Differential Kinase Activity Across Prostate Tumor Compartments Defines Sensitivity to Target Inhibition.

Cancer therapy often results in heterogeneous responses in different metastatic lesions in the same patient. Inter- and intratumor heterogeneity in signaling within various tumor compartments and its impact on therapy are not well characterized due to the limited sensitivity of single-cell proteomic approaches. To overcome this barrier, we applied single-cell mass cytometry with a customized 26-antibody panel to PTEN-deleted orthotopic prostate cancer xenograft models to measure the evolution of kinase activities in different tumor compartments during metastasis or drug treatment. Compared with primary tumors and circulating tumor cells (CTC), bone metastases, but not lung and liver metastases, exhibited elevated PI3K/mTOR signaling and overexpressed receptor tyrosine kinases (RTK) including c-MET protein. Suppression of c-MET impaired tumor growth in the bone. Intratumoral heterogeneity within tumor compartments also arose from highly proliferative EpCAM-high epithelial cells with increased PI3K and mTOR kinase activities coexisting with poorly proliferating EpCAM-low mesenchymal populations with reduced kinase activities; these findings were recapitulated in epithelial and mesenchymal CTC populations in patients with metastatic prostate and breast cancer. Increased kinase activity in EpCAM-high cells rendered them more sensitive to PI3K/mTOR inhibition, and drug-resistant EpCAM-low populations with reduced kinase activity emerged over time. Taken together, single-cell proteomics indicate that microenvironment- and cell state-dependent activation of kinase networks create heterogeneity and differential drug sensitivity among and within tumor populations across different sites, defining a new paradigm of drug responses to kinase inhibitors. SIGNIFICANCE: Single-cell mass cytometry analyses provide insights into the differences in kinase activities across tumor compartments and cell states, which contribute to heterogeneous responses to targeted therapies.

The Benefits of Omnivory for Reproduction and Life History of a Specialized Aphid Predator, Hippodamia convergens (Coleoptera: Coccinellidae).

The convergent lady beetle, Hippodamia convergens Guerin-Meneville, is a specialized predator of cereal aphids on the High Plains, completing its first generation each year in winter wheat, the resulting adults dispersing into summer crops and producing additional generations, contingent on the availability of aphids. In the present study, we tested the collective value of supplementary plant resources (sugars, pollen, and seedling wheat leaves), and small amounts of alternative prey, eggs of Ephestia kuehniella (Zeller) (Lepidoptera: Pyralidae), all provided together, for improving beetle life history and reproductive success even when suitable prey, Schizaphis graminum (Rondani) (Hemiptera: Aphididae), were provided ad libitum. Although a monotypic diet of S. graminum yielded slightly faster larval development and heavier adults than the omnivorous diet, preoviposition periods were extended and 21-d fecundities greatly reduced when this diet was continued through adult life, largely due to fewer oviposition days, although egg fertility was unaffected. The results highlight the critical importance of plant-derived resources even when suitable prey are not limiting. However, monotypic diet beetles that diapaused for 21 d in the presence of supplementary plant resources, plus moth eggs, achieved the same reproductive success as those reared on the omnivorous diet, with or without diapause, demonstrating that access to these resources post-emergence was sufficient to compensate for their absence during development. The diapause treatment itself had no impact on the fitness of beetles reared on the omnivorous diet, likely because neither its duration, nor the caloric restriction imposed, were sufficient to diminish reproductive effort.

How Efficient Is Fertilization by Traumatic Insemination in Orius insidiosus (Hemiptera: Anthocoridae)?

Traumatic insemination (TI) can be injurious to females, and females have evolved various paragenital structures to mitigate these impacts. We examined the mating behavior of Orius insidiosus (Say) and the consequences of single and double matings for female fitness. A total of 100 virgin females (4-6-d old) were directly observed while they mated with virgin males. Some of these females were mated a second time with a different, nonvirgin male 3-5 d later, after they oviposited in sunflower stems. Females were held in isolation, fed eggs of Ephestia kuehniella Zeller, and reproductive success was tracked for 30 d. Six females died during their first copulation (6%), and another within 48 h, without laying eggs. Four percent of the females died during their second copulations. Copulations lasting less than 90 s usually did not result in successful fertilization, and duration of copula was positively correlated with egg fertility in singly-mated females. Duration of copula was more than halved in second matings, twice as variable, and negatively correlated with 30 d fecundity. Thirty-seven percent of singly-mated females and 31% of twice-mated females were infertile, with fewer than half of all females producing 88% of all eggs. We conclude that O. insidiosus females are likely monandrous in the wild, and that TI in this species is inefficient, contributing to high variation in female fitness. Thus, mating involves a significant mortality risk for females, despite their possession of complex paragenital structures that ostensibly mitigate copulatory injury.