Low-grade Endometrial Stromal Sarcoma With Sex Cord-like Differentiation and PHF1-JAZF1 Fusion With Deletions: A Diagnostic Pitfall of JAZF1 FISH.

The molecular knowledge of endometrial stromal neoplasms has been rapidly increasing and is considered complementary to morphologic and immunohistochemical findings for better categorization of these tumors. The most common molecular alteration observed in low-grade endometrial stromal sarcomas is the JAZF1-SUZ12 fusion, whereas, low-grade endometrial stromal sarcoma with sex cord-like differentiation have been shown more commonly to have fusions involving PHF1. Herein, we present a low-grade endometrial stromal sarcoma with sex cord-like differentiation with a fluorescence in situ hybridization showing the apparent loss of one copy of JAZF1 5' and 3' signals, rather than the expected "break-apart" pattern seen in the setting of a JAZF1 fusion. The case was then further evaluated by chromosome microarray and RNA fusion analysis. Overall, the molecular findings supported a PHF1-JAZF1 fusion with deletions right before and after the JAZF1 locus, impairing probe binding and resulting in the unusual "deletion" pattern observed in the JAZF1 fluorescence in situ hybridization, which would not intuitively suggest a fusion involving JAZF1. This case illustrates the importance of integration of morphological and molecular findings as well as the limitations of fluorescence in situ hybridization in detecting fusions, particularly in the setting of more complex chromosomal alterations even though the fusion partners are well-known.

Pathological chemotherapy response score is prognostic in tubo-ovarian high-grade serous carcinoma: A systematic review and meta-analysis of individual patient data.

OBJECTIVE: There is a need to develop and validate biomarkers for treatment response and survival in tubo-ovarian high-grade serous carcinoma (HGSC). The chemotherapy response score (CRS) stratifies patients into complete/near-complete (CRS3), partial (CRS2), and no/minimal (CRS1) response after neoadjuvant chemotherapy (NACT). Our aim was to review current evidence to determine whether the CRS is prognostic in women with tubo-ovarian HGSC treated with NACT. METHODS: We established an international collaboration to conduct a systematic review and meta-analysis, pooling individual patient data from 16 sites in 11 countries. Patients had stage IIIC/IV HGSC, 3-4 NACT cycles and >6-months follow-up. Random effects models were used to derive combined odds ratios in the pooled population to investigate associations between CRS and progression free and overall survival (PFS and OS). RESULTS: 877 patients were included from published and unpublished studies. Median PFS and OS were 15 months (IQR 5-65) and 28 months (IQR 7-92) respectively. CRS3 was seen in 249 patients (28%). The pooled hazard ratios (HR) for PFS and OS for CRS3 versus CRS1/CRS2 were 0·55 (95% CI, 0·45-0·66; P < 0·001) and 0·65 (95% CI 0·50-0·85, P = 0·002) respectively; no heterogeneity was identified (PFS: Q = 6·42, P = 0·698, I2 = 0·0%; OS: Q = 6·89, P = 0·648, I2 = 0·0%). CRS was significantly associated with PFS and OS in multivariate models adjusting for age and stage. Of 306 patients with known germline BRCA1/2 status, those with BRCA1/2 mutations (n = 80) were more likely to achieve CRS3 (P = 0·027). CONCLUSIONS: CRS3 was significantly associated with improved PFS and OS compared to CRS1/2. This validation of CRS in a real-world setting demonstrates it to be a robust and reproducible biomarker with potential to be incorporated into therapeutic decision-making and clinical trial design.

MicroRNAs miR-7 and miR-340 predict response to neoadjuvant chemotherapy in breast cancer.

