Considering hormones as sex- and gender-related factors in biomedical research: Challenging false dichotomies and embracing complexity

Sex and Gender in Myeloid and Lymphoblastic Leukemias and Multiple Myeloma: From Molecular Mechanisms to Clinical Outcomes

Biological sex and gender factors significantly influence the pathogenesis, progression, and treatment response in hematologic malignancies. This comprehensive review examines sex-specific differences in acute myeloid leukemia, acute lymphoblastic leukemia, chronic myeloid leukemia, and multiple myeloma through systematic analysis of the peer-reviewed literature published between 2014-2024 and identified through structured searches of PubMed, Web of Science, and MEDLINE databases. Epidemiological data demonstrate higher disease incidence (57% male vs. 43% female in MM, 63% male vs. 37% female in AML hospitalizations for ages 18-39) and inferior outcomes in male patients across malignancy types (5-year relative survival rates of 48.8% vs. 60.4% in females with AML), while female patients exhibit superior survival despite experiencing greater treatment-related toxicities. Our analysis reveals consistent sex-specific patterns in molecular mechanisms, including distinct mutational profiles, differences in immune system function, and sex-based pharmacokinetic variations that collectively suggest the necessity for sex-differentiated treatment approaches. The review identifies reproducible patterns across diseases, particularly in cytogenetic and molecular characteristics, with females demonstrating favorable prognostic mutations in leukemias and higher rates of chromosomal abnormalities in multiple myeloma. Despite these identifiable patterns, significant knowledge gaps persist regarding the underlying mechanisms of sex-based outcome differences. Incorporating sex and gender considerations into precision medicine frameworks represents a critical advancement toward optimizing treatment strategies and improving clinical outcomes for patients with hematologic malignancies.

Incorporating Sex-Diverse and Gender-Inclusive Perspectives in Higher Education Biology Courses

Inclusive teaching is teaching in a way that reaches all students in the classroom; this is beneficial for everyone, particularly for those with minoritized identities. Instructors play a critical role in scaffolding how students are exposed to and learn science content in the classroom. In this manuscript, we discuss how biology instructors can make their classrooms more inclusive with regard to sex and gender diversity content. Many topics in biology are based on androcentric, heteronormative, and oppressive framing, even though those lenses are more reflective of our own history and culture than they are of the diversity we see in nature. Here, we summarize information presented in the SICB 2024 workshop titled "Incorporating sex diversity and gender inclusivity in biology undergraduate classrooms" and provide instructors with (a) rationale for why inclusive teaching matters, (b) guidance on how to challenge unscientific views and make their curricula more sex diverse and gender inclusive, and (c) practical and easy-to-implement strategies for discussing "contentious" topics in the classroom. Incorporation of this material will be beneficial for students, for science and medicine, and for accurately representing the diversity found across the tree of life.

Testosterone, gender identity and gender-stereotyped personality attributes

Sex/gender differences in personality associated with gender stereotyped behavior are widely studied in psychology yet remain a subject of ongoing debate. Exposure to testosterone during developmental periods is considered to be a primary mediator of many sex/gender differences in behavior. Extensions of this research has led to both lay beliefs and initial research about individual differences in basal testosterone in adulthood relating to "masculine" personality. In this study, we explored the relationships between testosterone, gender identity, and gender stereotyped personality attributes in a sample of over 400 university students (65 % female assigned at birth). Participants provided ratings of their self-perceived masculinity and femininity, resulting in a continuous measure of gender identity, and a set of agentic and communal personality attributes. A saliva sample was also provided for assay of basal testosterone. Results showed no compelling evidence that basal testosterone correlates with gender-stereotyped personality attributes or explains the relationship between sex/gender identity and these attributes, across, within, or covarying out sex assigned at birth. Contributing to a more gender diverse approach to assessing sex/gender relationships with personality and testosterone, our continuous measure of self-perceived masculinity and femininity predicted additional variance in personality beyond binary sex and showed some preliminary but weak relationships with testosterone. Results from this study cast doubt on the activational testosterone-masculinity hypothesis for explaining sex differences in gender stereotyped traits and within-sex/gender variation in attributes associated with agency and communality.

Training in the implementation of sex and gender research policies: an evaluation of publicly available online courses

BACKGROUND

Recently implemented research policies requiring the inclusion of females and males have created an urgent need for effective training in how to account for sex, and in some cases gender, in biomedical studies.

METHODS

Here, we evaluated three sets of publicly available online training materials on this topic: (1) Integrating Sex & Gender in Health Research from the Canadian Institutes of Health Research (CIHR); (2) Sex as a Biological Variable: A Primer from the United States National Institutes of Health (NIH); and (3) The Sex and Gender Dimension in Biomedical Research, developed as part of "Leading Innovative measures to reach gender Balance in Research Activities" (LIBRA) from the European Commission. We reviewed each course with respect to their coverage of (1) What is required by the policy; (2) Rationale for the policy; (3) Handling of the concepts "sex" and "gender;" (4) Research design and analysis; and (5) Interpreting and reporting data.

RESULTS

All three courses discussed the importance of including males and females to better generalize results, discover potential sex differences, and tailor treatments to men and women. The entangled nature of sex and gender, operationalization of sex, and potential downsides of focusing on sex more than other sources of variation were minimally discussed. Notably, all three courses explicitly endorsed invalid analytical approaches that produce bias toward false positive discoveries of difference.

CONCLUSIONS

Our analysis suggests a need for revised or new training materials that incorporate four major topics: precise operationalization of sex, potential risks of over-emphasis on sex as a category, recognition of gender and sex as complex and entangled, and rigorous study design and data analysis.

Sex contextualism in laboratory research: Enhancing rigor and precision in the study of sex-related variables

Understanding sex-related variation in health and illness requires rigorous and precise approaches to revealing underlying mechanisms. A first step is to recognize that sex is not in and of itself a causal mechanism; rather, it is a classification system comprising a set of categories, usually assigned according to a range of varying traits. Moving beyond sex as a system of classification to working with concrete and measurable sex-related variables is necessary for precision. Whether and how these sex-related variables matter-and what patterns of difference they contribute to-will vary in context-specific ways. Second, when researchers incorporate these sex-related variables into research designs, rigorous analytical methods are needed to allow strongly supported conclusions. Third, the interpretation and reporting of sex-related variation require care to ensure that basic and preclinical research advance health equity for all.