Metastasis, or the spread of cancer to a secondary site, is responsible for most cancer-related deaths. The tissue-specific environment that disseminated tumor cells experience influences whether they will proliferate and colonize the tissue, remain dormant, or die. Skeletal muscle (SkM) is one of the rarest sites for metastasis, despite making up nearly half of human body mass. What makes SkM so resistant to metastasis? We set out to test the hypothesis that the mechanical nature of SkM is responsible for the lack of metastases at this site. To do so, we used the mdx mouse model of Duchenne muscular dystrophy to probe if the destruction of SkM structure and function would make it a more hospitable host to disseminated tumor cells. Wild type and mdx mice were intramuscularly injected with EO771 murine mammary tumor cells and monitored for tumor outgrowth using bioluminescent imaging. Preliminary results suggest that tumor growth is increased in dystrophic (e.g. dysfunctional muscle) versus wild-type mice. A complementary and more reductionist approach to test whether mechanics influences tumor colonization of muscle is to employ a culture model that allows tumor cells seeded on top of a SkM layer to experience mechanical stretching akin to the contraction/relaxation movements of muscle. To accomplish this, we constructed a device that applies a cyclic stretch to a 3D organotypic SkM culture model on a flexible silicone plate. We predicted that stretching would reduce tumor cell survival, when compared to no stretching. While these experiments are in progress, we believe that these data may elucidate a relationship between mechanical activity and suppression of tumor outgrowth in SkM. This work will contribute to a more complete understanding of how SkM avoids tumor colonization and could inform future approaches that leverage tissue mechanics to treat or prevent metastasis.

Fluorescent biosensors are a vital tool in the goal to decipher the complexity of neural networks. Genetically encoded fluorescent indicators (GEFIs) are protein-based sensors that increase in fluorescence upon ligand binding and allow for passive monitoring of neuronal signals. However, the development of such sensors is limited by the slow throughput of traditional protein engineering which has long engineering cycles of new plasmid variants. Our project aims to tackle this problem by developing a high-throughput sensor engineering platform that can effectively generate and screen unbiased genetic libraries of GEFIs in mammalian cells. Our platform can identify high performing sensor variants on a custom microarray and effectively isolate and recover their genetic material. Our new platform will be used to develop a sensor for the μ-Opioid receptor (MOR), which is a G-protein coupled receptor that is involved in opioid addiction. Our experiments have already developed a MOR sensor that surpasses the standard in the literature and we will continue to optimize it for maximum spatial and temporal precision. The development of a MOR sensor through this iterative process allows researchers to further investigate the molecular mechanisms underlying the pathology of addiction and provides a novel platform for protein engineers to more efficiently develop a wide variety of biosensors.

As a student of both Religion and International Relations, I am intrigued and perplexed by the presence – or absence – of sanctity within international systems. My senior capstone, which I conceived of and researched myself, studies the Tlingit potlatch and its use of the sacred in international relations between the Sitka Tlingit Nation and the Russian Empire (prior to 1867), as well as the United States government (after 1867). Using secondary sources, the anthropological and historical work of Dr. Sergei Kan, and definitions of the sacred as discussed in the works of Mircea Eliade, I ask several questions to evaluate international relations theory. Firstly, what is the sacred and how does it connect us? Secondly, how was the sacred used in the Tlingit potlatch, and how did the Russians and Americans differ in their interactions within this space? Finally, how might a closer look at the potlatch help me understand one form of Indigenous international relations and how can the use of the sacred challenge assumptions made by predominantly white western international relations theorists? The Tlingit potlatch served as the primary space for international relations through the prescribed roles of “host” and “guest.” My research has led me to conclude that the Russian Orthodox Church leaders accepted their role as guests, thereby maintaining their sovereignty and the sovereignty of the Tlingit, and by extension, preserving international relations between the two groups. American Presbyterians, however, sought to conquer and control Tlingit sanctity, effectively dissolving the potlatch, Tlingit sovereignty, and the possibility of maintaining international relations between the communities. With these discoveries in mind, I ask, “What might Tlingit Elders tell us about how to conduct international relations, and what do we do with that?” By asking this question, I attempt to elevate Indigenous voices in the field of international relations and revolutionize the ways in which international diplomacy is conducted by allowing space for empathy, sanctity, and trust.

