Slippery Nanoparticles as a Diffusion Platform for Mucin Producing Gastrointestinal Tumors.

BACKGROUND: Treatment failure in pseudomyxoma peritonei (PMP) is partly attributed to the ineffective delivery of therapeutics through dense mucinous tumor barriers. We modified the surface of Poly (lactic-co-glycolic acid)-b-polyethylene glycol (PLGA-PEG-NPs) with a low-density, second PEG layer (PLGA-TPEG-NPs-20) to reduce their binding affinity to proteins and improve diffusion through mucin. METHODS: Nanoprecipitation was used to fabricate PLGA-PEG-NPs. To construct the second PEG layer of PLGA-TPEG-NPs-20, PEG-Thiol was conjugated to PLGA-PEG-NPs composed of 80% methoxy PLGA-PEG and 20% of PLGA-PEG-Maleimide. DiD-labeled nanoparticles (NPs) were added to the inner well of a trans-well system containing cultured LS174T or human PMP tissue. Diffusion of NPs was measured via fluorescence signal in the bottom well. In an ex vivo rat model, small intestine was treated with DiD-labeled NPs. In an in vivo murine LS174T subcutaneous tumor model, Nu/Nu nude mice received supratumoral injections (subcutaneous injection above the tumor) of DiD-labeled NPs. Thirty minutes after injection, mice were sacrificed, and tumors were collected. All tissue was cryosectioned, mounted with DAPI-containing media, and inspected via confocal microscopy. RESULTS: Diffusion profiles of NPs through PMP and cultured LS174T cells were generated. PLGA-TPEG-NPs-20 diffused faster with ~ 100% penetration versus PLGA-PEG-NPs with ~ 40% penetration after 8 h. Increased diffusion of PLGA-TPEG-NPs-20 was further observed in ex vivo rat small intestine as evidenced by elevated luminal NP fluorescence signal on the luminal surface. Subcutaneous LS174T tumors treated with PLGA-TPEG-NPs-20 demonstrated greater diffusion of NPs, showing homogenous fluorescence signal throughout the tumor. CONCLUSIONS: PLGA-TPEG-NPs-20 can be an effective mucin penetrating drug delivery system.

Case report of rhabdomyosarcomatous transformation of a primary gastrointestinal stromal tumor (GIST).

BACKGROUND: Gastrointestinal stromal tumor (GIST) is the most common primary mesenchymal neoplasm of the gastrointestinal tract. Mutations of KIT and platelet-derived growth factor receptor alpha have been well characterized in GISTs. Patients with KIT mutations are generally sensitive to treatment with tyrosine kinase inhibitors. However, some patients with GIST, while initially sensitive to TKIs, gain resistance in later stages of treatment. Heterologous rhabdomyomsarcomatous dedifferentiation of advanced GISTs after long-term imatinib mesylate (IM) therapy has been reported. In these cases, the underlying molecular mechanism of tumor progression and transformation is unclear. CASE PRESENTATION: We report one such patient with rhabdomyosarcomatous dedifferentiation of a GIST without metastatic disease after brief 3-month therapy with IM. The tumor was composed of two distinct phenotypes, a CD117 negative region with rhabdomyosarcomatous differentiation directly adjacent to a CD117 positive classic GIST region. Molecular analysis identified the activating KIT exon 11 mutation in both regions, indicating a common origin for both phenotypes. Additionally, the dedifferentiated component contained two synonymous variants in platelet-derived growth factor receptor alpha and KIT. The increased number of synonymous variants in the rhabdomyosarcomatous region may reflect increased genetic instability of this tumor that may have resulted in the loss of CD117 expression in the dedifferentiated component. CONCLUSION: This study adds to the growing consensus that rhabdomyosarcomatous GIST progresses from a common GIST primary tumor. The role of IM in this progression is uncertain; however short duration of IM treatment in this study supports the hypothesis that rhabdomyosarcomatous GIST progression is not a consequence of IM therapy. Furthermore, we provide additional information supporting the observation that CD117 negative rhabdomyosarcomatous transformation maintains the activating KIT variant without KIT expression.

