Genetic alterations landscape in paediatric thyroid tumours and/or differentiated thyroid cancer: Systematic review.

Differentiated thyroid cancer (DTC) is a rare disease in the paediatric population (≤ 18 years old. at diagnosis). Increasing incidence is reflected by increases in incidence for papillary thyroid carcinoma (PTC) subtypes. Compared to those of adults, despite aggressive presentation, paediatric DTC has an excellent prognosis. As for adult DTC, European and American guidelines recommend individualised management, based on the differences in clinical presentation and genetic findings. Therefore, we conducted a systematic review to identify the epidemiological landscape of all genetic alterations so far investigated in paediatric populations at diagnosis affected by thyroid tumours and/or DTC that have improved and/or informed preventive and/or curative diagnostic and prognostic clinical conduct globally. Fusions involving the gene RET followed by NTRK, ALK and BRAF, were the most prevalent rearrangements found in paediatric PTC. BRAF V600E was found at lower prevalence in paediatric (especially ≤ 10 years old) than in adults PTC. We identified TERT and RAS mutations at very low prevalence in most countries. DICER1 SNVs, while found at higher prevalence in few countries, they were found in both benign and DTC. Although the precise role of DICER1 is not fully understood, it has been hypothesised that additional genetic alterations, similar to that observed for RAS gene, might be required for the malignant transformation of these nodules. Regarding aggressiveness, fusion oncogenes may have a higher growth impact compared with BRAF V600E. We reported the shortcomings of the systematized research and outlined three key recommendations for global authors to improve and inform precision health approaches, glocally.

TERT and BRAF V600E mutations in thyroid cancer of World Trade Center Responders.

The 2-fold excess thyroid cancer risk reported in multiple World Trade Center (WTC) disaster exposed cohorts cannot entirely be explained by surveillance and physician bias thus highlighting the need to investigate the potential consequences of the dust exposure, containing carcinogenic and endocrine disruptive elements, on the thyroid. This study investigated the presence of TERT promoter and BRAF V600E mutations in 20 WTC-exposed versus 23 matched non-exposed thyroid cancers as potential mechanism explaining the excess risk. Although no significant difference in BRAF V600E mutation was found, TERT promoter mutations were significantly more prevalent in WTC thyroid cancer versus non-exposed thyroid cancers (P = 0.021). The odds of a TERT promoter mutation was significantly higher in the WTC versus the non-WTC thyroid cancers after adjustment [ORadj: 7.11 (95% CI: 1.21-41.83)]. These results may indicate that exposure to the mixture of pollutants present in the WTC dust resulted in an excess thyroid cancer risk and potentially more aggressive thyroid cancer, warranting investigating WTC responders on thyroid-associated symptoms during their health checkups. Future studies should include long-term follow-up to provide important insights in whether thyroid-specific survival is negatively affected by WTC dust exposure and whether this is because of the presence of one or more driver mutations.

AGK-BRAF is associated with distant metastasis and younger age in pediatric papillary thyroid carcinoma.

BACKGROUND: The incidence of thyroid carcinoma has increased in most populations, including pediatric patients. The increase is almost exclusively due to an increase in the incidence of papillary thyroid carcinoma (PTC). Genetic alterations leading to mitogen-activated protein kinase (MAPK) pathway activation are highly prevalent in PTC, with BRAF V600E mutation being the most common event in adult PTC. Although a lower prevalence of BRAF V600E had been reported among pediatric patients, a higher prevalence of BRAF fusion has been identified in both radiation-exposed and sporadic pediatric PTC. However, little is known about the prognostic implications of BRAF fusions in pediatric PTC. PROCEDURE: In this study, we investigated the prevalence of BRAF alterations (AGK-BRAF fusion and BRAF V600E mutation) in a large set of predominantly sporadic pediatric PTC cases and correlate with clinicopathological features. Somatic AGK-BRAF fusion was investigated by RT-PCR and confirmed by FISH break-apart. The BRAF V600E mutation was screened using Sanger sequencing. RESULTS: AGK-BRAF fusion, found in 19% of pediatric PTC patients, was associated with distant metastasis and younger age. Conversely, the BRAF V600E, found in 15% of pediatric PTC patients, was correlated with older age and larger tumor size. CONCLUSION: Collectively, our results advance knowledge concerning genetic bases of pediatric thyroid carcinoma, with potential implications for diagnosis, prognosis, and therapeutic approaches.

