MicroRNA 4423 is a primate-specific regulator of airway epithelial cell differentiation and lung carcinogenesis.

Smoking is a significant risk factor for lung cancer, the leading cause of cancer-related deaths worldwide. Although microRNAs are regulators of many airway gene-expression changes induced by smoking, their role in modulating changes associated with lung cancer in these cells remains unknown. Here, we use next-generation sequencing of small RNAs in the airway to identify microRNA 4423 (miR-4423) as a primate-specific microRNA associated with lung cancer and expressed primarily in mucociliary epithelium. The endogenous expression of miR-4423 increases as bronchial epithelial cells undergo differentiation into mucociliary epithelium in vitro, and its overexpression during this process causes an increase in the number of ciliated cells. Furthermore, expression of miR-4423 is reduced in most lung tumors and in cytologically normal epithelium of the mainstem bronchus of smokers with lung cancer. In addition, ectopic expression of miR-4423 in a subset of lung cancer cell lines reduces their anchorage-independent growth and significantly decreases the size of the tumors formed in a mouse xenograft model. Consistent with these phenotypes, overexpression of miR-4423 induces a differentiated-like pattern of airway epithelium gene expression and reverses the expression of many genes that are altered in lung cancer. Together, our results indicate that miR-4423 is a regulator of airway epithelium differentiation and that the abrogation of its function contributes to lung carcinogenesis.

Doxycycline reduces fibril formation in a transgenic mouse model of AL amyloidosis.

Systemic AL amyloidosis results from the aggregation of an amyloidogenic immunoglobulin (Ig) light chain (LC) usually produced by a plasma cell clone in the bone marrow. AL is the most rapidly fatal of the systemic amyloidoses, as amyloid fibrils can rapidly accumulate in tissues including the heart, kidneys, autonomic or peripheral nervous systems, gastrointestinal tract, and liver. Chemotherapy is used to eradicate the cellular source of the amyloidogenic precursor. Currently, there are no therapies that target the process of LC aggregation, fibril formation, or organ damage. We developed transgenic mice expressing an amyloidogenic λ6 LC using the cytomegalovirus (CMV) promoter to circumvent the disruption of B cell development by premature expression of recombined LC. The CMV-λ6 transgenic mice develop neurologic dysfunction and Congophilic amyloid deposits in the stomach. Amyloid deposition was inhibited in vivo by the antibiotic doxycycline. In vitro studies demonstrated that doxycycline directly disrupted the formation of recombinant LC fibrils. Furthermore, treatment of ex vivo LC amyloid fibrils with doxycycline reduced the number of intact fibrils and led to the formation of large disordered aggregates. The CMV-λ6 transgenic model replicates the process of AL amyloidosis and is useful for testing the antifibril potential of orally available agents.

Amyloidosis of the gastrointestinal tract: a 13-year, single-center, referral experience.

Amyloidosis of the gastrointestinal tract, with biopsy-proven disease, is rare. We reviewed a series of patients who presented with biopsy-proven gastrointestinal amyloidosis and report their clinical characteristics, treatments, and survival. This is a retrospective review of data prospectively collected from January 1998 to December 2011 in a tertiary referral center; 2,334 patients with all types of amyloidosis were evaluated during this period. Seventy-six patients (3.2%) had biopsy-proven amyloid involvement of the gastrointestinal tract. Their median age was 61 years (range, 34-79). Systemic amyloidosis with dominant gastrointestinal involvement was present in 60 (79%) patients, whereas the other 16 (21%) patients had amyloidosis localized to the gastrointestinal tract without evidence of an associated plasma cell dyscrasia or other organ involvement. Of the 60 systemic cases, 50 (83%) had immunoglobulin light-chain, five (8%) had familial lysozyme, three (5%) had wild-type transthyretin, and two (3%) had mutant transthyretin amyloidosis. The most frequent symptoms for all patients were weight loss in 33 (45%) and gastrointestinal bleeding in 27 (36%). Incidental identification of amyloidosis on routine endoscopic surveillance played a role in the diagnosis of seven patients with systemic immunoglobulin light-chain, and four patients with immunoglobulin light-chain localized to the gastrointestinal tract. Amyloid protein subtyping was performed in 12 of the cases of localized disease, and all had lambda light chain disease. Of the 50 patients with systemic immunoglobulin light-chain amyloidosis, 45 were treated with anti-plasma cell therapy. The median survival has not been reached for this group. For the 16 patients with localized gastrointestinal amyloidosis, supportive care was the mainstay of treatment; none received anti-plasma cell therapy. All 16 are alive at a median follow-up of 36 months (range, 1-143). Patients with biopsy-proven gastrointestinal amyloidosis often present with weight loss and bleeding. In localized cases, all that underwent typing were due to lambda light chain amyloidosis and none progressed to systemic disease during the period of follow-up. Most patients with systemic disease had immunoglobulin light-chain, and their tolerance of therapy and median survival were excellent. Although a rare manifestation of amyloidosis, staining for amyloid should be considered in patients undergoing gastrointestinal biopsy who have unexplained chronic gastrointestinal symptoms.

