Co-expression effect of LLGL2 and SLC7A5 to predict prognosis in ERα-positive breast cancer.

Lethal giant larvae homolog 2 (LLGL2) and solute carrier family 7 member 5 (SLC7A5) have been reported to be involved in resistance to endocrine therapy. This study aimed to assess the effects of LLGL2/SLC7A5 co-expression in predicting prognosis and response to tamoxifen therapy in ERα-positive breast cancer patients according to LLGL2/SLC7A5 mRNA and protein expression in long-term follow-up invasive breast cancer tissues. We identified that low LLGL2/SLC7A5 mRNA co-expression (LLGL2low/SLC7A5low) was associated with disease-free survival (DFS) compared with other combination groups in all breast cancer patients. In ERα-positive breast cancer patients, LLGL2low/SLC7A5low showed longer DFS and overall survival (OS) compared with LLGL2high/SLC7A5high and a positive trend of longer survival compared with the other combination groups. We also observed that LLGL2low/SLC7A5low showed longer survival compared with LLGL2high/SLC7A5high in ERα-positive breast cancer patients receiving adjuvant tamoxifen therapy. Multivariate analysis demonstrated that LLGL2low/SLC7A5low was an independent favorable prognostic factor of both DFS and OS, not only in all breast cancer patients, but also in ERα-positive breast cancer patients. High co-expression of LLGL2 and SLC7A5 protein showed a positive trend of shorter survival. Our study showed that co-expression of LLGL2 and SLC7A5 mRNA is a promising candidate biomarker in early breast cancer patients.

Discovering novel mechanisms of taxane resistance in human breast cancer by whole-exome sequencing.

Taxanes are important drugs used in the treatment of breast cancer; however, some cancer types are taxane-resistant. The aim of the present study was to investigate the underlying mechanisms of taxane resistance using whole-exome sequencing (WES). Six patients with breast cancer whose tumors responded well to anthracycline treatment but grew rapidly during neoadjuvant taxane-based chemotherapy, were included in the present study. WES of samples from these patients was carried out to identify somatic mutations of candidate genes thought to affect taxane resistance, and the candidate proteins were structurally modeled. The mRNA and protein expression levels of these candidate genes in other breast cancers treated with taxanes were also examined. Nine variants common to all six patients were identified and two of these [R552P in V-type proton ATPase catalytic subunit A (ATP6V1A) and T114P in apolipoprotein B MRNA editing enzyme catalytic subunit 3F (APOBEC3F)] were selected. The results also showed that, protein-structure visualization suggested that these mutations may cause structural changes. The Kaplan-Meier analyses revealed that higher APT6V1A and APOBEC3F expression levels were significantly associated with poorer disease-free survival (DFS) and overall survival. Moreover, multivariate analysis identified high ATP6V1A mRNA expression as an independent risk factor for poor DFS. Two specific mutations that might affect taxane resistance were identified. Thus, these results suggest that breast cancer patients receiving taxanes who have high ATP6V1A or APOBEC3F expression levels may have shorter survival.

Predictive factors for patients who need treatment for chronic post-surgical pain (CPSP) after breast cancer surgery.

BACKGROUND: Although chronic postsurgical pain (CPSP) after breast cancer surgery is a common and prevalent postsurgical adverse event, the need for CPSP treatment has not been investigated. This study examined the proportion of patients who needed treatment for CPSP and associated predictors. METHODS: We conducted a cross-sectional study with female patients who underwent breast cancer surgery at our institution. Participants were aged ≤ 65 years at the time of this study and were at least 1 year post surgery. The questionnaire examined the presence of and need for treatment for CPSP and included the Japanese version of the Concerns about Recurrence Scale (CARS-J). Multivariate analyses were used to identify independent predictors of needing treatment for CPSP. RESULTS: In total, 305 patients completed the questionnaire. The mean time since surgery was 67.1 months; 156 (51%) patients developed CPSP after breast cancer surgery and 61 (39%) needed treatment for CPSP. Among patients that developed CPSP, the fear of breast cancer recurrence as assessed by the CARS-J (odds ratio [OR] 2.59, 95% confidence interval [CI] 1.14-6.28, P = 0.028) and ≥ 2 postsurgical pain regions (OR 2.52, 95% CI 1.16-5.57, P = 0.020) were independent predictors of needing treatment for CPSP. CONCLUSIONS: This study is the first to identify the proportion and predictors of patients who need treatment for CPSP. Fear of breast cancer recurrence and ≥ 2 postsurgical pain regions may predict the need for CPSP treatment among patients following breast cancer surgery.