The locus coeruleus (LC) is a small nucleus of noradrenergic neurons in the pons, which, despite its size, has broad projections throughout the central nervous system (CNS). Functionally, the LC is believed to be involved in various critical functions, including the physiological response to stress, as well as mediating arousal. Previous investigations have demonstrated that optogenetic activation of the LC at a tonic frequency promotes wakefulness in rodents. While this observation causally implicates LC function in wakefulness, it is still not known how the LC is endogenously controlled to mediate arousal. One potential candidate in this control is the peptide nociceptin and its cognate receptor, the nociceptin opioid peptide receptor (NOPR), both of which are highly expressed around the LC. To investigate, we first conducted two pharmacological experiments using the NOPR agonist Ro64-6918 to assess its effects on locomotion and on the activity of LC noradrenergic neurons. To determine where the endogenous nociceptin signal to the LC originates, we performed an intracranial injection of a Cre-dependent retrograde virus (AAV2-DIO-eYFP) into the LC of a mouse expressing Cre recombinase in nociceptin-expressing neurons. We observed that Ro64-6198 (10 mg/kg) strongly reduced open field locomotor activity compared to vehicle treatment. Using in vivo 2-photon calcium imaging (GCaMP6s), we found that Ro64-6198 (5 mg/kg) profoundly reduced LC noradrenergic neuron activity. Wakefulness appeared reduced in both in vivo experiments. Finally, we identified nociceptin-expressing cells projecting to the LC in the peri-LC as well as a long-range projection from the bed nucleus of the stria terminalis (BNST). Together, these studies suggest that nociceptin acting on LC noradrenergic neurons reduces arousal, and that the endogenous sources of nociceptin may originate in the peri-LC and BNST. Future studies will investigate nociceptin-expressing neuron activity during sleep/wake transitions and whether this activity is sufficient to alter wakefulness.

Midfacial hypoplasia (MFH) is a disorder characterized by underdevelopment of the upper jaw, nose, and cheek bones which can impede feeding and breathing. The causes of MFH are not yet fully understood, but a novel pig model suggests that the posterior nasal septal cartilage is ossified, or converted to bone, prematurely in pigs with MFH. Thus, we predict that there is an increase in the amount of ossified septum in pigs with MFH. To test the hypothesis that pigs with MFH have increased septal ossification, we measured the area of the entire septum and the fraction occupied by bone on CT scans taken from 20 pigs with MFH and 10 normal pigs ages 3-10 months using ImageJ. All measurements were standardized for size by dividing by skull length. We compared MFH and normal pigs with t-tests using excel. As predicted, the fraction of ossified septum was greater in MFH pigs (0.39 ± 0.08) than normal pigs (0.25 ± 0.06, p<0.0001). The nasal septal cartilage is thought to be the primary driver of facial growth. A decrease in septal cartilage due to increased ossification may hamper normal growth and lead to MFH. Premature ossification of the nasal septal cartilage may also be a cause of MFH in humans and this finding could be used to develop better treatments for this disorder.

Kaposi’s Sarcoma (KS) is a highly vascularized tumor, which affects AIDS patients worldwide and remains endemic to sub-Saharan Africa. Kaposi’s Sarcoma-associated Herpesvirus (KSHV) is the etiological agent of KS and its latent infection is involved in tumor formation and the induction of angiogenesis in the spindle cell, a cell of endothelial origin and the main proliferating cell type in a KS tumor. Previous RNA-Seq data obtained by our group showed that osteopontin (opn), a secreted protein known to act as a ligand for integrin receptors that activate signaling cascades that promote angiogenesis, is highly upregulated at the transcript level during KSHV latent infection of endothelial cells. To determine whether opn is required for the activation of angiogenesis in KSHV latently-infected endothelial cells, we used CRISPR-lentiviral constructs to knock out opn and evaluate changes in angiogenic phenotypes upon KSHV infection via cell proliferation, tubule formation, and cell migration assays. Preliminary results reveal a significant reduction in tubule formation in opn knockout KSHV-infected endothelial cells. This finding suggests that opn upregulation in such cells is responsible for the activation of this angiogenic phenotype. Future experimentation will include evaluating how KSHV induces the upregulation of opn by infecting wild-type endothelial cells with mutant viruses lacking certain latency protein genes and evaluating differences in opn transcriptional and translation, as well as evaluating the mechanisms by which opn activates tubule formation in KSHV latently-infected endothelial cells. Identifying  the drivers of angiogenesis in KSHV-infected endothelial cells will aid the characterization of therapeutic targets for KS progression in such cells, given that KS tumors are highly angiogenic from its early stages.