Amyloid deposits in the bone marrow of patients with immunoglobulin light chain amyloidosis do not impact stem cell mobilization or engraftment.

Amyloid deposits are often found in the bone marrow in patients with Immunoglobulin light chain (AL) amyloidosis. We sought to determine whether this affects stem cell collection or engraftment after high-dose melphalan and autologous stem cell transplantation (HDM-SCT). We reviewed data on 361 patients with AL amyloidosis who had Congo red staining of pretreatment bone marrow biopsy specimens and underwent HDM-SCT between July 1994 and December 2011. We analyzed data on stem cell yield, days of stem cell collection, and days to neutrophil and platelet engraftment posttransplantation. Bone marrow amyloid deposits were found in 65% of patients (n = 233). There were no significant differences in median number of stem cells collected and days to neutrophil or platelet engraftment between patients with bone marrow amyloid deposits and those without these deposits. Thus, our data indicate that although amyloid involvement of the bone marrow is common, it does not negatively affect stem cell mobilization or neutrophil and platelet engraftment after HDM-SCT.

Increased PEA3/E1AF and decreased Net/Elk-3, both ETS proteins, characterize human NSCLC progression and regulate caveolin-1 transcription in Calu-1 and NCI-H23 NSCLC cell lines.

Caveolin-1 protein has been called a 'conditional tumor suppressor' because it can either suppress or enhance tumor progression depending on cellular context. Caveolin-1 levels are dynamic in non-small-cell lung cancer, with increased levels in metastatic tumor cells. We have shown previously that transactivation of an erythroblastosis virus-transforming sequence (ETS) cis-element enhances caveolin-1 expression in a murine lung epithelial cell line. Based on high sequence homology between the murine and human caveolin-1 promoters, we proposed that ETS proteins might regulate caveolin-1 expression in human lung tumorigenesis. We confirm that caveolin-1 is not detected in well-differentiated primary lung tumors. Polyoma virus enhancer activator 3 (PEA3), a pro-metastatic ETS protein in breast cancer, is expressed at low levels in well-differentiated tumors and high levels in poorly differentiated tumors. Conversely, Net, a known ETS repressor, is expressed at high levels in the nucleus of well-differentiated primary tumor cells. In tumor cells in metastatic lymph node sites, caveolin-1 and PEA3 are highly expressed, whereas Net is now expressed in the cytoplasm. We studied transcriptional regulation of caveolin-1 in two human lung cancer cell lines, Calu-1 (high caveolin-1 expressing) and NCI-H23 (low caveolin-1 expressing). Chromatin immunoprecipitation-binding assays and small interfering RNA experiments show that PEA3 is a transcriptional activator in Calu-1 cells and that Net is a transcriptional repressor in NCI-H23 cells. These results suggest that Net may suppress caveolin-1 transcription in primary lung tumors and that PEA3 may activate caveolin-1 transcription in metastatic lymph nodes.

Cardiac amyloidosis in African Americans: comparison of clinical and laboratory features of transthyretin V122I amyloidosis and immunoglobulin light chain amyloidosis.

