Goetz H. Kloecker

Exosomal microRNA: A Diagnostic Marker for Lung Cancer

PURPOSE To date, there is no screening test for lung cancer shown to affect overall mortality. MicroRNAs (miRNAs) are a class of small noncoding RNA genes found to be abnormally expressed in several types of cancer, suggesting a role in the pathogenesis of human cancer. PATIENTS AND METHODS We evaluated the circulating levels of tumor exosomes, exosomal small RNA, and specific exosomal miRNAs in patients with and without lung adenocarcinoma, correlating the levels with the American Joint Committee on Cancer (AJCC) disease stage to validate it as an acceptable marker for diagnosis and prognosis in patients with adenocarcinoma of the lung. RESULTS To date, 27 patients with lung adenocarcinoma AJCC stages I-IV and 9 controls, all aged 21-80 years, were enrolled in the study. Small RNA was detected in the circulating exosomes. The mean exosome concentration was 2.85 mg/mL (95% CI, 1.94-3.76) for the lung adenocarcinoma group versus 0.77 mg/mL (95% CI, 0.68-0.86) for the control group (P < .001). The mean miRNA concentration was 158.6 ng/mL (95% CI, 145.7-171.5) for the lung adenocarcinoma group versus 68.1 ng/mL (95% CI, 57.2-78.9) for the control group (P < .001). Comparisons between peripheral circulation miRNA-derived exosomes and miRNA-derived tumors indicated that the miRNA signatures were not significantly different. CONCLUSION The significant difference in total exosome and miRNA levels between lung cancer patients and controls, and the similarity between the circulating exosomal miRNA and the tumor-derived miRNA patterns, suggest that circulating exosomal miRNA might be useful as a screening test for lung adenocarcinoma. No correlation between the exosomal miRNA levels and the stage of disease can be made at this point.

Differential pathways regulating innate and adaptive antitumor immune responses by particulate and soluble yeast-derived β-glucans

β-glucans have been reported to function as a potent adjuvant to stimulate innate and adaptive immune responses. However, β-glucans from different sources are differential in their structure, conformation, and thus biologic activity. Different preparations of β-glucans, soluble versus particulate, further complicate their mechanism of action. Here we show that yeast-derived particulate β-glucan activated dendritic cells (DCs) and macrophages via a C-type lectin receptor dectin-1 pathway. Activated DCs by particulate β-glucan promoted Th1 and cytotoxic T-lymphocyte priming and differentiation in vitro. Treatment of orally administered yeast-derived particulate β-glucan elicited potent antitumor immune responses and drastically down-regulated immunosuppressive cells, leading to the delayed tumor progression. Deficiency of the dectin-1 receptor completely abrogated particulate β-glucan-mediated antitumor effects. In contrast, yeast-derived soluble β-glucan bound to DCs and macrophages independent of the dectin-1 receptor and did not activate DCs. Soluble β-glucan alone had no therapeutic effect but significantly augmented antitumor monoclonal antibody-mediated therapeutic efficacy via a complement activation pathway but independent of dectin-1 receptor. These findings reveal the importance of different preparations of β-glucans in the adjuvant therapy and allow for the rational design of immunotherapeutic protocols usable in clinical trials.

The Role of Human Papilloma Virus in Lung Cancer: A Review of the Evidence

Papillomaviruses are small nonenveloped DNA viruses that infect squamous epithelial cells. These viruses have been found in many organisms. Human papillomaviruses (HPVs) give rise to a large spectrum of epithelial lesions, mainly benign hyperplasia (eg, warts and papillomas) with low malignant potential. There is a subgroup of HPV, the “high-risk” HPV, which is associated with precancerous and cancerous lesions. A small fraction of people infected with high-risk HPV will develop cancers that usually arise many years after the initial infection (Psyrri and Dimaio, Nat Clin Pract Oncol. 2008;5:24–31). Nonsmall cell lung cancer is a heterogeneous disease. The most common histologic subtypes include squamous cell carcinoma, adenocarcinoma, and large cell carcinoma. Despite different histologies, nonsmall cell lung cancers are often classified together because of similarities in approach and management of the disease. In this article, we reviewed the current literature on lung cancer and HPV. On the basis of this data, we suggested a possible mechanism of carcinogenesis induced by HPV.