PURPOSE: miRNAs have been linked to chemosensitivity of breast cancer cells in vitro. In patients, however, there is no clinically validated method for predicting chemotherapy response. The aim of this study was to assess whether (I) a specific pattern of miRNA expression in pretherapeutic biopsies can predict response to neoadjuvant chemotherapy, and (II) differential miRNA expression in residual tumor after completion of chemotherapy allows further prognostic stratification of non-responding patients. METHODS: Sixty-four patients with newly diagnosed large (≥3 cm) or locally advanced primary breast cancers who underwent neoadjuvant anthracycline/taxane-based chemotherapy were included. Relative expression of 10 miRNAs likely to be associated with chemotherapy response (miR-7,-21,-29a,-29b,-34a,-125b,-155,-200c,-340,-451) was determined by quantitative RT-PCR from pretherapeutic biopsies (n = 64) and residual invasive tumor after chemotherapy (n = 42). Pathologic complete response (pCR) defined by absence of invasive tumor served as reference standard. In addition, miRNA expression was compared with disease-free and overall survival. RESULTS: Nine (14%) of 64 patients achieved pCR. High expression of miR-7 and low expression of miR-340 in pretherapeutic biopsies predicted pCR with a negative predictive value of 96 and 97%, respectively (specificity 54 and 57%). The combined profile of miR-7high/miR-340low demonstrated improved specificity of 86% while maintaining a high negative predictive value (96%) to identify non-responders. Pretherapeutic expression of miR-200c and miR-155 showed prognostic information, and low expression was associated with increased overall survival (115 vs. 90 months, p ≤ 0.03). After chemotherapy, the overall survival of patients with residual invasive tumor was better for those demonstrating low miR-7 or high miR-125b (p = 0.01). CONCLUSIONS: Intratumoral expression of miR-7 and miR-340 prior to neoadjuvant chemotherapy could be used to predict pCR and a profile of miR-7low or miR-340high identified patients unlikely to achieve pCR who might benefit from alternative treatment options including earlier surgery. Our study identifies miRNAs as promising predictive biomarkers, which could aid in optimization of breast cancer management and treatment stratification.

CXCL9 and CXCL10 predict survival and are regulated by cyclooxygenase inhibition in advanced serous ovarian cancer.

BACKGROUND: Tumour-infiltrating lymphocytes (TILs) are associated with improved survival in several epithelial cancers. The two chemokines CXCL9 and CXCL10 facilitate chemotactic recruitment of TILs, and their intratumoral accumulation is a conceivable way to improve TIL-dependent immune intervention in cancer. However, the prognostic impact of CXCL9 and CXCL10 in high-grade serous ovarian cancer (HGSC) is largely unknown. METHODS: One hundred and eighty four cases of HGSC were immunohistochemically analyzed for CXCL9, CXCL10. TILs were assessed using CD3, CD56 and FOXP3 staining. Chemokine regulation was investigated using the ovarian cancer cell lines OV-MZ-6 and SKOV-3. RESULTS: High expression of CXCL9 and CXCL10 was associated with an approximately doubled overall survival (n=70, CXCL9: HR 0.41; P=0.006; CXCL10: HR 0.46; P=0.010) which was confirmed in an independent validation set (n=114; CXCL9: HR 0.60; P=0.019; CXCL10: HR 0.52; P=0.005). Expression of CXCR3 ligands significantly correlated with TILs. In human ovarian cancer cell lines the cyclooxygenase (COX) metabolite Prostaglandin E2 was identified as negative regulator of chemokine secretion, whereas COX inhibition by indomethacin significantly upregulated CXCL9 and CXCL10. In contrast, celecoxib, the only COX inhibitor prospectively evaluated for therapy of ovarian cancer, suppressed NF-κB activation and inhibited chemokine release. CONCLUSION: Our results support the notion that CXCL9 and CXCL10 exert tumour-suppressive function by TIL recruitment in human ovarian cancer. COX inhibition by indomethacin, not by celecoxib, may be a promising approach to concomitantly improve immunotherapies.

Clinical relevance of kallikrein-related peptidase 6 (KLK6) and 8 (KLK8) mRNA expression in advanced serous ovarian cancer.

