Head and neck mucosal melanoma: radiological considerations and UK imaging guidelines

PURPOSE

Awareness of head and neck mucosal melanoma (HNMM) is important, as incorrect work-up can impact on the investigation and management of this rare and aggressive cancer. Following on from the 2020 HNMM UK guidelines, we set out the imaging recommendations and their rationale. To illustrate the key imaging characteristics, we also include a case series from our centre.

METHODS

All HNMM cases managed at our institution from January 2016 to January 2021 were identified, and the available imaging for each patient was reviewed. For each patient, the age, gender and location of primary tumour was recorded together with key staging and diagnostic imaging parameters.

RESULTS

A total of 14 patients were identified. The median age was 65 years with a female to male ratio of 1.33:1. Primary tumours were sinonasal in location in 93% of cases, with 7% of patients having metastatic neck nodes at presentation and 21% of cases having distant metastatic disease at presentation.

CONCLUSION

This data set is in general concordance with other published series regarding the sinonasal origin of the vast majority of HNMM tumours along with the proportion of patients with metastatic neck nodes and distant metastases at presentation. We recommend dual-modality imaging with computed tomography (CT) and magnetic resonance imaging (MRI) of primary tumours whenever possible. In the systematic staging of HNMM, positron emission tomography (PET)-CT should be strongly considered, together with MRI of the brain. Pre-biopsy imaging of HNMM tumours is advisable whenever possible.

Gene of the month: cancer testis antigen gene 1b (NY-ESO-1)

Cancer testis antigen gene 1B (CTAG1B) and its associated gene product; New York oesophageal squamous carcinoma 1 (NY-ESO-1), represent a unique and promising target for cancer immunotherapy. As a member of the cancer testis antigen family (CTA), the protein's restricted expression pattern and ability to elicit spontaneous humoural and cellular immune responses has resulted in a plethora of novel modalities and approaches attempting to harness its immunotherapeutic anti-cancer potential. Here, we discuss the structure and function of CTAG1B/NY-ESO-1 in both health and disease, immunohistochemical detection, as well as the most promising advances in the development of associated anti-cancer therapies. From cancer vaccines to engineered cellular therapy approaches, a multitude of immunotherapies targeting CTA's are coming to the forefront of oncology. Although the efficacy of such approaches have yet to provide convincing evidence of durable response, early phase clinical trial data has resulted in some exciting findings which will have significant potential to act as a platform for future practice changing technologies.

Abstract 6132: Impact of treatment with agents targeting different members of HER family, CDKs and downstream cell signaling molecules on growth and migration of stomach cancer cells

Stomach cancer ranks fifth and fourth for the incidence and mortality rate for cancer worldwide, respectively. In recent years, several inhibitors with specificity to one or more members of human epidermal growth factor receptor (HER) family have been approved for the treatment of patients with different cancer types. Of these, only the anti-HER2 monoclonal antibody (mAb) Herceptin/trastuzumab and the antibody-drug conjugate trastuzumab deruxtecan has been approved for the treatment of patients with stomach cancer. However, the duration of response may be short in many patients and with tumor heterogeneity being one contributing factor. In this study, we investigated the effect of various types of targeted agents on the growth in vitro of a panel of human stomach cancer cells (HSCCLs) and the impact of stomach cancer proliferation rate on the anti-tumor activities of these agents. Moreover, we investigated the cell surface expression of the HER family members, other biomarkers such as C-Met, Alk-7 and cancer stem cell makers CD44 and CD133 by flow cytometry and the effect various targeted agents on tumor migration using Incucyte. Of the 18 agents examined, the CDK 1/2/5/9 inhibitor dinaciclib was the most effective and inhibited the growth of all human HSCCLs at IC50 values between 1nM to 9nM. Of various HER inhibitors, the irreversible pan-HER family inhibitors (e.g., afatinib) were more effective than the reversible dual EGFR/HER2 TKI lapatinib and the EGFR specific TKI erlotinib in inhibiting the growth of HSCCLs. Interestingly, the HER-2 overexpressing cells lines NCI-N87 (Mean Fluorescence Intensity =596) was most sensitive to the HER inhibitors. Of agents targeting different downstream cell signaling molecules, dasatinib targeting Ab1/Src/C-Kit, trametinib targeting MERK1/2 and miransertib targeting AKT1/2/3 inhibited growth of majority of HSCCLs and with the IC50 values ranging from 2nM to 7uM. Interestingly, many of these agents were more effective in inhibiting the growth of HSCCLs when proliferating at slower rate. Of the agent examined, neratinib, afatinib, dinacicilib, dasatinib, stattic and miransertib also inhibited the migration of stomach cancer cells. Finally, treatment with a combination of afatinib with dinaciclib, capmatinib, dasatinib, stattic, ponatinib or miransertib resulted in synergistic and additive growth inhibition of stomach cancer cells. As stomach cancer cells are heterogenous in nature, our results support further research on the therapeutic potential of the CDK dinaciclib in combination with a pan-HER inhibitor in stomach cancer.

Citation Format: Tina Al-Janaby, Narmin Nahi, Said A. Khelwatty, Alan Seddon, Izhar Bagwan, Helmout Modjtahedi. Impact of treatment with agents targeting different members of HER family, CDKs and downstream cell signaling molecules on growth and migration of stomach cancer cells. [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 6132.