The Quality of Medical Evidence in Hematology-Oncology

PURPOSE The purpose of this study was to evaluate the quality of the medical evidence available to the clinician in the practice of hematology/oncology. METHODS We selected 14 neoplastic hematologic disorders and identified 154 clinically important patient management decision/interventions, ranging from initial treatment decisions to those made for the treatment of recurrent or refractory disease. We also performed a search of the scientific literature for the years 1966 through 1996 to identify all randomized controlled trials in hematology/oncology. RESULTS We identified 783 randomized controlled trials (level 1 evidence) pertaining to 37 (24%) of the decision/interventions. An additional 32 (21%) of the decision/interventions were supported by evidence from single arm prospective studies (level 2 evidence). However, only retrospective or anecdotal evidence (level 3 evidence) was available to support 55% of the identified decision/interventions. In a retrospective review of the decision/interventions made in the management of 255 consecutive patients, 78% of the initial decision/interventions in the management of newly diagnosed hematologic/oncologic disorders could have been based on level 1 evidence. However, more than half (52%) of all the decision/interventions made in the management of these 255 patients were supported only by level 2 or 3 evidence. CONCLUSIONS We conclude that level 1 evidence to support the development of practice guidelines is available primarily for initial decision/interventions of newly diagnosed diseases. Level 1 evidence to develop guidelines for the management of relapsed or refractory malignant diseases is currently lacking.

Pemetrexed with or without Matuzumab as Second-Line Treatment for Patients with Stage IIIB/IV Non-small Cell Lung Cancer

Introduction: This randomized phase II study investigated pemetrexed in combination with the epidermal growth factor receptor (EGFR)-targeting monoclonal antibody matuzumab compared with pemetrexed alone as second-line therapy for patients with advanced non-small cell lung cancer. Methods: Patients received pemetrexed 500 mg/m2 every 3 weeks either alone (n = 50) or in combination with matuzumab at either 800 mg weekly (n = 51) or 1600 mg every 3 weeks (n = 47). The primary end point was objective response, as assessed by an independent review committee. Results: Tumor EGFR expression was detected in 87% of randomized patients. The objective response rate for the pooled matuzumab-treated arms was 11% compared with 5% for pemetrexed alone (p = 0.332). Apart from one patient in the pemetrexed alone group, all responses occurred in patients whose tumors expressed EGFR. The objective response rate for patients receiving weekly matuzumab was 16% compared with 2% for those receiving matuzumab every 3 weeks. There was also a trend for improved overall survival in patients receiving matuzumab weekly versus every 3 weeks (12.4 months versus 5.9 months, respectively, versus 7.9 months for pemetrexed alone). The combination of pemetrexed and matuzumab demonstrated an acceptable safety profile, with the most common grade 3/4 adverse event being neutropenia. Conclusion: Although the analysis on the pooled matuzumab-treated arms did not demonstrate a statistically significant improvement in objective response for the addition of matuzumab to pemetrexed compared with pemetrexed alone, the trends for improvement in objective response and overall survival for pemetrexed plus weekly matuzumab compared with pemetrexed alone warrant confirmation in additional clinical trials.

Argatroban for anticoagulation during cardiac surgery.

Background: The aim of this study was to report our experience and review the published data on argatroban administration during adult cardiac surgery. Methods: The information on all reported cases of argatroban use in adults, during cardiac surgery was reviewed, including that of the patient described here. This analysis focused on patient characteristics, type of surgery, argatroban dosing schedule, monitoring of anticoagulation and outcomes. Results: Twenty‐one cases have been reported. Fifteen patients underwent off‐pump surgical procedures with the argatroban dose adjusted to maintain an activated clotting time (ACT) range between 200 and 300 s. Three intraoperative thrombi occurred in two patients when the ACT was <280 s. None had coagulopathy. Six cases reported the use of argatroban during on‐pump cardiac surgery dosed to keep the ACT >400 s. Intraoperative thrombotic complications were not reported in this group; however, one clot in the pump was noted after the procedure when the ACT was between 300 and 350 s. All six cases required larger volumes of perioperative blood products and three had severe coagulopathy. Of the 21 cases, seven had an indication for continued anticoagulation following surgery. Four cases did not report further use of argatroban after surgery. Three patients received argatroban after surgery without complications. Recommendations for how to use argatroban during cardiac surgery are proposed. Conclusions: Argatroban, with ACT monitoring, might be safely used for anticoagulation during cardiac surgery.

Hepatoid adenocarcinoma of the lung: report of five cases and review of the literature

