Squamous Tumors Research Articles

Prognostic significance of CD204 and IDO1 expression in esophageal tumors

Introduction. Cancer of the esophagus ranks sixth in mortality among malignant neoplastic diseases. To understand the molecular mechanisms of its progression, it is necessary to study not only tumor cells directly, but also cells of the microenvironment. In this work, we studied tumor-associated macrophages and their different phenotypes using membrane protein, indoleamine 2,3‑dioxygenase-1 (IDO1) as a marker for type 1 macrophages and macrophage scavenger receptor (CD204) as a marker for type 2 macrophages.The objective of this work was to study the expression of IDO1 and CD204 in tumors of squamous cell carcinoma of the esophagus and to assess its prognostic value.Materials and methods. The study included tumor samples obtained from 48 patients with squamous cell carcinoma of the esophagus. The expression of CD204 and IDO1 was assessed by immunohistochemistry. Survival analysis was carried out by constructing survival curves using the Kaplan–Meier method. Comparison of the significance of differences was performed using the logarithmic rank test. Differences were considered statistically significant at p <0.05.Results. We analyzed the expression of CD204 and IDO1 in esophageal squamous cell carcinoma tumors. Expression of CD204 was detected in stromal macrophages in 100 % of cases and was not detected in tumor cells. We have shown that in esophageal cancer, IDO1 is expressed in both stromal and tumor cells. In tumor cells, the expression of IDO1 was found in 44 % of the samples, in stromal cells, IDO1 was expressed in 92 % of cases. No association with clinical and morphological characteristics was observed for CD204 in stromal cells and IDO1 in tumor cells. For IDO1 expressed in stromal cells, an association with the stage of the disease (p = 0.0450) and the presence of regional metastases (p = 0.0279) was observed. Survival analysis showed that CD204 is a marker of a favorable prognosis for esophageal cancer (hazard ratio 0.455, p = 0.0419).Conclusion. This study has shown that the expression of IDO1 in the tumor stroma is associated with more favorable clinical characteristics. It has also been shown that an increased content of CD204+ macrophages is a marker of a good prognosis for esophageal cancer.

Abstract 2117: Immunomodulatory functions of SMYD3 in HPV-negative head and neck squamous cell carcinoma

Abstract Background: Head and neck squamous cell carcinoma (HNSCC) causes approximately 10,000 deaths annually in the United States, with human-papilloma-virus (HPV)-negative patients having a particularly poor prognosis. Pembrolizumab, a programmed-death-1 (PD-1) antibody, was recently approved as a first-line therapy for patients with relapsed disease, however response rates are as low as 19%, underscoring the need for an improved understanding of immunotherapy resistance mechanisms. We have previously shown that HPV-negative HNSCC tumors with higher mRNA levels of SET and MYND Domain Containing 3 (SMYD3), a chromatin modifier known to trimethylated H3K4 (H3K4me3), have significantly lower mRNA levels of CD8 and CD8+ T-cell attracting chemokines, and that SMYD3 depletion in HNSCC cells in vitro leads to upregulation of CD8+ T-cell attracting chemokines. The goal of this work was to elucidate epigenetic mechanisms of immune evasion mediated by SMYD3 in HPV-negative HNSCC. Methods: siRNA- mediated SMYD3 knockdown was performed for 3 days to investigate immuno-modulatory epigenetic mechanisms mediated by SMYD3. RT-qPCR for immune-related genes, Western blotting for histone marks, ChIP-sequencing for H3K4me3, ChIP-qPCRs to determine genomic interactions of SMYD3 and ATAC-sequencing were performed. SMYD3 and CD8 immunohistochemical staining (IHC) of normal squamous, dysplastic epithelium and HPV-negative HNSCC tumors was also performed. Results: siRNA mediated knockdown of SMYD3 resulted in enrichment of inflammatory pathways and upregulation of type 1 interferon response and antigen presentation machinery genes in HNSCC cell lines. Immunoblotting for histone marks showed no reduction in H3K4me3 following SMYD3 depletion for 3 days. ChIP-sequencing for H3K4me3 showed differential distribution pattern with an increase of H3K4me3 peaks on immune-related genes, and a decrease of H3K4me3 on UHRF1, a reader of the repressive histone mark H3K9me3. RNA-seq, RT-PCR and ChIP-qPCR showed that SMYD3 may regulate the transcription of UHRF1 by binding to its promoter. SMYD3 depletion also led to decreased protein levels of UHRF1. ChIP for UHRF1 and H3K9me3 showed that UHRF1 binds directly on the promoters of CXCL9 and CXCL10 which are enriched for H3K9me3. IHC on Normal Squamous Epithelium and Squamous Cell Carcinoma tissues of increasing cancer stages showed increase in SMYD3 levels with the higher stage of cancer, and an inverse correlation with CD8+ T cell infiltration within the tumors. Conclusion: This is the first study reporting that the chromatin modifier SMYD3 may attenuate type I IFN responses in HPV-negative HNSCC by regulating the expression of a major epigenetic regulator, UHRF1, which may silence the expression of immune-related genes through H3K9me3. Citation Format: Nupur Nigam, Benjamin Jonah Bernard, Kyunghee Burkitt, Sohyoung Kim, Yvette Robbins, Richard L. Bennett, Jonathan D. Licht, Vassiliki Saloura. Immunomodulatory functions of SMYD3 in HPV-negative head and neck squamous cell carcinoma [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 2117.

