Squamous Tumor Research Articles

Immunohistochemical expression of keratins 8 and 19 in odontogenic cysts and tumors

Objective: Cytokeratins (CKs) are integral components in the formation of enamel, dentin and/or cemental matrix and their subsequent mineralization. K8 and K19 are known to be chemically homologous during the formation of tooth structures. This feature is rather unique and is expressed across the milieu of odontogenic tissues in the physiological and pathological states. The present study was designed to evaluate the expressions of K8 and K19 in odontogenic lesions immunohistochemically and to test the hypothesis that they can be used to identify the odontogenic epithelium. Study Design: K8 and K19 were assessed in 60 cases of odontogenic lesions retrieved from the archival files, which included ameloblastoma (18), ameloblastic carcinoma (2), adenomatoid odontogenic tumor (AOT) (9), squamous odontogenic tumor (SOT) (1), odontogenic keratocyst (OKC) (10), dentigerous cyst (10), and radicular cyst (10), including two cases of normal gingiva and follicular tissue. Results: K8 was expressed in 53/60 (88.3%) and K19 in 56/60 (93.3%) odontogenic lesions. The labeling for K19 was found to be more intense compared to that for K8. Further, K8 and K19 were found to be positive in all the gingival and follicular tissues. Conclusions: Positive expressions of K8 and K19 in all the odontogenic lesions studied suggest that these can be used as definitive markers for identifying the odontogenic epithelium. However, the intense and consistent expression of K19 suggests that this CK is extremely sensitive in identifying the odontogenic epithelium.

DAP1 high expression increases risk of lymph node metastases in squamous cell carcinoma of the oral cavity.

Death-associated protein 1 (DAP1) is a member of the DAP family. Its expression is associated with cell growth and normal death of the neoplastic cells, regulated by the mammalian target of the rapamycin protein. Activated DAP1 negatively regulates autophagy, which has been associated with the development and progression of several diseases, such as cancer, and with prognosis and survival of diverse tumor types. Therefore, in this study we analyzed DAP1 expression in 54 oral squamous cell carcinoma tumor samples and in 20 non-tumoral margins by immunohistochemistry. The results showed that DAP1 is more frequently expressed in tumor tissues compared with marginal non-tumoral cells. Additionally, high DAP1 expression is associated with a 4-fold increase in the risk of lymph node metastases. Our results suggest that the DAP1 protein can be used as a potential marker of lymph node metastases predisposition, helping define the best therapy for each patient to minimize risk of developing metastases.

Miles to Discover in Histological Grading of Odontogenic Tumours.

