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1.
Am J Pathol ; 2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38704091

RESUMO

A number of patients with colon cancer with local or local advanced disease suffer from recurrence and there is an urgent need for better prognostic biomarkers in this setting. Here, the transcriptomic landscape of mRNAs, long noncoding RNAs, snRNAs, small nucleolar RNAs (snoRNAs), small Cajal body-specific RNAs, pseudogenes, and circular RNAs, as well as RNAs denoted as miscellaneous RNAs, was profiled by total RNA sequencing. In addition to well-known coding and noncoding RNAs, differential expression analysis also uncovered transcripts that have not been implicated previously in colon cancer, such as RNA5SP149, RNU4-2, and SNORD3A. Moreover, there was a profound global up-regulation of snRNA pseudogenes, snoRNAs, and rRNA pseudogenes in more advanced tumors. A global down-regulation of circular RNAs in tumors relative to normal tissues was observed, although only a few were expressed differentially between tumor stages. Many previously undescribed transcripts, including RNU6-620P, RNU2-20P, VTRNA1-3, and RNA5SP60, indicated strong prognostic biomarker potential in receiver operating characteristics analyses. In summary, this study unveiled numerous differentially expressed RNAs across various classes between recurrent and nonrecurrent colon cancer. Notably, there was a significant global up-regulation of snRNA pseudogenes, snoRNAs, and rRNA pseudogenes in advanced tumors. Many of these newly discovered candidates demonstrate a strong prognostic potential for stage II colon cancer.

2.
Exp Dermatol ; 30(8): 1187-1196, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33113213

RESUMO

Atopic dermatitis (AD) and psoriasis are two common chronic inflammatory skin diseases that are associated with various comorbidities. Circular RNA (circRNA) constitutes a major class of non-coding RNAs that have been implicated in many human diseases, although their potential involvement in inflammatory skin diseases remains elusive. Here, we compare and contrast the circRNA expression landscapes in paired lesional and non-lesional skin from psoriasis and AD patients relative to skin from unaffected individuals using high-depth RNA-seq data. CircRNAs and their cognate linear transcripts were quantified using the circRNA detection algorithm, CIRI2, and in situ hybridization and Sanger sequencing was used for validation purposes. We identified 39,286 circRNAs among all samples and found that psoriasis and AD lesional skin could be distinguished from non-lesional and healthy skin based on circRNA expression landscapes. In general, circRNAs were less abundant in lesional relative to non-lesional and healthy skin. Differential expression analyses revealed many significantly downregulated circRNAs, mainly in psoriasis lesional skin, and a strong correlation between psoriasis and AD-related circRNA expression changes was observed. Two individual circRNAs, ciRS-7 (also known as CDR1as) and circZRANB1, were specifically dysregulated in psoriasis and show promise as biomarkers for discriminating AD from psoriasis. In conclusion, the circRNA transcriptomes of psoriasis and AD share expression features, including a global downregulation relative to healthy skin, but this is most pronounced in psoriasis, and only psoriasis is characterized by several circRNAs being dysregulated independently of their cognate linear transcripts. Finally, specific circRNAs could potentially be used to distinguish AD from psoriasis.


Assuntos
Dermatite Atópica/genética , Psoríase/genética , RNA Circular/genética , Adulto , Dermatite Atópica/metabolismo , Regulação para Baixo , Feminino , Perfilação da Expressão Gênica , Humanos , Masculino , Pessoa de Meia-Idade , Psoríase/metabolismo , RNA Circular/metabolismo , Transcriptoma
3.
BMC Cancer ; 19(1): 142, 2019 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-30755167

RESUMO

BACKGROUND: Patients suffering from high risk stage II colon cancer (CC) may benefit from adjuvant onco-therapy, but additional prognostic markers are needed for better treatment stratification. We investigated the prognostic value of Programmed Death Ligand-1 (PD-L1) in a true population-based cohort of patients with stage II CC. METHODS: PD-L1 expression on tumour cells was evaluated by immunohistochemistry in 572 colon cancers. Whole sections from tumour blocks representing the deepest invasive front of the primary tumour were used for analysis. A cut-off of 5% positivity was used for dichotomizing the data. The prognostic value was investigated in Cox proportional hazard models for recurrence-free survival (RFS) and overall survival (OS). RESULTS: Overall, 6% of the tumours were classified as high PD-L1. High PD-L1 was related to female gender (p = 0.028), high malignancy grade (< 0.001), right side localization (p < 0.001) and microsatellite instability (MSI) (p < 0.001). Thirty-one (18%) of the MSI and 4 (1%) of the microsatellite stable tumours were classified as high PD-L1, respectively. PD-L1 expression provided no prognostic value as a single marker. In patients with MSI tumours, high PD-L1 expression had no significant impact regarding OS or RFS. CONCLUSIONS: PD-L1 expression in tumour cells of stage II CC did not provide any prognostic impact, neither in the entire population-based cohort nor in the group of MSI patients. Additional investigations of the immunogenic microenvironment are needed for evaluating the prognostic information in CC.