Most members of the kallikrein-related peptidase family have been demonstrated to be dysregulated in ovarian cancer and modulate tumor growth, migration, invasion, and resistance to chemotherapy. In the present study, we assessed the mRNA expression levels of KLK6 and KLK8 by quantitative PCR in 100 patients with advanced serous ovarian cancer FIGO stage III/IV. A pronounced correlation between KLK6 and KLK8 mRNA expression (rs = 0.636, p < 0.001) was observed, indicating coordinate expression of both peptidases. No significant associations of clinical parameters with KLK6, KLK8, and a combined score KLK6+KLK8 were found. In univariate Cox regression analysis, elevated mRNA levels of KLK6 were significantly linked with shortened overall survival (OS) (hazard ratio [HR] = 2.07, p = 0.007). While KLK8 values were not associated with patients' outcome, high KLK6+KLK8 values were significantly associated with shorter progression-free survival (HR = 1.82, p = 0.047) and showed a trend towards significance in the case of OS (HR = 1.82, p = 0.053). Strikingly, in multivariable analysis, elevated KLK6 mRNA values, apart from residual tumor mass, remained an independent predictive marker for poor OS (HR = 2.33, p = 0.005). As KLK6 mRNA and protein levels correlate, KLK6 may represent an attractive therapeutic target for potent and specific inhibitors of its enzymatic activity.

Identification of BRCA1-like triple-negative breast cancers by quantitative multiplex-ligation-dependent probe amplification (MLPA) analysis of BRCA1-associated chromosomal regions: a validation study.

BACKGROUND: Triple-negative breast cancer (TNBC) with a BRCA1-like molecular signature has been demonstrated to remarkably respond to platinum-based chemotherapy and might be suited for a future treatment with poly(ADP-ribose)polymerase (PARP) inhibitors. In order to rapidly assess this signature we have previously developed a multiplex-ligation-dependent probe amplification (MLPA)-based assay. Here we present an independent validation of this assay to confirm its important clinical impact. METHODS: One-hundred-forty-four TNBC tumor specimens were analysed by the MLPA-based "BRCA1-like" test. Classification into BRCA1-like vs. non-BRCA1-like samples was performed by our formerly established nearest shrunken centroids classifier. Data were subsequently compared with the BRCA1-mutation/methylation status of the samples. T-lymphocyte infiltration and expression of the main target of PARP inhibitors, PARP1, were assessed on a subset of samples by immunohistochemistry. Data acquisition and interpretation was performed in a blinded manner. RESULTS: In the studied TNBC cohort, 63 out of 144 (44 %) tumors were classified into the BRCA1-like category. Among these, the MLPA test correctly predicted 15 out of 18 (83 %) samples with a pathogenic BRCA1-mutation and 20 of 22 (91 %) samples exhibiting BRCA1-promoter methylation. Five false-negative samples were observed. We identified high lymphocyte infiltration as one possible basis for misclassification. However, two falsely classified BRCA1-mutated tumors were also characterized by rather non-BRCA1-associated histopathological features such as borderline ER expression. The BRCA1-like vs. non-BRCA1-like signature was specifically enriched in high-grade (G3) cancers (90 % vs. 58 %, p = 0.0004) and was also frequent in tumors with strong (3+) nuclear PARP1 expression (37 % vs. 16 %; p = 0.087). CONCLUSIONS: This validation study confirmed the good performance of the initial MLPA assay which might thus serve as a valuable tool to select patients for platinum-based chemotherapy regimens. Moreover, frequent PARP1 upregulation in BRCA1-like tumors may also point to susceptibility to treatment with PARP inhibitors. Limitations are the requirement of high tumor content and high-quality DNA.

Hypomethylation of the MMP7 promoter and increased expression of MMP7 distinguishes the basal-like breast cancer subtype from other triple-negative tumors.

