Gigaxonin Suppresses Epithelial-to-Mesenchymal Transition of Human Cancer Through Downregulation of Snail.

Gigaxonin is an E3 ubiquitin ligase that plays a role in cytoskeletal stability. Its role in cancer is not yet clearly understood. Our previous studies of head and neck cancer had identified gigaxonin interacting with p16 for NFκB ubiquitination. To explore its role in cancer cell growth suppression, we analyzed normal and tumor DNA from cervical and head and neck cancers. There was a higher frequency of exon 8 SNP (c.1293 C>T, rs2608555) in the tumor (46% vs. 25% normal, P = 0.011) pointing to a relationship to cancer. Comparison of primary tumor with recurrence and metastasis did not reveal a statistical significance. Two cervical cancer cell lines, ME180 and HT3 harboring exon 8 SNP and showing T allele expression correlated with higher gigaxonin expression, reduced in vitro cell growth and enhanced cisplatin sensitivity in comparison with C allele expressing cancer cell lines. Loss of gigaxonin expression in ME180 cells through CRISPR-Cas9 or siRNA led to aggressive cancer cell growth including increased migration and Matrigel invasion. The in vitro cell growth phenotypes were reversed with re-expression of gigaxonin. Suppression of cell growth correlated with reduced Snail and increased e-cadherin expression. Mouse tail vein injection studies showed increased lung metastasis of cells with low gigaxonin expression and reduced metastasis with reexpression of gigaxonin. We have found an association between C allele expression and RNA instability and absence of multimeric protein formation. From our results, we conclude that gigaxonin expression is associated with suppression of epithelial-mesenchymal transition through inhibition of Snail. SIGNIFICANCE: Our results suggest that GAN gene exon 8 SNP T allele expression correlates with higher gigaxonin expression and suppression of aggressive cancer cell growth. There is downregulation of Snail and upregulation of e-cadherin through NFκB ubiquitination. We hypothesize that exon 8 T allele and gigaxonin expression could serve as diagnostic markers of suppression of aggressive growth of head and neck cancer.

A phase I study of Mirvetuximab Soravtansine and gemcitabine in patients with FRα-positive recurrent ovarian, primary peritoneal, fallopian tube, or endometrial cancer, or triple negative breast cancer.

OBJECTIVE: Platinum-resistant epithelial ovarian cancer (EOC), recurrent endometrial cancer (EC), and triple negative breast cancer (TNBC) are difficult to treat after failing standard therapies. This phase I study evaluated mirvetuximab soravtansine (MIRV) and gemcitabine in patients with recurrent FRα-positive EOC, EC, or TNBC to determine the maximum tolerated dose (MTD)/recommended phase 2 dose (RP2D) (primary endpoint). METHODS: FRα-positive patients with platinum-resistant EOC, EC, or TNBC with ≤4 prior chemotherapy regimens (2 for EC) were enrolled. FRα expression requirement varied among eligible tumors and changed during the study. RESULTS: Twenty patients were enrolled; 17 were evaluable for DLT. Half the patients received ≥3 prior chemotherapy lines. Most EOC and EC patients (78%) were medium (50-74%) or high(75-100%) FRα expressors. TNBC patients were low (25-49%) FRα expressors. The MTD/RP2D was MIRV 6 mg/kg AIBW D1 and gemcitabine 800 mg/m2 IV, D1 and D8, every 21 days (Dose Level [DL] 3), where 5/7 patients demonstrated a partial response (PR) as their best response, including 2 confirmed ovarian responses whose time-to-progression and duration of response were 7.9/5.4 and 8.0/5.7 months respectively. Most common treatment-related adverse events at MTD were anemia and neutropenia (3/7 each, 43%), diarrhea, hypophosphatemia, thrombocytopenia, and leukopenia (2/7 each, 29%). DLTs were thrombocytopenia (DL1), oral mucositis (DL4) and diarrhea (DL4). Nine of 20 patients (45%; 95% CI: 21.1-68.9%) achieved PR as their best response, with 3/20 patients or 15% (95%CI, 0-32.1%) confirmed PR. CONCLUSION: MIRV and gemcitabine demonstrate promising activity in platinum resistant EOC at RP2D, but frequent hematologic toxicities.