Stratification of urothelial bladder carcinoma depending on immunohistochemical expression of GATA3 and CK5/6

ABSTRACT Bladder urothelial carcinoma (BUC) has two pathways with distinct molecular features and prognosis, non-muscle invasive (NMI) and muscle invasive (MI) tumors. The aim is to investigate the expression of GATA3 and CK5/6 in BUC with correlation to clinicopathologic parameters, including their impact on survival beside their potential use to stratify cases into prognostic subgroups. This study included 80 cases of BUC stained immunohistochemically by GATA3 and CK5/6. The cases were divided into four groups regarding expression status of both markers (luminal, basal, mixed, and null). GATA3 percentage of expression decreased in urothelial carcinoma with squamous differentiation, MI tumors, high-grade tumors, tumors with involved lymph nodes, presence of perineural invasion, presence of bilharziasis, presence of lympho-vascular invasion, and high mitotic count. CK5/6 positivity was higher in urothelial carcinoma cases with squamous differentiation, MI tumors, and presence of perineural invasion. Pure urothelial carcinoma and NMI were in favor of luminal group (GATA3 +ve/CK5/6 −ve). Univariate analysis showed that the presence of bilharziasis was associated with shorter PFS (p = .04). GATA3 and CK5/6 could be used for the stratification of urothelial bladder carcinoma into subtypes with different characteristics. Luminal bladder cancer represents the most common type (60%) that carries favorable features. Bilharziasis-associated urothelial carcinoma carries poor outcome manifested by short PFS.

Evaluation of carbonic anhydrase IX as a potential therapeutic target in urothelial carcinoma

ObjectiveCarbonic anhydrase IX (CA9) is important in the regulation of intra- and extracellular pH in solid tumors, contributing to cell growth and invasion. In urothelial carcinoma (UC), CA9 has been identified as a urinary marker for disease detection, but its biologic role is unknown. To date, differential gene expression patterns of CA9 in various molecular subtypes and potential effects of CA9 inhibition in UC cells are unknown. We aimed to investigate the function of CA9 and the effects of CA9 inhibition in invasive UC. MethodsImmunohistochemistry was used to assess CA9 expression in a cohort of 153 patients undergoing radical cystectomy. CA9 expression was correlated with molecular subtype by analysis of the TCGA data and of our own cohort of 223 patients with invasive UC receiving neoadjuvant chemotherapy. CA9 expression was assessed in a panel of 12 UC cell lines by Western Blot and qPCR, and multiple siRNAs were used to silence CA9 in 2 cell lines. Effects of CA9 silencing on cell growth, migration, and invasion were assessed. We also used the small molecule inhibitor U-104 to inhibit CA9 in vitro and in an orthotopic xenograft model. ResultsCA9 expression was higher in cancer tissue compared to benign urothelium and was particularly highly expressed in luminal papillary and basal squamous tumors. CA9 expression did not correlate with outcome after neoadjuvant chemotherapy and/or radical cystectomy. Silencing of CA9 by siRNA diminished invasion but did not induce a consistent change of cell growth and migration. Treatment with U-104 led to cell growth reduction only at high concentrations in vitro and failed to have a significant effect on tumor growth in vivo. ConclusionsThe present study confirms over-expression of CA9 in UC and for the first time shows a correlation with molecular subtypes. However, CA9 expression showed no association with the outcome of patients with muscle invasive bladder cancer and inhibition of CA9 did not lead to a consistent inhibition of tumor growth. Based on these data, CA9 exhibits a role neither as a predictive or prognostic marker nor as a therapeutic target in invasive UC.

