Isolation and characterization of a CD34+ sub-clone in B-cell lymphoma.

Non-Hodgkin's lymphoma (NHL) is the most common hematological malignancy in the US. Many types remain incurable despite response to initial therapy and achievement of complete remission (CR). Advanced laboratory techniques like multicolor flow cytometry (FCM) and polymerase chain reaction (PCR) have demonstrated persistence of rare malignant cell population post therapy. However, the functional and biological characteristics of this population have not been elucidated. Established B-lymphoma cell lines (B-NHL) and patient-derived samples (PDS) were analyzed using 8-color FCM. CD34+ sub-population was enriched using in vitro exposure to 2-chlorodeoxyadenosine (2-CdA) and by CD34 magnetic beads. Genetic analysis of cell fractions was done by karyotyping and array comparative genomic hybridization (aCGH). Sensitivity to chemotherapy was assayed by short-term in vitro exposure to chemotherapy. Clonogenicity was determined by soft agar colony formation assay, and proliferation was determined using DNA staining with propidium iodide and FCM. FCM demonstrated the presence of a minute sub-clone of monotypic B-cells that express CD34 in B-NHL cell lines (3 of 3) and in PDS (8 of 8). This sub-population enriched up to 50 fold in vitro by exposure to 2-CdA and up to 80% purity by CD34 magnetic bead column isolation. Except for CD34 expression, this population expressed identical phenotype and genotype to parent cells, but was more proliferative, Hoechst 33342-positive, clonogenic, and resistant to chemotherapy compared with the CD34- population. The isolated CD34+ monotypic B-cells may contribute to resistance of certain NHL to treatment and should be targeted by potential new drugs for NHL.

Bilateral Triple-Negative Invasive Breast Cancer with a BRCA2 Mutation, and Glioblastoma: A Case Report and Literature Review.

Breast cancer is the second leading cause of death among women in North America. Glioblastoma is the most common primary malignant central nervous system tumor in adults. The majority of hereditary breast cancers are associated with deleterious mutations in the BRCA1 and BRCA2 genes. Although few case reports have described the incidence of glioblastoma in patients previously diagnosed with breast cancer, any association between BRCA2 mutations and glioblastoma has not been demonstrated to date. Herein, we report a woman who is a carrier of a familial BRCA2 mutation, and was previously diagnosed with triple-negative breast cancer (TNBC) and subsequently with a second primary TNBC and glioblastoma. Further investigation is required to define the possible relationship between these two aggressive malignances and the BRCA2 mutation, which might be critical for the proper management and treatment of this disease.

Prospect of the use of checkpoint inhibitors in hepatocellular cancer treatments.

Hepatocellular cancer (HCC) is a very fatal disease due to limited therapeutic options as well as due to its association with underlying chronic liver disease in the majority of cases. The immune evasion in HCC signifies a major barrier to the delivery of effective immunotherapy. Sorafenib is the only Food and Drug Administration-approved drug available with an overall response rate of 2%-3% and overall survival of 2.8 months. Chemotherapy has not been used routinely because of the relative refractoriness of advanced HCC. The introduction of immune checkpoint inhibitors (cytotoxic T-lymphocyte antigen 4, programmed death 1, and programmed death-ligand 1) has opened a new horizon for cancer immunotherapy. Future direction in immunotherapy for HCC is to rationally combine it with other treatment modalities, including surgery, radiofrequency ablation, and cytotoxic agents, to maximize its therapeutic efficacy.

Relapsed Acinic Cell Carcinoma of the Parotid Gland With Diffuse Distant Metastasis: Case Report With Literature Review.

Acinic cell carcinoma (ACC) is an uncommon salivary gland neoplasm that generally displays an indolent growth pattern. Most cases arise in the major glands, particularly the parotid. However, it can arise from minor salivary glands in the oral cavity and aero-digestive tract. Although ACC is generally a low-grade malignant tumor, poorly differentiated and high-grade transformed variants exhibit a propensity for late recurrence and metastasis. There are no adequate clinical trials that define the optimal approach to patients with metastatic salivary gland tumors due to its rarity. Systemic therapy is reserved for cases where local therapy, such as radiation or metastasectomy, is not appropriate. Nevertheless, there is insufficient data in the literature regarding the chemotherapy of choice for metastatic ACC. In this article, we report a case of metastatic ACC of the right parotid gland that progressed on carboplatin and paclitaxel after partial response followed by doxorubicin and is currently on checkpoint inhibitor treatment.

Primary Retroperitoneal Melanoma Presented in a Rare Extracutaneous Site for Malignant Melanoma.

Malignant melanoma, as the name implies, is a malignant tumor of melanocytes, found in the skin, eyes, meningeal lining and the mucosal epithelium of the aero-digestive and genitourinary tracts. Malignant melanoma is typically skin malignancy, which rarely presents at extracutaneous site. Here we present a rare case of primary retroperitoneal melanoma and review the findings in comparison with other cases described in literature.

