Middle Eastern Papillary Thyroid Cancer Research Articles

Loss of CDH16 expression is a strong independent predictor for lymph node metastasis in Middle Eastern papillary thyroid cancer

Papillary Thyroid Cancer (PTC) is the most common type of thyroid cancer. The membrane-associated glycoprotein cadherin-16 (CDH16) plays a significant role in the embryonal development of thyroid follicles and cell adhesion. Previous studies have indicated a substantial downregulation of CDH16 in PTC. However, its role in Middle Eastern PTC has not been elucidated. We analyzed a tissue microarray comprising 1606 PTC and 240 normal thyroid tissues using immunohistochemistry to assess CDH16 expression and determine its clinico-pathological associations. We also conducted BRAF and TERT mutations analyses through Sanger sequencing. Disease-free survival (DFS) was assessed using Kaplan–Meier curves. CDH16 immunostaining was seen in 100% of normal thyroid tissues but only in 9.4% of PTC tissues (p < 0.0001). The loss of CDH16 expression was associated with aggressive PTC characteristics including bilaterality, multifocality, extrathyroidal extension, tall cell variant, lymph node metastasis (LNM) and distant metastasis. Additionally a correlation between loss of CDH16 expression and BRAF and TERT mutations was identified. Intriguingly, upon conducting multivariate logistic regression analysis, CDH16 was determined to be an independent predictor for LNM (Odds ratio = 2.46; 95% confidence interval = 1.60–3.79; p < 0.0001). Furthermore, CDH16 loss was associated with a shorter DFS (p = 0.0015). However, when we further subdivided CDH16 negative patients based on the co-existence of TERT and/or BRAF mutations, we found that patients with both CDH16 negative expression and TERT mutation exhibited the shortest DFS (p < 0.0001). In conclusion, our results suggest that CDH16 protein expression could serve as a valuable diagnostic tool for PTC. Furthermore, these findings demonstrate that the loss of CDH16 expression is an independent predictor of LNM and may contribute to the aggressiveness of PTC. Therefore, downregulation of CDH16 in PTC might be a potential target for designing novel therapeutic strategies to treat PTC.

Abstract 2425: Prevalence of NTRK fusions and clinico-pathological characteristics of Middle Eastern papillary thyroid cancer revealed enrichment in BRAF wild-type PTC

Abstract Fusions involving neurotrophic tyrosine receptor kinase (NTRK) are known oncogenic drivers in a broad range of tumor types. It recently gained attention as predictor of targeted therapy, since selective NTRK inhibitor are now approved in US and Europe for patients with solid tumor harboring gene fusions. However, estimation of NTRK gene fusion/alteration frequency and its clinico-pathological characteristics in papillary thyroid cancer (PTC) is limited, especially in a population with high incidence for PTC like Middle Eastern population. This study aims to characterize the NTRK gene fusion frequency using FISH analysis and investigate the utility of pan-Trk immunohistochemistry as predictor of NTRK fusion in a large cohort of Middle Eastern PTC. FISH analysis for NTRK gene fusions as well as immunohistochemical (IHC) staining was conducted on a cohort of 315 Middle Eastern PTC. Correlation of NTRK with clinico-pathological markers and patient outcome were determined. 6.0% (19/315) patients were identified with NTRK gene fusions and significantly associated with pediatric PTC, lymph node metastasis and BRAF wild-type. Pan-Trk IHC was positive in 9.2% (29/315) and significantly associated with NTRK gene fusion with a sensitivity of 73.7% and specificity of 94.9% in this cohort. In conclusion, this study confirms the presence of NTRK fusions in Middle Eastern PTC and mostly enriched in BRAF wild-type and pediatric age group and propose the usefulness of IHC to screen for PTC patients with NTRK fusion that might benefit from TRK inhibitors. Citation Format: Abdul K. Siraj, Rong Bu, Sandeep K. Parvathareddy, Yan Kong, Padmanaban Annaiyappanaidu, Saeeda O. Ahmed, Maha Al-Rasheed, Khawla S. Al-Kuraya. Prevalence of NTRK fusions and clinico-pathological characteristics of Middle Eastern papillary thyroid cancer revealed enrichment in BRAF wild-type PTC [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 2425.