Non-Thermal Plasma-Induced Immunogenic Cell Death in Cancer: A Topical Review.

Recent advances in biomedical research in cancer immunotherapy have identified the use of an oxidative stress-based approach to treat cancers, which works by inducing immunogenic cell death (ICD) in cancer cells. Since the anti-cancer effects of non-thermal plasma (NTP) are largely attributed to the reactive oxygen and nitrogen species that are delivered to and generated inside the target cancer cells, it is reasonable to postulate that NTP would be an effective modality for ICD induction. NTP treatment of tumors has been shown to destroy cancer cells rapidly and, under specific treatment regimens, this leads to systemic tumor-specific immunity. The translational benefit of NTP for treatment of cancer relies on its ability to enhance the interactions between NTP-exposed tumor cells and local immune cells which initiates subsequent protective immune responses. This review discusses results from recent investigations of NTP application to induce immunogenic cell death in cancer cells. With further optimization of clinical devices and treatment protocols, NTP can become an essential part of the therapeutic armament against cancer.

Case report: optimal tumor cytoreduction and octreotide with durable disease control in a patient with MEN-1 and Zollinger-Ellison syndrome-over a decade of follow-up.

BACKGROUND: Zollinger-Ellison syndrome (ZES) is a rare condition characterized by hypersecretion of gastrin by gastrinoma tumors leading to severe peptic ulcer disease with potential development of gastric carcinoid tumors. Herein, we report the clinical course of a 68-year-old patient with multiple endocrine neoplasia type 1 (MEN-1) who underwent several surgeries to ultimately undergo optimal tumor cytoreduction of locally advanced gastrinomas and symptomatic gastric carcinoids. The patient was subsequently maintained on octreotide long-acting release (LAR). This case report supports consideration for aggressive tumor cytoreduction and octreotide in similar patients with MEN-1-associated ZES for durable disease control and symptom management. CASE PRESENTATION: The patient is a 68-year-old male with multiple endocrine neoplasia type 1 (MEN-1), diagnosed in 1993 after presenting with recurrent renal calculi and hypercalcemia. Soon thereafter, he presented with symptoms and elevated gastrin levels suggestive of ZES prompting abdominal exploration with partial resection of the duodenum to remove gastrinoma tumor nodules. Within 4 years of the operation, he represented with intractable hypergastrinemia despite optimal medical management with peak gastrin levels exceeding 29,000 pg/mL, in 2006. In January 2007, the patient returned to the operating room for resection of regional peripancreatic and perigastric lymph nodes and enucleation of pancreatic body and tail gastrinoma tumors. Although his gastrin level decreased to 5000 pg/mL with resultant improvement of symptoms, in less than 2 years, he developed disease progression with obstructive symptomatology from enlarging gastric carcinoids and rising gastrin levels. In May of 2008, he underwent pancreaticoduodenectomy and near-total gastrectomy. Since June of 2008, the patient shows no demonstrable progression of disease and remains asymptomatic on LAR octreotide (30 mgs). Gastrin levels have been well controlled (range, 100-624 pg/mL; current 114 pg/mL). CONCLUSION: Success of this procedure in our case report highlights the potential role for optimal tumor cytoreduction and LAR octreotide to control disease progression in a patient with MEN-I and Zollinger-Ellison syndrome with locally advanced gastrinoma and secondary large gastric carcinoids.

Multidisciplinary strategies in bloodless medicine and surgery for patients undergoing pancreatectomy.

