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Approximately 40% of vulvar squamous cell carcinoma (vSCC) cases are etiologically associated with high-risk human papillomaviruses (HPVs) of the alpha genera (α-HPV) that cause other anogenital cancers; however, the etiology of α-HPV-negative vSCC is poorly understood. HPVs of the beta genera (β-HPV) are risk factors for cutaneous squamous cell carcinoma (cSCC) and may be related to carcinomas originating in other cutaneous sites such as the vulva. In this study, we investigate the presence of β-HPVs, with an emphasis on p16-negative squamous lesions adjacent to vSCC. We subjected 28 vulvar squamous intraepithelial lesions adjacent to vSCC for comprehensive HPV genotyping, p16 and p53 immunohistochemistry, and consensus morphology review. Selected cases were subjected to qPCR and RNA in situ hybridization. Clinical data were obtained from medical records. β-HPV DNA was detected in eight of ten p16-negative lesions and three of fourteen p16-positive high-grade squamous intraepithelial lesions. The HPV DNA loads in vulvar squamous intraepithelial lesions ranged between less than 1 HPV DNA copy per cell to more than 100 HPV DNA copies per cell. This is, to the best of our knowledge, the first report of the association of p16-negative vulvar intraepithelial squamous lesions with detection of β-HPVs. These findings expand possible etiologic mechanisms that may contribute to p16-negative lesions of the vulva. [ABSTRACT FROM AUTHOR]

Female SV40 C3(1) T-antigen (C3(1)/TAg) transgenic mice develop mammary tumors that are molecularly similar to human basal-like breast cancers with 100% incidence at 16 weeks of age. To determine the requirement for growth hormone (GH) signaling in these tumors, genetic crosses were used to create cohorts of female mice that were homozygous for a floxed growth hormone receptor (Ghr) gene and carried one copy each of the Rosa-Cre-ERT2 transgene and the C3(1)/TAg transgene (Ghr flox/flox; Rosa-Cre-ERT2; C3(1)/TAg+/0 mice). When the largest mammary tumor reached 200 mm3, mice were treated with tamoxifen to delete Ghr or with vehicle as a control. An additional group of Ghr flox/flox; C3(1)/TAg+/0 mice were also treated with tamoxifen when the largest mammary tumor reached 200 mm3 as a control for the effects of tamoxifen. After 3 weeks, tumors in mice in which Ghr was deleted began to shrink while vehicle and tamoxifen treatment control mouse tumors continued to grow. Pathological analysis of tumors revealed similar growth patterns and varying levels of necrosis throughout all groups. A decrease in cancer cell proliferation in Ghr-/- tumors relative to controls was observed as measured by Ki67 immunohistochemistry labeling index. These data suggest that even established C3(1)/TAg mammary tumors are dependent on the GH/IGF-1 axis. [ABSTRACT FROM AUTHOR]

Pancreatic and ampullary cancers remain highly morbid diseases for which accurate clinical predictions are needed for precise therapeutic predictions. Patient-derived cancer organoids have been widely adopted; however, prior work has focused on well-level therapeutic sensitivity. To characterize individual oligoclonal units of therapeutic response, we introduce a low-volume screening assay, including an automated alignment algorithm. The oligoclonal growth response was compared against validated markers of response, including well-level viability and markers of single-cell viability. Line-specific sensitivities were compared with clinical outcomes. Automated alignment algorithms were generated to match organoids across time using coordinates across a single projection of Z-stacked images. After screening for baseline size (50 μm) and circularity (>0.4), the match efficiency was found to be optimized by accepting the diffusion thresholded with the root mean standard deviation of 75 μm. Validated well-level viability showed a limited correlation with the mean organoid size (R = 0.408), and a normalized growth assayed by normalized changes in area (R = 0.474) and area (R = 0.486). Subclonal populations were defined by both residual growth and the failure to induce apoptosis and necrosis. For a culture with clinical resistance to gemcitabine and nab-paclitaxel, while a therapeutic challenge induced a robust effect in inhibiting cell growth (GΔ = 1.53), residual oligoclonal populations were able to limit the effect on the ability to induce apoptosis (GΔ = 0.52) and cell necrosis (GΔ = 1.07). Bioengineered approaches are feasible to capture oligoclonal heterogeneity in organotypic cultures, integrating ongoing efforts for utilizing organoids across cancer types as integral biomarkers and in novel therapeutic development. [ABSTRACT FROM AUTHOR]

