Squamous Cell Carcinoma Tumors Research Articles

The Biological Significance Of AFF4: Promoting Transcription Elongation, Osteogenic Differentiation and Tumor Progression.

As a member of the AF4/FMR2 (AFF) family, AFF4 is a scaffold protein in the superelongation complex (SEC). In this mini-view, we discuss the role of AFF4 as a transcription elongation factor that mediates HIV activation and replication and stem cell osteogenic differentiation. AFF4 also promotes the progression of head and neck squamous cell carcinoma, leukemia, breast cancer, bladder cancer and other malignant tumors. The biological function of AFF4 is largely achieved through SEC assembly, regulates SRY-box transcription factor 2 (SOX2), MYC, estrogen receptor alpha (ESR1), inhibitor of differentiation 1 (ID1), c-Jun and noncanonical nuclear factor-κB (NF-κB) transcription and combines with fusion in sarcoma (FUS), unique regulatory cyclins (CycT1), or mixed lineage leukemia (MLL). We explore the prospects of using AFF4 as a therapeutic in Acquired immunodeficiency syndrome (AIDS) and malignant tumors and its potential as a stemness regulator.

Pan-cancer prognosis, immune infiltration, and drug resistance characterization of lung squamous cell carcinoma tumor microenvironment-related genes

BackgroundThe tumor microenvironment (TME) plays an important role in cancer development; however, its implications in lung squamous cell carcinoma (LUSC) and pan-cancer have been poorly understood. MethodsIn this study, The Cancer Genome Atlas (TCGA) and Estimation of Stromal and Immune cells in Malignant Tumor tissue using Expression Data (ESTIMATE) datasets were applied to identify differentially expressed genes. Additionally, online public databases were utilized for in-depth bioinformatics analysis of pan-cancer datasets to investigate the prognostic implications of TME-related genes further. ResultsOur study demonstrated a significant association between stromal scores, immune scores, and specific clinical characteristics in LUSC patients. C3AR1, CSF1R, CCL2, CCR1, and CD14 were identified as prognostic genes related to the TME. All TME-related prognostic genes demonstrated varying degrees of correlation with immune infiltration subtypes and tumor cell stemness. Moreover, our study revealed that TME-related prognostic genes, particularly C3AR1 and CCR1, might contribute to drug resistance in cancer cells. ConclusionsThe identified TME-related prognostic genes, particularly C3AR1 and CCR1, have potential implications for understanding and targeting drug resistance mechanisms in cancer cells.

The Tumor Stroma of Squamous Cell Carcinoma: A Complex Environment That Fuels Cancer Progression.

The tumor microenvironment (TME), a complex assembly of cellular and extracellular matrix (ECM) components, plays a crucial role in driving tumor progression, shaping treatment responses, and influencing metastasis. This narrative review focuses on the cutaneous squamous cell carcinoma (cSCC) tumor stroma, highlighting its key constituents and their dynamic contributions. We examine how significant changes within the cSCC ECM-specifically, alterations in fibronectin, hyaluronic acid, laminins, proteoglycans, and collagens-promote cancer progression, metastasis, and drug resistance. The cellular composition of the cSCC TME is also explored, detailing the intricate interplay of cancer-associated fibroblasts (CAFs), mesenchymal stem cells (MSCs), endothelial cells, pericytes, adipocytes, and various immune cell populations. These diverse players modulate tumor development, angiogenesis, and immune responses. Finally, we emphasize the TME's potential as a therapeutic target. Emerging strategies discussed in this review include harnessing the immune system (adoptive cell transfer, checkpoint blockade), hindering tumor angiogenesis, disrupting CAF activity, and manipulating ECM components. These approaches underscore the vital role that deciphering TME interactions plays in advancing cSCC therapy. Further research illuminating these complex relationships will uncover new avenues for developing more effective treatments for cSCC.

Suspect dyskeratotic neoformations in a 7-year-old child with keratitis-ichthyosis-deafness syndrome: diagnostic, surgical and wound care management

Keratitis-ichthyosis-deafness syndrome (KID) is a rare genetic disorder characterized by the triad of hyperkeratosis, ichthyosis, and congenital prelingual sensorineural deafness, with less than 100 cases described in the literature. In addition to many other extra-cutaneous manifestations, these patients are burdened by two principal increased risk factors involving the skin: the risk of developing infections and the risk of developing malignant skin tumors, especially Squamous Cell Carcinoma and Trichilemmal tumors. We present the case of a 7-year-old girl with a unique genetic variant described to date, who developed 4 dyskeratotic neoformation. Since the dermatoscopic examination was not sufficient to exclude malignancy, excisional and punch biopsies were used. Nonetheless, healing was challenging, with wound dehiscence and infection onset. Ad hoc wound care management resorting to negative pressure therapy and advanced medical honey-based dressings was necessary to achieve complete wound healing.

The small extracellular vesicle-mediated intercellular transformation of CXCR1Low to CXCR1High tumour cells promotes the progression of head and neck squamous cell carcinoma.

