Classification of patients with non-alcoholic fatty liver disease using rapid immunoassay of serum type IV collagen compared with liver histology and other fibrosis markers.

AIM: Non-alcoholic fatty liver disease (NAFLD) can progress to non-alcoholic fatty liver (NAFL) or non-alcoholic steatohepatitis (NASH). We investigated the association among serum type IV collagen level, liver histology, and other fibrosis markers in NAFLD progression. METHODS: We evaluated 184 patients diagnosed with NAFLD following biopsy, including 89 males and 95 females with an average age of 52.6 and 62.6 years, respectively. Non-alcoholic fatty liver disease was classified as NAFL or NASH using Matteoni's classification, and the grade and stage of NASH were assessed using Brunt's classification. Serum type IV collagen was measured by a rapid and sensitive latex particle-enhanced turbidimetric immunoassay. RESULTS: Forty-two patients with NAFL and 142 patients with NASH were included in this study. Compared with patients with NAFL, patients with NASH showed more significant liver function disorder and increased expression of fibrosis markers including type IV collagen, collagen 7S, Mac2-binding protein (M2BP), and hyaluronic acid (HA). Expression of type IV collagen and collagen 7S, but not M2BP and HA, was more significantly elevated in patients with stage 1 NASH than in patients with NAFL, indicating that type IV collagen and collagen 7S may be better discriminators of NASH and NAFL than M2BP and HA at an early stage of fibrosis. When patients were stratified by NAFLD activity score, type IV collagen and collagen 7S were significantly elevated as NAFLD activity score progressed, whereas M2BP and HA expression were not significantly elevated. CONCLUSION: Type IV collagen may be a useful measure of NASH severity as latex particle-enhanced turbidimetric immunoassay-based rapid type IV collagen assay can be carried out routinely.

Development of theoretical approach for describing electronic properties of hetero-interface systems under applied bias voltage.

We have developed a theoretical approach for describing the electronic properties of hetero-interface systems under an applied electrode bias. The finite-temperature density functional theory is employed for controlling the chemical potential in their interfacial region, and thereby the electronic charge of the system is obtained. The electric field generated by the electronic charging is described as a saw-tooth-like electrostatic potential. Because of the continuum approximation of dielectrics sandwiched between electrodes, we treat dielectrics with thicknesses in a wide range from a few nanometers to more than several meters. Furthermore, the approach is implemented in our original computational program named grid-based coupled electron and electromagnetic field dynamics (GCEED), facilitating its application to nanostructures. Thus, the approach is capable of comprehensively revealing electronic structure changes in hetero-interface systems with an applied bias that are practically useful for experimental studies. We calculate the electronic structure of a SiO2-graphene-boron nitride (BN) system in which an electrode bias is applied between the graphene layer and an electrode attached on the SiO2 film. The electronic energy barrier between graphene and BN is varied with an applied bias, and the energy variation depends on the thickness of the BN film. This is because the density of states of graphene is so low that the graphene layer cannot fully screen the electric field generated by the electrodes. We have demonstrated that the electronic properties of hetero-interface systems are well controlled by the combination of the electronic charging and the generated electric field.

Comparison of the pathological response of the mesorectal positive nodes between short-course chemoradiotherapy with delayed surgery and long-course chemoradiotherapy in patients with rectal cancer.

BACKGROUND: The aim of this study was to compare the pathological response of mesorectal positive nodes between short-course chemoradiotherapy with delayed surgery (SCRT-delay) and long-course chemoradiotherapy (LC-CRT) in patients with rectal cancer. METHOD: The resected primary tumor specimens following the two different approaches were assessed utilizing the tumor regression grade (TRG 0-4), and each positive lymph node was assessed according to the lymph node regression grade (LRG 1-3), with TRG 4 and LRG 3 indicating total regression. The lymph node sizes were measured to elucidate any correlation with LRG scores. RESULTS: Seventy-four patients with ypN-positive rectal cancer had 220 positive lymph nodes following the SCRT-delay, and 48 patients had 141 positive lymph nodes following the LC-CRT. The distribution of LRG 1/2/3 in the two groups was 123/72/25 and 60/31/50 (p < 0.001), respectively, and the distribution of TRG 0/1/2/3/4 in the two groups was 36/19/19/0 and 12/15/20/1 (p = 0.005), respectively. The requirements of total regression of positive lymph nodes were a primary tumor degenerated to TRG 3 with a size less than 6 mm in SCRT-delay (sensitivity, 60.9 %) or a primary tumor degenerated to TRG 2-4 with a size less than 5 mm at TRG 2 (sensitivity, 57.6 %) or 6 mm at TRG 3 and 4 (sensitivity, 84.2 %) in LC-CRT as indicated by the receiver operating characteristic curve analysis. CONCLUSION: The tumor regression effect of LC-CRT on the primary tumor and positive nodes was more favorable than SCRT-delay, and LC-CRT is able to predict the LRG 3 response with a high sensitivity.

