Songlin Zhang

NSD3-NUT Fusion Oncoprotein in NUT Midline Carcinoma: Implications for a Novel Oncogenic Mechanism

UNLABELLEDnNUT midline carcinoma (NMC) is an aggressive subtype of squamous cell carcinoma that typically harbors BRD4/3-NUT fusion oncoproteins that block differentiation and maintain tumor growth. In 20% of cases, NUT is fused to uncharacterized non-BRD gene(s). We established a new patient-derived NMC cell line (1221) and demonstrated that it harbors a novel NSD3-NUT fusion oncogene. We find that NSD3-NUT is both necessary and sufficient for the blockade of differentiation and maintenance of proliferation in NMC cells. NSD3-NUT binds to BRD4, and BRD bromodomain inhibitors induce differentiation and arrest proliferation of 1221 cells. We find further that NSD3 is required for the blockade of differentiation in BRD4-NUT-expressing NMCs. These findings identify NSD3 as a novel critical oncogenic component and potential therapeutic target in NMC.nnnSIGNIFICANCEnThe existence of a family of fusion oncogenes in squamous cell carcinoma is unprecedented, and should lead to key insights into aberrant differentiation in NMC and possibly other squamous cell carcinomas. The involvement of the NSD3 methyltransferase as a component of the NUT fusion protein oncogenic complex identifies a new potential therapeutic target.

Aggressive mammary carcinoma progression in Nrf2 knockout mice treated with 7,12-dimethylbenz[a]anthracene.

BackgroundActivation of nuclear factor erythroid 2-related factor (Nrf2), which belongs to the basic leucine zipper transcription factor family, is a strategy for cancer chemopreventive phytochemicals. It is an important regulator of genes induced by oxidative stress, such as glutathione S-transferases, heme oxygenase-1 and peroxiredoxin 1, by activating the antioxidant response element (ARE). We hypothesized that (1) the citrus coumarin auraptene may suppress premalignant mammary lesions via activation of Nrf2/ARE, and (2) that Nrf2 knockout (KO) mice would be more susceptible to mammary carcinogenesis.MethodsPremalignant lesions and mammary carcinomas were induced by medroxyprogesterone acetate and 7,12-dimethylbenz[a]anthracene treatment. The 10-week pre-malignant study was performed in which 8 groups of 10 each female wild-type (WT) and KO mice were fed either control diet or diets containing auraptene (500 ppm). A carcinogenesis study was also conducted in KO vs. WT mice (n = 30-34). Comparisons between groups were evaluated using ANOVA and Kaplan-Meier Survival statistics, and the Mann-Whitney U-test.ResultsAll mice treated with carcinogen exhibited premalignant lesions but there were no differences by genotype or diet. In the KO mice, there was a dramatic increase in mammary carcinoma growth rate, size, and weight. Although there was no difference in overall survival, the KO mice had significantly lower mammary tumor-free survival. Also, in the KO mammary carcinomas, the active forms of NF-κB and β-catenin were increased ~2-fold whereas no differences in oxidized proteins were observed. Many other tumors were observed, including lymphomas. Interestingly, the incidences of lung adenomas in the KO mice were significantly higher than in the WT mice.ConclusionsWe report, for the first time, that there was no apparent difference in the formation of premalignant lesions, but rather, the KO mice exhibited rapid, aggressive mammary carcinoma progression.

Thin core needle biopsy crush preparations in conjunction with fine-needle aspiration for the evaluation of thyroid nodules: a complementary approach.

Fine‐needle aspiration (FNA) is widely accepted as the initial test to evaluate thyroid nodules; however, inadequate and suboptimal specimens have been 1 of its limitations. Unsatisfactory rates of 4.1% to 43% have been reported, but suboptimal specimens with adequate epithelial cells and other limiting factors, such as clotting, often are not addressed. The authors institution has a low unsatisfactory rate, especially for thyroid biopsies performed under ultrasound in the Interventional Radiology (IR) Department. In addition to on‐site evaluation for all cases, they concomitantly use thin, 22/20‐gauge core needle biopsy (CB) crush preparations (CP) for unsatisfactory/suboptimal FNAs. The CB usually is done after 2 FNA passes and, in most cases, is exhausted by making an air‐dried CP, which is evaluated on site for adequacy; any residual tissue is processed for tissue sections. Experience is required to interpret CP on air‐dried smears. In this report, the authors describe a complementary approach to thyroid biopsy that has worked well.