Identification of novel targets for the treatment of basal-like breast cancer is essential for improved outcomes in patients with this disease. This study investigates the association of MMP7 expression and MMP7 promoter methylation with subtype and outcome in breast cancer patient cohorts. Immunohistochemical analysis was performed on a breast cancer tissue microarray and validated in independent histological samples. MMP7 expression significantly correlated with patient age, tumor size, triple-negative (TN) status, and recurrence. Analysis of publically available datasets confirmed MMP7 gene expression as a prognostic marker of breast cancer metastasis, particularly metastasis to the brain and lungs. Methylation of the MMP7 promoter was assessed by methylation-specific PCR in a panel of breast cancer cell lines and patient tumor samples. Hypomethylation of the MMP7 promoter significantly correlated with TN status in DNA from patient tumor samples, and this association was confirmed using The Cancer Genome Atlas (TCGA) dataset. Evaluation of a panel of breast cancer cell lines and data from the Curtis and TCGA breast carcinoma datasets revealed that elevated MMP7 expression and MMP7 promoter hypomethylation are specific biomarkers of the basal-like molecular subtype which shares considerable, but not complete, overlap with the clinical TN subtype. Importantly, MMP7 expression was identified as an independent predictor of pathological complete response in a large breast cancer patient cohort. Combined, these data suggest that MMP7 expression and MMP7 promoter methylation may be useful as prognostic biomarkers. Furthermore, MMP7 expression and promoter methylation analysis may be effective mechanisms to distinguish basal-like breast cancers from other triple-negative subtypes. Finally, these data implicate MMP7 as a potential therapeutic target for the treatment of basal-like breast cancers.

Computational pathology identifies immune-mediated collagen disruption to predict clinical outcomes in gynecologic malignancies.

BACKGROUND: The role of immune cells in collagen degradation within the tumor microenvironment (TME) is unclear. Immune cells, particularly tumor-infiltrating lymphocytes (TILs), are known to alter the extracellular matrix, affecting cancer progression and patient survival. However, the quantitative evaluation of the immune modulatory impact on collagen architecture within the TME remains limited. METHODS: We introduce CollaTIL, a computational pathology method that quantitatively characterizes the immune-collagen relationship within the TME of gynecologic cancers, including high-grade serous ovarian (HGSOC), cervical squamous cell carcinoma (CSCC), and endometrial carcinomas. CollaTIL aims to investigate immune modulatory impact on collagen architecture within the TME, aiming to uncover the interplay between the immune system and tumor progression. RESULTS: We observe that an increased immune infiltrate is associated with chaotic collagen architecture and higher entropy, while immune sparse TME exhibits ordered collagen and lower entropy. Importantly, CollaTIL-associated features that stratify disease risk are linked with gene signatures corresponding to TCA-Cycle in CSCC, and amino acid metabolism, and macrophages in HGSOC. CONCLUSIONS: CollaTIL uncovers a relationship between immune infiltration and collagen structure in the TME of gynecologic cancers. Integrating CollaTIL with genomic analysis offers promising opportunities for future therapeutic strategies and enhanced prognostic assessments in gynecologic oncology.

The role of cells that are part of our immune system in altering the structure of the protein collagen within cancers is not fully understood, particularly within cancers that affect women such as ovarian, cervical and uterine cancers. Here, we developed a computer-based method called CollaTIL to explore how immune cells influence collagen in these tumors and affect their growth. We found that a higher presence of immune cells leads to less organized collagen in the tumor. Conversely, when there are fewer immune cells, the collagen tends to be more structured. Additionally, CollaTIL identifies patterns that predict patient outcomes in these cancers. These findings not only enhance our understanding of tumor biology but also may be useful in helping clinicians to predict which patients are at risk of their disease progressing.

LRIG1 engages ligand VISTA and impairs tumor-specific CD8+ T cell responses.

Immune checkpoint blockade is a promising approach to activate antitumor immunity and improve the survival of patients with cancer. V-domain immunoglobulin suppressor of T cell activation (VISTA) is an immune checkpoint target; however, the downstream signaling mechanisms are elusive. Here, we identify leucine-rich repeats and immunoglobulin-like domains 1 (LRIG1) as a VISTA binding partner, which acts as an inhibitory receptor by engaging VISTA and suppressing T cell receptor signaling pathways. Mice with T cell-specific LRIG1 deletion developed superior antitumor responses because of expansion of tumor-specific cytotoxic T lymphocytes (CTLs) with increased effector function and survival. Sustained tumor control was associated with a reduction of quiescent CTLs (TCF1+ CD62Lhi PD-1low) and a reciprocal increase in progenitor and memory-like CTLs (TCF1+ PD-1+). In patients with melanoma, elevated LRIG1 expression on tumor-infiltrating CD8+ CTLs correlated with resistance to immunotherapies. These results delineate the role of LRIG1 as an inhibitory immune checkpoint receptor and propose a rationale for targeting the VISTA/LRIG1 axis for cancer immunotherapy.