Assuntos
Antígeno B7-H1/metabolismo , Neoplasias do Colo/diagnóstico , Grupos Populacionais , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Neoplasias do Colo/metabolismo , Neoplasias do Colo/mortalidade , Seguimentos , Humanos , Imuno-Histoquímica , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Valor Preditivo dos Testes , Prognóstico , Análise de Sobrevida
4.
Int J Colorectal Dis ; 33(8): 1115-1124, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29785462

RESUMO

PURPOSE: High-risk patients with stage II colon cancer (CC) may benefit from adjuvant chemotherapy, but additional prognostic markers are needed for better stratification. We investigated the prognostic value of tumour stroma ratio (TSR) and tumour budding (TB). METHODS: A nationwide population-based cohort of 573 patients with stage II CC was included. TSR was scored on hematoxylin and eosin sections as low TSR (> 50% stroma) and high TSR (≤ 50% stroma). TB was evaluated in hotspots on pan-cytokeratin stained sections in 10 high power fields (HPF) at the invasive front and classified by the mean number of buds per HPF as high grade budding (≥ 10 buds) or low-grade budding (< 10 buds). The prognostic value was investigated in Cox proportional hazard models for recurrence-free survival (RFS) and overall survival (OS). RESULTS: Low TSR was associated with worse RFS (HR = 1.342 (95% CI 1.006-1.791), p = 0.045) and OS (HR = 1.376 (95% CI 1.016-1.862), p = 0.039). Furthermore, an association was found between low TSR and microsatellite stabile tumours (p < 0.001). The mean number of buds per HPF was associated to TSR with increasing number of buds related to a lower TSR (p = 0.026). No statistically significant prognostic impact of TB regarding OS or RFS was detected. CONCLUSIONS: TSR provided valuable prognostic information, and adding TSR to the current risk stratification may contribute to better patient selection. The estimates of TSR and TB were found to be associated, but no prognostic value of TB was documented.


Assuntos
Neoplasias do Colo/patologia , Estadiamento de Neoplasias , Adulto , Idoso , Criança , Pré-Escolar , Dinamarca , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia , Prognóstico , Estudos Retrospectivos
5.
Exp Mol Pathol ; 102(3): 484-491, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28512015

RESUMO

Lung cancer has the highest mortality rate amongst human cancers and the majority of deaths can be attributed to metastatic spread. The miR-34 family includes three tumor suppressive miRs: miR-34a, miR-34b and miR-34c. miR-34 downregulation is a frequent observation in human malignancies and is often attributed to hypermethylation of the miR-34a and miR-34b/c promoters. Here, the potential association between aberrant miR-34 expression and promoter methylation and distant metastases formation in lung adenocarcinoma (LAC) is investigated. The expression levels of miR-34a, miR-34b and miR-34c, as well as the methylation status of the miR-34a and miR-34b/c promoters were determined in a LAC patient cohort comprising 26 non-metastasizing and 26 metastasizing primary LACs, as well as 24 paired distant metastases and 25 tumor-adjacent normal lung samples using RT-qPCR and Methylation-Sensitive High Resolution Melting (MS-HRM) analysis. No difference in expression was observed for miR-34a when comparing metastasizing and non-metastasizing LACs (p=0.793). For both miR-34b and miR-34c, a significantly lower expression level was determined in metastasizing LACs compared to non-metastasizing LACs (p=0.0005 and p=0.002) with similarly decreased expression levels observed in the paired distant metastases. Hypermethylation was detected in 35/51 LACs compared to 0/25 tumor-adjacent normal lungs for the miR-34a promoter (p<0.0001). Similarly, 18/51 LACs compared to 1/25 tumor-adjacent normal lungs showed hypermethylation of the miR-34b/c promoter (p=0.003). No difference in methylation was observed between metastasizing and non-metastasizing LACs for neither the miR-34a (p=0.832) nor the miR-34b/c (p=0.900) promoter. In conclusion, miR-34a and miR-34b/c promoter hypermethylation is a frequent event in LAC occurring in 68.7% and 35.3% of tested cases (n=51), respectively. Low miR-34b and miR-34c expression was associated with distant metastases formation in LAC. These changes can be targeted as novel biomarkers in LAC.


