Dysregulated gene subnetworks in breast invasive carcinoma reveal novel tumor suppressor genes.

Breast invasive carcinoma (BRCA) is the most malignant and leading cause of death in women. Global efforts are ongoing for improvement in early detection, prevention, and treatment. In this milieu, a comprehensive analysis of RNA-sequencing data of 1097 BRCA samples and 114 normal adjacent tissues is done to identify dysregulated genes in major molecular classes of BRCA in various clinical stages. Significantly enriched pathways in distinct molecular classes of BRCA have been identified. Pathways such as interferon signaling, tryptophan degradation, granulocyte adhesion & diapedesis, and catecholamine biosynthesis were found to be significantly enriched in Estrogen/Progesterone Receptor positive/Human Epidermal Growth Factor Receptor 2 negative, pathways such as RAR activation, adipogenesis, the role of JAK1/2 in interferon signaling, TGF-ß and STAT3 signaling intricated in Estrogen/Progesterone Receptor negative/Human Epidermal Growth Factor Receptor 2 positive and pathways as IL-1/IL-8, TNFR1/TNFR2, TWEAK, and relaxin signaling were found in triple-negative breast cancer. The dysregulated genes were clustered based on their mutation frequency which revealed nine mutated clusters, some of which were well characterized in cancer while others were less characterized. Each cluster was analyzed in detail which led to the identification of NLGN3, MAML2, TTN, SYNE1, ANK2 as candidate genes in BRCA. They are central hubs in the protein-protein-interaction network, indicating their important regulatory roles. Experimentally, the Real-Time Quantitative Reverse Transcription PCR and western blot confirmed our computational predictions in cell lines. Further, immunohistochemistry corroborated the results in ~ 100 tissue samples. We could experimentally show that the NLGN3 & ANK2 have tumor-suppressor roles in BRCA as shown by cell viability assay, transwell migration, colony forming and wound healing assay. The cell viability and migration was found to be significantly reduced in MCF7 and MDA-MB-231 cell lines in which the selected genes were over-expressed as compared to control cell lines. The wound healing assay also demonstrated a significant decrease in wound closure at 12 h and 24 h time intervals in MCF7 & MDA-MB-231 cells. These findings established the tumor suppressor roles of NLGN3 & ANK2 in BRCA. This will have important ramifications for the therapeutics discovery against BRCA.

Diminution of Primary Cilia in the Stromal Cells at the Tumor-stromal Interface Correlates With an Aggressive Tumor Biology in the Urothelial Carcinoma of the Urinary Bladder.

BACKGROUND AND AIMS: Primary cilia (PC) are cellular organelles that regulate the cellular homeostasis. They are the seats of many oncogenic pathways and indirectly regulate the epithelial-mesenchymal transition (EMT) and extracellular matrix, both critical for the tumor microenvironment (TME). Though there are a few studies highlighting the alteration of PC in the tumor cells of various malignancies, none depict the PC in the stromal cells in the urothelial carcinoma of the urinary bladder (UC), the stromal cells being an essential component of TME. Therefore, we intend to evaluate the PC in the stromal cells at the tumor-stromal interface in UC. METHODS: Immunohistochemistry for acetylated-α-tubulin (for PC), Ki67, E-cadherin, and SNAI1 was performed in 141 cases of UC and 5 normal controls, and primary cilium: nucleus (C:N) ratio was counted in the stromal cells at the tumor-stromal interface. The C:N ratio was correlated with various clinical and histopathological parameters. RESULTS: The C:N ratio showed significant diminution from normal control (mean=0.75) to low-grade UC (mean=0.24) ( P =0.001) to high-grade UC (mean value=0.17) ( P =0.001). There was a significant diminution of the C:N ratio from the noninvasive to invasive UC ( P =0.025). The C:N ratio did not show any correlation with EMT although negatively correlated with the Ki67 index ( r =-0.32; P =0.001), and a higher ratio showed a trend with a higher recurrence-free survival ( P =0.07). CONCLUSIONS: The diminution of the PC in the stromal cells at the tumor-stromal interface is an early event and correlates with an aggressive tumor biology of UC.

CK7+/CK20+/CDX2+ mucinous carcinoma, arising in a mature cystic teratoma of ovary, presenting with disseminated metastasis and pseudomyxoma peritonei.

