DNA testing was 96.4% (27/28) and 97.0% (65/67), respectively. In this series, p16 alone and combined p16 + DNA missed 1 in 28 HPV driven cancers, but p16 alone misclassified 5 in 67 non-HPV driven as positive, whereas combined testing would misclassify only 2 in 67.
Conclusions
Single hrHPV DNA PCR and p16
(INK4a)
IHC are highly sensitive but less specific than using combined testing to diagnose HPV-driven OPC patients. Disease prognostication can be encouraged based on this combined test result.
Journal Article
PIK3CA Gene Mutations in HNSCC: Systematic Review and Correlations with HPV Status and Patient Survival
by
Montalvão, Pedro
,
Cochicho, Daniela
,
Magalhães, Miguel
in
1-Phosphatidylinositol 3-kinase
,
Cancer
,
Deoxyribonucleic acid
2022
PIK3CA mutations are believed to contribute to the pathogenesis of human papillomavirus (HPV)-associated head and neck squamous cell carcinomas (HNSCC). This study aims to establish the frequency of PIK3CA mutations in a Portuguese HNSCC cohort and to determine their association with the HPV status and patient survival. A meta-analysis of scientific literature also revealed widely different mutation rates in cohorts from different world regions and a trend towards improved prognosis among patients with PIK3CA mutations. DNA samples were available from 95 patients diagnosed with HNSCC at the Portuguese Institute of Oncology in Lisbon between 2010 and 2019. HPV status was established based on viral DNA detected using real-time PCR. The evaluation of PIK3CA gene mutations was performed by real-time PCR for four mutations (H1047L; E542K, E545K, and E545D). Thirty-seven cases were found to harbour PIK3CA mutations (39%), with the E545D mutation (73%) more frequently detected. There were no significant associations between the mutational status and HPV status (74% WT and 68% MUT were HPV (+); p = 0.489) or overall survival (OS) (3-year OS: WT 54% and MUT 65%; p = 0.090). HPV status was the only factor significantly associated with both OS and disease-free survival (DFS), with HPV (+) patients having consistently better outcomes (3-year OS: HPV (+) 65% and HPV (−) 36%; p = 0.007; DFS HPV (+) 83% and HPV (−) 43%; p = 0.001). There was a statistically significant interaction effect between HPV status and PIK3CA mutation regarding DFS (Interaction test: p = 0.026). In HPV (+) patients, PIK3CA wild-type is associated with a significant 4.64 times increase in the hazard of recurrence or death (HR = 4.64; 95% CI 1.02–20.99; p = 0.047). Overall, PIK3CA gene mutations are present in a large number of patients and may help define patient subsets who can benefit from therapies targeting the PI3K pathway. The systematic assessment of PIK3CA gene mutations in HNSCC patients will require further methodological standardisation.
Journal Article
Frequent genetic aberrations in the cell cycle related genes in mucosal melanoma indicate the potential for targeted therapy
2019
Background
Melanoma is one of the most aggressive cancers with extremely poor prognosis, and the median survival time for stage IV patients is approximately 6 to 8 months. Unlike cutaneous melanoma, mucosal melanoma is a rare melanoma subtype among Caucasian patients but its incidence remains as high as 22.6% among Chinese patients. Screening specific genetic variations is the guideline to select targeted drugs for the treatment of advanced melanoma, whereas the genetic variation spectrum and potential therapeutic targets for mucosal melanoma are largely unclear. It is urgent to identify promising genetic variants for mucosal melanoma so as to develop effective targeted therapies for this disease.
Methods
Tumor samples from 213 Chinese mucosal melanoma patients were involved in this study. P16
INK4a
/Cyclin D1/CDK4 copy number was examined using the QuantiGene Plex DNA assay and the correlation between abnormal copy number and clinicopathological parameters was analyzed. Patient-derived xenograft models (PDX) were performed to detect the effects of CDK4/6 inhibitors on the proliferation of mucosal melanoma cells with altered copy number of CDK4 pathway (
CDK4, Cyclin D1
and
P16
INK4
a
). The molecular mechanisms of CDK4/6 inhibitors on the proliferation of mucosal melanoma were analyzed by RNAseq.
