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Gene & Protein in Disease Prognostic role of SIRT1 expression in cancer

A B

Figure 4. Depiction of publication bias. (A) The funnel plot shows the concentration of individual studies with larger SE near the base around the midline
symmetrically. (B) The bubble plot illustrates the asymmetrical distribution of studies relative to the middle regression line, with respect to the standard
error of the effect size for each study.
Abbreviation: SE: Standard errors.

intercept (coefficient of the intercept = −1.634, 95% no significant evidence of bias, supporting the robustness
CI [−12.579 – 9.310], P = 0.752) in Egger’s test suggested of the findings, despite some visual asymmetry in the data
that the observed asymmetry in the funnel plot may be presentation.
due to factors other than publication bias. Further analysis The findings of our meta-analysis are consistent with
using trim-and-fill, with no imputed studies, showed several studies. For instance, Jiang et al. investigated
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no change in the effect size (effect size = 1.483 ± 0.2974, the clinical and prognostic value of SIRT1 in gastric
95% CI [0.900 – 2.066], P < 0.001), further supporting cancer and discovered a notable association between high
the robustness of the observed effect size. Overall, these SIRT1 expression and poorer 3-year OS. This finding is
analyses contribute to a more nuanced understanding parallel with our meta-analysis, which also demonstrated
of potential biases in the study, while reinforcing the a significant prognostic effect for SIRT1 across various
reliability of the reported results. cancers. Both studies found correlations between SIRT1
3.5. Quality assessment expression and clinical features, such as patient age, tumor
stage, lymph node involvement, and tumor differentiation,
During quality appraisal process, discrepancies were suggesting a potential role of SIRT1 in influencing
addressed through discussion, with the involvement cancer progression. However, the difference in the
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of corresponding authors when necessary. The results, association with 5-year OS warrants further exploration,
summarized in Table 4, consistently show high assessment as it highlights the complex long-term prognostic role of
scores ranging from 7 to 9 across all studies, indicating SIRT1 and necessitates additional comprehensive research
the overall methodological robustness in addressing the to understand its varying effects over time. Moreover,
research objectives. Sun et al. conducted an extensive meta-analysis and
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4. Discussion established a clear link between increased SIRT1 expression
and adverse cancer outcomes. Their results showed higher
Our meta-analysis focused on the prognostic role of HRs across various survival metrics associated with
SIRT1 in various cancers, predominantly from Asia, elevated SIRT1 expression. Similar to our findings, they
suggesting a strong positive prognostic value for SIRT1 correlated elevated SIRT1 levels with advanced tumor
(pooled HR = 1.483, 95% CI: 0.900 – 2.065). Despite stages and metastasis. Interestingly, Sun et al. emphasized
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2
low variability (I = 0.00), indicating a consistent impact, the influence of ethnic background on the predictive role
meta-regression across various variables confirmed no of SIRT1 in cancer outcomes, particularly in the Asian
significant heterogeneity, reinforcing the stability of population, with a stronger impact observed in China,
SIRT1’s prognostic value. The subgroup analyses support and supported the significance of regional variations in
consistent and significant effects in both Asian and the prognostic impact of SIRT1. Despite differences in the
non-Asian populations, varying by cancer type, sample specific survival metrics assessed, both studies converge
size, age, sex, tumor stage, and SIRT1 expression levels, on the conclusion that SIRT1 plays a crucial role in cancer
with minimal heterogeneity. Publication bias tests revealed progression and metastasis, suggesting that targeting SIRT1

Volume 4 Issue 1 (2025) 8 doi: 10.36922/gpd.4294