Odontogenic tumours (OTs) are lesions of great interest and importance to oral pathologists and maxillofacial surgeons alike, who for several decades have studied, catalogued these lesions and developed modalities for adequate treatment [1]. Ameloblastoma is the most common and most intriguing of all odontogenic tumours. Although benign it is highly polymorphic, due to its ability to undergo various forms of metaplasia. This has given rise to variants of ameloblastoma in which the stimulus for metaplastic change is poorly understood and has been attributed to the multipotentiality of odontogenic epithelium [2]. In the indexed case, 12-year-old boy presented with the complaint of gradually increasing painless growth in lower front teeth region since 8 months. No evident extraoral swelling or asymmetry was noticed. Regional lymph nodes were not clinically palpable and there was no history of trauma to the same site. Intraoral examination revealed approximately a 2.5x4cm, non tender mucosal sessile mass on lingual aspect of anterior mandible extending from central incisor to second premolar on left side obliterating the lower labial vestibule [Table/Fig-1]. [Table/Fig-1]: Intraoral picture reveals a sessile mass on lingual aspect of anterior mandible There was a faintly palpable anterior lingual expansion. The mandibular incisors, canine and premolar of left side were found to be non vital on thermal testing. Orthopantomograph (OPG) revealed a well circumscribed unilocular radiolucency in the anterior mandible extending from 44 to 35 without cortication. Thinning of lower border of mandible was seen. Root resorption of associated teeth due to pressure was evident [Table/Fig-2]. Considering the benign nature of the lesion, its site of occurrence i.e. anterior to first molars and unilocular appearance, central giant cell granuloma was considered as provisional diagnosis and excisional biopsy was done. [Table/Fig-2]: OPG showing a well circumscribed unilocular radiolucency in the anterior mandible with thinning of lower border Histopathological sections of this case showed well encapsulated tumour mass with extensive areas of squamous differentiation and features of plexiform ameloblastoma [Table/Fig-3]. [Table/Fig-3]: Photomicrograph reveals a well encapsulated tumour mass with extensive areas of squamous differentiation mixed with plexiform pattern (H&E, 10X) Few areas showed material secretion in the tumour matrix which were suggestive of calcifying epithelial odontogenic tumour but when stained with Congo red, came out to be negative [3]. Calcifications or even multinucleated giant cells were not evident in the submitted tissue. Keratin pearl formation was not seen but individual cell keratinization and squamous differentiation were evident throughout the stroma. The tumour appeared to be in biphasic pattern where at one end the tumour cells appeared to be stretched out making the intercellular ridges prominent whereas at the other end, tumour showed squamous differentiation, loss of intercellular bridges and cohesive tumour cells arranged in thick sheets [Table/Fig-4]. Tumour cells were positive for cytokeratin whereas surrounding material was negative [Table/Fig-5]. [Table/Fig-4]: Photomicrograph reveals area of cohesive tumour cells with squamous differentiation & loss of intercellular bridges (H&E, 10X) [Table/Fig-5]: Photomicrograph shows cytokeratin positivity in tumour cells (H&E, 10X) After extensive search in literature only three odontogenic tumours which show keratinization or squamous metaplasia were found. Acanthomatous ameloblstoma exhibit squamous metaplasia of stellate reticulum with or without keratin pearl formation [4]. However, in the present case frank keratin or squamous metaplasia was not seen but only squamous differentiation and individual cell keratinization were seen. Squamous odontogenic tumour also shows squamous metaplasia [5] but in the present case tumour was not arranged in follicles as well as material secretion by tumour cells did not appear to be keratin and tumour cells were not flattened squamous or cuboidal arranged in follicles. Keratoameloblastoma is a heterogenous group of odontogenic neoplasms which exhibit keratin formation in the connective tissue stroma [6]. Such frank keratin formation was absent in the present case. The index case is not of intraosseous squamous cell carcinoma as there was no dysplasia and few areas showed frank stellate reticulum like cells. Moreover, the present case is well encapsulated tumour supporting benign nature which is in contradiction to malignancy i.e. squamous cell carcinoma.

CFD modeling and image analysis of exhaled aerosols due to a growing bronchial tumor: towards non-invasive diagnosis and treatment of respiratory obstructive diseases.

Diagnosis and prognosis of tumorigenesis are generally performed with CT, PET, or biopsy. Such methods are accurate, but have the limitations of high cost and posing additional health risks to patients. In this study, we introduce an alternative computer aided diagnostic tool that can locate malignant sites caused by tumorigenesis in a non-invasive and low-cost way. Our hypothesis is that exhaled aerosol distribution is unique to lung structure and is sensitive to airway structure variations. With appropriate approaches, it is possible to locate the disease site, determine the disease severity, and subsequently formulate a targeted drug delivery plan to treat the disease. This study numerically evaluated the feasibility of the proposed breath test in an image-based lung model with varying pathological stages of a bronchial squamous tumor. Large eddy simulations and a Lagrangian tracking approach were used to model respiratory airflows and aerosol dynamics. Respirations of tracer aerosols of 1 µm at a flow rate of 20 L/min were simulated, with the distributions of exhaled aerosols recorded on a filter at the mouth exit. Aerosol patterns were quantified with multiple analytical techniques such as concentration disparity, spatial scanning and fractal analysis. We demonstrated that a growing bronchial tumor induced notable variations in both the airflow and exhaled aerosol distribution. These variations became more apparent with increasing tumor severity. The exhaled aerosols exhibited distinctive pattern parameters such as spatial probability, fractal dimension, and multifractal spectrum. Results of this study show that morphometric measures of the exhaled aerosol pattern can be used to detect and monitor the pathological states of respiratory diseases in the upper airway. The proposed breath test also has the potential to locate the site of the disease, which is critical in developing a personalized, site-specific drug delivery protocol.

Effect of Fe3O4 Nanoparticles on Skin Tumor Cells and Dermal Fibroblasts.

