RUNX2/miR­31/SATB2 pathway in nickel­induced BEAS­2B cell transformation.

Nickel (Ni) compounds are classified as Group 1 carcinogens by the International Agency for Research on Cancer (IARC) and are known to be carcinogenic to the lungs. In our previous study, special AT­rich sequence­binding protein 2 (SATB2) was required for Ni­induced BEAS­2B cell transformation. In the present study, a pathway that regulates the expression of SATB2 protein was investigated in Ni­transformed BEAS­2B cells using western blotting and RT­qPCR for expression, and soft agar, migration and invasion assays for cell transformation. Runt­related transcription factor 2 (RUNX2), a master regulator of osteogenesis and an oncogene, was identified as an upstream regulator for SATB2. Ni induced RUNX2 expression and initiated BEAS­2B transformation and metastatic potential. Previously, miRNA­31 was identified as a negative regulator of SATB2 during arsenic­induced cell transformation, and in the present study it was identified as a downstream target of RUNX2 during carcinogenesis. miR­31 expression was reduced in Ni­transformed BEAS­2B cells, which was required to maintain cancer hallmarks. The expression level of miR­31 was suppressed by RUNX2 in BEAS­2B cells, and this increased the expression level of SATB2, initiating cell transformation. Ni caused the repression of miR­31 by placing repressive marks at its promoter, which in turn increased the expression level of SATB2, leading to cell transformation.

Glucocorticoid Receptor Antagonism Upregulates Somatostatin Receptor Subtype 2 Expression in ACTH-Producing Neuroendocrine Tumors: New Insight Based on the Selective Glucocorticoid Receptor Modulator Relacorilant.

Somatostatin exhibits an inhibitory effect on pituitary hormone secretion, including inhibition of growth hormone and adrenocorticotropic hormone (ACTH), and it can have antisecretory and antitumor effects on neuroendocrine tumors (NETs) that express somatostatin receptors. Although the precise mechanism remains unclear, the finding that glucocorticoids downregulate somatostatin receptor subtype 2 (SSTR2) expression has been used to explain the lack of efficacy of traditional SSTR2-targeting analogs in patients with ACTH-secreting NETs. Glucocorticoid receptor (GR) antagonism with mifepristone has been shown to reverse the glucocorticoid-induced downregulation of SSTR2; however, the effects of GR modulation on SSTR2 expression in ACTH-secreting NETs, particularly corticotroph pituitary tumors, are not well known. The current study presents new insight from in vitro data using the highly selective GR modulator relacorilant, showing that GR modulation can overcome dexamethasone-induced suppression of SSTR2 in the murine At-T20 cell line. Additional data presented from clinical case observations in patients with ACTH-secreting NETs suggest that upregulation of SSTR2 via GR modulation may re-sensitize tumors to endogenous somatostatin and/or somatostatin analogs. Clinical, laboratory, and imaging findings from 4 patients [2 ACTH-secreting bronchial tumors and 2 ACTH-secreting pituitary tumors (Cushing disease)] who were treated with relacorilant as part of two clinical studies (NCT02804750 and NCT02762981) are described. In the patients with ectopic ACTH secretion, SSTR2-based imaging (Octreoscan and 68Ga-DOTATATE positron emission tomography) performed before and after treatment with relacorilant showed increased radiotracer uptake by the tumor following treatment with relacorilant without change in tumor size at computed tomography. In the patients with Cushing disease who received relacorilant prior to scheduled pituitary surgery, magnetic resonance imaging after a 3-month course of relacorilant showed a reduction in tumor size. Based on these findings, we propose that GR modulation in patients with ACTH-secreting NETs upregulates previously suppressed SSTR2s, resulting in tumor-specific antisecretory and anti-proliferative effects. The effect of relacorilant on pituitary corticotroph tumors is being investigated in an ongoing phase 3 study (NCT03697109; EudraCT 2018-003096-35).

Clinical and biological features of B-cell neoplasms with CDK6 translocations: an association with a subgroup of splenic marginal zone lymphomas displaying frequent CD5 expression, prolymphocytic cells, and TP53 abnormalities.

