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NK cell tumor infiltration is associated with good prognosis in patients with metastatic castration-resistant prostate cancer (mCRPC). NK cells recognize and kill targets by a process called natural cytotoxicity. We hypothesized that promoting an antigen-specific synapse with coactivation may enhance NK cell function in mCRPC. We describe a tri-specific killer engager (TriKE) construct that engages with the activating receptor CD16 on NK cells and prostate-specific membrane antigen (PSMA) on mCRPC cells and has an IL15 moiety that is essential for NK cell survival, proliferation, and priming. We show that the PSMA TriKE specifically binds to PSMA-expressing cells and significantly enhances expansion, degranulation, and cytokine production of NK cells derived from healthy donors or patients with prostate cancer. Bystander killing of PSMA-negative tumor cells was also achieved with PSMA TriKE treatment when cocultured with PSMA-positive cells, suggesting potential PSMA TriKE benefit in controlling tumor antigen escape. When tested under physiologic conditions recapitulating the mCRPC tumor microenvironment, NK cells treated with PSMA TriKE and prolonged exposure to hypoxia or myeloid-derived suppressor cells maintained their potent function whereas IL15-treated NK cells showed greatly impaired cytotoxicity. Finally, in vivo testing of PSMA TriKE showed improved tumor control and survival of mice as compared with IL15-treated and untreated control groups. In conclusion, PSMA TriKE demonstrates potential as a new therapy for advanced prostate cancer by providing additional signals to NK cells to maximize their antitumor potential in prostate cancer, especially in the setting of a hostile tumor microenvironment., (©2024 American Association for Cancer Research.)

Background: Natural killer (NK) cells are non-antigen specific innate immune cells that can be redirected to targets of interest using multiple strategies, although none are currently FDA-approved. We sought to evaluate NK cell infiltration into tumors to develop an improved understanding of which histologies may be most amenable to NK cell-based therapies currently in the developmental pipeline., Methods: DNA (targeted/whole-exome) and RNA (whole-transcriptome) sequencing was performed from tumors from 45 cancer types (N = 90,916 for all cancers and N = 3365 for prostate cancer) submitted to Caris Life Sciences. NK cell fractions and immune deconvolution were inferred from RNA-seq data using quanTIseq. Real-world overall survival (OS) and treatment status was determined and Kaplan-Meier estimates were calculated. Statistical significance was determined using X 2 and Mann-Whitney U tests, with corrections for multiple comparisons where appropriate., Results: In both a pan-tumor and prostate cancer (PCa) -specific setting, we demonstrated that NK cells represent a substantial proportion of the total cellular infiltrate (median range 2-9% for all tumors). Higher NK cell infiltration was associated with improved OS in 28 of 45 cancer types, including (PCa). NK cell infiltration was negatively correlated with common driver mutations and androgen receptor variants (AR-V7) in primary prostate biopsies, while positively correlated with negative immune regulators. Higher levels of NK cell infiltration were associated with patterns consistent with a compensatory anti-inflammatory response., Conclusions: Using the largest available dataset to date, we demonstrated that NK cells infiltrate a broad range of tumors, including both primary and metastatic PCa. NK cell infiltration is associated with improved PCa patient outcomes. This study demonstrates that NK cells are capable of trafficking to both primary and metastatic PCa and are a viable option for immunotherapy approaches moving forward. Future development of strategies to enhance tumor-infiltrating NK cell-mediated cytolytic activity and activation while limiting inhibitory pathways will be key., (© 2024. The Author(s).)

Background/aims: Recruitment is often a barrier in clinical trials that include minoritized populations, such as individuals with sickle cell disease. In the United States, the majority of people with sickle cell disease identify as Black or African American. In sickle cell disease, 57% of the United States trials that ended early did so due to low enrollment. Thus, there is a need for interventions that improve trial enrollment in this population. After lower-than-expected recruitment during the first 6 months of the Engaging Parents of Children with Sickle Cell Anemia and their Providers in Shared-Decision-Making for Hydroxyurea trial, a multi-site study for young children with sickle cell disease, we collected data to understand barriers and used the Consolidated Framework for Implementation Research to categorize them and guide the development of targeted strategies., Methods: Study staff used screening logs and coordinator and principal investigator calls to identify recruitment barriers that were then mapped onto Consolidated Framework for Implementation Research constructs. Targeted strategies were implemented during Months 7-13. Recruitment and enrollment data were summarized before (Months 1-6) and during the implementation period (Months 7-13)., Results: During the first 13 months, 60 caregivers ( M  = 30.65 years; SD  = 6.35) enrolled in the trial. Most caregivers primarily self-identified as female ( n  = 54, 95%) and African American or Black ( n  = 51, 90%). Recruitment barriers mapped onto three Consolidated Framework for Implementation Research constructs: (1) Process barriers (i.e. no identified "site champion" and poor recruitment planning at several sites); (2) Inner setting barriers (i.e. limited communication, low relative study priority at several sites); and (3) Outer setting barriers (i.e. poor patient attendance at clinic appointments). Targeted strategies to improve recruitment included (1) principal investigator site visits and retraining on recruitment procedures to address process barriers; (2) increased frequency of communication through all coordinator, site principal investigator, and individual site calls to address inner setting barriers; and (3) development and implementation of no-show procedures for clinic appointments to address outer setting barriers. After implementation of the recruitment strategies, the number of caregivers identified for pre-screening increased from 54 to 164, and enrollment more than tripled from 14 to 46 caregiver participants., Conclusion: Consolidated Framework for Implementation Research constructs guided the development of targeted strategies that increased enrollment. This reflective process reframes recruitment challenges as the responsibility of the research team rather than characterizing minoritized populations as "difficult" or "hard to reach." Future trials including patients with sickle cell disease and minoritized populations may benefit from this approach.