The artemisinin family of compounds is cytopathic in certain cancer cell lines that are positive for human papillomaviruses (HPV) and can potentially drive the regression of dysplastic lesions. We evaluated the efficacy of topical dihydroartemisinin (DHA) on cervical dysplasia and anal dysplasia in two papillomavirus mouse models: K14E6/E7 transgenic mice, which express HPV16 oncogenes; and immunodeficient NOD/SCID gamma (NSG) mice infected with Mus musculus papillomavirus (MmuPV1). Mice started treatment with DHA at 25 weeks of age (K14E6/E7) or 20 weeks post infection (MmuPV1-infected), when the majority of mice are known to have papillomavirus-induced low- to high-grade dysplasia. Mice were treated with or without topical DHA at the cervix or anus and with or without topical treatment with the chemical carcinogen 7,12 dimethylbenz(a)anthracene (DMBA) at the anus of in transgenic mice to induce neoplastic progression. Mice were monitored for overt tumor growth, and tissue was harvested after 20 weeks of treatment and scored for severity of histological disease. For MmuPV1-infected mice, anogenital lavages were taken to monitor for viral clearance. Tissues were also evaluated for viral gene expression at the RNA and/or protein levels. Treatment with topical DHA did not reduce dysplasia in the anogenital tract in either papillomavirus-induced mouse model and did not prevent progression to anal cancer in the DMBA-treated K14E6/E7 mice. [ABSTRACT FROM AUTHOR]

Recent evidence supports the fimbriae of the fallopian tube as one origin site for high-grade serous ovarian cancer (HGSOC). The progression of many solid tumors is accompanied by changes in the microenvironment, including alterations of the extracellular matrix (ECM). Therefore, we sought to determine the ECM composition of the benign fallopian tube and changes associated with serous tubal intraepithelial carcinomas (STICs), precursors of HGSOC. The ECM composition of benign human fallopian tube was first defined from a meta-analysis of published proteomic datasets that identified 190 ECM proteins. We then conducted de novo proteomics using ECM enrichment and identified 88 proteins, 7 of which were not identified in prior studies (COL2A1, COL4A5, COL16A1, elastin, LAMA5, annexin A2, and PAI1). To enable future in vitro studies, we investigated the levels and localization of ECM components included in tissue-engineered models (type I, III, and IV collagens, fibronectin, laminin, versican, perlecan, and hyaluronic acid) using multispectral immunohistochemical staining of fimbriae from patients with benign conditions or STICs. Quantification revealed an increase in stromal fibronectin and a decrease in epithelial versican in STICs. Our results provide an in-depth picture of the ECM in the benign fallopian tube and identified ECM changes that accompany STIC formation. (J Histochem Cytochem XX: XXX–XXX, XXXX) [ABSTRACT FROM AUTHOR]

Arrhythmogenic cardiomyopathy (AC) is a primarily autosomal-dominant cardiomyopathy resulting from defects of desmosomal proteins that would normally provide structural integrity to cardiomyocytes. (1) The incidence is frequently cited as 1 [...], Arrhythmogenic cardiomyopathy (AC) has traditionally been regarded as a rare disease with variably penetrant autosomal-dominant inheritance. Recent years have revealed that AC is actually a spectrum of disease with prevalence much higher than previously thought. Diagnosis can be quite challenging because of highly variable clinical presentation, even among family members sharing a mutation. Unlike other cardiomyopathies, AC has a concealed phase during which patients have arrhythmias in the absence of structural heart disease but remain at risk of sudden cardiac death. Importantly, it is in the setting of sudden cardiac death that pathologists are most likely to encounter AC. It is critical that these findings not be overlooked, as family members of the deceased may also be affected and could potentially avoid such a dismal outcome. With time, advances in ancillary studies are likely to expand the role for pathologists in AC diagnosis. (Arch Pathol Lab Med. 2015; 139:1181-1186; doi: 10.5858/arpa.2014-0114-RS)