BACKGROUND: Transthyretin (TTR) mutations known to cause cardiac amyloidosis include V122I, found almost exclusively in African Americans at a prevalence of 3-3.9%. This retrospective study describes TTR V122I-associated cardiac amyloid disease (ATTR) in a major amyloid referral clinic population. METHODS: Self-identified African Americans with amyloidosis (n = 156) were screened for TTR V122I by serum isoelectric focusing; mutant TTR was confirmed by DNA sequencing or mass spectrometry. Cardiac findings in ATTR V122I and immunoglobulin light chain (AL) amyloidoses were compared. RESULTS: TTR V122I was identified in 36/156 (23.1%) of evaluated patients and included 5 homozygotes; the allele frequency was 0.013. One compound heterozygote (F44L/V122I) and 4 patients who had AL and the mutant TTR allele were characterized. In patients negative for V122I, AL was the most frequent diagnosis (86/120). Cardiomyopathy was present in 100% of patients with ATTR and 84% of patients with AL (P = .01). In patients with dominant cardiac involvement, better survival occurred in ATTR (n = 30) compared to AL (n = 31), (27 vs 5 months, P < .01) although the mean age in ATTR was higher (70.3 vs 56.2 years, P < .01). Congestive heart failure symptoms and electrocardiographic findings were similar in ATTR and AL, but significant differences in echocardiographic measurements were observed. CONCLUSIONS: ATTR V122I and AL are equally prevalent as the cause of cardiomyopathy in African Americans referred for a diagnosis of amyloidosis. Available therapy for AL underscores the need for early and accurate determination of amyloid type.

Partial inhibition of integrin alpha(v)beta6 prevents pulmonary fibrosis without exacerbating inflammation.

RATIONALE: Transforming growth factor (TGF)-beta has a central role in driving many of the pathological processes that characterize pulmonary fibrosis. Inhibition of the integrin alpha(v)beta6, a key activator of TGF-beta in lung, is an attractive therapeutic strategy, as it may be possible to inhibit TGF-beta at sites of alpha(v)beta6 up-regulation without affecting other homeostatic roles of TGF-beta. OBJECTIVES: To analyze the expression of alpha(v)beta6 in human pulmonary fibrosis, and to functionally test the efficacy of therapeutic inhibition of alpha(v)beta6-mediated TGF-beta activation in murine bleomycin-induced pulmonary fibrosis. METHODS: Lung biopsies from patients with a diagnosis of systemic sclerosis or idiopathic pulmonary fibrosis were stained for alpha(v)beta6 expression. A range of concentrations of a monoclonal antibody that blocks alpha(v)beta6-mediated TGF-beta activation was evaluated in murine bleomycin-induced lung fibrosis. MEASUREMENTS AND MAIN RESULTS: Alpha(v)beta6 is overexpressed in human lung fibrosis within pneumocytes lining the alveolar ducts and alveoli. In the bleomycin model, alpha(v)beta6 antibody was effective in blocking pulmonary fibrosis. At high doses, there was increased expression of markers of inflammation and macrophage activation, consistent with the effects of TGF-beta inhibition in the lung. Low doses of antibody attenuated collagen expression without increasing alveolar inflammatory cell populations or macrophage activation markers. CONCLUSIONS: Partial inhibition of TGF-beta using alpha(v)beta6 integrin antibodies is effective in blocking murine pulmonary fibrosis without exacerbating inflammation. In addition, the elevated expression of alpha(v)beta6, an activator of the fibrogenic cytokine, TGF-beta, in human pulmonary fibrosis suggests that alpha(v)beta6 monoclonal antibodies could represent a promising new therapeutic strategy for treating pulmonary fibrosis.

Metastatic interdigitating dendritic cell sarcoma masquerading as a skin primary tumor: a case report and review of the literature.

We report an unusual case of a lymph node interdigitating dendritic cell sarcoma (IDCS), metastatic to skin, in a 73-year-old patient. The patient initially presented as having a primary skin tumor with lymph node metastasis. The metastatic IDCS was initially read as an atypical fibroxanthoma. However, the morphology seen on the lymph node excision, paired with immunohistochemistry and electron microscopy studies, was diagnostic for an IDCS. Additional immunohistochemistry was performed on the shave biopsy, confirming that the skin tumor was a metastasis. IDCS is a rare tumor that belongs to the histiocytic and dendritic cell group of tumors. Diagnosing this entity is difficult without the aid of ancillary testing such as immunohistochemistry and electron microscopy. In the workup of a spindle cell neoplasm, IDCS should be included in the differential diagnosis.

Unusual tumor response and toxicity from radiation and concurrent erlotinib for non-small-cell lung cancer.