Control of optical response of a supported cluster on different dielectric substrates.

We develop a computational method for optical response of a supported cluster on a dielectric substrate. The substrate is approximated by a dielectric continuum with a frequency-dependent dielectric function. The computational approach is based on our recently developed first-principles simulation method for photoinduced electron dynamics in real-time and real-space. The approach allows us to treat optical response of an adsorbate explicitly taking account of interactions at an interface between an adsorbate and a substrate. We calculate optical absorption spectra of supported Agn (n = 2, 54) clusters, changing the dielectric function of a substrate. By analyzing electron dynamics in real-time and real-space, we clarify the mechanisms for variations in absorption spectra, such as peak shifts and intensity changes, relating to various experimental results for optical absorption of supported clusters. Attractive and repulsive interactions between an adsorbate and a substrate result in red and blue shifts, respectively, and the intensity decreases by energy dissipation into a substrate. We demonstrate that optical properties can be controlled by varying the dielectric function of a substrate.

A'high tie'confers an increased risk of anastomotic leakage for lower rectal cancer surgery in patients treated with preoperative radiotherapy.

PURPOSE: This study aimed at analyzing retrospectively the risk factors for anastomotic leakage for lower rectal cancer treated with preoperative radiotherapy. METHODS: The subjects were 108 patients with T3 lower rectal cancer, who underwent curative resection following preoperative radiotherapy. All patients had a diverting stoma made. Univariate and multivariate analyses were conducted for the independent clinical variables. RESULTS: Anastomotic leakage developed in 19 (17.6 %) patients. Univariate analysis of the risk factors for anastomotic leakage revealed that arterial ligation with a high tie (p = 0.001), undifferentiated tumor type (p = 0.002), a shorter distance from the anal verge (p = 0.086), and a longer hospital stay (p = 0.0002) were significant predictors of leakage. Multivariate analysis revealed that a high tie [hazard ratio 12.22 (95 % confidence interval 2.83-87.94); p = 0.0003], undifferentiated tumor type [91.15 (5.98-3128.03); p = 0.0008], and a long hospital stay [13.03 (2.86-104.93); p = 0.0004] were independently associated with anastomotic leakage. CONCLUSION: Our data suggest that preoperative radiotherapy and a high tie for lower rectal cancer are independent risk factors for anastomotic leakage.

Laparoscopic intersphincteric resection and J-pouch reconstruction without laparotomy.

In some cases, a J-pouch is not created after laparoscopic intersphincteric resection (Lap-ISR), because this procedure usually does not involve laparotomy. This study aimed to develop a new technique for Lap-ISR and J-pouch reconstruction without laparotomy and to assess the short- and long-term outcomes of this technique. After a rectal specimen is excised using the transanal approach, the reconstructed intestine is reinserted into the intra-abdominal space. To create the J-shape, the reconstructed intestine is looped back using Allis forceps, and the septum of the J-shape is divided using a surgical stapler. We performed 20 surgeries using the new technique. Although three patients developed pelvic infections, no J-pouch-related complications were noted. Intestinal continuity could be maintained in all patients who received a diverting stoma.

The timing of surgery after preoperative short-course S-1 chemoradiotherapy with delayed surgery for T3 lower rectal cancer.