Abstract 2691: Expression pattern and prognostic significance of HER family members and EGFRvIII in pancreatic cancer

Pancreatic cancer is one of the most aggressive, heterogeneous, and fatal types of human cancers. There is urgent need for discovery of biomarkers of prognostic significance, predictive value and as well as therapeutic targets in patients with pancreatic cancer. In this study, we examined the relative expression and prognostic significance of all HER family members and the type III EGFR mutant (EGFRvIII) in patients with pancreatic ductal adenocarcinoma (PDC). The expression levels of wild-type EGFR (wtEGFR), HER2, HER3, HER4 and EGFRvIII were determined in tumor specimens from 43 patients by immunohistochemistry using antibodies DAK-H1-WT, Neu 3B5, SP71, HFR1 and NBP2-50599 respectively. The staining was scored based on the percentage of positive tumor cells, the intensity (i.e. strong 3+, moderate 2+, weak 1+) and the cellular location of immunostaining (i.e. membranous, cytoplasmic or nuclear). The association between the expression level of the biomarkers and patient overall survival was evaluated using Chi-squared, Kaplan-Meier survival curves and log rank test. At cut-off value of above 5%, we found weak to moderate expression of wtEGFR, HER2, HER3, HER4 and EGFRvIII in 4.7%, 14%, 14%, 20.9% and 2.3% of the cases examined respectively. The cellular location of wtEGFR and HER2 was found to be predominantly cytoplasmic, HER-3 membranous and cytoplasmic whereas HER4 expression was found to be mainly nuclear. There was no statistically significant association between the expression level of these markers and patient overall survival. The expression levels of the above biomarkers were also evaluated in tissue microarrays (TMAs) from 40 cases of pancreatic ductal adenocarcinoma. Interestingly, at the same cut-off value, 62.5%, 75%, 0%, 55% and 5% of the TMAs were positive for wtEGFR, HER2, HER3, HER4 and EGFRvIII respectively. Overall, we found that the expression pattern of HER family members was heterogenous, and with EGFRvIII expression being very low in both whole tumor sections and TMAs from patients with pancreatic cancer. Taken together, our results provide support for more detailed studies of co-expression of all HER family members in a larger group of pancreatic cancer patients. Such studies should help to unravel their potential as targets for therapeutic interventions as well as their prognostic significance and predictive value for response to therapy.

Citation Format: Tanzeel Khan, Said A. Khelwatty, Izhar Bagwan, Alan Seddon, Angus Dalgleish, Satvinder Mudan, Helmout Modjtahedi. Expression pattern and prognostic significance of HER family members and EGFRvIII in pancreatic cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 2691.

Well Differentiated Liposarcoma Presenting as a Duodenal Polyp: A Case Report and Review of the Literature

Liposarcoma is the most common malignant soft tissue tumour in adults occurring predominantly in the retroperitoneum and extremities but very rarely within the gastrointestinal tract. We report on a 77-year-old gentleman who presented with a history of melaena and anaemia. On oesophagogastric duodenoscopy a duodenal polyp was identified. Surgical excision was performed and on histology, the duodenal polyp revealed a primary duodenal well differentiated liposarcoma. A literature review confirmed the rarity of primary duodenal liposarcomas, with only four cases previously reported.

HOX and PBX gene dysregulation as a therapeutic target in glioblastoma multiforme

BACKGROUND

Glioblastoma multiforme (GBM) is the most common high-grade malignant brain tumour in adults and arises from the glial cells in the brain. The prognosis of treated GBM remains very poor with 5-year survival rates of 5%, a figure which has not improved over the last few decades. Currently, there is a modest 14-month overall median survival in patients undergoing maximum safe resection plus adjuvant chemoradiotherapy. HOX gene dysregulation is now a widely recognised feature of many malignancies.

METHODS

In this study we have focused on HOX gene dysregulation in GBM as a potential therapeutic target in a disease with high unmet need.

RESULTS

We show significant dysregulation of these developmentally crucial genes and specifically that HOX genes A9, A10, C4 and D9 are strong candidates for biomarkers and treatment targets for GBM and GBM cancer stem cells. We evaluated a next generation therapeutic peptide, HTL-001, capable of targeting HOX gene over-expression in GBM by disrupting the interaction between HOX proteins and their co-factor, PBX. HTL-001 induced both caspase-dependent and -independent apoptosis in GBM cell lines.

CONCLUSION

In vivo biodistribution studies confirmed that the peptide was able to cross the blood brain barrier. Systemic delivery of HTL-001 resulted in improved control of subcutaneous murine and human xenograft tumours and improved survival in a murine orthotopic model.

Frontal sinus infection leading to sino-orbital aspergillosis: a case report

Sino-orbital aspergillosis is an uncommon but aggressive infection. It rarely originates from the frontal sinus due to the complex anatomy of the frontal recess and anteromedial position of its ostium. An 87-year-old man of Nigerian heritage with a history of multiple myeloma, chronic kidney disease and type 2 diabetes, presented to the eye clinic with a right tense swollen eyelid and proptosis. Computed tomography (CT) and magnetic resonance imaging (MRI) scan revealed a right superomedial mass communicating with the frontal sinus and biopsy confirmed an orbital aspergilloma. The patient was successfully treated with debulking surgery and anti-fungal treatment despite developing side effects to the drugs. To improve prognosis, ophthalmologists should be aware of this distinct entity and use a multi-disciplinary approach.

O-OGC07 Endoscopically derived oesophageal adenocarcinoma organoids to assess potential response to neo-adjuvant therapy and virotherapy

Background

Organoids are 3D models that retain the architecture and function of the organ from which they are derived. Culture of oesophageal adenocarcinoma organoids from individual’s standard endoscopic biopsies to assess response to therapy could dramatically alter the neo-adjuvant treatment paradigm, giving clarity over who will benefit from therapy, including novel treatment methodologies. Immune checkpoint blockade (ICB) has been shown to be effective in oesophageal adenocarcinoma. Combining Oncolytic Virotherapy with ICB could enhance the action of ICB alone, through selective infection of tumour cells accompanied by immunogenic cell death, with release of neo-tumour antigens and alteration of the tumour microenvironment.