Unpacking paclitaxel response: Paclitaxel is a common treatment for many cancers, although not all patients benefit from the treatment and the mechanism by which it works is unclear. Here, Scribano et al. studied patients with breast cancer undergoing paclitaxel treatment as part of a clinical trial to elucidate the drug's mechanism of action, demonstrating that paclitaxel treatment increased cell division with chromosome missegregation to induce cytotoxicity. They also found that increased chromosomal instability in tumor cells before treatment was predictive of response to taxane therapy. Although the findings require further validation, this increased chromosomal instability may serve as a predictive biomarker for paclitaxel response in patients with breast cancer. Paclitaxel (Taxol) is a cornerstone of cancer treatment. However, its mechanism of cytotoxicity is incompletely understood and not all patients benefit from treatment. We show that patients with breast cancer did not accumulate sufficient intratumoral paclitaxel to induce mitotic arrest in tumor cells. Instead, clinically relevant concentrations induced multipolar mitotic spindle formation. However, the extent of early multipolarity did not predict patient response. Whereas multipolar divisions frequently led to cell death, multipolar spindles focused into bipolar spindles before division at variable frequency, and maintaining multipolarity throughout mitosis was critical to induce the high rates of chromosomal instability necessary for paclitaxel to elicit cell death. Increasing multipolar divisions in paclitaxel resulted in improved cytotoxicity. Conversely, decreasing paclitaxel-induced multipolar divisions reduced paclitaxel efficacy. Moreover, we found that preexisting chromosomal instability sensitized breast cancer cells to paclitaxel. Both genetic and pharmacological methods of inducing chromosomal instability were sufficient to increase paclitaxel efficacy. In patients, the amount of pretreatment chromosomal instability directly correlated with taxane response in metastatic breast cancer such that patients with a higher rate of preexisting chromosomal instability showed improved response to taxanes. Together, these results support the use of baseline rates of chromosomal instability as a predictive biomarker for paclitaxel response. Furthermore, they suggest that agents that increase chromosomal instability or maintain multipolar spindles throughout mitosis will improve the clinical utility of paclitaxel. [ABSTRACT FROM AUTHOR]

New tools are needed to match cancer patients with effective treatments. Patient-derived organoids offer a high-throughput platform to personalize treatments and discover novel therapies. Currently, methods to evaluate drug response in organoids are limited because they overlook cellular heterogeneity. In this study, non-invasive optical metabolic imaging (OMI) of cellular heterogeneity was characterized in breast cancer (BC) and pancreatic cancer (PC) patient-derived organoids. Baseline heterogeneity was analyzed for each patient, demonstrating that single-cell techniques, such as OMI, are required to capture the complete picture of heterogeneity present in a sample. Treatment-induced changes in heterogeneity were also analyzed, further demonstrating that these measurements greatly complement current techniques that only gauge average cellular response. Finally, OMI of cellular heterogeneity in organoids was evaluated as a predictor of clinical treatment response for the first time. Organoids were treated with the same drugs as the patient's prescribed regimen, and OMI measurements of heterogeneity were compared to patient outcome. OMI distinguished subpopulations of cells with divergent and dynamic responses to treatment in living organoids without the use of labels or dyes. OMI of organoids agreed with long-term therapeutic response in patients. With these capabilities, OMI could serve as a sensitive high-throughput tool to identify optimal therapies for individual patients, and to develop new effective therapies that address cellular heterogeneity in cancer. [ABSTRACT FROM AUTHOR]

• When used in combination, SOX10 and GATA3 detect nearly all mammary carcinomas. • Though regarded as a marker of triple negative breast cancer, SOX10 is also frequently expressed when ER expression is low. • SOX10 co-expression may be useful for cases with weak GATA3 expression in establishing a breast primary. The complementary coverage of different subsets of breast cancer by GATA3 and SOX10 makes their use in combination appealing for routine clinical use, but study of these markers has been largely limited to cases with high or absent ER expression. Here we report SOX10 and GATA3 immunostaining in parallel using a tissue microarray containing 246 invasive breast carcinoma cases with a range of ER expression. GATA3 and SOX10 were positive in 93 % (229/246) and 15 % (38/246) of cases overall and in 63 % (24/38) and 74 % (28/38) of triple negative breast carcinomas (TNBC), respectively; SOX10 was positive in 15 of the 17 cases that lacked GATA3 expression (88 %). SOX10 was also positive in 3 % (6/196) of ER + cases, including 50 % of cases with low ER (3/6), 20 % with intermediate ER (3/15), and 0 % with high ER (n = 175), so that ER-low cases more strongly resembled TNBC than those with high ER expression. GATA3 expression was lower in cases that co-expressed SOX10 in comparison to those that were positive for GATA3 alone. Less than 1 % (2/246) of cases were negative for both GATA3 and SOX10. Therefore, SOX10 is a useful adjunct to GATA3 in the detection of TNBC and cases with low ER expression and/or reduced GATA3 intensity relative to that typical of breast cancers with higher ER expression. Moreover, given such high sensitivity, metastatic tumors lacking either GATA3 or SOX10 are unlikely to be of breast origin. Additional study is necessary to determine the extent to which SOX10 may also improve specificity and to characterize its biologic significance in breast cancers with low ER expression. [ABSTRACT FROM AUTHOR]