VISTA promotes the metabolism and differentiation of myeloid-derived suppressor cells by STAT3 and polyamine-dependent mechanisms.

Myeloid-derived suppressor cells (MDSCs) impair antitumor immune responses. Identifying regulatory circuits during MDSC development may bring new opportunities for therapeutic interventions. We report that the V-domain suppressor of T cell activation (VISTA) functions as a key enabler of MDSC differentiation. VISTA deficiency reduced STAT3 activation and STAT3-dependent production of polyamines, which causally impaired mitochondrial respiration and MDSC expansion. In both mixed bone marrow (BM) chimera mice and myeloid-specific VISTA conditional knockout mice, VISTA deficiency significantly reduced tumor-associated MDSCs but expanded monocyte-derived dendritic cells (DCs) and enhanced T cell-mediated tumor control. Correlated expression of VISTA and arginase-1 (ARG1), a key enzyme supporting polyamine biosynthesis, was observed in multiple human cancer types. In human endometrial cancer, co-expression of VISTA and ARG1 on tumor-associated myeloid cells is associated with poor survival. Taken together, these findings unveil the VISTA/polyamine axis as a central regulator of MDSC differentiation and warrant therapeutically targeting this axis for cancer immunotherapy.

Monitoring mouse papillomavirus-associated cancer development using longitudinal Pap smear screening.

A substantial percentage of the population remains at risk for cervical cancer due to pre-existing human papillomavirus (HPV) infections, despite prophylactic vaccines. Early diagnosis and treatment are crucial for better disease outcomes. The development of new treatments heavily relies on suitable preclinical model systems. Recently, we established a mouse papillomavirus (MmuPV1) model that is relevant to HPV genital pathogenesis. In the current study, we validated the use of Papanicolaou (Pap) smears, a valuable early diagnostic tool for detecting HPV cervical cancer, to monitor disease progression in the MmuPV1 mouse model. Biweekly cervicovaginal swabs were collected from the MmuPV1-infected mice for viral DNA quantitation and cytology assessment. The Pap smear slides were evaluated for signs of epithelial cell abnormalities using the 2014 Bethesda system criteria. Tissues from the infected mice were harvested at various times post-viral infection for additional histological and virological assays. Over time, increased viral replication was consistent with higher levels of viral DNA, and it coincided with an uptick in epithelial cell abnormalities with higher severity scores noted as early as 10 weeks after viral infection. The cytological results also correlated with the histological evaluation of tissues harvested simultaneously. Both immunocompromised and immunocompetent mice with squamous cell carcinoma (SCC) cytology also developed vaginal SCCs. Notably, samples from the MmuPV1-infected mice exhibited similar cellular abnormalities compared to the corresponding human samples at similar disease stages. Hence, Pap smear screening proves to be an effective tool for the longitudinal monitoring of disease progression in the MmuPV1 mouse model. IMPORTANCE: Papanicolaou (Pap) smear has saved millions of women's lives as a valuable early screening tool for detecting human papillomavirus (HPV) cervical precancers and cancer. However, more than 200,000 women in the United States alone remain at risk for cervical cancer due to pre-existing HPV infection-induced precancers, as there are currently no effective treatments for HPV-associated precancers and cancers other than invasive procedures including a loop electrosurgical excision procedure (LEEP) to remove abnormal tissues. In the current study, we validated the use of Pap smears to monitor disease progression in our recently established mouse papillomavirus model. To the best of our knowledge, this is the first study that provides compelling evidence of applying Pap smears from cervicovaginal swabs to monitor disease progression in mice. This HPV-relevant cytology assay will enable us to develop and test novel antiviral and anti-tumor therapies using this model to eliminate HPV-associated diseases and cancers.

Computational Image and Molecular Analysis Reveal Unique Prognostic Features of Immune Architecture in African Versus European American Women with Endometrial Cancer.