The pupillary light reflex (PLR) curve is an important point-of-care biomarker for the diagnosis of traumatic brain injury (TBI). Using PLR, first responders can determine the severity of TBI in the field and direct patients to a trauma center where staff can continually assess PLR to monitor TBI severity. Manual pupillometry, the most commonly available method for first responders and most clinicians wishing to assess PLR, is qualitative and often inaccurate. The current gold-standard device for PLR measurement is digital infrared pupillometry, but such devices are fragile and expensive. Our research team has developed a smartphone-based pupillometer (PupilScreen) with the ability to assess PLR using a standard iPhone, assisted by a cloud-based neural network. To demonstrate the feasibility of using PupilScreen in a realistic clinical setting and compare the accuracy of the device to the current clinical gold-standard, we have built an annotated dataset of the PLR in n=120 patients with TBI who are hospitalized in a neurological intensive care unit. Pupillometry is performed using the mobile device and the gold-standard digital infrared pupillometer. Pupil videos are manually annotated and used in the further training of our machine learning algorithm that generates a PLR curve for each patient. We anticipate that our technology will demonstrate accuracy in assessing the PLR that exceeds that of manual pupillometry and is at least equivalent to the gold-standard digital pupillometer. This technology has the potential to alleviate the current undertreatment of many TBI patients in the United States and abroad that results from a lack of accurate and cost-effective pupillometry equipment.

Δ⁹-tetrahydrocannabinol (THC) is the primary psychoactive compound found in Cannabis sativa. The psychoactive and cannabimimetic behaviors associated with THC have been well described as being dependent on the partial agonist activity of THC at the endogenous cannabinoid 1 receptor (CB₁R). We are investigating the direct action of THC on the medial prefrontal cortex (mPFC, a brain region primarily responsible for executive function), and the effects of adolescent THC exposure on µ-opioid receptor (MOR) expression in adult periaqueductal grey (PAG, a brain region involved in opioid-mediated pain inhibition). To increase our understanding of the cannabimimetic behavioral effects of THC, and its direct pharmacological action in the brain, it is important to map the neuro-anatomical expression of target proteins. We examined expression patterns of CB₁R and MOR in the mPFC and the PAG, respectively. To do this, we utilized a form of in situ hybridization, RNAscope. We leveraged RNAscope by preparing tissue samples from brain regions of interest for treatment with mRNA-specific probes, allowing us to target CB₁R and MOR mRNA. After a series of washes and incubations, these fluorescent probes hybridize to our target mRNAs and allow us to visualize their expression under a confocal microscope. Analysis of mRNA expression informs us on the localization of the CB1R/MOR and known neuron types within our brain regions of interest. After imaging, we are able to utilize HALO software to analyze the levels of expression and co-localization of CB₁R/MORs with neuronal markers for glutamatergic and GABAergic neuron types. By creating and optimizing a workflow for extraction, preparation, hybridization, and analysis, we determined CB₁R mRNA is primarily co-localized with glutamatergic neurons in the mPFC. Moving forward, we are utilizing this RNAscope technique to investigate differential CB₁R expression GABA interneuron subpopulations in the mPFC. (Funded by DA051558)

 Mu-opioid receptors (MOR) are expressed on populations of neurons within the brain. Exogenous activation of these receptors by drugs of abuse, such as heroin and fentanyl, causes feelings of euphoria and can be highly addictive. During natural behavior, MORs in the brain are activated by the endogenous ligand enkephalin. Spiny projection neurons (SPN) in the nucleus accumbens (NAc) are known to express enkephalin and likely release it during neural activity. It is known that these enkephalin SPNs can be either excited or inhibited while animals consume natural rewards. However, it remains unclear whether these functionally distinct enkephalin SPN populations are anatomically intermixed or are anatomically separated within NAc. In this study, we used 2-photon calcium imaging through endoscopic lenses to examine the neural activity of enkephalin SPNs in NAc while mice consumed sucrose rewards. We characterized the reward-excitations or reward-inhibitions of individual enkephalin SPNs over multiple imaging sessions. Through precise post-mortem histological examination, we then verified the anatomical placements of our endoscopic lenses and associated the relative anatomical location of neuronal populations to their reward-related neural activity. We found that enkephalin SPNs in anterior NAc were consistently reward-inhibited while enkephalin SPNs in posterior NAc were reward-excited. This is the first demonstration of anterior-posterior axis differences in the reward-related modulation of enkephalin SPNs and is a key step to understanding how opioidergic neurons function in natural reward behavior.

