bioRxiv Science⌕ Search

bioRxiv · 10.1101/2025.02.10.637526

Nanoprotrusion enlargement conducts cytocapsular tube elongation along the path of least resistance

Abstract

Cancer metastasis is a major source of cancer lethality. Recently, we reported that the ATP-dependent calcium pump PMCA2 is enriched in cytocapsular membranes as biomarker of native malignant tumors. Cytocapsular tubes (CCTs) provide membrane-enclosed freeways for protected and bi-directional cancer metastasis in cytocapsular tumor network systems (CTNSs). It is obscure how CCTs initiate and elongate in heterogeneous human tissues and organs against diverse blocks of resistance. Here, we report that thin CCT nanoprotrusions (NPs) enlarge in directions of least resistance to grow into enlarged NPs. Subsequently, enlarged NPs develop into initial CCTs (ICCTs) followed by development into full CCTs. The full CCTs elongate in paths of least resistance over long distances, as observed in 34 kinds of human tissues and organs. Sideways CCT branching proceeds via a NP bifid format, which increases CCT numbers and expands 3D CCT networks in tissues. CCT regeneration additionally drives repeated cancer metastasis. CCT superstructures facilitate full cancer metastasis. This study demonstrated nanoprotrusion-conducted CCT elongation along the path of least resistance and branching morphogenesis in bifid branching style. The cytocapsular membrane system expansion mechanics of CCTs and CCT networks described here may open new avenues for native cancer research and CTNS-targeted effective cancer cure. (200 words) Significance statementThe recent identification of PMCA2 as a biomarker for malignant tumors, allows imaging very early native cancer growths on culture plates in vitro and in human bodies as revealed from snapshot images of numerous cancer biopsies in vivo. Aggressive cancer metastasis, cancer progression, repeated cancer relapse, limited cancer therapy outcomes, pan-cancer drug resistance, immune cell attack escape, and immunotherapy non-responsive "cold" tumors are unmet challenges in clinical cancer therapy. However, the cytocapsular tube (CCT) elongation mechanisms in human tissues/organs with heterogeneous resistances are still unclear. Here, we report that CCT nanoprotrusions (NPs) extend into enlarged NPs apparently towards tissue of least resistance and subsequently develop into initial CCTs. Intracytocapsular oncocells released cytocapsulasomes to fuse into the membranes of initial CCTs and increase cytocapsular membrane areas. This enables oncocells to push and deform initial CCT membranes and to generate new CCTs with new nanoprotrusion layers. Furthermore, CCT branching morphogenesis develops in a bifid format, significantly increasing CCT numbers and expanding 3D CCT networks in all kinds of human tissues. CCT superstructures promote complete cancer metastasis in AMCC complexes. Repeated CCT regeneration drives repeated cancer relapses. This study reveals the CCT elongation laws, and elucidates that CCT elongation and branching morphogenesis drives cytocapsular membrane protected cancer metastasis, and that repeated CCT regeneration promotes repeated tumor relapses in vivo.

Explore related subjects

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

Yi, T., Wagner, G.. 2025-02-13. Nanoprotrusion enlargement conducts cytocapsular tube elongation along the path of least resistance. https://doi.org/10.1101/2025.02.10.637526

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related preprints

m6A-Driven Intratumoral Cholesterol Biosynthesis Fuels Castration-Resistant Prostate Cancer Progression

Both nuclear pore complexes (NPCs) and RNA N6-methyladenosine (m6A) machinery are indispensable for proper cellular function. Although their collaborative roles in the nuclear export of messenger RNAs (mRNAs) have been reported, it remains ambiguous whether and how this collaboration may contribute to cancer progression. Here we identify a functional cooperation between NPCs and m6A signaling that promotes the development of castration-resistant prostate cancer (CRPC). We showed that nuclear export of m6A-modified mRNAs, mediated by the interaction between RNA methyltransferase METTL3 and the nucleoporin NUP93, is functionally coupled to cholesterol biosynthesis. Given that cholesterol-fueled intratumoral androgen production is one of the mechanisms driving CRPC, we demonstrated that overexpression of the wild-type METTL3 or NUP93, but neither the enzymatically dead METTL3 nor the mutant NUP93 that loses METTL3-interacting capability, elevates intracellular levels of androgens, activates AR signaling under castrate condition, and promotes androgen-independent growth of prostate cancer cells both in vitro and in vivo. Importantly, pharmacological inhibition of METTL3 or targeted demethylation on mRNAs encoding key cholesterol biosynthesis enzymes effectively suppressed CRPC malignancy. Together, these findings uncover a therapeutically targetable m6A-METTL3-NUP93 axis that links nuclear mRNA export and metabolic reprogramming to fuel CRPC progression, providing a conceptually new strategy for the treatment of this lethal disease.

