Nicole A. Massoll

A novel small molecule inhibitor of FAK decreases growth of human pancreatic cancer

Focal adhesion kinase (FAK) is a cytoplasmic tyrosine kinase that is overexpressed in many types of tumors, including pancreatic cancer, and plays an important role in cell adhesion and survival signaling. Pancreatic cancer is a lethal disease and is very resistant to chemotherapy, and FAK has been shown recently to assist in tumor cell survival. Therefore, FAK is an excellent potential target for anti-cancer therapy. We identified a novel small molecule inhibitor (1,2,4,5-Benzenetetraamine tetrahydrochloride, that we called Y15) targeting the main autophosphorylation site of FAK and hypothesized that it would be an effective treatment strategy against human pancreatic cancer. Y15 specifically blocked phosphorylation of Y397-FAK and total phosphorylation of FAK. It directly inhibited FAK autophosphorylation in a dose- and time-dependent manner. Furthermore, Y15 increased pancreatic cancer cell detachment and inhibited cell adhesion in a dose-dependent manner. Y15 effectively caused human pancreatic tumor regression in vivo, when administered alone and its effects were synergistic with gemcitabine chemotherapy. This was accompanied by a decrease in Y397-phosphorylation of FAK in the tumors treated with Y15. Thus, targeting the Y397 site of FAK in pancreatic cancer with the small molecule inhibitor, 1,2,4,5-Benzenetetraamine tetrahydrochloride, is a potentially effective treatment strategy in this deadly disease.

The role of Yersinia enterocolitica and Yersinia pseudotuberculosis in granulomatous appendicitis: A histologic and molecular study

Granulomatous appendicitis is an enigmatic entity. Purported causes include Crohns disease, foreign body reactions, sarcoidosis, and infectious agents; however, most cases remain idiopathic. Yersinia enterocolitica (YE) and Y. pseudotuberculosis (YP) have been implicated as causes of appendicitis, ileocolitis, and mesenteric adenitis. The authors examined the potential role of YE and YP in granulomatous appendicitis using histologic and molecular methods. Forty cases of granulomatous appendicitis were evaluated for histologic features including transmural inflammation, number and character of granulomas, and mucosal changes. Twort Gram, Grocott methenamine-silver (GMS), and Ziehl–Neelsen stains were evaluated, and polymerase chain reaction (PCR) analysis was performed to identify pathogenic YP and YE. Twenty-five percent (10 of 40) of the cases were positive for pathogenic Yersinia by PCR (four YE, four YP, and two with both species). Prominent histologic features included epithelioid granulomas with lymphoid cuffing, transmural inflammation with lymphoid aggregates, mucosal ulceration, and cryptitis. One Yersinia-positive case contained mural Gram-negative bacilli; fungal and acid-fast bacilli stains were all negative. Except for one culture-negative case, serologies and cultures were not done or results were unavailable. Two Yersinia-positive patients were diagnosed subsequently with Crohns disease, suggesting a possible relationship between the two entities. No other patients developed significant sequelae. YE and YP are important causes of granulomatous appendicitis, and Yersinia infection may mimic Crohns disease. No histologic features distinguish reliably between Yersinia species, or between Yersinia-positive and Yersinia-negative cases. Because special stains and cultures are often not diagnostic, PCR analysis is an excellent technique for the diagnosis of Yersinia.

Molecular and Morphologic Distinctions between Infiltrating Ductal and Lobular Carcinoma of the Breast

Abstract:  Histopathologic distinction between ductal and lobular carcinomas of the breast has been made since 1941. Together, these two subtypes account for >95% of all mammary carcinomas. With the recent advances in molecular techniques, our understanding of the biology behind these carcinomas has greatly expanded. The genomic aberrations in mammary carcinoma are highly complex and appear to be more associated with tumor grade rather than any histopathologic subtype. Protein and RNA expression profiling reveals a classification of mammary carcinoma that has some overlap with traditional histopathology and can at least partially explain clinical behavior. The goal of this review is to present what is currently known about the molecular profiles of infiltrating ductal and lobular carcinoma and how they relate to conventional histopathology and biologic behavior.

p53 regulates FAK expression in human tumor cells.

Attenuation of the p53 protein is one of the most common abnormalities in human tumors. Another important marker of tumorigenesis is focal adhesion kinase (FAK), a 125‐kDa tyrosine kinase that is overexpressed at the mRNA and protein levels in a variety of human tumors. FAK is a critical regulator of adhesion, motility, metastasis, and survival signaling. We have characterized the FAK promoter and demonstrated that p53 can inhibit the FAK promoter activity in vitro. In the present study, we showed that p53 can bind the FAK promoter‐chromatin region in vivo by chromatin immunoprecipitation (ChIP) assay. Furthermore, we demonstrated down‐regulation of FAK mRNA and protein levels by adenoviral overexpression of p53. We introduced plasmids with different mutations in the DNA‐binding domain of p53 (R175H, p53 R248W and R273H) into HCTp53−/− cells and showed that these mutations of p53 did not bind FAK promoter and did not inhibit FAK promoter activity, unlike wild type p53. We analyzed primary breast and colon cancers for p53 mutations and FAK expression, and showed that FAK expression was increased in tumors containing mutations of p53 compared to tumors with wild type p53. In addition, tumor‐derived missense mutations in the DNA‐binding domain (R282, R249, and V173) also led to increased FAK promoter activity. Thus, the present data show that p53 can regulate FAK expression during tumorigenesis.