Environmental stress and threat influence feeding behavior in animals, but how that interaction occurs is still largely unclear. Neurons in the bed nucleus of the stria terminalis (BNST), part of the extended amygdala, have dense projections to the parabrachial nucleus (PBN) in the brainstem. We have uncovered projections in these neural circuits that link the modulation of feeding and threat assessment in mice. This project aims to investigate and characterize these previously unrecognized neural circuits with the incorporation of a variety of optogenetic, surgical, and histological techniques. We used Cre-dependent anterograde and retrograde viral tracers in order to trace the anatomy of these neural circuits, and found functional projections from inhibitory (GABA) and excitatory (glutamate) populations in the BNST to neurons in the PBN. We also used translating ribosome affinity purification (TRAP) to isolate the mRNA of these projections. This proved useful in separating and identifying the molecular expression profile of different GABAergic and glutamatergic subpopulations. Furthermore, we used a variety of behavioral assays to determine the BNST-PBN circuits’ role in feeding and threat-response behavior. We used fiber photometry to track the activity of GABAergic (vGAT) and glutamatergic (vGLUT2) populations during these behaviors, and found that vGAT and vGLUT2 populations have differing roles in threat and feeding behaviors. vGAT neurons increase their activity during feeding and decrease in response to threat, while vGLUT2 neurons decrease their activity during feeding and increase in response to threat. We also used optogenetic activation of these neurons to determine their causal role in behavior. With activation, vGAT populations drive place preference, operant positive reinforcement, and increased feeding. Conversely, vGLUT2 populations drive place aversion, operant negative reinforcement, and reduced feeding. These findings characterize the distinct nature of BNST-PBN neural circuits and the mechanism behind the evaluation of threatful stimuli and the integration of feeding.

The female reproductive tract must maintain normal reproductive functions while also being able to elicit immune responses to sexually transmitted microbes and viral pathogens. In response to virus exposure, the balance of these two functions can determine the outcome of infection and disease through alteration of vaginal mucosa integrity. Recent in vivo research in our laboratory revealed that vaginal infection by Zika virus (ZIKV), an emerging mosquito-transmitted flavivirus that is also sexually transmitted among humans, induces epithelial cell-specific innate immune response that accelerates a homeostatic form of cell death known as cornification. We hypothesize that specific processes in vaginal epithelial cells mediate cornification in response to ZIKV infection, and that this cornification may alter barrier properties, innate-adaptive immune crosstalk, and ultimately, the degree to which ZIKV disseminates from the female reproductive tract. We therefore analyzed and compared vaginal epithelial cell infection by both African and Asian lineage ZIKV strains using traditional 2-dimensional cell culture and organotypic 3-dimensional culture infection models. Differences in viral infection and replication kinetics, and innate immune response were characterized through RT-qPCR, immunoblot analysis, cell imaging, and viral plaque assay. Ongoing analyses are expected to reveal the application of organotypic 3-dimensional cultures in capturing in vivo qualities of vaginal epithelial cell/ZIKV infection and response compared to 2-dimension cultures. These studies will provide insights for application of vaginal epithelial cell culture models of ZIKV infection that encapsulates the complex functional and structural aspects present in vivo.

Antiseizure medications (ASM) may contribute to adverse fetal outcomes in pregnant women with epilepsy (WWE). Folate processing (methylenetetrahydrofolate reductase, MTHFR) gene abnormalities are common in women with epilepsy and depression. The enzyme product of this gene is a component of the metabolic pathway that makes folate bioavailable through methylation, critical for maintaining adequate serum folate levels. Folate is known to be crucial for fetal development, namely in the prevention of spina bifida and other neural tube defects (NTDs). The teratogenesis of some ASM in combination with genetic polymorphisms put WWE at higher risk for infertility, miscarriage, and/or major fetal malformations. L-methylfolate supplements may bypass deficiencies in the MTHFR-mediated folate metabolism pathway, yet their use in WWE during gestation or on fetal development is not well studied. We hypothesized that supplementation with L-methylfolate and methylcobalamin (methylated B12) may support better perinatal and fetal outcomes in pregnant WWE. We examined pregnancy histories of three WWE who supplemented with either folate or L-methylfolate and methylcobalamin (methylated B12) during pregnancies. Their pregnancy outcomes (both in conception and gestation) as well as mood stability improved with supplementation. L-methylfolate and methylcobalamin supplementation merits further study in WWE who have MTHFR mutations, fertility, recurrent miscarriage and/or depression histories.