Methods

This study uses organoids derived from endoscopic biopsies to assess the viability of an oncolytic herpes simplex virus in the treatment of oesophageal adenocarcinoma. Samples were taken at staging endoscopy using standard biopsy forceps. Tissue specimens were dissociated using the Miltenyi tumour dissociation kit before being suspended in Matrigel in conditioned media. Media was changed every 48 hours with domes being split every 7-10 days. After >6 passages organoids were incubated with an oncolytic herpes simplex virus lacking ICP 34.5 and 47. Growth was monitored, and green fluorescence protein expression measured using the Incucyte SX5 Live Cell Analysis system.

Results

Organoids were successfully established and cultured beyond 6 passages for patients with oesophageal adenocarcinoma. Organoids incubated with an oncolytic herpes simplex virus demonstrated significantly reduced growth compared to untreated organoids with increased expression of green fluorescence protein indicating viral infection.

Conclusions

We have demonstrated a successful methodology to culture Oesophageal adenocarcinoma organoids from endoscopic biopsies. Further work to determine their responses to standard chemotherapy used in the perioperative phase will help to assess their potential for providing bespoke therapy in the future. Oncolytic herpes simplex virus is able to infect and cause lysis of OAC organoids supporting its potential use in driving an increased inflammatory tumour microenvironment which could be combined with immune checkpoint blockade to induce durable responses for patients.

Moy.01HOXB9: an emerging novel prognostic marker and potential target for gene-therapy in colorectal liver metastases

Aims

Homeobox (HOX) proteins are emerging as promising biomarkers and targets for gene-therapy in cancer; however, their role in colorectal liver metastases (CRLM) is unknown. This study aims to investigate the role of HOXB9 as prognostic marker and potential therapeutic target in CRLM.

Methods

Two patient-cohorts were included: a) Patients with colorectal cancer (CRC) from the National Cancer Institute, Tissue Cancer Genome Atlas (TCGA) database (n = 614) and b) Institutional patient cohort who underwent liver resection for CRLM (n = 110) between 2007-2014. Primary outcome was 10-year overall survival (OS). COX regression and Kaplan-Meier survival analyses were performed including HOXB9 expression, demographics, clinicopathological and treatment-related variables. HOXB9 gene expression was modulated to assess its impact on CRC cell growth in vitro. Therefore, we conducted experimental studies using plasmid-vector and siRNA-interference to overexpress and knockdown HOXB9 respectively.

Results

Univariable TCGA analysis showed that HOXB9 did not predispose to poor OS (HR = 1, 95%CI:0.92-1.1, p = 0.620). On the contrary, univariable analysis in the CRLM patient cohort showed that high HOXB9 levels, right sided CRC, CRLM number≥4, CRLM diameter≥5cm, and intrahepatic recurrence were associated with significantly increased risk for worse OS. On multivariable models, only high HOXB9 expression (HR = 3.82, 95%CI:1.59-9.2, p = 0.003) and intrahepatic recurrence (HR = 4.28, 95%CI:1.88-9.72, p = 0.001) retained significance as independent prognostic factors after liver resection. Experimental studies showed that HOXB9 overexpression increased cell proliferation (p < 0.001) whereas HOXB9 inhibition markedly supressed CRC cell growth (p < 0.001) in vitro.

Conclusions

HOXB9 demonstrates oncogenic properties and may serve as novel prognostic marker and potential target for gene-directed therapy in CRC/CRLM.

SP1.1.7PBX4 functions as a novel oncogene and promotes angiogenesis in colorectal cancer: A comprehensive analysis of the PBX gene family

Aims

Pre-B-cell Leukaemia (PBX) genes are important in organ development during embryogenesis. To date, four members of the PBX family (PBX1, PBX2, PBX3, PBX4) have been identified to be involved in human cancers, but little is known about their role in colorectal cancer (CRC). The aim of this study was to determine their differential expression, prognostic role and function in CRC.

Methods

Molecular and overall survival (OS) data from 614 patients with CRC were obtained from the National Cancer Institute, Tissue Cancer Genome Atlas (TCGA) database. To investigate the differential PBX gene mRNA expression, we performed a comparative cancer to normal computational analysis in edgeR. To determine PBXs prognostic value, we conducted Kaplan-Meier survival analysis and COX regression, selecting 10-year OS as primary outcome. Lastly, to explore the effect of PBX4 in CRC cell growth and angiogenesis, we performed gene expression modulation experiments using a PBX4-overexpressing plasmid-vector. Cell proliferation and VEGFA angiogenic factor expression were defined as primary and secondary in vitro outcomes respectively.

Results

Among PBXs only PBX4 was significantly upregulated showing a 4-fold increase in CRC vs normal colon (p < 0.0001). Survival analysis showed that only high PBX4 mRNA expression was associated with increased risk for worse OS in patients with CRC (HR:1.3 95%CI:1-1.6, p = 0.02). Functionally, overexpression of PBX4 significantly increased CRC cell proliferation in vitro (p < 0.001) and markedly upregulated the expression of VEGFA (p < 0.0001).

Conclusions

Comprehensive analysis of the PBX gene family identifies that PBX4 may function as a novel oncogene and may promote angiogenesis through VEGFA in CRC.

What is the role of the surgeon in the management of head and neck mucosal melanoma in the immunotherapy era?

INTRODUCTION

The advent of immunotherapy has impacted both the management and, to a lesser extent, the outcomes for patients with head and neck mucosal melanoma. As a consequence, one might expect that the role of the surgeon would be limited to the diagnostic work-up and that systemic therapies would be the mainstay of treatment.