Abstract 730: Annual hazard rate of recurrence in Middle-Eastern papillary thyroid cancer over a long-term follow-up

Abstract Predicting the pattern of recurrence is necessary to establish optimal surveillance and treatment strategies. We identified patient population that remain at risk for an event and clarify changes in the hazard rate (HR) for tumor recurrence overtime in Middle Eastern patients with Papillary Thyroid Cancer (PTC). Data for 1201 PTC patients from single institute with median follow-up of 9.5 years were analyzed. Estimated HR were plotted overtime for the entire cohort, as well as for radioactive iodine (RAI) ablation in patients separately. The changes in risk were further analyzed according to clinical variable and factors predictive of early (≤ 5years) and late (&amp;gt;5 years) recurrence were explored using Cox regression analysis. Tumor recurrence was noted in 18.4% (221/1201) patients. The annualized hazard of PTC recurrence was highest during the first 5 years (2.8%), peaking between 1 - 2 years (3.7%), with a second smaller peak between 13 - 14 years (3.2%). Patients receiving RAI therapy had a lower hazard of recurrence compared to those who did not receive RAI therapy (1.5% vs 2.7%, p = 0.0001). Importantly, this difference was significant even in the intermediate-risk PTC patients (0.7% vs 2.3%; p = 0.0001). Interestingly, PTC patients who were male, aged ≥ 55 years, with lymph node involvement and advanced stage disease were still at high risk for late recurrence. In conclusion, we confirmed the validity of double-peaked time-varying pattern for risk of recurrence in Middle-Eastern PTC patients. Furthermore, according to the time distribution of recurrence hazard, we could formulate individualized treatment and surveillance plans in PTC patients. Citation Format: Abdul K. Siraj, Sandeep K. Parvathareddy, Zeeshan Qadri, Saud Azam, Felisa De Vera, Maha Al-Rasheed, Wael Haqawi, Hassan AlDossari, Khawla S. Al-Kuraya. Annual hazard rate of recurrence in Middle-Eastern papillary thyroid cancer over a long-term follow-up [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 730.

Recurrent Somatic MAP2K1 Mutations in Papillary Thyroid Cancer and Colorectal Cancer.

Mitogen-activated protein kinase kinase 1 (MAP2K1) is a dual specificity protein kinase that phosphorylates both threonine and tyrosine residues in ERK. MAP2K1 mutations have been identified in several cancers. However, their role in Middle Eastern papillary thyroid cancer (PTC) and colorectal cancer (CRC) is lacking. In this study, we evaluated the prevalence of MAP2K1 mutations in a large cohort of Middle Eastern PTC and CRC using whole-exome and Sanger sequencing technology. In the discovery cohort of 100 PTC and 100 CRC cases (comprising 50 MAPK mutant and 50 MAPK wildtype cases each), we found one MAP2K1 mutation each in PTC and CRC, both of which were MAPK wildtype. We further analyzed 286 PTC and 289 CRC MAPK wildtype cases and found three MAP2K1 mutant PTC cases and two MAP2K1 mutant CRC cases. Thus, the overall prevalence of MAP2K1 mutation in MAPK wildtype cases was 1.1% (4/336) in PTC and 0.9% (3/339) in CRC. Histopathologically, three of the four MAP2K1 mutant PTC cases were follicular variant and all four tumors were unifocal with absence of extra-thyroidal extension. All the three CRC cases harboring MAP2K1 mutation were of older age (> 50 years) and had moderately differentiated stage II/III tumors located in the left colon. In conclusion, this is the first comprehensive report of MAP2K1 somatic mutations prevalence in PTC and CRC from this ethnicity. The mutually exclusive nature of MAP2K1 and MAPK mutations suggests that each of these mutation may function as an initiating mutation driving tumorigenesis through MAPK signaling pathway.

NTRK fusion analysis reveals enrichment in Middle Eastern BRAF wild-type PTC.