Pigs often have an anterior crossbite (underbite), where the maxillary incisors (upper anterior teeth) are positioned behind the mandibular incisors (lower anterior teeth) instead of in front as found in a normal dental relationship. In humans, when this condition is severe, proper feeding, speaking, and breathing can be impeded. An anterior crossbite can occur due to dental and/or skeletal malformations. Retro-inclination of the maxillary incisors or excessive pro-inclination of the mandibular incisors are dental contributors to this problem, whereas excessive growth of the mandible (lower jaw) or deficient growth of the maxilla (upper jaw) are skeletal causes. Pigs are a novel model for anterior crossbites in humans, yet it is unclear which dental or skeletal condition is the primary cause in pigs. Therefore, it is necessary to characterize this condition in pigs to translate this model to humans effectively. The purpose of this project is to determine if improper inclination of the incisors, mandibular prognathism, or maxillary retrognathism is the primary cause of anterior crossbites in pigs. A total of 150 pig skulls (120 dry skulls and 30 CT images) were included in this study. The angle of inclination of maxillary and mandibular incisors, length of the mandible, and length of the maxilla (estimated by the length of the hard palate) were measured in dry skulls using a metric protractor and ruler to the nearest degree or mm. The same measurements were taken on CT images using ImageJ software. Measurements will be compared between normal and affected pigs using t-tests and correlated to the severity of anterior crossbite using Pearson correlations. Based on the data I have acquired, I expect that the primary cause of anterior crossbites in pigs is maxillary retrognathism, also termed maxillary hypoplasia, and thus serves as a model for this specific condition in humans.

The purpose of this project is to determine if there are compensatory changes to the height and width of the skull as a result of midfacial hypoplasia (MFH) in pigs. Secondarily, this research aims to determine if the ability to respirate may be impacted because of changes in the anatomy of the airway. MFH is a malformation of the face in which the upper jaw, cheekbones, and eye sockets grow less than the rest of the face, often resulting in a “bug-eyed” appearance and/or an “underbite”. In severe cases, MFH can cause dental crowding and airway obstruction. By gaining a better understanding of the causes and consequences of midfacial hypoplasia, there can be better progress in the prevention and treatment of this sometimes life-threatening malformation. Methods: This project utilized 158 skulls, including 132 dry skulls which were hand measured using a metric ruler, and the remaining 26 skulls are in CT scan format. These skulls are being measured using the program AVIZO. Out of the 158 skulls, 68 have MFH. Each pig skull provides a series of 6 measurements. To determine if there are changes to the height and width of the skull, I measured the snout height and width, and calvarial height and width. To determine if the airway is affected, I measured the choanal height and width. Using the measurements from the total of 158 skulls, I plan to compare normal pigs to pigs with MFH by using t-tests and by correlating the measurements based on the severity of MFH using Excel. The results from this project will render insight to the causes and consequences of this malformation.

Neuropeptide S (NPS) is a neuropeptide produced primarily in two regions of the hindbrain, the locus coeruleus (LC) and the Kolliker-Fuse nucleus. The LC-NPS population is particularly interesting because of the LC’s role in norepinephrine production and subsequent transmission throughout the brain. Previous work has found that when NPS is injected into the amygdala, it results in an anxiolytic phenotype, implicating NPS and its G-protein coupled receptor (NPSr1) in anxiety-related behaviors. Using fluorescent in situ hybridization, a method which allows visualization of single RNA molecules within cells via fluorescent probes, we found preliminarily, that the orbitofrontal cortex (OFC) has dense expression of NPSr1 RNA. This is significant as the OFC is involved in higher-order cognition including social, reward-learning, and anxiety-like behaviors. For example, OFC neurons respond to social interaction as well as food cues, and inactivation of the OFC results in increased anxiety-like behavior. The LC is also known to send projections to the OFC that have been largely unexplored. Therefore, to better understand and characterize the connection between the LC and OFC we utilized in vivo fiber photometry to assess endogenous OFC-NPSr1 activity during reward-learning, social interaction, and innate behaviors. Our studies aim to uncover the functional role of LC-NPS release in the OFC.