The heterogeneity of tumour cells enables cancers to dynamically adapt to microenvironmental stresses during progression. However, the mechanism underlying the transformation and intercellular communication between heterogeneous tumour cells has remained elusive. Here, we report a "contagion model" that mediates intercellular transformation between heterogeneous tumour cells which facilitates tumour progression. Initially identifying heterogeneous expression of CXCR1, a receptor for interleukin-8, in head and neck squamous cell carcinoma (HNSCC) tumour cells, we found that CXCR1High tumour cells had higher abilities for migration and invasion. Following interleukin-8-mediated activation, CXCR1High cells transformed CXCR1Low cells into CXCR1High cells through the secretion of small extracellular vesicles (sEVs), which increased the proportion of CXCR1High cells and facilitated tumour progression. Mechanistically, we demonstrate that sEVs derived from interleukin-8-activated CXCR1High cells contain high levels of ATP citrate lyase (ACLY), which acetylates NF-κB p65 and facilitates its nuclear translocation to transcribe CXCR1 in CXCR1Low cells. That process could be inhibited by Bempedoic acid, an FDA-approved ACLY-targeted drug. Taken together, our study reveals an sEV-mediated transformation of CXCR1Low to CXCR1High cells that promotes HNSCC progression. This provides a new paradigm to explain the dynamic changes of heterogeneous tumour cells, and identifies Bempedoic acid as a potential drug for HNSCC treatment.

Abstract 6658: TcE armed oncolytic virus VSV-GP combines oncolysis and T-cell retargeting for improved efficacy

Abstract Background: Oncolytic viruses, such as the chimeric vesicular stomatitis virus variant VSV-GP have dual modes of action, direct tumor-cell killing, and activation of tumor-specific immunity. While tumor cells deficient in type I interferon (IFN) response are permissive to VSV-GP replication and killing, IFN competent tumor cells are protected from VSV-GP-mediated oncolysis. Our previous data demonstrated that VSV-GP therapy turns immunologically ‘cold’ tumors ‘hot’ by increasing infiltration of T cells into the tumor. The aim of this study was to use the VSV-GP platform to locally express a T cell engager (TcE) molecule to redirect these T cells to destroy non-permissive IFN competent tumor cells expressing the target of the TcE on their cell surface. Methods: We selected EpCAM as the target antigen and used a bispecific EpCAM-TcE molecule consisting of two variable single chain fragments against EpCAM and CD3, respectively. VSV-GP encoding EpCAM-TcE (VSV-GP-EpCAM-TcE) or an invariant control TcE (VSV-GP-TNP-TcE) were generated as previously described. T cells were co-cultured with human target cells expressing EpCAM on their cell surface, either infected with the VSV-GP-EpCAM-TcE virus or with supernatant from VSV-GP-EpCAM-TcE infected cells. T cell activation, proliferation, degranulation and cytokine secretion were analyzed by flow cytometry and multiplex cytokine assays as a measure of TcE mediated cross-linking of T cells to their target on cancer cells. Patient-derived head and neck squamous cell carcinoma (HNSCC) tumors were sectioned into approximately 200 µM slices and infected with the virus. T cell activation was measured by cytokine secretion. The therapeutic potential of VSV-GP-EpCAM-TcE was tested in vivo in cell-line derived xenograft (CDX) models implanted in immunodeficient mice humanized with donor-derived PBMCs or CD34+ cells. Results: Virus fitness was maintained for VSV-GP encoding the TcE molecule. Using co-culture assays, we demonstrated that EpCAM-TcE molecule is successfully expressed by VSV-GP and can activate both CD4+ and CD8+ T cells resulting in proliferation, degranulation, and cytokine secretion. Furthermore, we validated the concept using patient-derived HNSCC tumor slices which are representative of complex human tumor ecosystems. We could confirm that cancer cells infected by VSV-GP-EpCAM-TcE virus express functional TcE molecule and activates T cells to secrete IFNγ and TNFα. Finally, we tested the concept in two different CDX models where VSV-GP-EpCAM-TcE showed improved tumor growth inhibition due to a combined effect of oncolysis and T cell activation by EpCAM-CD3 TcE. Summary: The oncolytic virus VSV-GP can be successfully armed with a TcE to redirect tumor-infiltrating T cells to destroy tumor cells which are not permissive to viral replication. This resulted in an enhanced therapeutic efficacy compared to just the oncolytic effect. Citation Format: Aparna Ponnurangam, Theresa Schwaiger, Sophie Walter, Simone Bartl, Melissa Mayr, Monika Petersson, Tanja Schoenberger, Fabian Heinemann, Peter Gross, Wolfgang Rist, Srinath Kasturirangan, Charlotte Lempp, Jutta Petschenka, Krishna Das, Nolden Tobias. TcE armed oncolytic virus VSV-GP combines oncolysis and T-cell retargeting for improved efficacy [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 6658.

Abstract 2280: HPV integration identifies emerging oncogenes and carcinogenic mechanisms, potentially indicating tumor recurrences

Abstract HPV integration events in Head and neck squamous cell carcinomas (HNSCC) are strongly associated with carcinogenesis and tumor progression. Previous studies have elucidated the mechanisms and structures of HPV-human fusion events, pinpointing potential integration “hotspots” (i.e. genes with nearby HPV integration in recurrent patients). However, none has comprehensively investigated the effects of HPV integration on both HPV and human gene expression, nor assessed the clinical implications of these bidirectional expression changes. In this study, we conducted bulk RNA sequencing on 67 Formalin-Fixed Paraffin-Embedded Oropharyngeal Squamous Cell Carcinoma (OPSCC) tumor samples from the University of Michigan hospital, and analyzed them in conjunction with bulk and single cell RNA-seq from another >200 HPV(+) HNSCC patients from four previous studies. Among the 117 samples confidently identified as HPV integration positive, we recaptured all previously known integration “hotspot” genes as well as several novel ones that have altered expression in the integrated samples. Exploring the impact of HPV integration on the expression of human and HPV genes, we found that HPV integration in HNSCC is strongly associated with keratinization, immune response, and the development of HPV(+) HNSCC subtypes. Upon HPV integration, expression of non-oncogenic HPV genes is often lost. We hypothesized that the expression ratio of these potentially HPV immunogenic genes (E1-E5, L1,L2) to the HPV oncogenic genes E6 and E7 (termed the ImmunOnco Score) would predict clinical outcomes. Survival analysis of 70 University of Michigan patients showed low ImmunOnco Score is associated with tumor recurrence. Citation Format: Shiting Li, Shaomiao Xia, Maria Lawas, Tingting Qin, Bailey Grab, Nisha D'Silva, Laura Rozek, Maureen Sartor. HPV integration identifies emerging oncogenes and carcinogenic mechanisms, potentially indicating tumor recurrences [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 2280.

