Ruth L. Katz

Aldehyde dehydrogenase 1 is a tumor stem cell-Associated marker in lung cancer

Tumor contains small population of cancer stem cells (CSC) that are responsible for its maintenance and relapse. Analysis of these CSCs may lead to effective prognostic and therapeutic strategies for the treatment of cancer patients. We report here the identification of CSCs from human lung cancer cells using Aldefluor assay followed by fluorescence-activated cell sorting analysis. Isolated cancer cells with relatively high aldehyde dehydrogenase 1 (ALDH1) activity display in vitro features of CSCs, including capacities for proliferation, self-renewal, and differentiation, resistance to chemotherapy, and expressing CSC surface marker CD133. In vivo experiments show that the ALDH1-positive cells could generate tumors that recapitulate the heterogeneity of the parental cancer cells. Immunohistochemical analysis of 303 clinical specimens from three independent cohorts of lung cancer patients and controls show that expression of ALDH1 is positively correlated with the stage and grade of lung tumors and related to a poor prognosis for the patients with early-stage lung cancer. ALDH1 is therefore a lung tumor stem cell-associated marker. These findings offer an important new tool for the study of lung CSCs and provide a potential prognostic factor and therapeutic target for treatment of the patients with lung cancer. (Mol Cancer Res 2009;7(3):330–8)

High Rate of Durable Remissions After Treatment of Newly Diagnosed Aggressive Mantle-Cell Lymphoma With Rituximab Plus Hyper-CVAD Alternating With Rituximab Plus High-Dose Methotrexate and Cytarabine

PURPOSE To determine the response, failure-free survival (FFS), and overall survival rates and toxicity of rituximab plus an intense chemotherapy regimen in patients with previously untreated aggressive mantle-cell lymphoma (MCL). PATIENTS AND METHODS This was a prospective phase II trial of rituximab plus fractionated cyclophosphamide, vincristine, doxorubicin, and dexamethasone (hyper-CVAD; considered one cycle) alternating every 21 days with rituximab plus high-dose methotrexate-cytarabine (considered one cycle) for a total of six to eight cycles. RESULTS Of 97 assessable patients, 97% responded, and 87% achieved a complete response (CR) or unconfirmed CR. With a median follow-up time of 40 months, the 3-year FFS and overall survival rates were 64% and 82%, respectively, without a plateau in the curves. For the subgroup of patients < or = 65 years of age, the 3-year FFS rate was 73%. The principal toxicity was hematologic. Five patients died from acute toxicity. Four patients developed treatment-related myelodysplasia/acute myelogenous leukemia, and three patients died while in remission from MCL. A total of eight treatment-related deaths (8%) occurred. CONCLUSION Rituximab plus hyper-CVAD alternating with rituximab plus high-dose methotrexate and cytarabine is effective in untreated aggressive MCL. Toxicity is significant but expected. Because of the shorter FFS concurrent with significant toxicity in patients more than 65 years of age, this regimen is not recommended as standard therapy for this age subgroup. Larger prospective randomized studies are needed to define the role of this regimen in the treatment of MCL patients compared with existing and new treatment modalities.

Early detection of lung adenocarcinoma in sputum by a panel of microRNA markers

Adenocarcinoma is the most common type of lung cancer, the leading cause of cancer deaths in the world. Early detection is the key to improve the survival of lung adenocarcinoma patients. We have previously shown that microRNAs (miRNAs) were stably present in sputum and could be applied to diagnosis of lung cancer. The aim of our study was to develop a panel of miRNAs that can be used as highly sensitive and specific sputum markers for early detection of lung adenocarcinoma. Our study contained 3 phases: (i) marker discovery using miRNA profiling on paired normal and tumor lung tissues from 20 patients with lung adenocarcinoma; (ii) marker optimization by real‐time reverse transcription‐quantitative polymerase chain reaction on sputum of a case–control cohort consisting of 36 cancer patients and 36 health individuals and (iii) validation on an independent set of 64 lung cancer patients and 58 cancer‐free subjects. From the surgical tissues, 7 miRNAs with significantly altered expression were identified, of which “4” were overexpressed and “3” were underexpressed in all 20 tumors. On the sputum samples of the case–control cohort, 4 (miR‐21, miR‐486, miR‐375 and miR‐200b) of the 7 miRNAs were selected, which in combination produced the best prediction in distinguishing lung adenocarcinoma patients from normal subjects with 80.6% sensitivity and 91.7% specificity. Validation of the marker panel in the independent populations confirmed the sensitivity and specificity that provided a significant improvement over any single one alone. The sputum markers demonstrated the potential of translation to laboratory settings for improving the early detection of lung adenocarcinoma.