Changing trends in human papillomavirus-associated head and neck squamous cell carcinoma

Head and neck squamous cell carcinoma (HNSCC) continues to be a significant disease with varying rates of incidence and mortality worldwide. Numerous studies have demonstrated that human papillomavirus (HPV) is etiologically linked with a subset of HNSCC, independent of tobacco and alcohol use. This subset of tumor shows increased sensitivity to radiation therapy and association with better outcomes. The study aims to determine the HPV burden and trend among patients with HNSCC in the southern region of the United States over the past 10 years. Of 142 cases from 2000 to 2004, 18 (13%) were positive for high-risk HPV. Nine of these were oropharyngeal tumors, including 4 cases from the tonsil. These constitute 38% (9/24) of all oropharyngeal tumors and 57% (4/7) of tonsillar tumors. Of 35 cases from 2009 to 2010, 14 (40%) were positive for high-risk HPV. Thirteen of these were oropharyngeal tumors, including 9 cases from the tonsil. These constitute 59% (13/23) of oropharyngeal tumors and 64% (9/14) of tonsillar tumors. When data from the 2 periods are combined, the results show that African American patients are less likely to have HPV-associated disease compared with white patients (9% vs 22%). Human papillomavirus-positive and oropharyngeal HNSCC are more likely to be nonkeratinizing (P < .0001). In conclusion, the HPV detection rate in oropharyngeal squamous cell carcinoma increased from 38% to 59% between the 2000-to-2004 and 2009-to-2010 periods.

The role of routine immunohistochemistry for Helicobacter pylori in gastric biopsy

Helicobacter pylori infection is associated with gastritis, gastric ulcer, gastric adenocarcinoma, and mucosal associated lymphoid tissue lymphoma. Documenting the presence of H pylori in a gastric biopsy is essential for appropriate patient care. Several special stains and immunohistochemistry (IHC) stain for H pylori are available, and many laboratories are routinely using one of them. We introduced routine IHC for H pylori about a year ago, and this study aims to investigate the value of this protocol. A total of 224 patients qualified for the study criteria during this period. The diagnoses were chronic active gastritis (68), chronic gastritis (76), no pathologic abnormality (50), reactive gastropathy (24), and polyps (6). Fifty-four cases were positive for H pylori on IHC, including 50 chronic active gastritis and 4 chronic gastritis. The IHC positive rate was 73.5% (50/68) in chronic active gastritis, 5.3% (4/76) in chronic gastritis, and 0% (0/80) in other diagnoses. The sensitivity/specificity of finding H pylori by blindly reviewing hematoxylin and eosin slides was 100%/100%, 100%/100%, 95%/100%, and 100%/100% from the 4 authors. Our results showed that many gastric biopsies (35.7%, 80/224) had no pathologic abnormality or reactive gastropathy and did not need a routine IHC for H pylori. Hematoxylin and eosin slide review had a very good sensitivity and specificity with all levels of observers. In summary, IHC for H pylori should not be routinely used, especially during these economically challenging times. Immunohistochemistry should be reserved for unexplained gastritis and previously treated patients with likely low organism density.

Fine needle aspiration of salivary glands: 5-Year experience from a single academic center

OBJECTIVEnTo investigate 5 years experience with fine needle aspiration (FNA) of salivary glands at a single academic center.nnnSTUDY DESIGNnA total of 191 salivary gland FNAs were performed at Louisiana State University Health Science Center from 2003 to 2007, and all were done on major salivary glands except for 1 case.nnnRESULTSnThe cytologic diagnoses included 17 malignancies, 6 atypia, 73 neoplasms, 87 negative and 18 nondiagnostic. Eighty-six cases had histologic follow-up (45.0%). There were 5 false negatives: 2 adenoid cystic carcinomas, 1 acinic cell carcinoma, 1 polymorphous low grade adenocarcinoma and 1 metastatic basaloid squamous cell carcinoma. The only false positive was a pleomorphic adenoma misdiagnosed as adenoid cystic carcinoma. Four reactive processes were diagnosed as benign neoplasms, including 2 granulomatous inflammation and 2 chronic sialadenitis. Five benign neoplasms were interpreted as reactive processes, including 2 Warthins tumors, 2 sebaceous lymphoadenomas and 1 pleomorphic adenoma. The overall accuracy in distinguishing benign from malignant lesions was 79.1%, and the sensitivity for salivary neoplasia was 89.4%.nnnCONCLUSIONnOur results are consistent with the literature that salivary gland FNA has good sensitivity, specificity and accuracy in the diagnosis of salivary neoplasms. FNA can play a significant role in triaging patients with onsite cytologic interpretation and can reduce many unnecessary surgeries.