Abstract 2788: Immunological targeting of integrin β1high/β3high melanoma

Abstract We previously reported two integrin β4 (ITGB4)-targeted immunologic strategies, e.g., ITGB4 protein-pulsed dendritic cells (ITGB4-DC) for vaccination and adoptive transfer of anti-CD3/anti-ITGB4 bispecific antibody (ITGB4 BiAb)-armed tumor draining lymph node (TDLN) T cells. Both immunotherapies significantly demonstrated efficacy in inhibiting local tumor growth and lung metastases. We found these therapeutic efficacies were closely associated with the T cell as well as humoral anti-integrin β4high cancer stem cells (CSCs) in breast (4T1) and head and neck squamous cell carcinoma (SCC7) tumor models. Recently, we further found that integrin subunits β1 (ITGB1) and β3 (ITGB3) are expressed at significantly high level in melanoma cells. In culture cell lines, integrin β1 and β3 are highly expressed on approximately 98% and 95% of the two mouse melanoma cell lines F10 and D5. We confirmed the expression of these two integrin subunits in newly harvested fresh melanoma tumors in vivo, which is very similar to the findings in cell lines. We then assessed ITGB1 and/or ITGB3-pulsed dendritic cell (DC) vaccines using F10 mouse model and demonstrated that ITGB1-DC or ITGB3-DC vaccine both exhibited significant antitumor efficacy inhibiting tumor growth, and ITGB1-DC + ITGB3-DC showed an additive/synergistic anti-tumor effect. Notably, we found that ITGB1 and ITGB3 loaded on separate DCs demonstrated more potent antitumor efficacy than loaded on the same DCs as vaccine. In addition, anti-PD-L1 significantly augmented the antitumor efficacy of ITGB1-DC/ITGB3-DC vaccine to inhibit tumor growth. Considering the crucial role of CSCs in tumor initiation, progression, metastasis, and recurrence, we further evaluated the expression of ITGB1 and ITGB3 on F10 and D5 ALDHhigh CSCs. We detected significantly higher expression of ITGB1 on ALDHhigh F10 CSCs (83.3%) and ALDHhigh D5 CSCs (87.1%) vs. ALDHlow F10 non-CSCs (0.2%) and ALDHlow D5 non-CSCs (2.0%), suggesting that ITGB1 and ITGB3-targeted vaccine-conferred anti-melanoma effects may have significantly involved targeting of ITGB1high/ITGB3high melanoma CSCs. Furthermore, recent studies suggested that bone marrow (BM)-DCs expressing dysfunctional integrin β2 (ITGB2) exhibited more potent antigen presentation function than WT BM-DCs. We found that ITGB2 highly (63.3%) expressed on the surface of BM-DC, but not on F10 or D5 tumor cells. On-going experiments include the investigation of experimental evidence to verify that ITGB1 and ITGB3-targeted vaccines have induced targeting of ITGB1high/ITGB3high melanoma CSCs; and both the cellular and humoral mechanisms underlining the anti- ITGB1high/ITGB3high melanoma CSC immunity. At the same time, generation and use of ITGB2 deficient DCs for the vaccine preparation to improve the efficacy of DC vaccine targeting integrin ITGB1high/ITGB3high melanoma and melanoma CSCs warranty further investigation. Citation Format: Feng Wang, Ying Xin, James J. Moon, Alfred E. Chang, Max Wicha, Qiao Li. Immunological targeting of integrin β1high/β3high melanoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 2788.

Abstract 738: MBRC-101: a novel antibody-drug conjugate (ADC) targeting the tyrosine kinase receptor EphA5

