Diffuse large B-cell lymphoma (DLBCL) is the most common and aggressive type of non-Hodgkin lymphoma (NHL) [1]. DLBCL is classified into two major subtypes based on the cell origin and genetic expression: germinal center B-cell-like (GCB) and non-germinal center B-cell-like (non-GCB). The Hans algorithm, based on immunohistochemistry, is widely employed in clinical practice to distinguish between the two subtypes [2]. The standard treatment for DLBCL consists of a combination regimen of rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP). This regimen achieves a cure rate of 60–70%, but approximately 30–40% of patients still experience relapse or remain refractory to therapy [3]. Resistance is more frequently observed in the non-GCB subtype, which is associated with activation of survival pathways and impairment of apoptotic mechanisms [4].

Several molecular alterations have been implicated in the suboptimal therapeutic responses observed in patients with non-GCB DLBCL. Cluster of differentiation 79B (CD79B), a key signaling component of the B-cell receptor (BCR) complex, plays a crucial role in activating the classical nuclear factor kappa B activation (NF-κB) signaling pathway, thereby promoting lymphoma cell survival and proliferation [5].

Autophagy is a tightly regulated cellular recycling process that maintains metabolic homeostasis through lysosomal degradation of damaged organelles and misfolded proteins, typically assessed using markers, including microtubule-associated protein light chain 3 (LC3) and Beclin-1. In lymphoma, autophagy plays a dual context-dependent role, either inhibiting tumor growth or promoting survival under therapeutic stress. Recent evidence has indicated that increased autophagic flux contributes to chemoresistance in DLBCL by enabling tumor cells to evade apoptosis under cytotoxic conditions [6].

Telomerase reverse transcriptase (TERT), the catalytic subunit of telomerase, has emerged as a multifunctional regulator of tumor biology. In addition to its canonical role in telomere elongation, TERT exerts extra-telomeric functions that modulate oncogenic signaling pathways, including NF-κB, protein kinase B (AKT), and myelocytomatosis oncogene (MYC), thereby promoting cell proliferation, survival, and resistance to apoptosis. In B-cell malignancies, TERT contributes to immune evasion and genomic stability while sustaining the constitutive activation of pro-survival transcriptional programs. Elevated TERT expression and promoter mutations have been correlated with poor prognosis and therapeutic resistance in various cancers, indicating their potential involvement in treatment refractoriness [7].

Recent studies have suggested a biological link between BCR signaling, autophagy, and telomerase activity in lymphoma. Activation of BCR through CD79B stimulates key survival pathways such as NF-κB and PI3K/AKT. This activation can also induce autophagy, indicated by increased LC3 expression, which enables tumor cells to adapt to stress [8, 9]. Concurrently, TERT supports cell survival by enhancing mitophagy, a selective form of autophagy, through regulation of PTEN-induced kinase 1 (PINK1) and LC3 [10]. Together, these mechanisms preserve mitochondrial function and may contribute to chemotherapy resistance. Although the interplay between CD79B, LC3, and TERT has not yet been fully explored in non-GCB DLBCL, the overlap of their signaling pathways suggests that they may collectively support tumor progression and diminish treatment response. Therefore, this study aimed to analyze the association between the immunohistochemical (IHC) expression of CD79B, LC3, and TERT and the response to R-CHOP immunochemotherapy in patients with non-GCB DLBCL.

We evaluated CD79B, LC3, and TERT expression in patients with non-GCB DLBCL and their association with R-CHOP response. Although CD79B mutations have been associated with adverse outcomes in previous genomic studies, our findings specifically reflected CD79B protein expression as assessed by IHC. LC3 and TERT expression were significantly common in the non-response group, but were not statistically significant in multivariate analysis. Additionally, TERT and LC3 expressions exhibited a significant positive correlation, indicating coordinated expression.

CD79B expression was significantly associated with non-response to R-CHOP therapy, supporting its role in the pathogenesis of non-GCB DLBCL. CD79B encodes a key immunoreceptor component of the BCR complex, which amplifies BCR signaling and activates downstream NF-κB and PI3K pathways involved in tumor survival. Genetic and molecular profiling studies have demonstrated that CD79B mutations and overexpression are common in activated B-cell-like or non-GCB subtypes, where they frequently co-occur with myeloid differentiation primary response 88 (MYD88) mutations and drive chronic active BCR signaling, contributing to inferior clinical outcomes [14]. Although CD79B mutations have been associated with adverse outcomes in previous genomic studies, our findings specifically reflected CD79B protein expression as assessed by immunohistochemistry. Recent studies have provided additional evidence of this association. CD79B overexpression correlates with R-CHOP response and is a potential target for polatuzumab vedotin therapy [15]. Patients with CD79B mutations have worse overall survival despite standard immunochemotherapy [16]. These findings suggest that CD79B-mediated BCR activation contributes to poor treatment response, consistent with our results.