ABSTRACT: Mucinous carcinomas arising within an ovarian dermoid tumor are rare. Most of the cases reported in the literature show morphological features resembling an appendiceal mucinous neoplasm. They exhibit CK7-/CK20+ immunophenotype similar to carcinomas of the lower gastrointestinal tract. In this report, we have described a case of a well-differentiated mucinous carcinoma arising within a mature cystic teratoma. The mucinous carcinoma showed a spectrum of morphological patterns, including cystadenoma-like areas, proliferative/borderline areas, villous adenoma-like areas, and areas of invasive carcinoma. In addition, our case showed some unusual findings, namely, diffuse CK7 positivity, associated pseudomyxoma peritonei, and metastasis to lungs. These features were not demonstrated in any of the previously reported cases. Our case shows that the teratomatous mucinous neoplasm of the ovary may show CK7+/CK20+/CDX2 + immunoprofile making it immunohistochemically indistinguishable from a primary ovarian mucinous neoplasm or a metastatic mucinous carcinoma of the lower gastrointestinal tract.

Expression of EZH2 and H3K27me3 predicts tumor biology of urothelial carcinoma.

Background: Enhancer of zeste homolog 2 (EZH2) is one of the major epigenetic modifiers involved in the transcriptional repression of target genes through trimethylation of H3K27 (lysine 27 residue of histone H3). Deregulated expression of both EZH2 and H3K27me3 has been implicated in the biological behavior and prognostic outcome of various malignancies. Aim: To assess the role of EZH2 and H3K27me3 in the carcinogenesis of urothelial carcinoma of urinary bladder. Materials and Methods: One hundred fifty consecutive urothelial carcinoma cases of urinary bladder (54.7% high-grade) were included in this study. Immunohistochemical analysis for EZH2 and H3K27me3 was performed on whole tissue sections. A multiplication score obtained by multiplying staining intensity and proportion of positively stained neoplastic cells was used for assessment. Results: EZH2 showed a significant correlation with the tumor grade and lamina propria invasion (p < 0.001). The cases with high EZH2 expression showed a significantly high proliferative index (Mean- 32.7%; p < 0.001). In contrast, negative and low expression of H3K27me3 was significantly more common in high-grade cases (p = 0.006). The expression of H3K27me3 was significantly associated with lamina propria (p = 0.01) and deep muscle invasion (p = 0.007). EZH2 showed a significantly higher expression in the high-grade invasive areas as compared to the high-grade non-invasive areas of the same tumor (p = 0.03). Conclusions: This study establishes an important role of the key epigenetic regulators EZH2 and H3K27me3 in the pathobiology of urothelial carcinomas. Strong expression of EZH2 and weak expression of H3K27me3 are associated with higher grade, proliferative index and invasive behavior.

The rhabdoid variant of adrenocortical carcinoma-Report of three cases and literature review.

Adrenocortical carcinoma (ACC) is a rare and aggressive malignancy. Extensive rhabdoid morphology in ACC has been described recently in very few cases. The proportion of rhabdoid morphology and the role of SMARCB1/ INI1 expression in these tumor cells to diagnose the specific variant is not described in the literature. We reviewed the clinicopathological features of nine cases of adrenocortical neoplasm. Out of which, three cases of ACC showed predominant rhabdoid morphology. Large discohesive cells with abundant cytoplasm containing eosinophilic inclusions, eccentric vesicular nucleus, and prominent nucleoli. INI1 immunostain was retained in all cases. We reported the rhabdoid variant of ACC, a novel entity, and its diagnostic approach from their histological mimickers. Identifying more cases of this entity will help to clearly understand the pathogenesis, biologic behaviour, and any specific molecular alterations in the future.

G-protein-coupled receptor 141 mediates breast cancer proliferation and metastasis by regulating oncogenic mediators and the p-mTOR/p53 axis.

Breast cancer morbidity is surging towards the peak in females across the globe. An inherent property of cancer cells is enhanced cell proliferation rate and migration capability, leading to deregulated cell signaling cascades. G-protein-coupled receptors (GPCRs) have recently emerged as a hot-spot target in cancer research. We identify aberrant expression of G-protein-coupled receptor 141 (GPR141) in different breast cancer subtypes that correlate with poor prognosis. However, the molecular mechanism via which GPR141 advances breast cancer remains elusive. Increased GPR141 expression enhances the migratory behavior of breast cancer, driving oncogenic pathways both in vitro and in vivo through activation of epithelial to mesenchymal transition (EMT), oncogenic mediators and regulation of p-mTOR/p53 signaling. Our study unveils a molecular mechanism for p53 downregulation and activation of p-mTOR1 and its substrates in GPR141 overexpressed cells, accelerating breast tumorigenesis. We find that an E3 ubiquitin ligase, Cullin1, partly mediates p53 degradation via proteasomal pathway. Co-immunoprecipitation result shows that the phosphorylated form of 40S ribosome protein S6 (ps6., a p-mTOR1 substrate) forms a complex with Cullin1. These findings suggest an interplay between Cullin1 and p-mTOR1 in GPR141 overexpressed cells that downregulates p53 expression, thus inducing tumor growth. GPR141 silencing restores p53 expression and attenuates p-mTOR1 signaling events, thereby impeding proliferation and migration in breast cancer cells. Our findings describe the role of GPR141 in breast cancer proliferation, and metastasis, as well as in influencing the tumor microenvironment. Modulating GPR141 expression could pave the way for a better therapeutic approach to regulating breast cancer progression and metastasis.