Iron oxide (Fe3O4) nanoparticles have been used in many biomedical approaches. The toxicity of Fe3O4 nanoparticles on mammalian cells was published recently. Though, little is known about the viability of human cells after treatment with Fe3O4 nanoparticles. Herein, we examined the toxicity, production of reactive oxygen species, and invasive capacity after treatment of human dermal fibroblasts (HDF) and cells of the squamous tumor cell line (SCL-1) with Fe3O4 nanoparticles. These nanoparticles had an average size of 65 nm. Fe3O4 nanoparticles induced oxidative stress via generation of reactive oxygen species (ROS) and subsequent initiation of lipid peroxidation. Furthermore, the question was addressed of whether Fe3O4 nanoparticles affect myofibroblast formation, known to be involved in tumor invasion. Herein, Fe3O4 nanoparticles prevent the expression alpha-smooth muscle actin and therefore decrease the number of myofibroblastic cells. Moreover, our data show in vitro that concentrations of Fe3O4 nanoparticles, which are nontoxic for normal cells, partially reveal a ROS-triggered cytotoxic but also a pro-invasive effect on the fraction of squamous cancer cells surviving the treatment with Fe3O4 nanoparticles. The data herein show that the Fe3O4 nanoparticles appear not to be adequate for use in therapeutic approaches against cancer cells, in contrast to recently published data with cerium oxide nanoparticles.

CD137 enhancement of HPV positive head and neck squamous cell carcinoma tumor clearance.

Standard-of-care cisplatin and radiation therapy (CRT) provides significant tumor control of human papillomavirus (HPV)-mediated head and neck squamous cell carcinomas (HNSCCs); this effectiveness depends on CRT-mediated activation of the patient’s own immune system. However, despite good survival, patients suffer significant morbidity necessitating on-going studies to define novel therapies that alleviate this burden. Given the role of the immune system in tumor clearance, immune modulation may further potentiate the CRT-activated response while potentially decreasing morbidity. CD137, an inducible cell surface receptor found on activated T cells, is involved in differentiation and survival signaling in T cells upon binding of its natural partner (CD137L). A number of studies have shown the effectiveness of targeting this immune-stimulatory pathway in regards to tumor clearance. Here, we test its role in HPV+ HNSCC tumor clearance using a previously characterized mouse model. We show that amplification of this stimulatory pathway synergizes with CRT for enhanced tumor clearance. Interestingly, tumor clearance is further potentiated by local tumor cell expression of CD137L.

Abstract 983: Intratumor heterogeneity in non-small cell lung cancer inferred by multi-region exome sequencing

Abstract Lung cancer is the most common cancer worldwide, and a leading cause of cancer-related death. Despite improvements in molecular diagnosis and targeted therapies, the 5-years overall survival remains poor. To obtain a better insight into the genetic architecture of the most common type of lung cancer, non-small lung cancer (NSCLC), we performed multi-region DNA sequencing on 7 resected NSCLC samples. Ultra-deep sequencing of a comprehensive cancer gene panel and whole-exome sequencing revealed intratumor heterogeneity in all samples, with several putative tumor driver mutations present in some but not all regions of a tumor. Phylogenetic tree analyses based on non-synonymous mutations revealed a branched evolution pattern in all tumors. An adenosquamous tumor showed striking intratumor heterogeneity, with only a third of all non-synonymous mutations shared across all tumor regions, and clear separation of adenocarcinoma and squamous cell carcinoma tumor regions in the remaining two-third of the mutations. Our multi-region exome sequencing data also revealed regional differences in DNA copy number alterations. Some tumors, relatively homogeneous in terms of mutations, displayed high levels of intratumor heterogeneity in terms of DNA copy number changes, indicating the presence of distinct patterns of intratumor heterogeneity that might contribute to disease progression in different tumours. Overall, our multi-region deep exome sequencing data revealed intratumor heterogeneity in NSCLC, demonstrating branched evolution, both in terms of non-synoymous mutations and DNA copy number alterations, which has important implications for our understanding of the clonal evolution of NSCLC. Citation Format: Elza De Bruin, Nicholas McGranahan, Lucy Yates, Mariam Jamal-Hanjani, Max Salm, Richard Mitter, Seema Shafi, Nirupa Murugaesu, Andrew Rowan, Marco Gerlinger, David Wedge, Stuart Horswell, Ignacio Varela, Warren Tom, Chaitali Parikh, Timothy Harkins, Clarence Lee, Nik Matthews, Aengus Stewart, Peter Campbell, Charles Swanton. Intratumor heterogeneity in non-small cell lung cancer inferred by multi-region exome sequencing. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 983. doi:10.1158/1538-7445.AM2014-983

