Gene fusions provide access to new therapeutic opportunities for patients treated for a colorectal cancer (CRC). However, they do not excess 1% of patients. A better identification of patients in ...whom gene fusions are highly prevalent is a major issue in a therapeutic and medico-economics perspective. This study assesses the rates of gene fusions in CRC patients with MSI/RAS-BRAFWT in our routine practice detected with a commercially available NGS-based fusion panel. Among the 130 MSI CRC tumors, 43 (33%) were KRAS-NRAS-BRAFWT. A gene fusion was detected in 7 (25.9%) of the 27 MSI/RAS-BRAFWT samples, which had RNA suitable for analysis after quality control. These fusions involved mainly NTRK1/3 (n = 5), as well as ALK (n = 1) and BRAF (n = 1). In the present study, we confirm that patients with MSI/RAS-BRAFWT CRCs represent a subpopulation in which targetable gene fusions are overrepresented. Our results support the use of a two-step algorithm for molecular screening, in which metastatic CRC patients would have routine MSI and RAS/BRAF testing, and then only those with MSI/RAS-BRAFWT would be screened with dedicated NGS RNA panel for gene fusions.
•Gene fusions do not excess 1% of patients with colorectal cancer (CRC).•Gene fusions are overrepresented in patients with MSI/RAS-BRAFWT CRC.•Most of gene fusions provide access to new therapeutic opportunities.•Our results support the use of a two-step algorithm for molecular screening.
Abstract Objectives Immunotherapy for bladder cancer seems to have promising results. Here, we evaluated the association between messenger RNA (mRNA) and protein levels and possible prognostic value ...of the programmed cell death 1/programmed cell death ligand 1 (PD-1/PD-L1) and cytotoxic T-lymphocyte-associated protein 4 (CTLA4) immune checkpoint pathways during bladder carcinogenesis. Methods and materials Tumor samples were obtained from 155 patients (84 with muscle-invasive bladder cancer MIBC, and 71 non–muscle-invasive bladder cancer NMIBC) and normal bladder tissue from 15 patients. We evaluated the mRNA expression of 3 genes in the PD-1 pathway ( PD-1 , PD-L1 , and PD-L2 ) and 4 in the CTLA4 pathway ( CTLA4 , CD28 , CD80 , and CD86 ) in normal and tumoral human bladder samples by quantitative real-time reverse transcription polymerase chain reaction, with immunohistochemistry used to evaluate the protein expression of PD-1 and PD-L1 in tumor and immune cells. Results of molecular analyses were compared with survival analyses. Results As compared with normal bladder tissue, MIBC tissue showed PD-1 , PD-L1 , CTLA4 , and CD80 overexpression (59.5%, 60.7%, 84.5%, and 92.9%, respectively), whereas overexpression was lower in NMIBC tissue (22.5%, 4.2%, 35.2%, and 46.5%, respectively). The results of reverse transcription polymerase chain reaction analysis were confirmed by immunohistochemistry, with a high correlation between mRNA and protein expression. On multivariate analyses, overexpression of the studied genes was not associated with prognosis in relapse or progression of NMIBC or in recurrence-free and overall survival of MIBC. Conclusions The CTLA4 pathway appears to be deregulated along with the PD-1/PD-L1 pathway in bladder carcinogenesis, with good correlation between mRNA and protein expression endorsing the useful role of immune checkpoints, especially for a large subgroup of MIBC.
Dissemination of carcinoma cells requires the pericellular degradation of the extracellular matrix, which is mediated by membrane type 1-matrix metalloproteinase (MT1-MMP). In this article, we report ...a co–up-regulation and colocalization of MT1-MMP and atypical protein kinase C iota (aPKCι) in hormone receptor-negative breast tumors in association with a higher risk of metastasis. Silencing of aPKC in invasive breast-tumor cell lines impaired the delivery of MT1-MMP from late endocytic storage compartments to the surface and inhibited matrix degradation and invasion. We provide evidence that aPKCι, in association with MT1-MMP–containing endosomes, phosphorylates cortactin, which is present in F-actin–rich puncta on MT1-MMP–positive endosomes and regulates cortactin association with the membrane scission protein dynamin-2. Thus, cell line-based observations and clinical data reveal the concerted activity of aPKC, cortactin, and dynamin-2, which control the trafficking of MT1-MMP from late endosome to the plasma membrane and play an important role in the invasive potential of breast-cancer cells.