LC3 expression was more common in the non-response group than in the response group, although the difference was not statistically significant. This suggests a link between increased autophagic activity and reduced sensitivity to R-CHOP. Similar findings were reported by Zhou et al. (2022), who identified an autophagy-related gene signature that predicts survival and treatment resistance in DLBCL. Patients with high autophagy-related gene expression had poor outcomes and increased activation of doxorubicin-resistance and NF-κB pathways [17]. Zhang et al. (2024) also demonstrated that reduced autophagy levels were correlated with shorter progression-free survival in DLBCL, highlighting the importance of balanced autophagic regulation in treatment response [18]. Mandhair et al. (2024) reported subtype-specific autophagic activity in DLBCL, suggesting that autophagy exerts distinct biological roles across different molecular subtypes [19]. These findings suggest a possible association between increased autophagy-related marker expression and treatment response. However, LC3 immunohistochemistry represents a static marker and does not directly reflect autophagic flux. The higher frequency of LC3 positivity in the non-response group aligns with the concept that dysregulated autophagy may enable tumor cells to evade chemotherapy-induced stress, thereby contributing to poor outcomes.

TERT expression was more common in the non-response group than in the response group, suggesting that increased activity may contribute to a poor response to R-CHOP therapy in non-GCB DLBCL. Moreover, TERT maintains telomere length and promotes cellular immortality. In addition, TERT exerts extratelomeric functions, including transcriptional regulation, DNA repair, mitochondrial protection, and modulation of oncogenic signaling pathways, thereby enhancing tumor survival and therapy resistance [7]. Genomic evidence supports the prognostic significance of telomere-related genes (TRGs) in patients with DLBCL. Zhao et al. (2023) demonstrated that higher TRG expression, including that of TERT-associated genes, is linked to poor survival and immune evasion [20]. Lam et al. (2016) demonstrated that TERT activation in B-cell lymphomas occurs primarily through epigenetic or transcriptional mechanisms, rather than through promoter mutations. These results suggest that aberrant TERT activation promotes lymphoma cell survival under chemotherapy-induced stress [21]. However, few studies have specifically assessed TERT protein expression and its functional implications in DLBCL. Future research integrating IHC, molecular, and functional assays is needed to confirm TERT's mechanistic role in DLBCL and its potential as a therapeutic target or predictive biomarker for the R-CHOP response.

TERT expression was positively correlated with LC3 expression (p = 0.002), suggesting a potential interaction between telomerase activity and autophagy, both of which may enhance tumor adaptation to cytotoxic stress. Furthermore, TERT regulates autophagy by modulating LC3 expression. In vascular and endothelial models, Hughes et al. (2021) demonstrated that TERT overexpression increased the conversion of LC3-I to LC3-II, a hallmark of autophagy activation. Inhibition of TERT reduces LC3 conversion and autophagic flux. Autophagy functions downstream of telomerases, forming a coordinated pathway that preserves cellular homeostasis and enhances resistance to oxidative stress [22]. Park et al. (2022) confirmed that TERT activation restores autophagic flux and LC3 processing in human arterioles, demonstrating that telomerase and autophagy work together to maintain nitric oxide–dependent vascular function under stress [23]. The findings support the correlation between TERT and LC3 expression observed in this study. TERT overexpression may potentiate autophagy-mediated survival signaling in DLBCL cells, contributing to non-response to R-CHOP therapy. The significant TERT–LC3 association may indicate a survival mechanism whereby telomerase activation and autophagy cooperate to sustain tumor viability during R-CHOP therapy.

Multivariate analysis identified CD79B as the primary independent marker associated with non-response to R-CHOP therapy, underscoring its key role in mediating resistance via sustained BCR-driven signaling. LC3 and TERT did not emerge as independent predictors, but likely contributed indirectly through metabolic and survival crosstalk, reflecting adaptive mechanisms that support lymphoma cell persistence under cytotoxic stress.

This study offers novel insights into treatment response–related biological processes in non-GCB DLBCL by evaluating CD79B, LC3, and TERT protein expression within the same patient cohort. Our integrated approach highlights the potential interplay between BCR signaling, autophagy-related pathways, and telomerase-associated processes, providing a more comprehensive understanding of the factors associated with the response to R-CHOP therapy. The use of well-characterized samples and standardized IHC evaluations further strengthened the robustness of our findings.

This study had certain limitations. The relatively small sample size may have limited the statistical power, particularly for LC3 and TERT, and may have contributed to the wide CIs in the multivariable analysis. The retrospective, single-center design and intentional sample size–driven selection strategy may have introduced selection bias and limited generalizability. In addition, significant molecular prognostic factors such as double-hit/double-expressor status, MYD88 mutations, and other genetic alterations were not available, raising the possibility of residual confounding. Furthermore, this study evaluated protein expression solely by immunohistochemistry, precluding functional or mechanistic inferences. The absence of survival endpoints analysis further limits the interpretation to associations with the treatment response category. Larger multicenter studies incorporating comprehensive molecular profiling and functional analyses are warranted to elucidate the biological roles of CD79B, LC3, and TERT in non-GCB DLBCL.

CD79B protein expression was independently associated with non-response to R-CHOP therapy in patients with non-GCB DLBCL, underscoring its potential relevance in treatment response–related BCR/NF-κB signaling activity. Although LC3 and TERT expression were not independently associated with treatment outcomes, their positive correlation suggested a possible interplay between autophagy- and telomerase-associated processes in tumor cell survival during chemotherapy. These findings support a multifactorial biological context underlying the treatment response in non-GCB DLBCL and warrant further investigation in larger cohorts and functional studies.