HPV genotyping by L1 amplicon sequencing of archived invasive cervical cancer samples: a pilot study.

BACKGROUND: Human papillomavirus (HPV) is the primary cause of invasive cervical cancer (ICC). The prevalence of various HPV genotypes, ranging from oncogenically low- to high-risk, may be influenced by geographic and demographic factors, which could have critical implications for the screening and prevention of HPV infection and ICC incidence. However, many technical factors may influence the identification of high-risk genotypes associated with ICC in different populations. METHODS: We used high-throughput sequencing of a single amplicon within the HPV L1 gene to assess the influence of patient age, race/ethnicity, histological subtype, sample type, collection date, experimental factors, and computational parameters on the prevalence of HPV genotypes detected in archived DNA (n = 34), frozen tissue (n = 44), and formalin-fixed paraffin-embedded (FFPE) tissue (n = 57) samples collected in the Los Angeles metropolitan area. RESULTS: We found that the percentage of off-target human reads and the concentration of DNA amplified from each sample varied by HPV genotype and by archive type. After accounting for the percentage of human reads and excluding samples with especially low levels of amplified DNA, the HPV prevalence was 95% across all ICC samples: HPV16 was the most common genotype (in 56% of all ICC samples), followed by HPV18 (in 21%). Depending upon the genotyping parameters, the prevalence of HPV58 varied up to twofold in our cohort. In archived DNA and frozen tissue samples, we detected previously established differences in HPV16 and HPV18 frequencies based on histological subtype, but we could not reproduce those findings using our FFPE samples. CONCLUSIONS: In this pilot study, we demonstrate that sample collection, preparation, and analysis methods can influence the detection of certain HPV genotypes and must be carefully considered when drawing any biological conclusions based on HPV genotyping data from ICC samples.

First Case of Invasive Stachybotrys Sinusitis.

BACKGROUND: The toxigenic mold Stachybotrys has controversially been linked to idiopathic pulmonary hemorrhage and "sick building syndrome." However, there are no previous clinical records of invasive stachybotryosis. METHODS: Sinus biopsy specimens from a 23-year-old male with refractory acute lymphocytic leukemia were obtained at 3 different time points during the patient's hospitalization (139 days) and examined by histopathology and immunohistochemistry (IHC). Antifungal susceptibility testing and fungal speciation using multilocus sequence typing were performed. RESULTS: Hemorrhage, fungal germination, and hyphal growth were observed in the first sinus biopsy tissues. Areas with fungal growth tested positive for Stachybotrys by IHC. Fungal isolates were genotyped and identified as Stachybotrys chlorohalonata. The patient was cured from Stachybotrys sinusitis following sinus surgery and antifungal treatment. While a subsequent second sinus biopsy and a bronchoscopy showed no signs of fungal infection, a later, third sinus biopsy tested positive for Aspergillus calidoustus, a rare human pathogen. CONCLUSIONS: Here, we report the first case of invasive S. chlorohalonata sinusitis that was surgically and medically cured but followed by invasive A. calidoustus sinusitis in the setting of refractory leukemia. Our findings emphasize the risk for unusual fungal infections in severely immunocompromised patients.

Dysregulation of hsa-miR-34a and hsa-miR-449a leads to overexpression of PACS-1 and loss of DNA damage response (DDR) in cervical cancer.

We have observed overexpression of PACS-1, a cytosolic sorting protein in primary cervical tumors. Absence of exonic mutations and overexpression at the RNA level suggested a transcriptional and/or posttranscriptional regulation. University of California Santa Cruz genome browser analysis of PACS-1 micro RNAs (miR), revealed two 8-base target sequences at the 3' terminus for hsa-miR-34a and hsa-miR-449a. Quantitative RT-PCR and Northern blotting studies showed reduced or loss of expression of the two microRNAs in cervical cancer cell lines and primary tumors, indicating dysregulation of these two microRNAs in cervical cancer. Loss of PACS-1 with siRNA or exogenous expression of hsa-miR-34a or hsa-miR-449a in HeLa and SiHa cervical cancer cell lines resulted in DNA damage response, S-phase cell cycle arrest, and reduction in cell growth. Furthermore, the siRNA studies showed that loss of PACS-1 expression was accompanied by increased nuclear γH2AX expression, Lys382-p53 acetylation, and genomic instability. PACS-1 re-expression through LNA-hsa-anti-miR-34a or -449a or through PACS-1 cDNA transfection led to the reversal of DNA damage response and restoration of cell growth. Release of cells post 24-h serum starvation showed PACS-1 nuclear localization at G1-S phase of the cell cycle. Our results therefore indicate that the loss of hsa-miR-34a and hsa-miR-449a expression in cervical cancer leads to overexpression of PACS-1 and suppression of DNA damage response, resulting in the development of chemo-resistant tumors.