Abstract 4678: Application of the EGFR in squamous lung cancer and its relationship between p63

Abstract OBJECTIVE: Epidermal growth factor receptor (EGFR) mutations are rarely found in squamous cell carcinoma (SQC). METHODS: Between J February 2010 and March 2013, we investigated the incidence of EGFR activating mutations in SQC of the lung using the automated direct sequencing of polymerase chain reaction products method. The efficacies of formal therapy, observation, targeting therapy (EGFR-tyrosine kinase inhibitors [TKIs]) were retrospectively evaluated in patients with EGFR-mutated SQC. Further pathologic analyses were performed using immunohistochemistry. RESULTS: Sixteen of the 282 patients with SQC (5.67%) had EGFR mutations, including exon 19 deletion (7 of 16 patients, 44%), L858R point mutation in exon 21 (9 of 16, 56%). The patients' median progression-free survival (PFS) and median overall survival (OS) in formal therapy, observation and targeting therapy were 6.28 and 9.03, 5.23 and 6.17, and 4.20 and 10.57 months. The median OS of 4 EGFR-mutated patients received p63 (partly +) was 11.28 months (95% confidence interval [CI], 6.33-16.23months) verse that of 11 EGFR-mutated patients received p63 (+) was 3.57 months (95%CI, 1.75- 5.39 months) (p=0.039). CONCLUSION: EGFR-TKIs for EGFR-mutated SQC are generally inferior to that for EGFR-mutated ADC. Chemotherapy or radiation therapy seemed to be less inferior to TKI therapy considering the PFS and OS results and the economy when patients are in good status. Patients presenting partly + of p63 had longer OS than p63 + patients. EGFR and p63 might be two separate factors which affected the proliferation of squamous tumor cells and result remained to be confirmed by large samples. KEYWORDS: squamous lung cancer, SQC,epidermal growth factor receptor, EGFR, P63 Note: This abstract was not presented at the meeting. Citation Format: Yiping Han, Bibo Wang, Ling Huang, Li Qiang. Application of the EGFR in squamous lung cancer and its relationship between p63. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 4678. doi:10.1158/1538-7445.AM2014-4678

Abstract 4083: Opposing roles of B cells in Ras-driven squamous tumor development dependent on tissue compartment of oncogene expression and tumor phenotype

Abstract Studies in mouse models and human cancers show that B cells can both promote and inhibit cancer development, but the mechanisms generating these alternate outcomes are not well understood. Here we have developed a mouse model of Ras-driven epidermal tumor development in which opposite effects of B cells are manifest, dependent on the differentiation state of cells expressing oncogenic Ras. We used a doxycycline regulatable bitransgenic system to target oncogenic H-RasV12G to either the basal/stem cell (Keratin14-rTAxtetORasV12G, K14Ras) or differentiating (Involucrin-tTA x tetORasV12G, InvRas) compartment of the epidermis. K14Ras mice develop focal squamous cell carcinoma while InvRas mice develop squamous papillomas within 30 days on threshold levels of doxycycline resulting in ∼10 tumors/mouse. On a Rag1-/- background we observed opposite tumor responses, with InvRasRag1-/- mice developing fewer tumors and K14RasRag1-/- mice developing more tumors with shorter latency than Rag1+/+ controls. Depletion of CD4+ T cells caused an overall increase in tumor burden compared to isotype controls in both models, while adoptive transfer of naïve CD4+ T cells (purity ≥ 93%) increased tumor burden in K14RasRag1-/- mice, but suppressed tumors in InvRasRag1-/- mice. Tumors from CD4 transferred K14RasRag1-/- mice had a predominant Th1 infiltrate with few Tregs and increased tumor-infiltrating neutrophils compared to mock transferred controls. Conversely, CD4+ T cells adoptively transferred to InvRasRag1-/- mice displayed a regulatory phenotype with low IFNγ and high Foxp3, which was associated with a decrease in neutrophilic infiltration. In contrast, B cell depletion with anti-CD20 caused a significant suppression of tumor outgrowth in InvRas mice but enhanced tumor burden in K14Ras mice. Furthermore, adoptive transfer of magnetically purified splenic B cells into K14RasRag1-/- mice suppressed tumor formation, and co-transfer of B cells with CD4+ T cells reduced tumor development to a greater extent than B cells alone. Tumor-infiltrating B cells from co-transferred mice had greater percentage of B regulatory cells, and increased costimulatory molecule expression compared to B cells alone, resembling K14RasRag1+/+ controls. B cell co-transfer significantly increased Foxp3+ Treg percentage to levels similar to K14RasRag1+/+ mice as measured by flow cytometry. Taken together these results show that B cells are the critical lymphocyte driving both tumor suppression or promotion in this model, that the differentiation state of the tumor initiating cell determines the B cell response, and that interactions between CD4+ T cells and B cells may be important for the development of a proper anti-tumor immune response. Citation Format: Michael A. Podolsky, Andrew Gunderson, Kyle Breech, Adam B. Glick. Opposing roles of B cells in Ras-driven squamous tumor development dependent on tissue compartment of oncogene expression and tumor phenotype. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 4083. doi:10.1158/1538-7445.AM2014-4083

