Charles LeVea

Significance of Signet-Ring Cells in Patients with Colorectal Cancer

PurposeWe performed a retrospective study to determine the pattern of metastases and overall outcome of patients with tumors exhibiting a component of signet-ring cells comprising < 50 percent of the tumor mass.MethodsMedical records of 753 patients with primary colorectal cancer were retrospectively studied. Patients who had tumors with < 50 percent signet-ring cells were classified as having a component of signet-ring cells. The outcome of patients with a component of signet-ring cells was compared to all patients with mucinous adenocarcinoma (defined as adenocarcinomas with ≥ 50 percent mucin) to all patients with adenocarcinomas with a component of mucin (defined as adenocarcinomas with < 50 percent mucin) and to 100 randomly selected patients with adenocarcinomas lacking mucin or signet-ring cells.ResultsFive percent of patients had a component of signet-ring cells, 3 percent had mucinous adenocarcinoma, 9 percent had a component of mucinous adenocarcinoma, and 83 percent had adenocarcinoma lacking mucinous or signet components. Patients with a component of signet-ring cells and mucinous adenocarcinomas metastasized predominantly to the peritoneum/ovaries (75 and 56 percent of metastatic cases, respectively) and rarely to liver/lungs. The pattern of metastases of patients with adenocarcinoma without mucinous or signet components predominantly involved the liver/lungs and rarely the peritoneum/ovaries (12.5 percent). The pattern of metastases for patients with a component of mucinous adenocarcinoma was intermediate between mucinous adenocarcinoma and adenocarcinoma without mucin or signet-ring component. No differences in survival in Stage IV patients were seen among the four subgroups.ConclusionsPatients with a component of signet-ring cells cancers, similar to mucinous adenocarcinoma, have a predisposition to metastasize to the peritoneum/ovaries.

Mutant PIK3CA-Bearing Colon Cancer Cells Display Increased Metastasis in an Orthotopic Model

Mutations in the PIK3CA gene are common in human cancers, including colon cancer. We compared two pairs of colon cancer cells (HCT116 and DLD1) bearing only the wild-type (WT) or mutant (MUT) PIK3CA allele for their survival capacity under stress conditions in vitro as well as their metastatic properties in an in vivo orthotopic model. When subjected to growth factor deprivation stress (GFDS), the MUT PIK3CA cells displayed resistance to GFDS-induced apoptosis relative to the WT cells. Phosphatidylinositol 3-kinase (PI3K) and its downstream effector AKT were constitutively activated during stress conditions in the MUT PIK3CA cells but not in the WT cells. The MUT cells showed hypersensitivity to PI3K inhibition. Moreover, the proapoptotic protein Bax was expressed at a very high level in the WT PIK3CA cells, whereas it was almost undetectable in the MUT cells. Inhibition of Bax expression by small interfering RNA protected the WT PIK3CA cells from GFDS-induced apoptosis, suggesting an important role of Bax in GFDS-induced apoptosis. These results indicated that the MUT PI3K confers resistance to GFDS-induced apoptosis and that the MUT cells are more dependent on the PI3K pathway for survival. In vivo studies showed that the MUT PIK3CA-bearing cells were more metastatic than the WT cells in an orthotopic model of colon cancer. Taken together, these results suggest that MUT PI3K imparts a more aggressive phenotype in colon cancer cells and could be a potential therapeutic target for treatment of colon cancer patients bearing PIK3CA mutations.