Frontline Management of Epithelial Ovarian Cancer-Combining Clinical Expertise with Community Practice Collaboration and Cutting-Edge Research.

Epithelial ovarian cancer (EOC) is the most common histology of ovarian cancer defined as epithelial cancer derived from the ovaries, fallopian tubes, or primary peritoneum. It is the fifth most common cause of cancer-related death in women in the United States. Because of a lack of effective screening and non-specific symptoms, EOC is typically diagnosed at an advanced stage (FIGO stage III or IV) and approximately one third of patients have malignant ascites at initial presentation. The treatment of ovarian cancer consists of a combination of cytoreductive surgery and systemic chemotherapy. Despite the advances with new cytotoxic and targeted therapies, the five-year survival rate for all-stage EOC in the United States is 48.6%. Delivery of up-to-date guideline care and multidisciplinary team efforts are important drivers of overall survival. In this paper, we review our frontline management of EOC that relies on a multi-disciplinary approach drawing on clinical expertise and collaboration combined with community practice and cutting edge clinical and translational research. By optimizing partnerships through team medicine and clinical research, we combine our cancer center clinical expertise, community practice partnership, and clinical and translational research to understand the biology of this deadly disease, advance therapy and connect our patients with the optimal treatment that offers the best possible outcomes.

Molecular subtypes of triple-negative breast cancer in women of different race and ethnicity.

Molecular subtypes of triple negative breast cancer (TNBC) are associated with variation in survival and may assist in treatment selection. However, the association of patient race or ethnicity with subtypes of TNBC and clinical outcome has not been addressed. Using nCounter Gene Expression Codesets, we classified TNBCs into subtypes: basal-like immune-activated (BLIA), basal-like immunosuppressed (BLIS), luminal androgen receptor (LAR), and mesenchymal (MES) in 48 Hispanic, 12 African-American, 21 Asian, and 34 White patients. Mean age at diagnosis was significantly associated with subtype, with the youngest mean age (50 years) in MES and the oldest mean age (64 years) in LAR (p < 0.0005). Subtype was significantly associated with tumor grade (p = 0.0012) and positive lymph nodes (p = 0.021), with a marginally significant association of tumor stage (p = 0.076). In multivariate Cox-proportional hazards modeling, BLIS was associated with worst survival and LAR with best survival. Hispanics had a significantly higher proportion of BLIS (53%, p = 0.03), whereas Asians had a lower proportion of BLIS (19%, p = 0.05) and a higher proportion of LAR (38%, p = 0.06) compared to the average proportion across all groups. These differences in proportions of subtype across racial and ethnic groups may explain differences in their outcomes. Determining subtypes of TNBC facilitates understanding of the heterogeneity of the TNBCs and provides a foundation for developing subtype-specific therapies and better predictors of TNBC prognosis for all races and ethnicities.

p53-Reactive T Cells Are Associated with Clinical Benefit in Patients with Platinum-Resistant Epithelial Ovarian Cancer After Treatment with a p53 Vaccine and Gemcitabine Chemotherapy.

