41 research outputs found
c-FLIP Degradation Mediates Sensitization of Pancreatic Cancer Cells to TRAIL-Induced Apoptosis by the Histone Deacetylase Inhibitor LBH589
Great efforts have been made to develop novel and efficacious therapeutics against pancreatic cancer to improve the treatment outcomes. Tumor-necrosis factor-related apoptosis-inducing ligand (TRAIL) is such a therapeutic cytokine with selective killing effect toward malignant cells. However, some human pancreatic cancers are intrinsically resistant to TRAIL-mediated apoptosis or therapy. In this study, we have shown that the histone deacetylase inhibitor LBH589 can synergize with TRAIL to augment apoptosis even in TRAIL-resistant cells. LBH589 decreased c-FLIP levels in every tested cell line and survivin levels in some of the tested cell lines. Enforced expression of ectopic c-FLIP, but not survivin, abolished the cooperative induction of apoptosis by the combination of LBH589 and TRAIL, indicating that c-FLIP downregulation plays a critical role in LBH589 sensitization of pancreatic cancer cells to TRAIL. Moreover, LBH589 decreased c-FLIP stability and the presence of the proteasome inhibitor MG132 prevented c-FLIP from reduction by LBH589. Correspondingly, we detected increased levels of ubiqutinated c-FLIP in LBH589-treated cells. These data thus indicate that LBH589 promotes ubiqutin/proteasome-mediated degradation of c-FLIP, leading to downregulation of c-FLIP. Collectively, LBH589 induces c-FLIP degradation and accordingly sensitizes pancreatic cancer cells to TRAIL-induced apoptosis, highlighting a novel therapeutic regimen against pancreatic cancer
Mantle cell lymphoma of the gastrointestinal tract presenting with multiple intussusceptions – case report and review of literature
<p>Abstract</p> <p>Background</p> <p>Mantle cell lymphoma (MCL) is an aggressive type of B-cell non-Hodgkin's lymphoma that originates from small to medium sized lymphocytes located in the mantle zone of the lymph node. Extra nodal involvement is present in the majority of cases, with a peculiar tendency to invade the gastro-intestinal tract in the form of multiple lymphomatous polyposis. MCL can be accurately diagnosed with the use of the highly specific marker Cyclin D1. Few cases of mantle cell lymphoma presenting with intussuception have been reported. Here we present a rare case of multiple intussusceptions caused by mantle cell lymphoma and review the literature of this disease.</p> <p>Case presentation</p> <p>A 68-year-old male presented with pain, tenderness in the right lower abdomen, associated with nausea and non-bilious vomiting. CT scan of abdomen revealed ileo-colic intussusception. Laparoscopy confirmed multiple intussusceptions involving ileo-colic and ileo-ileal segments of gastrointestinal tract. A laparoscopically assisted right hemicolectomy and extended ileal resection was performed. Postoperative recovery was uneventful. The histology and immuno-histochemistry of the excised small and large bowel revealed mantle cell lymphoma with multiple lymphomatous polyposis and positivity to Cyclin D1 marker. The patient was successfully treated with Rituximab-CHOP chemotherapy and remains in complete remission at one-year follow-up.</p> <p>Conclusion</p> <p>This is a rare case of intestinal lymphomatous polyposis due to mantle cell lymphoma presenting with multiple small bowel intussusceptions. Our case highlights laparoscopic-assisted bowel resection as a potential and feasible option in the multi-disciplinary treatment of mantle cell lymphoma.</p
Fractionated radioimmunotherapy with 90Y-clivatuzumab tetraxetan and low-dose gemcitabine is active in advanced pancreatic cancer: A phase 1 trial
It has been demonstrated that the humanized clivatuzumab tetraxetan (hPAM4) antibody targets pancreatic ductal carcinoma selectively. After a trial of radioimmunotherapy that determined the maximum tolerated dose of single-dose yttrium-90-labeled hPAM4 (90Y-hPAM4) and produced objective responses in patients with advanced pancreatic ductal carcinoma, the authors studied fractionated radioimmunotherapy combined with low-dose gemcitabine in this disease
31st Annual Meeting and Associated Programs of the Society for Immunotherapy of Cancer (SITC 2016) : part two
Background
The immunological escape of tumors represents one of the main ob- stacles to the treatment of malignancies. The blockade of PD-1 or CTLA-4 receptors represented a milestone in the history of immunotherapy. However, immune checkpoint inhibitors seem to be effective in specific cohorts of patients. It has been proposed that their efficacy relies on the presence of an immunological response. Thus, we hypothesized that disruption of the PD-L1/PD-1 axis would synergize with our oncolytic vaccine platform PeptiCRAd.