Plasma microRNAs as potential biomarkers for non-small-cell lung cancer

Non-small-cell lung cancer (NSCLC) is the leading cause of cancer-related death. Developing minimally invasive techniques that can diagnose NSCLC, particularly at an early stage, may improve its outcome. Using microarray platforms, we previously identified 12 microRNAs (miRNAs) the aberrant expressions of which in primary lung tumors are associated with early-stage NSCLC. Here, we extend our previous research by investigating whether the miRNAs could be used as potential plasma biomarkers for NSCLC. We initially validated expressions of the miRNAs in paired lung tumor tissues and plasma specimens from 28 stage I NSCLC patients by real-time quantitative reverse transcription PCR, and then evaluated diagnostic value of the plasma miRNAs in a cohort of 58 NSCLC patients and 29 healthy individuals. The altered miRNA expressions were reproducibly confirmed in the tumor tissues. The miRNAs were stably present and reliably measurable in plasma. Of the 12 miRNAs, five displayed significant concordance of the expression levels in plasma and the corresponding tumor tissues (all r>0.850, all P<0.05). A logistic regression model with the best prediction was defined on the basis of the four genes (miRNA-21, -126, -210, and 486-5p), yielding 86.22% sensitivity and 96.55% specificity in distinguishing NSCLC patients from the healthy controls. Furthermore, the panel of miRNAs produced 73.33% sensitivity and 96.55% specificity in identifying stage I NSCLC patients. In addition, the genes have higher sensitivity (91.67%) in diagnosis of lung adenocarcinomas compared with squamous cell carcinomas (82.35%) (P<0.05). Altered expressions of the miRNAs in plasma would provide potential blood-based biomarkers for NSCLC.

Nonablative Allogeneic Stem-Cell Transplantation for Advanced/Recurrent Mantle-Cell Lymphoma

PURPOSE Patients with relapsed mantle-cell lymphoma have poor prognosis and short survival. Our aim was to determine the efficacy of nonablative allogeneic stem-cell transplantation in patients with relapsed mantle-cell lymphoma. PATIENTS AND METHODS Eighteen patients were treated in one of two consecutive trials. Thirteen patients underwent a conditioning regimen of fludarabine (30 mg/m2 daily for 3 days), cyclophosphamide (750 mg/m2 daily for 3 days), and high-dose rituximab. For the remaining five patients, the conditioning regimen consisted of cisplatin (25 mg/m2 daily for 4 days), fludarabine (30 mg/m2 daily for 2 days), and cytarabine (1,000 mg/m2 daily for 2 days). Tacrolimus and methotrexate were used for graft-versus-host disease prophylaxis. RESULTS The median age was 56.5 years. Patients underwent a median of three prior chemotherapy regimens. Prior autologous transplantation failed in five (28%) patients and 16 (89%) had chemosensitive disease. Donor cell engraftment occurred in all patients. Eight patients (44%) required no platelet or RBC transfusion, and acute graft-versus-host disease of greater than grade 2 did not develop in any patient. The day-100 mortality was 0%. Complete remission (CR) occurred in 17 patients. Three patients progressed, and one was reinduced into continuous CR with donor lymphocyte infusion. With a median follow-up period of 26 months, the actuarial probability of current-event-free-survival at 3 years was 82% (95% CI, 65% to 99%). CONCLUSION Our data suggest that nonablative allogeneic transplantation is a safe and potentially effective strategy for patients with relapsed and chemosensitive mantle-cell lymphoma.