PURPOSE: The purpose of this study was to analyze the influence of variations in clinical practice regarding the timing of surgery with short-course chemoradiotherapy with delayed surgery (SCRT-delay) for lower rectal cancer. METHODS: A total of 171 patients with T3 N0-2 lower rectal cancer treated with SCRT-delay (25 Gy/10 fractions/5 days (S-1); days 1-10) were retrospectively evaluated. The median waiting period of 30 days was used as a discriminator (group A: waiting period, ≤30 days; group B: waiting period, ≥31 days). Preoperative treatment responses and oncological outcomes were analyzed. RESULTS: The mean waiting periods for groups A and B were 24.4 ± 5.3 and 41.4 ± 12.3 days, respectively. There were no statistically significant differences between the two groups in any of the clinical variables. The clinicopathological outcomes were as follows: T downstaging (43.5 vs 37.2 %; p = 0.400), negative yp N (67.1 vs 75.6 %; p = 0.218), pCR (7.1 vs 1.2 %; p = 0.119). The 5-year local recurrence-free survival (89.3 vs 87.6 %; p = 0.956), the recurrence-free survival (82.2 vs 78.8 %; p = 0.662), and the overall survival (88.5 vs 84.4 %; p = 0.741), all of which were similar between the two groups. CONCLUSIONS: The longer waiting period did not increase the tumor downstaging and not improve the oncological outcomes for T3 lower rectal cancer treated with SCRT-delay. In addition, considering that the impaired leukocyte response occurred during the sub-acute period, any time after the sub-acute period (day 12) up to 30 days after radiotherapy would be a suitable waiting period.

First-principles computational visualization of localized surface plasmon resonance in gold nanoclusters.

Cluster-size dependence of localized surface plasmon resonance (LSPR) for Aun nanoclusters (n = 54, 146, 308, 560, 922, 1414) is investigated by using our recently developed computational program of first-principles calculations for photoinduced electron dynamics in nanostructures. The size of Au1414 (3.9 nm in diameter) is unprecedentedly large in comparison with those addressed in previous first-principles calculations of optical response in nanoclusters. These computations enable us to clearly see that LSPR gradually grows and the LSPR peaks red shift with increasing cluster size. The growth of LSPR is visualized in real space, demonstrating that electron charge distributions oscillate in a collective manner around the outermost surface region of the clusters. We further illustrate that the core d electrons screen the collective oscillation of the conduction-like s electrons.

Theoretical approach for optical response in electrochemical systems: application to electrode potential dependence of surface-enhanced Raman scattering.

We propose a theoretical approach for optical response in electrochemical systems. The fundamental equation to be solved is based on a time-dependent density functional theory in real-time and real-space in combination with its finite temperature formula treating an electrode potential. Solvation effects are evaluated by a dielectric continuum theory. The approach allows us to treat optical response in electrochemical systems at the atomistic level of theory. We have applied the method to surface-enhanced Raman scattering (SERS) of 4-mercaptopyridine on an Ag electrode surface. It is shown that the SERS intensity has a peak as a function of the electrode potential. Furthermore, the real-space computational approach facilitates visualization of variation of the SERS intensity depending on an electrode potential.

Retrospective study of canine nasal tumor treated with hypofractionated radiotherapy.

The object of this study was to evaluate hypofractionated multiportal field and two-portion (rostral and caudal portions divided by the eyelid) radiation therapy for canine nasal tumors. Sixty-three dogs underwent multiportal hypofractionated radiation therapy. The radiation field was divided into rostral and caudal portions by the eyelid. Treatments were performed four times for 57 dogs. The median irradiation dose/fraction was 8 Gy (range, 5-10 Gy); the median total dose was 32 Gy (10-40 Gy). Improvement of clinical symptoms was achieved in 53 (84.1%) of 63 cases. Median survival time was 197 days (range, 2-1,080 days). Median survival times with and without destruction of the cribriform plate before radiotherapy were 163 and 219 days, respectively. There was no significant difference between them. No other factors were related to survival according to a univariate analysis. All radiation side effects, except one, were grade I according to the VRTOG classification. It was not necessary to treat any dogs for skin side effects. One dog (1.6%) developed an oronasal fistula 1 year after completion of radiation therapy. This radiation protocol may be useful in reducing radiation side effects in dogs with cribriform plate destruction.

[Metachronous urothelial cancer in bilateral upper urinary tracts and bladder associated with hereditary nonpolyposis colorectal cancer].

A 40-year-old man had undergone right hemicolectomy and sigmoidectomy under the diagnosis of ascending and sigmoid colon cancer and right nephroureterectomy under the diagnosis of right ureteral cancer, in 1997 and in 2002, respectively. In 2007, He visited our hospital with a complaint of bloody stool and hematuria. Colon fiberscopy, ureteropelvicscopy and cystoscopy demonstrated colon cancer, left renal pelvis cancer and bladder cancer, respectively, as diagnosed by biopsies, followed by restative colectomy, left nephroureterectomy and cystectomy. The final histopathological examination showed well differentiated adenocarcinoma (pSM) in the colon, and urothelial carcinoma in the left renal pelvis (pT2) and the bladder (pT1). Since his uncle and elder brother had suffered from stomach cancer and colon cancer, respectively, he was diagnosed with hereditary nonpolyposis colorectal cancer (HNPCC : Lynch syndrome). He has been well doing without recurrence for 3 years after the surgery.