Analysis of KIAA1549-BRAF fusion gene expression and IDH1/IDH2 mutations in low grade pediatric astrocytomas.

Low-grade astrocytomas comprise about 30 % of the central nervous system tumors in children. Several investigations have searched a correlation between the BRAF gene fusions alterations and mutations at IDH1 and IDH2 genes in low grade pediatric astrocytomas. This study identified the expression of KIAA1549-BRAF fusion gene and BRAF V600E mutation, mutations at exon 4 of the IDH1 and IDH2 genes in samples of pilocytic astrocytomas (PA) and grade-II astrocytomas (A-II) pediatric patients. The correlation between these alterations and the clinical profile of the patients was also evaluated. Eighty-two samples of low-grade astrocytomas (65 PA and 17 A-II) were analyzed by PCR and sequencing for each of the targets identified. We identified the KIAA1549-BRAF fusion transcript in 45 % of the samples. BRAF V600E and BRAFins598T mutations were detected in 7 and 1 % of the samples, respectively. Mutations in the R132/R172 residues of the IDH1/IDH2 genes were detected in only two samples, and the G105G polymorphism (rs11554137:C>T) was identified in ten patients. Additionally, we observed two mutations out of the usual hotspots at IDH1 and IDH2 genes. We observed a smaller frequency of mutations in IDHs genes than previously described, but since the prior studies were composed of adult or mixed (adults and children) samples, we believe that our results represent a relevant contribution to the growing knowledge in low grade childhood astrocytomas.

DARC (Duffy) and BCAM (Lutheran) reduced expression in thyroid cancer.

Duffy or DARC (Duffy Antigen Receptor for Chemokines) is a glycosylated membrane protein that selectively binds angiogenic chemokines. Previous in vivo and in vitro studies of DARC function in cancer have associated DARC over expression with better prognosis, decreased metastatic potential, and inhibition of tumor-associated neovascularization. Another carcinogenesis-associated antigen is Lutheran or BCAM (basal cell adhesion molecule), a surface glycoprotein that acts as a receptor for the extracellular matrix protein, laminin. BCAM is a protein related to tumor progression; and, its over expression is associated with skin, ovarian and pancreatic cancers. We explored DARC and BCAM functions and investigated whether or not their expressions were altered in thyroid cancer. The expression of DARC and BCAM were evaluated by quantitative real-time PCR (qPCR) in a set of 18 normal thyroid tissues (NT), 15 follicular adenomas (FTA), 17 follicular carcinomas (FTC), and 122 papillary thyroid carcinomas (PTC), including 78 classical (CVPTC) and 44 follicular variant (FVPTC). RNA was isolated, reverse transcribed to cDNA, and used in qPCR reactions containing SYBR Green. The relative expression value was calculated using ribosomal protein S8 as an internal control. When we compared benign (NT and FTA) versus malignant samples (FTC, CVPTC and FVPTC) we observed a significant decrease of DARC and BCAM relative expression in malignant cases. Additionally, we correlated clinic-pathological features (tumor size, presence of metastasis, presence of lymphocyte infiltrate) with DARC and BCAM expression. We found a diminished expression of DARC in PTC samples, which was correlated with tumor size and presence of a lymphocyte infiltrate. We, also, found a correlation between decreased BCAM expression and tumor size or presence of metastasis. DARC and BCAM expression was associated with pathogenesis of thyroid carcinoma and correlated with clinical-pathological features.

Correlation of MLH1 and MGMT expression and promoter methylation with genomic instability in patients with thyroid carcinoma.