Invasive breast carcinomas (IBC) that strongly express SOX10 are almost always negative for androgen receptor (AR). Furthermore, this SOX10+/AR- subset of IBC is nearly always estrogen receptor and progesterone receptor negative (ER-/PR-), being most commonly seen in triple negative breast carcinomas (TNBC), but also in a small subset of HER2+/ER-/PR- IBC. Following our previous work demonstrating the expression of SOX10 in a subset of IBC with "low positive" ER expression (i.e. 1–10 % ER+ staining based on CAP guidelines, here referred to as "ER-low"), we sought to investigate the expression of both SOX10 and AR in a larger cohort of ER-low tumors. As our previous work also revealed occasional SOX10 expression in IBC with >10 % ER+ staining, we also included tumors with any percentage of ER staining, as long as the staining intensity was weak (this subset is referred to as "ER-weak"). We screened cases of HER2-/ER+ IBC diagnosed at our institution over a 10 year period, identified both ER-low and ER-weak tumors and stained both groups with SOX10 and AR. Strong SOX10 expression was seen in 12/25 (48 %) ER-low tumors and 13/24 (54 %) ER-weak tumors. ER staining in the SOX10+ subset of ER-weak tumors ranged from 15 %−80 % (median 25 %). As expected, AR was negative in all but 1 of the SOX10+ tumors in both groups. While case numbers in these groups were too small for a meaningful statistical analysis, we did note that all SOX10+/AR- tumors within both the ER-low and ER-weak groups were histologic grade 3. The presence of a SOX10+/AR- profile in a significant subset of ER-low tumors confirms the findings of our previous work and provides further support for the proposed functionally ER negative status of this group. Furthermore, the fact that the same SOX10+/AR- profile is seen in a roughly equal subset of ER-weak tumors suggests that a wider range of ER staining may be acceptable as "low positive" in SOX10+/AR- tumors, as long as the ER staining is of weak intensity. However, given the small number of cases in this single institution study, we emphasize the need for larger studies to establish the biological and clinical significance of this tumor subset. [ABSTRACT FROM AUTHOR]

Significance: A deep learning model, trained using transcriptomic data, inexpensively quantifies and fine-maps ITH due to subtype admixture in routine images of LumA breast cancer, the most favorable subtype. This new approach could facilitate exploration of the mechanisms behind such heterogeneity and its impact on selection of therapy for individual patients., (©2024 The Authors; Published by the American Association for Cancer Research.)

Objectives: The current recommendation for hysterectomy specimens performed for cervical cancer following conization is that the entire cervix be submitted for histologic examination. Given the high cost of medical procedures and concerns regarding difficulties with laboratory staffing, we sought to evaluate the potential for selective histologic examination in this setting., Methods: Post-conization hysterectomy cases were reviewed for the presence of residual disease in relation to the findings of the prior conization, with consideration of margin status. Residual disease was then assessed for clinical significance. The number of submitted blocks was recorded and the associated costs were estimated., Results: Among 32 cases with invasive carcinoma, only cases with margins positive for invasive carcinoma on the conization specimen had residual invasion in the hysterectomy (n = 7), and there were no upgrades due to subtle microscopic disease; 1 case had a change in pathologic stage from pT1b1 to pT2b due to parametrial involvement in the setting of a grossly apparent lesion. Among 20 cases performed following a diagnosis of dysplasia, none were upgraded to invasive carcinoma. Based on protocol-based submission of the entire cervix, 16 blocks of cervix were submitted on average (range, 4-41)., Conclusions: We estimate that representative sections from each cervical quadrant would save approximately 2 work hours for laboratory staff per case and up to 6 hours for larger cases, reducing costs for the laboratory accordingly. Selective cervical sampling in the setting of negative margins on conization provides an opportunity for improved resource utilization without compromising patient care; as this is a small study, confirmation of these findings in a larger number of cases may be warranted. Additional studies are necessary to determine what other contexts in surgical pathology could benefit from a similar reductive approach., (© The Author(s) 2024. Published by Oxford University Press on behalf of American Society for Clinical Pathology. All rights reserved. For commercial re-use, please contact reprints@oup.com for reprints and translation rights for reprints. All other permissions can be obtained through our RightsLink service via the Permissions link on the article page on our site—for further information please contact journals.permissions@oup.com.)