Development of alternative gene transfer techniques for ex vivo and in vivo gene therapy in a canine model.

INTRODUCTION: Gene therapy have recently attracted much attention as a curative therapeutic option for inherited single gene disorders such as hemophilia. Hemophilia is a hereditary bleeding disorder caused by the deficiency of clotting activity of factor VIII (FVIII) or factor IX (FIX), and gene therapy for hemophilia using viral vector have been vigorously investigated worldwide. Toward further advancement of gene therapy for hemophilia, we have previously developed and validated the efficacy of novel two types of gene transfer technologies using a mouse model of hemophilia A. Here we investigated the efficacy and safety of the technologies in canine model. Especially, validations of technical procedures of the gene transfers for dogs were focused. METHODS: Green fluorescence protein (GFP) gene were transduced into normal beagle dogs by ex vivo and in vivo gene transfer techniques. For ex vivo gene transfer, blood outgrowth endothelial cells (BOECs) derived from peripheral blood of normal dogs were transduced with GFP gene using lentivirus vector, propagated, fabricated as cell sheets, then implanted onto the omentum of the same dogs. For in vivo gene transfer, normal dogs were subjected to GFP gene transduction with non-viral piggyBac vector by liver-targeted hydrodynamic injections. RESULTS: No major adverse events were observed during the gene transfers in both gene transfer systems. As for ex vivo gene transfer, histological findings from the omental biopsy performed 4 weeks after implantation revealed the tube formation by implanted GFP-positive BOECs in the sub-adipose tissue layer without any inflammatory findings, and the detected GFP signals were maintained over 6 months. Regarding in vivo gene transfer, analyses of liver biopsy samples revealed more than 90% of liver cells were positive for GFP signals in the injected liver lobes 1 week after gene transfers, then the signals gradually declined overtime. CONCLUSIONS: Two types of gene transfer techniques were successfully applied to a canine model, and the transduced gene expressions persisted for a long term. Toward clinical application for hemophilia patients, practical assessments of therapeutic efficacy of these techniques will need to be performed using a dog model of hemophilia and FVIII (or FIX) gene.

Functional regulation of von Willebrand factor ameliorates acute ischemia-reperfusion kidney injury in mice.

Acute kidney injury (AKI), an abrupt loss of renal function, is often seen in clinical settings and may become fatal. In addition to its hemostatic functions, von Willebrand factor (VWF) is known to play a role in cross-talk between inflammation and thrombosis. We hypothesized that VWF may be involved in the pathophysiology of AKI, major causes of which include insufficient renal circulation or inflammatory cell infiltration in the kidney. To test this hypothesis, we studied the role of VWF in AKI using a mouse model of acute ischemia-reperfusion (I/R) kidney injury. We analyzed renal function and blood flow in VWF-gene deleted (knock-out; KO) mice. The functional regulation of VWF by ADAMTS13 or a function-blocking anti-VWF antibody was also evaluated in this pathological condition. Greater renal blood flow and lower serum creatinine were observed after reperfusion in VWF-KO mice compared with wild-type (WT) mice. Histological analysis also revealed a significantly lower degree of tubular damage and neutrophil infiltration in kidney tissues of VWF-KO mice. Both human recombinant ADAMTS13 and a function-blocking anti-VWF antibody significantly improved renal blood flow, renal function and histological findings in WT mice. Our results indicate that VWF plays a role in the pathogenesis of AKI. Proper functional regulation of VWF may improve the microcirculation and vessel function in the kidney, suggesting a novel therapeutic option against AKI.

Second-look surgery following Hartmann's procedure for obstructive left-sided colorectal cancer.