BACKGROUND: Gene silencing of the repair genes MLH1 and MGMT was shown to be a mechanism underlying the development of microsatellite instability (MSI), a phenotype frequently associated with various human malignancies. Recently, aberrant methylation of MLH1, MGMT and MSI were shown to be associated with mutations in genes such as BRAF, RAS and IDH1 in colon and brain tumours. Little is known about the methylation status of MLH1 and MGMT in thyroid tumours and its association with MSI and mutational status. METHODS: In a series of 96 thyroid tumours whose mutational profiles of BRAF, IDH1 and NRAS mutations and RET/PTC were previously determined, we investigated MLH1 and MGMT expression and methylation status by qPCR and methylation-specific PCR after bisulphite treatment, respectively. MSI was determined by PCR using seven standard microsatellite markers. RESULTS: Samples with point mutations (BRAF, IDH1 and NRAS) show a decrease in MLH1 expression when compared to negative samples. Additionally, malignant lesions show a higher MSI pattern than benign lesions. The MSI phenotype was also associated with down-regulation of MLH1. CONCLUSIONS: The results of this study allow us to conclude that low expression of MLH1 is associated with BRAF V600E mutations, RET/PTC rearrangements and transitions (IDH1 and NRAS) in patients with thyroid carcinoma. In addition, a significant relationship between MSI status and histological subtypes was found.

Identification of NID1 as a novel candidate susceptibility gene for familial non-medullary thyroid carcinoma using whole-exome sequencing.

The genetics underlying non-syndromic familial non-medullary thyroid carcinoma (FNMTC) is still poorly understood. To identify susceptibility genes for FNMTC, we performed whole-exome sequencing (WES) in a Brazilian family affected by papillary thyroid carcinoma (PTC) in three consecutive generations. WES was performed in four affected and two unaffected family members. Manual inspection in over 100 previously reported susceptibility genes for FNMTC showed that no variants in known genes co-segregated with disease phenotype in this family. Novel candidate genes were investigated using PhenoDB and filtered using Genome Aggregation (gnomAD) and Online Archive of Brazilian Mutations (ABraOM) population databases. The missense variant p.Ile657Met in the NID1 gene was the only variant that co-segregated with the disease, while absent in unaffected family members and controls. The allele frequency for this variant was <0.0001 in the gnomAD and ABbraOM databases. In silico analysis predicted the variant to be deleterious or likely damaging to the protein function. Somatic mutations in NID1 gene were found in nearly 500 cases of different cancer subtypes in the intOGen platform. Immunohistochemistry analysis showed NID1 expression in PTC cells, while it was absent in normal thyroid tissue. Our findings were corroborated using data from the TCGA cohort. Moreover, higher expression of NID1 was associated with higher likelihood of relapse after treatment and N1b disease in PTCs from the TCGA cohort. Although replication studies are needed to better understand the role of this variant in the FNMTC susceptibility, the NID1 variant (c.1971T>G) identified in this study fulfills several criteria that suggest it as a new FNMTC predisposing gene.

Membrane estrogen receptor ERα activation improves tau clearance via autophagy induction in a tauopathy cell model.

Alzheimer's disease (AD) is the most prevalent aging-associated neurodegenerative disease, with a higher incidence in women than men. There is evidence that sex hormone replacement therapy, particularly estrogen, reduces memory loss in menopausal women. Neurofibrillary tangles are associated with tau protein aggregation, a characteristic of AD and other tauopathies. In this sense, autophagy is a promising cellular process to remove these protein aggregates. This study evaluated the autophagy mechanisms involved in neuroprotection induced by 17ß-estradiol (E2) in a Tet-On inducible expression tauopathy cell model (EGFP-tau WT or with the P301L mutation, 0N4R isoform). The results indicated that 17ß-estradiol induces autophagy by activating AMPK in a concentration-dependent manner, independent of mTOR signals. The estrogen receptor α (ERα) agonist, PPT, also induced autophagy, while the ERα antagonist, MPP, substantially attenuated the 17ß-estradiol-mediated autophagy induction. Notably, 17ß-estradiol increased LC3-II levels and phosphorylated and total tau protein clearance in the EGFP-tau WT cell line but not in EGPF-tau P301L. Similar results were observed with E2-BSA, a plasma membrane-impermeable estrogen, suggesting membrane ERα involvement in non-genomic estrogenic pathway activation. Furthermore, 17ß-estradiol-induced autophagy led to EGFP-tau protein clearance. These results demonstrate that modulating autophagy via the estrogenic pathway may represent a new therapeutic target for treating AD.