Endometrial cancer (EC) disproportionately affects African American (AA) women in terms of progression and death. In our study, we sought to employ computerized image and bioinformatic analysis to tease out morphologic and molecular differences in EC between AA and European-American (EA) populations. We identified the differences in immune cell spatial patterns between AA and EA populations with markers of tumor biology, including histologic and molecular subtypes. The models performed best when they were trained and validated using data from the same population. Unsupervised clustering revealed a distinct association between immune cell features and known molecular subtypes of endometrial cancer that varied between AA and EA populations. Our genomic analysis revealed two distinct and novel gene sets with mutations associated with improved prognosis in AA and EA patients. Our study findings suggest the need for population-specific risk prediction models for women with endometrial cancer.

Modulation of CXCR3 ligand secretion by prostaglandin E2 and cyclooxygenase inhibitors in human breast cancer.

INTRODUCTION: In murine breast cancer models, the two interferon-gamma (IFN-γ) inducible chemokines and CXC-chemokine receptor 3 (CXCR3) receptor ligands, monokine induced by γ-interferon (CXCL9) and interferon-γ-inducible protein-10 (CXCL10) impair tumor growth and metastasis formation through recruitment of natural killer (NK) cells and tumor-suppressive T lymphocytes. In human breast cancer, CXCL9 mRNA overexpression correlates with the number of tumor infiltrating lymphocytes and predicts response to different chemotherapeutic regimens. Raising the intratumoral CXCR3 ligand concentration is therefore a possible way to enhance immune intervention in breast cancer. Little is known, however, about expression levels and regulation of these chemokines in human breast cancer. Since the inhibition of cyclooxygenases (COX) has been shown to reduce tumor growth and incidence of metastases in a lymphocytic and IFN-γ dependent manner, we argued that COX isoenzymes are a pharmacologic target to increase intratumoral CXCR3 ligand concentration in human breast cancer. METHODS: CXCL9 was visualized in breast cancer specimens by immunohistochemistry, expression levels of CXCL9 and cyclooxygenases were determined by ELISA and western blotting, respectively. For regulation studies, Michigan Cancer Foundation-7 (MCF-7) and M.D. Anderson - Metastatic Breast 231 (MDA-MB 231) breast cancer cells were stimulated with IFN-γ with or without prostaglandin E2 (PGE2) or COX inhibitors (indomethacin, acetylsalicylic acid (ASA), celecoxib). CXCR3 ligand release from cells was measured by ELISA. RESULTS: Within the tumor microenvironment, cancer cells are the major source of CXCL9. PGE2 impairs IFN-γ mediated CXCL9 and CXCL10 release from MCF-7 and MDA-MB 231 cells, and inhibition of endogenous cyclooxygenases by indomethacin or ASA correspondingly increases this secretion. Otherwise, high concentrations of the Cyclooxygenase-2 (COX-2) specific antagonist celecoxib have opposite effects and impair CXCL9 and CXCL10 release. In human breast cancer tissue specimens there is an inverse correlation between COX-2 overexpression and CXCL9 concentration, suggesting that the observed in vitro effects are of importance in vivo as well. CONCLUSIONS: Suppressing endogenous PGE2 synthesis by cyclooxygenase inhibition increases CXCL9 and CXCL10 release from breast cancer cells and is therefore a pharmacologic candidate to enhance intratumoral immune infiltration. Yet, to this end the unselective COX inhibitors ASA and indomethacin seem preferable to celecoxib that at higher concentrations reduces CXCR3 ligand release most probably due to COX independent mechanisms.

Phenotypic and functional characterisation of the luminal cell hierarchy of the mammary gland.