Assuntos
Adenocarcinoma/genética , Regulação Neoplásica da Expressão Gênica , Neoplasias Pulmonares/genética , MicroRNAs/genética , Adenocarcinoma de Pulmão , Metilação de DNA , Humanos , MicroRNAs/metabolismo , Metástase Neoplásica/genética , Regiões Promotoras Genéticas
6.
Anal Biochem ; 468: 50-8, 2015 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-25277813

RESUMO

Formalin fixation has been the standard method for conservation of clinical specimens for decades. However, a major drawback is the high degradation of nucleic acids, which complicates its use in genome-wide analyses. Unbiased identification of biomarkers, however, requires genome-wide studies, precluding the use of the valuable archives of specimens with long-term follow-up data. Therefore, restoration protocols for DNA from formalin-fixed and paraffin-embedded (FFPE) samples have been developed, although they are cost-intensive and time-consuming. An alternative to FFPE and snap-freezing is the PAXgene Tissue System, developed for simultaneous preservation of morphology, proteins, and nucleic acids. In the current study, we compared the performance of DNA from either PAXgene or formalin-fixed tissues to snap-frozen material for genome-wide DNA methylation analysis using the Illumina 450K BeadChip. Quantitative DNA methylation analysis demonstrated that the methylation profile in PAXgene-fixed tissues showed, in comparison with restored FFPE samples, a higher concordance with the profile detected in frozen samples. We demonstrate, for the first time, that DNA from PAXgene conserved tissue performs better compared with restored FFPE DNA in genome-wide DNA methylation analysis. In addition, DNA from PAXgene tissue can be directly used on the array without prior restoration, rendering the analytical process significantly more time- and cost-effective.


Assuntos
Metilação de DNA , DNA/análise , DNA/química , Adenocarcinoma/química , Adenocarcinoma de Pulmão , Ilhas de CpG , DNA de Neoplasias/análise , DNA de Neoplasias/química , Formaldeído , Genoma Humano , Humanos , Pulmão/química , Neoplasias Pulmonares/química , Inclusão em Parafina , Reprodutibilidade dos Testes , Fixação de Tecidos
7.
Exp Mol Pathol ; 99(3): 632-40, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26551081

RESUMO

Readily accessible formalin-fixed paraffin embedded (FFPE) tissues are a highly valuable source of genetic material for molecular analyses in both research and in vitro diagnostics but frequently genetic material in those samples is highly degraded. With locus-specific methylation changes being widely investigated for use as biomarkers in various aspects of clinical disease management, we aimed to evaluate to what extent standard laboratory procedures can approximate the quality of the DNA extracted from FFPE samples prior to methylation analyses. DNA quality in 107 FFPE non-small cell lung cancer (NSCLC) samples was evaluated using spectrophotometry and gel electrophoresis. Subsequently, the quality assessment results were correlated with the results of locus specific methylation assessment with methylation sensitive high resolution melting (MS-HRM). The correlation of template quality with PCR amplification performance and HRM based methylation detection indicated a significant influence of DNA quality on PCR amplification but not on methylation assessment. In conclusion, standard laboratory procedures fairly well approximate DNA degradation of FFPE samples and DNA degradation does not seem to considerably affect locus-specific methylation assessment by MS-HRM.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/genética , Metilação de DNA/genética , DNA de Neoplasias/análise , Técnicas Genéticas , Neoplasias Pulmonares/genética , DNA de Neoplasias/metabolismo , Formaldeído , Humanos , Inclusão em Parafina , Reação em Cadeia da Polimerase , Fixação de Tecidos
8.
Exp Mol Pathol ; 99(1): 56-64, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25987486