Evaluation of Histopathological Risk Model in a Cohort of Oral Squamous Cell Carcinoma Patients Treated with Accompanying Neck Dissection

To investigate the applicability of the validated histological risk model in a cohort of oral cavity squamous cell carcinoma patients treated concurrently with neck dissections. Primary tumours from 85 patients with primary excision of T1 and T2 Oral Squamous Cell Carcinomas (TNM 7th edition) including neck dissection were scored by three pathologists in consensus according to the validated risk model. The risk score data, along with traditional dataset values, were analysed to determine possible association with nodal metastasis and extracapsular spread. Seventy-two patients (54%) were classified with low or intermediate risk and 62 (46%) patients were ‘high risk’. A chi squared test showed that cases with nodal metastasis were highly statistically significant with the overall risk model score (X2 = 22.62 p = 0.0001). None of the neck dissections from tumours with low risk score showed evidence of metastasis (NPV = 100%) suggesting the risk score may also be a useful tool for predicting an absence of metastasis. Risk assessment of low-stage oral squamous cell carcinoma primary tumours may be predictive of the presence or absence of metastasis at presentation. Knowledge of the risk score and its constituent parts may inform treatment decisions at multidisciplinary meetings. Low risk squamous cell carcinoma may be a rare variant with low metastatic potential and excellent long-term survival.

653 Sequencing of cutaneous squamous cell carcinoma primary tumors and patient-matched metastases reveals ALK as a driver in metastases and low mutational concordance in immunocompromised patients

653 Sequencing of cutaneous squamous cell carcinoma primary tumors and patient-matched metastases reveals ALK as a driver in metastases and low mutational concordance in immunocompromised patients

Management of OSSN by different modalities of treatment

Objectives: To study the Ocular surface squamous (OSSN) neoplasm in terms of demographics, clinical presentation, histopathology and treatment. Materials and Methods: This is a histopathological hospital based prospective comparative interventional case series carried out in the Department of Ophthalmology, S.P. Medical College and associated group of hospital in collaboration with Pathology Department.. The study was carried out from December, 2017 to December, 2019. The study included 22 consecutive cases of OSSN of either age and sex. In our study three groups were formed based on different modalities for treatment of OSSN-Surgery plus Mitomycin [MMC] (0.04%) 4 cycles, Surgery ,Only MMC (0.04%) 4 cycles. Results: OSSN was found with greater frequency in male patients (male/female ratio: 2.7/1), residents of rural area (rural/urban ratio: 3.4/1), older age group (mean age SD: 54.1013.17) and those engaged in outdoor activity. On Histopathological examination 15 cases 68.18% were reported with squamous cell carcinoma, 5 cases (22.73%) with severe dysplasia and two cases (9.09) with carcinoma in-situ. Surgery plus MMC was the most effective mode of treatment in these neoplasia. Conclusion: Surgery plus MMC was the most effective mode of treatment in OSSN. These types of tumours can be treated with only mitomycin-c in cases where surgery was challenging. Young patients presenting with OSSN must be screened for HIV. Keywords: OSSN, Mitomycin-c, Ocular.

Comparison of FDG and FMISO uptakes and distributions in head and neck squamous cell cancer tumors