Phase II Study of Weekly Intravenous Oxaliplatin Combined With Oral Daily Capecitabine and Radiotherapy With Biologic Correlates in Neoadjuvant Treatment of Rectal Adenocarcinoma

PURPOSE To evaluate the efficacy of a combination of capecitabine, oxaliplatin, and radiotherapy (RT) in the neoadjuvant treatment of Stage II and III rectal cancers. METHODS Capecitabine was given at 725 mg/m(2) orally twice daily Monday through Friday concurrently with RT. Oxaliplatin was given intravenously at 50 mg/m(2) once weekly five times starting the first day of RT. The radiation dose was 50.4 Gy in 28 fractions (1.8 Gy/fraction), five fractions weekly. Endorectal tumor biopsies were obtained before treatment and on the third day of treatment to explore the effects of treatment on thymidine phosphorylase, thymidylate synthase, excision repair cross-complementing rodent repair deficiency complementation group 1 (ERCC1), and apoptosis. RESULTS A total of 25 patients were enrolled in this study; 6 patients (24%) had a complete pathologic response. T-downstaging occurred in 52% of patients, and N-downstaging occurred in 53%. Grade 3 diarrhea was the most common Grade 3-4 toxicity, occurring in 20% of patients. Only 2 patients experienced disease recurrence, with a median of 20 months of follow-up. Thymidylate synthase, thymidine phosphorylase, ERCC1, and apoptosis did not vary significantly between the pretreatment and Day 3 tumor biopsies, nor did they predict for T-downstaging or a complete pathologic response. CONCLUSION Capecitabine at 725 mg/m(2) orally twice daily, oxaliplatin 50 mg/m(2)/wk, and RT at 50.4 Gy is an effective neoadjuvant combination for Stage II and III rectal cancer and results in a greater rate of complete pathologic responses than historically shown in fluoropyrimidine plus RT controls.

Pilot study of gefitinib, oxaliplatin, and radiotherapy for esophageal adenocarcinoma: tissue effect predicts clinical response.

Purpose:Overexpression of epidermal growth factor receptor (EGFR) in esophageal cancer is associated with poor prognosis. Preclinical studies indicate synergism between the EGFR inhibitor gefitinib and oxaliplatin or radiotherapy (RT). We report here early results of a planned phase I/II study of gefitinib, oxaliplatin, and RT for locally advanced, unresectable esophageal cancer. Methods and Materials:The protocol consisted of oral gefitinib 250 mg daily for 1 year plus intravenous oxaliplatin 85 or 100 mg/m2 on days 1, 15, and 29, and RT (50.4 Gy in 28 1.8-Gy fractions). Four-quadrant biopsies were obtained at 1-cm intervals along the length of the tumor before and after treatment and the specimens were immunostained for EGFR, Erk, Akt, and their phosphorylated (activated) forms. Results:Enrollment was halted at 6 evaluable cases [all male; median age, 72.5 years (range, 51–75); and all with Eastern Cooperative Oncology Group performance status of 1]. All 6 tumors were adenocarcinomas; 5 were stage III and 1 stage IVA. Oxaliplatin was given at 85 mg/m2 in 3 cases and at 100 mg/m2 in 3 cases. Gefitinib therapy lasted a median 24 weeks; the median number of oxaliplatin doses was 6.5. Best responses were mucosal complete response (n = 1), partial response (n = 1), stable disease (n = 1), and progressive disease (n = 3). EGFR was expressed by tumor in 5 cases and Erk and Akt in 6 cases before treatment; no changes were noted after treatment. EGFR expression did not correlate with survival or response. No grade 4 toxicities were noted; grade 3 toxicities were diarrhea (n = 1), vomiting (n = 1), fatigue (n = 1), and constipation (n = 2). Median overall and disease-free survival times were 10.8 months and 8.4 months. Conclusions:Gefitinib in combination with oxaliplatin and RT was tolerable, but had limited clinical activity and did not down-regulate total or activated EGFR, Akt, or Erk in esophageal tumor samples.