RESUMO

Topoisomerase I (TOP1) regulates DNA topology during replication and transcription whereas tyrosyl-DNA phosphodiesterase 1 (TDP1) is involved in the repair of several types of DNA damages, including damages from defective TOP1 catalysis. TOP1 is the target of chemotherapeutic drugs of the camptothecin family (CPT). TDP1 has in cell line based assays been shown to counteract the effect of CPT. We have quantified the enzymatic activities of TOP1 and TDP1 in paired (tumor and adjacent non-tumor) samples from non-small cell lung cancer (NSCLC) patients and show that in NSCLC TOP1 and TDP1 activities are significantly upregulated in the tumor tissue. Furthermore, we found a positive correlation between the TDP1 activity and the tumor percentage (TOP1 activity did not correlate with the tumor percentage) as well as between the activities of TOP1 and TDP1 both within the tumor and the non-tumor group. That TDP1 activity was upregulated in all tumor samples and correlated with the tumor percentage suggest that it must play a highly important function in NSCLC. This could be to protect against TOP1 mediated DNA damage as the activity of TOP1 likewise was upregulated in the majority of tumor samples and correlated positively to the TDP1 activity. Regardless, the finding that the TOP1 and TDP1 activities are upregulated and correlate positively suggests that combinatorial treatment targeting both activities could be advantageous in NSCLC.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/enzimologia , DNA Topoisomerases Tipo I/metabolismo , Diester Fosfórico Hidrolases/metabolismo , Técnicas Biossensoriais , Dano ao DNA , Replicação do DNA , Humanos , Nanotecnologia , Sensibilidade e Especificidade
9.
BMC Cancer ; 14: 294, 2014 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-24773774

RESUMO

BACKGROUND: Lung cancer patients with mutations in the epidermal growth factor receptor (EGFR) are primary candidates for EGFR-targeted therapy. Reliable analyses of such mutations have previously been possible only in tumour tissue. Here, we demonstrate that mutations can be detected in plasma samples with allele-specific PCR assays. METHODS: Pairs of the diagnostic biopsy and plasma obtained just prior to start of erlotinib treatment were collected from 199 patients with adenocarcinoma of non-small-cell lung cancer. DNA from both sample types was isolated and examined for the presence of mutations in exons 18-21 of the EGFR gene, employing the cobas(®) EGFR Tissue Test and cobas(®) EGFR Blood Test (in development, Roche Molecular Systems, Inc., CA, USA). RESULTS: Test results were obtained in all 199 (100%) plasma samples and 196/199 (98%) of the biopsies. EGFR-activating mutations were identified in 24/199 (12%) plasma samples and 28/196 (14%) biopsy samples, and 17/196 (9%) matched pairs contained the same mutation. Six EGFR mutations were present only in plasma samples but not in the biopsy samples. The overall concordance of the EGFR gene mutations detected in plasma and biopsy tissue was 179/196 (91%) (kappa value: 0.621). CONCLUSION: Mutational analysis of the EGFR gene in plasma samples is feasible with allele-specific PCR assays and represents a non-invasive supplement to biopsy analysis. TRIAL REGISTRATION: M-20080012 from March 10, 2008 and reported to ClinicalTrials.gov: NCT00815971.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/sangue , Carcinoma Pulmonar de Células não Pequenas/genética , Receptores ErbB/sangue , Receptores ErbB/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Alelos , Biópsia , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/patologia , Cloridrato de Erlotinib , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , Estadiamento de Neoplasias , Quinazolinas/administração & dosagem
10.
Virchows Arch ; 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38977466

RESUMO

Tumor budding, a biomarker traditionally evaluated using hematoxylin and eosin (H&E) staining, has gained recognition as a prognostic biomarker for stage II colon cancer. Nevertheless, while H&E staining offers valuable insights, its limitations prompt the utilization of pan-cytokeratin immunohistochemistry (IHC). Consequently, this study seeks to evaluate the prognostic significance of tumor budding using IHC in a contemporary cohort of stage II colon cancer patients, aiming to deepen our understanding of this critical facet in cancer prognosis. We conducted a retrospective, population-based cohort study including 493 patients with stage II colon cancer and evaluated tumor budding using IHC, following the H&E-based guidelines proposed by the International Tumor Budding Consensus Conference Group. Correlation between H&E-based and IHC-based tumor budding was assessed using a four-tiered scoring system that included a zero budding (Bd0) category. Survival analyses explored the prognostic significance of tumor budding assessed by IHC and H&E. As expected, IHC-based tumor budding evaluation yielded significantly higher bud counts compared to H&E (p < 0.01). Interestingly, 21 patients were identified with no tumor budding using IHC. This was associated with significantly improved recurrence-free survival (HR = 5.19, p = 0.02) and overall survival (HR = 4.47, p = 0.04) in a multivariate analysis when compared to tumors with budding. The Bd0 category demonstrated a 100% predictive value for the absence of recurrence. In conclusion, IHC-based tumor budding evaluation in stage II colon cancer provides additional prognostic information. The absence of tumor budding is associated with a favorable prognosis and may serve as a potential marker for identifying patients with no risk of recurrence.