A translocation involving the cyclin-dependent kinase 6 (CDK6) gene [t(CDK6)] is a rare but recurrent abnormality in B-cell neoplasms. To further characterise this aberration, we studied 57 cases; the largest series reported to date. Fluorescence in situ hybridisation analysis confirmed the involvement of CDK6 in all cases, including t(2;7)(p11;q21) immunoglobulin kappa locus (IGK)/CDK6 (n = 51), t(7;14)(q21;q32) CDK6/immunoglobulin heavy locus (IGH) (n = 2) and the previously undescribed t(7;14)(q21;q11) CDK6/T-cell receptor alpha locus (TRA)/T-cell receptor delta locus (TRD) (n = 4). In total, 10 patients were diagnosed with chronic lymphocytic leukaemia, monoclonal B-cell lymphocytosis or small lymphocytic lymphoma, and 47 had small B-cell lymphoma (SmBL) including 36 cases of marginal zone lymphoma (MZL; 34 splenic MZLs, one nodal MZL and one bronchus-associated lymphoid tissue lymphoma). In all, 18 of the 26 cytologically reviewed cases of MZL (69%) had an atypical aspect with prolymphocytic cells. Among the 47 patients with MZL/SmBL, CD5 expression was found in 26 (55%) and the tumour protein p53 (TP53) deletion in 22 (47%). The TP53 gene was mutated in 10/30 (33%); the 7q deletion was detected in only one case, and no Notch receptor 2 (NOTCH2) mutations were found. Immunoglobulin heavy-chain variable-region (IGHV) locus sequencing revealed that none harboured an IGHV1-02*04 gene. Overall survival was 82% at 10 years and not influenced by TP53 aberration. Our present findings suggest that most t(CDK6)+ neoplasms correspond to a particular subgroup of indolent marginal zone B-cell lymphomas with distinctive features.

Role of Napsin A and Survivin Immunohistochemical Expression in Bronchogenic Adenocarcinoma.

BACKGROUND: Lung cancer, being the leading cause of cancer deaths with most patients diagnosed at a late stage, represents a major burden in developing countries especially with both air pollution and tobacco use increasing. With the evolution of new, successful therapies that target lung adenocarcinoma, it became of utmost importance to diagnose lung adenocarcinoma. Despite considering TTF-1 as the predominant marker for identifying lung adenocarcinoma but it has limited sensitivity and specificity, which means that its expression decreases in relation to the degree of tumor differentiation. AIM OF WORK: this study intended to evaluate the use of Napsin A in lung adenocarcinoma, and observe if it can withstand along the different lines of tumor differentiation and Survivin as a marker of poor prognosis. MATERIALS AND METHODS: Forty paraffin blocks of bronchogenic carcinoma were collected and studied immunohistochemically against Napsin A and Survivin. RESULTS: There was a statistically significant relation between Napsin A reactivity and tumor grade as 72% of grade II as well as all cases of grade I were strongly positive compared to none of grade III cases. Another statistically significant relation between Survivin reactivity and tumor grade was observed as all grades I and II cases showed labeling index <10%, while all grade III cases showed labeling index >10%. CONCLUSION: Napsin A is a good prognostic marker while Survivin stands as a poor one for lung adenocarcinoma with a statistically inverse relation between the two, which means that Napsin A can't be used as a marker for diagnosing poorly differentiated tumors.
.

Human bronchial carcinoid tumor initiating cells are targeted by the combination of acetazolamide and sulforaphane.