Results
Among the 213 samples, the amplification rate of
CDK4
and
CCND1
was 47.0% and 27.7%, respectively, and the deletion rate of
P16
INK4a
was 57.7%. Patients with more than one genetic abnormality were up to 81.7%. CDK4 pathway gene copy number variation was not associated with the prognosis of patients with mucosal melanoma (P > 0.05). Drug sensitivity tests showed that AT7519, a broad-spectrum CDK inhibitor, and PD0332991, a specific CDK4/6 inhibitor, exhibited higher inhibitory effect on CDK4 signaling pathway abnormal mucosal melanoma cells-derived PDX tumors growth than CDK4 signaling pathway normal ones. RNA-seq analysis showed that CDK4 inhibitors may affect tumor proliferation through multiple signaling pathways.
Conclusions
Abnormal copy number of cell cycle related genes is frequently found in mucosal melanoma. CDK4/6 inhibitors significantly suppress the PDX tumor growth with abnormal CDK4 pathway. CDK4 signaling variations predict the effectiveness of CDK4 inhibitors in mucosal melanoma.
Journal Article
DNA methylation of the p14(ARF), RASSF1A and APC1A genes as an independent prognostic factor in colorectal cancer patients
by
Nilsson, Torbjorn K.
,
Sun, Xiao-Feng
,
Lof-Ohlin, Zarah M.
in
APC1A
,
colorectal cancer
,
CpG sites
2013
We quantitated the methylated fraction of CpG sites in the promoter regions of O-6-MGMT, p14(ARF), p16(INK4a), RASSF1A and APC1A in tumor tissue from patients with colorectal cancer (CRC) in order to determine if promoter hypermethylation of any of these genes predicts survival. DNA was isolated from 111 primary CRC and 46 matched normal colorectal mucosa samples from the same patients, obtained at primary surgery and DNA methylation was examined by Pyrosequencing (R). Follow-up time was up to 20 years. Patients showed partial promoter methylation in the following frequencies: O-6-MGMT, 34%; p14(ARF), 29%; p16(INK4a), 28%; RASSF1A, 14%; and APC1A, 27%. Normal mucosa was always unmethylated. CRC patients with methylated p14(ARF). gene promoter had significantly worse prognosis (p=0.036), whereas those with methylated O-6-MGMT had significantly better prognosis through the first 60 months post-treatment (RR 0.36; p=0.023). Methylation of one or more of the genes from the set p14(ARF), RASSF1A and APC1A, was significantly (p=0.021) associated with worse prognosis even adjusting for tumor stage and differentiation (RR 2.2, p=0.037). Thus, DNA methylation of the p14(ARF), RASSF1A and APC1A genes, diagnosed by Pyrosequencing, defines a poor prognosis subset of CRC patients independently of both tumor stage and differentiation. O-6-MGMT methylation may play a protective role.
Journal Article
Clinico-Pathological Features and Immunohistochemical Comparison of p16, p53, and Ki-67 Expression in Muscle-Invasive and Non-Muscle-Invasive Conventional Urothelial Bladder Carcinoma
by
Ashmawy, Diaa
,
Morsi, Deaa Fekri
,
Mandour, Essam
in
Archives & records
,
Biopsy
,
Bladder cancer
2023
Introduction: The identification of bladder detrusor muscle invasion in urothelial cancer is essential for prognosis and management. We studied the clinical, histological, and immunohistochemical expression of p16, p53, and Ki-67 in urothelial detrusor muscle-invasive bladder cancer (MIBC) and urothelial non-detrusor muscle-invasive bladder cancer (NMIBC) in Egyptian patients. Methods: Sixty-two bladder urothelial cancer cases obtained through TURBT were included and divided into two groups: (MIBC, stage T2) and NMIBC (T1). Tissue blocks were recut and re-examined microscopically; then, the immunostaining of p16, p53, and Ki-67 was performed to compare both groups and evaluate the 13% cut-off for Ki-67, 20% for p53, and p16 intensity in various conditions aided by telepathology technology. Results and conclusion: Hematuria was the main clinical first presentation, with no significant difference between either group. The mean age was 61.6 years, with male predominance (52 males and 10 females). The absence of papillary histological pattern was associated with a higher stage, including detrusor muscle invasion (p = 0.000). The overall average percent of p53 immunostaining was 12.9%, revealing no significant difference between MIBC and NMIBC when a cut-off of 20% was implicated. The Ki-67 expression was correlated with higher grade and muscle invasion; however, no association was found with the other two markers’ expression. The negative immunostaining of p16 was associated with low grade and NMIBC in the case of the preservation of the papillary pattern. We recommend further studies on the cut-off of widely used markers and more immunohistochemical and genetic studies on the p16(INK4A), taking into consideration the histological pattern of conventional carcinomas.