Human papillomaviruses (HPVs) are the most common sexually transmitted infection in the United States and are a major etiological agent of cancers in the anogenital tract and oral cavity. Growing evidence suggests changes in the host microbiome are associated with the natural history and ultimate outcome of HPV infection. We sought to define changes in the host cervicovaginal microbiome during papillomavirus infection, persistence, and pathogenesis using the murine papillomavirus (MmuPV1) cervicovaginal infection model. Cervicovaginal lavages were performed over a time course of MmuPV1 infection in immunocompetent female FVB/N mice and extracted DNA was analyzed by qPCR to track MmuPV1 viral copy number. 16S ribosomal RNA (rRNA) gene sequencing was used to determine the composition and diversity of microbial communities throughout this time course. We also sought to determine whether specific microbial communities exist across the spectrum of MmuPV1-induced neoplastic disease. We, therefore, performed laser-capture microdissection to isolate regions of disease representing all stages of neoplastic disease progression (normal, low- and high-grade dysplasia, and cancer) from female reproductive tract tissue sections from MmuPV1-infected mice and performed 16S rRNA sequencing. Consistent with other studies, we found that the natural murine cervicovaginal microbiome is highly variable across different experiments. Despite these differences in initial microbiome composition between experiments, we observed that MmuPV1 persistence, viral load, and severity of disease influenced the composition of the cervicovaginal microbiome. These studies demonstrate that papillomavirus infection can alter the cervicovaginal microbiome.IMPORTANCEHuman papillomaviruses (HPVs) are the most common sexually transmitted infection in the United States. A subset of HPVs that infect the anogenital tract (cervix, vagina, anus) and oral cavity cause at least 5% of cancers worldwide. Recent evidence indicates that the community of microbial organisms present in the human cervix and vagina, known as the cervicovaginal microbiome, plays a role in HPV-induced cervical cancer. However, the mechanisms underlying this interplay are not well-defined. In this study, we infected the female reproductive tract of mice with a murine papillomavirus (MmuPV1) and found that key aspects of papillomavirus infection and disease influence the host cervicovaginal microbiome. This is the first study to define changes in the host microbiome associated with MmuPV1 infection in a preclinical animal model of HPV-induced cervical cancer. These results pave the way for using MmuPV1 infection models to further investigate the interactions between papillomaviruses and the host microbiome., Competing Interests: The authors declare no conflict of interest.

Competing Interests: The authors declare no conflict of interest.

Chromosomal instability (CIN), the persistent reshuffling of chromosomes during mitosis, is a hallmark of human cancers that contributes to tumor heterogeneity and has been implicated in driving metastasis and altering responses to therapy. Though multiple mechanisms can produce CIN, lagging chromosomes generated from abnormal merotelic attachments are the major cause of CIN in a variety of cell lines, and are expected to predominate in cancer. Here, we quantify CIN in breast cancer using a tumor microarray, matched primary and metastatic samples, and patient-derived organoids from primary breast cancer. Surprisingly, misaligned chromosomes are more common than lagging chromosomes and represent a major source of CIN in primary and metastatic tumors. This feature of breast cancers is conserved in a majority of breast cancer cell lines. Importantly, though a portion of misaligned chromosomes align before anaphase onset, the fraction that remain represents the largest source of CIN in these cells. Metastatic breast cancers exhibit higher rates of CIN than matched primary cancers, primarily due to increases in misaligned chromosomes. Whether CIN causes immune activation or evasion is controversial. We find that misaligned chromosomes result in immune-activating micronuclei substantially less frequently than lagging and bridge chromosomes and that breast cancers with greater frequencies of lagging chromosomes and chromosome bridges recruit more stromal tumor-infiltrating lymphocytes. These data indicate misaligned chromosomes represent a major mechanism of CIN in breast cancer and provide support for differential immunostimulatory effects of specific types of CIN., Significance: We surveyed the single-cell landscape of mitotic defects that generate CIN in primary and metastatic breast cancer and relevant models. Misaligned chromosomes predominate, and are less immunostimulatory than other chromosome segregation errors., Competing Interests: J.B. Tucker reports grants from NIH during the conduct of the study. S.C. Bonema reports grants from NIH during the conduct of the study. M.E. Burkard reports grants from NCI and National Institute for General Medical Sciences during the conduct of the study; personal fees from Springer Nature and Novartis; grants and personal fees from Strata Oncology; grants from Abbvie, Arcus, Apollomics, Elevation Oncology, Endeavor, Genentech, Puma, Loxo Oncology/Lilly, Seagen outside the submitted work; in addition, M.E. Burkard has a patent to 14/727399 issued, a patent to US20200157531 issued, and a patent to P200189US01 issued. B.A. Weaver reports grants from NIH and DOD during the conduct of the study. No disclosures were reported by the other authors., (© 2023 The Authors; Published by the American Association for Cancer Research.)