Differences in the physiology and biological susceptibilities of adults and infants have led to growing interest in safety evaluation methods for exposures from infant formula packaging. In addition to potential physiological differences, infants aged 0-6 months may consume a sole source of food, infant formula or breast milk, and consume higher amounts of food relative to body weight compared to adults. While the duration of the exposure is short compared to the expected lifespan of the individual, it occurs during a period of important developmental processes. The purpose of this document is to (1) review key biological and exposure elements that may impact the evaluation of safety for food contact products intended for use by infants, (2) summarize the current reproductive and developmental toxicity testing protocols available, and (3) identify potential data gaps concerning this period of development., (Published by Elsevier Ltd.)

In the United States, the Food and Drug Administration (FDA) is the agency responsible for ensuring that the direct food additives and color additives used in food are safe for all consumers. In order to determine the safety of these additives for consumption, appropriate information and results from a series of tests must be made available to the agency. In 1982, in an effort to provide guidance to the food industry concerning the appropriate tests for the determination of safety, the FDA issued the Toxicological Principles for the Safety Assessment of Direct Food Additives and Color Additives Used in Foods, commonly referred to as the Redbook. In 1993, based on the expansion of technology and the use of food additives, as well as the refinement of the scientific criteria for establishing safety, the FDA updated its guidelines and issued the draft Redbook II. Since Redbook II was issued, additional refinements have been made in the procedures for the multigeneration reproduction study and for the assessment of effects on male reproduction. The latest proposed guidelines for multigeneration studies are provided here.

The Food and Drug Administration (FDA) is the agency responsible for ensuring that the direct food additives and color additives used in food in the United States are safe for all consumers. In 1982, in an effort to provide guidance concerning appropriate tests, the FDA issued Toxicological Principles for the Safety Assessment of Direct Food Additives and Color Additives Used in Food, commonly known as the Redbook. The Redbook included detailed guidelines for testing the effects of direct and indirect food and color additives on mothers and their developing fetuses. Based on refinements in safety assessment and risk evaluation as well as expansion of knowledge concerning the metabolism and pharmacokinetics of food and color additives, the need to revise and update the 1982 document became apparent. In 1993, Redbook II in draft form was made available for public comment. Since then, test end points and developmental landmarks have been refined. The latest proposed guidelines for developmental toxicity studies are provided here.

While research on spinal cord injury (SCI) is abundant, few studies focus on women. This population-based study investigates differences in the prevalence of secondary conditions between 128 women and 522 men. Case managers retrospectively interviewed 650 persons regarding medical and psychological conditions secondary to SCI, as well as other life issues. Overall, males and females show more similarities than differences in the ways in which they manage life with SCI. Differences were found, though, regarding etiology of initial injury, insurance coverage, caregiver use, transportation use, medication use, and in other medical and behavioral areas. Females are significantly involved in more automobile crashes than males, while males are involved in more galls than females. Females are more reliant on Medicaid, while males report more Medicare and Worker's Compensation coverage. Females are more likely to have a paid attendant as a caregiver while males are more likely to have their spouse or parents assist. Males report more independence in their use of transportation than females. Males and females also report significant differences in the use of medication. Females are more likely to use medication any time it is a treatment option. Males are more active, use tobacco more and have more arm fractures postinjury than females.

Fumonisin B1 (FB1) is one of a number of mycotoxins produced by fungi, especially Fusarium sp. As a contaminant of many maize-derived products, this toxin is associated with a variety of animal diseases, including esophageal cancer and possibly neural tube defects in humans. We have investigated the embryotoxic potential of this compound in New Zealand White rabbits. Animals were dosed by gavage daily on GD 3-19 with purified FB1 at 0.10, 0.50, or 1.00 mg/kg/day. Maternal lethality occurred at the 0.50 and 1.00 mg/kg/day doses. When examined on GD 29, there were no differences in maternal body weight, maternal weight gain, maternal organ weights, number of nonlive implantations, and number of malformations. Fetal weight was decreased at 0.50 and 1.00 mg/kg/day (13 and 16%, respectively); this was true for male and female pups. Fetal liver and kidney weights were also decreased at these doses. Analysis of embryonic sphinganine to sphingosine ratios demonstrated no differences between control and treated embryos on GD 20, although these ratios were increased in maternal urine, serum, and kidney when compared to control animals. These data suggest that FB1 did not cross the placenta and that the observed decreased fetal weight was probably the result of maternal toxicity, rather than any developmental toxicity produced by FB1.