METHODS AND RESULTS

Here, we present the surgical aspects of the recently published United Kingdom Head and Neck Mucosal Melanoma Guideline to highlight the continued role of surgeons in the management of this disease. We highlight key areas where surgeons remain the lead clinician and reinforce the multidisciplinary requirement for exemplary patient care.

CONCLUSIONS

Despite the advent of immunotherapy, surgeons continue to have a key role to play in this disease. When indicated, it is essential that appropriate surgery is offered by a suitably experienced team.

Abstract 350: Co-expression and predictive value of HER family members for the response to therapy with cetuximab in patients with metastatic colorectal cancer

Background: Overexpression of the EGFR is common in patients with a wide range of cancers and the EGFR is an important target for therapy with monoclonal antibodies (mAbs) based drugs. Of these, cetuximab and panitumumab have been approved for the treatment of patients with metastatic colorectal cancer (mCRC). However, therapeutic benefits are seen in a subset of such patients and the duration of response can also be short. Indeed, there is currently no reliable predictive biomarkers for the selection of patients who benefit from therapy with the anti-EGFR antibodies. While KRAS mutation is currently used as an important negative predictive biomarker for the response to therapy with anti-EGFR mAbs, not all patients with wild type KRAS gain benefit from therapy with anti-EGFR mAbs and objective responses have been reported in mCRC patients with KRAS mutations.

Aim: The aim of this study was to investigate the predictive value of EGFR and its dimerization partner (i.e. all other members of the HER family) for the response to treatment with cetuximab in patients with wild-type KRAS status mCRC.

Methods: Using immunohistochemistry (IHC) we investigated the co-expression and predictive value of all four members of the HER family, for the response to cetuximab in 144 mCRC patients and in 21 paired primary tumours and their metastatic sites.

Results: Co-expression of all four members of the HER family were found in 10% of the cases examined. The expression of wtEGFR was an indicator of poorer overall survival and the membranous expression of HER2 and HER3 3+ intensity was associated with a shorter progression free survival (PFS). In contrast, the cytoplasmic expression of HER2 was associated with better PFS. In 48% and 71% of the cases examined, there were discordance in the expression of EGFR or one or more HER family members in paired primary and related metastatic tumours, respectively.

Conclusion: Our results implicate the importance of large prospective investigation of the expression level and predictive value of not only the therapeutic target (i.e. EGFR protein) but also its dimerization partners for the response to therapy with anti-EGFR mAbs and other forms of HER inhibitors in both the primary tumours and metastatic sites in colorectal cancer.

Citation Format: Said A. Khelwatty, Soozana Puvanenthiran, Sharadah Essapen, Izhar Bagwan, Alan M. Seddon, Helmout Modjtahedi. Co-expression and predictive value of HER family members for the response to therapy with cetuximab in patients with metastatic colorectal cancer [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 350.

Schwannoma of the sinonasal tract: case report with review of the literature

Schwannomas of the sinonasal tract are rare, accounting for <4% of head and neck schwannomas. We report the case of a 61-year-old male who presented with unilateral nasal symptoms. Examination and imaging revealed a unilateral polyp at the level of the middle turbinate, with an initial biopsy suggestive of an inflammatory polyp. Due to the persistence of the patient's symptoms and his polyp despite medical therapy, endoscopic nasal polypectomy was performed. The histology surprisingly showed a schwannoma. No further interventions were carried out, and the patient remains disease-free 6 months postoperatively. A review of the literature comprising 60 cases is included. An optimal clinical approach to the investigation and management of schwannomas of the sinonasal tract is subsequently discussed.

Head and neck mucosal melanoma: The United Kingdom national guidelines

The United Kingdom head and neck mucosal melanoma guideline development group used an evidence-based systematic approach to make recommendations in key areas of uncertainty in the field, including accurate diagnosis and staging; the appropriate treatment pathway including surgery, adjuvant radiation and new systemic treatments, such as targeted agents and immunotherapy; and the surveillance of patients after treatment. The guidelines were sent for international peer review and have been accredited by the National Institute for Health and Care Excellence. A summary of key recommendations is presented. The full documents are available on the Melanoma Focus website (https://melanomafocus.com/activities/mucosal-guidelines/mucosal-melanoma-resources/).

Ano-uro-genital mucosal melanoma UK national guidelines

Ano-uro-genital (AUG) mucosal melanomas are rare cancers associated with poor outcomes and limited evidence-based management. The United Kingdom AUG mucosal melanoma guideline development group used an evidence-based systematic approach to make recommendations regarding the diagnosis, treatment and surveillance of patients diagnosed with AUG mucosal melanomas. The guidelines were sent for international peer review, and are accredited by The National Institute for Health and Clinical Excellence (NICE). A summary of the key recommendations is presented. The full documents are available on the Melanoma Focus website.

Development and application of two novel monoclonal antibodies against overexpressed CD26 and integrin α3 in human pancreatic cancer

Monoclonal antibody (mAb) technology is an excellent tool for the discovery of overexpressed cell surface tumour antigens and the development of targeting agents. Here, we report the development of two novel mAbs against CFPAC-1 human pancreatic cancer cells. Using ELISA, flow cytometry, immunoprecipitation, mass spectrometry, Western blot and immunohistochemistry, we found that the target antigens recognised by the two novel mAbs KU44.22B and KU44.13A, are integrin α3 and CD26 respectively, with high levels of expression in human pancreatic and other cancer cell lines and human pancreatic cancer tissue microarrays. Treatment with naked anti-CD26 mAb KU44.13A did not have any effect on the growth and migration of cancer cells nor did it induce receptor downregulation. In contrast, treatment with anti-integrin α3 mAb KU44.22B inhibited growth in vitro of Capan-2 cells, increased migration of BxPC-3 and CFPAC-1 cells and induced antibody internalisation. Both novel mAbs are capable of detecting their target antigens by immunohistochemistry but not by Western blot. These antibodies are excellent tools for studying the role of integrin α3 and CD26 in the complex biology of pancreatic cancer, their prognostic and predictive values and the therapeutic potential of their humanised and/or conjugated versions in patients whose tumours overexpress integrin α3 or CD26.