Human Papillomavirus Infection and p16ink4a Protein Expression in Vulvar Intraepithelial Neoplasia and Invasive Squamous Cell Carcinoma

Objective. Vulvar intraepithelial neoplasia (VIN) is defined histopathologically by distinctive abnormalities of cellular maturation and differentiation. The purpose of this study was to investigate the functional properties of VIN related to expression of p16INK4a protein as well as to detection of human papillomavirus (HPV) type 16 by real-time polymerase chain reaction (RT-PCR) analysis. Methods. A total of 49 vulvar biopsy samples were examined by hematoxylin-eosin staining from benign/reactive lesions, condyloma acuminatum, VIN, and invasive squamous cell carcinoma (SCC). JC8 mouse monoclonal antibodies were used that recognize p16INK4a epitope at a dilution of 1:25. The reaction pattern for p16INK4a was graded in each sample between 0 and 3+. RT-PCR analysis of formalin-fixed paraffin-embedded sections determined positivity for HPV type 16. Results. p16INK4a immunoreactivity was different in VIN 1, VIN 2, VIN 3, and squamous cell carcinoma. Strong expression of p16INK4a protein was observed in 92% (22 of 24) of VIN 2 and VIN 3 lesions and 100% (4 of 4) of invasive SCCs. Two (67%) of 3 VIN 2 lesions, 17 (81%) of 21 VIN 3 lesions, and 4 (100%) of 4 SCCs were positive for HPV type 16 by PCR analysis. Two (20%) of 10 VIN 1 lesions were immunoreactive for p16INK4a, with only 1 lesion positive for HPV type 16. No p16INK4a immunoreactivity was observed in any of the benign/reactive and condyloma acuminatum lesions. In addition, none of the benign/reactive or condyloma lesions were positive for HPV type 16 by RT-PCR analysis. Conclusions. Upregulation of INK4a gene occurs in vulvar carcinogenesis. p16INK4a is not a sensitive marker for differentiation of benign vulvar squamous epithelium from condyloma acuminatum or VIN 1 lesions because most VIN 1 lesions are p16INK4a negative. Expression of p16INK4a may aid in the diagnosis of HPV-related lesions and as such may be of value as a surrogate marker in the diagnosis of vulvar premalignant and malignant lesions.

Uterine-like Mass With Features of an Extrauterine Adenomyoma Presenting 22 Years After Total Abdominal Hysterectomy–Bilateral Salpingo-oophorectomy: A Case Report and Review of the Literature

Adenomyoma is a benign tumor composed of smooth muscle and benign endometrium. These tumors typically originate within the uterus. An extrauterine adenomyoma is a rare entity. We report a uterine-like mass consistent with an extrauterine adenomyoma presenting 22 years following a total abdominal hysterectomy and bilateral salpingo-oophorectomy. The mass was pear-shaped with uterine-type smooth muscle and a cavity lined by functional endometrial glands and stroma. To our knowledge, only 4 other cases of an extrauterine uterine-like mass are reported in the literature. Three involved the ovary, while one was located adjacent to the broad ligament with normal pelvic organs. Although none of these other uterus-like masses were described as adenomyomas with uterine-like features, the histologic findings are strikingly similar. An understanding of the müllerian system suggests that either an embryologic malformation or a differential multipotentiality existing in the subcoelomic tissues in response to hormonal stimulation results in a supernumerary müllerian structure like a uterus, as observed in this case. The presence of endometrial glands and stroma in the mass confirms that the tissues in this mass are hormonally responsive. It is most likely that this uterine-like mass arose from the tissues of the secondary müllerian system in response to estrogenic stimulation.