Incidence and clinical implication of tumor cavitation in patients with advanced non-small cell lung cancer induced by Endostar, an angiogenesis inhibitor.

Antiangiogenesis plays a key role in the treatment of non-small lung cancer (NSCLC). We observed the cavitation of lesions in patients with stage IIIB/IV NSCLC treated with Endostar and vinorelbine-cisplatin (NP) chemotherapy, and evaluated the imaging characteristics and clinical outcome of patients who developed tumor cavitation. Our study included 105 untreated NSCLC patients who received Endostar in combination with NP chemotherapy at the Tianjin Lung Cancer Center. Chest computed tomography (CT) was performed to evaluate the efficacy every two cycles. The number of activated circulating endothelial cells (aCECs) was measured by flow cytometry. Rates of tumor cavitation were documented and their clinical CT imaging data were analyzed. Tumor cavitation occurred in 11 of the 105 (10.5%) patients treated with Endostar and NP. The response rates were 37.2% (35/94) in patients without cavitation, 27.3% (3/11) evaluated by Response Evaluation Criteria in Solid Tumors, and 100.0% (11/11) if evaluated by an alternate method in patients who developed cavitation. Three of the 11 cases with cavitation had a centrally located tumor. No patients had hemoptysis or any other severe side effects. Compared with patients not developing cavitation, cavity formation resulted in a longer median survival time (13.6 vs. 11.8 months, P = 0.011) and an increase in the number of aCECs (244.4/10(5) vs. 23.3/10(5), P = 0.000). Intratumoral cavitation induced by Endostar is common in NSCLC patients, and is not correlated with squamous histology, tumor location or pulmonary hemorrhage. Cavitation might have a significant effect on the number of aCECs and overall prognosis.

Bavituximab plus paclitaxel and carboplatin for the treatment of advanced non-small-cell lung cancer

ObjectiveBavituximab is a phosphatidylserine (PS)-targeting monoclonal antibody with immune-modulating and tumor-specific vascular targeting properties. Preclinical studies have shown activity against numerous solid tumors and at least an additive effect in combination with chemotherapy. This study evaluated bavituximab in combination with paclitaxel and carboplatin in patients with previously untreated, locally advanced or metastatic non-small-cell lung cancer (NSCLC). Patients and methodsThis phase II, open-label study (NCT00687817) was conducted in 49 patients with stage IIIB/IV NSCLC utilizing a Simon two-stage design. Patients were treated with up to six cycles of carboplatin area under the concentration–time curve (AUC) 5 plus paclitaxel 175mg/m2 every 21 days with weekly bavituximab 3mg/kg followed by bavituximab monotherapy until progression or unacceptable toxicity. ResultsThe primary efficacy endpoint of overall response rate (ORR) was 40.8% (complete response [CR] 2.0%, partial response [PR] was 38.8%). Median progression-free survival (PFS) and overall survival (OS) were 6.0 and 12.4 months, respectively. Treatment-related adverse events (AEs) occurred in 40.8% of patients. The most common treatment-related AEs were anemia (10.2%), asthenia, vomiting, paresthesia, anorexia, and fatigue (6.1% each). One patient with a central, cavitating squamous tumor developed fatal hemoptysis and aspiration. ConclusionBavituximab in combination with paclitaxel–carboplatin as first-line therapy demonstrated a tolerable safety profile and potential efficacy in this single-arm phase II trial in patients with advanced local or metastatic NSCLC. Randomized trials with this regimen are in progress. ClinicalTrials.gov identifierNCT00687817.