Phase I Trial of an ICAM-1-Targeted Immunotherapeutic-Coxsackievirus A21 (CVA21) as an Oncolytic Agent Against Non Muscle-Invasive Bladder Cancer

PURPOSE

The CANON [CAVATAK in NON-muscle-invasive bladder cancer (NMIBC)] study evaluated a novel ICAM-1-targeted immunotherapeutic-coxsackievirus A21 as a novel oncolytic agent against bladder cancer.

PATIENTS AND METHODS

Fifteen patients enrolled in this "window of opportunity" phase I study, exposing primary bladder cancers to CAVATAK prior to surgery. The first 9 patients received intravesical administration of monotherapy CAVATAK; in the second stage, 6 patients received CAVATAK with a subtherapeutic dose of mitomycin C, known to enhance expression of ICAM-1 on bladder cancer cells. The primary endpoint was to determine patient safety and maximum tolerated dose (MTD). Secondary endpoints were evidence of viral replication, induction of inflammatory cytokines, antitumor activity, and viral-induced changes in resected tissue.

RESULTS

Clinical activity of CAVATAK was demonstrated by induction of tumor inflammation and hemorrhage following either single or multiple administrations of CAVATAK in multiple patients, and a complete resolution of tumor in 1 patient. Whether used alone or in combination with mitomycin C, CAVATAK caused marked inflammatory changes within NMIBC tissue biopsies by upregulating IFN-inducible genes, including both immune checkpoint inhibitory genes (PD-L1 and LAG3) and Th1-associated chemokines, as well as the induction of the innate activator RIG-I, compared with bladder cancer tissue from untreated patients. No significant toxicities were reported in any patient, from either virus or combination therapy.

CONCLUSIONS

The acceptable safety profile of CAVATAK, proof of viral targeting, replication, and tumor cell death together with the virus-mediated increases in "immunological heat" within the tumor microenvironment all indicate that CAVATAK may be potentially considered as a novel therapeutic for NMIBC.

Abstract 5215: Targeting of HOX-PBX binding in glioblastoma multiforme as a novel therapeutic treatment

The HOX genes encode a family of transcription factors that play an essential role in embryonic patterning. They are also aberrantly expressed in numerous cancers, including glioblastoma (GBM). Three Amino Acid Loop Extension Homeobox (TALE) proteins act as important co-factors for HOX proteins, modulating their binding affinities to genomic targets. TALE proteins include the Pre-B-cell leukemia homeobox (PBX) proteins 1-4, which bind anterior HOX proteins, facilitating their nuclear entry and limiting their degradation. HTL00-1 is a 2nd generation hexapeptide drug that inhibits HOX-PBX dimer formation, and has been shown to induce rapid apoptosis in cancer cells, but not normal cells, through the rapid upregulation of genes including cFos, DUSP1, and EGR1. We have found that both HOX and TALE genes are markedly dysregulated in primary GBM tumors as well as in murine (GL261), adult (LN18, U87-MG, U251-MG) and pediatric (KNS42, SF188) GBM cell lines, all of which are sensitive to HTL-001. These genes were even more highly expressed in experimentally induced GBM cancer stem cells (CSCs) compared with parental lines, with a corresponding increase in sensitivity to HTL-001. We also investigated the in vivo activity of HTL-001 in Black 6 mice carrying GL-261 subcutaneous and orthotropic tumors with twice weekly intraperitoneal delivery. HTL-001 was shown to cross the blood brain barrier using Alexa660 labelled peptide, and significant anti-tumor activity was observed in both subcutaneous and orthotropic models with increased survival (p&lt;0.02 and p&lt;0.0078, respectively). Resected tumors from HTL-001 treated mice showed marked evidence of apoptosis, tumor vasculature disruption and focal necrosis compared to untreated tumors. Taken together, our findings indicate that HOX-PBX inhibition is a potential therapeutic target for adult and pediatric GBM patients.

Citation Format: Richard Morgan, Monika Primon, Steven Shnyder, Susan Short, Balveen Kaur, Bangxing Hong, Izhar Bagwan, William Rogers, Hardev S. Pandha. Targeting of HOX-PBX binding in glioblastoma multiforme as a novel therapeutic treatment [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 5215.

Co-expression and prognostic significance of putative CSC markers CD44, CD133, wild-type EGFR and EGFRvIII in metastatic colorectal cancer

The presence of colorectal cancer stem cells (CSCs) have been associated with tumour initiation and resistance to therapy. This study investigated the co-expression and prognostic significance of the CSCs biomarkers CD44 and CD133 with wild-type EGFR (wtEGFR) and EGFRvIII in colorectal cancer (CRC). The expression of these biomarkers were determined in tumours from 70 patients with metastatic CRC by immunohistochemistry, and in a panel of human CRC cell lines, and their variants with acquired-resistance to EGFR inhibitors, by flow cytometry. The expression of CD44, CD133, wtEGFR and EGFRvIII were present in 17%, 23%, 26% and 13% of cases and the co-expression of CD44/CD133 with wtEGFR and EGFRvIII were present in 9% and 3% of the cases respectively. Only co-expression of CSCs/EGFRvIII (P = 0.037), and amphiregulin (P = 0.017) were associated with worse overall survival. Interestingly, disease-free survival was improved in BTC expressing patients (P = 0.025). In vitro CD133 expression and its co-expression with CD44 were associated with primary-resistance to irinotecan and acquired-resistance to anti-EGFR inhibitors respectively. Our results suggest co-expression of CSCs and EGFRvIII could be potential biomarkers of worse overall survival and resistance to therapy in patients with mCRC and warrants further validation in a larger cohort.