The effect of maternal consumption of dietary ethanol and high doses of vitamin A by gavage was investigated by evaluating plasma, liver and foetal vitamin A in Osborne-Mendel pregnant rats with a view to assessing whether ethanol modulated the potential toxicity of excess vitamin A. All groups received 4000 IU vitamin A/litre in a liquid diet. Ethanol-exposed groups also received 6.4% (v/v) ethanol in the liquid diet. Vitamin A was administered by gavage once per day in corn oil in doses ranging from 10,000 to 160,000 IU/kg body weight. Plasma vitamin A levels in ethanol-exposed groups were similar to levels in a pair-fed group. Plasma vitamin A levels were similar in the group given ethanol plus 40,000 IU vitamin A/kg and the group given 40,000 IU vitamin A/kg only, but were higher in the group receiving ethanol plus 80,000 IU vitamin A/kg than in the group given 80,000 IU vitamin A/kg only. Retinyl esters were present in the plasma of animals receiving 160,000 IU vitamin A/kg only, indicating possible saturation of the liver with vitamin A. Retinyl palmitate levels in female foetuses of the group administered ethanol plus 80,000 IU vitamin A/kg were significantly higher than those of the group administered 80,000 IU vitamin A/kg only; no significant differences in levels of retinyl palmitate in male foetuses were observed between these two groups. This observation suggests a possible sex difference in the modulation of vitamin A toxicity by ethanol in the foetus.

The use of alkylating agents in treating cancer is limited by their toxicity to both normal and tumor tissue. Early in vitro studies indicated that zinc might be effective in mitigating this toxicity to normal tissue. The present studies were done to determine the capability of zinc to induce in vivo a protective response to an alkylating agent without also contributing to mortality. Tumor-free and L1210 leukemia-bearing female B6D2F1 mice were treated with zinc before administration of the alkylating agent nitrogen mustard. Protocols for administration route and frequency as well as the chemical formulation of the zinc were varied. The effect of a phytate-free diet was studied. Two parameters were used to determine the effectiveness of zinc in protecting animals from the toxicity of nitrogen mustard: the number of tumor-free mice that survived and an increase in the median life span of the tumor-bearing mice. The zinc-induction protocols used in these studies provided a limited degree of protection against nitrogen mustard toxicity in tumor-free female mice, but in tumor-bearing animals the protective response elicited with the protocols examined did not provide an appreciable therapeutic benefit.

Previous studies with cultured normal human fibroblasts indicated that treatment of cells with zinc before exposure to an alkylating agent enhanced cell survival by seven- to ninefold. To establish whether a similar zinc-induced protective response could be elicited in vivo, we conducted a preliminary experiment in which Balb/cJ female mice were treated with zinc (2 mg kg-1 body weight) or saline by intraperitoneal (i.p.) injection at 48, 36, 24 and 12 h before i.p. administration of the alkylating agent nitrogen mustard (4 mg kg-1 body weight). Of the animals that received saline before nitrogen mustard, 57% died as compared with only 20% in the group treated with zinc before administration of the alkylating agent. As was observed in the studies of cells in culture, the results described in this report may suggest the existence in Balb/cJ female mice of a zinc-mediated protective response against nitrogen mustard toxicity.

Previous studies with cultured human normal fibroblasts indicated that pretreatment of the cells with zinc for 12 h prior to exposure to the alkylating agent melphalan increased survival by seven- to ninefold over survival values obtained in cultures treated with drug only. Comparable pretreatment of cells derived from a variety of human tumors resulted in an increase in survival of 1.7-fold or less. To determine whether the limited responsiveness to zinc represented a general property of tumor cells (which would be characterized by a lack of highly zinc-responsive subpopulations contained within the parental tumor populations), a series of clones was prepared from the A101D human melanoma line and the A549 human alveolar cell carcinoma line. Cells from each clone were then challenged with melphalan with and without zinc pretreatment. Twenty-five percent of the tumor clones exhibited increased resistance to melphalan following pretreatment with zinc (range of 2.1- to 5.2-fold increase in survival), indicating that the parental tumor lines were highly heterogenous in regard to inducibility to a state of reduced sensitivity to melphalan. There was no evidence of a relationship between zinc-induced reductions in toxicity and induced elevations in total intracellular glutathione content, indicating that the primary effect of zinc is not directed toward elevating intracellular levels of glutathione.