BACKGROUND: Bloodless pancreatic surgery (BPS) is rarely performed and/or reported. We aim to characterize perioperative and anesthetic strategies in BPS. MATERIALS AND METHODS: A literature search was performed on MEDLINE looking for case reports/case series using search terms ("Jehovah's Witness" [All Fields]) AND ("Pancreatic Surgery" [All Fields] OR "Pancreaticoduodenectomy" [All Fields] OR "Distal Pancreatectomy" [All Fields]). Data regarding categorical variables are reported as proportions and quantitative continuous variables as medians with ranges or means with standard deviation. Forty-one patients requiring BPS are reported in the literature with three additional cases from our institution (n = 44). The data analyzed included clinicopathologic factors, BPS strategies, patient complications, and in-hospital mortality. RESULTS: The most common procedure and diagnosis were pancreaticoduodenectomy (n = 34, 77.3%) and pancreatic ductal adenocarcinoma (n = 12, 27.3%), respectively. Transfusion reduction strategies in BPS fell into three categories: preoperative, intraoperative, and postoperative. Preoperative strategies included iron supplementation (n = 24, 54.5%) and erythropoietin administration (n = 14, 41.2%). Intraoperative strategies included acute normovolemic hemodilution (n = 30, 68%) and cell saver (n = 4, 9.1%). Postoperative strategies included erythropoietin (n = 16, 48.5%) and iron supplementation (n = 16, 48.5%). Complications occurred in 21 (60%) patients. There was no in-hospital mortality among the 44 patients in this cohort. CONCLUSIONS: A broad spectrum of bloodless medicine and surgery practices were used based on patient selection, multidisciplinary practice, and preference. With careful perioperative and anesthetic management, BPS can be performed with good outcomes.

Clinical studies in CRS and HIPEC: Trials, tribulations, and future directions-A systematic review.

BACKGROUND: The field of cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) has suffered from a lack of clinical trials to validate its expanding use. OBJECTIVE: To evaluate published and ongoing clinical trials seeking to better define role of CRS/HIPEC in the treatment of peritoneal surface malignancies. METHODS: Systematic review by PubMed search was performed using terms "Clinical trial," "intraperitoneal chemotherapy," and "HIPEC." ClinicalTrials.gov and EudraCT registries were searched for active clinical trials. Eligibility included CRS/HIPEC trials investigating adult patient populations from published clinical reports and/or trials currently accruing or at completion. RESULTS: Thirteen published trials and 57 active clinical trials were included for review. CONCLUSIONS: Published and ongoing U.S. and international clinical trials for CRS and HIPEC are defining important parameters that include improving patient selection, strategic sequences of treatment, cytoreductive strategies, chemotherapeutics, optimal hyperthermic temperature and timing, and toxicity profiles. Main barriers or limitations to trial development remain patient enrollment, trial design, and oncologic community collaboration. Overall progress is positive with increasing number of clinical trials throughout the world. Collaboration between surgeons and the wider oncologic community will be crucial to validate this important treatment strategy.

Reconstruction options following pancreaticoduodenectomy after Roux-en-Y gastric bypass: a systematic review.

BACKGROUND: Obesity is a risk factor for pancreatic cancer which may be treated with Roux-en-Y gastric bypass and represents an increasing morbidity. Post-RYGB anatomy poses considerable challenges for reconstruction after pancreaticoduodenectomy (PD), a growing problem encountered by surgeons. We characterize specific strategies used for post-PD reconstruction in the RYGB patient. METHODS: PubMed search was performed using MeSH terms "Gastric Bypass" and "Pancreaticoduodenectomy" between 2000 and 2018. Articles reporting cases of pancreaticoduodenectomy in post-RYGB patients were included and systematically reviewed for this study. RESULTS: Three case reports and five case series (25 patients) addressed PD after RYGB; we report one additional case. The typical post-gastric bypass PD patient is a woman in the sixth decade of life, presenting most commonly with pain (69.2%) and/or jaundice (53.8%), median 5 years after RYGB. Five post-PD reconstructive options are reported. Among these, the gastric remnant was resected in 18 cases (69.2%), with reconstruction of biliopancreatic drainage most commonly achieved using the distal jejunal segment of the pre-existing biliopancreatic limb (73.1%). Similarly, in the eight cases where the gastric remnant was spared (30.8%), drainage was most commonly performed using the distal jejunal segment of the biliopancreatic limb (50%). Among the 17 cases reporting follow-up data, median was 27 months. CONCLUSION: Reconstruction options after PD in the post-RYGB patient focus on resection or preservation gastric remnant, as well as creation of new biliopancreatic limb. Insufficient data exists to make recommendations regarding the optimal reconstruction option, yet surgeons must prepare for the possible clinical challenge. PD reconstruction post-RYGB requires evaluation through prospective studies.