Low RAI2 expression is a marker of poor prognosis in breast cancer.

PURPOSE: Retinoic acid-induced 2 (RAI2) has been shown to be a putative suppressor of the early hematogenous dissemination of tumor cells to the bone marrow in breast cancer. Here, we investigated the associations of RAI2 mRNA and protein expression with clinicopathological factors and prognosis in breast cancer patients with long-term follow-up. METHODS: Invasive breast cancer tissues (n = 604) were analyzed for RAI2 mRNA expression. We examined the associations of clinicopathological factors with the expression levels of RAI2 mRNA in these samples. We also analyzed RAI2 protein expression by immunohistochemistry in invasive breast cancer tissues (n = 422). RESULTS: We identified significant positive associations between low expression of RAI2 mRNA and shorter disease-free survival (DFS), breast-cancer-specific survival (BCSS), and overall survival (OS) in breast cancer patients. We also identified significant positive associations between negative for RAI2 protein expression and shorter DFS, BCSS, and OS in breast cancer patients. Low RAI2 mRNA and negative for RAI2 protein expression were positively associated with larger tumor size, higher tumor grade, and ERα-negativity. Multivariate analyses indicated that not only RAI2 mRNA but also RAI2 protein expression were independent risk factors for both DFS and BCSS in breast cancer patients. The median follow-up periods were 10.3 and 9.3 years for the RAI2 mRNA and protein expression analyses, respectively. CONCLUSIONS: Our findings suggest that RAI2 has a role in the metastasis of breast cancer, and that RAI2 expression could be a promising candidate biomarker of prognosis in breast cancer patients.

Sentinel lymph node biopsy may be unnecessary for ductal carcinoma in situ of the breast that is small and diagnosed by preoperative biopsy.

BACKGROUND: Current guidelines do not recommend that sentinel lymph node biopsy is routinely performed for ductal carcinoma in situ; thus, indications for sentinel lymph node biopsy in patients with ductal carcinoma in situ remain controversial. In this study, we investigated whether sentinel lymph node biopsy can be safely omitted when ductal carcinoma in situ has been diagnosed by preoperative biopsy. METHODS: We retrospectively analysed sentinel lymph node metastasis rates and upstaging to invasive cancer in surgical specimens, performed receiver operating characteristic analysis for ductal carcinoma in situ lesion size and assessed correlations with preoperative clinicopathological factors of 277 patients with ductal carcinoma in situ diagnosed by preoperative biopsy at our institution. RESULTS: Among 277 patients with sentinel lymph node biopsy, six (2.2%) had sentinel lymph node metastasis. All six were upstaged to invasive cancer by pathological examination of surgical specimens. In total, 69 patients (24.9%) were upstaged to invasive cancer. The mean size of ductal carcinoma in situ lesions on preoperative imaging was significantly larger for the 69 upstaged patients (50.0 mm) than for the non-upstaged patients (34.4 mm; P < 0.0001). Of the 277 patients with sentinel lymph node biopsy, 117 (42.2%) had preoperative ductal carcinoma in situ lesions <31.8 mm, which was identified as the optimal cut-off size by receiver operating characteristic analysis. Of these 117 patients, 96 (82.1%, 95% confidence interval: 73.9-88.5%) could be safely omitted from sentinel lymph node biopsy because all of them remained as ductal carcinoma in situ and had negative sentinel lymph nodes at surgery. CONCLUSIONS: Size of ductal carcinoma in situ lesions on preoperative diagnostic imaging is a predictor of diagnosis of invasive cancer on pathological examination of surgical specimens. Sentinel lymph node biopsy may be unnecessary in ductal carcinoma in situ diagnosed by preoperative biopsy in patients with small lesions.