RUNX3 Controls a Metastatic Switch in Pancreatic Ductal Adenocarcinoma.

For the majority of patients with pancreas cancer, the high metastatic proclivity is life limiting. Some patients, however, present with and succumb to locally destructive disease. A molecular understanding of these distinct disease manifestations can critically inform patient management. Using genetically engineered mouse models, we show that heterozygous mutation of Dpc4/Smad4 attenuates the metastatic potential of Kras(G12D/+);Trp53(R172H/+) pancreatic ductal adenocarcinomas while increasing their proliferation. Subsequent loss of heterozygosity of Dpc4 restores metastatic competency while further unleashing proliferation, creating a highly lethal combination. Expression levels of Runx3 respond to and combine with Dpc4 status to coordinately regulate the balance between cancer cell division and dissemination. Thus, Runx3 serves as both a tumor suppressor and promoter in slowing proliferation while orchestrating a metastatic program to stimulate cell migration, invasion, and secretion of proteins that favor distant colonization. These findings suggest a model to anticipate likely disease behaviors in patients and tailor treatment strategies accordingly.

Targeting the Gut Microbiome to Mitigate Immunotherapy-Induced Colitis in Cancer.

Immune checkpoint inhibitors (ICIs) have been a transformational advance in cancer therapy in the past decade. However, ICIs can produce immune-related adverse effects (irAEs), which can lead to both morbidity and premature termination of therapy. Recent studies suggest that the gut microbiota and its metabolites affect ICI efficacy and toxicity. Herein, we review such evidence in the context of ICI-induced colitis. In particular, the short-chain fatty acid butyrate, a microbial metabolite, has known protective effects on the intestine. We discuss how the use of dietary prebiotics, which can be metabolized by bacteria to produce butyrate, can be an intriguing new investigational approach to prevent ICI-associated colitis and lead to improved patient outcomes.

Phase I/II Trial of Combined Pegylated Liposomal Doxorubicin and Cyclophosphamide in Metastatic Breast Cancer.

INTRODUCTION: Doxorubicin in combination with cyclophosphamide is active in breast cancer; however, its use in metastatic cancer is limited owing to cardiotoxicity. Pegylated liposomal doxorubicin (PLD) was formulated to decrease the toxicity of conventional doxorubicin. We evaluated the safety and efficacy of PLD with metronomic oral cyclophosphamide. PATIENTS AND METHODS: We conducted a single-arm open-label phase I/II study of PLD and oral cyclophosphamide in patients with metastatic breast cancer. In phase I, 3 escalating doses of PLD were planned (30, 35, and 40 mg/m2) with cyclophosphamide (60 mg/m2 orally daily) to determine the maximum tolerated dose (MTD). In phase II, the MTD of PLD in combination of oral cyclophosphamide was used to assess the primary endpoint of overall clinical response rate and secondary endpoints of progression-free survival, overall survival, and adverse events. RESULTS: Thirty patients were enrolled in the study (n = 6 in phase I and n = 24 in phase II). The MTD of PLD from phase I was 30 mg/m2. The median progression-free and overall survival for the entire cohort were 6.4 months (95% confidence interval, 3.9 months to N/A) and 18.7 months (95% confidence interval, 15.1-31.5 months), respectively. A total of 21 (75%) patients had clinical benefit, including 6 (21%) patients with partial response and 15 (54%) patients with stable disease. The majority of toxicities were uncomplicated myelosuppression, and no infection or febrile neutropenia were noted in any patient. CONCLUSION: PLD in combination with daily oral cyclophosphamide is an active and tolerable regimen in metastatic breast cancer.

Analysis of clinical prognostic factors for adult patients with head and neck sarcomas.

OBJECTIVE: To evaluate the treatment, outcome, and prognostic factors in patients with head and neck sarcomas treated in an academic medical center. STUDY DESIGN: Case series. SETTING: Academic medical center. SUBJECTS AND METHODS: We performed a retrospective analysis of adult patients (n = 97) with primary head and neck sarcomas treated between 2000 and 2012. We analyzed the treatment, outcome, and potential factors predictive of disease-free survival and disease-specific survival. We also evaluated the outcome and prognostic factors in patients with bone and soft tissue sarcomas. RESULTS: The median overall survival was 6.8 years, with 2-year and 5-year overall survival rates of 78% (95% confidence interval [CI], 66%-86%) and 59% (95% CI, 44%-72%), respectively. Univariable analysis revealed that age at diagnosis (>60 years: hazard ratio [HR], 2.7; 95% CI, 1.2-6.2; P = .01), surgical intervention (HR, 8.3; 95% CI, 3.5-19.5; P < .001), and metastatic disease (HR, 4.3; 95% CI, 1.3-13.6; P = .01) were significantly associated with disease-specific survival. CONCLUSION: In this study, patients over the age of 60 years at diagnosis and those with inoperable disease at initial presentation had significantly worse disease-specific survival. Surgical intervention remains the optimal treatment modality for those with resectable disease and was associated with significantly better survival in this heterogeneous series. Further multi-institutional studies are required to better define prognostic factors in individual histological subtypes.

Multiple liver abscess formation and primary gastrointestinal stromal tumor.

Gastrointestinal stromal tumors are the most common mesenchymal tumors of the gastrointestinal tract. The introduction of a number of small molecule tyrosine kinase inhibitors has revolutionized the management of metastatic disease. Surgery is the mainstay of management for localized disease. Patients with high risk tumors are treated with adjuvant imatinib. We report the rare presentation of a localized primary small bowel gastrointestinal stromal tumor in association with multiple liver abscesses. Cystic liver lesions should be fully evaluated in gastro intestinal tumor patients to exclude an infective cause. Treatment with intravenous antibiotics resulted in clinical and radiological improvement of the liver abscesses. The small bowel tumor was treated with surgical resection.

Enzymatic targeting of the stroma ablates physical barriers to treatment of pancreatic ductal adenocarcinoma.

Pancreatic ductal adenocarcinomas (PDAs) are characterized by a robust fibroinflammatory response. We show here that this desmoplastic reaction generates inordinately high interstitial fluid pressures (IFPs), exceeding those previously measured or theorized for solid tumors, and induces vascular collapse, while presenting substantial barriers to perfusion, diffusion, and convection of small molecule therapeutics. We identify hyaluronan, or hyaluronic acid (HA), as the primary matrix determinant of these barriers and show that systemic administration of an enzymatic agent can ablate stromal HA from autochthonous murine PDA, normalize IFP, and re-expand the microvasculature. In combination with the standard chemotherapeutic, gemcitabine, the treatment permanently remodels the tumor microenvironment and consistently achieves objective tumor responses, resulting in a near doubling of overall survival.