Comprehensive Assessment of Copy Number Alterations Uncovers Recurrent AIFM3 and DLK1 Copy Gain in Medullary Thyroid Carcinoma.

Medullary thyroid carcinoma (MTC) is a malignant tumor originating from thyroid C-cells that can occur either in sporadic (70-80%) or hereditary (20-30%) form. In this study we aimed to identify recurrent copy number alterations (CNA) that might be related to the pathogenesis or progression of MTC. We used Affymetrix SNP array 6.0 on MTC and paired-blood samples to identify CNA using PennCNV and Genotyping Console software. The algorithms identified recurrent copy number gains in chromosomes 15q, 10q, 14q and 22q in MTC, whereas 4q cumulated losses. Coding genes were identified within CNA regions. The quantitative PCR analysis performed in an independent series of MTCs (n = 51) confirmed focal recurrent copy number gains encompassing the DLK1 (14q32.2) and AIFM3 (22q11.21) genes. Immunohistochemistry confirmed AIFM3 and DLK1 expression in MTC cases, while no expression was found in normal thyroid tissues and few MTC samples were found with normal copy numbers. The functional relevance of CNA was also assessed by in silico analysis. CNA status correlated with protein expression (DLK1, p = 0.01), tumor size (DLK1, p = 0.04) and AJCC staging (AIFM3p = 0.01 and DLK1p = 0.05). These data provide a novel insight into MTC biology, and suggest a common CNA landscape, regardless of if it is sporadic or hereditary MTC.

Advances in Detecting Low Prevalence Somatic TERT Promoter Mutations in Papillary Thyroid Carcinoma.

Background: Two recurrent TERT (telomerase reverse transcriptase) promoter mutations, C228T and C250T, have been reported in thyroid carcinomas and were correlated with high-risk clinicopathological features and a worse prognosis. Although far more frequent in the poorly differentiated and undifferentiated thyroid cancer, the TERT promoter mutations play a significant role on PTC recurrence and disease-specific mortality. However, the prevalence varies considerably through studies and it is uncertain if these differences are due to population variation or the methodology used to detect TERT mutations. In this study we aim to compare three different strategies to detect TERT promoter mutations in PTC. Methods: DNA was isolated from formalin-fixed paraffin-embedded (FFPE) specimens from 89 PTC and 40 paired lymph node metastases. The prevalence of the hot spot TERT C228T and C250T mutations was assessed in FFPE samples using TaqMan SNP genotyping assays. Random samples were tested by Sanger Sequencing and droplet digital PCR (ddPCR). Results: In general, 16 out of 89 (18%) PTC samples and 14 out of 40 (35%) lymph node metastases harbored TERT promoter mutations by TaqMan assay. Sanger sequencing, performed in random selected samples, failed to detect TERT mutations in four samples that were positive by TaqMan SNP genotyping assay. Remarkably, ddPCR assay allowed detection of TERT promoter mutations in six samples that harbor very low mutant allele frequency (≤ 2%) and were negative by both genotype assay and Sanger Sequencing. Conclusion: This study observed a good concordance among the methodologies used to detect TERT promoter mutations when a high percentage of mutated alleles was present. Sanger analysis demonstrated a limit of detection for mutated alleles. Therefore, the prevalence of TERT promoter mutations in PTC may be higher than previously reported, since most studies have conventionally used Sanger sequencing. The efficient characterization of genetic alterations that are used as preoperative or postoperative diagnostic, risk stratification of the patient and individualized treatment decisions, mainly in highly heterogeneous tumors, require highly sensitive and specific approaches.

Evidence of Cooperation between Hippo Pathway and RAS Mutation in Thyroid Carcinomas.