Cationic liposome-mediated E1A gene transfer to human breast and ovarian cancer cells and its biologic effects : a phase I clinical trial

PURPOSE Preclinical studies have demonstrated that the adenovirus type 5 E1A gene is associated with antitumor activities by transcriptional repression of HER-2/neu and induction of apoptosis. Indeed, E1A gene therapy is known to induce regression of HER-2/neu-overexpressing breast and ovarian cancers in nude mice. Therefore, we evaluated the feasibility of intracavitary injection of E1A gene complexed with DC-Chol cationic liposome (DCC-E1A) in patients with both HER-2/neu-overexpressing and low HER-2/neu-expressing breast and ovarian cancers in a phase I clinical trial. PATIENTS AND METHODS An E1A gene complexed with DCC-E1A cationic liposome was injected once a week into the thoracic or peritoneal cavity of 18 patients with advanced cancer of the breast (n = 6) or ovary (n = 12). RESULTS E1A gene expression in tumor cells was detected by immunohistochemical staining and reverse transcriptase-polymerase chain reaction. This E1A gene expression was accompanied by HER-2/neu downregulation, increased apoptosis, and reduced proliferation. The most common treatment-related toxicities were fever, nausea, vomiting, and/or discomfort at the injection sites. CONCLUSION These results argue for the feasibility of intracavitary DCC-E1A administration, provide a clear proof of preclinical concept, and warrant phase II trials to determine the antitumor activity of the E1A gene.

PTEN genomic deletion is associated with p-Akt and AR signalling in poorer outcome, hormone refractory prostate cancer

PTEN haploinsufficiency is common in hormone‐sensitive prostate cancer, though the incidence of genomic deletion and its downstream effects have not been elucidated in clinical samples of hormone refractory prostate cancer (HRPC). Progression to androgen independence is pivotal in prostate cancer and mediated largely by the androgen receptor (AR). Since this process is distinct from metastatic progression, we examined alterations of the PTEN gene in locally advanced recurrent, non‐metastatic human HRPC tissues. Retrospective analyses of PTEN deletion status were correlated with activated downstream phospho‐Akt (p‐Akt) pathway proteins and with the androgen receptor. The prevalence of PTEN genomic deletions in transurethral resection samples of 59 HRPC patients with known clinical outcome was assessed by four‐colour FISH analyses. FISH was performed using six BAC clones spanning both flanking PTEN genomic regions and the PTEN gene locus, and a chromosome 10 centromeric probe. PTEN copy number was also evaluated in a subset of cases using single nucleotide polymorphism (SNP) arrays. In addition, the samples were immunostained with antibodies against p‐Akt, p‐mTOR, p‐70S6, and AR. The PTEN gene was deleted in 77% of cases, with 25% showing homozygous deletions, 18% homozygous and hemizygous deletions, and 34% hemizygous deletions only. In a subset of the study group, SNP array analysis confirmed the FISH findings. PTEN genomic deletion was significantly correlated to the expression of downstream p‐Akt (p < 0.0001), AR (p = 0.025), and to cancer‐specific mortality (p = 0.039). PTEN deletion is common in HRPC, with bi‐allelic loss correlating to disease‐specific mortality and associated with Akt and AR deregulation. Copyright

Fine-needle aspiration of 154 parotid masses with histologic correlation. Ten-year experience at the University of Texas M.D. Anderson Cancer Center