The current diagnostic criteria for hepatoid adenocarcinoma of lung include typical acinar or papillary adenocarcinoma and a component resembling hepatocellular carcinoma and expressing α-fetoprotein (AFP). Distinguishing hepatoid adenocarcinoma of lung from hepatocellular carcinoma metastatic to lung is difficult in patients with both lung and liver masses and in patients at risk for lung and liver cancer because of smoking and viral hepatitis, respectively. We studied morphologic features of hepatoid adenocarcinoma of lung and established an immunohistochemical panel to facilitate distinction of hepatoid adenocarcinoma of lung from hepatocellular carcinoma metastatic to lung. Five cases of hepatoid adenocarcinoma of lung were stained with hematoxylin and eosin and mucicarmine for histomorphologic evaluation. The 14-marker immunohistochemical profile was established for hepatoid adenocarcinoma of lung and compared with that of hepatocellular carcinoma. Two cases of hepatoid adenocarcinoma of lung had signet-ring cell components. Three cases were pure hepatoid adenocarcinoma without components of acinar or papillary adenocarcinoma, signet-ring cells or neuroendocrine carcinoma. Like hepatocellular carcinoma, hepatoid adenocarcinoma of lung expresses CK8 (5/5), CK18 (5/5), AFP (3/5) and HepPar1 (5/5), shows cytoplasmic staining with TTF-1 (5/5) and does not express CK14 (0/5). Unlike hepatocellular carcinoma, it expresses CK5/6 (1/5), CK7 (3/5), CK19 (4/5), CK20 (1/5), HEA125 (5/5), MOC31 (5/5), monoclonal CEA (3/5) and napsin A (1/5). An immunohistochemical panel that includes a variety of cytokeratins, monoclonal CEA and EpCAM markers (HEA125 and MOC31) facilitates distinction of hepatoid adenocarcinoma of lung from hepatocellular carcinoma metastatic to lung, especially when correlated with clinical and radiologic findings. We propose modification of the current diagnostic criteria for hepatoid adenocarcinoma of lung. Tumor composition can be either pure hepatoid adenocarcinoma or hepatoid adenocarcinoma with components of typical acinar or papillary adenocarcinoma, signet-ring cells or neuroendocrine carcinoma. AFP expression is not requisite for diagnosis as long as other markers of hepatic differentiation are expressed.

Metabolic profiling identifies lung tumor responsiveness to erlotinib.

A subtype of non-small cell lung cancer, bronchioalveolar adenocarcinoma (BAC), is more prevalent in Asian female non-smokers, and is more likely to respond to treatment with tyrosine kinase inhibitors such as erlotinib and gefitinib. Nuclear magnetic resonance and mass spectrometry-based metabolomic analysis of extracts from two different lung lesions and surrounding non-cancerous tissues of a BAC patient showed novel protein and phospholipid-associated metabolic differences that correlated with tumor development as well as PET and erlotinib sensitivity.

Lung cancer screening: from imaging to biomarker

Despite several decades of intensive effort to improve the imaging techniques for lung cancer diagnosis and treatment, primary lung cancer is still the number one cause of cancer death in the United States and worldwide. The major causes of this high mortality rate are distant metastasis evident at diagnosis and ineffective treatment for locally advanced disease. Indeed, approximately forty percent of newly diagnosed lung cancer patients have distant metastasis. Currently, the only potential curative therapy is surgical resection of early stage lung cancer. Therefore, early detection of lung cancer could potentially increase the chance of cure by surgery and underlines the importance of screening and detection of lung cancer. In the past fifty years, screening of lung cancer by chest X-Ray (CXR), sputum cytology, computed tomography (CT), fluorescence endoscopy and low-dose spiral CT (LDCT) has not improved survival except for the recent report in 2010 by the National Lung Screening Trial (NLST), which showed a 20 percent mortality reduction in high risk participants screened with LDCT compared to those screened with CXRs. Furthermore, serum biomarkers for detection of lung cancer using free circulating DNA and RNA, exosomal microRNA, circulating tumor cells and various lung cancer specific antigens have been studied extensively and novel screening methods are being developed with encouraging results. The history of lung cancer screening trials using CXR, sputum cytology and LDCT, as well as results of trials involving various serum biomarkers, are reviewed herein.

Human polymorphonuclear neutrophils specifically recognize and kill cancerous cells.

Polymorphonuclear neutrophils (PMNs), the main effectors of the innate immune system, have rarely been considered as an anticancer therapeutic tool. However, recent investigations using animal models and preliminary clinical studies have highlighted the potential antitumor efficacy of PMNs. In the current study, we find that PMNs from some healthy donors naturally have potent cancer-killing activity against 4 different human cancer cell lines. The killing activity appears to be cancer cell-specific since PMNs did not kill primary normal epithelial cells or an immortalized breast epithelial cell line. Transfecting the immortalized mammary cells with plasmids expressing activated forms of the rat sarcoma viral oncogene homolog (Ras) and teratocarcinoma oncogene 21 (TC21) oncogenes was sufficient to provoke aggressive attack by PMNs. However, transfection with activated Ras-related C3 botulinum toxin substrate (Rac1) was ineffective, suggesting specificity in PMN-targeting of neoplastic cells. Furthermore, PMNs from lung cancer patients were also found to exhibit relatively poor cancer-killing activity compared to the cytolytic activity of the average healthy donor. Taken together, our results suggest that PMN-based treatment regimens may represent a paradigm shift in cancer immunotherapy that may be easily introduced into the clinic to benefit a subset of patients with PMN-vulnerable tumors.