The role of fluorescence in situ hybridization and polymerase chain reaction in the diagnosis and classification of lymphoproliferative disorders on fine-needle aspiration

Fine‐needle aspiration (FNA) has been used in the evaluation of lymphadenopathy for a long time and is highly reliable in the identification of metastatic malignancies. However, the role of FNA in the assessment of new lymphoproliferative disorders continues to be a subject of debate. The objective of the current study was to evaluate the role of molecular cytogenetic studies in FNA diagnoses of lymphoproliferative disorders.

The diagnostic value of cell block as an adjunct to liquid-based cytology of bronchial washing specimens in the diagnosis and subclassification of pulmonary neoplasms

To the authors knowledge, the diagnostic value of cell block (CB) as an adjunct to ThinPrep liquid‐based cytology (LBC) of bronchial washing specimens in the detection and subclassification of pulmonary neoplasms has not been well evaluated. The objective of the current study was to evaluate the diagnostic utility of CB in this setting.

Papillary oncocytic cystadenoma of the parotid glands: a report of 2 cases with varied cytologic features.

BACKGROUNDnPapillary cystadenoma is a rare salivary gland neoplasm, and oncocytic change can be focal or marked. Papillary oncocytic cystadenoma has been reported mainly in the minor salivary glands and occasionally in the parotid glands. The cytologic features vary.nnnCASESnA 26-year-old female presented with a 2.4-cm, cystic right parotid gland mass present for 4 months. Fine needle aspiration (FNA) showed cellular smears with sheets of oncocytic cells and some with micropapillary architecture. The diagnosis ofa neoplasm was rendered and excisional biopsy recommended. Oncocytic neoplasm was diagnosed during intraoperative consultation, and final surgical histology showed a unilocular, cystic, oncocytic neoplasm with variable papillary projections. A 52-year-old male presented with a 1.5-cm, cystic left parotid mass enlarging for the past few months. FNA showed less cellular smears with extensive necrotic debris and a few large sheets of epithelial cells with vague papillary architecture. Oncocytic neoplasm was diagnosed during intraoperative consultation, and final surgical histology showed a unilocular cystic lesion with multiple papillary fronds lined with oncocytic cells and focal metaplastic squamous cells.nnnCONCLUSIONnPapillary cystadenoma is rare in the parotid glands, and cytologic features may vary. Warthins tumor, oncocytoma, intraductal papilloma and acinic cell carcinoma may arise in the differential diagnosis. In cases with extensive necrotic debris and metaplastic squamous cells, branchial cyst and cystic metastatic squamous carcinoma may also need to be considered.

A novel therapeutic strategy to rescue the immune effector function of proteolytically-inactivated cancer therapeutic antibodies

Primary and acquired resistance to anticancer antibody immunotherapies presents significant clinical challenges. Here, we demonstrate that proteolytic inactivation of cancer-targeting antibodies is an unappreciated contributor to cancer immune evasion, and the finding presents novel opportunities for therapeutic intervention. A single peptide bond cleavage in the IgG1 hinge impairs cancer cell killing due to structural derangement of the Fc region. Hinge-cleaved trastuzumab gradually accumulated on the surfaces of HER2-expressing cancer cell lines in vitro, and was greatly accelerated when the cells were engineered to express the potent bacterial IgG-degrading proteinase (IdeS). Similar to cancer-related matrix metalloproteinases (MMP), IdeS exposes a hinge neoepitope that we have developed an antibody, mAb2095-2, to specifically target the epitope. In in vitro studies, mAb2095-2 restored the lost antibody-dependent cell-mediated cytotoxicity functionality of cell-bound single-cleaved trastuzumab (scIgG-T). In vivo, mAb2095-2 rescued the impaired Fc-dependent tumor-suppressive activity of scIgG-T in a xenograft tumor model and restored the recruitment of immune effector cells into the tumor microenvironment. More importantly, an Fc-engineered proteinase-resistant version of mAb2095-2 rescued trastuzumab antitumor efficacy in a mouse tumor model with human cancer cells secreting IdeS, whereas trastuzumab alone showed significantly reduced antitumor activity in the same model. Consistently, an Fc-engineered proteinase-resistant version of trastuzumab also greatly improved antitumor efficacy in the xenograft tumor model. Taken together, these findings point to a novel cancer therapeutic strategy to rescue proteolytic damage of antibody effector function by an Fc-engineered mAb against the hinge neoepitope and to overcome cancer evasion of antibody immunity. Mol Cancer Ther; 14(3); 681–91. ©2014 AACR.