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Stemness and epithelial-mesenchymal transition (EMT) are two fundamental characteristics of metastasis that are controlled by diverse regulatory factors, including transcription factors. Compared with other subtypes of breast cancer, basal-type or triple-negative breast cancer (TNBC) has high frequencies of tumor relapse. However, the role of alpha-globin transcription factor CP2 (TFCP2) has not been reported as an oncogenic driver in those breast cancers. Here, we show that TFCP2 is a potent factor essential for EMT, stemness, and metastasis in breast cancer. TFCP2 directly bound promoters of EGF and TGFα to regulate their expression and stimulate autocrine signaling via EGFR. These findings indicate that TFCP2 is a new antimetastatic target and reveal a novel regulatory mechanism in which a positive feedback loop comprising EGF/TGFα and AKT can control malignant breast cancer progression. SIGNIFICANCE: TFCP2 is a new antimetastatic target that controls TNBC progression via a positive feedback loop between EGF/TGFα and the AKT signaling axis., (©2020 American Association for Cancer Research.)

Basal type breast cancer is the most aggressive and has mesenchymal features with a high metastatic ability. However, the signaling node that determines the basal type features in breast cancer remains obscure. Here, we report that FYN among SRC family kinases is required for the maintenance of basal type breast cancer subtype. Importantly, FYN enhanced NOTCH2 activation in basal type breast cancer cells through STAT5-mediated upregulation of Jagged-1 and DLL4 NOTCH ligands, thereby contributed to mesenchymal phenotypes. In addition, we found that high levels of FYN persist in basal type breast cancer cells by a positive feedback loop between FYN and STAT5. FYN interacted directly with STAT5 and increased p-STAT5 that further acts as a transcription factor for FYN. Taken together, our findings demonstrate a pivotal role of FYN and its downstream effectors in maintaining the basal type features in breast cancer.

Poor prognosis of breast cancer patients is closely associated with metastasis and relapse. There is substantial evidence supporting that cancer stem-like cells (CSCs) are primarily responsible for relapse in breast cancer after anticancer treatment. However, there is a lack of suitable drugs that target breast cancer stem-like cells (BCSCs). Here, we report that phloroglucinol (PG), a natural phlorotannin component of brown algae, suppresses sphere formation, anchorage-independent colony formation and in vivo tumorigenicity. In line with these observations, treatment with PG also decreased CD44(+) cancer cell population as well as expression of CSC regulators such as Sox2, CD44, Oct4, Notch2 and β-catenin. Also, treatment with PG sensitized breast cancer cells to anticancer drugs such as cisplatin, etoposide, and taxol as well as to ionizing radiation. Importantly, PG inhibited KRAS and its downstream PI3K/AKT and RAF-1/ERK signaling pathways that regulate the maintenance of CSCs. Taken together, our findings implicate PG as a good candidate to target BCSCs and to prevent the disease relapse., (Copyright © 2015 Elsevier Inc. All rights reserved.)

Metastasis of breast cancer is promoted by epithelial-mesenchymal transition (EMT). Emerging evidence suggests that STAT3 is a critical signaling node in EMT and is constitutively activated in many carcinomas, including breast cancer. However, its signaling mechanisms underlying persistent activation of STAT3 associated with EMT remain obscure. Here, we report that PIM2 promotes activation of STAT3 through induction of cytokines. Activation of STAT3 caused an increase in PIM2 expression, implicating a positive feedback loop between PIM2 and STAT3. In agreement, targeting of either PIM2, STAT3 or PIM2-dependent cytokines suppressed EMT-associated migratory and invasive properties through inhibition of ZEB1. Taken together, our findings identify the signaling mechanisms underlying the persistent activation of STAT3 and the oncogenic role of PIM2 in EMT in breast cancer., (© 2015 The Authors. Cancer Science published by Wiley Publishing Asia Pty Ltd on behalf of Japanese Cancer Association.)

Elevated KRAS expression has been frequently associated with cancer progression including breast cancer; however, therapeutic approaches targeting KRAS have been widely unsuccessful and KRAS mutant cancers remain unsolved problem in cancer therapy. In this study, we found that a new 2-pyrone derivative, 5-bromo-3-(3-hydroxyprop-1-ynyl)-2H-pyran-2-one (BHP) can block KRAS-driven breast cancer progression. Importantly, treatment with BHP effectively suppressed the migratory and invasive properties along with epithelial-mesenchymal transition (EMT) in MDA-MB231 breast cancer cells that carry oncogenic KRAS and mesenchymal malignant phenotypes. In parallel, BHP also sensitized the cells to anticancer treatment. Consistently, forced-expression of oncogenic KRAS bestowed the migratory and invasive properties, mesenchymal transition and resistance to anticancer treatment into normal human mammalian breast cells MCF10A and relatively non-malignant MCF7 and SK-BR3 breast cancer cells; however, treatment with BHP blocked those KRAS-induced malignant phenotypes. Notably, BHP interfered the interaction of KRAS with Raf-1 in concentration-dependent manner, thereby blocking the downstream effectors of KRAS signaling that is PI3K/AKT and ERK. Taken together, our findings indicate that the BHP, an α-pyrone derivative, suppresses malignant breast cancer progression by targeting of oncogenic KRAS signaling pathways., (Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.)

We conducted focus groups with women from urban and rural areas in the Nile Delta region to investigate their attitudes regarding breast cancer diagnosis, treatment, and screening. Six 60-min focus groups, each group comprised of 6-10 women with ages between 20-69 years, were conducted. Discussions included breast health, breast cancer diagnosis, treatment, early detection and screening, and communication for breast health. Almost all urban and rural women reported that women do not see physicians until they are seriously ill or have advanced cancer. They reported that oncologists or gynecologists were important to be seen first if a woman suspected breast cancer and primary care physician are not the primary line of cancer diagnosis. Other deterring factors besides distrust in primary care physicians included attitude that breast cancer equals death and lack of knowledge of early detection and screening techniques. Women felt that public education campaigns must be implemented to improve early detection and screening methods for breast cancer. The majority of beliefs regarding breast cancer and screening were common among urban and rural women. Culture-specific and tailored professional and public education programs in developing countries are essential for achieving downstaging cancer.

Objective: To determine the statistics for age, distributions of the type of mammography, ultrasonic evaluation, laterality, assessment category, risk factors, and financial status, amongst females undergoing mammography., Methods: A descriptive review of consecutive records of women undergoing mammography during Janurary and February 2005 at a tertiary care cancer facility, the Shaukat Khanum Memorial Cancer Hospital and Research Center in Lahore, Pakistan., Results: Of a total of 87 patients, only 12 had attended the hospital for mammographic screening. These 12 females could financially afford the cost of their images. The median age of all the females at the time of mammography was 47 years and the mode was 40 years. Of the total, 40 and 32 patients were found in assessment categories 1 and 2 respectively. Only 19 females underwent bilateral mammography whereas forty were evaluated further by ultrasound imaging. Sixteen women had family history of breast cancer among their first degree relatives, twenty eight gave history of Hormone Replacement Therapy and fifty could afford their entire imaging expenses., Conclusion: Most patients received their first mammograms when they already had clearly palpable disease. This was partly be due to economic reasons and mainly because of low level of awareness.