Association of L-type amino acid transporter 1 (LAT1) with the immune system and prognosis in invasive breast cancer.

L-type amino acid transporter 1 (LAT1), also referred to as SLC7A5, is believed to regulate tumor metabolism and be associated with tumor proliferation. In invasive breast cancer, we clinicopathologically investigated the utility of LAT1 expression. LAT1 expression was evaluated via immunohistochemistry analyses in 250 breast cancer patients undergoing long-term follow-up. We assessed the relationships between LAT1 expression and patient outcomes and clinicopathological factors. Breast cancer-specific survival stratified by LAT1 expression was assessed. Human epidermal growth factor receptor 2 (HER2)-positive patients with metastasis received trastuzumab therapy. The density of tumor-infiltrating lymphocytes (TILs) was evaluated according to the International Working Group guidelines. In the current study, high LAT1 expression was significantly correlated with estrogen receptor (ER) negativity, progesterone receptor negativity, high histological grade, increased TILs, and programmed death ligand 1 positivity. Among the ER-positive and HER2-negative patients, high LAT1 was an independent indicator of poor outcomes (hazard ratio (HR) = 2.97; 95% confidence interval (CI), 1.16-7.62; p = 0.023). Moreover, high LAT1 expression was an independent poor prognostic factor in luminal B-like breast cancer with aggressive features (HR = 3.39; 95% CI 1.35-8.52; p = 0.0094). In conclusion, high LAT1 expression could be used to identify a subgroup of invasive breast cancer characterized by aggressive behavior and high tumor immunoreaction. Our findings suggest that LAT1 might be a candidate therapeutic target for breast cancer patients, particularly those with luminal B-like type breast cancer.

Mutation profiling of uterine cervical cancer patients treated with definitive radiotherapy.

OBJECTIVE: To elucidate tumor mutation profiles associated with outcomes of uterine cervical cancer (UCC) patients treated with definitive radiotherapy. METHODS: Ninety-eight patients with newly diagnosed and pathologically confirmed UCC (82 squamous cell carcinomas, 12 adenocarcinomas, and four adenosquamous carcinomas) who were treated with definitive radiotherapy were analyzed. DNA was extracted from pre-treatment tumor biopsy specimens. The exons of 409 cancer-related genes were sequenced using a next-generation sequencer. Genetic mutations were identified and analyzed for correlations with clinical outcome. RESULTS: Recurrent mutations were observed in PIK3CA (35.7%), ARID1A (25.5%), NOTCH1 (19.4%), FGFR3 (16.3%), FBXW7 (19.4%), TP53 (13.3%), EP300 (12.2%), and FGFR4 (10.2%). The prevalence of mutations in FGFR family genes (i.e., FGFR1-4) was almost as high (24.5%) as that in PIK3CA and ARID1A, both of which are well-studied drivers of UCC. Fifty-five percent (21 of 38) of the identified FGFR mutations were located in the FGFR protein tyrosine kinase domain. Five-year progression-free survival (PFS) rates for FGFR mutation-positive patients (n = 24) were significantly worse than those for FGFR mutation-negative patients (n = 74) (43.9% vs. 68.5%, respectively; P = 0.010). Multivariate analysis identified FGFR mutations as significant predictors of worse 5 year PFS (P = 0.005), independent of clinicopathological variables. CONCLUSIONS: FGFR mutations are associated with worse PFS in UCC patients treated with definitive radiotherapy. These results warrant further validation in prospective studies.

Leptomeningeal metastasis of uterine cervical cancer 17 years after primary tumor treatment.

Leptomeningeal metastasis (LM) of uterine cervical cancer is extremely rare. A 54-year-old woman with uterine cervical cancer treated with surgery and radiotherapy developed LM manifesting as ptosis 17 years later. Although rare, LM should be considered in patients with a history of uterine cervical cancer presenting with cranial nerve symptoms.

Protein expression, gene amplification, and mutational analysis of EGFR in triple-negative breast cancer.

BACKGROUND: Although triple-negative breast cancer (TNBC) with epidermal growth factor receptor (EGFR) expression has been extensively studied, few studies have simultaneously examined EGFR expression and EGFR gene amplification. Here, we examined the correlations of EGFR expression with EGFR gene amplification, EGFR-activating mutations, and the expression of components of the Akt pathway. METHODS: Tumor tissues were obtained from 84 patients with TNBC. We analyzed the expression of EGFR, phosphorylated Akt (p-Akt), phosphorylated mammalian target of rapamycin (p-mTOR), and other relevant proteins using immunohistochemistry. We also analyzed EGFR gene and chromosome 7 copy numbers by dual-color in situ hybridization. DNA was extracted from formalin-fixed paraffin-embedded samples. Analysis of EGFR gene-activating mutations was performed using the smart amplification process version 2 assay. RESULTS: Most TNBCs expressing EGFR are non-specialized invasive ductal carcinomas, whereas others are likely to be rare specialized carcinomas, such as typical medullary carcinoma, apocrine carcinoma, metaplastic carcinoma, and adenoid cystic carcinoma. EGFR was expressed in samples from 28 of 84 (33.3%) patients, but the EGFR gene was not amplified in any of the 84 samples. There were significant correlations between EGFR expression and the number of polysomic cells and the presence of high polysomy of chromosome 7. However, EGFR expression was not correlated with p-Akt or p-mTOR expression, nor with the other clinicopathological factors recorded in this study. We found no evidence of EGFR gene-activating mutations. CONCLUSIONS: EGFR gene amplification and EGFR-activating mutations might not be the mechanisms leading to the constitutive activation of EGFR in TNBC. Further investigation is needed to clarify the other molecular mechanisms for oncogenic activation of EGFR in TNBC.

Correlation of L-type amino acid transporter 1 and CD98 expression with triple negative breast cancer prognosis.

Triple negative breast cancer (TNBC) is a heterogeneous, aggressive cancer for which there is no effective chemotherapy or targeted therapy. We aimed to evaluate L-type amino acid transporter (LAT) 1 and CD98 expression immunohistochemically in patients with breast cancer, especially TNBC. Out of 129 patients, LAT1 was positive in 56 patients (43.4%), and CD98 was positive in 41 patients (31.8%). The positive ratio of LAT1 expression in luminal A cases was 7.9%, 30.0% in luminal B cases, 71.4% in HER2 cases and 64.0% in TN cases. HER2 and TN subtypes expressed LAT1 and CD98 at higher levels than luminal A and B subtypes (both P < 0.001). LAT1 and CD98 expression correlated with tumor size (LAT1, P = 0.010; CD98, P = 0.007), nuclear grade (LAT1, P < 0.001; CD98, P < 0.001) and Ki67 labeling index (LAT1, P < 0.001; CD98, P = 0.001). LAT1 and CD98 expression was negatively associated with ER and PgR (both P < 0.001). In TNBC, the 5-year disease-free rate of CD98+ (63.6%) or LAT1+/CD98+ (61.9%) patients was significantly worse than that of CD98- (89.3%) patients or those with no co-expression of LAT1 and CD98 (89.7%), respectively (P = 0.014, P = 0.009). The 5-year survival rates of CD98 positive/negative patients were 77.3% and 100% (P = 0.050), respectively, whereas that of patients with LAT1+/CD98+ (76.2%) was significantly worse (100%) (P = 0.040). Multivariate analysis confirmed that CD98+ or LAT1+/CD98+ expression were risk factors for relapse in TNBC (P = 0.023, P = 0.019). Thus, in the present study we show that LAT1 and CD98 expression are prognostic factors. Inhibition of these proteins might provide a new therapeutic strategy in TNBC.