Fusions involving neurotrophic tyrosine receptor kinase (NTRK) are known oncogenic drivers in a broad range of tumor types. It recently gained attention as a predictor of targeted therapy since selective NTRK inhibitors are now approved in the US and Europe for patients with solid tumors harboring gene fusions. However, estimation of NTRK gene fusion/alteration frequency and its clinicopathological characteristics in papillary thyroid cancer (PTC) is limited, especially in a population with high incidence for PTC like Middle Eastern population. This study aims to characterize the NTRK gene fusion frequency and investigate the utility of pan-Trk immunohistochemistry (IHC) as predictor of NTRK fusion in a large cohort of Middle Eastern PTC. FISH analysis for NTRK gene fusions and pan-Trk IHC was performed on 315 Middle Eastern PTCs. Correlation of NTRK gene fusion and protein expression with clinicopathological markers and patient outcome were determined. In our cohort, 6.0% (19/315) patients showed NTRK gene fusions and were significantly associated with pediatric PTC (P = 0.0143), lymph node metastasis (P = 0.0428) and BRAF WT tumors (P < 0.0001). Pan-Trk IHC was positive in 9.2% (29/315) of cases and significantly associated with NTRK fusions, with a sensitivity of 73.7% and specificity of 94.9% in this cohort. This study confirms the presence of NTRK fusions in Middle Eastern PTC which is significantly enriched in BRAF WT as well as pediatric age group and proposes the usefulness of IHC to screen for PTC patients with NTRK fusion that might benefit from TRK inhibitors.

Annual Hazard Rate of Recurrence in Middle Eastern Papillary Thyroid Cancer over a Long-Term Follow-Up.

Simple SummaryTumor recurrence is a relatively common event in papillary thyroid cancer (PTC). The aim of this study was to analyze the time-varying pattern of recurrence in PTC using annual hazard function and establish a predictive model for early and late recurrences. We found a double-peaked pattern of annual hazard of recurrence, with the risk being highest during the first 5 years after surgery. We also found distinct clinico-pathological parameters that could independently predict the occurrence of early recurrence (first 5 years) as compared to late recurrence (after 5 years). Overall, this study highlights the importance of long-term follow-up of PTC patients. Furthermore, the findings of our study could help in establishing individualized treatment and surveillance plans in PTC patients.Predicting the pattern of recurrence in papillary thyroid cancer (PTC) is necessary to establish optimal surveillance and treatment strategies. We analyzed changes in hazard rate (HR) for tumor recurrence over time in 1201 unselected Middle Eastern PTC patients. The changes in risk were further analyzed according to clinical variables predictive of early (≤5 years) and late (>5 years) recurrence using Cox regression analysis to identify patient populations that remain at risk. Tumor recurrence was noted in 18.4% (221/1201) patients. The annualized hazard of PTC recurrence was highest during the first 5 years (2.8%), peaking between 1 and 2 years (3.7%), with a second smaller peak between 13 and 14 years (3.2%). Patients receiving radioactive iodine (RAI) therapy had lower recurrence hazard compared to those who did not (1.5% vs. 2.7%, p = 0.0001). Importantly, this difference was significant even in intermediate-risk PTC patients (0.7% vs. 2.3%; p = 0.0001). Interestingly, patients aged ≥55 years and having lymph node metastasis were at persistent risk for late recurrence. In conclusion, we confirmed the validity of the double-peaked time-varying pattern for recurrence risk in Middle Eastern PTC patients and our findings could help in formulating individualized treatment and surveillance plans.