BACKGROUND: Bronchial carcinoids are neuroendocrine tumors that present as typical (TC) and atypical (AC) variants, the latter being more aggressive, invasive and metastatic. Studies of tumor initiating cell (TIC) biology in bronchial carcinoids has been hindered by the lack of appropriate in-vitro and xenograft models representing the bronchial carcinoid phenotype and behavior. METHODS: Bronchial carcinoid cell lines (H727, TC and H720, AC) were cultured in serum-free growth factor supplemented medium to form 3D spheroids and serially passaged up to the 3rd generation permitting expansion of the TIC population as verified by expression of stemness markers, clonogenicity in-vitro and tumorigenicity in both subcutaneous and orthotopic (lung) models. Acetazolamide (AZ), sulforaphane (SFN) and the AZ + SFN combination were evaluated for targeting TIC in bronchial carcinoids. RESULTS: Data demonstrate that bronchial carcinoid cell line 3rd generation spheroid cells show increased drug resistance, clonogenicity, and tumorigenic potential compared with the parental cells, suggesting selection and expansion of a TIC fraction. Gene expression and immunolabeling studies demonstrated that the TIC expressed stemness factors Oct-4, Sox-2 and Nanog. In a lung orthotopic model bronchial carcinoid, cell line derived spheroids, and patient tumor derived 3rd generation spheroids when supported by a stroma, showed robust tumor formation. SFN and especially the AZ + SFN combination were effective in inhibiting tumor cell growth, spheroid formation and in reducing tumor formation in immunocompromised mice. CONCLUSIONS: Human bronchial carcinoid tumor cells serially passaged as spheroids contain a higher fraction of TIC exhibiting a stemness phenotype. This TIC population can be effectively targeted by the combination of AZ + SFN. Our work portends clinical relevance and supports the therapeutic use of the novel AZ+ SFN combination that may target the TIC population of bronchial carcinoids.

Challenges in diagnosis of disease reported 100 years back: Cushing syndrome; recent advances.

Treatment of Cushing syndrome depends on diagnosis of etiology responsible for hypercortisolism in the body, which sometimes presents with a challenge. Inferior petrosal sinus sampling for ACTH levels, followed by peripheral venous sampling is a proven tool to be a gold standard for differentiating between peripheral and central cause of ACTH dependent Cushing syndrome. This case report is of an elderly female who presented as an outpatient in the endocrinology clinic of Aga Khan university hospital on 22/6/2017 with clinical features of hypercortisolism. After workup she was found to have cushing syndrome secondary to ACTH secreting bronchial carcinoid tumour.

Pediatric Bronchial Carcinoid Tumors: A Case Series and Review of the Literature.

Bronchial carcinoid tumor, while rare, remains the most common primary malignant lung tumor in children. We present a retrospective analysis of 7 patients with typical bronchial carcinoid tumors diagnosed at 2 pediatric tertiary care referral centers between 1990 and 2014. The most common presenting symptom was pneumonia, followed by respiratory distress. Somatostatin scans were performed in selected patients. All patients had negative resection margin following surgery and were alive without disease at last follow-up. Typical carcinoid tumors have a good prognosis following definitive surgical resection. A review of published literature on pediatric bronchial carcinoid tumors is provided.

Salvage peptide receptor radionuclide therapy with [177Lu-DOTA,Tyr3]octreotate in patients with bronchial and gastroenteropancreatic neuroendocrine tumours.

PURPOSE: Therapy with [177Lu-DOTA,Tyr3]octreotate is effective in patients with grade I/II metastasized and/or inoperable bronchial neuroendocrine tumour (NET) or gastroenteropancreatic NET (GEP-NET). In this study, we investigated the efficacy and safety of salvage treatment with [177Lu-DOTA,Tyr3]octreotate. METHODS: Patients with progressive bronchial NET or GEP-NET were selected for re-(re)treatment if they had benefited from initial peptide receptor radionuclide therapy (I-PRRT) with a minimal progression-free survival (PFS) of 18 months. Patients received an additional cumulative dose of 14.8 GBq of [177Lu-DOTA,Tyr3]octreotate over two cycles per retreatment with PRRT (R-PRRT) or re-retreatment with PRRT (RR-PRRT). RESULTS: The safety and efficacy analyses included 181 patients and 168 patients, respectively, with bronchial NET or GEP-NET. Overall median follow-up was 88.6 months (95% CI 79.0-98.2). Median cumulative doses were 44.7 GBq (range 26.3-46.4 GBq) during R-PRRT (168 patients) and 59.7 GBq (range 55.2-≤60.5 GBq) during RR-PRRT (13 patients). Objective response and stable disease, as best response, were observed in 26 patients (15.5%) and 100 patients (59.5%) following R-PRRT, and in 5 patients (38.5%) and 7 patients (53.8%) following RR-PRRT, respectively. Median PFS was 14.6 months (95% CI 12.4-16.9) following R-PRRT and 14.2 months (95% CI 9.8-18.5) following RR-PRRT. Combined overall survival (OS) after I-PRRT plus R-PRRT and RR-PRRT was 80.8 months (95% CI 66.0-95.6). Grade III/IV bone marrow toxicity occurred in 6.6% and 7.7% of patients after R-PRRT and RR-PRRT, respectively. Salvage therapy resulted in a significantly longer OS in patients with bronchial NET, GEP-NET and midgut NET than in a nonrandomized control group. The total incidence of acute myeloid leukaemia (AML) and myelodysplastic syndrome (MDS) was 2.2%. No PRRT-related grade III/IV nephrotoxicity was observed. CONCLUSION: A cumulative dose of up to 60.5 GBq salvage PRRT with [177Lu-DOTA,Tyr3]octreotate is safe and effective in patients with progressive disease (relapse-PD) following I-PRRT with [177Lu-DOTA,Tyr3]octreotate. Safety appears similar to that of I-PRRT as no higher incidence of AML or MDS was observed. No grade III/IV renal toxicity occurred after retreatment.