Molecular Targeting of H/MDM-2 Oncoprotein in Human Colon Cancer Cells and Stem-like Colonic Epithelial-derived Progenitor Cells.

BACKGROUND/AIM: We have tested whether the anticancer peptide, PNC-27, that kills cancer cells but not normal cells by binding to cancer cell membrane HDM-2 forming pores, kills CD44+ colon cancer stem cells. MATERIALS AND METHODS: Flow cytometry determined the CD44 and HDM-2 expression on six-colon cancer cell lines and one normal cell line (CCD-18Co). MTT, LDH release, annexin V binding and caspase 3 assays were used to assess PNC-27-induced cell death. Bioluminescence imaging measured PNC-27 effects on in vivo tumor growth. RESULTS: High percentages of cells in all six tumor lines expressed CD44. PNC-27 co-localized with membrane HDM-2 only in the cancer cells and caused total cell death (tumor cell necrosis, high LDH release, negative annexin V and caspase 3). In vivo, PNC-27 caused necrosis of tumor nodules but not of normal tissue. CONCLUSION: PNC-27 selectively kills colon cancer stem cells by binding of this peptide to membrane H/MDM-2.

Targeting Membrane HDM-2 by PNC-27 Induces Necrosis in Leukemia Cells But Not in Normal Hematopoietic Cells.

BACKGROUND/AIM: Anticancer peptide PNC-27 binds to HDM-2 protein on cancer cell membranes inducing the formation of cytotoxic transmembrane pores. Herein, we investigated HDM-2 membrane expression and the effect of PNC-27 treatment on human non-stem cell acute myelogenous leukemia cell lines: U937, acute monocytic leukemia; OCI-AML3, acute myelomonocytic leukemia and HL60, acute promyelocytic leukemia. MATERIALS AND METHODS: We measured cell surface membrane expression of HDM-2 using flow cytometry. Cell viability was assessed using MTT assay while direct cytotoxicity was measured by lactate dehydrogenase (LDH) release and induction of apoptotic markers annexin V and caspase-3. RESULTS: HDM-2 is expressed at high levels in membranes of U937, OCI-AML3 and HL-60 cells. PNC-27 can bind to membrane HDM-2 to induce cell necrosis and LDH release within 4 h. CONCLUSION: Targeting membrane HDM-2 can be a potential strategy to treat leukemia. PNC-27 targeting membrane HDM-2 demonstrated significant anti-leukemia activity in a variety of leukemic cell lines.

Anti-Cancer Tumor Cell Necrosis of Epithelial Ovarian Cancer Cell Lines Depends on High Expression of HDM-2 Protein in Their Membranes.

OBJECTIVE: Patients with epithelial ovarian cancers experience the highest fatality rates among all gynecological malignancies which require development of novel treatment strategies. Tumor cell necrosis was previously reported in a number of cancer cell lines following treatment with a p53-derived anti-cancer peptide called PNC-27. This peptide induces necrosis by transmembrane pore formation with HDM-2 protein that is expressed in the cancer cell membrane. We aimed to extend these studies further by investigating expression of membrane HDM-2 protein in ovarian cancer as it relates to susceptibility to PNC-27. PROCEDURES: Herein, we measured HDM-2 membrane expression in two ovarian cancer cell lines (SKOV-3 and OVCAR-3) and a non-transformed control cell line (HUVEC) by flow cytometric and western blot analysis. Immunofluorescence was used to visualize colocalization of PNC-27 with membrane HDM-2. Treatment effects with PNC-27 and control peptide were assessed using a MTT cell proliferation assay while direct cytotoxicity was measured by lactate dehydrogenase (LDH) release and induction of apoptotic markers; annexin V and caspase-3. RESULTS: HDM-2 protein was highly expressed and frequently detected in the membranes of SKOV-3 and OVCAR-3 cells; a prominent 47.6 kDa HDM-2 plasma membrane isoform was present in both cell lines whereas 25, 29, and 30 kDa isoforms were preferentially expressed in OVCAR-3. Notably, PNC-27 colocalized with HDM-2 in the membranes of both cancer cell lines that resulted in rapid cellular necrosis. In contrast, no PNC-27 colocalization and cytotoxicity was observed with non-transformed HUVEC demonstrating minimal expression of membrane HDM-2. CONCLUSIONS: Our results suggest that HDM-2 is highly expressed in the membranes of these ovarian cancer cell lines and colocalizes with PNC-27. We therefore conclude that the association of PNC-27 with preferentially expressed membrane HDM-2 isoforms results in the proposed model for the formation of transmembrane pores and epithelial ovarian cancer tumor cell necrosis, as previously described in a number of solid tissue and hematologic malignancies.

