Exploiting Therapy-Induced Senescence for Enhanced Cancer Immunotherapy: Strategic Combinations and Translational Considerations

An emerging translational strategy in cancer therapy is the induce-then-purge approach: inducing senescence to prime immune recognition, followed by eradicating residual senescent cells with senolytics (or by recruiting immune effectors). This aims to prevent SASP-driven tumor relapse. Preclinical models utilizing BCL-2/BCL-xL inhibitors (e.g., navitoclax ) demonstrate selective clearance of therapy-induced senescent (TIS) cells, reduction of pro-tumorigenic Senescence-Associated Secretory Phenotype (SASP) factors, and improved responses when senolytics are sequenced after senescence-inducing therapy.

These data provide a rationale for combining senescence induction + Immune Checkpoint Inhibitors (ICI) with either concurrent or sequential senolytic therapy. The dual goal is to (a) maximize immune-mediated clearance and (b) avoid long-term SASP-mediated immune suppression or tumor promotion. Several early-phase clinical studies are evaluating navitoclax and other BCL-2 family inhibitors in cancer patients, with safety, tolerability, and pharmacokinetic (PK) profiles as primary endpoints. Translational arms of these trials are beginning to measure senescence and immune biomarkers to inform future combinatorial designs [118, 119].

Clinical evidence to date is encouraging but mixed, highlighting critical variables that determine outcome: tumor type, the agent used to trigger senescence, timing/sequence relative to ICI, and the molecular profile of the SASP. Across reviews and translational reports, positive signals tend to cluster where senescence induction robustly increases antigen presentation and T-cell recruitment without prolonged SASP-mediated myeloid immunosuppression. Conversely, models and early clinical observations warn that chronic accumulation of senescent cells can induce immunosuppressive myeloid populations and upregulate immune checkpoints, potentially increasing immune-related adverse effects or limiting long-term benefit if senescent cells are not cleared.

These insights motivate trial designs that incorporate serial immune and senescence biomarkers (e.g., p16/p21, SASP cytokines, MHC expression, PD-L1 glycosylation status) and test distinct sequencing strategies (concurrent vs. induction-then-ICI vs. induction-then-senolytic) [120, 121]. In sum, reported data support a strategy in which TIS is used to convert “cold” tumors into an immunologically inflamed state that is then exploited with immune checkpoint or adoptive therapies, while senolytics or immune clearance are deployed to remove persistent senescent cells and forestall SASP-driven relapse.

The most compelling translational next steps—already underway in several trial consortia—are: (1) biomarker-led patient selection, (2) carefully timed sequencing to preserve effector T-cell function, and (3) integrated correlative studies to define which senescent signatures predict durable responses versus those that predict immunosuppression or toxicity.

Potential Combination Strategies of Therapy-Induced Senescence, Immunotherapies, and Senolytics