PurposeGlycolysis is increased by hypoxia, suggesting a possible correlation between the accumulation of 2-[18F]fluoro-2-deoxy-D-glucose (FDG) in malignant tumors and regional hypoxia defined by 1H-1-(3-[18F]fluoro-2-hydroxypropyl)-2-nitroimidazole (FMISO) PET. The aim of this study is to investigate the intra-tumoral spatial distribution and quantitative relationship between FDG and FMISO in a cohort of head and neck squamous cell cancer (HNSCC) patients.MethodsTwenty HNSCC patients with 20 primary tumors and 19 metastatic lymph nodes (LNs) underwent FDG and FMISO PET within 1 week. The metabolic target volume (MTV) was defined on the FDG PET images using a region growing algorithm. The hypoxic volume (HV) was defined by the volume of voxels in an FMISO image within the MTV that satisfy a tumor-to-blood ratio (T/B) greater than 1.2. FDG and FMISO lesions were co-registered, and a voxel-by-voxel correlation between the two datasets was performed. FDG and FMISO TVs’ SUVs were also compared as well as the intra-tumoral homogeneity of the two radiotracers. Separate analysis was performed for the primary tumors and LNs.ResultsTwenty-six percent of the primary tumors and 15% of LNs showed a strong correlation (R > 0.7) between FDG and FMISO intra-tumor distributions when considering the MTV. For the HV, only 19% of primary tumors and 12% of LN were strongly correlated. A weak and moderate correlation existed between the two markers SUVavg, and SUVmax in the case of the primary tumors, respectively. However, this was not the case for the LNs. Good concordances were also observed between the primary tumor’s and LNs HV SUVavgs as well as between the corresponding hypoxic fractions (HF’s).ConclusionsA moderate correlation between FDG and hypoxia radiotracer distribution, as measured by FMISO, seems to exist for primary tumors. However, discordant results were found in the case of LNs. Hypoxia appears to be the dominant driver of high FDG uptake in selected tumors only, and therefore FDG PET images cannot be used as a universal surrogate to identify or predict intra-tumor hypoxia.

Rare Histolopathologic Variants in Bladder Cancer

The heterogeneous spectrum of bladder cancer comprises the coexistence of conventional urothelial carcinoma (UC) with its variants as well as the non-urothelial carcinoma (including squamous and glandular tumors). Since the official classification of rare histologic subtypes, by the World Health Organization (WHO) in 2004, uropathologists and urologists are paying more attention to the role of these subtypes as potential prognostic markers. Most of these rare variants have been associated with increased risk of progression and poor prognosis. Therefore, patients diagnosed with some of the histologic subtypes, have been classified to “the very high risk group” of recurrence and progression, although it has not yet been clarified if this is due to advanced stages at presentation and underdiagnosis or due to the aggressiveness of each variant, as an independent factor. This review discusses the most common variants of bladder cancer (urothelial carcinoma with squamous and/or glandular differentiation, pure squamous carcinoma, pure adenocarcinoma, urachal carcinoma, nested pattern, microcystic, micropapillary, small cell carcinoma, plasmacytoid, sarcomatoid, and lymphoepithelial like carcinoma), outlining the recent advances regarding the diagnosis, differential diagnosis, treatment and clinical significance for each one. High index of suspicious is required by the uropathologists for detection of these variants and well-designed multi-institutional studies are necessary in order the specific treatment strategies for these patients to be established.

Targeting resistance to radiation-immunotherapy in cold HNSCCs by modulating the Treg-dendritic cell axis

BackgroundNumerous trials combining radiation therapy (RT) and immunotherapy in head and neck squamous cell carcinoma (HNSCC) are failing. Using preclinical immune cold models of HNSCC resistant to RT-immune checkpoint inhibitors,...

Changes in the therapeutic landscape of oesophago-gastric cancers.

This article reviews recent randomised clinical trials on systemic treatment of oesophago-gastric cancers in the perioperative and metastatic setting. Adding nivolumab to first-line chemotherapy improved survival in patients with metastatic gastric/gastro-oesophageal junction/oesophageal adenocarcinoma with PD-L1 combined positive score (CPS) ≥ five in a global trial and progression-free survival in metastatic gastric/gastro-oesophageal junction cancers in an Asian trial. The addition of pembrolizumab to first-line chemotherapy improved survival in metastatic oesophageal cancer patients, with the most benefit in oesophageal squamous cancer and tumours with high PD-L1 expression (CPS ≥ 10). Adjuvant nivolumab improved disease-free survival (DFS) in resectable oesophageal cancer patients with residual pathologic disease after neoadjuvant chemoradiation. In human epidermal growth factor receptor 2 (HER2)-positive oesophago-gastric adenocarcinoma, a phase II trial showed improved DFS when pertuzumab and trastuzumab were added to perioperative FLOT (5-fluorouracil/leucovorin, oxaliplatin, docetaxel). Another phase II trial showed improved response rates and survival in pretreated metastatic HER2-positive gastric and gastrooesophageal junction cancer patients who received the antibody-drug conjugate trastuzumab deruxtecan compared to physician's choice of chemotherapy. Chemo-immunotherapy combinations will become the new standard of care for some patients with metastatic oesophago-gastric cancers. Adjuvant nivolumab is a new option for oesophageal cancer patients with poor response after neoadjuvant chemoradiation.