Metronomic Therapy in Palliation of Oral Cancer Patients-A Home Based Approach at the End of Life.

INTRODUCTION: Despite the development of targeted therapies for the management of oral cancer patients, the cost of treatment is a concern in middle- and low-income countries. The present study assessed the feasibility of low-cost metronomic therapy as an alternative treatment modality in patients with unresectable or inoperable oral cancers. METHODOLOGY: The study was a prospective, single-arm study. Unresectable, inoperable, and metastatic lip and oral cavity cancers were started on metronomic therapy, a combination of oral methotrexate 15 mg/m2 once a week and oral celecoxib 200 mg twice daily, as palliative therapy. The primary endpoint was overall survival. The secondary endpoints were a response to metronomic therapy, compliance, and toxicity. RESULTS: From June 2018 to May 2020, 25 patients were started on metronomic therapy. The median age was 60 years. The median overall survival was 8.8 months. At eight weeks of therapy, 11 patients (44%) had a partial response, ten patients had stable disease (40%), and four patients had progressive disease (16%). The compliance with the therapy was 100%, and one patient (4%) developed grade III toxicity. CONCLUSIONS: Considering the resource constraints and cost limitations in low and middle-income countries, oral metronomic therapy in the form of methotrexate and celecoxib should be regarded as a suitable regimen in the palliative treatment of patients with unresectable, metastatic, or advanced, recurrent cancers.

Estimation of Total Platelet Count From Peripheral Blood Smear Needs a Correction Factor.

Background Despite many advances in platelet counting by cell counters, the problem of falsely low or falsely high total platelet counts (TPC) is common. Many laboratories estimate platelet count on the peripheral smear to cross-check the platelet counts. However, due to the lack of a standard calculation method, discrepant results are obtained from different laboratories leading to confusion among clinicians. We aimed to formulate a standard estimation method for platelet count on peripheral smear. Methodology In the first step (in 100 blood samples), we determined the ratio of the TPC obtained by the automated cell counter and the total number of platelets per oil immersion field (filed size: 0.22 mm) of the corresponding blood smears. The mean of the ratios thus obtained was designated as the "multiplication factor" to be used for visual platelet count estimation on the peripheral blood smear. In the subsequent step, validation of the same was done on another 100 samples. TPC on the peripheral smears of these samples was estimated using the above "multiplication factor" and compared with the corresponding TPC obtained on the automated cell counter. Results The "multiplication factor" obtained was 9.4 x 103 in the first set of 100 blood samples. It was used to estimate the platelet value of the second set of 100 blood samples. Conclusions We found an excellent agreement between the platelet counts obtained by automated cell counters and the estimation method. We suggest the multiplication factor 9.4 x 103 may be used with correction for microscopic field size to estimate platelet count on peripheral smears. This method is, however, not so reliable for very low platelet counts.

Expression of mismatch repair proteins in urothelial carcinoma of the urinary bladder.

Background: Urothelial carcinoma of the urinary bladder (UCUB) is a frequently diagnosed malignancy. Mismatch repair (MMR), a proofreading machinery of the DNA, prevents tumorigenesis. The role of MMR deficiency in UCUB in eastern Indian population is not known. Methods: Immunohistochemistry panel for MLH1, PMS2, MSH2, and MSH6 (MMR proteins) was performed on the biopsy specimens of UCUB (N=100). Results: MMR deficiency by immunohistochemistry was demonstrated in two cases (2%). One case showed deficiency of MSH2 and MSH6 and the other case showed the deficiency of all four mismatch proteins. Both cases showed high-grade invasive urothelial carcinoma by histomorphology. Conclusion: The prevalence of MMR deficiency by immunohistochemistry is 2% in eastern Indian population.

Squamous Metaplasia in a Borderline Phyllodes Tumor-an Undocumented Histological Finding in Male Breast: Report of a Case and Review of Literature.