Female SV40 C3(1) T-antigen (C3(1)/TAg) transgenic mice develop mammary tumors that are molecularly similar to human basal-like breast cancers with 100% incidence at 16 weeks of age. To determine the requirement for growth hormone (GH) signaling in these tumors, genetic crosses were used to create cohorts of female mice that were homozygous for a floxed growth hormone receptor (Ghr) gene and carried one copy each of the Rosa-Cre-ERT2 transgene and the C3(1)/TAg transgene (Ghrflox/flox; Rosa-Cre-ERT2; C3(1)/TAg+/0 mice). When the largest mammary tumor reached 200 mm3, mice were treated with tamoxifen to delete Ghr or with vehicle as a control. An additional group of Ghrflox/flox; C3(1)/TAg+/0 mice were also treated with tamoxifen when the largest mammary tumor reached 200 mm3 as a control for the effects of tamoxifen. After 3 weeks, tumors in mice in which Ghr was deleted began to shrink while vehicle and tamoxifen treatment control mouse tumors continued to grow. Pathological analysis of tumors revealed similar growth patterns and varying levels of necrosis throughout all groups. A decrease in cancer cell proliferation in Ghr-/- tumors relative to controls was observed as measured by Ki67 immunohistochemistry labeling index. These data suggest that even established C3(1)/TAg mammary tumors are dependent on the GH/IGF-1 axis., (© The Author(s) 2022. Published by Oxford University Press on behalf of the Endocrine Society. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

There is increasing evidence that many endometrial cancers (EC) diagnosed as clear cell carcinoma (CCC) have substantial overlap with both serous carcinoma (SC) and endometrioid carcinoma (EmC), not only in terms of morphology and immunophenotype but also by molecular characterization. Now with use of HER2-based therapy in SC, a CCC diagnosis in serous-like tumors has the potential to exclude patients from receiving beneficial therapy. To assess HER2 in CCC in relation to other characteristics, a tissue microarray of archived CCC, EmC, and SC was stained for HER2 alongside a battery of immunostains used in EC. Cases with equivocal HER2 IHC were also assessed by in situ hybridization. HER2 status was assessed in 229 cases (23 CCC, 74 SC, 132 EmC). HER2 was positive in 48% of cases diagnosed as CCC, 19% of SC, and 0% of EmC. Rigorous morphologic and immunophenotypic review by 5 gynecologic pathologists revealed diagnostic disagreement in 8/11 HER2+ cases diagnosed as CCC, with SC as the other major diagnostic consideration. All HER2+ (n=25) cases were MMR-intact and most HER2+ EC had aberrant p53 staining (22/25, 88%); the 3 cases with a wild type pattern for p53 (12%) were all negative for ER. Based on these findings, patients with a diagnosis of CCC should be included in future clinical trials of HER2-targeted therapy. Moreover, given the diagnostic difficulty surrounding CCC, immunohistochemistry-based algorithms that include aberrant p53 and/or the absence of ER expression may provide a more objective means of establishing eligibility criteria than is currently possible using traditional histologic classification., Competing Interests: The authors declare no conflict of interest., (Copyright © 2021 by the International Society of Gynecological Pathologists.)

Optimal use of human tissue for research requires an understanding of basic pathologic principles. Given that the physical assessment of tissue must occur as part of standard clinical examination, it cannot be handled directly by investigators unless they are also a part of the care team. The purpose of this chapter is to provide an overview of the clinical analytic process, from initial gross handling to histologic examination by light microscopy and the use of ancillary studies, in order to provide context for samples that are used in research and to highlight specific considerations that are relevant for obtaining appropriate tissue for experimental purposes. Given that they comprise >95% of ovarian malignancies, there is an emphasis on epithelial tumors., (© 2022. The Author(s), under exclusive license to Springer Science+Business Media, LLC, part of Springer Nature.)

Taxanes remain one of the most effective medical treatments for breast cancer. Clinical trials have coupled taxanes with immune checkpoint inhibitors in patients with triple-negative breast cancer (TNBC) with promising results. However, the mechanism linking taxanes to immune activation is unclear. To determine if paclitaxel could elicit an antitumoral immune response, we sampled tumor tissues from patients with TNBC receiving weekly paclitaxel (80 mg/m 2 ) and found increased stromal tumor-infiltrating lymphocytes and micronucleation over baseline in three of six samples. At clinically relevant concentrations, paclitaxel can induce chromosome missegregation on multipolar spindles during mitosis. Consequently, post-mitotic cells are multinucleated and contain micronuclei, which often activate cyclic GMP-AMP synthase (cGAS) and may induce a type I IFN response reliant on the stimulator of IFN genes (STING) pathway. Other microtubule-targeting agents, eribulin and vinorelbine, recapitulate this cGAS/STING response and increased the expression of immune checkpoint molecule, PD-L1, in TNBC cell lines. To test the possibility that microtubule-targeting agents sensitize tumors that express cGAS to immune checkpoint inhibitors, we identified 10 patients with TNBC treated with PD-L1 or PD-1, seven of whom also received microtubule-targeting agents. Elevated baseline cGAS expression significantly correlated with treatment response in patients receiving microtubule-targeting agents in combination with immune checkpoint inhibitors. Our study identifies a mechanism by which microtubule-targeting agents can potentiate an immune response in TNBC. Further, baseline cGAS expression may predict patient treatment response to therapies combining microtubule-targeting agents and immune checkpoint inhibitors., (©2021 American Association for Cancer Research.)