The aim of the present study was to investigate the short- and long-term outcomes of patients undergoing second-look surgery following Hartmann's procedure for obstructive left-sided colorectal cancer (LSCC). All patients included in the present study had undergone radical surgery with Hartmann's procedure for obstructive LSCC. Adjuvant chemotherapy was recommended for all patients, and patients with no signs of recurrence following six months of surveillance were planned to undergo second-look surgery. The aim of second-look surgery was early detection of local recurrence and determination of the efficacy of laparoscopic Hartmann procedure reversal. A total of 15 patients with locally advanced colorectal cancer were included in the study. Three patients exhibited peritoneal dissemination at the time of laparoscopic Hartmann procedure reversal and underwent partial peritonectomy. Following adjuvant chemotherapy treatment, laparoscopic Hartmann procedure reversal was performed in all patients. However, two patients underwent colo-anal anastomosis, and two patients underwent right-sided colon or ileum reconstruction. Regarding the oncological outcomes, two of three patients in whom peritoneal dissemination was identified during laparoscopic Hartmann procedure reversal were eventually in remission following the initial surgery and the second-look surgery with partial peritonectomy. Favorable long-term outcomes were observed in 12/15 patients due to no recurrence, which may be due to the surgical techniques used and the timing of the second-look surgery following Hartmann's procedure for the treatment of obstructive LSCC.

Diffusion-weighted magnetic resonance imaging for prediction of tumor response to neoadjuvant chemoradiotherapy using irinotecan plus S-1 for rectal cancer.

The purpose of this study was to investigate the clinical value of diffusion-weighted (DW) magnetic resonance imaging (MRI) as a predictor of tumor response in patients receiving neoadjuvant chemoradiotherapy (NA-CRT) for rectal cancer (RC) through measurement of the apparent diffusion coefficient (ADC) value in each tumor. Neoadjuvant radiotherapy with a total dose of 45 Gy in 25 fractions was performed in all 16 patients with RC, combined with irinotecan and S-1. MRI was performed before and after NA-CRT. Multiple factors were assessed to predict the pathological response to NA-CRT. The pathological response rate was determined in 9 patients (56.3%). Statistical analyses indicated that the ADC value prior to NA-CRT was significantly lower in patients with a better response to NA-CRT (P=0.023). A cut-off value of 0.750×10-3 mm2/sec obtained by a receiver operating characteristic curve analysis indicated a sensitivity of 77.8% and specificity of 85.7% for pathological responders to NA-CRT. In addition, the patients with lower ADC values exhibited a greater pathological response to NA-CRT (P=0.041). In conclusion, the ADC value of MRI of RC patients treated with NA-CRT followed by surgery may provide valuable information to predict the response to NA-CRT.

Pathologic evaluation of the response of mesorectal positive nodes to preoperative chemoradiotherapy in patients with rectal cancer.

BACKGROUND: The response of positive mesorectal lymph nodes to chemoradiotherapy remains largely unstudied in patients with rectal cancer. The aim of this study was to investigate the requirements of the total regression of positive nodes treated with chemoradiotherapy. METHODS: The response of the primary tumor was evaluated according to the tumor regression grade (TRG 0-4) in resected specimens, and positive lymph nodes were assessed according to the lymph node regression grade (LRG 1-3), with TRG 4 and LRG 3 indicating total regression. We investigated the relationships among TRG, LRG, and the sizes of positive lymph nodes. RESULTS: Among 178 patients, 68 (38.2%) had 200 positive lymph nodes. We first investigated the relationship of positive nodes to TRG and LRG and found that the response of the primary tumor to chemoradiotherapy correlated with the response of positive nodes. Next, we investigated the correlation between LRG and the size of positive nodes. At TRG 1 and 2, LRG score was not correlated with the positive node size. In contrast, at TRG 3, LRG score was correlated with the size of positive nodes. Next, our assessment of the relationship between the sizes of positive nodes and complete degeneration to LRG 3 showed that the most accurate cut-off score on receiver-operator-characteristics curve analysis was 6 mm in maximum diameter for TRG 3. CONCLUSION: The requirements of the total regression of positive nodes are 1) degeneration of the primary tumor to TRG 3 and 2) a positive node diameter of <6 mm.

Short-course radiotherapy with delayed surgery versus conventional chemoradiotherapy: A comparison of the short- and long-term outcomes in patients with T3 rectal cancer.