Hyalinizing clear cell carcinoma of the bronchial glands: presentation of three cases and pathological comparisons with salivary gland counterparts and bronchial mucoepidermoid carcinomas.

Hyalinizing clear cell carcinoma of the bronchial glands is a very rare tumor. Since only five reports describing six tumors have been published to date, only a little is known about specific histologic findings and clinical features. Because of its rarity, hyalinizing clear cell carcinoma has not been described in the latest WHO classification of pulmonary tumors yet. Here we present three cases of bronchial hyalinizing clear cell carcinomas, confirmed by both fluorescence in situ hybridization (FISH) and RT-PCR, focusing on histologic and immunohistochemical characteristics in a comparison with three cases of salivary gland origin. In addition, we compared immunohistochemical features with bronchial mucoepidermoid carcinoma, a lesion that needs to be taken into account in differential diagnosis of hyalinizing clear cell carcinoma. All our bronchial hyalinizing clear cell carcinoma cases were surgically resected. Histologically, tumor cells showed clear to eosinophilic cytoplasm with hyalinizing stroma in various proportions, resembling those of salivary gland origin. Immunohistochemically, tumor cells were positive for CK7, CK5/6, p40, p63, and ATF1, while they were negative for TTF1, Napsin A, HMB45, and SOX10. The CK5/6 staining pattern varied in mucoepidermoid carcinomas, while that of hyalinizing clear cell carcinoma was uniformly positive. FISH revealed EWSR1-ATF1 fusion, and RT-PCR with sequencing confirmed specificity of the chimeric gene for hyalinizing clear cell carcinoma. Clinically, bronchial hyalinizing clear cell carcinoma was characterized by occurrence in the fourth to sixth decades, no link with smoking history, and a predilection for the right lung, in line with previous reports. In summary, our study confirmed that the bronchial hyalinizing clear cell carcinoma is a histologically and genetically identical tumor to that of salivary gland origin, and that gene rearrangement analysis can play a critical role in distinction from mucoepidermoid carcinoma.

The Prognostic Significance of Notch1 and Fatty Acid Binding Protein 7 (FABP7) Expression in Resected Tracheobronchial Adenoid Cystic Carcinoma: A Multicenter Retrospective Study.

PURPOSE: Adenoid cystic carcinoma (ACC) of the trachea and bronchus is a rare tumor. Although MYB-NFIB oncogene fusion and Notch1 mutation have been identified in ACC, little is known about the expression and clinical significance of Notch1 and its target gene fatty acid binding protein 7 (FABP7) in tracheobronchial ACC. MATERIALS AND METHODS: Primary tracheobronchial ACC that were resected between 1998 and 2014 were identified through the pathology and oncology database from five thoracic oncology centers in China. A tissue array was constructed from the patients' samples and the expressions of Notch1 and FABP7 were evaluated by immunohistochemistry. The association between the expression of both markers and survival was determined. RESULTS: Overexpression of Notch1 and FABP7, detected in 37.8% and 38.3% of 368 patients with tracheobronchial ACC, respectively, was an independent prognostic indicator for recurrencefree survival (RFS) by multivariable Cox proportional hazard model (p=0.032 and p=0.048, respectively). Overexpression of Notch1, but not of FABP7, predicted overall survival (OS) (p=0.018). When categorized into four groups according to coexpression of Notch1 and FABP7, patients with overexpression of both Notch1 and FABP7 belonged to the group with the shortest RFS and OS (p=0.01 and p=0.048, respectively). CONCLUSION: Expression of Notch1 and FABP7, and coexpression of Notch1 and FABP7, is strongly associated with poor survival in resected tracheobronchial ACC. These data are consistent with the hypothesis that poor differentiation of tracheobronchial ACC correlates with the activation of Notch signaling.