Abstract Introduction: The receptor tyrosine kinase EphA5 has the classical receptor kinase topology with an extracellular-binding domain, a single-pass transmembrane domain, and a cytoplasmic kinase domain. Previously, EphA5 has been shown to contribute to DNA-damage repair and radiation therapy resistance in lung cancer. We investigated EphA5 expression in lung cancer as well as breast, pancreatic, gastric, and colorectal cancer and assessed its potential as a therapeutic target using a novel ADC, MBRC-101. Methods: MBRC-101 is composed of a humanized anti-EphA5 IgG1 monoclonal antibody conjugated to monomethyl auristatin E (MMAE) via a cleavable valine-citrulline linker using site-specific ThioBridge™ technology. The specificity profile of the anti-EphA5 antibody was characterized using a membrane proteome array. Receptor-mediated antibody internalization was determined by real-time live-cell analysis, and cell killing assays were performed using analysis of cell confluence and luminescent-based viability. Expression of EphA5 in archival human tissue sections was evaluated by immunohistochemistry (IHC) using a commercial antibody. Efficacy studies used patient-derived xenograft (PDX) models of lung adenocarcinoma, squamous cell carcinoma of both lung and head and neck, and breast cancer. Results: IHC demonstrated selective EphA5 membrane expression in 78% (18/23) of triple negative and 88% (23/26) of hormone receptor-positive breast cancer tumors tested. EphA5 membrane expression was also detected in 85% (29/34), 73% (16/22), 70% (7/10), 70% (15/22), and 50% (6/12) of lung squamous cell carcinoma, lung adenocarcinoma, gastric, colorectal, and pancreatic patient tumors tested, respectively. EphA5 expression was not detected in adjacent, non-malignant tissue in any of the tumors examined. The anti-EphA5 antibody bound exclusively to EphA5 and did not cross-react with other members of the Eph receptor/ephrin ligand family. Binding of the anti-EphA5 antibody on the cell surface triggered rapid internalization and processing through the endosomal-lysosomal system. MBRC-101 was cytotoxic to EphA5-expressing cells and its activity was concentration-dependent and commensurate to levels of EphA5 on the cell surface. In PDX models, once weekly administrations of intravenous MBRC-101 showed dose-dependent, robust, and reproducible anti-tumor activity. Partial tumor responses were observed at doses of 2.5 mg/Kg and complete tumor responses starting at 5 mg/Kg. Toxicologic findings in Sprague-Dawley rats and cynomolgus monkeys were attributed to the MMAE payload and not target-related. Based on an HNSTD of 10 mg/kg in monkeys, the starting human dose was 0.5 mg/kg with ~15-fold safety margin. Conclusions: EphA5 is a new and promising molecular target for the development of ADC-based therapies against many human cancers. A Phase 1/1b study of MBRC-101 is currently recruiting (NCT06014658). Citation Format: Fernanda I. Staquicini, Fenny H. Tang, Vanessa de Oliveira, Daniela I. Staquicini, Yongjian Wu, Kirstin F. Barnhart, J Kellogg Parsons, Wadih Arap, Isan Chen, Renata Pasqualini. MBRC-101: a novel antibody-drug conjugate (ADC) targeting the tyrosine kinase receptor EphA5 [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 738.

Abstract 1734: Dissecting the bifaceted function of SMYD3 as a transcriptional activator and repressor in HPV-negative HNSCC

Abstract Background: Approximately 75% of Human-papilloma-virus (HPV)-negative head and neck squamous cell carcinoma (HNSCC) tumors carry genetic and expression alterations in the family of protein methyltransferases and demethylases, underscoring the importance of these enzymes in the pathogenesis of HNSCC. SMYD3 a lysine methyltransferase that is overexpressed in HPV-negative HNSCC. We recently reported that nuclear SMYD3 plays dual role in immune-related gene regulation through H3K4me3 or H4K20me3, leading to gene activation or silencing, respectively in HPV-negative HNSCC. While SMYD3 has been reported to write and bind to H3K4me3 activating target gene expression, its function in gene silencing is understudied. This study aims to determine the mechanism(s) through which SMYD3 functions both as a transcriptional activator and a repressor within the same cell context, specifically in HPV-negative HNSCC. Methods: immunoprecipitation (IP) of SMYD3 was performed from nuclear extracts isolated from HN-6 cells to identify candidate interacting partners of SMYD3. The nuclear immunoprecipitates were sent for MS analysis to identify candidate nuclear interacting partners of SMYD3. CUT&RUN assays for selected candidate interacting proteins and SMYD3 will be performed in control HN-6 cells versus SMYD3 KO cells to assess genomic co-occupancy with SMYD3. Further, CUT&RUN assays for repressive marks H4K20me3, H3K27me3 and H3K9me3 have been performed in HN-6 and SMYD3 KO cells to assess co-occupancy with SMYD3 as well as its effect of SMYD3 on the genome-wide mapping of these marks. Finally, CUT&RUN assays for SMYD3 followed by re-CUT&RUN of repressive histone marks are ongoing to identify co-occupied loci. Results: Preliminary analysis of our nuclear SMYD3 IP results has identified a chromatin modifier with known repressive function. Co-immunoprecipitation experiments to validate this interaction are planned. CUT&RUN assays for repressive histone marks in HN-6 versus SMYD3 KO cells have revealed impact on H4K20me3 and H3K27me3. Conclusions: Our preliminary results suggest that SMYD3 may exert its silencing function by regulating the genome-wide deposition of H4K20me3.Our nuclear SMYD3 IP analysis has identified candidate interacting partners that may assist SMYD3 in promoting the deposition of these repressive marks. CUT&RUN assays for SMYD3 followed by re-CUT&RUN for H4K20me3 and H3K27me3 bound chromatin may provide further insight about whether SMYD3 co-occupies specific genomic regions together with these repressive marks. This project is expected to provide mechanistic insights into the bifaceted functions of SMYD3 within the same cell context using HPV-negative HNSCC cell lines as an experimental model system.. Citation Format: Jawad Akhtar, Sohyoung Kim, Vassiliki Saloura. Dissecting the bifaceted function of SMYD3 as a transcriptional activator and repressor in HPV-negative HNSCC [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 1734.

