Evolutionary histories of breast cancer and related clones.

Recent studies have documented frequent evolution of clones carrying common cancer mutations in apparently normal tissues, which are implicated in cancer development1-3. However, our knowledge is still missing with regard to what additional driver events take place in what order, before one or more of these clones in normal tissues ultimately evolve to cancer. Here, using phylogenetic analyses of multiple microdissected samples from both cancer and non-cancer lesions, we show unique evolutionary histories of breast cancers harbouring der(1;16), a common driver alteration found in roughly 20% of breast cancers. The approximate timing of early evolutionary events was estimated from the mutation rate measured in normal epithelial cells. In der(1;16)(+) cancers, the derivative chromosome was acquired from early puberty to late adolescence, followed by the emergence of a common ancestor by the patient's early 30s, from which both cancer and non-cancer clones evolved. Replacing the pre-existing mammary epithelium in the following years, these clones occupied a large area within the premenopausal breast tissues by the time of cancer diagnosis. Evolution of multiple independent cancer founders from the non-cancer ancestors was common, contributing to intratumour heterogeneity. The number of driver events did not correlate with histology, suggesting the role of local microenvironments and/or epigenetic driver events. A similar evolutionary pattern was also observed in another case evolving from an AKT1-mutated founder. Taken together, our findings provide new insight into how breast cancer evolves.

Optimization of prediction methods for risk assessment of pathogenic germline variants in the Japanese population.

Predicting pathogenic germline variants (PGVs) in breast cancer patients is important for selecting optimal therapeutics and implementing risk reduction strategies. However, PGV risk factors and the performance of prediction methods in the Japanese population remain unclear. We investigated clinicopathological risk factors using the Tyrer-Cuzick (TC) breast cancer risk evaluation tool to predict BRCA PGVs in unselected Japanese breast cancer patients (n = 1,995). Eleven breast cancer susceptibility genes were analyzed using target-capture sequencing in a previous study; the PGV prevalence in BRCA1, BRCA2, and PALB2 was 0.75%, 3.1%, and 0.45%, respectively. Significant associations were found between the presence of BRCA PGVs and early disease onset, number of familial cancer cases (up to third-degree relatives), triple-negative breast cancer patients under the age of 60, and ovarian cancer history (all P < .0001). In total, 816 patients (40.9%) satisfied the National Comprehensive Cancer Network (NCCN) guidelines for recommending multigene testing. The sensitivity and specificity of the NCCN criteria for discriminating PGV carriers from noncarriers were 71.3% and 60.7%, respectively. The TC model showed good discrimination for predicting BRCA PGVs (area under the curve, 0.75; 95% confidence interval, 0.69-0.81). Furthermore, use of the TC model with an optimized cutoff of TC score ≥0.16% in addition to the NCCN guidelines improved the predictive efficiency for high-risk groups (sensitivity, 77.2%; specificity, 54.8%; about 11 genes). Given the influence of ethnic differences on prediction, we consider that further studies are warranted to elucidate the role of environmental and genetic factors for realizing precise prediction.

High-resolution imaging mass spectrometry combined with transcriptomic analysis identified a link between fatty acid composition of phosphatidylinositols and the immune checkpoint pathway at the primary tumour site of breast cancer.

BACKGROUND: The fatty acid (FA) composition of phosphatidylinositols (PIs) is tightly regulated in mammalian tissue since its disruption impairs normal cellular functions. We previously found its significant alteration in breast cancer by using matrix-assisted laser desorption and ionisation imaging mass spectrometry (MALDI-IMS). METHODS: We visualised the histological distribution of PIs containing different FAs in 65 primary breast cancer tissues using MALDI-IMS and investigated its association with clinicopathological features and gene expression profiles. RESULTS: Normal ductal cells (n = 7) predominantly accumulated a PI containing polyunsaturated FA (PI-PUFA), PI(18:0/20:4). PI(18:0/20:4) was replaced by PIs containing monounsaturated FA (PIs-MUFA) in all non-invasive cancer cells (n = 12). While 54% of invasive cancer cells (n = 27) also accumulated PIs-MUFA, 46% of invasive cancer cells (n = 23) accumulated the PIs-PUFA, PI(18:0/20:3) and PI(18:0/20:4). The accumulation of PI(18:0/20:3) was associated with higher incidence of lymph node metastasis and activation of the PD-1-related immune checkpoint pathway. Fatty acid-binding protein 7 was identified as a putative molecule controlling PI composition. CONCLUSIONS: MALDI-IMS identified PI composition associated with invasion and nodal metastasis of breast cancer. The accumulation of PI(18:0/20:3) could affect the PD-1-related immune checkpoint pathway, although its precise mechanism should be further validated.

