Gabor Tarjan

Gastroesophageal Reflux Disease (GERD): Is There More to the Story?

Gastroesophageal reflux disease (GERD) affects both men and women worldwide, with the most common symptom of GERD being frequent heartburn. If left untreated, more serious diseases including esophagitis and/or esophageal cancer may result. GERD has been commonly held to be the result of gastric acid refluxing into the esophagus. Recent work, however, has shown that there are acid‐producing cells in the upper aerodigestive tract. In addition, acid‐producing bacteria located within the upper gastrointestinal tract and oral cavity may also be a contributing factor in the onset of GERD. Proton pump inhibitors (PPIs) are commonly prescribed for treating GERD; these drugs are designed to stop the production of gastric acid by shutting down the H+/K+‐ATPase enzyme located in parietal cells. PPI treatment is systemic and therefore significantly different than traditional antacids. Although a popular treatment choice, PPIs exhibit substantial interpatient variability and commonly fail to provide a complete cure to the disease. Recent studies have shown that H+/K+‐ATPases are expressed in tissues outside the stomach, and the effects of PPIs in these nongastric tissues have not been fully explored. Likewise, acid‐producing bacteria containing proton pumps are present in both the oral cavity and esophagus, and PPI use may also adversely affect these bacteria. The use of PPI therapy is further complicated by the two philosophical approaches to treating this disease: to treat only symptoms or to treat continuously. The latter approach frequently results in unwanted side effects which may be due to the PPIs acting on nongastric tissues or the microbes which colonize the upper aerodigestive tract.

Part I. Molecular and cellular characterization of high nitric oxide-adapted human breast adenocarcinoma cell lines

There is a lack of understanding of the casual mechanisms behind the observation that some breast adenocarcinomas have identical morphology and comparatively different cellular growth behavior. This is exemplified by a differential response to radiation, chemotherapy, and other biological intervention therapies. Elevated concentrations of the free radical nitric oxide (NO), coupled with the up-regulated enzyme nitric oxide synthase (NOS) which produces NO, are activities which impact tumor growth. Previously, we adapted four human breast cancer cell lines: BT-20, Hs578T, T-47D, and MCF-7 to elevated concentrations of nitric oxide (or high NO [HNO]). This was accomplished by exposing the cell lines to increasing levels of an NO donor over time. Significantly, the HNO cell lines grew faster than did each respective (“PARENT”) cell line even in the absence of NO donor-supplemented media. This was evident despite each “parent” being morphologically equivalent to the HNO adapted cell line. Herein, we characterize the HNO cells and their biological attributes against those of the parent cells. Pairs of HNO/parent cell lines were then analyzed using a number of key cellular activity criteria including: cell cycle distribution, DNA ploidy, response to DNA damage, UV radiation response, X-ray radiation response, and the expression of significant cellular enzymes. Other key enzyme activities studied were NOS, p53, and glutathione S-transferase-pi (GST-pi) expression. HNO cells were typified by a far more aggressive pattern of growth and resistance to various treatments than the corresponding parent cells. This was evidenced by a higher S-phase percentage, variable radioresistance, and up-regulated GST-pi and p53. Taken collectively, this data provides evidence that cancer cells subjected to HNO concentrations become resistant to free radicals such as NO via up-regulated cellular defense mechanisms, including p53 and GST-pi. The adaptation to NO may explain how tumor cells acquire a more aggressive tumor phenotype.

Part I. Development of a model system for studying nitric oxide in tumors: high nitric oxide-adapted head and neck squamous cell carcinoma cell lines

The free radical nitric oxide (NO) is over-expressed in many tumors, including head and neck squamous cell carcinomas (HNSCC); however, the role NO plays in tumor pathophysiology is still not well understood. We, herein, report the development of an in vitro model system which can be used to probe the role of NO in the carcinogenesis of HNSCC. Five HNSCC cell lines were adapted to a high NO (HNO) environment by gradually introducing increasing concentrations of DETA-NONOate, a nitrogen-based NO donor, to cell media. The adaptation process was carried out until a sufficiently high enough donor concentration was reached which enabled the HNO cells to survive and grow, but which was lethal to the original, unadapted (“parent”) cells. The adapted HNO cells exhibited analogous morphology to the parent cells, but grew better than their corresponding parent cells in normal media, on soft agar, and in the presence of hydrogen peroxide, an oxygen-based free radical donor. These results indicate that the HNO cell lines are unique and possess biologically different properties than the parent cell lines from which they originated. The HNO/parent cell lines developed herein may be used as a model system to better understand the role NO plays in HNSCC carcinogenesis.