Thyroid cancer incidences have been steadily increasing worldwide and are projected to become the fourth leading cancer diagnosis by 2030. Improved diagnosis and prognosis predictions for this type of cancer depend on understanding its genetic bases and disease biology. RAS mutations have been found in a wide range of thyroid tumors, from benign to aggressive thyroid carcinomas. Based on that and in vivo studies, it has been suggested that RAS cooperates with other driver mutations to induce tumorigenesis. This study aims to identify genetic alterations or pathways that cooperate with the RAS mutation in the pathogenesis of thyroid cancer. From a cohort of 120 thyroid carcinomas, 11 RAS-mutated samples were identified. The samples were subjected to RNA-Sequencing analyses. The mutation analysis in our eleven RAS-positive cases uncovered that four genes that belong to the Hippo pathway were mutated. The gene expression analysis revealed that this pathway was dysregulated in the RAS-positive samples. We additionally explored the mutational status and expression profiling of 60 RAS-positive papillary thyroid carcinomas (PTC) from The Cancer Genome Atlas (TCGA) cohort. Altogether, the mutational landscape and pathway enrichment analysis (gene set enrichment analysis (GSEA) and Kyoto Encyclopedia of Genes and Genome (KEGG)) detected the Hippo pathway as dysregulated in RAS-positive thyroid carcinomas. Finally, we suggest a crosstalk between the Hippo and other signaling pathways, such as Wnt and BMP.

Molecular Signature Expands the Landscape of Driver Negative Thyroid Cancers.

Thyroid cancer is the most common endocrine malignancy. However, the cytological diagnosis of follicular thyroid carcinoma (FTC), Hürthle cell carcinoma (HCC), and follicular variant of papillary thyroid carcinoma (FVPTC) and their benign counterparts is a challenge for preoperative diagnosis. Nearly 20-30% of biopsied thyroid nodules are classified as having indeterminate risk of malignancy and incur costs to the health care system. Based on that, 120 patients were screened for the main driver mutations previously described in thyroid cancer. Subsequently, 14 mutation-negative cases that are the main source of diagnostic errors (FTC, HCC, or FVPTC) underwent RNA-Sequencing analysis. Somatic variants in candidate driver genes (ECD, NUP98,LRP1B, NCOR1, ATM, SOS1, and SPOP) and fusions were described. NCOR1 and SPOP variants underwent validation. Moreover, expression profiling of driver-negative samples was compared to 16 BRAF V600E, RAS, or PAX8-PPARg positive samples. Negative samples were separated in two clusters, following the expression pattern of the RAS/PAX8-PPARg or BRAF V600E positive samples. Both negative groups showed distinct BRS, ERK, and TDS scores, tumor mutation burden, signaling pathways and immune cell profile. Altogether, here we report novel gene variants and describe cancer-related pathways that might impact preoperative diagnosis and provide insights into thyroid tumor biology.

LIMD2 Regulates Key Steps of Metastasis Cascade in Papillary Thyroid Cancer Cells via MAPK Crosstalk.

Although papillary thyroid carcinoma (PTC) has a good prognosis, 20-90% of patients show metastasis to regional lymph nodes and 10-15% of patients show metastasis to distant sites. Metastatic disease represents the main clinical challenge that impacts survival rate. We previously showed that LIMD2 was a novel metastasis-associated gene. In this study, to interrogate the role of LIMD2 in cancer invasion and metastasis, we used CRISPR-mediated knockout (KO) of LIMD2 in PTC cells (BCPAP and TPC1). Western blot and high-content screening (HCS) analysis confirmed functional KO of LIMD2. LIMD2 KO reduced in vitro invasion and migration. Ultrastructural analyses showed that cell polarity and mitochondria function and morphology were restored in LIMD2 KO cells. To unveil the signals supervising these phenotypic changes, we employed phospho-protein array. Several members of the MAPK superfamily showed robust reduction in phosphorylation. A Venn diagram displayed the overlap of kinases with reduced phosphorylation in both cell lines and showed that they were able to initiate or sustain the epithelial-mesenchymal transition (EMT) and DNA damage checkpoint. Flow cytometry and HCS validation analyses further corroborated the phospho-protein array data. Collectively, our findings show that LIMD2 enhances phosphorylation of kinases associated with EMT and invasion. Through cooperation with different kinases, it contributes to the increased genomic instability that ultimately promotes PTC progression.