Molecular characterization of lung squamous cell carcinoma tumors reveals therapeutically relevant alterations.

Introduction: Unlike lung adenocarcinoma patients, there is no FDA-approved targeted-therapy likely to benefit lung squamous cell carcinoma patients.Materials and Methods: We performed survival analyses of lung squamous cell carcinoma patients harboring therapeutically relevant alterations identified by whole exome sequencing and mass spectrometry-based validation across 430 lung squamous tumors.Results: We report a mean of 11.6 mutations/Mb with a characteristic smoking signature along with mutations in TP53 (65%), CDKN2A (20%), NFE2L2 (20%), FAT1 (15%), KMT2C (15%), LRP1B (15%), FGFR1 (14%), PTEN (10%) and PREX2 (5%) among lung squamous cell carcinoma patients of Indian descent. In addition, therapeutically relevant EGFR mutations occur in 5.8% patients, significantly higher than as reported among Caucasians. In overall, our data suggests 13.5% lung squamous patients harboring druggable mutations have lower median overall survival, and 19% patients with a mutation in at least one gene, known to be associated with cancer, result in significantly shorter median overall survival compared to those without mutations. Conclusions: We present the first comprehensive landscape of genetic alterations underlying Indian lung squamous cell carcinoma patients and identify EGFR, PIK3CA, KRAS and FGFR1 as potentially important therapeutic and prognostic target.

Genomic characterization of bladder cancer with variant histology.

470 Background: Up to 25% of tumors are of pure variant or mixed urothelial and variant histology. The presence of variant histology may be associated with more advanced stage at presentation and a poorer response to systemic therapy. While histomorphologic assessment provides important prognostic information, genomic analysis of tumors can provide important insight into the biology of disease and inform treatment. In this analysis we performed genomic sequencing of tumors from patients with bladder cancer with variant histology. Methods: Our prospectively generated institutional cohort of molecularly profiled bladder and upper tract tumors contains over 2,000 samples including nearly 300 primary bladder tumor samples from patients with variant histology. Targeted sequencing with MSK-IMPACT was used to identify alterations in cancer-associated genes and to describe trends across variant subtypes. To explore and compare tumor and immune cell heterogeneity, single-cell RNA sequencing (scRNA-seq) was performed on a subset of specimens. Results: Our cohort included patients with pure urothelial carcinoma not otherwise specified (NOS), as well as squamous, small cell, pure adenocarcinoma and urothelial carcinoma with glandular differentiation, micropapillary, nested, and plasmacytoid variants. Compared with urothelial carcinoma NOS, nearly all small cell tumors had mutations in TP53, RB1, and TERT. Squamous tumors had similar mutational frequencies as urothelial carcinoma NOS. Pure adenocarcinoma had frequent mutations in TP53, KRAS, and PIK3CA, resembling colorectal adenocarcinomas, while urothelial carcinoma with glandular differentiation resembled NOS. Micropapillary variant commonly had ERBB2 amplifications. Nested variant was more commonly found to have RHOA mutations and FOXA1 amplifications. Finally, nearly all plasmacytoid variants had pathognomonic alterations in CDH1. To further explore heterogeneity in tumor and immune cell populations, scRNA-seq was performed on four samples from patients with urothelial carcinoma NOS, squamous, micropapillary, and nested variants, showing distinct tumor cell clusters and varying contributions of immune cells from each variant. Conclusions: While the distribution of oncogenic mutations differed among distinct histologic variants, a pathognomonic DNA alteration was not found for most variant histologic subtypes. Within the context of a larger effort to characterize bladder cancer with variant histology, scRNA-seq may reveal differences in immune cell population infiltrates. Further efforts will aim to characterize these cohorts with whole exome sequencing and mutational signatures, and increase the number of samples per histology and representation of variant histologies for scRNA-seq.

NRF2 Activation Promotes Aggressive Lung Cancer and Associates with Poor Clinical Outcomes.