Part II. Initial molecular and cellular characterization of high nitric oxide-adapted human tongue squamous cell carcinoma cell lines

It is not understood why some head and neck squamous cell carcinomas, despite having identical morphology, demonstrate different tumor aggressiveness, including radioresistance. High levels of the free radical nitric oxide (NO) and increased expression of the NO-producing enzyme nitric oxide synthase (NOS) have been implicated in tumor progression. We previously adapted three human tongue cancer cell lines to high NO (HNO) levels by gradually exposing them to increasing concentrations of an NO donor; the HNO cells grew faster than their corresponding untreated (“parent”) cells, despite being morphologically identical. Herein we initially characterize the HNO cells and compare the biological properties of the HNO and parent cells. HNO/parent cell line pairs were analyzed for cell cycle distribution, DNA damage, X-ray and ultraviolet radiation response, and expression of key cellular enzymes, including NOS, p53, glutathione S-transferase-pi (GST-pi), apurinic/apyrimidinic endonuclease-1 (APE1), and checkpoint kinases (Chk1, Chk2). While some of these properties were cell line-specific, the HNO cells typically exhibited properties associated with a more aggressive behavior profile than the parent cells (greater S-phase percentage, radioresistance, and elevated expression of GST-pi/APE1/Chk1/Chk2). To correlate these findings with conditions in primary tumors, we examined the NOS, GST-pi, and APE1 expression in human tongue squamous cell carcinomas. A majority of the clinical samples exhibited elevated expression levels of these enzymes. Together, the results herein suggest cancer cells exposed to HNO levels can develop resistance to free radicals by upregulating protective mechanisms, such as GST-pi and APE1. These upregulated defense mechanisms may contribute to their aggressive expression profile.

Long-term adaptation of the human lung tumor cell line A549 to increasing concentrations of hydrogen peroxide

Previously, we demonstrated that A549, a human lung cancer cell line, could be adapted to the free radical nitric oxide (NO●). NO● is known to be over expressed in human tumors. The original cell line, A549 (parent), and the newly adapted A549-HNO (which has a more aggressive phenotype) serve as a useful model system to study the biology of NO●. To see if tumor cells can similarly be adapted to any free radical with the same outcome, herein we successfully adapted A549 cells to high levels of hydrogen peroxide (HHP). A549-HHP, the resulting cell line, was more resistant and grew better then the parent cell line, and showed the following characteristics: (1) resistance to hydrogen peroxide, (2) resistance to NO●, (3) growth with and without hydrogen peroxide, and (4) resistance to doxorubicin. Gene chip analysis was used to determine the global gene expression changes between A549-parent and A549-HHP and revealed significant changes in the expression of over 1,700 genes. This gene profile was markedly different from that obtained from the A549-HNO cell line. The mitochondrial DNA content of the A549-HHP line determined by quantitative PCR favored a change for a more anaerobic metabolic profile. Our findings suggest that any free radical can induce resistance to other free radicals; this is especially important given that radiation therapy and many chemotherapeutic agents exert their effect via free radicals. Utilizing this model system to better understand the role of free radicals in tumor biology will help to develop new therapeutic approaches to treat lung cancer.

Encapsulated follicular variant of papillary thyroid carcinoma/noninvasive follicular thyroid neoplasm with papillary-like nuclear features with Spindle Cell Metaplasia: Case report and review of literature

Spindle cell lesions of the thyroid are rare overall, and span a wide clinical spectrum that ranges from spindle cell metaplasia (SCM1) to anaplastic carcinoma. Their differentiation is only seldom straightforward, and usually requires the integration of the clinical, histological and immunohistochemical data. Only a handful of publications have described cases of SCM in the thyroid and we add to that literature by reporting a unique case of encapsulated follicular variant of papillary thyroid carcinoma/noninvasive follicular thyroid neoplasm with papillary-like nuclear features with SCM. In addition, we review the literature on the relationship between SCM and different thyroid lesions, summarizing the morphological and immunohistochemical features that aid in its differentiation from more aggressive spindle cell proliferations.