Metastatic endometrial cancer of the paranasal sinuses

Endometrial carcinoma is the fourth most common cancer affecting women in the UK. Its most frequent sites of spread are to the pelvic and para-aortic lymph nodes, vagina and peritoneum. We report a case of a 63-year-old woman with known endometrial cancer who presented with left facial swelling and eye displacement. Investigations revealed an expansile soft-tissue density mass arising within the bone, centred on the left zygoma, with exophytic extension into the left maxillary antrum, infratemporal fossa and inferiorly into the orbit. Endoscopic biopsies were taken and histology confirmed metastatic deposits of endometrial cancer. Clinicians should be aware that distant spread of endometrial cancer is linked with advanced disseminated disease and palliative treatments should be considered.

Abstract 5758: Generation and characterization of novel monoclonal antibodies against overexpressed CD109 on pancreatic cancer cells for use in diagnosis and therapy

Pancreatic cancer is one of the most aggressive and lethal types of cancer, and more effective therapeutic agents are urgently needed. Overexpressed cell surface antigens are ideal targets for therapy with monoclonal antibody (mAb)-based drugs, and several have been approved for the treatment of human cancers; however, none have approval for pancreatic cancer. Our aim was to discover novel overexpressed cell surface antigens in human pancreatic cancer cells using mAb technology. We have generated two novel mouse mAbs, KU42.33C and KU43.13A, against the human pancreatic cancer cell line BxPC-3. Using ELISA, flow cytometry, competitive assay and mass spectrometry, we discover that these two mAbs target two distinct epitopes on the external domain of CD109 that are overexpressed by varying amounts in human pancreatic cancer cell lines. Treatment with these two naked antibodies alone did not affect tumor cell growth in vitro or cell migration. Of the two mAbs, only KU42.33C was useful in determining the expression of CD109 in tumor cells by Western blot and immunohistochemistry. Immunohistochemistry of human pancreatic carcinoma arrays with mAb KU42.33C showed that 94% of the 65 human pancreatic adenocarcinoma cases were CD109 positive, with no expression in normal pancreatic tissues. Our results suggest that these two novel mAbs are excellent tools for determining the expression level of CD109 in the tumor specimens and sera of patients with a wide range of cancers, in particular pancreatic cancer, and for investigating its diagnostic, prognostic and predictive value. Further research should unravel the therapeutic potential of the humanized forms or the conjugated versions of such antibodies in patients whose tumors overexpress CD109 antigen.

Citation Format: Gustavo A. Arias-Pinilla, Angus Dalgleish, Satvinder Mudan, Izhar Bagwan, Tony Walker, Helmout Modjtahedi. Generation and characterization of novel monoclonal antibodies against overexpressed CD109 on pancreatic cancer cells for use in diagnosis and therapy [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 5758.

Development of novel monoclonal antibodies against CD109 overexpressed in human pancreatic cancer

Pancreatic cancer is one of the most aggressive and lethal types of cancer, and more effective therapeutic agents are urgently needed. Overexpressed cell surface antigens are ideal targets for therapy with monoclonal antibody (mAb)-based drugs, but none have been approved for the treatment of pancreatic cancer. Here, we report development of two novel mouse mAbs, KU42.33C and KU43.13A, against the human pancreatic cancer cell line BxPC-3. Using ELISA, flow cytometry, competitive assay and immunoprecipitation followed by mass spectrometry, we discovered that these two mAbs target two distinct epitopes on the external domain of CD109 that are overexpressed by varying amounts in human pancreatic cancer cell lines. Treatment with these two naked antibodies alone did not affect tumour cell growth or migration in vitro. Of the two mAbs, only KU42.33C was useful in determining the expression of CD109 in tumour cells by Western blot and immunohistochemistry. Interestingly, immunohistochemistry of human pancreatic carcinoma tissue arrays with mAb KU42.33C showed that 94% of the 65 human pancreatic adenocarcinoma cases were CD109 positive, with no expression in normal pancreatic tissues. Our results suggest that these two novel mAbs are excellent tools for determining the expression level of CD109 in the tumour specimens and sera of patients with a wide range of cancers, in particular pancreatic cancer, and for investigating its diagnostic, prognostic and predictive value. Further research is warranted and should aim to unravel the therapeutic potential of the humanised forms or conjugated versions of such antibodies in patients whose tumours overexpress CD109 antigen.

The impact of co-expression of wild-type EGFR and its ligands determined by immunohistochemistry for response to treatment with cetuximab in patients with metastatic colorectal cancer

Anti-EGFR mAbs cetuximab and panitumumab are routinely used for the treatment of patients with KRAS-wild type metastatic colorectal cancer (mCRC). However, in some patients their efficacy remains modest and with no clear association between the EGFR protein expression determined by PharmDx™ kit, and response to anti-EGFR therapies. Therefore, we investigated the relative expression and predictive value of wild-type EGFR (wtEGFR), mutated EGFRvIII and EGFR ligand proteins in mCRC patients treated with cetuximab. The expression levels of wtEGFR, EGFRvIII, and EGFR ligand were determined by immunohistochemistry (IHC) in 60 tumour specimens using specific antibodies. Sections were scored according to the percentage of positive tumour cells, intensity and cellular location of staining, and these were associated with response, overall survival (OS) and progression-free survival (PFS). At cut-off value > 5%, wtEGFR, and EGFRvIII were present in 44%, and 41%, betacellulin (BTC) in 72%, followed by epigen (67%), TGFα (58%), amphiregulin (34%), EGF (31%) of the cases, respectively and 96% of the wtEGFR positive cases had co-expression of at least one ligand. We found a significant association between the expression of wtEGFR and poor response to cetuximab. In addition, the co-expression of wtEGFR with one ligand at a cut-off value of > 5% and > 10% was associated with worse response to cetuximab (P = 0.021, and P = 0.005 respectively). We found a 3-fold and 5-fold increased risk of shorter OS with expression of BTC and epigen. Interestingly, the expression of wtEGFR and its co-expression with one or two ligands was associated with shorter PFS but not with OS. The relative expression of wtEGFR and its competing ligands, which is the target for therapeutic interventions with anti-EGFR antibodies, could serve as a more reliable predictive biomarker of response to therapy with anti-EGFR mAbs in mCRC patients and warrants further investigation in large prospective studies.

