Update on the Use of Molecular Subtyping in Breast Cancer

Acyl-CoA Thioesterase 8 (ACOT8) is a Poor Prognostic Biomarker in Breast Cancer

Purpose

This study aimed to investigate the expression of Acyl-CoA thioesterase 8 (ACOT8) in breast cancer (BC) and its association with clinicopathological characteristics, patient survival, and immune infiltration.

Methods

We conducted a comprehensive analysis of ACOT8 mRNA differential expression across various cancer types, followed by survival analysis. We focused on BC, where ACOT8 expression was evaluated at both the mRNA and protein levels using online databases, qRT-PCR, and immunohistochemistry. Associations between ACOT8 expression and clinicopathological parameters were assessed using different databases. Additionally, we investigated the prognostic significance of ACOT8 in BC patients by analyzing various cohorts and databases. Furthermore, we predicted a potential signaling pathway and identified miR-1-3p as a possible upstream regulator of ACOT8. Finally, the relationship between ACOT8 and immune system infiltration, as well as immune checkpoint molecules, was examined.

Results

Our findings demonstrated upregulated ACOT8 mRNA and protein levels in BC. Elevated ACOT8 expression correlated positively with various clinicopathological characteristics, indicating an unfavorable prognosis for patients. Functional enrichment analysis suggested ACOT8 involvement in lipid metabolism, mitochondrial components, and ribosomal functions. Moreover, we identified connections between ACOT8 and immune system markers, immune cell infiltration, and immune checkpoints.

Conclusion

This study provides compelling evidence for ACOT8 upregulation in BC and its association with clinicopathological features and patient outcomes. Additionally, our findings suggest that targeting ACOT8 and immune checkpoints might enhance the effectiveness of immunotherapy in BC patients.

The prognostic analysis of further axillary dissection in breast cancer with 1-2 positive sentinel lymph nodes undergoing mastectomy

Background

The ACOSOG Z0011 study has shown that axillary lymph node dissection (ALND) is an option to be considered in patients who had 1-2 metastatic sentinel lymph nodes (SLNs) who proceed with breast-conserving along with postoperative radiotherapy. However, there remains controversy regarding the applicability of this approach in patients who had a mastectomy. The aim of our study is to determine the prognostic differences and risk factors associated with the decision to opt for ALND in breast cancer patients who had 1-2 metastatic SLNs who receive a mastectomy.

Methods

The study conducted a retrospective analysis of patients diagnosed with cT1-2N0 breast cancer and treated at The Fourth Hospital of Hebei Medical University between January 2016 and December 2021, and patients were divided into two cohorts according to whether ALND was performed after sentinel lymph node biopsy (SLNB): SLNB cohort and SLNB + ALND cohort. Outcomes included the locoregional recurrence rate (LRR), disease-free survival (DFS), and overall survival (OS). Propensity score matching (PSM) was conducted to ensure the balance of variables between the two cohorts. Cox proportional hazard models were employed to ascertain the univariate and multivariate relative risks associated with survival.

Results

There were 812 cases enrolled. After the PSM, 234 receiving ALND and 234 not receiving ALND were matched. A median follow-up period of 56.72 ± 20.29 months was observed. During that time, no significant difference was identified in the DFS and OS in the SLNB + ALND cohort and the SLNB cohort (P = 0.208 and P = 0.102), except for those under 40 years old, SLNB + ALND group showed a reduction in LRR compared to SLNB group (11.1% vs. 2.12%, P = 0.044). Multivariate Cox analysis showed that younger (≤ 40 years), progesterone receptor (PR)-negative, and SLNB alone were independent risk factors for LRR; perineural invasion was a risk factor, while endocrinotherapy was a beneficial prognostic indicator for DFS and OS among patients with positive hormone receptor.

Conclusion

ALND does not impact DFS and OS in patients with 1-2 metastatic SLNs who have completed a mastectomy. Being younger (≤ 40 years), having a negative PR, and undergoing SLNB alone were independent risk factors for LRR. Given this finding, we recommend avoiding axillary treatment such as ALND or radiotherapy in patients without risk factors.

Lung-heart toxicity in a randomized clinical trial of hypofractionated image guided radiation therapy for breast cancer

Background

TomoBreast hypothesized that hypofractionated 15 fractions/3 weeks image-guided radiation therapy (H-IGRT) can reduce lung-heart toxicity, as compared with normofractionated 25-33 fractions/5-7 weeks conventional radiation therapy (CRT).

Methods

In a single center 123 women with stage I-II operated breast cancer were randomized to receive CRT (N=64) or H-IGRT (N=59). The primary endpoint used a composite four-items measure of the time to 10% alteration in any of patient-reported outcomes, physician clinical evaluation, echocardiography or lung function tests, analyzed by intention-to-treat.

Results

At 12 years median follow-up, overall and disease-free survivals between randomized arms were comparable, while survival time free from alteration significantly improved with H-IGRT which showed a gain of restricted mean survival time of 1.46 years over CRT, P=0.041.

Discussion

The finding establishes TomoBreast as a proof-of-concept that hypofractionated image-guided radiation-therapy can improve the sparing of lung-heart function in breast cancer adjuvant therapy without loss in disease-free survival. Hypofractionation is advantageous, conditional on using an advanced radiation technique. Multicenter validation may be warranted.

Trial registration

https://clinicaltrials.gov/ct2/show/NCT00459628. Registered 12 April 2007.