Abstract 5488: AI-enhanced spatial proteomics reveals B-cells & FoxP3+ cells interactions in HPV(+) oropharyngeal squamous cell carcinoma Progression

Abstract Background: Analyzing interactions and the microanatomical distribution of the tumor immune microenvironment (TIME) is essential for a comprehensive understanding of tumor progression. Imaging Mass Cytometry (IMC) is a high-dimensional tissue imaging system that enables the deeper and multiparametric in situ exploration of tumor microenvironments at a single-cell level. This study describes a pipeline for analyzing 39-plex IMC images of human HPV(+) oropharyngeal squamous cell carcinoma (OPSCC) tumor sections, elucidating immune cells' nature, functions, and interactions with tumor cells. The IMC data analysis provides valuable information for clinical studies that could be used for the identification of prognostic biomarkers and mechanisms of resistance to current immunotherapies. Methods: A retrospective study was conducted on (N=20) patients (10 progressors and 10 non-progressors) with HPV(+) OPSCC. The dataset comprises paired hematoxylin and eosin (H&E) images with IMC data from multiple Regions of Interest (ROIs) (N=82), enabling the in-situ profiling of 39 proteins in primary tumor tissue. Cell segmentation was followed by employing original images and their segmentation masks for cell phenotype identification using a probabilistic neural network method to spatially profile cancer cells, macrophages, NK-M cells, B-cells, and distinct T-cell populations. We identified protein expression at single-cell resolution and investigated the impact of multicellular spatial organization on the disease progression. The spatial neighborhood interaction score of tumor cells with various other cells was computed for all the ROIs across the two groups. Results: The markers showed varying expression levels of intensity distribution, likely due to differences in tissue sample composition. Specifically, CD3, CD4, CD8, CD19, CD20, and CD68 showed significantly higher intensity in non-progressors. Interestingly, FoxP3 also had a significantly higher intensity level in non-progressors. Cell phenotyping emphasized that non-progressors generally have increased levels of NK-M cell markers. Spatial analysis revealed a significant increase in interaction between CD3 cells and tumor cells in non-progressors (p-value=0.07, Mann-Whitney U test). Furthermore, a significant rise in the interaction between B-cells and FoxP3+ cells was observed in non-progressors (p-value<0.05, Mann-Whitney U test) suggesting a coordinated suppression of tumor growth. Conclusion: We developed a deep learning-based pipeline to analyze spatial relationships in the TIME of IMC data, demonstrating its clinical relevance in predicting disease progression. Our findings emphasize the importance of spatial relationships in the TME for response and suggest that proximity between either CD3+ T-cells to cancer cells or B-cells to FoxP3+ cells are candidate biomarkers. Citation Format: Sumanth Reddy Nakkireddy, Routman David, Kathleen Bartemes, Daniel Ma, Tae Hyun Hwang, Kathryn Van Abel, Chadi Nimeh Abdel-Halim. AI-enhanced spatial proteomics reveals B-cells & FoxP3+ cells interactions in HPV(+) oropharyngeal squamous cell carcinoma Progression [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 5488.

Abstract 4352: A high rate of episomal HPV16 is present in head and neck squamous cell carcinoma tumors by long-read whole genome sequencing

Abstract Persistent Human Papillomavirus (HPV) infection causes an increased risk of Head and Neck Squamous Cell Carcinoma (HNSCC). However, a comprehensive understanding of the intricate molecular events within virus-positive tumors remains a critical knowledge gap. Therefore, we used long-read sequencing to study the intricacies of HPV integration events within the genomic landscape of HPV+ HNSCC tumors. A total of 16 tissue biopsies, including 10 tumors and 6 matched adjacent normal tissues from histopathologically confirmed HNSCC subjects were sequenced by LSK114 chemistry of Oxford Nanopore Technology with an average coverage of 30X and 10X, respectively. The predicted mitochondrial haplotype from Mitomaster confirmed that the tumor/normal pair was from the same individual. The HPV integration status was determined by aligning fastq_pass files at the Cancer Genomics Cloud and viewing the breakpoints in the Integrated Genome Viewer. HPV lineage and sub-lineage classification was determined using ClustalOmega. We detected HPV16 in 8/10 tumors, with sublineages A1 and A2 accounting for 38% (3/8) and D3 for 25% (2/8). One tumor sample had a very low HPV load with only one HPV16 sequence read and low detection by PCR. Interestingly, we found that 5/8 HPV positive tumors had episomal HPV16 with different states. So, two tumors had intact HPV episomes, two more had either a small deletion or an insertion in the episomal HPV, and the last one had a rearranged episomal multimer (Table 1). The remaining three tumors had integrated HPV16: one with type 1 integrations at 11q12.13 and two others with type 2 integrations at chr1q42.12 and chr14q21.1. Our results indicate that episomal HPV16 is more prevalent than integrated HPV16 in primary HPV+ HNSCC samples. These findings provide new insights into the molecular mechanisms and consequences of HPV infection in HNSCC. Table 1: HPV characterization in HNSCC studied tissue biopsies. Patient ID Race HPV status HPV sublineages Predicted Haplotype HPV pattern #PID_1 Caucasian HPV16 + A2 T2b (T2b) Type 2 Integration (chr1q42.12) #PID_2 - HPV- - I1a (I1a1b) - #PID_3 Caucasian HPV16 + A1 H1q (H1q) Episomal (rearranged multimer) PID_4 African American HPV16 + A1 - Episomal (deletion of 636bp from 4892 to 5528) #PID_5 - HPV16 + A2 H1 (H1+16189) Type 1 Integration (complex chr11q12.13) *#PID_6 Caucasian HPV16 + - T2b (T2b) - PID_7 Caucasian HPV16 + D3 - Episomal #PID_8 African American HPV16 + D3 L1c (L1c3a) Type 2 Integration (chr14q21.1) PID_9 African American HPV16 + A2 - Episomal (insertion of 257bp from 7310-7567) PID_10 Caucasian HPV16 + A1 - Episomal *Very weakly HPV16 positive; #Tumor-normal pair Citation Format: Sonam Tulsyan, Vera Mukhina, Isabel Rodriguez, Subhendu R. Choudhury, Erin Allor, Kyle Hatte, Michael Dean, Daria A. Gaykalova. A high rate of episomal HPV16 is present in head and neck squamous cell carcinoma tumors by long-read whole genome sequencing [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 4352.