We report a case of a never-smoker female with non-small-cell lung cancer (NSCLC) who experienced a striking tumor response to combined low-dose radiation and the epidermal growth factor receptor inhibitor erlotinib, even though erlotinib alone was not effective in preventing tumor progression. Furthermore, the patient developed symptomatic pneumonitis, which is unusual for the small volume of lung that was exposed to a significant dose of radiation. This case demonstrates that combination therapy with radiation and erlotinib has the potential to significantly benefit a subset of patients with NSCLC in addition to those approximately 10% who have tumors which respond to erlotinib alone. It also highlights the potential risks of molecular targeted radiation therapy.

ETS1 regulates Twist1 transcription in a KrasG12D/Lkb1-/- metastatic lung tumor model of non-small cell lung cancer.

Distinct members of the Ets family of transcription factors act as positive or negative regulators of genes involved in cellular proliferation, development, and tumorigenesis. In human lung cancer, increased ETS1 expression is associated with poor prognosis and metastasis. We tested whether ETS1 contributes to lung tumorigenesis by binding to Twist1, a gene involved in tumor cell motility and dissemination. We used a mouse lung cancer model with metastasis driven by conditionally activated Kras and concurrent tumor suppressor Lkb1 loss (KrasG12D/ Lkb1-/- model) and a similar model of lung cancer that does not metastasize, driven by conditionally activated Kras alone (KrasG12D model). We show that Ets1 and Twist1 gene expression differs between KrasG12D tumors (low Ets1 and Twist1 expression) and KrasG12D/Lkb1-/- tumors (high Ets1 and Twist1 expression). In human lung tumors, ETS1 and TWIST1 expression positively correlates and low combined ETS1 and TWIST1 levels are associated with improved survival compared to high levels. Using mouse cell lines derived from KrasG12D and KrasG12D/Lkb1-/- mouse models and the human lung cancer (A549) cell line, we show that ETS1 regulates Twist1 expression. Chromatin immunoprecipitation assays confirm binding of ETS1 to the Twist1 promoter. Overexpression studies show that ETS1 transactivates Twist1 promoter activity in mouse and human cells. Silencing endogenous Ets1 by siRNA in mouse cell lines decreases Twist1 mRNA levels, decreases invasion, and increases cell growth. Ets1 and Twist1 are at the crossroad of several signaling pathways in cancer. Understanding their regulation may inform the development of therapies to impair lung tumor metastasis.

Endotracheal hamartoma case report: Two contrasting clinical presentations of a rare entity.

INTRODUCTION: The majority of tracheal tumors in adults are malignant. The finding of a benign tumor in the trachea is uncommon and endotracheal hamartomas are rare. PRESENTATION OF CASE: We report two cases presenting within six months at our institution. The first patient is a 67 year-old man who was found to have an asymptomatic endotracheal hamartoma on chest imaging for aortic valve replacement. The second patient is a 46 year-old man with an extensive continued tobacco use disorder and a known endotracheal lesion identified 8 years prior to intervention. Both patients were treated surgically and recovered without complications. DISCUSSION: Identification of these lesions and timely management are necessary because without intervention, they can lead to fatal complications. Most symptoms of tracheal hamartoma result from mechanical obstruction with the earliest presenting symptom being dyspnea, but as evident in these two cases, they can have different presentations. CONCLUSION: We have found that endotracheal hamartoma has a tendency to present in Caucasian, male patients with a comorbidity of respiratory disease and variable smoking history, but it can also present in asymptomatic patients with no significant smoking history.

Transbronchial biopsies safely diagnose amyloid lung disease.