cancer biology↗

ST6Gal2 promotes α2,6-sialylation and aggressive phenotypes in neuroblastoma cells

Neuroblastoma is the most common extracranial solid tumor of childhood. Its clinical behavior ranges from spontaneous regression to lethal, treatment-refractory disease. Aberrant 2,6-sialylation contributes to aggressive phenotypes in many cancers, but the role of ST6Gal2, a neural-enriched 2,6-sialyltransferase, in neuroblastoma is largely unexplored. Here, we examine the clinical and functional significance of ST6Gal2 in neuroblastoma. In two independent public cohorts (SEQC, n=498; Kocak, n=649), high ST6GAL2 expression was associated with significantly worse overall and event-free survival. In the SEQC cohort, ST6GAL2 expression was higher in high-risk and MYCN-amplified tumors, varied across International Neuroblastoma Staging System stages, and correlated positively with a mesenchymal transcriptional signature (Spearman {rho}=0.181). The mesenchymal correlation was reproduced in the Kocak cohort ({rho}=0.204). Stable shRNA-mediated knockdown of ST6GAL2 in SK-N-AS and SK-N-BE(2) cells reduced proliferation and viability, impaired wound closure, and decreased migration and invasion. In preliminary experiments in SK-N-AS cells, ST6GAL2 knockdown reduced binding of Sambucus nigra agglutinin, consistent with a role for ST6Gal2 in 2,6-sialylation. Together, these findings link ST6Gal2 expression to aggressive clinical and transcriptional features and pro-tumorigenic phenotypes in neuroblastoma and nominate ST6Gal2-mediated sialylation as a candidate pathway for mechanistic study.

cancer biology↗

Unsupervised transcriptomic analysis of paired pre- and post-treatment specimens reveals divergent chemoimmunomodulatory induction trajectories in breast cancer

The immunomodulatory effects of chemotherapy (chemoimmunomodulation; CIM) are clinically consequential and heterogeneous, yet no systematic framework exists for classifying the immunomodulatory trajectory a tumor follows in response to treatment (CIM trajectory). Here, we present the CIM Induction Classifier (CIMIC), an unsupervised clustering pipeline leveraging delta gene expression across 3,189 CIM-related genes to classify specimens chemoimmunomodulatory trajectory. Applied to two pre- and post-chemotherapy breast cancer (BC) datasets (NKI/SMC, N = 36; NEO, N = 19) and nine epirubicin-perturbed triple-negative BC (TNBC) cell lines, CIMIC identified two divergent CIM trajectories: a functional CIM (Fun-CIM) trajectory, broadly conserved across tumors and cell lines and characterized by induction of inflammatory cell death, antigen presentation, viral mimicry, and adaptive immune activation programs, and a dysfunctional CIM (Dys-CIM) trajectory, characterized by induction of proteostatic and metabolic stress-adaptation programs, reduced immune cell abundances and cytotoxic activity, and enrichment of aggressive BC subtypes. Using survival and longitudinal transcriptomic data in NKI/SMC (N = 20), treatment-induced increases in Fun-CIM-associated genes and ssGSEA scores were associated with reduced recurrence, whereas Dys-CIM-associated genes and scores were associated with increased recurrence. In multivariable analyses within independent chemotherapy-treated BC cohorts (METABRIC, N = 412; SCAN-B, N = 2,462), higher baseline Fun-CIM ssGSEA scores were associated with better outcomes, whereas higher baseline Dys-CIM ssGSEA scores were associated with worse outcomes. These findings establish CIM as a dynamic, trajectory-level process and position CIMIC as a framework for defining CIM trajectories and supporting future efforts to identify predictors, mechanisms, and therapeutic strategies that maximize beneficial CIM.

cancer biology↗