Objective: Progestin-based therapy is common for patients with endometrial neoplasia who desire fertility preservation, but some patients ultimately require surgery. Intraoperative assessment, which can use gross lesion size, may impact the extent of surgery performed. We sought to characterize the extent to which grossly identified lesions in the setting of progestin therapy correspond to microscopic findings., Methods: Thirteen hysterectomy specimens with progestin-treated atypical hyperplasia or endometrioid carcinoma were identified. Clinicopathologic factors were collected by chart review. Slides were assessed for the extent to which decidualized stroma (DS) comprised grossly identified lesions and comparisons were drawn with tumor size, age, and menopausal status., Results: Mass lesions were described in 11 cases with a median of 4.5 cm (range 1-8.2) and the 2 cases without discrete masses had diffuse thickening. Two patients had only focal residual hyperplasia despite having mass lesions (7 & 2.2 cm). DS was more prominent in premenopausal patients (median 65%, range 10-90%) than in postmenopausal patients (median 18%, range 10-40%; p = 0.06). The distribution of DS throughout mass lesions was variable., Conclusions: Large mass lesions following progestin therapy may histologically consist of DS with little to no residual neoplastic disease, such that perceived tumor size does not necessarily reflect extensive residual disease, especially in pre-menopausal patients. Intraoperative gross assessment alone may lead to unnecessary lymphadenectomy and/or oophorectomy, but this can potentially be prevented by using frozen section., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2021 The Authors. Published by Elsevier Inc.)

The role of phospholipid signaling in ovarian cancer is poorly understood. Sphingosine-1-phosphate (S1P) is a bioactive metabolite of sphingosine that has been associated with tumor progression through enhanced cell proliferation and motility. Similarly, sphingosine kinases (SPHK), which catalyze the formation of S1P and thus regulate the sphingolipid rheostat, have been reported to promote tumor growth in a variety of cancers. The findings reported here show that exogenous S1P or overexpression of SPHK1 increased proliferation, migration, invasion, and stem-like phenotypes in ovarian cancer cell lines. Likewise, overexpression of SPHK1 markedly enhanced tumor growth in a xenograft model of ovarian cancer, which was associated with elevation of key markers of proliferation and stemness. The diabetes drug, metformin, has been shown to have anticancer effects. Here, we found that ovarian cancer patients taking metformin had significantly reduced serum S1P levels, a finding that was recapitulated when ovarian cancer cells were treated with metformin and analyzed by lipidomics. These findings suggested that in cancer the sphingolipid rheostat may be a novel metabolic target of metformin. In support of this, metformin blocked hypoxia-induced SPHK1, which was associated with inhibited nuclear translocation and transcriptional activity of hypoxia-inducible factors (HIF1α and HIF2α). Further, ovarian cancer cells with high SPHK1 were found to be highly sensitive to the cytotoxic effects of metformin, whereas ovarian cancer cells with low SPHK1 were resistant. Together, the findings reported here show that hypoxia-induced SPHK1 expression and downstream S1P signaling promote ovarian cancer progression and that tumors with high expression of SPHK1 or S1P levels might have increased sensitivity to the cytotoxic effects of metformin. IMPLICATIONS: Metformin targets sphingolipid metabolism through inhibiting SPHK1, thereby impeding ovarian cancer cell migration, proliferation, and self-renewal., (©2019 American Association for Cancer Research.)