Journal Article
p16INK4a and pRb expression in laryngeal squamous cell carcinoma with and without infection by EBV or different genotypes of HPV: a retrospective study
by
Martinez-Torres, Ana Carolina
,
Vazquez-Guillen, Jose Manuel
,
Hernandez-Martinez, Silvia Judith
in
Alcohol
,
Biomarkers
,
Biomedical and Life Sciences
2023
Background
Laryngeal squamous cell carcinoma (LSCC) represents one of the principal tumors of the head and neck. Human papillomavirus (HPV) and Epstein–Barr virus (EBV) are considered risk factors for the development and the clinical prognosis of LSCC. High levels of p16
INK4a
are suggested as a surrogate marker of HPV or EBV infection in some head and neck tumors but in LSCC is still controversial. Furthermore, pRb expression may be considered an additional biomarker but it has not been clearly defined. This work aimed to compare the expression of pRb and p16
INK4a
as possible biomarkers in tumor tissues with and without infection by EBV or different genotypes of HPV from patients with LSCC.
Methods
Tumor samples from 103 patients with LSCC were previously investigated for the presence and genotypes of HPV using the INNO-LiPA line probe assay and for the infection of EBV by qPCR. p16
INK4a
and pRb expression was assessed by immunohistochemistry.
Results
Of the 103 tumor samples, expression of p16
INK4a
was positive in 55 (53.4%) and of this, 32 (56.1%) were positive for HPV whereas 11 (39.3%) were EBV positive but both without a significantly difference (
p
> 0.05). pRb expression was positive in 78 (75.7%) and a higher frequency of this expression was observed in HPV negative samples (87.0%) (
p
= 0.021) and in high-risk HPV negative samples (85.2%) (
p
= 0.010). No difference was observed when comparing pRb expression and EBV infection status (
p
> 0.05).
Conclusion
Our results support the suggestion that p16
INK4a
is not a reliable surrogate marker for identifying HPV or EBV infection in LSCC. On the other hand, most of our samples had pRb expression, which was more frequent in tumors without HPV, suggesting that pRb could indicate HPV negativity. However, more studies with a larger number of cases are required, including controls without LSCC and evaluating other molecular markers to determine the real role of p16
INK4a
and pRb in LSCC.
Journal Article
Endothelial toll‐like receptor 4 maintains lung integrity via epigenetic suppression of p16INK4a
by
Patty J. Lee
,
Taylor Ardito
,
Tien Peng
in
2.1 Biological and endogenous factors
,
Aetiology
,
aging
2019
We previously reported that the canonical innate immune receptor toll‐like receptor 4 (TLR4) is critical in maintaining lung integrity. However, the molecular mechanisms via which TLR4 mediates its effect remained unclear. In the present study, we identified distinct contributions of lung endothelial cells (Ec) and epithelial cells TLR4 to pulmonary homeostasis using genetic‐specific, lung‐ and cell‐targeted in vivo methods. Emphysema was significantly prevented via the reconstituting of human TLR4 expression in the lung Ec of TLR4−/− mice. Lung Ec‐silencing of TLR4 in wild‐type mice induced emphysema, highlighting the specific and distinct role of Ec‐expressed TLR4 in maintaining lung integrity. We also identified a previously unrecognized role of TLR4 in preventing expression of p16INK4a, a senescence‐associated gene. Lung Ec‐p16INK4a‐silencing prevented TLR4−/− induced emphysema, revealing a new functional role for p16INK4ain lungs. TLR4 suppressed endogenous p16INK4a expression via HDAC2‐mediated deacetylation of histone H4. These findings suggest a novel role for TLR4 in maintaining of lung homeostasis via epigenetic regulation of senescence‐related gene expression.
Journal Article