Relevance of insulin-like growth factor 1 receptor gene expression as a prognostic factor in non-small-cell lung cancer.

Signalling through the insulin-like growth factor 1 receptor (IGF-1R) is implicated in carcinogenesis, metastasis, and resistance to cytotoxic cancer therapies. The purpose of this study was to investigate the prognostic role of IGF-1R expression in surgically resected non-small-cell lung cancer (NSCLC), and responses to IGF-1R tyrosine kinase inhibitor NVP-ADW742 in a panel of lung cancer cell lines. Insulin-like growth factor 1 receptor (IGF-1R) expression was evaluated by quantitative RT-PCR in 115 NSCLC samples and in a panel of 6 NSCLC cell lines. Cytotoxicity experiments with IGF-1R inhibitor and conventional systemic drugs such as paclitaxel in cell lines were realised. Insulin-like growth factor 1 receptor (IGF-1R) was differentially expressed across histologic subtypes, with the lowest levels observed in squamous cell tumours. Median survival was longer in patients with squamous tumour histology expressing low IGF-1R levels. In multivariable analysis, ageing and high tumour stage were significant predictors of worse overall survival. The hazard of death was lower in patients with squamous histology and low IGF-1R gene expression. There was no correlation between IGF-1R expression and response to tyrosine kinase inhibitor in cell lines tested. However, combination drug treatment resulted in synergistically enhanced antiproliferative effects on several cell lines. These findings suggest that IGF-1R is a potential target for therapy in NSCLC patients. Combination therapies will have an important role in treatment.

TGFβ loss activates ADAMTS-1-mediated EGF-dependent invasion in a model of esophageal cell invasion

The TGFβ signaling pathway is essential to epithelial homeostasis and is often inhibited during progression of esophageal squamous cell carcinoma. Recently, an important role for TGFβ signaling has been described in the crosstalk between epithelial and stromal cells regulating squamous tumor cell invasion in mouse models of head-and-neck squamous cell carcinoma (HNSCC). Loss of TGFβ signaling, in either compartment, leads to HNSCC however, the mechanisms involved are not well understood. Using organotypic reconstruct cultures (OTC) to model the interaction between epithelial and stromal cells that occur in dysplastic lesions, we show that loss of TGFβ signaling promotes an invasive phenotype in both fibroblast and epithelial compartments. Employing immortalized esophageal keratinocytes established to reproduce common mutations of esophageal squamous cell carcinoma, we show that treatment of OTC with inhibitors of TGFβ signaling (A83-01 or SB431542) enhances invasion of epithelial cells into a fibroblast-embedded Matrigel/collagen I matrix. Invasion induced by A83-01 is independent of proliferation but relies on protease activity and expression of ADAMTS-1 and can be altered by matrix density. This invasion was associated with increased expression of pro-inflammatory cytokines, IL1 and EGFR ligands HB-EGF and TGFα. Altering EGF signaling prevented or induced epithelial cell invasion in this model. Loss of expression of the TGFβ target gene ROBO1 suggested that chemorepulsion may regulate keratinocyte invasion. Taken together, our data show increased invasion through inhibition of TGFβ signaling altered epithelial-fibroblasts interactions, repressing markers of activated fibroblasts, and altering integrin-fibronectin interactions. These results suggest that inhibition of TGFβ signaling modulates an array of pathways that combined promote multiple aspects of tumor invasion.