Purpose: To conduct a phase I trial of a Modified Vaccinia Ankara vaccine delivering wild-type human p53 (p53MVA) in combination with gemcitabine chemotherapy in patients with platinum-resistant ovarian cancer.Experimental Design: Patients received gemcitabine on days 1 and 8 and p53MVA vaccine on day 15, during the first 3 cycles of chemotherapy. Toxicity was classified using the NCI Common Toxicity Criteria and clinical response assessed by CT scan. Peripheral blood samples were collected for immunophenotyping and monitoring of anti-p53 immune responses.Results: Eleven patients were evaluated for p53MVA/gemcitabine toxicity, clinical outcome, and immunologic response. TOXICITY: there were no DLTs, but 3 of 11 patients came off study early due to gemcitabine-attributed adverse events (AE). Minimal AEs were attributed to p53MVA vaccination. Immunologic and clinical response: enhanced in vitro recognition of p53 peptides was detectable after immunization in both the CD4+ and CD8+ T-cell compartments in 5 of 11 and 6 of 11 patients, respectively. Changes in peripheral T regulatory cells (Tregs) and myeloid-derived suppressor cells (MDSC) did not correlate significantly with vaccine response or progression-free survival (PFS). Patients with the greatest expansion of p53-reactive T cells had significantly longer PFS than patients with lower p53-reactivity after therapy. Tumor shrinkage or disease stabilization occurred in 4 patients.Conclusions: p53MVA was well tolerated, but gemcitabine without steroid pretreatment was intolerable in some patients. However, elevated p53-reactive CD4+ and CD8+ T-cell responses after therapy correlated with longer PFS. Therefore, if responses to p53MVA can be enhanced with alternative agents, superior clinical responses may be achievable. Clin Cancer Res; 24(6); 1315-25. ©2018 AACR.

Randomized trial of medroxyprogesterone acetate for the prevention of endometrial pathology from adjuvant tamoxifen for breast cancer: SWOG S9630.

The proliferative effect of adjuvant tamoxifen on the endometrium can potentially result in endometrial abnormalities, including cancer in postmenopausal women. We conducted a randomized, controlled trial to assess endometrial pathological diagnoses in postmenopausal women with early stage, ER-positive breast cancer without endometrial pathology at baseline. They were assigned to tamoxifen alone versus tamoxifen plus cyclical medroxyprogesterone acetate (MPA 10 mg for 14 days every 3 months) for 5 years. Endovaginal sonograms (EVS) +/- endometrial biopsies (EMB) were required at baseline, 2 and 5 years. Of 313 patients registered, 296 were eligible and 169 (57%; 89, tamoxifen; 80, tamoxifen+MPA) were evaluable (completed year-2 EVS, with an EMB if stripe width was ⩾5 mm). Sixty (67%) of these in the tamoxifen arm had an endometrial stripe width ⩾5 mm (and underwent subsequent EMB) compared with 48 (60%) in the tamoxifen+MPA arm (P=0.40). There were four cases of proliferative endometrium and one simple hyperplasia on the tamoxifen arm (6% (95% confidence interval (CI): 2-13%) among evaluable patients and one proliferative endometrium on the tamoxifen+MPA arm (P=0.11). The overall fraction with benign endometrial abnormalities at year 2 was 3.6% (6/169; 95% CI: 1.3-7.6%), with only 1 (of 102) new benign proliferative event at year 5. The event rate in both arms was much lower than projected, making treatment arm comparisons less informative. A normal endometrium prior to tamoxifen may provide reassurance regarding future endometrial events. However, validation in a larger trial is needed before changing practice in asymptomatic, postmenopausal women.

Human breast cancer metastases to the brain display GABAergic properties in the neural niche.

Dispersion of tumors throughout the body is a neoplastic process responsible for the vast majority of deaths from cancer. Despite disseminating to distant organs as malignant scouts, most tumor cells fail to remain viable after their arrival. The physiologic microenvironment of the brain must become a tumor-favorable microenvironment for successful metastatic colonization by circulating breast cancer cells. Bidirectional interplay of breast cancer cells and native brain cells in metastasis is poorly understood and rarely studied. We had the rare opportunity to investigate uncommonly available specimens of matched fresh breast-to-brain metastases tissue and derived cells from patients undergoing neurosurgical resection. We hypothesized that, to metastasize, breast cancers may escape their normative genetic constraints by accommodating and coinhabiting the neural niche. This acquisition or expression of brain-like properties by breast cancer cells could be a malignant adaptation required for brain colonization. Indeed, we found breast-to-brain metastatic tissue and cells displayed a GABAergic phenotype similar to that of neuronal cells. The GABAA receptor, GABA transporter, GABA transaminase, parvalbumin, and reelin were all highly expressed in breast cancer metastases to the brain. Proliferative advantage was conferred by the ability of breast-to-brain metastases to take up and catabolize GABA into succinate with the resultant formation of NADH as a biosynthetic source through the GABA shunt. The results suggest that breast cancers exhibit neural characteristics when occupying the brain microenvironment and co-opt GABA as an oncometabolite.