BACKGROUND: Autopsy identifies lung involvement in 58-92% of patients with the most prevalent forms of systemic amyloidoses. In the absence of lung biopsies, amyloid lung disease often goes unrecognized. Report of a death following transbronchial biopsies in a patient with systemic amyloidosis cautioned against the procedure in this patient cohort. We reviewed our experience with transbronchial biopsies in patients with amyloidosis to determine the safety and utility of bronchoscopic lung biopsies. METHODS: We identified patients referred to the Amyloidosis Center at Boston Medical Center with lung amyloidosis diagnosed by transbronchial lung biopsies (TBBX). Amyloid typing was determined by immunohistochemistry or mass spectrometry. Standard end organ assessments, including pulmonary function test (PFT) and chest tomography (CT) imaging, and extra-thoracic biopsies established the extent of disease. RESULTS: Twenty-five (21.7%) of 115 patients with lung amyloidosis were diagnosed by TBBX. PFT classified 33.3% with restrictive physiology, 28.6% with obstructive disease, and 9.5% mixed physiology; 9.5% exhibited isolated diffusion defects while 19% had normal pulmonary testing. Two view chest or CT imaging identified focal opacities in 52% of cases and diffuse interstitial disease in 48%. Amyloid type and disease extent included 68% systemic AL disease, 16% localized (lung limited) AL disease, 12% ATTR disease, and 4% AA amyloidosis. Fluoroscopy was not used during biopsy. No procedure complications were reported. CONCLUSIONS: Our case series of 25 patients supports the use of bronchoscopic transbronchial biopsies for diagnosis of parenchymal lung amyloidosis. Normal PFTs do not rule out the histologic presence of amyloid lung disease.

miRNA profiling of primary lung and head and neck squamous cell carcinomas: Addressing a diagnostic dilemma.

OBJECTIVE: To determine whether microRNA (miRNA) profiling of primary lung and head and neck squamous cell carcinomas could be useful to identify a specific miRNA signature that can be used to further discriminate between primary lung squamous carcinomas and metastatic lesions in patients with a history of head and neck squamous cell cancer. METHODS: Specimens of resected primary head and neck and lung squamous cell carcinomas were obtained from formalin-fixed, paraffin-embedded blocks. Paraffin blocks were sectioned and deparaffinized, and total RNA was isolated and profiled. Quantitative polymerase chain reaction was performed to verify array results. RESULTS: Twelve head and neck and 16 lung squamous cell carcinoma samples met quality control metrics and were included for analysis. Forty-eight miRNAs were differentially expressed (P < .05) between the 2 groups. Of these, 30 were also significantly associated (q < .25) with tumor type in 2 independent sets of primary head and neck and lung squamous carcinomas profiled by The Cancer Genome Atlas consortium, including miR-34a and miR-10a. The ratio of miR-10a and miR-10b was especially predictive of primary cancer site in all 3 data sets, with area under the (receiver operating characteristics) curve values ranging from 0.922 to 0.982. Quantitative polymerase chain reaction confirmed the association of miR-34a expression and the miR-10:miR-10b ratio with tumor type. CONCLUSIONS: MicroRNA expression may be useful for discriminating between head and neck and lung squamous cell carcinomas, including miR-34a and the miR-10a:miR-10b ratio. This differentiation has clinical importance because it could help determine the appropriate therapeutic approach.

Extranodal Marginal Zone Endobronchial Lymphoma Associated With Hepatitis C.

We describe two patients with hepatitis C and a diagnosis of pulmonary extranodal marginal zone B cell lymphoma. Both patients demonstrated a chronic nonproductive cough without hemoptysis. Diagnosis was obtained after a computed tomographic chest scan and flexible bronchoscopic biopsy. We discuss the staging and prognosis of this disease, its correlation with hepatitis C, and potential benefits of treating the associated hepatitis C.

Surgical Management of Pulmonary Mucosa-Associated Lymphoid Tissue Lymphoma Associated With Light-Chain Deposition Disease.

A 52-year-old woman presented with a right middle lobe (RML) lung nodule suspicious for malignancy. Thoracoscopic middle lobectomy was performed. The pathology report revealed a pulmonary mucosa-associated lymphoid tissue (MALT) lymphoma in association with light-chain deposition disease (LCDD). Pulmonary MALT lymphoma and LCDD are unusual disorders presenting in the lung, and the association between these 2 conditions is even more uncommon. The optimal management for these patients is controversial, although surgical resection of localized well-circumscribed lesions may represent an effective therapeutic approach.

Quantitative serum free light chain assay in the diagnostic evaluation of AL amyloidosis.