Abstract 5731: The prognostic significance of EGFR, HER-2, HER-4, EGFRvIII, c-MET, Ki67 and CD44 in patients with FIGO stages III and IV ovarian cancer

Overexpression and activation of HER (human epidermal growth factor receptor) family members have been reported in a wide range of epithelial tumours. Although several monoclonal antibodies (mAbs) and small molecule tyrosine kinase inhibitors (TKIs) specific for the HER members have been approved for the treatment of patients with a wide range of tumours, none has yet been approved for the treatment of patients with ovarian cancer. In some studies, the co-expression of other growth factor receptors (e.g. c-MET), the presence of cancer stem cells (CSCs) have been associated with resistance to therapy with the HER inhibitors. The aim of the present study was to determine the expression level and prognostic significance of the EGFR, HER-2, HER-4 and EGFRvIII, as well as c-MET, CD44 and cell proliferation marker Ki67 in 60 patients with FIGO stage III and IV ovarian cancer. The expression levels of these markers were determined, at different cut off values, using immunohistochemistry (IHC), and their associations with the overall survival and disease free survival were evaluated using Chi-squared and Kaplan-Meier survival curves and log-rank test as well as the univariate Cox-regression analysis. At cut off values of &gt;5% of tumour cells with positive immunostaining, 62%, 93%, 45%, 3%, 21%, 48%, and 95%, of the cases were positive for EGFR, HER-2, HER-4, EGFRvIII, c-MET, CD44, Ki67 respectively and 28% were positive for the co-expression of EGFR/HER-2/HER-4. The cellular location of immunostaining was membranous for EGFR, HER-2, c-MET and CD44 and was present in 33%, 10%, 3% and 50% of the cases examined respectively. In univariate analysis, the expression of EGFR at cut-off values of &gt;50% (HR, 3.57; 95% CI, 1.07 to 11.85; P= &lt;0.0001) and CD44 with 3+ intensity at cut-off values &gt;5 % (HR, 8.20; 95% CI, 2.02 to 33.2; P= &lt;0.0001) were associated with poorer overall survival. In contrast, the positive immunostaining of Ki67 at cut-off value &gt;5% of tumour cells, was associated with better overall survival (HR, 0.13; 95% CI, 0.02 to 0.73; P= 0.021 respectively). In addition, at cut-off value of &gt;5% of tumour cells with positive immunostaining, EGFR expression (HR, 2.83; 95% CI 1.18 to 6.77; P = 0.019) and &gt;10% (HR, 2.40; 95% CI 1.07 to 5.37; P= 0.032 ), as well as the co-expression of EGFR/HER-2 (HR, 2.83; 95% CI 1.18 to 6.77; P= 0.019), EGFR/c-MET (HR, 3.05; 95% CI 1.2 to 7.75; P= 0.019) and EGFR/Ki67 (HR, 2.83; 95% CI 1.18 to 6.77; P= 0.019) were all associated with poorer disease free survival in these patients. Our results suggest that co-expression of EGFR\HER-2\HER4 is common in patients with Stages III and IV ovarian cancers and support the need for investigations on the therapeutic potential of various forms of pan-HER inhibitors in such patients.

Citation Format: Soozana Puvanenthiran, Sharadah Essapen, Ben Haagsma, Izhar Bagwan, Alan Seddon, Helmout Modjtahedi. The prognostic significance of EGFR, HER-2, HER-4, EGFRvIII, c-MET, Ki67 and CD44 in patients with FIGO stages III and IV ovarian cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 5731. doi:10.1158/1538-7445.AM2017-5731

Expression profiling and significance of VEGF-A, VEGFR2, VEGFR3 and related proteins in endometrial carcinoma

BACKGROUND

Angiogenesis plays a key role in the progression of various tumors, including endometrial carcinomas. Several cytokines and their associated receptors are shown to be involved, particularly VEGF-A with VEGFR1, -2 and -3.

METHODS

The expressions of VEGF-A, VEGFR2 and VEGFR3 were studied in by immunohistochemistry in 76 endometrial carcinoma specimens. VEGFR2 and VEGFR3 receptor expression were also studied by qRT-PCR in 17 tumors in comparison to normal endometrium. The expression profiles were correlated with tumor type, grade, stage, lymphovascular invasion, disease free survival, and the expressions of other cytokine receptors (EGFR, CXCR1 and CXCR2).

RESULTS

Immunohistochemically, 63% of endometrial cancers expressed VEGF-A, 55% VEGFR2 and 26% VEGFR3. VEGFR3 was significantly correlated with tumor stage (p=0.02), with a trend towards poorer disease free survival (p=0.09). VEGF-A was significantly correlated with microvessel density (p<0.01). Using qRT-PCR, increased expression of VEGFR2 (17.2-fold) and VEGFR3 (21.9-fold) was seen in endometrial carcinomas compared with normal endometrium, with significant correlations among the expression levels of VEGFR2, VEGFR3, EGFR, CXCR1 and CXCR2.