Hematologic malignancies: newer strategies to counter the BCL-2 protein.

INTRODUCTION: BCL-2 is the founding member of the BCL-2 family of apoptosis regulatory proteins that either induce (pro-apoptotic) or inhibit (anti-apoptotic) apoptosis. The anti-apoptotic BCL-2 is classified as an oncogene, as damage to the BCL-2 gene has been shown to cause a number of cancers, including lymphoma. Ongoing research has demonstrated that disruption of BCL-2 leads to cell death. BCL-2 is also known to be involved in the development of resistance to chemotherapeutic agents, further underscoring the importance of targeting the BCL-2 gene in cancer therapeutics. Thus, numerous approaches have been developed to block or modulate the production of BCL-2 at the RNA level using antisense oligonucleotides or at the protein level with BCL-2 inhibitors, such as the novel ABT737. METHODS: In this article, we briefly review previous strategies to target the BCL-2 gene and focus on a new approach to silence DNA, DNA interference (DNAi). RESULTS AND CONCLUSION: DNA interference is aimed at blocking BCL-2 gene transcription. Evaluations of this technology in preclinical and early clinical studies are very encouraging and strongly support further development of DNAi as cancer therapeutics. A pilot phase II clinical trial in patients with relapsed or refractory non-Hodgkin lymphoma, PNT2258 demonstrated clinical benefit in 11 of 13 patients with notable responses in diffuse large B cell lymphoma and follicular lymphoma. By targeting the DNA directly, the DNAi technology promises to be more effective compared with other gene-interference strategies that target the RNA or protein but leaves the dysregulated DNA functional.

Safety and efficacy of radioimmunotherapy (RIT) in treatment of non-Hodgkin's lymphoma in the community setting.

INTRODUCTION: Radioimmunotherapy (RIT) is a unique therapeutic modality that combines biologic and radiolytic mechanisms to induce tumor kill. RIT is underutilized in the community outpatient setting. METHODS: This is an institutional review of patients treated with RIT at St. John Hospital and Medical Center (SJH&MC) 2003-2011. RIT agents were dosed according to recommended guidelines. Response was assessed using the Revised Response Criteria for Malignant Lymphoma and toxicity was assessed using the National Cancer Institute Common Terminology Criteria for Adverse Events. The primary aim was to assess overall response rate (ORR) and overall survival (OS). The secondary aim was to assess the impact of variable host and disease factors on the ORR to RIT and OS. RESULTS: Forty-eight patients were treated with RIT within the specified period at SJH&MC; of which 52% with follicular lymphoma (FL) and 46% with diffuse large B cell lymphoma (DLBCL). The majority of patients had relapsed or refractory disease (98%). Median duration of follow-up was 17 months. The ORR was 73% with 44% complete remission (CR) rate and OS of 48 months. The ORR was 79% with 58% CR rate and OS of 82 months among FL patients. Among DLBCL patients, the ORR was 65% with 30% CR rate and OS of 39 months. Response to last therapy before RIT was the only significant predictor of response to RIT and a significant predictor of OS in multivariate analyses. Prior exposure to EBRT did not predict response or survival in multivariate analyses. Toxicity was manageable and predominantly hematologic. CONCLUSIONS: RIT is effective and feasible for use in the community outpatient setting. ADVANCES IN KNOWLEDGE AND IMPLICATIONS FOR PATIENT CARE: Patients with B-cell NHL can safely receive RIT close to home. With some coordination of effort, it is not difficult for community-based cancer centers to implement this treatment modality.

Leukemia cutis in a patient with chronic lymphocytic leukemia presenting as bilateral helical nodules.

Chronic lymphocytic leukemia, the most common adult leukemia worldwide, is considered an indolent but incurable non-Hodgkin lymphoma. Leukemia cutis is an uncommon manifestation of chronic lymphocytic leukemia. We present a case of an adult patient who presented with skin lesion of bilateral ears, which led to the diagnosis of chronic lymphocytic leukemia. We also reviewed the cases of auricular involvement in chronic lymphocytic leukemia patients reported in the literature. Local treatment is indicated in case of leukemia cutis; however, systemic treatment is recommended when there are systemic signs and symptoms. Better awareness of disease evolution and prompt diagnosis of this leukemia cutis of chronic lymphocytic leukemia will improve the effectiveness and outcome of its management.

Acute Respiratory Distress Syndrome after Treatment of Metastatic Prostate Cancer with Taxotere: A Case Report and Literature Review.

Prostate cancer is the most common cancer in men. Docetaxel is a common chemotherapeutic agent that has proven its efficacy in the treatment of patients with both castration sensitive and resistant metastatic prostate cancer. We report a case of acute respiratory distress syndrome (ARDS) in a patient with metastatic prostate cancer treated with docetaxel (Taxotere). ARDS is very rare but life threatening complication of docetaxel which requires aggressive supportive care and close monitoring. Better awareness and prompt diagnosis of this treatment related ARDS will improve the effectiveness and outcome of its management.