Abstract 4206: Regional transcriptomic profiling of the head and neck squamous cell carcinoma tumor microenvironment paired with murine models identify extracellular matrix components that mediate tumor progression and immune suppression

Abstract Purpose: A substantial contribution to the poor prognosis for head and neck squamous cell carcinoma (HNSCC) patients is the progression to distant metastasis. This occurs in 30% of patients over the course of their disease, and radically reduces the 5-year survival rate to under 50%. Investigations in recent years have begun to unveil the intricate interplay of the extracellular matrix (ECM) in both tumor-intrinsic signaling and immunoregulation. However, studies conducted in the context of metastatic have been limited. Here, we employ spatial transcriptomics on HNSCC patient biopsies to identify ECM components that may contribute to cancer progression and immune suppression. Experimental design: Comprehensive transcriptome profiling of HNSCC patient biopsies was conducted using the GeoMx Digital Spatial Profiler (DSP). This approach allowed us to characterize regions of the tumor microenvironment (TME) by immunofluorescent staining for subsequent bioinformatic analysis. To investigate the biological consequences of associations observed in our dataset, we performed in vivo murine studies. We have produced a series of SCC C57BL/6 murine cell lines derived from Smad4-/-KrasG12D Keratin15+ stem cells, which faithfully mimic the clinical progression of HNSCC tumors, including metastasis. Using these murine models, we applied relevant pharmacologic inhibitors and genetic knockdown of targets identified with our GeoMx DSP analysis. In vitro immune-based and functional assays were conducted to elucidate the underlying mechanisms contributing to SCC progression. Results: GeoMx DSP analysis revealed that laminins were enriched in stage IV HNSCC patient stroma, relative to lower stage patients. This coincided with TGFβ enrichment and inversely associated with signatures of anti-tumor immune infiltration. Analysis of The Cancer Genome Atlas data revealed similar inverse correlations in SCCs, distinct from breast cancer and lung adenocarcinoma. Our metastatic SCC murine lines likewise exhibited elevated levels of these laminin proteins, accompanied by high levels of laminin-binding integrins and TGFβ-Smad signaling. Independent of impacting cell proliferation, shRNA knockdown of laminin decreased tumor volume in an immune-competent setting. Targeting laminin-integrin signaling with the small molecule inhibitors Galunisertnib and Buparlisib also reduced the metastatic capacity of these cells in C57BL/6 mice. Conclusions: Spatial transcriptomic profiling of the HNSCC TME uncovers intricate associations and promising targets not readily discernible in bulk RNAseq analyses. Validation through genetic and pharmacological approaches in immune-competent models underscores their potential as strategies to reduce HNSCC burden. Citation Format: John D. Aleman, Khoa A. Nguyen, Erica Wong, Yao Ke, Hanne T. Lind, Clifford G. Tepper, Andrew C. Birkeland, Christian D. Young, Sana D. Karam, Xiao-Jing Wang. Regional transcriptomic profiling of the head and neck squamous cell carcinoma tumor microenvironment paired with murine models identify extracellular matrix components that mediate tumor progression and immune suppression [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 4206.

Cytoprotective role of human dental pulp stem cell-conditioned medium in chemotherapy-induced alopecia

BackgroundChemotherapy-induced alopecia (CIA) is a distressing adverse effect of chemotherapy, with an estimated incidence of 65% and limited treatment options. Cyclophosphamide (CYP) is a common alopecia-inducing chemotherapy agent. Human dental pulp stem cells (DPSCs) secrete several paracrine factors that up-regulate hair growth. Conditioned medium (CM) collected from DPSCs (DPSC-CM) promotes hair growth; culturing mesenchymal stem cells under hypoxic conditions can enhance this effect.MethodsThe effect of DPSC-CM cultured under normoxic (N-) and hypoxic (H-) conditions against CYP-mediated cytotoxicity in keratinocytes was examined using cell viability assay, lactate dehydrogenase (LDH) cytotoxicity assay, and apoptosis detection. The damage-response pathway was determined in a well-established CIA mouse model by analyzing macroscopic effects, histology, and apoptosis. Reverse transcription-quantitative PCR and Caspase-3/7 activity assay were used to investigate the impact of DPSC-CM on the molecular damage-response pathways in CYP-treated mice. The effect of post-CIA DPSC-CM application on post-CIA hair regrowth was analyzed by macroscopic effects and microstructure observation of the hair surface. Furthermore, to investigate the safety of DPSC-CM as a viable treatment option, the effect of DPSC-CM on carcinoma cell lines was examined by cell viability assay and a subcutaneous tumor model.ResultsIn the cell viability assay, DPSC-CM was observed to increase the number of keratinocytes over varying CYP concentrations. Furthermore, it reduced the LDH activity level and suppressed apoptosis in CYP-treated keratinocytes. DPSC-CM exhibited the cytoprotective role in vivo via the dystrophic anagen damage-response pathway. While both N-CM and H-CM downregulated the Caspase-3/7 activity level, H-CM downregulated Caspase-3 mRNA expression. The proportion of post-CIA H-CM-treated mice with > 90% normal hair was nearly twice that of vehicle- or N-CM-treated mice between days 50 and 59 post-depilation, suggesting that post-CIA H-CM application may accelerate hair regrowth and improve hair quality. Furthermore, DPSC-CM suppressed proliferation in vitro in certain carcinoma cell lines and did not promote the squamous cell carcinoma (SCC-VII) tumor growth rate in mice.ConclusionsThe potentiality of DPSC-CM and H-CM as a promising cytoprotective agent and hair regrowth stimulant, respectively, for CIA needs in-depth exploration.