Phyllodes tumor is a paradigm of fibroepithelial neoplasm that accounts for <1% of the breast neoplastic lesions usually detected in females and uncommonly in the male breast. The World Health Organization classifies the tumor into benign, borderline, and malignant based on the predefined morphological criteria. Squamous differentiation in phyllodes tumor is epithelial metaplasia, which has been occasionally documented in English literature. We report the first undocumented case of a recurrent borderline phyllodes tumor with cystic squamous metaplastic change in a 32-year-old male patient. The histology was that of a fibroepithelial neoplasm with the typical leaf-like projections and cystic spaces lined by squamous epithelium containing keratin debris. The purpose of presenting this case is to elucidate the pathogenesis and discuss other malignant and benign breast lesions that may be included in the differential diagnosis when evaluating a breast lesion with squamous metaplasia, particularly in the context of fine-needle aspirates.

Diagnosis of the leukemic phase of ALK-positive anaplastic large cell lymphoma by immunohistochemistry on cell block prepared from peripheral blood buffy coat.

A leukemic phase of anaplastic lymphoma kinase positive anaplastic large cell lymphoma (ALK+ ALCL) is rare. The leukemic cells morphologically appear as small to intermediate-sized cells with cerebriform and cloverleaf-like nuclei and are misdiagnosed as other T-Cell lymphomas/leukemia with similar morphology. We describe a case where the diagnosis of leukemic ALK+ ALCL was aided by immunohistochemistry performed on the cell blocks prepared from the peripheral blood buffy coat specimen. The diagnosis of ALK+ ALCL was further confirmed on the biopsy of a cutaneous nodule of this patient. We found the method of immunohistochemistry on peripheral blood buffy coat cell block very useful and suggest that it may be used as an alternative method to flowcytometry in low resource settings.

NEDDylation negatively regulates ERRß expression to promote breast cancer tumorigenesis and progression.

Estrogen-related receptor beta (ERRß) is downregulated in breast cancer cells and its overexpression in breast cancer patients is positively correlated with an improved prognosis and prolonged relapse-free survival. Here, we unravelled a molecular mechanism for ERRß downregulation in breast cancer. We found that ERRß is a key substrate of the SCF complex and that NEDDylation can activate the Cullin subunits of the SCF complex to target ERRß for degradation in breast cancer. Consistently, using in vitro and in vivo models, we demonstrated that MLN4924, a specific small molecule inhibitor of NEDDylation, can restore ERRß expression and culminate in a reduction in cell proliferation and migration of breast cancer cells. We also showed that increased ERRß expression promotes the upregulation of its target genes, including the tumour suppressors p21Cip1/Waf1 and E-cadherin, involved in cell proliferation and migration arrest at the gene promoter level. Interestingly, this tumour suppressive role of ERRß does not depend on the expression of ERα in breast cancer. Moreover, our data revealed that the ERRß recruits the transcription co-activator p300 to its targeted gene promoters to upregulate their expression. Collectively, our work revealed that restoration of ERRß expression using the NEDDylation inhibitor MLN4924 can be a novel and effective strategy for breast cancer treatment.

Telangiectatic Squamous Cell Carcinoma of Uterine Cervix: A Previously Undescribed Variant of Squamous Cell Carcinoma.

Squamous cell carcinoma of the uterine cervix is the second most common malignancy in women worldwide. We describe an unusual telangiectatic variant of squamous cell carcinoma in a 53 yr old woman. The tumor showed the usual morphologic features of a poorly differentiated keratinizing squamous cell carcinoma with >75% tumor area showing cavernous hemangioma like ectatic spaces filled with blood. The blood-filled spaces lacked an endothelial lining as evidenced by negativity for CD31 and CD34. This unusual variant has not been reported previously. Awareness of this entity is necessary for avoiding confusion with vascular tumors such as hemangiomas and angiosarcoma.

Genome-wide expression analysis reveals six contravened targets of EZH2 associated with breast cancer patient survival.

