Oxidative stress (OS) is an established hallmark of cancer and neurodegenerative disorders (NDDs), which contributes to genomic instability and neuronal loss. This review explores the contrasting role of OS in cancer stem cells (CSCs) and NDDs. Elevated levels of reactive oxygen species (ROS) contribute to genomic instability and promote tumor initiation and progression in CSCs, while in NDDs such as Alzheimer’s and Parkinson’s disease, OS accelerates neuronal death and impairs cellular repair mechanisms. Both scenarios involve disruption of the delicate balance between pro-oxidant and antioxidant systems, which leads to chronic oxidative stress. Notably, CSCs and neurons display alterations in redox-sensitive signaling pathways, including Nrf2 and NF-κB, which influence cell survival, proliferation, and differentiation. Mitochondrial dynamics further illustrate these differences: enhanced function in CSCs supports adaptability and survival, whereas impairments in neurons heighten vulnerability. Understanding these common mechanisms of OS-induced redox imbalance may provide insights for developing interventions, addressing aging hallmarks, and potentially mitigating or preventing both cancer and NDDs.

The highly conserved Notch pathway, a pillar of juxtacrine signaling, orchestrates intricate intercellular communication, governing diverse developmental and homeostatic processes through a tightly regulated cascade of proteolytic cleavages. This pathway, culminating in the migration of the Notch intracellular domain (NICD) to the nucleus and the subsequent activation of downstream target genes, exerts a profound influence on a plethora of molecular processes, including cell cycle progression, lineage specification, cell–cell adhesion, and fate determination. Accumulating evidence underscores the pivotal role of Notch dysregulation, encompassing both gain and loss-of-function mutations, in the pathogenesis of numerous human diseases. This review delves deep into the multifaceted roles of Notch signaling in cellular dynamics, encompassing proliferation, differentiation, polarity maintenance, epithelial–mesenchymal transition (EMT), tissue regeneration/remodeling, and its intricate interplay with other signaling pathways. We then focus on the emerging landscape of Notch aberrations in gynecological pathologies predisposing individuals to infertility. By highlighting the exquisite conservation of Notch signaling in Drosophila and its power as a model organism, we pave the way for further dissection of disease mechanisms and potential therapeutic interventions through targeted modulation of this master regulatory pathway.

Neurodegeneration and cancer are fundamentally distinct disorders: one signifies gradual neuronal loss while the latter signifies uncontrolled cell growth and survival. However, emerging evidence explores an inverse association between these conditions, suggesting that they do not arise from independent biological processes. Understanding the context-dependent behaviour of major pathways (for example, p53, PI3K/AKT/mTOR, Wnt, and immune–stress signaling) remains pivotal in elucidating the relationship between these two diseases. Pathways promoting early-life fitness, tissue repair, and tumor suppression in dividing cells can become detrimental later in life for post-mitotic neurons. Cross-species genomics studies reveal how evolution has repeatedly adapted these shared networks to balance cancer resistance with survival. Research on species exhibiting exceptional longevity and disease resistance, including naked mole rats and bowhead whales, shows that cancer resistance and longevity are not fixed traits but rather are controlled by precise regulatory mechanisms. In this review, we integrate insights from broad species genomics and multi-omic and single-cell studies to understand how evolutionarily conserved molecular crosstalks diverge at the interface of cancer and neurodegeneration.