INTRODUCTION: The organisation of the mammary epithelial hierarchy is poorly understood. Our hypothesis is that the luminal cell compartment is more complex than initially described, and that an understanding of the developmental relationships within this lineage will help in understanding the cellular context in which breast tumours occur. METHODS: We used fluorescence-activated cell sorting along with in vitro and in vivo functional assays to examine the growth and differentiation properties of distinct subsets of human and mouse mammary epithelial cells. We also examined how loss of steroid hormones influenced these populations in vivo. Gene expression profiles were also obtained for all the purified cell populations and correlated to those obtained from breast tumours. RESULTS: The luminal cell compartment of the mouse mammary gland can be resolved into nonclonogenic oestrogen receptor-positive (ER+) luminal cells, ER+ luminal progenitors and oestrogen receptor-negative (ER-) luminal progenitors. The ER+ luminal progenitors are unique in regard to cell survival, as they are relatively insensitive to loss of oestrogen and progesterone when compared with the other types of mammary epithelial cells. Analysis of normal human breast tissue reveals a similar hierarchical organisation composed of nonclonogenic luminal cells, and relatively differentiated (EpCAM+CD49f+ALDH-) and undifferentiated (EpCAM+CD49f+ALDH+) luminal progenitors. In addition, approximately one-quarter of human breast samples examined contained an additional population that had a distinct luminal progenitor phenotype, characterised by low expression of ERBB3 and low proliferative potential. Parent-progeny relationship experiments demonstrated that all luminal progenitor populations in both species are highly plastic and, at low frequencies, can generate progeny representing all mammary cell types. The ER- luminal progenitors in the mouse and the ALDH+ luminal progenitors in the human appear to be analogous populations since they both have gene signatures that are associated with alveolar differentiation and resemble those obtained from basal-like breast tumours. CONCLUSION: The luminal cell compartment in the mammary epithelium is more heterogeneous than initially perceived since progenitors of varying levels of luminal cell differentiation and proliferative capacities can be identified. An understanding of these cells will be essential for understanding the origins and the cellular context of human breast tumours.

Histopathologic features of ovarian borderline tumors are not predictive of clinical outcome.

OBJECTIVES: Ovarian borderline tumors (BOTs) generally have an excellent prognosis, although recurrences and malignant transformation can occur. Our aim was to compare clinicopathologic features of BOT with clinical outcome. METHODS: In seventy consecutive BOTs clinicopathologic parameters, tumor cell proliferation (Ki67) and in selected cases KRAS, BRAF and p53 mutational status were analyzed with recurrence-free and overall survival as the endpoints. RESULTS: Sixty-one (87%) patients presented with FIGO stage I, 3 stage II, and 6 stage III. Thirty-four patients had serous and 36 mucinous BOT (30 intestinal and 6 endocervical subtypes). Non-invasive peritoneal implants occurred in 9 patients, and no invasive implants were observed. Recurrence-free and overall survival rates were 91% and 99%, respectively, at a mean follow-up of 63 months. Disease recurrence occurred in 6 cases (all FIGO stage I) including 3 serous, 1 mucinous-intestinal, and 2 mucinous-endocervical subtypes. Mean time to recurrence was 27 months (range 8-68). The recurrence rate following fertility-conserving surgery was 31% (5/16) compared to 2% (1/54) after bilateral salpingo-oophorectomy. Neither peritoneal implants (9/70), micropapillary pattern (2/34), microinvasion (4/70), nor increased tumor cell proliferation was associated with a higher recurrence rate. The frequency of KRAS or BRAF mutations was 50% (3/6 recurrences and 3/6 controls; 4 KRAS, 2 BRAF mutations). No p53 mutations (0/12) were detected in primary or recurrent BOTs. CONCLUSIONS: Histopathologic parameters were not predictive of BOT recurrence including previously suggested risk factors such as micropapillary pattern and microinvasion. However, fertility-conserving surgery and incomplete surgical staging were associated with a higher risk for recurrence.

The Geographic Context of Racial Disparities in Aggressive Endometrial Cancer Subtypes: Integrating Social and Environmental Aspects to Discern Biological Outcomes.