Squamous odontogenic tumor of the maxilla: a case report and review of the literature

Squamous odontogenic tumors are rare neoplasms of the jaw that are benign and locally infiltrative. The tumor originates in the gingival rests of Malassez, remnants of dental lamina or gingival surface epithelium. This type of tumor was first described by Pullon et al. (Oral Surg Oral Med Oral Pathol 40:616–630, 1975). The clinical presentation is mostly asymptomatic, though pain and tooth mobility may also occur. Radiographically, the tumor presents as a triangular radiolucent lesion found mostly in the maxilla and present between the roots of the teeth. Histologically, it may appear similar to acanthomatous and desmoplastic ameloblastoma; hence, it can present problems in differential diagnosis. Here, we describe a case of squamous odontogenic tumor of the anterior maxilla in a middle-aged Indian man.

Keratoacanthoma Pathobiology in Mouse Models

Recently we described skin tumors driven by skin-specific expression of Zmiz1 and here we define keratoacanthoma pathobiology in this mouse model. Similar to human keratoacanthoma development, we were able to segregate murine keratoacanthomas into three developmental phases: growth, maturation, and regression. These tumors had areas with cellular atypia, high mitotic rate, and minor local invasion in the growth phase, but with development they transitioned to maturation and regression phases with evidence of resolution. The early aggressive appearance could easily be misdiagnosed as a malignant change if the natural pathobiology was not well-defined in the model. To corroborate these findings in the Zmiz1 model, we examined squamous skin tumors from another tumor study in aging mice, and these tumors followed a similar biological progression. Lastly, we were able to evaluate the utility of the model to assess immune cell infiltration (F4/80, B220 Granzyme B, CD3 cells, arginase-1) in the regression phase; however, because inflammation was present at all phases of development, a more comprehensive approach will be needed in future investigations. Our study of keratoacanthomas in selected murine models suggests that these squamous tumors can appear histologically aggressive during early development, but with time will enter a regression phase indicating a benign biology. Importantly, studies of squamous skin tumor models should be cautious in tumor diagnosis as the early growth distinction between malignant versus benign based solely on histopathology may not be easily discerned without longitudinal studies to confirm the tumor pathobiology.

Effect of FGFR1 on epithelial-mesenchymal transition and EGFR resistance in HNC: A systems biology approach.

6091 Background: Fibroblast Growth Factor Receptor 1 (FGFR1) plays an important role in cancer and is an emerging treatment target for squamous lung cancer and other tumor types. We determined the ...

English

Primary squamous carcinoma is a rare type of metaplastic carcinoma of the breast, incidence being less than 0.1% of all breast carcinomas. The non-keratinizing variant can mimic several rare types of breast carcinomas, prognosis and therapeutic modalities of which are dissimilar. Histopathological examination is gold standard in diagnosing these tumors. Accurate diagnosis employing special stains and immunohistochemistry is mandatory as they are triple negative unlike infiltrating ductal carcinoma NOS, and have aggressive course, poor prognosis and distinctive treatment modalities. Other unique features include less frequent axillary nodal metastasis and necessity to rule out metastatic squamous carcinomas to the breast from other primary sites in these patients. We present a 60 years old lady with a hard lump in the left breast, with no significant past history. Physical examination was suggestive of carcinoma of breast with axillary lymphadenopathy. Histopathological examination revealed squamous carcinoma of breast positive for p63 and cytokeratin (CK) 5/6. Her chest X-ray, abdominal ultrasonography, oral cavity, laryngobronchoscopy, cystoscopy and cervical Pap smears were unremarkable ruling out the possibility of primary squamous tumor in other common organs.

1α,25-dihydroxyvitamin D3 modulates CYP2R1 gene expression in human oral squamous cell carcinoma tumor cells.

