Loco-regional therapy and breast cancer survival: searching for a link

Extracellular matrix shapes cancer stem cell behavior in breast cancer: a mini review

Today, cancer has become one of the leading global tragedies. It occurs when a small number of cells in the body mutate, causing some of them to evade the body's immune system and proliferate uncontrollably. Even more irritating is the fact that patients with cancers frequently relapse after conventional chemotherapy and radiotherapy, leading to additional suffering. Scientists thereby presume that cancer stem cells (CSCs) are the underlying cause of metastasis and recurrence. In recent years, it was shown that not only can chemotherapy and radiotherapy underperform in the treatment of breast cancer, but they can also increase the number of breast cancer stem cells (BCSCs) that transform regular breast cancer cells into their own population. Such data somewhat support the aforementioned hypothesis. Meanwhile, our understanding of the extracellular matrix (ECM) has changed considerably over the last decade. A lot of studies have bit by bit complemented human knowledge regarding how the ECM greatly shapes the behaviors of BCSCs. In this review, we highlighted the influence on BCSCs exerted by different critical components and biochemical properties of ECM.

Complications and patient-reported outcomes after radiotherapy in breast cancer patients undergoing implant-based breast reconstruction: a retrospective study from a large Chinese breast disease center

BACKGROUND

Postmastectomy radiation therapy (PMRT) can influence the outcome of implant-based breast reconstruction (IBBR). This study aims to investigate the complications and patient-reported outcomes (PROs) following PMRT between direct-to-implant (DTI) and tissue expander-to-implant (TEI) reconstruction.

METHODS

The retrospective study included breast cancer patients undergoing IBBR and PMRT. Patients were divided into a permanent implant group (PI-PMRT) and a tissue expander group (TE-PMRT). Complications, reconstruction failure, and reoperation were compared between the two groups. PROs were assessed using the BREAST-Q scale.

RESULTS

A total of 203 patients were included: 99 in the PI-PMRT group and 104 in the TE-PMRT group. The incidence of severe capsular contracture was significantly higher in the PI-PMRT group compared to the TE-PMRT group (37.4% vs. 24.0%, p = 0.039). The PI-PMRT group had a significantly lower rate of reconstruction failure (9.1% vs. 19.2%, p = 0.039) and reoperation (13.1% vs. 24.0%, p = 0.046). Multivariate analysis revealed that the absence of mesh (OR = 2.177, p = 0.040) and DTI reconstruction (OR = 1.922, p = 0.046) were independent predictors of severe capsular contracture; the absence of mesh (OR = 4.699, p = 0.015) and TEI reconstruction (OR = 2.429, p = 0.043) were independent predictors of reconstruction failure. BREAST-Q scores indicated greater breast satisfaction in the PI-PMRT group (p = 0.031).

CONCLUSIONS

Although DTI reconstruction resulted in a higher risk of severe capsular contracture, the higher risk of reconstruction failure and reoperation in patients undergoing TEI reconstruction was even more concerning. Furthermore, patients were more likely to report greater breast satisfaction with DTI reconstruction. Therefore, DTI reconstruction may be a more appropriate option for patients anticipating PMRT.

Locoregional Recurrence Patterns in Patients With Different Molecular Subtypes of Breast Cancer

Importance

While numerous studies have consistently reported that the molecular subtypes of breast cancer (BC) are associated with different patterns of distant metastasis, few studies have investigated the association of tumor subtypes with locoregional recurrence.

Objective

To investigate the patterns of ipsilateral breast tumor recurrence (IBTR), regional recurrence (RR), and contralateral BC (CBC) according to tumor subtypes.

Design, Setting, and Participants

This retrospective cohort study used the clinical records of patients who underwent BC surgery at a single institution in South Korea between January 2000 and December 2018. Data were analyzed from May 1, 2019, to February 20, 2023.

Exposures

Ipsilateral breast tumor recurrence, RR, and CBC events.

Main Outcomes and Measures

The primary outcome was differences in annual incidence patterns of IBTR, RR, and CBC according to tumor subtypes. Hormone receptor (HR) status was assessed by immunohistochemical staining assay, and ERBB2 status was evaluated according to American Society of Clinical Oncology and College of American Pathologists guidelines.

Results

A total of 16 462 female patients were included in the analysis (median age at time of operation, 49.0 years [IQR, 43.0-57.0 years]). The 10-year IBTR-, RR-, and CBC-free survival rates were 95.9%, 96.1%, and 96.5%, respectively. On univariate analysis, HR-/ERBB2+ tumors had the worst IBTR-free survival (vs HR+/ERBB2- subtype: adjusted hazard ratio, 2.95; 95% CI, 2.15-4.06), while the HR-/ERBB2- subtype had the worst RR- and CBC-free survival among all subtypes (vs HR+/ERBB2- subtype, RR: adjusted hazard ratio, 2.95; 95% CI, 2.37-3.67; CBC: adjusted hazard ratio, 2.12; 95% CI, 1.64-2.75). Subtype remained significantly associated with recurrence events in Cox proportional hazards regression analysis. Regarding the annual recurrence pattern, the IBTR patterns of HR-/ERBB2+ and HR-/ERBB2- subtypes showed double peaks, while HR+/ERBB2- tumors showed a steadily increasing pattern without distinguishable peaks. Additionally, the HR+/ERBB2- subtype seemed to have a steady RR pattern, but other subtypes showed the highest RR incidence at 1 year following surgery, which then gradually decreased. The annual recurrence incidence of CBC gradually increased among all subtypes, and patients with the HR-/ERBB2- subtype had a higher incidence than patients with other subtypes over 10 years. Younger patients (age ≤40 years) had greater differences in IBTR, RR, and CBC patterns between subtypes than did older patients.

Conclusions and Relevance

In this study, locoregional recurrence occurred with different patterns according to BC subtypes, with younger patients having greater differences in patterns among subtypes than older patients. The findings suggest that tailoring surveillance should be recommended regarding differences in locoregional recurrence patterns according to tumor subtypes, particularly for younger patients.

Antitumor action of a novel histone deacetylase inhibitor, YF479, in breast cancer

Accumulating evidence demonstrates important roles for histone deacetylase in tumorigenesis (HDACs), highlighting them as attractive targets for antitumor drug development. Histone deactylase inhibitors (HDACIs), which have shown favorable anti-tumor activity with low toxicity in clinical investigations, are a promising class of anticancer therapeutics. Here, we screened our compound library to explore small molecules that possess anti-HDAC activity and identified a novel HDACI, YF479. Suberoylanilide hydroxamic acid (SAHA), which was the first approved HDAC inhibitor for clinical treatment by the FDA, was as positive control in our experiments. We further demonstrated YF479 abated cell viability, suppressed colony formation and tumor cell motility in vitro. To investigate YF479 with superior pharmacodynamic properties, we developed spontaneous and experimental breast cancer animal models. Our results showed YF479 significantly inhibited breast tumor growth and metastasis in vivo. Further study indicated YF479 suppressed both early and end stages of metastatic progression. Subsequent adjuvant chemotherapy animal experiment revealed the elimination of local-regional recurrence (LRR) and distant metastasis by YF479. More important, YF479 remarkably prolonged the survival of tumor-bearing mice. Intriguingly, YF479 displayed more potent anti-tumor activity in vitro and in vivo compared with SAHA. Together, our results suggest that YF479, a novel HDACI, inhibits breast tumor growth, metastasis and recurrence. In light of these results, YF479 may be an effective therapeutic option in clinical trials for patients burdened by breast cancer.