Epidermal Growth Factor Receptor-Directed Therapy in Esophageal Cancer

Esophageal adenocarcinoma (EAC) is one of the fastest growing malignancies in the US. The long-term survival of patients with this cancer remains poor; only 25% of patients undergoing surgical excision are alive after 5 years. Multimodal programs that incorporate radiotherapy, chemotherapy and surgery for localized tumors may result in a modest survival advantage. However, significant strides in this disease can result from the inclusion of targeted therapies. The epidermal growth factor receptor (EGFR) family represents one such target and is receiving increasing attention due to the advent of specific inhibitors. Studies conducted by us and others have shown that the overexpression of EGFR family signaling intermediates is common in Barrett’s esophagus and EAC. In the latter case, EGFR expression may have prognostic significance. EGFR inhibitors, including oral tyrosine kinase inhibitors and monoclonal antibodies, result in a synergistic antitumor effect with chemotherapeutic agents or with radiotherapy. Therefore, several ongoing studies include EGFR-directed therapy either alone or in combination with chemoradiotherapy for this disease. Our study of gefitinib, oxaliplatin and radiotherapy suggested that gefitinib can be safely incorporated into an oxaliplatin-based chemoradiation program for esophageal cancer, although the clinical activity of this combination is modest. Herein, we review the current literature on this subject.

Eculizumab therapy for gemcitabine induced hemolytic uremic syndrome: case series and concise review

The incidence of gemcitabine-induced hemolytic uremic syndrome (GiHUS) has been reported to be between 0.02% and 2.2% (1,2). A variety of therapies have been employed in the treatment of GiHUS with varying success. In some cases the discontinuation of drug will result in remission of HUS (3). The benefit of plasmapheresis in the treatment of atypical forms of HUS (aHUS) such as GiHUS has been questioned (4). Other treatment modalities have been used with varying rates of success including high dose corticosteroids, vincristine, and rituximab (3,5). Eculizumab is a monoclonal antibody directed against the complement protein C5 that has been recently approved for treatment of atypical HUS (3). We report four cases of GiHUS seen over 2-month period and successfully treated with eculizumab.

Oral interleukin-10 alleviates polyposis via neutralization of pathogenic T-regulatory cells

Immune dysregulation drives the pathogenesis of chronic inflammatory, autoimmune, and dysplastic disorders. While often intended to address localized pathology, most immune modulatory therapies are administered systemically and carry inherent risk of multiorgan toxicities. Here, we demonstrate, in a murine model of spontaneous gastrointestinal polyposis, that site-specific uptake of orally administered IL10 microparticles ameliorates local and systemic disease to enhance survival. Mechanistic investigations showed that the therapeutic benefit of this treatment derived from neutralization of disease-promoting FoxP3(+)RoRγt(+)IL17(+) pathogenic T-regulatory cells (pgTreg), with a concomitant restoration of FoxP3(+)RoRγt(-)IL17(-) conventional T-regulatory cells (Treg). These findings provide a proof-of-principle for the ability of an oral biologic to restore immune homeostasis at the intestinal surface. Furthermore, they implicate local manipulation of IL10 as a tractable therapeutic strategy to address the inflammatory sequelae associated with mucosal premalignancy.

The Effects of Epidermal Growth Factor Receptor Activation and Attenuation of the TGFβ Pathway in an Orthotopic Model of Colon Cancer

BACKGROUND Colorectal cancer is the second leading cause of cancer related mortality, with a majority of deaths resulting from metastases. Few in vivo models allow for the study of the complex process of metastasis. The purpose of this study was to determine the effects of epidermal growth factor receptor activation and TGFbeta pathway attenuation in FET, a weakly tumorigenic human colon cancer cell line, in an orthotopic model. METHODS AND RESULTS Using FET, FETalpha, FETalphaDNRII, and FETDNRII cells were constructed. Tumors were orthotopically implanted onto the colons of BALB/c nude mice. After 7 wk, the mice were euthanized and organs extracted for examination. All cell lines demonstrated primary invasion. FETalpha was weakly metastatic compared with FETalphaDNRII and FETDNRII, which demonstrated metastases to the lung and liver, respectively. CONCLUSION Epidermal growth factor receptor (EGFR) activation transforms a nontumorigenic cell line into a tumorigenic but not metastatic one. The tumorigenic line becomes metastatic with the attenuation of TGFbeta signaling. Loss of EGFR activation in the TGFbeta inhibited line results in a decreased metastatic burden, but importantly, changes the organotropic homing from lung to liver. Thus, these in vivo studies demonstrate that EGFR activation and TGFbeta signaling pathways play a role in tumorigenicity and in pattern of metastases.