CONCLUSION

Our study suggests that evaluation of VEGFR3 expression in tumors may provide prognostic data, and help identify patients who would best benefit from anti-angiogenic therapeutic agents. This is the first report showing correlations between the expressions levels of the different receptors.

Co-expression of HER family members in patients with Dukes' C and D colon cancer and their impacts on patient prognosis and survival

The human epidermal growth factor receptor (EGFR) is an important therapeutic target in patients with metastatic colorectal cancer and anti-EGFR antibodies cetuximab and panitumumab have been approved for the treatment of such patients. Despite these advances, the duration of response in some patients can be limited. Since, EGFR is capable of forming heterodimers with the other members of the HER (Human epidermal receptor) family, it is important to investigate the co-expression and prognostic significance of all members of the HER family in colorectal cancer patients. The expression of the HER family members were determined in tumour specimens from 86 patients with Dukes’ C and D (metastatic) colon cancer using immunohistochemistry. Sections were scored by the percentage of positive tumour cells and intensity of staining. Their associations with clinicopathological parameters, and overall survival and disease free survival were evaluated using univariate and multivariate analysis. Overall, 43%, 77%, 52% and 92% of the cases were EGFR, HER-2, HER-3 and HER-4 positive respectively. Interestingly, 35%, 24%, 43%, and 18% of the cases had co-expression of EGFR/HER-2, EGFR/HER-3, EGFR/HER-4 and all four members of the HER family respectively. Of these, only the expression of EGFR and co-expression of EGFR/HER-4 were associated with poorer disease-free survival in both univariate and multivariate analysis. Co-expression of all members of the HER family in colon cancer supports the need for further investigations on their predictive value for response to therapy with anti-EGFR mAbs and whether such sub-population of patients may benefit from therapy with the new generation of pan-HER inhibitors.

Abstract 2723: The chorio-allantoicmembrane (CAM) model for testing HOX gene antagonism in pancreatic cancer

Background

Pancreatic ductal adenocarcinoma (PDAC) is one of the most aggressive solid cancers with a 5-year survival rate approaching a dismal 5%. New therapeutic targets need to be identified in order to increase survival rates.

HOX genes are a family of 39 transcription factors involved in embryonic development and which have been found to be dys-regulated in PDAC. HOX gene function can be antagonised by HXR9, a peptide that competitively inhibits binding of HOX proteins to their co-factor PBX. We established that the CAM model recapitulates human PDAC, including desmoplasia, and is highly suitable for the evaluation of HXR9 in vivo.

Experimental procedure

Four PDAC-derived cell lines (AsPc-1, BxPc-3, PaCa-3 and PancTu1) were treated in vitro with HXR9. Ic50s were determined using both MTS and LDH assays. FACS analysis was used to determine mechanisms of cell death. Cell lines were subsequently implanted in the CAM using Marigel™ on embryonic day (EDD) 10. Tumour growth curves were established and tumours were resected and subsequently stained with

PDAC-specific cell surface markers. CAM-tumours were treated with intra-tumoral injection of HXR9 on EDD 16.

Results

PDAC-derived cell lines were sensitive to HXR9 in vitro with IC50s ranging from 13-45μM. Annexin V-PE analysis showed apoptosis was induced in HXR9 treated cells. PDAC was established in the CAM from cell lines and showed remarkable similarity to human disease including desmoplasia and phonotypic markers. Intra-tumoral treatment of CAM-PDAC showed evidence of tumour regression and apoptosis.

Conclusions

The CAM model is a simple and robust assay for modelling human PDAC and recapitulates architecture including desmoplasia. The CAM assay is suitable for testing the efficacy of HXR9. Targeting HOX gene dys-regulation is a novel approach for the treatment of PDAC.

Citation Format: Sophie Gray, Stephen Metcalf, Angela Boxall, Gary Middleton, Izhar Bagwan, Hardev Pandha, Richard Morgan. The chorio-allantoicmembrane (CAM) model for testing HOX gene antagonism in pancreatic cancer. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 2723. doi:10.1158/1538-7445.AM2013-2723

CDKN2A, NF2, and JUN are dysregulated among other genes by miRNAs in malignant mesothelioma -A miRNA microarray analysis

Malignant mesothelioma (MM) is an aggressive cancer arising from mesothelial cells, mainly due to former asbestos exposure. Little is known about the microRNA (miRNA) expression of MM. miRNAs are small noncoding RNAs, which play an essential role in the regulation of gene expression. This study was carried out to analyze the miRNA expression profile of 17 MM samples using miRNA microarray. The analysis distinguished the overall miRNA expression profiles of tumor tissue and normal mesothelium. Differentially expressed miRNAs were found in tumor samples compared with normal sample. Twelve of them, let-7b*, miR-1228*, miR-195*, miR-30b*, miR-32*, miR-345, miR-483-3p, miR-584, miR-595, miR-615-3p, and miR-885-3p, were highly expressed whereas the remaining nine, let-7e*, miR-144*, miR-203, miR-340*, miR-34a*, miR-423, miR-582, miR-7-1*, and miR-9, were unexpressed or had severely reduced expression levels. Target genes for these miRNAs include the most frequently affected genes in MM such as CDKN2A, NF2, JUN, HGF, and PDGFA. Many of the miRNAs were located in chromosomal areas known to be deleted or gained in MM such as 8q24, 1p36, and 14q32. Furthermore, we could identify specific miRNAs for each histopathological subtype of MM. Regarding risk factors such as smoking status and asbestos exposure, significantly differentially expressed miRNAs were identified in smokers versus nonsmokers (miR-379, miR-301a, miR-299-3p, miR-455-3p, and miR-127-3p), but not in asbestos-exposed patients versus nonexposed ones. This could be related to the method of assessment of asbestos exposure as asbestos remains to be the main contributor to the development of MM.