11.
Hum Pathol ; 146: 15-22, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38428823

RESUMO

Tumor budding as a prognostic marker in colorectal cancer has not previously been investigated in a cohort of screened stage II colon cancer patients. We assessed the prognostic significance of tumor budding in a thoroughly characterized stage II colon cancer population comprising surgically resected patients in the Region of Southern Denmark from 2014 to 2016. Tumors were re-staged according to the 8th edition of UICC TNM Classification, undergoing detailed histopathological evaluation and tumor budding assessment following guidelines from the International Tumor Budding Consensus Conference. Prognostic evaluation utilized Kaplan-Meier curves, log-rank tests, and Cox proportional hazard models for time to recurrence (TTR), recurrence-free survival (RFS), and overall survival (OS). Out of 497 patients, 20% were diagnosed through the national colorectal cancer screening program. High-grade tumor budding (Bd3) was found in 19% of tumors and was associated with glandular subtype, perineural invasion, mismatch repair proficient tumors, and tumor recurrence (p < 0.001, p < 0.001, p = 0.045, and p = 0.007 respectively). In multivariable Cox regression, high-grade budding was a significant prognostic factor for TTR compared to low-grade (Bd3 HR 2.617; p = 0.007). An association between tumor budding groups and RFS was observed, and the difference was significant in univariable analysis for high-grade compared to low-grade tumor budding (Bd3 HR 1.461; p = 0.041). No significant differences were observed between tumor budding groups and OS. High-grade tumor budding is a predictor of recurrence in a screened population of patients with stage II colon cancer and should be considered a high-risk factor in a shared decision-making process when stratifying patients to adjuvant chemotherapy.


Assuntos
Neoplasias do Colo , Estadiamento de Neoplasias , Humanos , Feminino , Masculino , Idoso , Neoplasias do Colo/patologia , Neoplasias do Colo/mortalidade , Pessoa de Meia-Idade , Prognóstico , Dinamarca/epidemiologia , Recidiva Local de Neoplasia/patologia , Detecção Precoce de Câncer/métodos , Idoso de 80 Anos ou mais
12.
Nat Commun ; 15(1): 2088, 2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38453924

RESUMO

Metastatic prostate cancer (PCa) poses a significant therapeutic challenge with high mortality rates. Utilizing CRISPR-Cas9 in vivo, we target five potential tumor suppressor genes (Pten, Trp53, Rb1, Stk11, and RnaseL) in the mouse prostate, reaching humane endpoint after eight weeks without metastasis. By further depleting three epigenetic factors (Kmt2c, Kmt2d, and Zbtb16), lung metastases are present in all mice. While whole genome sequencing reveals few mutations in coding sequence, RNA sequencing shows significant dysregulation, especially in a conserved genomic region at chr5qE1 regulated by KMT2C. Depleting Odam and Cabs1 in this region prevents metastasis. Notably, the gene expression signatures, resulting from our study, predict progression-free and overall survival and distinguish primary and metastatic human prostate cancer. This study emphasizes positive genetic interactions between classical tumor suppressor genes and epigenetic modulators in metastatic PCa progression, offering insights into potential treatments.


Assuntos
Sistemas CRISPR-Cas , Neoplasias da Próstata , Masculino , Humanos , Animais , Camundongos , Sistemas CRISPR-Cas/genética , Neoplasias da Próstata/genética , Neoplasias da Próstata/patologia , Transcriptoma , Família Multigênica
13.
Cancers (Basel) ; 15(18)2023 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-37760450