Understanding factors related to healthcare avoidance for menstrual disorders and menopausal symptoms: A cross-sectional study among women in Japan.

This study explored the factors associated with healthcare avoidance behavior for menstrual disorders and menopausal symptoms among women in Japan. Using data from a nationally representative cross-sectional online survey conducted in September 2022, responses from 4,950 women aged 25-59 were analyzed. This study applied binomial logistic regression models specifically to participants who reported having ever felt the need to seek healthcare assistance due to health issues related to menstruation and menopause. We computed adjusted odds ratios for key sociodemographic traits, work environment factors, health literacy, menstrual and menopausal symptoms, and attitudes and understanding regarding women's health, associated with healthcare avoidance behavior in the past 12 months. As a sensitivity analysis, a regression was performed limited to those who are working. The results showed that 50.6% of respondents recognized the need for healthcare support for menstrual or menopausal health issues, but 22.8% exhibited healthcare avoidance in the past year. Younger and high-income individuals showed higher avoidance rates. Those with diagnosed gynecological conditions and those perceiving menstrual pain as something to endure also displayed increased avoidance tendencies. Women experiencing significant health effects beyond work and those lacking understanding of the purpose of health check-ups were more prone to healthcare avoidance. Our results underscore the importance of implementing strategically tailored health education initiatives, and re-examining societal attitudes concerning women's health, in order to cultivate enhanced healthcare-seeking behaviors among women.

Lack of impact of the ALDH2 rs671 variant on breast cancer development in Japanese BRCA1/2-mutation carriers.

The aldehyde degrading function of the ALDH2 enzyme is impaired by Glu504Lys polymorphisms (rs671, termed A allele), which causes alcohol flushing in east Asians, and elevates the risk of esophageal cancer among habitual drinkers. Recent studies suggested that the ALDH2 variant may lead to higher levels of DNA damage caused by endogenously generated aldehydes. This can be a threat to genome stability and/or cell viability in a synthetic manner in DNA repair-defective settings such as Fanconi anemia (FA). FA is an inherited bone marrow failure syndrome caused by defects in any one of so far identified 22 FANC genes including hereditary breast and ovarian cancer (HBOC) genes BRCA1 and BRCA2. We have previously reported that the progression of FA phenotypes is accelerated with the ALDH2 rs671 genotype. Individuals with HBOC are heterozygously mutated in either BRCA1 or BRCA2, and the cancer-initiating cells in these patients usually undergo loss of the wild-type BRCA1/2 allele, leading to homologous recombination defects. Therefore, we hypothesized that the ALDH2 genotypes may impact breast cancer development in BRCA1/2 mutant carriers. We genotyped ALDH2 in 103 HBOC patients recruited from multiple cancer centers in Japan. However, we were not able to detect any significant differences in clinical stages, histopathological classification, or age at clinical diagnosis across the ALDH2 genotypes. Unlike the effects in hematopoietic cells of FA, our current data suggest that there is no impact of the loss of ALDH2 function in cancer initiation and development in breast epithelium of HBOC patients.

[Usefulness of antimycotic agents (itraconazole) in chemotherapy-induced mucositis of breast cancer patients].

Chemotherapy-induced oral mucositis is a common adverse event in breast cancer patients. Breakdown of the mucosal barrier predisposes the patient to bacterial, fungal and viral superinfection, especially candidiasis. We demonstrated the frequency of chemotherapy-induced oral mucositis and oral candidiasis, and the efficacy of antimycotic agents in breast cancer patients. We investigated 32 patients with advanced and metastatic breast cancer who underwent chemotherapy in our department from March, 2009 to August, 2010. The chemotherapy regimens were as follows: FEC (epirubicin/5-FU/cyclophosphamide) followed by taxanes: 21, FEC: 1, TC (docetaxel/cyclophosphamide): 7, DOC (docetaxel): 3, and CPT-11/S-1: 1. Patients had blood and bacteria tests of the oral cavity at the time mucositis symptoms appeared. We administered an antimycotic agent (itraconazole) and evaluated its effect on mucositis at the time mucositis symptoms appeared. 56. 3% of patients had chemotherapy-induced oral mucositis, and 38. 9% of the mucositis patients had oral candidiasis. The incidence of mucositis increased when severe neutropenia occurred. 92. 9% of mucositis patients were cured or improved by itraconazole. In conclusion, chemotherapy caused oral candidiasis in 40% of cases with oral mucositis, and in about 56% of breast cancer patients. The antimycotic agent may be useful for chemotherapy-induced oral mucositis in breast cancer patients.