Expression of intestinal trefoil factor (TFF-3) in hepatocellular carcinoma

AbstractBackground: Trefoil peptides (TFF-1, 2, 3) are a family of protease-resistant regulatory factors that play a role in mucosal restitution, angiogenesis, apoptosis, and tumor progression. Intestinal trefoil peptide (TFF-3) expression has been demonstrated in benign hepatobiliary diseases, but there are limited data regarding its expression in HCC. Methods: Thirty consecutive cases of HCC from 1998 to 2003 were studied. Immunohistochemistry was performed on formalin-fixed paraffin-embedded blocks of HCC using polyclonal antibody to TFF-3. TFF-3 expression was classified as strong, moderate, weak, focal, and negative. Clinical data were obtained per an IRB-approved protocol. Results: Median age was 69 yr (range: 39–83 yr). Twenty- three patients were males and 7 were females. Treatments included hepatic resection (n=16), chemo-embolization (n=4), combined modality therapy (n=5) and no treatment (n=4). HCC was well differentiated in 12 (40%), moderately differentiated in 13 (43%), and poorly differentiated in 5 (17%) patients. TFF-3 expression was detected in 28/30 (93.3%) patient samples. Sixteen patients (53%) had moderate and 1 (3%) patient had strong TFF-3 expression. Tumor/normal tissue interface was assessable in 21 cases; 11 cases expressed TFF-3 at the interface. There was a strong correlation between tumor grade and TFF-3 expression, wherein poorly differentiated tumors had moderate/strong TFF-3 expression (p=0.008). There was no correlation between TFF-3 expression and survival (p=0.77). Furthermore, there was no correlation among age, disease stage, and survival. Conclusion: TFF-3 is commonly expressed in HCC and its expression correlates with tumor grade.

Erlotinib and Radiation Therapy for Elderly Patients with Esophageal Cancer - Clinical and Correlative Results from a Prospective Multicenter Phase 2 Trial

Purpose: Elderly patients with esophageal cancer who are not candidates for chemoradiation may benefit from targeted agents; hence erlotinib combined with radiotherapy was evaluated in this trial. Materials and Methods: Patients >65 years with carcinoma of the thoracic esophagus or gastroesophageal junction who were not eligible for platinum-based treatment received erlotinib daily for 1 year starting on day 1 of radiotherapy [50.4 Gy days 1-28 (Mon-Fri) at 1.8 Gy per fraction]. Response was assessed by endoscopy and computed tomography. The primary endpoint was overall survival (OS), and secondary endpoints were complete response, progression-free survival (PFS) and toxicity. Results: The ECOG performance status in the 17 study patients was 0,1 and 2 in 2, 12 and 3 patients, respectively; 1, 5, 7 and 4 patients were in stage I, II, III and IV, respectively; adenocarcinoma was noted in 16 patients and squamous cell carcinoma in 1; there were 3 current, 12 past and 2 never smokers. Median OS was 7.3 months (95% confidence interval, CI: 3.8-22.3) with 14 deaths. There were 2 mucosal complete responses, 1 residual carcinoma in situ and 3 partial endoscopic responses in 9 patients who had endoscopy after radiotherapy. Estimated PFS was 4.5 months (95% CI: 2.4-7.3). Progression was distant (n = 3), locoregional (n = 6), unknown (n = 5) and too early (n = 3). Estimated 1-year survival was 29% (95% CI: 11-51%), 5 patients lived >12 months. Treatment-related toxicities of grade 3-4 occurred in 5 patients. Patients with epidermal growth factor receptor amplification and never smokers had the longest OS (22.3 and 16.6 months, respectively). Conclusions: Erlotinib with radiotherapy is tolerable and warrants further biomarker-driven evaluation in this population.