Diverse temporal and spatial mechanisms work, partially through Stanniocalcin-1, V-ATPase and senescence, to activate the extracellular ATP-mediated drug resistance in human cancer cells

Introduction

Resistance to drug therapies is associated with a large majority of cancer-related deaths. ATP-binding cassette (ABC) transporter-mediated drug efflux, epithelial-mesenchymal transition (EMT), cancer stem cells (CSCs), glutathione (GSH), senescence, and vacuole-type ATPase (V-ATPase) all contribute to the resistance. We recently showed that extracellular ATP (eATP) induces and regulates EMT, CSC formation, and ABC transporters in human cancer cells and tumors. eATP also consistently upregulates Stanniocalcin-1 (STC1), a gene that significantly contributes to EMT, CSC formation, and tumor growth. We also found that eATP enhances drug resistance in cancer cells through eATP internalization mediated by macropinocytosis, leading to an elevation of intracellular ATP (iATP) levels, induction of EMT, and CSC formation. However, these factors have never been systematically investigated in the context of eATP-induced drug resistance.

Methods

In this study, we hypothesized that eATP increases drug resistance via inducing ABC efflux, EMT, CSCs, STC1, and their accompanied processes such as GSH reducing activity, senescence, and V-ATPase. RNA sequencing, metabolomics, gene knockdown and knockout, and functional assays were performed to investigate these pathways and processes.

Results and discussion

Our study results showed that, in multiple human cancer lines, eATP induced genes involved in drug resistance, elevated ABC transporters' efflux activity of anticancer drugs; generated transcriptomic and metabolic profiles representing a drug resistant state; upregulated activities of GSH, senescence, and V-ATPase to promote drug resistance. Collectively, these newly found players shed light on the mechanisms of eATP-induced as well as STC1- and V-ATPase-mediated drug resistance and offer potential novel targets for combating drug resistance in cancers.

Clinical Outcomes of Conservative Treatment for Low-Risk Ductal Carcinoma in Situ: A Systematic Review and Pooled Analysis

AIMS

The current gold standard of treatment for ductal carcinoma in situ (DCIS) is surgical resection with or without adjuvant radiotherapy. However, the increased detection and radical treatment of DCIS did not result in a declined incidence of invasive breast cancers, leading to the debate if DCIS has been overtreated. While ongoing randomised controlled trials on active surveillance of DCIS are still in progress, this systematic review aims to evaluate the best evidence on conservative treatment for DCIS from the literature.

MATERIALS AND METHODS

This systematic review was conducted in line with the PRISMA statement. We included all relevant studies published up to June 2022 for analysis. The primary outcomes were overall survival and breast cancer-specific survival (BCSS) of conservative treatment for DCIS.

RESULTS

Three studies, with a total of 34 007 women with low-risk DCIS, were included in the analysis. Active and conservative treatments both resulted in excellent 10-year BCSS, with no statistically insignificant difference (98.6% versus 96.0%, 31 478 women). One study comparing 5-year BCSS of active and conservative treatments only in subjects aged over 80 years also reported [AQ1]an insignificant difference (98.2% versus 96.0%, 2529 women). One study measuring 5- and 10-year overall survival between the treatment groups also reported [AQ1]an insignificant difference (5-year: 96.2% versus 92.4%; 10-year: 85.6% versus 86.7%, 31 106 women).

CONCLUSION

BCSS between active and conservative treatment for women with low-risk DCIS is both excellent and comparable, suggesting that conservative treatment is a possible alternative without compromising survival.

Rare germline alterations of myeloperoxidase predispose to myeloid neoplasms

Myeloperoxidase (MPO) gene alterations with variable clinical penetrance have been found in hereditary MPO deficiency, but their leukemia association in patients and carriers has not been established. Germline MPO alterations were found to be significantly enriched in myeloid neoplasms: 28 pathogenic/likely pathogenic variants were identified in 100 patients. The most common alterations were c.2031-2 A > C, R569W, M519fs* and Y173C accounting for about half of the cases. While functional experiments showed that the marrow stem cell pool of Mpo^-/- mice was not increased, using competitive repopulation demonstrated that Mpo^-/- grafts gained growth advantage over MPO wild type cells. This finding also correlated with increased clonogenic potential after serial replating in the setting of H₂O₂-induced oxidative stress. Furthermore, we demonstrated that H₂O₂-induced DNA damage and activation of error-prone DNA repair may result in secondary genetic damage potentially predisposing to leukemia leukemic evolution. In conclusion, our study for the first time demonstrates that germline MPO variants may constitute risk alleles for MN evolution.

