Models in Pancreatic Neuroendocrine Neoplasms: Current Perspectives and Future Directions.

Pancreatic neuroendocrine neoplasms (pNENs) are a heterogeneous group of tumors derived from multiple neuroendocrine origin cell subtypes. Incidence rates for pNENs have steadily risen over the last decade, and outcomes continue to vary widely due to inability to properly screen. These tumors encompass a wide range of functional and non-functional subtypes, with their rarity and slow growth making therapeutic development difficult as most clinically used therapeutics are derived from retrospective analyses. Improved molecular understanding of these cancers has increased our knowledge of the tumor biology for pNENs. Despite these advances in our understanding of pNENs, there remains a dearth of models for further investigation. In this review, we will cover the current field of pNEN models, which include established cell lines, animal models such as mice and zebrafish, and three-dimensional (3D) cell models, and compare their uses in modeling various disease aspects. While no study model is a complete representation of pNEN biology, each has advantages which allow for new scientific understanding of these rare tumors. Future efforts and advancements in technology will continue to create new options in modeling these cancers.

Pivotal Role of Genetic Counselors in the Uptake of Germline Genetic Testing in Non-Metastatic Breast Cancer and the Impact of Testing on Surgical Decision Making.

BACKGROUND: Genetic testing is increasingly utilized in breast cancer patients; however, testing rates remain low. We aimed to evaluate the rate of genetic testing at a tertiary academic medical center utilizing a multidisciplinary clinic model including genetic counselor. METHODS: A single-center retrospective chart review was performed on a cohort of newly diagnosed breast cancer patients from January 2018 through February 2019. Patients were reviewed for genetic screening eligibility, consultation with a genetic counselor, and test results. RESULTS: Final analysis included 426 patients. 261 (61.3%) were found to meet National Comprehensive Cancer Network guidelines for genetic testing, of which 178 patient (68.2%) underwent testing and 32 patients (12.3%) declined testing. Of the 165 not eligible for testing, 5 patients were tested. A total of 183 patients underwent testing and 116 (63.4%) had a negative result, 17 (9.3%) were positive for at least one gene mutation and 50 (27.3%) were identified to have a variant of unknown significance (VUS). There was a positive association between those patients who met with a genetic counselor and eligibility for testing (OR 31.1, 95% CI 16.0-60.5). CONCLUSIONS: Genetic testing result has become an increasingly important factor when defining optimal surgical treatment for breast cancer patients. Increasing the availability of genetic consultation for breast cancer patients can improve testing rates and patient selection.

Persistent opioid use after curative-intent hepatectomy for neoplastic disease.

BACKGROUND AND OBJECTIVES: This study analyzed persistent opioid use in opioid-naïve and nonopioid-naïve patients undergoing hepatectomy for neoplastic disease. METHODS: A retrospective review was performed of a prospective database using inclusion criteria of hepatectomy for neoplastic disease from October 2013 to December 2017. Prescription data were collected from the North Carolina Controlled Substance Reporting System. Persistent opioid use was defined as patients who continued filling opioid prescriptions 90 days to 1 year after surgery. Patients who did not receive opioid prescriptions between 12 months and 31 days before surgery were defined as naïve. RESULTS: The analysis included 75 surgeries on naïve and 58 surgeries on nonnaïve patients. 56% of naïve patients and 79% of nonnaïve patients developed persistent opioid use, respectively (p = .0056). Naïve patients received 2.24 ± 4.30 MMEs/day, while nonnaïve patients received 5.50 ± 5.98 MMEs/day during Postoperative days 90-360 (95% CI, 1.41-5.10; p < .001). Naïve patients with a lower Preoperative ECOG score were more likely to develop persistent opioid use (OR, 0.45; 95% CI, 0.21-0.99; p = .048). CONCLUSION: More than half of naïve patients undergoing hepatectomy developed persistent opioid use within the first year, though significantly less than nonnaïve patients. Improved performance status was associated with an increased risk of persistent opioid use in naïve patients.

Diffusion and Binding of Mismatch Repair Protein, MSH2, in Breast Cancer Cells at Different Stages of Neoplastic Transformation.

The interior of cells is a highly complex medium, containing numerous organelles, a matrix of different fibers and a viscous, aqueous fluid of proteins and small molecules. The interior of cells is also a highly dynamic medium, in which many components move, either by active transport or passive diffusion. The mobility and localization of proteins inside cells can provide important insights into protein function and also general cellular properties, such as viscosity. Neoplastic transformation affects numerous cellular properties, and our goal was to investigate the diffusional and binding behavior of the important mismatch repair (MMR) protein MSH2 in live human cells at various stages of neoplastic transformation. Toward this end, noncancerous, immortal, tumorigenic, and metastatic mammary epithelial cells were transfected with EGFP and EGFP-tagged MSH2. MSH2 forms two MMR proteins (MutSα and MutSß) and we assume MSH2 is in the complex MutSα, though our results are similar in either case. Unlike the MutS complexes that bind to nuclear DNA, EGFP diffuses freely. EGFP and MutSα-EGFP diffusion coefficients were determined in the cytoplasm and nucleus of each cell type using fluorescence recovery after photobleaching. Diffusion coefficients were 14-24 µm2/s for EGFP and 3-7 µm2/s for MutSα-EGFP. EGFP diffusion increased in going from noncancerous to immortal cells, indicating a decrease in viscosity, with smaller changes in subsequent stages. MutSα produces an effective diffusion coefficient that, coupled with the free EGFP diffusion measurements, can be used to extract a pure diffusion coefficient and a pseudo-equilibrium constant K*. The MutSα nuclear K* increased sixfold in the first stage of cancer and then decreased in the more advanced stages. The ratio of nuclear to cytoplasmic K*for MutSα increased almost two orders of magnitude in going from noncancerous to immortal cells, suggesting that this quantity may be a sensitive metric for recognizing the onset of cancer.