There is no strong and reliable predictive biomarker in head and neck squamous cell carcinoma (HNSCC) for EGFR inhibitors. We aimed to identify predictive and pharmacodynamic biomarkers of efficacy ...of afatinib, a pan-HER tyrosine kinase inhibitor, in a window-of-opportunity trial (NCT01415674). Multi-omics analyses were carried out on pre-treatment biopsy and surgical specimen for biological assessment of afatinib activity. Sixty-one treatment-naïve and operable HNSCC patients were randomised to afatinib 40 mg/day for 21-28 days versus no treatment. Afatinib produced a high rate of metabolic response. Responders had a higher expression of pERK1/2 (P = 0.02) and lower expressions of pHER4 (P = 0.03) and pRB1 (P = 0.002) in pre-treatment biopsy compared to non-responders. At the cellular level, responders displayed an enrichment of tumor-infiltrating B cells under afatinib (P = 0.02). At the molecular level, NF-kappa B signaling was over-represented among upregulated genes in non-responders (P < 0.001; FDR = 0.01). Although exploratory, phosphoproteomics-based biomarkers deserve further investigations as predictors of afatinib efficacy.
Breast cancers (BC) are rare in men and are often caused by constitutional predisposing factors. In women, mosaic BRCA1 promoter methylations (MBPM) are frequent events, detected in 4–8% of healthy ...subjects. This constitutional epimutation increases risk of early-onset and triple-negative BC. However, the role of MBPM in male BC predisposition has never been assessed. We screened 40 blood samples from men affected by BC, and performed extensive tumour analysis on MBPM-positive patients. We detected two patients carrying MBPM. Surprisingly, tumour analysis revealed that neither of these two male BCs were caused by the constitutional BRCA1 epimutations carried by the patients.
•Mosaic BRCA1 promoter methylations (MBPM) are frequent epimutations in women.•We report the first two male breast cancer patients carrying MBPM.•They presented invasive breast cancers expressing estrogen receptors.•Their breast cancers were not due to BRCA1: no homologous recombination deficiency.•Additional studies are necessary to use MBPM status to guide clinical decisions.
Management of advanced chordomas remains delicate considering their insensitivity to chemotherapy. Homozygous deletion of the regulatory gene
has been described as the most frequent genetic ...alteration in chordomas and may be considered as a potential theranostic marker. Here, we evaluated the tumor efficacy of the CDK4/6 inhibitor palbociclib, as well as the PLK1 inhibitor volasertib, in three chordoma patient-derived xenograft (PDX) models to validate and identify novel therapeutic approaches.
From our chordoma xenograft panel, we selected three models, two of them harboring a homozygous deletion of
genes, and the last one a
pathogenic variant (as control). For each model, we tested the palbociclib and volasertib drugs with pharmacodynamic studies together with RT-PCR and RNAseq analyses.
For palbociclib, we observed a significant tumor response for one of two models harboring the deletion of
(p = 0.02), and no significant tumor response in the
-mutated PDX; for volasertib, we did not observe any response in the three tested models. RT-PCR and RNAseq analyses showed a correlation between cell cycle markers and responses to palbociclib; finally, RNAseq analyses showed a natural enrichment of the oxidative phosphorylation genes (OxPhos) in the palbociclib-resistant PDX (p = 0.02).
CDK4/6 inhibition appears as a promising strategy to manage advanced chordomas harboring a loss of
. However, further preclinical studies are strongly requested to confirm it and to understand acquired or
resistance to palbociclib, in the peculiar view of a targeting of the oxidative phosphorylation genes.