Cancer stem cells, epithelial-mesenchymal transition, ATP and their roles in drug resistance in cancer

The cancer stem cell (CSC) state and epithelial-mesenchymal transition (EMT) activation are tightly interconnected. Cancer cells that acquire the EMT/CSC phenotype are equipped with adaptive metabolic changes to maintain low reactive oxygen species levels and stemness, enhanced drug transporters, anti-apoptotic machinery and DNA repair system. Factors present in the tumor microenvironment such as hypoxia and the communication with non-cancer stromal cells also promote cancer cells to enter the EMT/CSC state and display related resistance. ATP, particularly the high levels of intratumoral extracellular ATP functioning through both signaling pathways and ATP internalization, induces and regulates EMT and CSC. The three of them work together to enhance drug resistance. New findings in each of these factors will help us explore deeper into mechanisms of drug resistance and suggest new resistance-associated markers and therapeutic targets.

Autism-linked gene FoxP1 selectively regulates the cultural transmission of learned vocalizations

Autism spectrum disorders (ASDs) are characterized by impaired learning of social skills and language. Memories of how parents and other social models behave are used to guide behavioral learning. How ASD-linked genes affect the intertwined aspects of observational learning and behavioral imitation is not known. Here, we examine how disrupted expression of the ASD gene FOXP1, which causes severe impairments in speech and language learning, affects the cultural transmission of birdsong between adult and juvenile zebra finches. FoxP1 is widely expressed in striatal-projecting forebrain mirror neurons. Knockdown of FoxP1 in this circuit prevents juvenile birds from forming memories of an adult song model but does not interrupt learning how to vocally imitate a previously memorized song. This selective learning deficit is associated with potent disruptions to experience-dependent structural and synaptic plasticity in mirror neurons. Thus, FoxP1 regulates the ability to form memories essential to the cultural transmission of behavior.

Clinical outcomes of patients with ductal carcinoma in situ in Hong Kong: 10-year territory-wide cancer registry study

BACKGROUND

Incidence of ductal carcinoma in situ (DCIS) has increased in recent decades because of breast cancer screening. This study comprised a long-term survival analysis of DCIS using 10-year territory-wide data from the Hong Kong Cancer Registry.

METHODS

This study included all patients diagnosed with DCIS in Hong Kong from 1997 to 2006. Exclusion criteria were age <30 years or ≥70 years, lobular carcinoma in situ, Paget's disease, and co-existing invasive carcinoma. Patients were stratified into those diagnosed from 1997 to 2001 and those diagnosed from 2002 to 2006. The 5- and 10-year breast cancer-specific survival rates were evaluated; standardised mortality ratios were calculated.

RESULTS

Among the 1391 patients in this study, 449 were diagnosed from 1997 to 2001, and 942 were diagnosed from 2002 to 2006. The mean age at diagnosis was 49.2±9.2 years. Overall, 51.2% of patients underwent mastectomy and 29.5% received adjuvant radiotherapy. The median follow-up interval was 11.6 years; overall breast cancer-specific mortality rates were 0.3% and 0.9% after 5 and 10 years of follow-up, respectively. In total, 109 patients (7.8%) developed invasive breast cancer after a considerable delay. Invasive breast cancer rates were comparable between patients diagnosed from 1997 to 2001 (n=37, 8.2%) and those diagnosed from 2002 to 2006 (n=72, 7.6%).

CONCLUSION

Despite excellent long-term survival among patients with DCIS, these patients were more likely to die of breast cancer, compared with the general population of women in Hong Kong.

Abstract P2-12-22: Atypical ductal hyperplasia and breast cancers - A ten year clinical and pathological review on core biopsy, lumpectomy and mastectomy specimens

Introduction

Atypical ductal hyperplasia (ADH) is known to be associated with underlying pre-malignant or malignant breast conditions. Here we report our 10-year data on ADH found in core biopsy, lumpectomy and mastectomy specimens

Methods

From 1st January 2005 to 31st December 2014, a total of 104 core needle biopsy specimens and 218 lumpectomy / mastectomy specimens were found to contain ADH. Clinical, radiological and pathology data were retrieved and analysed from a prospectively-maintained database.

Results

Out of the 104 patients with core biopsy showing ADH, 101 patients received excision and 3 refused operation. 34 patients turned out to have ductal carcinoma in-situ (DCIS) on excision, while 6 had invasive ductal carcinoma (IDC), 1 had lobular carcinoma in-situ (LCIS) and 1 had angiosarcoma resulting in an upstaging rate of 40.4% (42/104). The remaining patients had benign lesions including papillary lesions, fibrocystic disease, or ADH alone. Multivariate analysis found that the only correlating factor for the presence of DCIS or IDC was suspicious mammographic features (BIRADS 4 or above) (P = 0.008 and 0.02 respectively) but not other parameters such as extent of micro-calcifications (P = 0.12) or age (P = 0.11).

Histopathological diagnosis after excision of lesions containing ADH on core biopsyExcisional Biopsy ResultNumber (%)DCIS34 (32.7%)ADH32 (30.8%)Benign27 (26%)IDC6 (5.8%)LCIS1 (0.9%)Angiosarcoma1 (0.9%)Refuse operation3 (2.9%)

218 lumpectomy or mastectomy specimens were found to harbor ADH. 62 (28.4%) had co-existing pre-malignant or malignant breast diseases. The only determining factor for the presence of malignant or pre-malignant condition was suspicious breast imaging features (BIRADS 4 or above) after multivariate analysis (P = 0.0003).