Merkel cell carcinoma of lymph node with unknown primary has a significantly lower association with Merkel cell polyomavirus than its cutaneous counterpart.

Rare cases of Merkel cell carcinoma have been encountered in lymph nodes with unknown extranodal primary, which exhibit similar morphologic and immunophenotypic features to those in primary cutaneous Merkel cell carcinomas. However, it is uncertain whether the nodal Merkel cell carcinoma is a primary tumor of the lymph node or represents a metastasis from an occult or regressed extranodal lesion. To establish an accurate diagnosis of the nodal Merkel cell carcinoma can be challenging because of significant morphologic mimics, including lymphoblastic lymphoma and metastatic small cell carcinoma. Moreover, there is no consensus for a diagnostic term, and many different terms have been used, which can be confusing and may not fully reflect the nature of nodal Merkel cell carcinoma. In this study, we investigated the detailed clinicopathologic features of 22 nodal Merkel cell carcinomas, with comparison to 763 primary cutaneous cases retrieved from the literature. Overall, the nodal and cutaneous Merkel cell carcinomas shared similar clinical presentations, morphologic spectrum, and immunophenotype; both were mostly seen in elderly male with a typical neuroendocrine morphology. Most of cases expressed CK20, synaptophysin, and chromogranin A; and PAX5 and TdT were also positive in majority of cases. However, nodal Merkel cell carcinomas had a significantly lower association with Merkel cell polyomavirus than cutaneous cases (31% vs 76%, P=0.001). Therefore, these two entities may arise from overlapping but not identical biological pathways. We also recommend the use of the diagnostic term 'Merkel cell carcinoma of lymph node' to replace many other names used.

Identification of a 4-microRNA signature for clear cell renal cell carcinoma metastasis and prognosis.

Renal cell carcinoma (RCC) metastasis portends a poor prognosis and cannot be reliably predicted. Early determination of the metastatic potential of RCC may help guide proper treatment. We analyzed microRNA (miRNA) expression in clear cell RCC (ccRCC) for the purpose of developing a miRNA expression signature to determine the risk of metastasis and prognosis. We used the microarray technology to profile miRNA expression of 78 benign kidney and ccRCC samples. Using 28 localized and metastatic ccRCC specimens as the training cohort and the univariate logistic regression and risk score methods, we developed a miRNA signature model in which the expression levels of miR-10b, miR-139-5p, miR-130b and miR-199b-5p were used to determine the status of ccRCC metastasis. We validated the signature in an independent 40-sample testing cohort of different stages of primary ccRCCs using the microarray data. Within the testing cohort patients who had at least 5 years follow-up if no metastasis developed, the signature showed a high sensitivity and specificity. The risk status was proven to be associated with the cancer-specific survival. Using the most stably expressed miRNA among benign and tumorous kidney tissue as the internal reference for normalization, we successfully converted his signature to be a quantitative PCR (qPCR)-based assay, which showed the same high sensitivity and specificity. The 4-miRNA is associated with ccRCC metastasis and prognosis. The signature is ready for and will benefit from further large clinical cohort validation and has the potential for clinical application.

Laminin 332 expression in breast carcinoma.

Laminin 332 (LN332) is a basally expressed extracellular matrix protein that enhances the migration and invasion of breast carcinoma cells. The goal of this study was to examine LN332 expression breast carcinoma. Triple negative breast carcinomas lack estrogen receptor (ER), progesterone receptor (PR) expression and HER2 positivity. Immunohistochemistry for ER, PR, HER2, and dual silver in situ hybridization for the HER2 gene were used to define the phenotype of 243 breast cancers in biopsies or arrays. Immunohistochemistry for LN332 revealed that 70% of triple negative carcinomas stained for LN332. Cytokeratins 5/6 (CK5/6), epidermal growth factor receptor and p63 alone stained fewer triple negative breast carcinomas each, but the combination of LN332 and CK5/6 or epidermal growth factor receptor identified 92% of triple negative breast carcinoma. Of the 163 non-triple negative cases, LN332 was expressed in only 15%. The identification of LN332 in triple negative breast carcinomas is consistent with gene profiling studies showing its expression among breast carcinomas with a basal phenotype. The observation that a proinvasive protein such as LN332 is expressed in breast cancer suggests another mechanism by which the triple negative phenotype could be aggressive.