RESUMO

BACKGROUND: Not all patients with advanced non-small cell lung cancer (NSCLC) benefit from immune checkpoint inhibitors (ICIs). Therefore, we aimed to assess the predictive potential of gene expression profiling (GEP), peripheral immune cell counts, and clinical characteristics. METHODS: The primary endpoint of this prospective, observational study was a durable clinical benefit (DCB) defined as progression-free survival >6 months. In a subgroup with histological biopsies of sufficient quality (n = 25), GEP was performed using the nCounter® PanCancer IO 360 panel. RESULTS: DCB was observed in 49% of 123 included patients. High absolute lymphocyte count (ALC) and absence of liver metastases were associated with DCB (OR = 1.95, p = 0.038 and OR = 0.36, p = 0.046, respectively). GEP showed clustering of differentially expressed genes according to DCB, and a strong association between PD-L1 assessed by GEP (CD274) and immunohistochemistry (IHC) was observed (p = 0.00013). The TGF-ß, dendritic cell, and myeloid signature scores were higher for patients without DCB, whereas the JAK/STAT loss signature scores were higher for patients with DCB (unadjusted p-values < 0.05). CONCLUSIONS: ALC above 1.01 × 109/L and absence of liver metastases were significantly associated with DCB in ICI-treated patients with NSCLC. GEP was only feasible in 20% of the patients. GEP-derived signatures may be associated with clinical outcomes, and PD-L1 could be assessed by GEP rather than IHC.

14.
Cancer Res ; 83(20): 3340-3353, 2023 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-37477923

RESUMO

Circular RNAs (circRNA) are covalently closed molecules that can play important roles in cancer development and progression. Hundreds of differentially expressed circRNAs between tumors and adjacent normal tissues have been identified in studies using RNA sequencing or microarrays, emphasizing a strong translational potential. Most previous studies have been performed using RNA from bulk tissues and lack information on the spatial expression patterns of circRNAs. Here, we showed that the majority of differentially expressed circRNAs from bulk tissue analyses of colon tumors relative to adjacent normal tissues were surprisingly not differentially expressed when comparing cancer cells directly with normal epithelial cells. Manipulating the proliferation rates of cells grown in culture revealed that these discrepancies were explained by circRNAs accumulating to high levels in quiescent muscle cells due to their high stability; on the contrary, circRNAs were diluted to low levels in the fast-proliferating cancer cells due to their slow biogenesis rates. Thus, different subcompartments of colon tumors and adjacent normal tissues exhibited striking differences in circRNA expression patterns. Likewise, the high circRNA content in muscle cells was also a strong confounding factor in bulk analyses of circRNAs in bladder and prostate cancers. Together, these findings emphasize the limitations of using bulk tissues for studying differential circRNA expression in cancer and highlight a particular need for spatial analysis in this field of research. SIGNIFICANCE: The abundance of circRNAs varies systematically between subcompartments of solid tumors and adjacent tissues, implying that differentially expressed circRNAs discovered in bulk tissue analyses may reflect differences in cell type composition between samples.

15.
Cancer Lett ; 579: 216480, 2023 11 28.
Artigo em Inglês | MEDLINE | ID: mdl-37931834

RESUMO

Glioblastoma (GBM) is an aggressive brain tumor with a median survival of 15 months and has limited treatment options. Immunotherapy with checkpoint inhibitors has shown minimal efficacy in combating GBM, and large clinical trials have failed. New immunotherapy approaches and a deeper understanding of immune surveillance of GBM are needed to advance treatment options for this devastating disease. In this study, we used two preclinical models of GBM: orthotopically delivering either GBM stem cells or employing CRISPR-mediated tumorigenesis by adeno-associated virus, to establish immunologically proficient and non-inflamed tumors, respectively. After tumor development, the innate immune system was activated through long-term STING activation by a pharmacological agonist, which reduced tumor progression and prolonged survival. Recruitment and activation of cytotoxic T-cells were detected in the tumors, and T-cell specificity towards the cancer cells was observed. Interestingly, prolonged STING activation altered the tumor vasculature, inducing hypoxia and activation of VEGFR, as measured by a kinome array and VEGF expression. Combination treatment with anti-PD1 did not provide a synergistic effect, indicating that STING activation alone is sufficient to activate immune surveillance and hinder tumor development through vascular disruption. These results guide future studies to refine innate immune activation as a treatment approach for GBM, in combination with anti-VEGF to impede tumor progression and induce an immunological response against the tumor.