Oral squamous cell carcinomas (OSCC) are the most common malignant neoplasms associated with mucosal surfaces of the oral cavity and oropharynx. 1α,25-Dihydroxyvitamin D3 (1,25(OH)2D3) is implicated as an anticancer agent. Cytochrome P450 2R1 (CYP2R1) is a microsomal vitamin D 25-hydroxylase which plays an important role in converting dietary vitamin D to active metabolite, 25-(OH)D3. We identified high levels of CYP2R1 expression using tissue microarray of human OSCC tumor specimens compared to normal adjacent tissue. Therefore, we hypothesize that 1,25(OH)2D3 regulates CYP2R1 gene expression in OSCC tumor cells. Interestingly, real-time RT-PCR analysis of total RNA isolated from OSCC cells (SCC1, SCC11B, and SCC14a) treated with 1,25(OH)2D3 showed a significant increase in CYP2R1 and vitamin D receptor (VDR) mRNA expression. Also, Western blot analysis demonstrated that 1,25(OH)2D3 treatment time-dependently increased CYP2R1 expression in these cells. 1,25(OH)2D3 stimulation of OSCC cells transiently transfected with the hCYP2R1 promoter (-2kb)-luciferase reporter plasmid demonstrated a 4.3-fold increase in promoter activity. In addition, 1,25(OH)2D3 significantly increased c-Fos, p-c-Jun expression, and c-Jun N-terminal kinase (JNK) activity in these cells. The JNK inhibitor suppresses 1,25(OH)2D3, inducing CYP2R1 mRNA expression and gene promoter activity in OSCC cells. Furthermore, JNK inhibitor significantly decreased 1,25(OH)2D3 inhibition of OSCC tumor cell proliferation. Taken together, our results suggest that AP-1 is a downstream effector of 1,25(OH)2D3 signaling to modulate CYP2R1 gene expression in OSCC tumor cells, and vitamin D analogs could be potential therapeutic agents to control OSCC tumor progression.

Cancer-Derived Mutations in KEAP1 Impair NRF2 Degradation but not Ubiquitination

NRF2 is a transcription factor that mediates stress responses. Oncogenic mutations in NRF2 localize to one of its two binding interfaces with KEAP1, an E3 ubiquitin ligase that promotes proteasome-dependent degradation of NRF2. Somatic mutations in KEAP1 occur commonly in human cancer, where KEAP1 may function as a tumor suppressor. These mutations distribute throughout the KEAP1 protein but little is known about their functional impact. In this study, we characterized 18 KEAP1 mutations defined in a lung squamous cell carcinoma tumor set. Four mutations behaved as wild-type KEAP1, thus are likely passenger events. R554Q, W544C, N469fs, P318fs, and G333C mutations attenuated binding and suppression of NRF2 activity. The remaining mutations exhibited hypomorphic suppression of NRF2, binding both NRF2 and CUL3. Proteomic analysis revealed that the R320Q, R470C, G423V, D422N, G186R, S243C, and V155F mutations augmented the binding of KEAP1 and NRF2. Intriguingly, these "super-binder" mutants exhibited reduced degradation of NRF2. Cell-based and in vitro biochemical analyses demonstrated that despite its inability to suppress NRF2 activity, the R320Q "superbinder" mutant maintained the ability to ubiquitinate NRF2. These data strengthen the genetic interactions between KEAP1 and NRF2 in cancer and provide new insight into KEAP1 mechanics.

Morphometry in the cytological diagnosis of cervical smears.

Morphometry of cells found in normal and abnormal smears taken from the vagina and the uterine cervix is the assessment of the size and diameter of their nuclei. The values of these quantities provide information on the origin of these cells and the degree of possible anomalies. Determining the morphometric traits of different types of cells found in the cervix and the uterus is a very important element in the diagnosis of disorders that often lead to cervical tumors. The aim of this research is to determine the morphometric characteristics of cells found in cervical smears by measuring the cell circumference, the diameter of the nucleus and the cell surface areain order to identify which clinical group the cells belong to, which facilitates diagnosis. The study material consisted of cervical smears that demonstrated the presence of cells in various phases of the clinical Bethesda classification. For each clinical classification, the values of the cell circumference, the cell surface area and the diameter of the nucleus were measured for 100 cells. The largest cells are normal cells in the surface layer. In relation to these cells, the atrophic cells from the groups containing atypical squamous cells of undetermined significance (ASC-US), low-grade squamous intraepithelial lesions (LSIL), high-grade squamous intraepithelial lesion (HSIL) and tumor cells tend to decrease in size, with small variations. Considering the mean values of the parameters analyzed, the cells of the LSIL group are larger than those from the ASC-US group. According to the mean values, normal cells have the smallest nucleus and the HSIL cells and tumor cells have the largest. The statistical analysis shows significant differences between the morphometric traits in the different clinical groups, which indicates that morphometry can be used in cytological diagnosis.