The Utility of p16 Ink4a in Discriminating Between Cervical Intraepithelial Neoplasia 1 and Nonneoplastic Equivocal Lesions of the Cervix

CONTEXT The protein p16(Ink4a) is overexpressed in cervical lesions associated with high-risk human papillomavirus (HPV) subtypes 16 and 18, but not in low-risk HPV subtypes 6 and 11 or non-HPV-associated cervical lesions. OBJECTIVE To determine whether p16(Ink4a) expression in equivocal cervical lesions helps distinguish atypical non-HPV changes from HPV-related changes. DESIGN One hundred ninety-one cervical lesions, including 81 cervical intraepithelial neoplasia 1, 52 squamous metaplasia, 33 cellular features suggestive of HPV-related change, 9 reserve cell hyperplasia, 4 microglandular hyperplasia, and 12 inflammatory cervicitis, were randomly selected from archival cervical biopsy specimens. All 191 samples were studied with p16(Ink4a) (JC8 monoclonal antibody). Reactivity for p16(Ink4a) was scored on a 3-tier system as follows: negative, 0% to 5% cells reactive; focal/scattered positive, greater than 5% and less than or equal to 80% cells reactive; diffuse positive, greater than 80% cells reactive. Reactivity was based on normal/reactive cervical specimens where anti-p16 antibody was negative/weakly expressed in non-cervical epithelial cells. Cervical intraepithelial neoplasia 1 lesions not reactive for p16(Ink4a) were investigated for the presence of high-risk HPV by real-time polymerase chain reaction. RESULTS No p16(Ink4a) reactivity was detected in the cervical lesions associated with atypical non-HPV change. Eleven of the cervical intraepithelial neoplasia 1 lesions showed focal/scattered reactivity expression for p16(Ink4a), and 19 of the CIN 1 lesions had diffuse reactivity. Fifty of 51 of the CIN 1 lesions negative for p16(Ink4a) were real-time polymerase chain reaction negative for the presence of high-risk HPV; 1 was real-time polymerase chain reaction positive for high-risk HPV. CONCLUSIONS The data support the routine use of p16(Ink4a) immunohistochemical evaluation of cervical biopsy specimens for better discrimination of non-HPV-associated lesions from HPV-related lesions.

A novel strategy to inhibit FAK and IGF-1R decreases growth of pancreatic cancer xenografts.

Deregulation of insulin‐like growth factor‐1 receptor (IGF‐1R) and focal adhesion kinase (FAK) signaling pathways plays an important role in cancer cell proliferation and metastasis. In pancreatic cancer cells, the crosstalk and compensatory mechanisms between these two pathways reduce the efficacy of the treatments that target only one of the pathways. Ablation of IGF‐1R signaling by siRNA showed minimal effects on the survival and growth of pancreatic cancer cells. An increased activity of FAK pathway was seen in these cells after IGF‐1R knockdown. Further inhibition of FAK pathway using Y15 significantly decreased cell survival, adhesion, and promoted apoptosis. The combination of Y15 treatment and IGF‐1R knockdown also showed significant antitumor effect in vivo. The current study demonstrates the importance of dual inhibition of both these signaling pathways as a novel strategy to decrease both in vitro and in vivo growth of human pancreatic cancer.

Focal Adhesion Kinase Expression in Human Neuroblastoma: Immunohistochemical and Real-time PCR Analyses

Purpose: The focal adhesion kinase (FAK) is a nonreceptor protein tyrosine kinase important in signaling between cells and their extracellular matrix. Studies have shown that FAK expression is up-regulated in several human tumors and is related to tumor progression. We recently found an increase in p125FAK expression in human neuroblastoma cells lines and wished to determine its expression in human neuroblastoma specimens and evaluate for a possible correlation between p125FAK expression and known prognostic factors for neuroblastoma. We hypothesized that p125FAK expression would be up-regulated in advanced human neuroblastomas. Experimental Design: Using immunohistochemical techniques with monoclonal antibody 4.47 specific for p125FAK expression, we analyzed 70 formalin-fixed, paraffin-embedded human neuroblastoma specimens for p125FAK staining. In addition, real-time PCR was used to determine the abundance of FAK mRNA in 17 matched human neuroblastoma mRNA specimens. Results: FAK staining was present in 51 of the 70 tumor specimens (73%). Immunohistochemical staining of p125FAK in the ganglion-type tumor cells correlated with advanced International Neuroblastoma Staging System tumor stages and FAK mRNA abundance. In addition, p125FAK staining was significantly increased in stage IV tumors with amplification of the N-MYC oncogene. Conclusions: These novel findings provide evidence that FAK is expressed by advanced-stage neuroblastoma and provide a rationale for targeting FAK in the treatment of this tumor.

Vascular endothelial growth factor receptor-3 promotes breast cancer cell proliferation, motility and survival in vitro and tumor formation in vivo.

Vascular endothelial growth factor receptor-3 is a receptor tyrosine kinase that is overexpressed in some human carcinomas, but its role in tumorigenesis has not been fully elucidated. We examined VEGFR-3 expression in normal, nonneoplastic and early stage malignant breast tissues and have shown that VEGFR-3 upregulation in breast cancer preceded tumor cell invasion, suggesting that VEGFR-3 may function as a survival signal. We characterized the biological effects of VEGFR-3 overexpression in human breast cancer cells based on two approaches: Gain of function by overexpressing VEGFR-3 in MCF-7 breast cancer cells and loss of function by RNAi-mediated silencing of VEGFR-3 in MCF-7-VEGFR-3 and BT474 cells.