FAM129A regulates autophagy in thyroid carcinomas in an oncogene-dependent manner.

We previously proposed that high expression of FAM129A can be used as a thyroid carcinoma biomarker in preoperative diagnostic exams of thyroid nodules. Here, we identify that FAM129A expression is increased under nutrient and growth factor depletion in a normal thyroid cell line (PCCL3), overlapping with increased expression of autophagy-related protein and inhibition of AKT/mTOR/p70S6K. Supplementation of insulin, TSH and serum to the medium was able to reduce the expression of both FAM129A and autophagy-related protein and reestablish the AKT/mTOR/p70S6K axis. To determine the direct role of FAM129A on autophagy, FAM129A was transfected into PCCL3 cells. Its overexpression induced autophagic vesicles formation, evidenced by transmission electron microscopy. Co-expression of FAM129A and mCherry-EGFP-LC3B in PCCL3 showed an increased yellow puncta formation, suggesting that FAM129Ainduces autophagy. To further confirm its role on autophagy, we knockdown FAM129A in two thyroid carcinoma cell lines (TPC1 and FTC-236). Unexpectedly, FAM129A silencing increased autophagic flux, suggesting that FAM129A inhibits autophagy in these models. We next co-transfected PCCL3 cells with FAM129A and RET/PTC1 and tested autophagy in this context. Co-expression of FAM129A and RET/PTC1 oncogene in PCCL3 cells, inhibited RET/PTC1-induced autophagy. Together, our data suggest that, in normal cells FAM129A induces autophagy in order to maintain cell homeostasis and provide substrates under starvation conditions. Instead, in cancer cells, decreased autophagy may help the cells to overcome cell death. FAM129A regulates autophagy in a cell- and/or context-dependent manner. Our data reinforce the concept that autophagy can be used as a strategy for cancer treatment.

Revised criteria for diagnosis of NIFTP reveals a better correlation with tumor biological behavior.

The recent reclassification of a follicular variant of papillary thyroid carcinoma (FVPTC), subset as noninvasive follicular thyroid neoplasm with papillary-like nuclear features (NIFTP), aims to avoid overtreatment of patients with an indolent lesion. The diagnosis of NIFTP has recently been revisited using more rigid criteria. This study presents histological and molecular findings and a long clinical follow-up of 94 FVPTC, 40 cases of follicular adenoma (FTA) and 22 cases of follicular carcinoma (FTC) that were classified before the advent of the NIFTP reclassification. All slides were reviewed using these rigid criteria and analysis of numerous sections of paraffin blocks and reclassified as 7 NIFTPs, 2 EFVPTCs, 29 infiltrative FVPTC (IFVPTCs), 57 invasive EFVPTC (I-EFVPTCs), 39 FTAs and 22 FTCs. Remarkably, EFVPTC and NIFTP patients were all free of disease at the end of follow-up and showed no BRAF mutation. Only one NIFTP sample harbored mutations, an NRAS Q61R. PAX8/PPARG fusion was found in I-EFVPTCs and FTC. Although additional studies are needed to identify a specific molecular profile to aid in the diagnosis of lesions with borderline morphological characteristics, we confirmed that the BRAF V600E mutation is an important tool to exclude the diagnosis of NIFTP. We also show that rigorous histopathological criteria should be strongly followed to avoid missing lesions in which more aggressive behavior is present, mainly via the analysis of capsule or vascular invasion and the presence of papillary structures.

ETV6-NTRK3 and STRN-ALK kinase fusions are recurrent events in papillary thyroid cancer of adult population.