Stabilization of the transcription factor NRF2 through genomic alterations in KEAP1 and NFE2L2 occurs in a quarter of patients with lung adenocarcinoma and a third of patients with lung squamous cell carcinoma. In lung adenocarcinoma, KEAP1 loss often co-occurs with STK11 loss and KRAS-activating alterations. Despite its prevalence, the impact of NRF2 activation on tumor progression and patient outcomes is not fully defined. We model NRF2 activation, STK11 loss, and KRAS activation in vivo using novel genetically engineered mouse models. Furthermore, we derive a NRF2 activation signature from human non-small cell lung tumors that we use to dissect how these genomic events impact outcomes and immune contexture of participants in the OAK and IMpower131 immunotherapy trials. Our in vivo data reveal roles for NRF2 activation in (i) promoting rapid-onset, multifocal intrabronchiolar carcinomas, leading to lethal pulmonary dysfunction, and (ii) decreasing elevated redox stress in KRAS-mutant, STK11-null tumors. In patients with nonsquamous tumors, the NRF2 signature is negatively prognostic independently of STK11 loss. Patients with lung squamous cell carcinoma with low NRF2 signature survive longer when receiving anti-PD-L1 treatment. Our in vivo modeling establishes NRF2 activation as a critical oncogenic driver, cooperating with STK11 loss and KRAS activation to promote aggressive lung adenocarcinoma. In patients, oncogenic events alter the tumor immune contexture, possibly having an impact on treatment responses. Importantly, patients with NRF2-activated nonsquamous or squamous tumors have poor prognosis and show limited response to anti-PD-L1 treatment.

Integrative Analysis of miRNAs Identifies Clinically Relevant Epithelial and Stromal Subtypes of Head and Neck Squamous Cell Carcinoma

The objective of this study is to characterize the role of miRNAs in the classification of head and neck squamous cell carcinoma (HNSCC). Here, we analyzed 562 HNSCC samples, 88 from a novel cohort and 474 from The Cancer Genome Atlas, using miRNA microarray and miRNA sequencing, respectively. Using an integrative correlations method followed by miRNA expression-based hierarchical clustering, we validated miRNA clusters across cohorts. Evaluation of clusters by logistic regression and gene ontology approaches revealed subtype-based clinical and biological characteristics. We identified two independently validated and statistically significant (P < 0.01) tumor subtypes and named them "epithelial" and "stromal" based on associations with functional target gene ontology relating to differing stages of epithelial cell differentiation. miRNA-based subtypes were correlated with individual gene expression targets based on miRNA seed sequences, as well as with miRNA families and clusters including the miR-17 and miR-200 families. These correlated genes defined pathways relevant to normal squamous cell function and pathophysiology. miRNA clusters statistically associated with differential mutation patterns including higher proportions of TP53 mutations in the stromal class and higher NSD1 and HRAS mutation frequencies in the epithelial class. miRNA classes correlated with previously reported gene expression subtypes, clinical characteristics, and clinical outcomes in a multivariate Cox proportional hazards model with stromal patients demonstrating worse prognoses (HR, 1.5646; P = 0.006). We report a reproducible classification of HNSCC based on miRNA that associates with known pathologically altered pathways and mutations of squamous tumors and is clinically relevant.

CheckMate 9LA: broadening treatment options for patients with non-small-cell lung cancer.

The use of immune-checkpoint inhibitors targeting the CTLA-4, PD-1, or PD-L1 signalling axis in the modulation of anti-tumour T-cell activity has revolutionised the treatment of lung cancer in different settings.1 In patients with PD-L1 expression of at least 50%, pembrolizumab (anti PD-1) and atezolizumab (anti PD-L1) have been approved by the US Food and Drug Administration as first-line single-agent treatments because they significantly prolong overall survival compared with platinum-based chemotherapy, in patients with both squamous and non-squamous tumours without sensitising EGFR mutations or ALK rearrangements.

Contemporary Molecular Classification of Urinary Bladder Cancer.