Co-existing conditions in the lumpectomy / mastectomy specimens with ADHCo-existing Patholog(ies)Number (%)Atypical Ductal Hyperplasia alone97 (44.4%)Fibroadenoma / Fibrocystic disease31 (14.2%)Intraductal papilloma22 (10%)Phyllodes tumor6 (2.8%)Ductal carcinoma in-situ36 (16.5%)Invasive ductal carcinoma23 (10.6%)Lobular carcinoma in-situ1 (0.5%)Invasive lobular carcinoma1 (0.5%)Malignant phyllodes tumor1 (0.5%)

Conclusion

ADH is closely related to the presence of invasive cancer or DCIS especially when suspicious breast imaging features are present. The upstaging rate is still high in patients where initial biopsy was ADH.

Citation Format: Co M, Kwong A. Atypical ductal hyperplasia and breast cancers - A ten year clinical and pathological review on core biopsy, lumpectomy and mastectomy specimens. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P2-12-22.

Interaction of a dengue virus NS1-derived peptide with the inhibitory receptor KIR3DL1 on natural killer cells

Killer immunoglobulin-like receptors (KIRs) interact with human leucocyte antigen (HLA) class I ligands and play a key role in the regulation and activation of NK cells. The functional importance of KIR-HLA interactions has been demonstrated for a number of chronic viral infections, but to date only a few studies have been performed in the context of acute self-limited viral infections. During our investigation of CD8(+) T cell responses to a conserved HLA-B57-restricted epitope derived from dengue virus (DENV) non-structural protein-1 (NS1), we observed substantial binding of the tetrameric complex to non-T/non-B lymphocytes in peripheral blood mononuclear cells (PBMC) from a long-standing clinical cohort in Thailand. We confirmed binding of the NS1 tetramer to CD56(dim) NK cells, which are known to express KIRs. Using depletion studies and KIR-transfected cell lines, we demonstrated further that the NS1 tetramer bound the inhibitory receptor KIR3DL1. Phenotypical analysis of PBMC from HLA-B57(+) subjects with acute DENV infection revealed marked activation of NS1 tetramer-binding natural killer (NK) cells around the time of defervescence in subjects with severe dengue disease. Collectively, our findings indicate that subsets of NK cells are activated relatively late in the course of acute DENV illness and reveal a possible role for specific KIR-HLA interactions in the modulation of disease outcomes.

Cross-sectional survey on the knowledge, attitude and practice of male Filipino seafarers on sexual health

The Philippines is currently the world's leading supplier of seafarers aboard foreign vessels, accounting for nearly a quarter of the world's maritime industry. Seafarers, being mobile, have a significant contribution impact on the worldwide spread of infectious diseases such as sexually transmitted infections (STIs). This study aims to determine the level of knowledge, as well as the attitudes and practices (KAP) of male Filipino seafarers regarding sexual health. A cross-sectional survey was administered through convenience sampling of male Filipino seafarers. The respondents showed the least knowledge about prevention, followed by transmission of STIs. The respondents showed adequate knowledge about risk factors such as multiple sex partners, and about transmission such as vertical spread. In addition, the respondents indicated their attitude and level of responsibility in informing their sexual partners in case they contract STIs and avoidance of high-risk partners. They also showed attitudes that predispose them to high-risk behaviour such as decreased sexual sensation caused by use of condoms and added pleasure in having intercourse with strangers. The majority of respondents were sexually active. Most have STI/HIV screening as part of their pre-employment medical exam. Positive practices include use of condoms, voluntary medical evaluation for STI's, and avoidance of high-risk partners. Negative practices include going to bars closely linked with prostitution, and most of the respondents had had sexual intercourse with sex workers overseas. Male seafarers appear to have double standards regarding women as sexual partners - about half had intercourse outside their stable relationships. They perceive protection as their sole discretion.

Family with three apparently balanced t(3;15) (p27;q22) translocation carriers. Association with deficits in language acquisition and mental retardation: a possible example of position effect in man

A father, son, and daughter had a (3;15) (p27;q22) simple reciprocal translocation. No abnormality in the G-banding pattern was noted. The girl was most severely affected; she had an abnormal phenotype, noticeable delay in receptive and expressive language development, bilateral hearing impairment, and definite mental retardation. The boy had a moderate delay in receptive language skills, had moderate hearing impairment in one ear, and showed mild mental retardation. The father has low-set ears, some deficits in receptive language skills, is illiterate, and was found to be borderline mentally retarded. The mother and younger child do not have the translocation and are normal in terms of phenotype, intellect, and verbal skills. The accumulating evidence suggests that balanced translocations are associated with an increased frequency of intellectual deficit and congenital anomalies, and the cytogenetic mechanism may be that of position effect.