The role of HER2 overexpression in Middle Eastern papillary thyroid cancer

The role of HER2 overexpression in Middle Eastern papillary thyroid cancer

The role of HER2 overexpression in Middle Eastern papillary thyroid cancer

Background: HER2 oncogene is involved in many cancers and serves as a prognostic marker and therapeutic target in breast cancer. The purpose of this study was to learn more on the prevalence and clinical significance of HER2 overexpression and its association with clinical parameters in Middle Eastern papillary thyroid carcinoma (PTC). Methods: A tissue microarray (TMA) containing >1,000 PTC cases with follow-up data was used. TMA sections were analyzed on protein and DNA level using immunohistochemistry and fluorescence in situ hybridization (FISH). FISH analyses were performed to look for the gain or amplifications in HER2 gene. Results: Immunohistochemical analysis showed HER2 overexpression in 19.7% of our cases. Elevated expression was almost exclusively 2+ (194 tumors) and only rarely 3+ (1 tumor). No amplification was seen by FISH. Only 3% of our cases showed mildly elevated HER2 gene copy numbers not reaching the threshold for amplification. HER2 overexpression and copy number gains were unrelated to tumor stage, metastasis, patient survival and other clinical and pathological parameters. Conclusions: Our results demonstrated that HER2 overexpression occurs at relevant frequency in papillary thyroid cancer and in the absence of gene amplification. Additionally, expression of HER2 seems to hold no clinical value as prognostic factor in PTC.

Abstract 462: The role of Her2 overexpression in Middle Eastern papillary thyroid cancer

Abstract Thyroid cancer is the second most common malignancy among females in Saudi Arabia accounting for 7.4% of all cancers and 10.6% of all female malignant cancer. Among different subtypes, papillary thyroid cancer (PTC) is the most common subtype of thyroid cancer. Although the overall cancer related ten year survival rate for PTC has reached 90%, local, regional and distant metastasis does occur in 10% of cases. Therefore, in search for new therapeutic targets for PTC, we investigated the role of Her2 oncogene in PTC as this gene is known to be involved in other cancers such as breast cancer. The aim of this study was to determine the prevalence and prognostic role of Her2 overexpression in Middle Eastern papillary thyroid carcinoma by immunohistochemistry (IHC), Fluorescent In-Situ Hybridization (FISH) and clinical data. A tissue microarray (TMA) containing &amp;gt;1000 PTC cases with follow-up data was used. TMA sections were analysed at protein and DNA level using IHC and FISH. FISH analyses were performed to look for the gain or amplifications in Her2 gene. IHC analysis showed Her2 overexpression in 19.7% of our cases of PTC. Elevated expression was almost exclusively 2+ (194 tumors) and only rarely 3+ (1 tumor). Interestingly, no amplification of Her2 gene was visualized by FISH. Only 3% of our cases showed mildly elevated HER2 gene copy numbers not reaching the threshold for amplification. HER2 overexpression and copy number gains were unrelated to tumor stage, metastasis, patient survival and other clinical and pathological parameters. Our results demonstrated that Her2 overexpression occurs at relevant frequency in papillary thyroid cancer and in the absence of gene amplification. Additionally, expression of Her2 seems to hold no clinical value as prognostic factor in PTC Citation Format: Abdul K. Siraj, Shaham Beg, Rong Bu, Saif AlSobhi, Fouad Al-Dayel, Khawla Al-Kuraya. The role of Her2 overexpression in Middle Eastern papillary thyroid cancer. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 462.

PTEN loss is associated with follicular variant of Middle Eastern papillary thyroid carcinoma.

Background:PTEN gene at chromosomes 10q23.3 is a tumour suppressor gene that is inactivated in many types of human cancers. The known mechanisms of PTEN inactivation are rendered to mutation, epigenetic silencing by aberrant methylation or gene deletion. Although PTEN role has been documented in many cancers, PTEN alteration in papillary thyroid carcinoma (PTC) has not been fully elucidated. The aim of this study is to comprehensively investigate PTEN alterations in a large cohort of Middle Eastern papillary thyroid cancer by immunohistochemistry and fluorescent in situ hybridisation (FISH).Methods:PTEN protein expression was analysed by immunohistochemistry in a tissue microarray (TMA) format in a large cohort of more than 1000 patients with papillary thyroid cancer. Copy number changes in PTEN were analysed by FISH and data were correlated with clinicopathological parameters along with survival analysis.Results:PTEN inactivation reflected by complete absence of staining was seen in 24.5% of PTC samples, whereas PTEN deletion was seen only in 4.8% of the tested samples by FISH. No association was seen between PTEN loss of protein expression and PTEN gene deletion. However, interestingly, PTEN loss of expression was significantly associated with the follicular variant subset of papillary thyroid cancer.Conclusion:Our study confirmed that PTEN might have a role in pathogenesis in a subset of PTC. PTEN loss of protein expression is a more common event in follicular variant of papillary thyroid cancer. Lack of association between PTEN loss of protein expression and PTEN gene deletion might indicate that gene deletion may not be the sole cause for PTEN loss of expression and these results might raise the possibility of other mechanism such as promoter methylation-mediated gene silencing to be responsible for PTEN inactivation.