Several pioneering work have established that apart from genetic alterations, epigenetic modifications contribute significantly in tumor progression. Remarkable role of EZH2 in cancer highlights the importance of identifying its targets. Although much emphasis has been placed in recent years in designing drugs and inhibitors targeting EZH2, less effort has been given in exploring its existing targets that will help in understanding the oncogenic role of EZH2 in turn which may provide a more stringent method of targeting EZH2. In the present study, we validated six direct targets of EZH2 that are GPNMB, PMEPA1, CoL5A1, VGLL4, POMT2 and SUMF1 associated with cancer related pathways. Upon EZH2 knockdown, more than two fold increase in the target gene expression was evident. CHIP-qPCR performed in both MCF-7 and MDA-MDA-231 confirmed the in-vivo binding of EZH2 on its identified target. Thirty invasive breast carcinoma cases with their adjacent normal tissues were included in the study. Immunohistochemistry in primary breast tumor tissue array showed tumor dependent expression of EZH2. Array of MERAV expression database revealed the strength of association of EZH2 with its target genes. Real time PCR performed with RNA extracted from breast tumor tissues further authenticated the existing negative correlation between EZH2 and its target genes. Pearson correlation coefficient & statistical significance computed using the matrix provided in the database strengthened the negative correlation between identified target genes and EZH2. KM plotter analysis showed improved relapse-free survival with increased expression of PMEPA1, POMT2, VGLL4 and SUMF1 in breast cancer patients indicating their therapeutic potential. While investigating the relevance of these target genes, different mutations of them were found in breast cancer patients. Seeking the clinical relevance of our study, following our recent publication that reports the role of EZH2 in nicotine-mediated breast cancer development and progression, we observed significant reduced expression of SUMF1 in breast cancer patient samples with smoking history in comparison to never-smoked patient samples.

Estrogen-related receptors alpha, beta and gamma expression and function is associated with transcriptional repressor EZH2 in breast carcinoma.

BACKGROUND: Orphan nuclear receptors ERRα, ERRß and ERRγ that belong to NR3B or type IV nuclear receptor family are well studied for their role in breast cancer pathophysiology. Their homology with the canonical estrogen receptor dictates their possible contributing role in mammary gland development and disease. Although function and regulation of ERRα, ERRγ and less about ERRß is reported, role of histone methylation in their altered expression in cancer cells is not studied. Transcriptional activity of nuclear receptors depends on co-regulatory proteins. The present study for the first time gives an insight into regulation of estrogen-related receptors by histone methylation specifically through methyltransferase EZH2 in breast cancer. METHODS: Expression of ERRα, ERRß, ERRγ and EZH2 was assessed by immunohistochemistry in four identical tissue array slides that were prepared as per the protocol. The array slides were stained with ERRα, ERRß, ERRγ and EZH2 simultaneously. Array data was correlated with expression in MERAV expression dataset. Pearson correlation coeficient r was calculated from the partial matrix expression values available at MERAV database to study the strength of association between EZH2 and three orphan nuclear receptors under study. By western blot and real time PCR, their correlated expression was studied in breast cancer cell lines MCF-7, MDA-MB-231, T47D and MDA-MB-453 including normal breast epithelial MCF-10A cells at both protein and RNA level. Regulation of ERRα, ERRß, ERRγ by EZH2 was further investigated upon overexpression and silencing of EZH2. The interaction between ERRs and EZH2 was validated in vivo by CHIP-qPCR. RESULTS: We found a negative correlation between estrogen-related receptors and Enhancer of Zeste Homolog 2, a global repressor gene. Immunohistochemistry in primary breast tumors of different grades showed a correlated expression of estrogen-related receptors and EZH2. Their correlated expression was further validated using online MERAV expression dataset where a negative correlation of variable strengths was observed in breast cancer. Ectopic expression of EZH2 in low EZH2-expressing normal breast epithelial cells abrogated their expression and at the same time, its silencing enhanced the expression of estrogen-related receptors in cancerous cells. Global occupancy of EZH2 on ERRα and ERRß was observed in-vivo. CONCLUSION: Our findings identify EZH2 as a relevant coregulator for estrogen-related receptors in breast carcinoma.

Juvenile granulosa cell tumor of the ovary presenting with pleural effusion and ascites.

Juvenile granulosa cell tumor (GCT) is a rare tumor, and the majority (90%) are reported in the prepubertal or under-30-year age group, in contrast to the adult type, which is more common in the fifth decade. On histopathological examination, juvenile GCTs are distinct from the adult type of GCT, and have a lower risk for late recurrences than the latter. Being solid tumors, they may be associated with ascites and pleural effusion (Meigs' syndrome), which resolve after surgical removal of the tumor. Tumor markers for GCT are still investigational (inhibin) and of not much use in making a preoperative diagnosis, unlike in the case of germ cell tumors. In most of the reports about the initial surgical management of GCT, retroperitoneal lymph node sampling was not performed, and it was not done in the patient we report here. However, lymph node sampling is advocated for complete staging of these tumors, as a significant number of recurrences are reported in the retroperitoneum, as well as in incompletely staged patients. In the present patient, because of the association of Meigs' syndrome, a preoperative diagnosis of benign tumors such as fibroma/thecoma was also considered. We report this rare tumor with an aim of reviewing the diagnosis and management from the reported literature.