INTRODUCTION: The aim of this study was to compare the short- and long-term outcomes between short-course radiotherapy with delayed surgery (SRT-delay) and a standard conventional chemoradiotherapy (CRT) regimen. METHODS: Two collaborating institutions adopted different regimens; the SRT-delay regimen was selected by Meiwa Hospital and the CRT regimen was selected by Hyogo College of Medicine. The inclusion criteria were T3 middle and low rectal cancer patients treated with radical surgery after preoperative therapy. The median follow-up period was 44 months (range, 12-85). RESULTS: From 2007 to 2013, 104 patients were treated using the SRT-delay regimen and 61 patients were treated using the CRT regimen. The pretreatment characteristics of the 2 groups were not significantly different. The sphincter-preserving rate (93.3%, 85.2%), T downstaging (37.5%, 37.7%), ypN(-) (74.0%, 67.2%), postoperative complications and the bowel, and urinary and sexual functioning of the SRT-delay regimen were noninferior to those of the CRT regimen. The 3-year local recurrence-free survival, recurrence-free survival, and overall survival in the SRT-delay and CRT groups were 90.6% and 90.6% (P = .764), 83.8% and 78.3% (P = .687) and 96.0% and 92.8% (P = .833), respectively. CONCLUSION: The SRT-delay regimen was noninferior in terms of the downstaging effect, and oncologic and functional outcomes compared with the CRT regimen for T3 middle and low rectal cancer.

Ring Expansion of Diazo-Functionalized 4-Hydroxycyclobutenone: Catalytic Ring Opening and Recyclization to 2(5H)-Furanone/Cyclopentenedione and Thermal 4pi-8pi Electrocyclic Ring Opening-Closure to Diazepinedione.

The acid-catalyzed and Rh-catalyzed (also photolyzed) decomposition of 4-hydroxycyclobutenones with a diazo group at C-4 gave 2(5H)-furanone and/or cyclopentene-1,3-dione via an alpha-carbocation intermediate and a carbenoid (carbene) intermediate, respectively. Thermal rearrangement of some of these compounds led to the formation of diazepinediones without the extrusion of nitrogen through tandem 4pi electrocyclic ring opening and 8pi electrocyclic ring closure processes.

Influence of position of substituent groups on removal of chlorophenols and cresols by horseradish peroxidase and determination of optimum conditions.

Enzymatic treatment of o-, m-, and p-chlorophenols and o-, m-, and p-cresols from artificial wastewater was undertaken through the enzymatic conversion into the corresponding phenoxy radicals with horseradish peroxidase (HRP) and nonenzymatic radical coupling reaction. The concentration of chlorophenols and cresols decreased sharply over the reaction time and water-insoluble oligomer precipitates were generated. The optimum conditions were determined to be the H2O2 concentration of 2.5 mM and poly(ethylene glycol) with molecular mass of 1.0 x 10(4) (10K-PEG) of 0.10 mg/cm3 at 30 degrees C for treatment of p-chlorophenol at 2.5 mM. The optimum pH values depended on the relative position of a chlorine atom for chlorophenols and on a methyl group for cresols. Concentrations of HRP and 10K-PEG were increased to 1.0 U/cm3 and 1.0 mg/cm3 respectively to treat m-chlorophenol highly. For o-chlorophenol, a decrease in the pH value to 3.0 after the enzymatic treatment led to the enhancement of the aggregation of oligomer precipitates. The % residual value for o-cresol effectively decreased by absorbing water-soluble intermediates on the chitosan films. These results indicate that chlorophenols and cresols were removed to a great degree by this technique, although the detailed procedure depended on the position of substituent groups of chlorophenols and cresols.

c-myc amplification and enhancement of sensitivity to cytosine arabinoside: an in vitro and in vivo study on four sublines established from a pulmonary adenocarcinoma.

PURPOSE: Meticulous treatment strategies taking tumor heterogeneity into account are considered essential to achieve breakthroughs in current cancer therapy. We analyzed tumor heterogeneity in the primary tumor of a patient with pulmonary adenocarcinoma characterized by a poor prognosis. METHODS: Four sublines with different growth characteristics in vitro were established from the tumor using a method for short-term selective cultivation. We examined the differences in morphological, biochemical, and genetic findings of these sublines. RESULTS: Differences in the histological features of the transplanted tumors were seen in the four sublines. The 88-2T and 88-2 tumors revealed a well-differentiated adenocarcinoma; the 88-2F tumor revealed a large cell-like carcinoma resembling the metastatic tumor in the lymph nodes; and the 88-2FA tumor was composed of signet-ring cells. There were differences in oncogenes, with the 88-2F line alone exhibiting 12-fold amplification of c-myc. Sensitivity to cytosine arabinoside (Ara C) was specifically increased in the 88-2F cell line, alone. CONCLUSIONS: These sublines demonstrate that human pulmonary adenocarcinoma has various types of heterogeneity within the primary tumor. Furthermore, c-myc amplification may play an important role in altering phenotype and growth characteristics in vitro and in vivo, and for increasing sensitivity to Ara C and the potential of cancer cells to metastasize to lymph nodes.