Intraoral Gavage of Second-Generation Probiotic Lactobacillus Reuteri Releasing IFN-β (LR-IFN-β) Mitigates Intestinal Irradiation Toxicity and Improves Survival During Whole Abdomen Irradiation (WAI)

PURPOSE/OBJECTIVE(S)

We sought to establish a method by which to overcome the toxicity of WAI to facilitate clinical application in Ovarian Cancer patients.

MATERIALS/METHODS

We irradiated C57BL/6J mice to 19.75 Gy WAI and assessed the primary endpoint of overall survival (OS). In a separate experiment, mice were irradiated to 12 Gy WAI and intestinal barrier integrity was compared between groups: control (0 Gy), irradiation only, 12 Gy + LR, 12 Gy + IFN-β, and 12 Gy + LR-IFN-β. Luminex assay of plasma and intestinal cells were also assayed at day 5 after WAI for radiation-induced inflammatory cytokines, and fecal matter was analyzed for LR-IFN-β clearance and levels of the LR-derived IFN-β gene from day 1 to 5 in control non-irradiated mice. Moreover, fluorescent beads were intraorally administered three hours prior to sacrifice at days 2 or 5 after WAI, and blood was assayed for beads.

RESULTS

Mice receiving LR-IFN-β (109 bacteria in 100 mL of saline) 24-hours following a single fraction of 19.75 Gy WAI showed improved OS compared to control irradiated mice (p = 0.03). LR-IFN-β gavage maintained intestinal barrier integrity (p < 0.05) by stimulating intestinal stem cells regenerations (improved levels of Lgr5+ cells, occludin, and I-CAM; p < 0.05), and reduced levels of intestinal pro-inflammatory cytokines, including IFN-γ (p = 0.0261), IL-3 (p < 0.0020) and IL-17 (p < 0.0070). There was no significant effect of control LR or intraperitoneal injection of IFN-β protein at 24 hours after WAI. Detectable levels of LR-IFN-β bacteria were also cleared from fecal matter by day three via colony assay and rt-PCR, with no detectable growth of LR-IFN-β in blood from gavaged irradiated mice (13.5 Gy WAI).

CONCLUSION

LR-IFN-β is both a feasible and effective radiation mitigator that could potentially improve the management of ovarian cancer patients. Furthermore, the subsequent addition of platinum/taxane-based chemotherapy to the combination of WAI and LR-IFN-β should reduce tumor volume while protecting the intestine and thus improve overall survival in ovarian cancer patients.

Impact of Race and Socioeconomic Factors on Clinical Outcomes in Cervical and Endometrial Cancer Patients Treated with Brachytherapy

PURPOSE/OBJECTIVE(S)

Racial and socioeconomic disparities impact cancer care and outcomes. This project aimed to evaluate relationship between race and socioeconomic factors and clinical outcomes in patients with cervical and endometrial cancer.

MATERIALS/METHODS

All cervical and endometrial cancer patients treated with brachytherapy at our institution from 2007-2017 were identified. Race, insurance status, employment status, disability status, and distance from brachytherapy center were recorded. Clinical characteristics including stage at presentation, number of involved nodes, histology, and brachytherapy technique (cervical cancer only) were recorded. PFS and OS were calculated from date of last brachytherapy fraction, with censorship at date of last follow-up. Correlation was tested between race and socioeconomic factors and PFS and OS using Cox regression models. Association with other outcomes was examined with Wilcoxon rank sum tests, Fisher's exact tests, and Spearman's rank correlation coefficients.

RESULTS

A total of 251 cervical and 130 endometrial cancer patients were identified, with median follow-up 5.2 years and 4.8 years, respectively. For cervical cancer, UVA showed significant correlation for PFS and OS with race, insurance status, employment status, and disability status. For endometrial cancer, UVA showed significant correlation for PFS with race, insurance status, and disability status, and for OS with race and insurance status. For cervical cancer, MVA showed significantly improved PFS in patients with insurance (p < 0.001) and patients who were employed (p = 0.002), and significantly improved OS in patients who were white (p = 0.039), patients with insurance (p<0.001), and patients who were employed (p-0.001). For endometrial cancer, MVA showed significantly improved PFS and OS in patients who were white (p = 0.003 and p = 0.005, respectively) and patients with insurance (p = 0.027 and p = 0.002, respectively). For cervical cancer, there was no correlation between insurance or employment status and stage. For endometrial cancer, there was no correlation between race or insurance status and stage.

CONCLUSION

For cervical cancer, insurance and employment status are significant predictors of PFS and OS, and race is additionally a significant predictor of OS. For endometrial cancer, race and insurance status are significant predictors of PFS and OS.

The role of adjuvant treatment for early-stage uterine clear cell carcinomas

BACKGROUND

Uterine clear cell carcinoma is a rare and aggressive subtype of endometrial carcinoma. Prospective clinical trials have not been feasible for this rare tumor, and data regarding the optimal adjuvant treatment regimen for early-stage uterine clear cell carcinomas is limited. Our study's objective was to determine if adjuvant chemotherapy or radiation therapy improves patients' outcomes in stage I and II uterine clear cell carcinoma.