Abstract 4045: c-Met inhibition synergistically enhances death receptor-induced apoptosis via upregulation of DR5 in papillary thyroid cancer

Abstract The Met receptor tyrosine kinase and its ligand, hepatocyte growth factor (HGF), are overexpressed and/or activated in variety of human malignancies. Previously we have shown that c-Met was overexpressed in Middle Eastern Papillary Thyroid Cancer (PTC) and significantly associated with poor prognoses. In this study, we investigated the functional link between c-Met/AKT signaling pathway and Dearth Receptor 5 (DR5) in a large cohort of PTC patient samples, a panel of PTC cell lines, and xenografts in a NUDE mouse model by using tissue microarray, MTT, flow cytometry and DNA fragmentation assays and western blotting. Immunohistochemistry staining showed a significant association of p-Met with DR5 in PTC patient samples. The PHA665752, an inhibitor of c-met tyrosine kinase, inhibited cell proliferation and induced apoptosis in a dose dependent manner in all cell lines studied. PHA665752 treatment resulted in dephosphorylation of c-Met, AKT and its downstream effector molecules FOXO1, GSK-3 and pBad. Additionally, treatment of PTC cell lines with PHA665752 resulted in activation of caspases-9 and 3, cleavage PARP and apoptosis. Moreover, HGF, a ligand of c-Met, stimulated the growth of all PTC cell lines via activation of c-MET and AKT. In addition, pre-treatment of PTC cell line with PHA665752 abrogated the HGF stimulated growth and activation of c-met and AKT further suggesting the critical role of c-met and AKT pathway in PTC pathogenesis. Furthermore, c-Met inhibitor PHA665752 up-regulated DR5 expression in PTC cell line cells, and synergistically potentiated death receptor-induced apoptosis with TRAIL. Finally, co-treatment with PHA665752 and TRAIL causes more pronounced effect on PTC xenograft tumor growth in NUDE mice. Our data suggest that c-Met/HGF pathway may be a potential target for therapeutic intervention for treatment of PTC with c-Met inhibitor alone or in combination of conventionally therapeutic agents. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 4045. doi:10.1158/1538-7445.AM2011-4045

Abstract A19: Enhanced leptin receptor expression identifies an aggressive subset of Middle Eastern papillary thyroid cancer

Abstract The putative role of leptin (Ob) and its receptor (Ob-R) in the pathogenesis of various primary human malignancies has been investigated in recent studies. However, the role of leptin and leptin receptor (Ob-R) in papillary thyroid cancer (PTC) has not yet been evaluated. In this study we investigated role of Ob-R in a large tissue microarray cohort of PTC followed by in vitro studies using a panel of PTC cell lines. Ob-R overexpression was seen in 80% PTCs and was significantly associated with poor disease free survival (p=0.0235). PTCs that overexpressed Ob-R showed a aggressive phenotype characterized by older age, extrathyroid extension, larger tumor size, nodal metastasis, advanced stage and tall cell variant histological subtype (p=0.0005, p=0.0006, p=0.0398, p= 0.0004, p=0.0111 and p=0.0003 respectively). Further PTCs with overexpression of Ob-R showed a significant direct association with overexpression of leptin (p=0.0004), XIAP (p&amp;lt;0.0001) and BCL-XL (p&amp;lt;0.0001). In vitro analysis showed that leptin stimulated cell proliferation and inhibited apoptosis via activation of phosphatidylinisitol 3-kinase (PI3K)/AKT signalling pathway. Inhibition of PI3K activity by LY294002, a specific inhibitor of PI3K kinase abrogated leptin-mediated PI3K/AKT signalling. Gene silencing of Ob-R with Ob-R siRNA in PTC cells resulted in down regulation of phospho-AKT, Bcl-XL and XIAP expression suggesting that leptin mediated pathogenesis of PTC occur via involvement of these downstream targets. Altogether these data suggest that leptin plays a critical role in PTC pathogenesis through PI3K/AKT pathway via Ob-R and is a potential prognostic marker associated with an aggressive phenotype and poor disease free survival. Citation Information: Cancer Res 2009;69(23 Suppl):A19.