BACKGROUND Clinical and radiologic assessment of parotid masses cannot distinguish reliably between benign and malignant lesions. The utility of fine-needle aspiration (FNA) of parotid masses at a cancer referral center (where clinicians may be especially adept at diagnosing parotid gland malignancies) remains controversial. METHODS Between January 1986 and June 1996, 482 parotid glands were resected at the University of Texas, M. D. Anderson Cancer Center (MDACC). A preoperative FNA result was available for 147 of these resections (30%), (corresponding to 154 preoperative FNAs). The results of 154 consecutive preoperative FNAs were compared with the corresponding histopathologic diagnoses. RESULTS Histologic evaluation revealed 76 malignant tumors and 78 benign lesions (67 neoplastic and 11 nonneoplastic). The FNA smear was nondiagnostic in two benign and two malignant cases. The cytologic diagnosis was true-positive in 61 cases (82% sensitivity), and true-negative in 65 cases (86% specificity). There were 11 false-positive results. Eight of these cases were classified as false-positive because they were suspicious for malignancy; five of the eight were outside cases. In addition, there were 13 false-negative results (6 metastatic lesions, 3 low grade mucoepidermoid carcinomas, 2 acinic cell carcinomas, and 2 carcinoma ex pleomorphic adenomas) (9%). Fifty-one of the malignant lesions (84%) and 60 of the benign lesions (92%), including 93% of the benign tumors, were classified accurately. Ten of ten lymphoma cases in this series were identified correctly. CONCLUSIONS FNA of parotid masses at a major referral cancer center has a sensitivity of 82%, a specificity of 86%, and an overall diagnostic accuracy of 84%. FNA plays an important role in the preoperative and postoperative assessment of parotid masses by aiding in the evaluation of tumors in poor surgical candidates and unresectable tumors, and by identifying metastases from other sites, reticuloendothelial tumors, and nonneoplastic inflammatory conditions.

Comparison of quantification of histochemical staining by hue-saturation-intensity (HSI) transformation and color-deconvolution.

We tested a recently developed flexible method of separation and quantification of immunohistochemical staining by means of color image analysis. An algorithm was recently developed to deconvolve the color information acquired with RGB cameras, to calculate the contribution of each of the applied stains, based on the stain-specific RGB absorption. The algorithm was tested using a set of lung-tumor samples labeled for the detection of Ki-67, an antigen expressed in proliferating cells, covering a wide range of staining levels. Quantification of the labeling was compared with HSI-based segmentation and manual analysis of the same samples. The recently developed deconvolution method performed significantly better than the HSI based system when compared to manual counting as gold standard. The deconvolution system showed significantly reduced variability in the LI determination, especially of highly labeled control samples. This resulted in significant increase in sensitivity of classification of samples with increased KI-67 labeling without changing the specificity, when compared to the HSI based method.

Small nucleolar RNA 42 acts as an oncogene in lung tumorigenesis

Non-small cell lung cancer (NSCLC) is the leading cause of cancer death, reflecting the need for better understanding the oncogenesis, and developing new diagnostic and therapeutic targets for the malignancy. Emerging evidence suggests that small nucleolar RNAs (snoRNAs) have malfunctioning roles in tumorigenesis. Our recent study demonstrated that small nucleolar RNA 42 (SNORA42) was overexpressed in lung tumors. Here, we investigate the role of SNORA42 in tumorigenesis of NSCLC. We simultaneously assess genomic dosages and expression levels of SNORA42 and its host gene, KIAA0907, in 10 NSCLC cell lines and a human bronchial epithelial cell line. We then determine in vitro functional significance of SNORA42 in lung cancer cell lines through gain- and loss-of-function analyses. We also inoculate cancer cells with SNORA42-siRNA into mice through either tail vein or subcutaneous injection. We finally evaluate expression level of SNORA42 on frozen surgically resected lung tumor tissues of 64 patients with stage I NSCLC by using quantitative reverse transcriptase PCR assay. Genomic amplification and associated high expression of SNORA42 rather than KIAA0907 are frequently observed in lung cancer cells, suggesting that SNORA42 overexpression is activated by its genomic amplification. SNORA42 knockdown in NSCLC cells inhibits in vitro and in vivo tumorigenicity, whereas enforced SNORA42 expression in bronchial epitheliums increases cell growth and colony formation. Such pleiotropy of SNORA42 suppression could be achieved at least partially through increased apoptosis of NSCLC cells in a p53-dependent manner. SNORA42 expression in lung tumor tissue specimens is inversely correlated with survival of NSCLC patients. Therefore, SNORA42 activation could have an oncogenic role in lung tumorigenesis and provide potential diagnostic and therapeutic targets for the malignancy.