The number of Endometrial Carcinoma (EC) diagnoses is projected to increase substantially in coming decades. Although most ECs have a favorable prognosis, the aggressive, non-endometrioid subtypes are disproportionately concentrated in Black women and spread rapidly, making treatment difficult and resulting in poor outcomes. Therefore, this study offers an exploratory spatial epidemiological investigation of EC patients within a U.S.-based health system's institutional cancer registry (n = 1748) to search for and study geographic patterns. Clinical, demographic, and geographic characteristics were compared by histotype using chi-square tests for categorical and t-tests for continuous variables. Multivariable logistic regression evaluated the impact of risks on these histotypes. Cox proportional hazard models measured risks in overall and cancer-specific death. Cluster detection indicated that patients with the EC non-endometrioid histotypes exhibit geographic clustering in their home address, such that congregate buildings can be identified for targeted outreach. Furthermore, living in a high social vulnerability area was independently associated with non-endometrioid histotypes, as continuous and categorical variables. This study provides a methodological framework for early, geographically targeted intervention; social vulnerability associations require further investigation. We have begun to fill the knowledge gap of geography in gynecologic cancers, and geographic clustering of aggressive tumors may enable targeted intervention to improve prognoses.

Non-phosphorylatable cyclin D1 mutant potentiates endometrial hyperplasia and drives carcinoma with Pten loss.

Cyclin D1 is a regulatory subunit of -Cyclin Dependent Kinases 4 and 6 (CDK4/6) and regulates progression from G1 to S phase of the cell cycle. Dysregulated cyclin D1-CDK4/6 contributes to abnormal cell proliferation and tumor development. Phosphorylation of threonine 286 of cyclin D1 is necessary for ubiquitin-dependent degradation. Non-phosphorylatable cyclin D1 mutants are stabilized and concentrated in the nucleus, contributing to genomic instability and tumor development. Studies investigating the tumor-promoting functions of cyclin D1 mutants have focused on the use of artificial promoters to drive the expression which unfortunately may not accurately reflect tumorigenic functions of mutant cyclin D1 in cancer development. We have generated a conditional knock-in mouse model where cyclin D1T286A is expressed under the control of its endogenous promoter following Cre-dependent excision of a lox-stop-lox sequence. Acute expression of cyclin D1T286A following tamoxifen-inducible Cre recombinase triggers inflammation, lymphocyte abnormality and ultimately mesenteric tumors in the intestine. Tissue-specific expression of cyclin D1T286A in the uterus and endometrium cooperates with Pten loss to drive endometrial hyperplasia and cancer. Mechanistically, cyclin D1T286A mutant activates NF-κB signaling, augments inflammation, and contributes to tumor development. These results indicate that mutation of cyclin D1 at threonine 286 has a critical role in regulating inflammation and tumor development.

PET/CT Variants and Pitfalls in Breast Cancers.

There are a number of normal variants and pitfalls which are important to consider when evaluating F-18 Fluorodeoxyglucose (FDG) with Positron Emission Tomography (PET) in breast cancer patients. Although FDG-PET is not indicated for the initial diagnosis of breast cancer, focally increased glucose metabolism within breast tissue represents a high likelihood for a neoplastic process and requires further evaluation. Focally increased glucose metabolism is not unique to breast cancer. Other malignancies such as lymphoma, metastases from solid tumors as well as inflammatory changes also may demonstrate increased glucose metabolism either within the breast or at other sites throughout the body. Importantly, benign breast disease may also exhibit increased glucose metabolism, limiting the specificity of FDG-PET. Breast cancer has a wide range of metabolic activity attributed to tumor heterogeneity and breast cancer subtype. Intracellular signaling pathways regulating tumor glucose utilization contribute to these pitfalls of PET/CT in breast cancer. The evaluation of axillary lymph nodes by FDG-PET is less accurate than sentinel lymph node procedure, however is very accurate in identifying level II and III axillary lymph node metastases or retropectoral metastases. It is important to note that non-malignant inflammation in lymph nodes are often detected by modern PET/CT technology. Therefore, particular consideration should be given to recent vaccinations, particularly to COVID-19, which can commonly result in increased metabolic activity of axillary nodes. Whole body FDG-PET for staging of breast cancer requires specific attention to physiologic variants of FDG distribution and a careful comparison with co-registered anatomical imaging. The most important pitfalls are related to inflammatory changes including sarcoidosis, sarcoid like reactions, and other granulomatous diseases as well as secondary neoplastic processes.