Clinicopathological Analysis of Papillary Thyroid Cancer withPIK3CAAlterations in a Middle Eastern Population

Genetic aberration in phosphatidylinositol 3-kinase (PI3K)/AKT pathway has been detected in numerous and diverse human cancers. PIK3CA, which encodes for the catalytic subunit of p110alpha of PI3K, is amplified in some cases of papillary thyroid cancer (PTC). Mutations in the PIK3CA have also been identified in thyroid cancers and, although relatively common in anaplastic thyroid carcinoma, are uncommon in PTC. The objective of the study was to investigate genetic alterations like PIK3CA gene mutation, PIK3CA amplification, RAS, and RAF mutations and to further explore the relationship of these genetic alterations with various clinicopathological characteristics in Middle Eastern PTC. We used the fluorescence in situ hybridization technique for analysis of PIK3CA amplification from 536 PTC cases, and selected amplified samples were further validated by real-time quantitative PCR. Mutation analysis was done by direct DNA sequencing of PIK3CA, N2-RAS, and BRAF genes. PIK3CA amplification was seen in 265 of 499 PTC cases analyzed (53.1%); PIK3CA gene mutations in four of 207 PTC (1.9%); N2-RAS mutations in 16 of 265 PTC (6%); and BRAF mutations in 153 of 296 PTC (51.7%). N-RAS mutations were-associated with an early stage (P = 0.0465) and lower incidence of extrathyroidal extension (P = 0.027), whereas BRAF mutations were-associated with metastasis (P = 0.0274) and poor disease-free survival (P = 0.0121) in PTCs. A higher incidence of PIK3CA alterations and the possible synergistic effect of PIK3CA alterations and BRAF mutations suggest their major role in Middle Eastern PTC tumorigenesis and argue for therapeutic targeting of PI3K/AKT and MAPK pathways.

Genome‐wide expression analysis of Middle Eastern papillary thyroid cancer reveals c‐MET as a novel target for cancer therapy

In an attempt to find genes that may be of importance in malignant progression of papillary thyroid carcinoma (PTC) in the Middle East, which therefore can be targeted in cancer therapy, we screened and validated the global gene expression in PTC using cDNA expression arrays and immunohistochemistry (IHC) on tumour tissue microarrays. Twenty-nine PTC tissue specimens were compared with seven non-cancerous thyroid specimens by use of cDNA microarray. Results for selected genes were confirmed by quantitative real-time PCR. Protein expression of selected genes was further studied using a tissue microarray consisting of 536 PTCs and compared with histologically non-cancerous tissue samples. One hundred and ninety-six genes were overexpressed in PTC tissues relative to non-cancerous thyroid tissues. The genes that were up-regulated in PTC were involved in cell cycle regulation, cell signaling, and oncogenesis. Among these genes, c-MET was identified by immunohistochemical methods as a protein that is overexpressed in 37% of PTCs and was significantly associated with more aggressive behaviour, eg higher stage, nodal involvement, and tall cell variant (p value = 0.01, 0.01 and 0.04, respectively). In this study, 55% of the PTC cases expressed activated AKT (P-AKT), which suggests that activated AKT may play an important role in PTC tumourigenesis. The fact that most of the PTC cases that had activated AKT showed overexpression of c-MET (p = 0.027) leads us to hypothesize that c-MET may be an alternative mechanism of AKT activation in Middle Eastern PTCs. Finally, our data suggest that c-MET dysregulation is associated with aggressive behaviour and may serve as a molecular biomarker and potential therapeutic target in this disease.