Assuntos
Neoplasias Encefálicas , Glioblastoma , Humanos , Neoplasias Encefálicas/imunologia , Neoplasias Encefálicas/metabolismo , Glioblastoma/imunologia , Glioblastoma/metabolismo , Imunoterapia/métodos , Microambiente Tumoral , Imunidade Inata
16.
Hum Mutat ; 33(1): 264-71, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21901793

RESUMO

Sensitive and specific mutation detection is of particular importance in cancer diagnostics, prognostics, and individualized patient treatment. However, the majority of molecular methodologies that have been developed with the aim of increasing the sensitivity of mutation testing have drawbacks in terms of specificity, convenience, or costs. Here, we have established a new method, Competitive Amplification of Differentially Melting Amplicons (CADMA), which allows very sensitive and specific detection of all mutation types. The principle of the method is to amplify wild-type and mutated sequences simultaneously using a three-primer system. A mutation-specific primer is designed to introduce melting temperature decreasing mutations in the resulting mutated amplicon, while a second overlapping primer is designed to amplify both wild-type and mutated sequences. When combined with a third common primer very sensitive mutation detection becomes possible, when using high-resolution melting (HRM) as detection platform. The introduction of melting temperature decreasing mutations in the mutated amplicon also allows for further mutation enrichment by fast coamplification at lower denaturation temperature PCR (COLD-PCR). For proof-of-concept, we have designed CADMA assays for clinically relevant BRAF, EGFR, KRAS, and PIK3CA mutations, which are sensitive to, between 0.025% and 0.25%, mutated alleles in a wild-type background. In conclusion, CADMA enables highly sensitive and specific mutation detection by HRM analysis.


Assuntos
Adenocarcinoma/genética , Neoplasias do Colo/genética , Análise Mutacional de DNA/métodos , DNA/genética , Mutação , Reação em Cadeia da Polimerase , Adenocarcinoma/diagnóstico , Sequência de Bases , Linhagem Celular Tumoral , Neoplasias do Colo/diagnóstico , Primers do DNA/genética , Congelamento , Genes ras , Temperatura Alta , Humanos , Dados de Sequência Molecular , Desnaturação de Ácido Nucleico , Proteínas Proto-Oncogênicas B-raf/genética , Sensibilidade e Especificidade , Temperatura de Transição
17.
BMC Cancer ; 12: 548, 2012 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-23173730

RESUMO

BACKGROUND: Cancer is an extremely heterogeneous group of diseases traditionally categorized according to tissue of origin. However, even among patients with the same cancer subtype the cellular alterations at the molecular level are often very different. Several new therapies targeting specific molecular changes found in individual patients have initiated the era of personalized therapy and significantly improved patient care. In metastatic colorectal cancer (mCRC) a selected group of patients with wild-type KRAS respond to antibodies against the epidermal growth factor receptor (EGFR). Testing for KRAS mutations is now required prior to anti-EGFR treatment, however, less sensitive methods based on conventional PCR regularly fail to detect KRAS mutations in clinical samples. METHODS: We have developed sensitive and specific assays for detection of the seven most common KRAS mutations based on a novel methodology named Competitive Amplification of Differentially Melting Amplicons (CADMA). The clinical applicability of these assays was assessed by analyzing 100 colorectal cancer samples, for which KRAS mutation status has been evaluated by the commercially available TheraScreen® KRAS mutation kit. RESULTS: The CADMA assays were sensitive to at least 0.5% mutant alleles in a wild-type background when using 50 nanograms of DNA in the reactions. Consensus between CADMA and the TheraScreen kit was observed in 96% of the colorectal cancer samples. In cases where disagreement was observed the CADMA result could be confirmed by a previously published assay based on TaqMan probes and by fast COLD-PCR followed by Sanger sequencing. CONCLUSIONS: The high analytical sensitivity and specificity of CADMA may increase diagnostic sensitivity and specificity of KRAS mutation testing in mCRC patients.


Assuntos
Neoplasias Colorretais/genética , Análise Mutacional de DNA/métodos , Mutação , Proteínas Proto-Oncogênicas/genética , Proteínas ras/genética , Linhagem Celular Tumoral , Neoplasias Colorretais/patologia , DNA de Neoplasias/química , DNA de Neoplasias/genética , Humanos , Reação em Cadeia da Polimerase , Proteínas Proto-Oncogênicas p21(ras) , Reprodutibilidade dos Testes , Análise de Sequência de DNA
18.
Nat Rev Clin Oncol ; 19(3): 188-206, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34912049

RESUMO

Over the past decade, circular RNAs (circRNAs) have emerged as a large class of primarily non-coding RNA molecules, many of which have key roles in cancer development and progression through diverse mechanisms of action. CircRNAs often have tissue-restricted and cancer-specific expression patterns, and accumulating data suggest that these molecules are of potential clinical relevance and utility. In particular, circRNAs have strong potential as diagnostic, prognostic and predictive biomarkers, which is underscored by their detectability in liquid biopsy samples such as in plasma, saliva and urine. However, technical issues in the detection and assessment of circRNAs as well as biological knowledge gaps need to be addressed to move this relatively young field of research forward and bring circRNAs to the forefront of clinical practice. Herein, we review the current knowledge regarding circRNA biogenesis, regulation and functions in cancer as well as their clinical potential as biomarkers, therapeutic agents and drug targets.