We compared a new serum immunoassay for quantitation of serum free light chains (FLC) with the conventional tests for clonal immunoglobulin production: bone marrow immunohistochemistry, serum immunofixation electrophoresis, and urine immunofixation electrophoresis. Serum samples from 169 patients with AL amyloidosis and 20 controls were examined. Elevated levels of kappa-FLC and lambda-FLC were found in 94% and 93% of patients with the respective clonal disease. However, false positive elevations of kappa-FLC and lambda-FLC were found in 30% and 44% of patients with clonal disease of the other light chain subtype. We found that the FLC level was a reliable test for the diagnosis of clonal disease when the FLC kappa:lambda ratio was abnormal and was comparable to the conventional tests in patients with AL amyloidosis. After a histologic tissue diagnosis of amyloidosis, determining the type as AL amyloidosis relies on a panel of hematologic tests to determine light chain clonality and the exclusion other forms of amyloidosis.

High-dose melphalan and autologous stem-cell transplantation in patients with AL amyloidosis: an 8-year study.

BACKGROUND: AL amyloidosis is a fatal disease resulting from tissue deposition of amyloid fibrils derived from monoclonal immunoglobulin light chains. Treatment with oral chemotherapy is minimally effective. OBJECTIVE: To test survival and organ response in a large sample of patients treated with high-dose intravenous melphalan (100 to 200 mg/m2) and autologous blood stem-cell transplantation. DESIGN: 8-year longitudinal analysis of clinical effectiveness. SETTING: University-affiliated specialty referral clinic. PATIENTS: 701 consecutive new patients with AL amyloidosis. INTERVENTION: High-dose chemotherapy and autologous stem-cell transplantation for patients who met eligibility requirements based on organ involvement and clinical status. MEASUREMENTS: Survival analysis of all patients evaluated and a detailed analysis of treatment outcome in the subgroup that received high-dose melphalan and stem-cell transplantation. RESULTS: Among 701 patients with AL amyloidosis, 394 (56%) were eligible for high-dose melphalan and stem-cell transplantation; 82 did not proceed with treatment because of patient choice or disease progression. Median survival of the 312 patients who initiated treatment was 4.6 years. A complete hematologic response, defined as no evidence of an underlying plasma cell dyscrasia 1 year after treatment, was achieved in 40% of patients and was associated with prolonged survival. Statistically significant improvements occurred in end-organ disease and were greater in patients with a complete hematologic response. Mortality rate within 100 days of treatment with high-dose melphalan and stem-cell transplantation was 13%; patients with cardiomyopathy had the highest mortality rates. CONCLUSIONS: Treatment of selected patients with AL amyloidosis by using high-dose melphalan and stem-cell transplantation resulted in hematologic remission, improved 5-year survival, and reversal of amyloid-related disease in a substantial proportion.

Vertebral compression fractures as the initial presentation of AL amyloidosis: case series and review of literature.

The clinical presentation of AL amyloidosis is highly variable. In this series, we describe five cases of AL amyloidosis with vertebral compression fractures as initial presentation. All five patients had evidence of bone marrow replacement on magnetic resonance imaging and bone marrow biopsies demonstrating diffuse interstitial amyloid deposition. Hepatomegaly and elevated liver enzymes, consistent with liver involvement with amyloidosis, were also seen in each case. All five patients responded well to anti-plasma cell chemotherapy, with normalization of serum free light chain levels, reduction in alkaline phosphatase and improvement in pain and functional status. Although rare, AL amyloidosis should be considered in the differential diagnosis of selected patients with spontaneous vertebral compression fractures. Moreover, there seems to be an association of vertebral compression fractures with liver involvement in AL amyloidosis.

Bone marrow core biopsy specimens in AL (primary) amyloidosis. A morphologic and immunohistochemical study of 100 cases.

We retrospectively reviewed 100 bone marrow core biopsy specimens from patients with AL (primary) amyloidosis. The morphologic and immunohistochemical features were assessed by standard histochemical stains (H&E, periodic acid-Schiff, Congo red) and immunohistochemical stains for light chain immunoglobulins. Bone marrow core biopsy revealed a plasma cell dyscrasia in 83% (lambda, 65; kappa, 18) of cases. Amyloid deposits were observed in 60% of the bone marrow core biopsy specimens and, when present, were detected most often in blood vessel walls only (39/60). However, if present, interstitial amyloid deposition was significantly more associated with patients with a monoclonal kappa light chain gammopathy (P = .04). Through the careful analysis of standard histochemical and immunohistochemical stains, bone marrow core biopsy provides essential diagnostic information in cases of AL amyloidosis.