Papillomaviruses exhibit species-specific tropism, thereby limiting understanding and research of several aspects of HPV infection and carcinogenesis. The discovery of a murine papillomavirus (MmuPV1) provides the opportunity to study papillomavirus infections in a tractable, in vivo laboratory model. MmuPV1 infects and causes disease in the cutaneous epithelium, as well as the mucosal epithelia of the oral cavity and anogenital tract. In this report, we describe a murine model of MmuPV1 infection and neoplastic disease in the female reproductive tracts of wild-type immunocompetent FVB mice. Low-grade dysplastic lesions developed in reproductive tracts of FVB mice infected with MmuPV1 for 4 months, and mice infected for 6 months developed significantly worse disease, including squamous cell carcinoma (SCC). We also tested the contribution of estrogen and/or UV radiation (UVR), two cofactors we previously identified as being involved in papillomavirus-mediated disease, to cervicovaginal disease. Similar to HPV16 transgenic mice, exogenous estrogen treatment induced high-grade precancerous lesions in the reproductive tracts of MmuPV1-infected mice by 4 months and together with MmuPV1 efficiently induced SCC by 6 months. UV radiation and exogenous estrogen cooperated to promote carcinogenesis in MmuPV1-infected mice. This murine infection model represents the first instance of de novo papillomavirus-mediated carcinogenesis in the female reproductive tract of wild-type mice resulting from active virus infection and is also the first report of the female hormone estrogen contributing to this process. This model will provide an additional platform for fundamental studies on papillomavirus infection, cervicovaginal disease, and the role of cellular cofactors during papillomavirus-induced carcinogenesis. IMPORTANCE Tractable and efficient models of papillomavirus-induced pathogenesis are limited due to the strict species-specific and tissue-specific tropism of these viruses. Here, we report a novel preclinical murine model of papillomavirus-induced cervicovaginal disease in wild-type, immunocompetent mice using the recently discovered murine papillomavirus, MmuPV1. In this model, MmuPV1 establishes persistent viral infections in the mucosal epithelia of the female reproductive tract, a necessary component needed to accurately mimic HPV-mediated neoplastic disease in humans. Persistent MmuPV1 infections were able to induce progressive neoplastic disease and carcinogenesis, either alone or in combination with previously identified cofactors of papillomavirus-induced disease. This new model will provide a much-needed platform for basic and translational studies on both papillomavirus infection and associated disease in immunocompetent mice., (Copyright © 2019 Spurgeon et al.)

Mutations in the breast cancer susceptibility gene 1 ( BRCA1 ) are associated with an increased risk of developing epithelial ovarian cancer. However, beyond the role of BRCA1 in DNA repair, little is known about other mechanisms by which BRCA1 impairment promotes carcinogenesis. Given that altered metabolism is now recognized as important in the initiation and progression of cancer, we asked whether the loss of BRCA1 changes metabolism in the cells of origin of ovarian cancer. The findings show that silencing BRCA1 in ovarian surface epithelial and fallopian tube cells increased glycolysis. Furthermore, when these cells were transfected with plasmids carrying deleterious BRCA1 mutations (5382insC or the P1749R), there was an increase in hexokinase-2 (HK2), a key glycolytic enzyme. This effect was mediated by MYC and the STAT3. To target the metabolic phenotype induced by loss of BRCA1, a drug-repurposing approach was used and aspirin was identified as an agent that counteracted the increase in HK2 and the increase in glycolysis induced by BRCA1 impairment. Evidence from this study indicates that the tumor suppressor functions of BRCA1 extend beyond DNA repair to include metabolic endpoints and identifies aspirin as an ovarian cancer chemopreventive agent capable of reversing the metabolic derangements caused by loss of BRCA1. Cancer Prev Res; 10(4); 255-66. ©2017 AACR ., (©2016 American Association for Cancer Research.)

Aim: To describe the clinicopathologic features of concurrent polyomavirus nephropathy (PVN) and endarteritis due to rejection in renal allografts., Methods: We searched our electronic records database for cases with transplant kidney biopsies demonstrating features of both PVN and acute rejection (AR). PVN was defined by the presence of typical viral cytopathic effect on routine sections and positive polyomavirus SV40 large-T antigen immunohistochemistry. AR was identified by endarteritis (v1 by Banff criteria). All cases were subjected to chart review in order to determine clinical presentation, treatment course and outcomes. Outcomes were recorded with a length of follow-up of at least one year or time to nephrectomy., Results: Of 94 renal allograft recipients who developed PVN over an 11-year period at our institution, we identified 7 (7.4%) with viral cytopathic changes, SV40 large T antigen staining, and endarteritis in the same biopsy specimen, indicative of concurrent PVN and AR. Four arose after reduction of immunosuppression (IS) (for treatment of PVN in 3 and tuberculosis in 1), and 3 patients had no decrease of IS before developing simultaneous concurrent disease. Treatment consisted of reduced oral IS and leflunomide for PVN, and anti-rejection therapy. Three of 4 patients who developed endarteritis in the setting of reduced IS lost their grafts to rejection. All 3 patients with simultaneous PVN and endarteritis cleared viremia and were stable at 1 year of follow up. Patients with endarteritis and PVN arising in a background of reduced IS had more severe rejection and poorer outcome., Conclusion: Concurrent PVN and endarteritis may be more frequent than is currently appreciated and may occur with or without prior reduction of IS.