Fabrication and characterization of gefitinib-releasing polyurethane foam as a coating for drug-eluting stent in the treatment of bronchotracheal cancer.

The purpose of the present study was to develop gefitinib-loaded polymeric foams that can be used as coating of drug-eluting stents for palliative treatment of bronchotracheal cancer. Release of such an anticancer drug from such stent coating can retard tumor regrowth into the bronchial lumen. Gefitinib-loaded polyurethane (PU) foams were prepared by embedding either gefitinib micronized crystals or gefitinib-loaded poly(lactic-co-glycolic acid) microspheres in water-blown films, with up to 10% w/w loading for gefitinib microcrystals and 15% w/w for gefitinib microspheres (corresponding to 1.0% w/w drug loading). Drug-release studies showed sustained release of gefitinib over a period of nine months, with higher absolute release rates at higher drug loading content. By the end of the studied nine month release periods, 60-100% of the loaded gefitinib had been released. Foams loaded with gefitinib-PLGA microspheres at 15% w/w showed accelerated drug release after 4 months, coinciding with the degradation of PLGA microparticles in the PU foam as demonstrated by scanning electron microscopy (SEM). When applied on a nitinol braided bronchotrachial stent, PU coatings with gefitinib microspheres showed similar mechanical properties as the drug-free PU coating, which indicated that the loading of microspheres did not affect the mechnical properties of the PU foams. In conclusion, we have fabricated drug-loaded PU foams that are suitable for bronchotracheal stent coating.

[Report of Successful Treatment of A Rectal Cancer Patient with Endobronchial 
Metastasis by Bronchial Stent Implantation Combined with Chemotherapy and Apatinib].

The lungs are the most common sites of metastases from non-pulmonary malignancies. On the other hand, endobronchial metastases are rare. Various tumors have been associated with endobronchial metastasis, most commonly renal, breast and colorectal cancer. Advanced rectal cancerwith lung metastasis is common. However, endobronchial metastasis without lung metastasis of rectal cancer is rare, and easily misdiagnosed. We report one case of postoperative rectal cancer with endobronchial, pleuralcavity, pericardial cavitymetastasis, giving the comprehensive treatment of bronchial stentimplantation, chemotherapy, targeted drugs and remission. The process of diagnosis and treatmentis relatively complex, therefore it has a certain clinical reference value.

ECTOPIC CUSHING SYNDROME: A 10-YEAR EXPERIENCE FROM A TERTIARY CARE CENTER IN SOUTHERN INDIA.