OBJECTIVE: PTC-specific analysis identified novel fusions involving RET, BRAF, NTRK1, NTRK3, AGK and ALK genes in adults and pediatric PTCs. Although many novel fusions are PTC-specific events and, therefore, are ideal for diagnosis purposes, validation across additional and larger patient cohorts is essential for introducing these potential diagnostic or prognostic biomarkers into the clinical practice. As most of the BRAF, NTRK3 and ALK fusions were initially found in pediatric PTC or in more aggressive thyroid carcinomas, and there is a great disparity across population, in this study, we screened a large set of adult-sporadic PTC cases for the most prevalent kinase fusion lately described in the TCGA. DESIGN AND METHODS: The prevalence of the fusions was determined by RT-PCR in 71 classical PTC, 45 follicular variants of PTC (FVPTC), 19 follicular thyroid adenomas (FTAs) and 22 follicular thyroid carcinomas (FTCs). RESULTS: ETV6-NTRK3 was exclusively found in FVPTC, in both encapsulated and infiltrative variants, but was not found in FTAs and FTCs. STRN-ALK was found in both classical PTC and FVPTC. No AGK-BRAF fusion was identified in this series, endorsing that AGK-BRAF is a genetic event mainly associated with pediatric PTCs. CONCLUSIONS: The identification of kinase fusions in thyroid carcinomas helps to expand our knowledge about the landscape of oncogenic alterations in PTC. As ETV6-NTRK3 and STRN-ALK are recurrent and not identified in benign lesions, they can certainly help with diagnosis of thyroid nodules. Further analysis is needed to define if they can also be useful for prognosis and guiding therapy.

The human papillomavirus (HPV)-related cancer biology: An overview.

Despite the novel diagnostic methods and therapies implemented in oncology, the number of patients that succumb by the cancer remains high globally. Currently studies point out that 20-25% of all human malignancies are related to micro-organism infections. Among these cancer-related pathogens, the human papillomavirus (HPV) has a prominent position, since the virus is responsible for about 30% of all infectious agent-related cancers. Thus, an amount of cancers could be avoided by means prophylactic and/or therapeutic measures. However, these measures required a holistic comprehension about HPV-related cancer biology. Based on this, this review aims to summarize the last evidences of HPV on cancer biology (from initiation to metastasis), focus on molecular and biochemical deregulations associated with viral infection, and discuss the viral etiology in different malignancies.

Flavones-bound in benzodiazepine site on GABAA receptor: Concomitant anxiolytic-like and cognitive-enhancing effects produced by Isovitexin and 6-C-glycoside-Diosmetin.

Increasing evidence suggests that flavones can modulate memory and anxiety-like behaviour. However, these therapeutic effects are inconsistent and induce of adverse effects, which have been associated with interactions at the Benzodiazepine (BZ)-binding site. To improve our understanding of flavone effects on memory and anxiety, we employed a plus-maze discriminative avoidance task. Furthermore, we evaluated the potential of the compounds in modulating GABAA receptors via BZ-binding site using molecular modelling studies. Adult male Wistar rats were treated 30 min before training session with Vicenin-2 (0.1 and 0.25 mg/kg), Vitexin (0.1 and 0.25 mg/kg), Isovitexin (0.1 and 0.25 mg/kg) and 0.1 mg/kg 6-C-glycoside-Diosmetin, vehicle and a GABAA receptor agonist. The analysis of the time spent in the non-aversive vs aversive enclosed arms during the test session and percentage of time in the open arms within the training session revealed that treatment with Isovitexin and 6-C-glycoside-Diosmetin had memory-enhancing and anxiolytic-like effects (P < 0.001). In contrast, treatment with a higher dose of Diazepam impaired short-and long-term memory when it alleviated anxiety level. Docking studies revealed that flavones docked in a very similar way to that observed to the Diazepam, except by a lack of interaction in residue α1His101 in the BZ-binding site on GABAA receptors, which may be related to memory-enhancing effect. The occurrence of the α1His101 interaction could justify the memory-impairing observed following Diazepam treatment. These findings provide the first evidence that Isovitexin and 6-C-glycoside-Diosmetin could exert their memory-enhancing and anxiolytic-like effects via GABAA receptor modulation, which likely occurs via their benzodiazepine-binding site.