Reward is a driving force for animal and human behavior. Reinforcing behaviors with rewards leads to enhanced learning ability, which can either promote behaviors that increase survival, or lead to maladaptive behaviors. The nucleus accumbens (NAc) and ventral tegmental area (VTA) are brain regions established to be involved in reward processing and have significant neural connectivity. Recent studies have identified a long-range GABAergic neural circuit connecting these two regions, however previous studies focus primarily on dopaminergic neurons. These inhibitory GABAergic neurons synapse with cholinergic interneurons within the NAc shell (NAcSh). Further, the dorsal and ventral subdivisions within the NAcSh have been shown to have different neural connectivity. To investigate the role of this circuit, I performed fiber photometry recordings of neural activity in GABAergic terminals in the dorsal and ventral NAcSh during reward reinforced behavior in mice. The recordings show an increase in GABAergic neural during reward consumption in the ventral, but not the dorsal, NAcSh. I also recorded the activity of NAcSh cholinergic interneurons as well as acetylcholine activity in the dorsal and ventral NAc shell. These recordings show that cholinergic neural activity as well as acetylcholine activity are reduced during reward consumption in the ventral, but not dorsal, NAcSh, reflecting the inhibition by the GABA neurons during this time. I also used the inhibitory photo-activatable chloride pump JAWS to inhibit GABAergic projections during reward consumption, finding that animals made reduced reward seeking events and consumed fewer rewards when JAWS is activated. Collectively, these results indicate GABAergic projections from the VTA to specifically the ventral NAcSh function in reward reinforcement by inhibiting cholinergic activity during reward consumption. These results characterize a previously unknown neural circuit and help us better understand psychiatric disorders like depression and addiction that impact these circuits. 

In 2020, the COVID-19 pandemic caused students living in rural areas to experience exacerbated educational disparities. This included familial financial stresses, which also pushed many migrant students living in rural communities to prioritize work over school. The pandemic shed light on educational disparities featured in rural public-school education systems. The purpose of the study was to examine how the education trajectory of students in rural communities had been affected by the social and economic impacts of COVID-19. To accomplish this purpose, we examined the extent to which familial needs impacted students’ post-high school educational plans, how financial strain influenced their post-graduation choices, and how students practiced resourcefulness and resilience despite experiences of economic hardship. In this community-based qualitative research project, we conducted semi-structured interviews with Eastern Washington high school seniors who are 18 years of age or older and used a phenomenological thematic analysis to gather themes related to our research questions. As part of the research, we collaborated with a community advisory committee composed of teachers and recent high school graduates from Eastern Washington communities to develop the project’s research methods and to ensure the analyses and interpretation of interviews are reflective of the students’ experiences. We predicted that students will plan to alter their post-high school paths to accommodate their families’ needs. Anti-racist - strength-based - frameworks were used to make academic support recommendations for students in rural communities. Ultimately, our study can help inform collaboration with community members to find solutions so we can best support students and encourage them as they navigate pathways after high school graduations.

According to the 1991-2015 Combined National Youth Behavioral Risk Surveys, Native Hawaiian/Pacific Islander adolescents had rates of attempted suicide two times higher than non-Hispanic Whites. However, there is a great lack of research and resources dedicated to Pacific Islander mental health. This literature review seeks to understand the unique experiences of Pacific Islanders in regards to their mental health. I reviewed 10 research articles concerning mental health in the Pacific Islander community, with a focus on adolescence and emerging adulthood since this is a critical developmental period that impacts the lifetime health outcomes of a population. These studies range in focus from documenting personal experiences to general disparities that impact this population. In the literature, I found that Pacific Islander youth experienced higher rates of mental health issues such as depression, anxiety and psychological distress in comparison to non-Hispanic whites and other minority groups like Hispanics in the United State. These findings signal that future research should focus on identifying and better understanding the risk and protective factors that impact mental health outcomes in Pacific Islander communities. This literature review helps summarize the small existing literature, identify gaps in research about Pacific Islander mental health, and inform future research questions.

Statistical models are fundamental to identify and understand cancerous tendencies and properties in our bodies. Much of the current research focuses on the relationships between binary gene expressions and cancer incidence, which often leads to uninterpretable models due to complex relationships between gene expressions. Instead, using knot identification and analysis in nonlinear modeling creates more interpretable trends. Using data by age, sex, and race from the National Cancer Institute, we analyze leukemia incidence in the period 1975-2017 using regression splines, a technique that partitions the model into several piecewise functions at various knots in the covariate space. Knot locations are chosen to provide interpretable results and minimize the least squared error, which allows for inference based on techniques from linear regression. After ANOVA forward selection for the polynomial regression model and general cross-validation for the natural cubic spline, the knot points converged on an interval between 1985 to 1986. This suggests that the female cancer incidence rate developed an exponential cancer growth in an interval of 1 year. Therefore, to oppose future exponential incidence increases in female rate, conducting medical research for genomic or environmental causation factors will be more explicit and accelerated due to the specificity of the 1985 to 1986 time inverval.