Methods
We used murine B16OVA in vivo tumor models and flow cytometry analysis to investigate the immunological background.
Results
First, we found that high-burden B16OVA tumors were refractory to combination immunotherapy. However, with a more aggressive schedule, tumors with a lower burden were more susceptible to the combination of PeptiCRAd and PD-L1 blockade. The therapy signifi- cantly increased the median survival of mice (Fig. 7). Interestingly, the reduced growth of contralaterally injected B16F10 cells sug- gested the presence of a long lasting immunological memory also against non-targeted antigens. Concerning the functional state of tumor infiltrating lymphocytes (TILs), we found that all the immune therapies would enhance the percentage of activated (PD-1pos TIM- 3neg) T lymphocytes and reduce the amount of exhausted (PD-1pos TIM-3pos) cells compared to placebo. As expected, we found that PeptiCRAd monotherapy could increase the number of antigen spe- cific CD8+ T cells compared to other treatments. However, only the combination with PD-L1 blockade could significantly increase the ra- tio between activated and exhausted pentamer positive cells (p= 0.0058), suggesting that by disrupting the PD-1/PD-L1 axis we could decrease the amount of dysfunctional antigen specific T cells. We ob- served that the anatomical location deeply influenced the state of CD4+ and CD8+ T lymphocytes. In fact, TIM-3 expression was in- creased by 2 fold on TILs compared to splenic and lymphoid T cells. In the CD8+ compartment, the expression of PD-1 on the surface seemed to be restricted to the tumor micro-environment, while CD4 + T cells had a high expression of PD-1 also in lymphoid organs. Interestingly, we found that the levels of PD-1 were significantly higher on CD8+ T cells than on CD4+ T cells into the tumor micro- environment (p < 0.0001).
Conclusions
In conclusion, we demonstrated that the efficacy of immune check- point inhibitors might be strongly enhanced by their combination with cancer vaccines. PeptiCRAd was able to increase the number of antigen-specific T cells and PD-L1 blockade prevented their exhaus- tion, resulting in long-lasting immunological memory and increased median survival
GBR1302: Effect of CD3-HER2, a bispecific T cell engager antibody, in trastuzumab-resistant cancers.
Examining racial disparities in colorectal cancer care.
African Americans are disproportionately burdened with colorectal cancer. Although incidence and mortality rates have declined in the past two decades, the disparity in health outcomes has progressively increased. This comprehensive review examines the existing literature regarding racial disparities in colorectal cancer screening, stage at diagnosis, and treatment to determine if differences exist in the quality of care delivered to African Americans. A comprehensive review of relevant literature was performed. Two databases (EBSCOHOST Academic Search Premier and Scopus) were searched from 2000 to 2007. Articles that assessed racial disparities in colorectal cancer screening, stage of disease at diagnosis, and treatment were selected. The majority of studies identified examined colorectal cancer screening outcomes. Although racial disparities in screening have diminished in recent years, African American men and women continue to have higher colorectal cancer incidence and mortality rates and are diagnosed at more advanced stages. Several studies regarding stage of disease at diagnosis identified socioeconomic status (SES) and health insurance status as major determinants of disparity. However, some studies found significant racial disparities even after controlling for these factors. Racial disparities in treatment were also found at various diagnostic stages. Many factors affecting disparities between African Americans and Whites in colorectal cancer incidence and mortality remain unexplained. Although the importance of tumor biology, genetics, and lifestyle risk factors have been established, prime sociodemographic factors need further examination to understand variances in the care of African Americans diagnosed with colorectal cancer