FGFR2 and miR-889-3p expression in oral cancer is associated with cervical lymph node metastasis.

Fibroblast growth factor receptor-2 (FGFR2) and miR-889-3p expression in oral squamous cell carcinoma (OSCC) tumours were compared to normal controls. We then examined the relationship between miR-889-3p, FGFR2 expression and patient clinicopathological features. The interaction of FGFR2 and miR-889-3p was investigated using bioinformatics. Then, OSCC tumour biopsies and normal gingiva were collected and processed for expression analysis of FGFR2-specific mRNA and miR-889-3p using real-time PCR. Immunohistochemistry evaluated the expression of the FGFR2 protein. The protein and mRNA expression levels of FGFR2 were significantly greater in tumours when contrasted with controls. Expression of miR-889-3p was significantly lower in OSCC compared to normal tissues. The FGFR2 and miR-889-3p expressions were inversely related (-0.86 and -0.73, respectively) in both cases and controls. Changes in miR-889-3p and FGFR2 expression in tumour tissues were associated with lymph node metastasis (LNM), with ~0.57 and ~3.0 folds of change in positive-LNM patients, respectively. Decreased expression of miR-889-3p in OSCC tumours suggests that miR-889-3p functions as a tumour suppressor gene. Overexpression of FGFR2 further proves the role of miR-889-3p in the regulation of the FGFR2 pathway. This was further confirmed by showing differences in miR-889-3p expression in positive and negative LNM cases.

Integrating the 40-Gene Expression Profile (40-GEP) Test Improves Metastatic Risk-Stratification Within Clinically Relevant Subgroups of High-Risk Cutaneous Squamous Cell Carcinoma (cSCC) Patients.

The validated 40-gene expression profile (40-GEP) test independently stratifies risk of regional or distant metastasis for cutaneous squamous cell carcinoma (cSCC) tumors with high-risk clinicopathologic features. This study evaluated the stratification of risk by the 40-GEP test in a large cohort of tumors with one or more high-risk factors and in clinically relevant subgroups, including tumors within National Comprehensive Cancer Network (NCCN) high- and very-high-risk groups, lower-stage BWH T1 and T2a tumors, and patients > 65years old. This multicenter (n = 58) performance study of the 40-GEP included 897 patients. Kaplan-Meier analyses were performed to assess risk stratification profiles for 40-GEP Class 1 (low), Class 2A (higher) and Class 2B (highest) risk groups, while nested Cox regression models were used to compare risk prediction of clinicopathologic risk classification systems versus risk classification systems in combination with 40-GEP. Patients classified as 40-GEP Class 1, Class 2A, or Class 2B had significantly different metastatic risk profiles (p < 0.0001). Integrating 40-GEP results into models with individual clinicopathologic risk factors or risk classification systems (Brigham and Women's Hospital, American Joint Committee on Cancer Staging Manual, 8th Edition) and NCCN demonstrated significant improvement in accuracy for prediction of metastatic events (ANOVA for model deviance, p < 0.0001 for all models). The 40-GEP test demonstrates accurate, independent, clinically actionable stratification of metastatic risk and improves predictive accuracy when integrated into risk classification systems. The improved accuracy of risk assessment when including tumor biology via the 40-GEP test ensures more risk-aligned, personalized patient management decisions.

DDX3 regulates cancer immune surveillance via 3′ UTR-mediated cell-surface expression of PD-L1

Programmed death-1 (PD-1)/PD ligand-1 (PD-L1)-mediated immune escape contributes to cancer development and has been targeted as an anti-cancer strategy. Here, we show that inhibition of the RNA helicase DDX3 increased CD8+ Tcell infiltration in syngeneic oral squamous cell carcinoma tumors. DDX3 knockdown compromised interferon-γ-induced PD-L1 expression and, in particular, reduced the level of cell-surface PD-L1. DDX3 promoted surface PD-L1 expression by recruiting the adaptor protein 2 (AP2) complex to the 3' UTR of PD-L1 mRNA. DDX3 depletion or 3' UTR truncation increased the binding of the coatomer protein complexes to PD-L1, leading to its intracellular accumulation. Therefore, this 3' UTR-dependent mechanism may counteract cellular negative effects on surface trafficking of PD-L1. Finally, pharmaceutic disruption of DDX3's interaction with AP2 reduced surface PD-L1 expression, supporting that the DDX3-AP2 pathway routes PD-L1 to the cell surface. Targeting DDX3 to modulate surface trafficking of immune checkpoint proteins may provide a potential strategy for cancer immunotherapy.

Analysis of HLA-G 14 bp Insertion/Deletion Polymorphism and HLA-G, ILT2 and ILT4 Expression in Head and Neck Squamous Cell Carcinoma Patients.