Cytopathology of Head and Neck Lesions

Cytopathology is the morphologic study of diseased cells. The diagnosis is based on the microscopic appearance of cells, sometimes with intercellular material, dispersed on glass slides. Cells from lesions in the head and neck (H&N) region are generally collected by fine needle aspiration (FNA). FNA is an outpatient procedure that does not require anesthesia, is minimally discomforting to the patient, and has rapid turnaround time. In the hands of experienced individuals, FNA is highly sensitive and specific. Of all potential FNA sites, the H&N area is one of the most complex, since it includes a number of different structures (various types of lining epithelium, exocrine and endocrine glands, lymphoid organs, etc.) from which both benign and malignant tumors may arise. The most common diseases of the three frequently aspirated H&N sites (salivary glands, thyroid, and cervical lymph nodes) are the main focus of this chapter. Important cytological mimics of these mainly neoplastic lesions are also included. Microscopic photographs of representative cases illustrate the majority of the discussed diseases. In the photographs, cytological and histological features of the same lesions are presented side by side to facilitate an understanding of the cytological characteristics. Current trends to use FNA to test for molecular biomarkers of diagnostic and prognostic value are also discussed.

Succinate Dehydrogenase Complex

Succinate dehydrogenase (SDH) is uniquely tasked with a dual role in the essential energy-producing processes of a cell. Although SDH subunits and assembly factors form part of the same enzyme complex, mutations in their respective genes lead to significantly different clinical phenotypes. Remarkable discoveries in the last 17 years have led to the delineation of the SDH complex deficiency syndrome and its multiple pathogenic branches. Here we provide an updated overview of SDH deficiency in order to raise awareness of its multiple connotations including nonneoplastic associations and pertinent features of the continually growing list of SDH-mutant tumors so as to better direct genetic counseling and predict prognosis.

Sarcoidosis in an Endometrial Polyp

Endometrial sarcoidosis is one of the rarest forms of extrapulmonary sarcoidosis, with less than 35 cases ever being reported in the English medical literature. Furthermore, uterine sarcoidosis coexisting with an endometrial polyp has never been previously reported. A 60-year-old postmenopausal Hispanic woman presented complaining of intermittent pelvic pain. Her past medical history was notable for an incidental computed tomography (CT) scan finding of 2 noncalcified pulmonary nodules about 4 years prior. A repeat CT scan 3 months later revealed calcified mediastinal and left hilar lymph nodes, with no focal pulmonary nodules, and a third CT scan 3.5 years later reidentified the pulmonary nodules without increase in size and stable calcified mediastinal and left hilar lymph nodes. A pelvic ultrasound to evaluate her current pelvic pain revealed an uterine fibroid and thickened endometrial stripe measuring 8.7 mm with increased vascularity. Given the findings, a hysteroscopy and endometrial curetting was performed. During the procedure, a firm-appearing polypoid structure was identified attached to the uterine fundus, which was resected and submitted to pathology along with the endometrial curetting. Microscopic examination revealed a polypoid structure (Figure 1) containing large thick-walled vessels and surrounded by cystically dilated weakly proliferative endometrial glands (Figure 2). Embedded in the benign appearing endometrial stroma were multiple noncaseating granulomas composed of lymphocytes, epithelioid macrophages, and multinucleated giant cells (Figure 3). Within the cytoplasm of some of these multinucleated cells were polarizable colorless crystalline inclusions, occasionally with foci of early Schaumann (conchoidal) bodies forming around them (Figure 4). Ziehl-Neelsen stain was negative for mycobacteria, and Gomori methenamine silver stain was negative for fungal organisms. These histological findings are compatible with an endometrial polyp involved by sarcoidosis. Endometrial involvement by sarcoidosis is commonly associated with concurrent involvement of other organs, such as eyes and lungs. Rarely though, endometrial sarcoidosis may present as a polypoid lesion as a result of the endometrial sarcoid granulomas rather than a true histologic endometrial polyp. Colorless birefringent crystals or inclusions have long been identified in sarcoid granulomas. They consist predominantly of calcium oxalate, originate in the macrophages, and are precursors to other 673908 IJSXXX10.1177/1066896916673908International Journal of Surgical PathologyHaroon Al Rasheed et al research-article2016

Renal Angiomyolipoma With Sarcoid Granulomas Report of a Unique Case

Angiomyolipoma is a mesenchymal neoplasm characterized by the coexpression of melanocytic and smooth muscle markers. Sarcoidosis is a multisystem disorder of unknown etiology, which presents with characteristic nonnecrotizing granulomas and rarely involves the kidney. The coexistence of renal sarcoidosis with renal neoplasms is exceedingly rare and was reported only with renal cell carcinoma. Renal sarcoidosis associated with a nonepithelial renal neoplasm, such as an angiomyolipoma has never been reported. We present the first reported case of sarcoid granulomas in a renal angiomyolipoma, including morphologic and immunohistochemical features.