OBJECTIVE: Ectopic adrenocorticotropic hormone (ACTH) secretion is a less common cause of Cushing syndrome and is seen in 5 to 10% of cases with endogenous hypercortisolemia. We hereby describe our experience of patients with ectopic ACTH syndrome, who have been managed over the past 10 years at a tertiary care center in Southern India. METHODS: The inpatient and outpatient records of patients from 2006 to 2015 were retrospectively reviewed. The clinical features, clinical history, biochemical values, imaging features, including radiologic findings and positron emission tomography scans, management, details of follow-up, and outcomes, were documented. We compared the biochemical findings in these patients with 20 consecutive patients with Cushing disease (Cushing syndrome of pituitary origin). RESULTS: A total of 21 patients were studied. The median age at presentation was 34 years (range, 19 to 55 years). Seven patients had thymic carcinoid, 7 had bronchial carcinoid, 3 had lung malignancies, 2 had medullary carcinoma thyroid, 1 patient had a pancreatic neuroendocrine tumor, and 1 patient had an occult source of ACTH. The most common clinical features at presentation were muscle weakness (95%), hyperpigmentation (90%), facial puffiness (76%), easy bruising (61%), edema (57%), and striae (52%). Extensive acne was seen in a large number of patients (43%). Only 3 patients (14%) had central obesity. The median 8 am cortisol was 55.5 µg/dL (range, 3.8 to 131 µg/dL), median 8 am ACTH was 207 pg/mL (range, 31.1 to 703 pg/mL), and the median 24-hour urinary free cortisol was 2,484 µg (range, 248 to 25,438 µg). Basal cortisol and ACTH, as well as midnight cortisol and ACTH level, were markedly higher in patients with ectopic Cushing syndrome as compared to patients with Cushing disease. Twelve of 21 patients had developed life-threatening infections by follow-up. Nine patients had undergone surgical intervention to address the primary tumor. However, only 1 patient exhibited a complete cure on follow-up. CONCLUSION: In our series, ectopic Cushing syndrome was most commonly seen in association with intrathoracic tumors such as bronchial or thymic carcinoid. Hyperpigmentation and proximal myopathy were frequent, while central obesity was uncommon. Early and rapid control of hypercortisolemia was important in order to prevent life-threatening infections and metabolic complications. ABBREVIATIONS: ACTH = adrenocorticotropic hormone CT = computed tomography DOTATATE = 68Ga-DOTA-Tyr3-octreotate ECS = ectopic Cushing syndrome FDG = fluorodeoxyglucose MTC = medullary thyroid cancer NET = neuroendocrine tumor PET = positron emission tomography.

Observation of Zn-photoprotoporphyrin red Autofluorescence in human bronchial cancer using color-fluorescence endoscopy.

BACKGROUND: We observed red autofluorescence emanating from bronchial cancer lesions using a sensitive color-fluorescence endoscopy system. We investigated to clarify the origin of the red autofluorescence. METHODS: The wavelengths of the red autofluorescence emanating from lesions were measured in eight patients using a spectrum analyzer and compared based on pathologic findings. Red autofluorescence at 617.3, 617.4, 619.0, and 617.1 nm was emitted by normal bronchus, inflamed tissue, tissue exhibiting mild dysplasia, and malignant lesions, respectively. Protoporphyrin, uroporphyrin, and coproporphyrin, the major porphyrin derivatives in human blood, were purchased to determine which porphyrin derivative is the source of red fluorescence when acquired de novo. We synthesized photoporphyrin, Zn-protoporphyrin and Zn-photoprotoporphyrin from protoporphyrin. RESULTS: Coproporphyrin and uroporphyrin emitted only weak fluorescence. Fluorescence was emitted by our synthesized Zn-photoprotoporphyrin at 625.5 nm and by photoprotoporphyrin at 664.0 nm. CONCLUSIONS: From these results, we conclude that Zn-photoprotoporphyrin was the source of the red autofluorescence observed in bronchial lesions. Zn-protoporphyrin is converted to Zn-photoprotoporphyrin by radiation with excitation light. Our results suggest that red autofluorescence emanating from Zn-photoprotoporphyrin in human tissues could interfere with photodynamic diagnosis using porphyrin derivatives such as Photofrin® and Lazerphyrin® with a sensitive endoscopy system, because color cameras cannot differentiate Zn-photoprotoporphyrin red fluorescence from that of other porphyrin derivatives.

Endobronchial plasmacytoma in patient with multiple myeloma.

Endobronchial plasmacytoma is a rare manifestation of extramedullary plasmacytoma. A 49-year-old woman with a history of multiple myeloma consulted to our pulmonary service with progressive dyspnoea and cough and abnormal chest X-ray. A lesion measuring 6 × 5 cm in size existed in anterior baseline of the right lung's lower lobe in thoracic computed tomography in addition to right bronchial narrowing and atelectasis distal in lesions. Diagnostic bronchoscopy was performed previously for the obstruction and biopsy was taken from the lesion in the right middle lobe bronchus. Endobronchial biopsies showed extensive tumour infiltration with plasmocytoid cells. Immunohistochemistry was positive CD138 and Lamda. Microscopic and immunohistochemical findings supported the diagnosis of extramedullary endobronchial plasmacytoma.

Oncogenic transformation of human lung bronchial epithelial cells induced by arsenic involves ROS-dependent activation of STAT3-miR-21-PDCD4 mechanism.