HLA-G is the checkpoint molecule involved in the suppression of the immune response. Increased expression of HLA-G and its ILTs receptors have been correlated with tumor progression in various cancer types. In head and neck squamous cell carcinoma (HNSCC) tumors, the effect of HLA-G, ILT2 and ILT4 expression on cancer development has to be explained. The 34 HNSCC patients and 98 controls were genotyped for the HLA-G 14 bp ins/del polymorphism. In HNSCC lesions, HLA-G, ILT2 and ILT4 mRNA expression was analysed using real-time PCR. The association between HLA-G, ILT2 and ILT4 mRNA expression and clinical variables (age at onset, TNM staging system and p16 positivity) was also evaluated. No genetic association between the HLA-G 14 bp ins/del and HNSCC risk was detected (p > 0.05). However, in the non-metastatic HNSCC group, a significantly higher HLA-G mRNA expression was noted in tumors in the T4 stage compared to those in the T1 and T2 stages (p = 0.0289). ILT2 mRNA expression was significantly increased in non-metastatic vs. metastatic tumors (p = 0.0269). Furthermore, a significantly higher ILT4 mRNA expression was noted in tumors in the T1+T2 stage compared to those in the T3 stage (p = 0.0495). Our results suggest that the HLA-G molecule creates an immunological microenvironment involved in HNSCC development.

Postoperative Radiotherapy and Survival in Oral Cavity Squamous Cell Carcinoma With Mandibulectomy

Oral cavity squamous cell carcinoma (SCC) tumors with mandibular invasion are upstaged to pT4a regardless of their size. Even small tumors with boney invasion, which would otherwise be classified as pT1-2, are recommended for the locally advanced treatment pathway to receive administration of postoperative radiotherapy (PORT). To evaluate the association of PORT with overall survival according to tumor size among patients who received mandibulectomy for pT4aN0 oral cavity SCC. This was a retrospective analysis using data from the US National Cancer Database from January 1, 2004, through December 31, 2019. All patients who received mandibulectomy for treatment-naive pT4aN0 oral cavity SCC with negative surgical margins were included. Data analyses were performed in January 2023 and finalized in July 2023. PORT vs no PORT. Entropy balancing was used to balance covariate moments between treatment groups. Weighted multivariable Cox proportional hazards regression was used to measure the association of PORT with overall survival associated with tumor size. Among 3268 patients with pT4aN0 oral cavity SCC (mean [SD] age, 65.9 [12.1] years; 2024 [61.9%] male and 1244 [38.1%] female), 1851 (56.6%) received PORT and 1417 (43.4%) did not receive PORT. On multivariable analysis was adjusted for age, insurance status, Charlson Comorbidity Index score, tumor site, tumor grade, tumor size, and PORT. Findings indicated that PORT was associated with improved overall survival and that this relative survival advantage trended upwards with increasing tumor size. That is, the larger the tumor, the greater the survival advantage associated with the use of PORT. For the 1068 patients with tumors greater than 4 cm, the adjusted hazard ratio (aHR) in favor of PORT was 0.63 (95% CI, 0.48-0.82); for the 1774 patients with tumors greater than 2 cm but less than or equal to 4 cm, the aHR was 0.76 (95% CI, 0.62-0.93); and for 426 patients with tumors less than 2 cm, the aHR was 0.81 (95% CI, 0.57-1.15). In this retrospective analysis of patients who received mandibulectomy for pT4aN0 oral cavity SCC, PORT was associated with improved overall survival, the benefit of which improved relatively with increasing tumor size. These findings suggest that tumor size should be considered in guidelines for PORT administration in this patient population.

Amlodipine inhibits the proliferation and migration of esophageal carcinoma cells through the induction of endoplasmic reticulum stress.

L-type calcium channels are the only protein channels sensitive to calcium channel blockers, and are expressed in various cancer types. The Cancer Genome Atlas database shows that the mRNA levels of multiple L-type calcium channel subunits in esophageal squamous cell carcinoma tumor tissue are significantly higher than those in normal esophageal epithelial tissue. Therefore, we hypothesized that amlodipine, a long-acting dihydropyridine L-type calcium channel blocker, may inhibit the occurrence and development of esophageal cancer (EC). To investigate the inhibitory effects of amlodipine on EC through endoplasmic reticulum (ER) stress. Cav1.3 protein expression levels in 50 pairs of EC tissues and corresponding paracancerous tissues were examined. Subsequently, the inhibitory effects of amlodipine on proliferation and migration of EC cells in vitro were detected using 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide and Transwell assays. In vivo experiments were performed using murine xenograft model. To elucidate the underlying mechanisms, in vitro cell studies were performed to confirm that ER stress plays a role in inhibition proliferation and migration of EC cells treated with amlodipine. The expression level of Cav1.3 in esophageal carcinoma was 1.6 times higher than that in paracancerous tissues. Amlodipine treatment decreased the viability of esophageal carcinoma cells in a dose- and time-dependent manner. In vivo animal experiments also clearly indicated that amlodipine inhibited the growth of EC tumors in mice. Additionally, amlodipine reduces the migration of tumor cells by inhibiting epithelial-mesenchymal transition (EMT). Mechanistic studies have demonstrated that amlodipine induces ER stress-mediated apoptosis and suppresses EMT. Moreover, amlodipine-induced autophagy was characterized by an increase in autophagy lysosomes and the accumulation of light chain 3B protein. The combination of amlodipine with the ER stress inhibitor 4-phenylbutyric acid further confirmed the role of the ER stress response in amlodipine-induced apoptosis, EMT, and autophagy. Furthermore, blocking autophagy increases the ratio of apoptosis and migration. Collectively, we demonstrate for the first time that amlodipine promotes apoptosis, induces autophagy, and inhibits migration through ER stress, thereby exerting anti-tumor effects in EC.