Assuntos
Neoplasias , RNA Circular , Biomarcadores , Humanos , Biópsia Líquida , Oncologia , Neoplasias/terapia , RNA Circular/genética
19.
Sci Rep ; 12(1): 7318, 2022 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-35513459

RESUMO

The primary treatment of the common malignancy squamous cell carcinoma is surgical removal. In this process, sufficient tissue removal is balanced against unnecessary mutilation. We recently presented a remote photoplethysmography algorithm, which revealed significant differences between processed video recordings of cancer biopsy areas and surrounding tissue. The aim of this study was to investigate whether spatial analyses of photoplethysmography data correlate with post-excision pathological analyses and thus have potential to assist in tumour delineation. Based on high speed video recordings of 11 patients with squamous cell carcinoma, we examined different parameters derived from temporal remote photoplethysmography variations. Signal characteristics values in sites matching histological sections were compared with pathological measures. Values were ranked and statistically tested with a Kendall correlation analysis. A moderate, negative correlation was found between signal oscillations and the width and transversal area of squamous cell carcinoma in the frequencies below 1 Hz and specifically from 0.02 to 0.15 Hz. We have presented a correlation between frequency content and prevalence of cancer based on regular video recordings of squamous cell carcinoma. We believe this is supported by published findings on malignant melanoma. Our findings indicate that photoplethysmography can be used to distinguish SCC from healthy skin.


Assuntos
Carcinoma de Células Escamosas , Melanoma , Neoplasias Cutâneas , Carcinoma de Células Escamosas/patologia , Humanos , Fotopletismografia , Neoplasias Cutâneas/patologia , Análise Espacial
20.
PLoS One ; 17(9): e0275219, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36174034

RESUMO

Psoriasis is a common chronic inflammatory skin disease accompanied by heterogenous clinical and histological features, including a characteristic keratinocyte hyperproliferation and dermal immunogenic profile. In addition, psoriasis is associated with widespread transcriptomic alterations including changes in microRNA (miRNA) and circular RNA (circRNA) abundance, which constitute non-coding RNA (ncRNA) classes with specific regulatory capacities in diverse physiological and pathological processes. However, the knowledge about the expression dynamics of ncRNA during psoriasis treatment is sparse. To elucidate the dynamics of miRNA and circRNA abundance during secukinumab (anti-IL-17A) treatment, we studied their expression patterns in skin biopsies from 14 patients with severe plaque-type psoriasis before and during an 84-day secukinumab therapy at day 0, 4, 14, 42, and 84 using NanoString nCounter technology. We found a comprehensive downregulation of the majority of investigated circRNAs and specific alterations in the miRNA profile, including an upregulation of miR-203a-3p, miR-93-5p, and miR-378i in lesional compared to non-lesional skin before treatment. During treatment, the circRNAs progressively returned to the expression levels observed in non-lesional skin and already four days after treatment initiation most circRNAs were significantly upregulated. In comparison, for miRNAs, the normalization to baseline during treatment was delayed and limited to a subset of miRNAs. Moreover, we observed a strong correlation between multiple circRNAs, including ciRS-7 and circPTPRA, and the psoriasis area and severity index (PASI). Similar pronounced correlations could, however, not be found for miRNAs. Finally, we did not observe any significant changes in circRNA expression in peripheral blood mononuclear cells during treatment. In conclusion, we uncovered a rapid shift in global circRNA abundance upon anti-IL-17A treatment, which predated clinical and histological improvements, and a strong correlation with PASI, indicating a biomarker potential of individual circRNAs.


Assuntos
MicroRNAs , Psoríase , RNA Circular , Anticorpos Monoclonais Humanizados , Humanos , Leucócitos Mononucleares , MicroRNAs/genética , Psoríase/tratamento farmacológico , Psoríase/genética , RNA Circular/genética
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