Arsenic is a well-documented human carcinogen. The present study explored the role of the onco-miR, miR-21 and its target protein, programmed cell death 4 (PDCD4) in arsenic induced malignant cell transformation and tumorigenesis. Our results showed that treatment of human bronchial epithelial (BEAS-2B) cells with arsenic induces ROS through p47phox, one of the NOX subunits that is the key source of arsenic-induced ROS. Arsenic exposure induced an upregulation of miR-21 expression associated with inhibition of PDCD4, and caused malignant cell transformation and tumorigenesis of BEAS-2B cells. Indispensably, STAT3 transcriptional activation by IL-6 is crucial for the arsenic induced miR-21 increase. Upregulated miR-21 levels and suppressed PDCD4 expression was also observed in xenograft tumors generated with chronic arsenic exposed BEAS-2B cells. Stable shut down of miR-21, p47phox or STAT3 and overexpression of PDCD4 or catalase in BEAS-2B cells markedly inhibited the arsenic induced malignant transformation and tumorigenesis. Similarly, silencing of miR-21 or STAT3 and forced expression of PDCD4 in arsenic transformed cells (AsT) also inhibited cell proliferation and tumorigenesis. Furthermore, arsenic suppressed the downstream protein E-cadherin expression and induced ß-catenin/TCF-dependent transcription of uPAR and c-Myc. These results indicate that the ROS-STAT3-miR-21-PDCD4 signaling axis plays an important role in arsenic -induced carcinogenesis.

TNFα-induced airway smooth muscle cell proliferation depends on endothelin receptor signaling, GM-CSF and IL-6.

UNLABELLED: Pathological proliferation of human airway smooth muscle cells (HASMCs) causes hyperplasia in chronic lung diseases. Signaling pathways that link airway inflammation to HASMC proliferation might provide therapeutic targets for the prevention of airway remodeling and chronic lung diseases. Endothelin-1 (ET-1) signals via endothelin-A- and B-receptors (ETAR, ETBR) to perpetuate HASMC-associated and TNFα-dependent inflammatory processes. HYPOTHESIS: endothelin receptor antagonists (ERAs) suppress HASMC proliferation induced by inflammatory cytokines. HASMCs were stimulated ex vivo with cytokines in the presence or absence of ERAs (ETAR-specific/selective: BQ123, ambrisentan; ETBR-specific: BQ788; non-selective: bosentan, macitentan, ACT-132577) or cytokine-blocking antibodies. Cell counts, DNA-synthesis (BrdU-incorporation assay), cytokine production (ELISA) and ETBR expression (whole-genome microarray data, western blot) were analyzed. ET-1-induced HASMC proliferation and DNA-synthesis were reduced by protein kinase inhibitors and ETAR-specific/selective ERAs but not by BQ788. TNFα-induced HASMC proliferation and DNA-synthesis were reduced by all ERAs. TNFα induced ET-1 and ETBR expression. TNFα- and ET-1-induced GM-CSF releases were both reduced by BQ123 and BQ788. TNFα- and ET-1-induced IL-6 releases were both reduced by BQ123 but not by BQ788. Combined but not single blockade of GM-CSF-receptor-α-chain and IL-6 reduced TNFα- and ET-1-induced HASMC proliferation and DNA-synthesis. Combined but not single treatment with GM-CSF and IL-6 induced HASMC proliferation and DNA-synthesis in the presence of ET-1. In conclusion, TNFα induces HASMC proliferation via ET-1/GM-CSF/IL-6. ETBR requires up-regulation by TNFα to mediate ET-1 effects on HASMC proliferation. This signaling cascade links airway inflammation to HASMC-associated remodeling processes and is sensitive to ERAs. Therefore, ERAs could prevent inflammation-induced airway smooth muscle hyperplasia.

Peptide receptor radionuclide therapy: focus on bronchial neuroendocrine tumors.