Modulation of deoxycytidine kinase (dCK) and glycogen synthase kinase (GSK-3ß) by anti-CD20 (rituximab) and 2-chlorodeoxyadenosine (2-CdA) in human lymphoid malignancies.

BACKGROUND: The combination of rituximab and 2-CdA is an effective therapy for B-cell tumors. However, the molecular mechanisms and enzymatic pathways involved in the interaction between the two agents are not fully understood. In this study, we provide molecular evidence for positive interaction between these two agents with resultant therapeutic benefit. METHODS: Efficacy of the R-2CdA regimen was evaluated in thirteen patients with B-cell tumors (9 CLL; 3 WM and 1 FL), in vitro against 3 lymphoma cell lines and in a xenograft mouse model. Treatment-induced changes involving phenotype, kinase activity and protein expression were assessed in vitro and in the mouse xenograft tumors. The interaction between RTX and 2-CdA was analyzed using the multiple comparison method, Tukey's honestly significant difference (HSD). For the clinical and animal data, survival functions were estimated using the Kaplan-Meier method and compared by the log-rank test. P-values <0.05 were considered statistically significant. All statistical analyses were evaluated using GraphPad Prism 4 (San Diego, CA). RESULTS: 9 of 12 (75%) evaluable patients responded to the R-2-CdA regimen with median duration of response of 34 months. Median survival of patients from diagnosis and from completion of R-2-CdA treatment was 13.3 and 7.9 years, respectively. In vitro, the combination was effective in all 3 cell lines of lymphomas but with higher sensitivity in the follicular lymphoma cell line. The combination was also effective in the WSU-WM-SCID xenograft model with dose-dependent response and synergistic benefit. All animals were tumor-free for up to 120 days post 2 cycles of this regimen. Rituximab induced activation of deoxycytidine kinase (dCK), p38 mitogen activated protein kinase (p38MAPK) and glycogen synthase kinase-3ß (GSK-3ß) in the xenograft WSU-WM tumors. Chemical inhibition of p38MAPK led to inhibition of the GSK-3ß phosphorylation suggesting that GSK-3ß is regulated by p38MAPK in this model. CONCLUSION: Collectively, our studies show concordance between the activity of R-2-CdA in vitro, in human and in WSU-WM xenograft model attesting to the validity of this model in predicting clinical response. Modulation of dCK and GSK-3ß by rituximab may contribute to the positive therapeutic interaction between rituximab and 2-CdA.

Targeting CD19 in B-cell lymphoma: emerging role of SAR3419.

Non-Hodgkin lymphoma symbolizes a heterogeneous group of diseases resulting from malignant transformation of lymphocytes with differing patterns of behavior and responses to treatment. The potential curability of non-Hodgkin lymphoma differs among the various histologic subtypes and is associated in part with the stage at presentation. CD19 antigen is a type I transmembrane glycoprotein belonging to the immunoglobulin Ig superfamily. CD19 is specifically expressed in normal and neoplastic B-cells. Recent study showed that in a mouse model, CD19 and c-Myc synergize functionally to accelerate B-cell lymphomagenesis, which is associated with increased disease severity. Specificity is the most important challenge in cancer therapeutics. Antibody-drug conjugates have the prospect of enhancing the therapeutic efficacy over unconjugated monoclonal antibodies through the selective delivery of cytotoxic agents to cancer cells. The ubiquitous expression of CD19 in these tumors, especially at an earlier stage and the property of efficient internalization, makes CD19 an attractive and affective target for antibody-drug conjugate therapy as compared to CD20. SAR3419 (huB4-DM4) is a novel antibody-drug conjugate that is composed of a humanized monoclonal IgG1 anti-CD19 antibody (huB4) attached to the potent cytotoxic drug, a maytansine derivative (DM4), through a cleavable disulfide cross-linking agent N-Succinimidyl-4-2-pyridyldithio butanoic acid (SPDB). The preclinical efficacy of maytansine derivative-anti-CD19 conjugate was demonstrated in our laboratory, and SAR3419 was found to be more effective than CHOP in a xenograft model. Phase I trials have also been conducted on the basis of preclinical studies that demonstrated promising antitumor activity with acceptable safety results in human B-cell lymphoma models. Additional trials are ongoing and will provide additional insight into the full potential of this novel drug.

Apocrine carcinoma of the face in a 62-year-old Asian man.

Apocrine carcinoma (AC) is a rare tumor with heterogeneous presentation. The disease has a highly morbid course and little is known about it. We present an otherwise healthy, 62-year-old Asian male who originally presented with chronic swelling of his left eyelid associated with excessive tears and diminished vision was diagnosed with AC. AC is often challenging to diagnose, yet it is critical to do so as early diagnosis and treatment can maximize patient survival.