METHODS

Patients with stage I and II uterine clear cell carcinoma were identified at a single institution. All cases were reviewed by a gynecologic pathologist. Both pure and mixed non-serous uterine clear cell carcinomas were included. Primary outcomes were recurrence free survival and overall survival.

RESULTS

A total of 71 patients were identified including 39 (55%) pure and 32 (45%) mixed clear cell carcinoma. Most patients were FIGO stage IA (77.5%). Most patients (n = 58, 82%) received adjuvant therapy, including 43 (61%) receiving chemotherapy, 50 (70%) receiving radiation therapy, and 35 (49%) receiving both. Recurrence free survival was not significantly different among patients receiving no or <6 cycles of chemotherapy versus patients receiving 6 cycles of chemotherapy (p = 0.39). However, median OS was significantly different among patients receiving no or <6 cycles of chemotherapy versus 6 cycles of chemotherapy (p = 0.004). On univariable analysis, 6 cycles of chemotherapy was significantly associated with improved OS (HR 0.1, 95% CI 0.01-0.07). Presence of LVSI, mutated p53, number of pelvic and para-aortic lymph nodes assessed, adjuvant chemotherapy (any number of cycles), and >2 medical co-morbidities were not significant predictors of OS on univariable analysis. On multivariable analysis, 6 cycles of adjuvant chemotherapy remained a significant predictor of improved OS (HR 0.1, 95% CI 0.01-0.8).

CONCLUSIONS

In this study, administration of 6 cycles of chemotherapy appears to significantly improve OS. This finding suggests consideration of 6 cycles of adjuvant chemotherapy in patients with early-stage uterine clear cell carcinoma, however clinical trials are needed to confirm these findings.

Inhibition of d-Ala incorporation into wall teichoic acid in Staphylococcus aureus by desleucyl-oritavancin

The mode of action for desleucyl-oritavancin was investigated by adding an antibiotic to Staphylococcus aureus during its growth in a defined medium containing l,d-[1-15N]Ala and l-[1-13C]Lys, or d-[1-15N]Ala. 13C{15N} and 15N{13C} rotational-echo double resonance NMR determined that desleucyl-oritavancin inhibited the incorporation of d-[1-15N]Ala into wall teichoic acid.

Evaluation of dentin abrasion during professional tooth cleaning in an in vitro model

OBJECTIVES

Professional tooth cleaning (PTC) may lead to loss of exposed dentin. The aim of the present study was to determine the absolute loss of dentin during PTC using various product combinations with an in vitro model.

MATERIAL AND METHODS

Dentin specimens (72) were randomly assigned to nine groups. In four groups each, prophy brushes and prophy cups were used in combination with four different abrasives (calcium pyrophosphate, pumice, Hawe cleanic, Nupro coarse). In the ninth group, a rubber cup with embedded fluoride and abrasives was used (pasteless prophy cup). The treatment time was 37 s. Surface loss was determined by profilometry.

RESULTS

The surface loss in the nine groups was as following: (1) brush/calcium pyrophosphate: 6.18 microm (a); (2) brush/pumice: 5.51 microm; (3) brush/Nupro coarse: 10.10 microm (b); (4) brush/Hawe cleanic: 1.88 (a, b); (5) prophy cup/calcium pyrophosphate 2.07 (c); (6) prophy cup/pumice: 6.07 microm; (7) prophy cup/Nupro coarse: 5.93 microm (c); (8) prophy cup/Hawe cleanic: 4.93 microm (c); (9) pasteless prophy cup: 11.86 microm (c). Groups with the same letter in parentheses are statistically significant different at p<0.05. In a pooled analysis, no statistically significant difference between brushes and prophy cups was found.

CONCLUSION

In the present study, the surface loss of about eight PTC procedures was simulated. Hence, the dentin loss ranged between 0.24 and 1.48 microm per PTC. Therefore, PTC does not seem to be a main factor in dentin loss.

Interspecies differences in systemic drug availability following subcutaneous pulsatile administration in cattle, sheep, dogs, and rats

Rats, dogs, sheep, and cattle were implanted subcutaneously with stainless-steel tissue cages. Bolus injections of cefoxitin and ivermectin were administered to the interiors of the tissue cages 11, 32, and 60 days after implantation to simulate pulsatile drug release from an implanted device. Plasma drug levels were determined for 6 h for cefoxitin and up to 8 days for ivermectin. Tissue cages were retrieved 3 and 6 months after implantation for macroscopic and microscopic examination. In dogs and rats, plasma levels of both drugs following administrations to the tissue cages were significantly lower than those following subcutaneous injection, suggesting that the tissue growth around and in the cages posed a barrier to systemic drug availability in those species. In cattle and sheep, the tissue cages and associated tissue did not inhibit systemic availability of either drug as compared with routine subcutaneous administration.