Genetic and clinical landscape of breast cancers with germline BRCA1/2 variants.

The genetic and clinical characteristics of breast tumors with germline variants, including their association with biallelic inactivation through loss-of-heterozygosity (LOH) and second somatic mutations, remain elusive. We analyzed germline variants of 11 breast cancer susceptibility genes for 1,995 Japanese breast cancer patients, and identified 101 (5.1%) pathogenic variants, including 62 BRCA2 and 15 BRCA1 mutations. Genetic analysis of 64 BRCA1/2-mutated tumors including TCGA dataset tumors, revealed an association of biallelic inactivation with more extensive deletions, copy neutral LOH, gain with LOH and younger onset. Strikingly, TP53 and RB1 mutations were frequently observed in BRCA1- (94%) and BRCA2- (9.7%) mutated tumors with biallelic inactivation. Inactivation of TP53 and RB1 together with BRCA1 and BRCA2, respectively, involved LOH of chromosomes 17 and 13. Notably, BRCA1/2 tumors without biallelic inactivation were indistinguishable from those without germline variants. Our study highlights the heterogeneity and unique clonal selection pattern in breast cancers with germline variants.

Pattern of RECK CpG methylation as a potential marker for predicting breast cancer prognosis and drug-sensitivity.

The membrane-anchored glycoprotein RECK negatively regulates multiple metalloproteinases and is frequently downregulated in tumors. Forced RECK expression in cancer cells results in suppression of tumor angiogenesis, invasion, and metastasis in xenograft models. A previous methylome study on breast cancer tissues detected inverse correlation between RECK CpG methylation (in an intron-1 region) and relapse-free survival. In this study, we focused on another region of the RECK CpG island (a promoter/exon-1 region) and found an inverse correlation between its methylation and RECK-inducibility by an HDAC inhibitor, MS275, among a panel of breast cancer cell lines (n=15). In clinical samples (n=62), RECK intron-1 methylation was prevalent among luminal breast cancers as reported previously (26 of 38 cases; 68%) and particularly enriched in tumors of the ER+PR- subclass (10 of 10 cases) and of higher histological grades (Grade 2 and 3; 28 of 43 cases; P=0.006). In about a half of these cases, promoter/exon-1 methylation was absent, and hence, RECK may be inducible by certain drugs such as MS275. Our results indicate the value of combined use of two RECK methylation markers for predicting prognosis and drug-sensitivity of breast cancers.

Assessing the effects of neoadjuvant chemotherapy on lymphatic pathways to sentinel lymph nodes in cases of breast cancer: Usefulness of the indocyanine green-fluorescence method.

BACKGROUNDS: It is not clear how lymphatic pathways to the sentinel lymph node (SLN) change during neoadjuvant chemotherapy (NAC) for breast cancer. METHODS: Using the indocyanine green (ICG)-fluorescence method, we compared lymphatic pathways to the SLN (sentinel lymphatic pathways) and SLN location before and after NAC in 36 patients (38 breasts). RESULTS: Despite that 42.8% of the sentinel lymphatic pathways were changed by NAC, the locations of the SLNs were not affected by NAC. CONCLUSION: These results suggest that the true SLN can be detected even after NAC, and that SLNB can be performed after NAC for clinically node-negative patients.

IgG4-related autoimmune pancreatitis involving the colonic mucosa.

We report a case of autoimmune pancreatitis involving the colonic mucosa. Although serum level of IgG4 was normal, computed tomography and endoscopic retrograde cholangiopancreatography showed diffuse enlargement of the pancreas and irregular narrowing of the pancreatic ducts, respectively. Colonoscopy revealed a polypoidal lesion in the ascending colon. A lymphoplasmacytic infiltration was seen both in the pancreas and in the polypoidal lesion of the colon. Furthermore, immunohistochemical analysis showed abundant IgG4-positive plasma cells in these lesions. This is the first case report of a simultaneous occurrence of autoimmune pancreatitis and a colonic polypoidal lesion, both of which are characterized with increased IgG4 responses.