Prospective evaluation of an in vitro radiation resistance assay in locally advanced cancer of the uterine cervix: a Southwest Oncology Group Study.

OBJECTIVES: To investigate the feasibility of performing a fresh-tissue, in vitro radiation resistance assay (IVRRA) in a cooperative group setting and to assess the association of IVRRA results with clinical outcomes. METHODS: Women with Stages IIB-IVA carcinoma of the uterine cervix without obvious para-aortic lymphadenopathy on imaging were eligible. Primary tumor biopsies were shipped to a central testing facility where agar-based cell suspensions were exposed to 300 cGy of RT ± cisplatin and cultured for 5 days. ³H-thymidine incorporation was used to determine percent cell inhibition (PCI) of test specimen compared to that of the untreated control. Tumors were considered to exhibit extreme radiation resistance (ERR), intermediate radiation resistance (IRR) or low radiation resistance (LRR) based on a standard data set from 39 previously studied specimens. Standardized doses of external beam radiation and intracavitary brachytherapy, when feasible, in addition to platinum-based chemotherapy were mandated. Progression-free survival (PFS) was the primary endpoint. Clinical response and overall survival (OS) were secondary endpoints. Clinical investigators were blinded to assay data and vice versa. RESULTS: Thirty-six patients were enrolled, but analysis was limited to 17 patients whose specimens were adequate for IVRRA. The median follow-up time among patients still alive at last contact was 40 months (range: 0-56 months). There was no association between IVRRA and response. In the Cox model, IRR/ERR tumors showed worse PFS [HR = 11.2 (95% CI 1.3-96, p = 0.03)] and worse OS [HR=11.7 (95% CI 1.4-99.6, p = 0.03)] compared to LRR tumors when IVRRA was performed with RT alone, but there were no associations between IVRRA and PFS or OS when cisplatin was added to the IVRRA. CONCLUSIONS: IVRRA (RT alone) results correlated with PFS and OS in this prospective trial, but follow-up trials are indicated to address feasibility and to confirm results in an expanded cohort. If confirmed, IVRRA could potentially direct molecular identification of novel targeted therapeutic approaches which might counteract radiation resistance.

Single agent carboplatin versus carboplatin plus pegylated liposomal doxorubicin in recurrent ovarian cancer: final survival results of a SWOG (S0200) phase 3 randomized trial.

OBJECTIVES: Randomized phase 3 trials have demonstrated the utility of a regimen of carboplatin plus pegylated liposomal doxorubicin (PLD) in recurrent ovarian cancer, and have provided provocative data suggesting a substantially lower risk of carboplatin-associated hypersensitivity if PDL is delivered in combination with the platinum agent. METHODS: To further examine both of these clinically-relevant issues, the survival outcome (with longer follow-up) and hypersensitivity reaction profile of a previously reported phase 3 trial that compared single agent carboplatin (AUC 5) to carboplatin (AUC 5) plus PLD (30 mg/m(2)) delivered on an every 4-week schedule in recurrent ovarian cancer (SWOG 0200) were re-analyzed. RESULTS: In the limited number of patients (n=61) entered into this phase 3 study before closure by the SWOG Data Safety and Monitoring Committee due to insufficient accrual, there was an initially reported improvement in outcome associated with the combination regimen. With longer follow-up and additional events there is still a statistically-significant improved progression-free survival (median: 12 versus 8 months, p=0.02), but the previously observed impact of the two-drug regimen on overall survival is no longer apparent (median: 31 versus 18 months; p=0.2). While no hypersensitivity reactions were reported in the carboplatin plus PLD arm (0/31), 9 of 30 patients (30%) of women randomized to single agent carboplatin experienced an allergic episode (p=0.0008), with 5 being >grade 2 in severity. CONCLUSION: Despite a favorable impact of carboplatin and PLD on progression-free survival in this trial, the effect on overall survival is not statistically significant. For currently unknown reasons, administering PLD with carboplatin appears to substantially reduce the incidence of platinum-associated hypersensitivity reactions.