Erratum: Thadi A.; et al. Early Investigations and Recent Advances in Intraperitoneal Immunotherapy for Peritoneal Metastasis. Vaccines 2018, 6, 54.

The authors wish to make the following corrections to this paper [...].

Pancreaticoduodenectomy outcomes for locally advanced right colon cancers: A systematic review.

BACKGROUND: Pancreaticoduodenectomy (PD) with right hemicolectomy (RH) to treat locally advanced right colon cancer (LARCC) has been rarely reported in the literature. Herein, we characterize clinicopathologic factors and evaluate outcomes of en bloc PD and RH for LARCC. METHODS: A systematic review of the literature was conducted on PubMed using MeSH terms ("pancreaticoduodenectomy" or "pancreas/surgery" or "duodenum/surgery" or "colectomy") and ("colonic neoplasms"). Data was extracted from patients who underwent en bloc PD and RH for LARCC. Factors investigated included patient demographics, surgical and pathologic parameters, postoperative complications, disease recurrence, and survival. RESULTS: Our search yielded 27 articles (106 patients), including 1 case from our institution. Most patients were male (62.1%), median age 58 years (range 34-83). Surgical procedures performed included en bloc RH with PD (n = 91, 85.8%) and en bloc RH with pylorus-preserving PD (n = 15, 14.2%). Among reported, 95.5% of patients (n = 63), underwent R0 resection. One or more complications were reported in 33 patients (52.4%). Median survival was 168 months. Survival after resection was 75.9% at 2 years and 66.3% at 5 years. Overall survival was greater in patients with no lymph node involvement (IIC versus IIIC, hazard ratio 8.4, P = .003). Five-year survival for patients was 84.9% in patients with stage IIC versus 46.4% in patients with stage IIIC. There were 3 postoperative mortalities. CONCLUSION: This data demonstrates that en bloc PD and RH is rarely performed yet can be a potentially safe treatment option in patients with LARCC. Lymph node involvement was the only independent prognostic factor.

Early Investigations and Recent Advances in Intraperitoneal Immunotherapy for Peritoneal Metastasis.

Peritoneal metastasis (PM) is an advanced stage malignancy largely refractory to modern therapy. Intraperitoneal (IP) immunotherapy offers a novel approach for the control of regional disease of the peritoneal cavity by breaking immune tolerance. These strategies include heightening T-cell response and vaccine induction of anti-cancer memory against tumor-associated antigens. Early investigations with chimeric antigen receptor T cells (CAR-T cells), vaccine-based therapies, dendritic cells (DCs) in combination with pro-inflammatory cytokines and natural killer cells (NKs), adoptive cell transfer, and immune checkpoint inhibitors represent significant advances in the treatment of PM. IP delivery of CAR-T cells has shown demonstrable suppression of tumors expressing carcinoembryonic antigen. This response was enhanced when IP injected CAR-T cells were combined with anti-PD-L1 or anti-Gr1. Similarly, CAR-T cells against folate receptor α expressing tumors improved T-cell tumor localization and survival when combined with CD137 co-stimulatory signaling. Moreover, IP immunotherapy with catumaxomab, a trifunctional antibody approved in Europe, targets epithelial cell adhesion molecule (EpCAM) and has shown considerable promise with control of malignant ascites. Herein, we discuss immunologic approaches under investigation for treatment of PM.