Well-differentiated bronchial neuroendocrine tumors (B-NETs) are rare. They represent 1-5 % of all lung cancers. The incidence of these neoplasms has risen over the past 30 years and, especially for advanced or metastatic disease, management is complex and requires a multidisciplinary approach. Treatment with somatostatin analogs (SSAs) is the most important first-line therapy, in particular in well-differentiated NETs with high somatostatin type receptor (SSTR) expression. In these tumors, the role of mammalian target of rapamycin (m-TOR) inhibitors and the potential utility of other target therapies remain unclear while chemotherapy represents the gold standard treatment only for aggressive forms with low SSTR expression. Peptide receptor radionuclide therapy (PRRT) is an emerging treatment modality for advanced NETs. There are many cumulative evidences about the effectiveness and tolerability of this therapeutic approach, especially in gastro-entero-pancreatic (GEP)-NETs. For B-NETs, scientific research is moving more slowly. Here, we performed a review in order to evaluate the efficacy and toxicity of PRRT with a focus on patients with inoperable or metastatic well-differentiated B-NETs.

Neuroendocrine tumors producing calcitonin: characteristics, prognosis and potential interest of calcitonin monitoring during follow-up.

OBJECTIVES: Inappropriate calcitonin (CT) release, a major feature of medullary thyroid cancer (MTC), may occur in neuroendocrine tumors (NETs). The aims of this retrospective study were to assess i) the characteristics and prognosis of CT-producing NETs, and ii) the value of CT monitoring during follow-up. METHODS: All patients with NETs in whom serum CT was assayed between 2010 and 2012 were included. MTCs were excluded. Clinical, biological, and histological characteristics were studied. RESULTS: Twenty-one (12%) of 176 patients in whom serum CT was systematically assayed had concentrations >100  ng/l, with tumours predominantly of bronchial or pancreatic origin (P<0.0001), and of high grade (P=0.0006). Poor prognosis was linked to high CT levels, poor differentiation, and grade 3. In a total group of 24 patients with serum CT >100  ng/l, symptoms potentially attributable to CT were recorded in eight, with occasional overlap with the carcinoid syndrome among other secretory syndromes. Immunohistochemistry could be performed in six tumor specimens, CT being detected in five. In 11 patients with five or more successive CT assays, hormone levels were fairly well correlated with clinical courses. CONCLUSION: Serum CT levels may be raised in some patients with NETs, especially from foregut origin, and of high grade. The suggested value of CT monitoring during follow-up must be confirmed in further studies.

Nuclear EGFR renders cells radio-resistant by binding mRNA species and triggering a metabolic switch to increase lactate production.

BACKGROUND AND PURPOSE: EGFR is translocated into the cell nucleus in response to irradiation, where it is involved in regulation of radio-sensitivity. The aim of this study is to elucidate the functional role of nuclear EGFR. MATERIAL AND METHODS: To identify EGFR-bound nuclear proteins and mRNAs, Maldi-TOF analysis and mRNA gene arrays were used. Complex formation of proteins was shown by confocal microscopy, immunoprecipitation and Western blotting. The effect of EGFR binding to mRNAs was exhibited by quantitative RT-PCR. Cellular endpoints were shown by Western blotting, mitochondrial mass quantification, lactate quantification and clonogenic survival assays. RESULTS: Maldi-TOF analysis of proteins bound to nuclear EGFR in response to irradiation showed colocalization with Lamin A and heterogeneous nuclear ribonucleoproteins. Confocal microscopy and Western blotting confirmed this colocalization. Both Lamin A and heterogeneous nuclear ribonucleoproteins are involved in mRNA processing. To support a role of nEGFR in this context after irradiation, we isolated EGFR-bound mRNA and observed an EGFR kinase-dependent mRNA stabilizing effect. With the help of DNA microarrays, we identified mRNAs associated with the Warburg effect that were bound to nuclear EGFR. In this context, we observed radiation-induced HIF1α expression, which triggers inhibition of pyruvate dehydrogenase and blocks the tricarboxylic acid cycle. Consequently, we detected mitophagy and increased lactate production, which is associated with increased treatment resistance. Reduction of nEGFR decreased radiation-induced expression of Hif1α and lactate production. CONCLUSIONS: We showed that nuclear EGFR selectively binds and stabilizes mRNA involved in the Warburg effect in response to irradiation. As a consequence, cells switch from aerobic to anaerobic glucose metabolism, which can be prevented by HIF1α inhibitor BAY87-2243, Dasatinib, Erlotinib or EGFR siRNA.