Malignant adenomyoepithelioma (AME) of the breast is an exceptionally rare form of breast cancer, with a significant metastatic potential. Chemotherapy has been used in the management of advanced AME ...patients, however the majority of treatments are not effective. Recent studies report recurrent mutations in the HRAS Q61 hotspot in small series of AMEs, but there are no preclinical or clinical data showing H-Ras protein as a potential therapeutic target in malignant AMEs. We performed targeted sequencing of tumours' samples from new series of 13 AMEs, including 9 benign and 4 malignant forms. Samples from the breast tumour and the matched axillary metastasis of one malignant HRAS mutated AME were engrafted and two patient-derived xenografts (PDX) were established that reproduced the typical AME morphology. The metastasis-derived PDX was treated in vivo by different chemotherapies and a combination of MEK and BRAF inhibitors (trametinib and dabrafenib). All malignant AMEs presented a recurrent mutation in the HRAS G13R or G12S hotspot. Mutation of PIK3CA were found in both benign and malignant AMEs, while AKT1 mutations were restricted to benign AMEs. Treatment of the PDX by the MEK inhibitor trametinib, resulted in a marked anti-tumor activity, in contrast to the BRAF inhibitor and the different chemotherapies that were ineffective. Overall, these findings further expand on the genetic features of AMEs and suggest that patients carrying advanced HRAS-mutated AMEs could potentially be treated with MEK inhibitors. Keywords: Adenomyoepithelioma, HRAS, PDX, MEK inhibitor
Exome sequencing has recently identified highly recurrent MED12 somatic mutations in fibroadenomas (FAs) and phyllodes tumors (PTs). In the present study, based on a large series, we confirmed the ...presence of MED12 exon 1 and 2 mutations in 49% (41/83) of PTs, 70% (7/10) of FAs and 9.1% (1/11) of fibromatoses. We show that MED12 mutations are associated with benign behavior of phyllodes tumors, as they are detected less frequently in malignant PTs (27.6%) compared to benign (58.3%) and borderline (63.3%) PTs, respectively (p = 0.0036). Phyllodes tumors presented marked temporal heterogeneity of MED12 mutation status, as 50% (3/6) of primary and recurrent phyllodes tumor pairs with MED12 mutation presented different MED12 mutations between the primary and recurrent tumors. There was no correlation between MED12 status and genomic profiles obtained by array-CGH. MED12 mutations are associated with altered expressions of the genes involved in the WNT (PAX3, WNT3A, AXIN2), TGFB (TAGLN, TGFBR2, CTGF) and THRA (RXRA, THRA) signaling pathways.In conclusion, this study confirmed that MED12 plays a central oncogenic role in breast fibroepithelial tumorigenesis and identified a limited number of altered signaling pathways that maybe associated with MED12 mutations. MED12 exon 1 and 2 mutation status and some of the altered genes identified in this study could constitute useful diagnostic or prognostic markers, and form the basis for novel therapeutic strategies for PTs.
Recent data suggest that chemokines could be essential players in breast carcinogenesis. We previously showed that the CXC chemokine CXCL8 (interleukin-8) was overexpressed in estrogen receptor alpha ...(ERalpha)-negative breast cell lines. Analysis of CXCL8 chromosomal location showed that several CXC chemokines (CXCL1, CXCL2, CXCL3, CXCL4, CXCL4V1, CXCL5, CXCL6, CXCL7, and CXCL8) were localized in the same narrow region (360 kb in size) of chromosome 4. We thus hypothesized that they could belong to the same cluster. Quantification of these chemokines in breast tumors showed that samples expressing high CXCL8 also produced elevated levels of CXCL1, CXCL3, and CXCL5, and displayed low content of ERalpha. CXCL1, CXCL2, CXCL3, CXCL5, and CXCL8 were co-regulated both in tumors and in breast cancer cell lines. CXCL5 and CXCL8 were mainly produced by epithelial cells, whereas CXCL1, CXCL2, and CXCL3 had a high expression in blood cells. The overexpression of these chemokines in tumor cells was not the result of gene amplification, but rather of an enhanced gene transcription. Our data suggest that high CXCL8 expression in tumors is mainly correlated to activating protein-1 (AP-1) pathway and to a minor extent to NF-kappaB pathway. Interestingly, CXCL1, CXCL2, CXCL3, CXCL5, CXCL6, and CXCL8 chemokines were present at higher levels in metastases when compared with grade I and III biopsies. High levels of CXCL8, CXCL1, and CXCL3 accounted for a shorter relapse-free survival of ERalpha-positive patients treated with tamoxifen. In summary, we present evidences that multiple CXC chemokines are co-expressed in CXCL8-positive breast tumors. In addition, these chemokines could account for the higher aggressiveness of these types of tumors.
Triple-negative breast cancers (TNBC) are characterized by frequent alterations in the PI3K/AKT/mTOR signaling pathway. In this study, we analyzed PI3K pathway activation in 67 patient-derived ...xenografts (PDX) of breast cancer and investigated the anti-tumor activity of the mTOR inhibitor everolimus in 15 TNBC PDX with different expression and mutational status of PI3K pathway markers. Expression of the tumor suppressors PTEN and INPP4B was lost in 55% and 76% of TNBC PDX, respectively, while mutations in PIK3CA and AKT1 genes were rare. In 7 PDX treatment with everolimus resulted in a tumor growth inhibition higher than 50%, while 8 models were classified as low responder or resistant. Basal-like, LAR (Luminal AR), mesenchymal and HER2-enriched tumors were present in both responder and resistant groups, suggesting that tumor response to everolimus is not restricted to a specific TNBC subtype. Analysis of treated tumors showed a correlation between tumor response and post-treatment phosphorylation of AKT, increased in responder PDX, while PI3K pathway markers at baseline were not sufficient to predict everolimus response. In conclusion, targeting mTOR decreased tumor growth in 7 out of 15 TNBC PDX tested. Response to everolimus occurred in different TNBC subtypes and was associated with post-treatment increase of P-AKT.
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