The significant heterogeneity in the clinical outcome among patients with bladder cancer has highlighted the existence of different biological subtypes of muscle-invasive and non-muscle-invasive bladder cancer. Transcriptional profiling studies revealed that primary bladder cancers can be grouped into 'intrinsic' basal and luminal molecular subtypes. Luminal tumors have a papillary configuration and express markers of urothelial differentiation (uroplakins, cytokeratin 20) fibroblast growth factor 3 (FGFR3), E-cadherin and early cell-cycle genes. On the contrary, basal tumors express markers of the basal layer of the urothelium (cluster of differentiation 44, cytokeratin 5/6 and cytokeratin 14); some show squamous differentiation. Patients with basal tumors respond better to immune checkpoint inhibitors and have a worse prognosis than those with luminal tumors, who respond better to FGFR3 and human epidermal growth factor receptor 2. Patients with squamous differentiation tumors show better response to agents targeting epidermal growth factor receptor. The aim of this review was to highlight the chronological order of research performed in the field of the molecular classification of bladder cancer, with particular emphasis on prototypical research projects and recent advances. If prospective studies confirm the association of bladder cancer molecular subtypes with different responses and prognoses to targeted therapies, molecular subtyping will be incorporated into bladder cancer management.

Differences in TCR repertoire and T cell activation underlie the divergent outcomes of antitumor immune responses in tumor-eradicating versus tumor-progressing hosts

BackgroundAntitumor immunity is highly heterogeneous between individuals; however, underlying mechanisms remain elusive, despite their potential to improve personalized cancer immunotherapy. Head and neck squamous cell carcinomas (HNSCCs) vary significantly in...

Fat1 deletion promotes hybrid EMT state, tumour stemness and metastasis.

FAT1, which encodes a protocadherin, is one of the most frequently mutated genes in human cancers1-5. However, the role and the molecular mechanisms by which FAT1 mutations control tumour initiation and progression are poorly understood. Here, using mouse models of skin squamous cell carcinoma and lung tumours, we found that deletion of Fat1 accelerates tumour initiation and malignant progression and promotes a hybrid epithelial-to-mesenchymal transition (EMT) phenotype. We also found this hybrid EMT state in FAT1-mutated human squamous cell carcinomas. Skin squamous cell carcinomas in which Fat1 was deleted presented increased tumour stemness and spontaneous metastasis. We performed transcriptional and chromatin profiling combined with proteomic analyses and mechanistic studies, which revealed that loss of function of FAT1 activates a CAMK2-CD44-SRC axis that promotes YAP1 nuclear translocation and ZEB1 expression that stimulates the mesenchymal state. This loss of function also inactivates EZH2, promoting SOX2 expression, which sustains the epithelial state. Our comprehensive analysis identified drug resistance and vulnerabilities in FAT1-deficient tumours, which have important implications for cancer therapy. Our studies reveal that, in mouse and human squamous cell carcinoma, loss of function of FAT1 promotes tumour initiation, progression, invasiveness, stemness and metastasis through the induction of a hybrid EMT state.

Radiotherapy enhances uptake and efficacy of 90Y-cetuximab: A preclinical trial

Background and purposeSystemic molecular radiotherapy utilizes internal irradiation by radionuclide-labeled tumor-targeting agents with the potential to destroy (micro-)metastases. However, doses that are applicable in solid tumors do not reach the levels nessecary for tumor control. Thus, the combination of molecular and external radiotherapy is a promising treatment strategy, as enhanced tumor doses can be delivered with and without minor overlapping toxicities. Here, we combined a 90Y-labeled anti-EGFR antibody (Cetuximab) with clinically relevant fractionated radiotherapy in a preclinical trial using head and neck squamous cell carcinoma xenograft tumors. Materials and methodsTo model 90Y-Cetuximab uptake for treatment schedule optimization, FaDu-bearing mice were injected with near-infrared-labeled-Cetuximab at different time points during radiotherapy with differing doses. Cetuximab uptake was longitudinally followed by in vivo-optical imaging. Tumor control probability experiments with fractionated radiotherapy (30 fx, 6 weeks, 8 dose groups/ arm) in combination with 90Y-Cetuximab were performed to test the curative potential. ResultsImaging of near-infrared-labeled-Cetuximab uptake revealed that low to moderate external beam doses can enhance antibody uptake. Using the optimized schedule, combination of molecular and external radiotherapy using 90Y-Cetuximab at a dose that did not result in permanent tumor inactivation in previous experiments, led to substantially increased tumor control compared to radiotherapy alone. ConclusionOur results indicate that combination of radiolabeled therapeutics with clinically relevant fractionated radiotherapy has a remarkable potential to improve curative treatment outcome. Application of some radiation dose prior to injection may improve drug uptake and enable patient stratification and treatment personalization via a corresponding PET-tracer during therapy.